diff --git "a/wikipedia_20.txt" "b/wikipedia_20.txt" new file mode 100644--- /dev/null +++ "b/wikipedia_20.txt" @@ -0,0 +1,10000 @@ + 1900 – Tebbs Lloyd Johnson, English race walker (d. 1984) + +1901–present +1902 – Eduard Eelma, Estonian footballer (d. 1941) +1903 – M. Balasundaram, Sri Lankan lawyer and politician (d. 1965) + 1903 – Edwin T. Layton, American admiral (d. 1984) +1904 – Roland Wilson, Australian economist and statistician (d. 1996) +1908 – Percy Faith, Canadian composer, conductor, and bandleader (d. 1976) + 1908 – Pete Zaremba, American hammer thrower (d. 1994) +1909 – Robert Charroux, French author and critic (d. 1978) +1910 – Melissanthi, Greek poet, teacher and journalist (d. 1990) +1913 – Louise Currie, American actress (d. 2013) + 1913 – Charles Vanik, American soldier, judge, and politician (d. 2007) +1914 – Ralph Flanagan, American pianist, composer, and conductor (d. 1995) + 1914 – Domnitsa Lanitou-Kavounidou, Greek sprinter (d. 2011) +1915 – Stanley Adams, American actor and screenwriter (d. 1977) + 1915 – Billie Holiday, American singer-songwriter and actress (d. 1959) + 1915 – Henry Kuttner, American author (d. 1958) +1916 – Anthony Caruso, American actor (d. 2003) +1917 – R. G. Armstrong, American actor and playwright (d. 2012) +1918 – Bobby Doerr, American baseball player and coach (d. 2017) +1919 – Roger Lemelin, Canadian author and screenwriter (d. 1992) + 1919 – Edoardo Mangiarotti, Italian fencer (d. 2012) +1920 – Ravi Shankar, Indian-American sitar player and composer (d. 2012) +1921 – Feza Gürsey, Turkish mathematician and physicist (d. 1992) +1922 – Mongo Santamaría, Cuban-American drummer (d. 2003) +1924 – Johannes Mario Simmel, Austrian-English author and screenwriter (d. 2009) +1925 – Chaturanan Mishra, Indian trade union leader and politician (d. 2011) + 1925 – Jan van Roessel, Dutch footballer (d. 2011) +1927 – Babatunde Olatunji, Nigerian-American drummer, educator, and activist (d. 2003) + 1927 – Leonid Shcherbakov, Russian triple jumper +1928 – James Garner, American actor, singer, and producer (d. 2014) + 1928 – Alan J. Pakula, American director, producer, and screenwriter (d. 1998) + 1928 – James White, Northern Irish author and educator (d. 1999) +1929 – Bob Denard, French soldier (d. 2007) + 1929 – Joe Gallo, American gangster (d. 1972) +1930 – Jane Priestman, English interior designer (d. 2021) + 1930 – Yves Rocher, French businessman, founded the Yves Rocher Company (d. 2009) + 1930 – Andrew Sachs, German-English actor and screenwriter (d. 2016) + 1930 – Roger Vergé, French chef and restaurateur (d. 2015) +1931 – Donald Barthelme, American short story writer and novelist (d. 1989) + 1931 – Daniel Ellsberg, American activist and author (d. 2023) +1932 – Cal Smith, American singer and guitarist (d. 2013) +1933 – Wayne Rogers, American actor, investor, and producer (d. 2015) + 1933 – Sakıp Sabancı, Turkish businessman and philanthropist (d. 2004) +1934 – Ian Richardson, Scottish-English actor (d. 2007) +1935 – Bobby Bare, American singer-songwriter and guitarist + 1935 – Hodding Carter III, American journalist and politician, Assistant Secretary of State for Public Affairs +1937 – Charlie Thomas, American singer (d. 2023) +1938 – Jerry Brown, American lawyer and politician, 34th and 39th Governor of California + 1938 – Spencer Dryden, American drummer (d. 2005) + 1938 – Freddie Hubbard, American trumpet player and composer (d. 2008) + 1938 – Iris Johansen, American author +1939 – Francis Ford Coppola, American director, producer, and screenwriter + 1939 – David Frost, English journalist and game show host (d. 2013) + 1939 – Gary Kellgren, American record producer, co-founded Record Plant (d. 1977) + 1939 – Brett Whiteley, Australian painter (d. 1992) +1940 – Marju Lauristin, Estonian academic and politician, 1st Estonian Minister of Social Affairs +1941 – James Di Pasquale, American composer + 1941 – Peter Fluck, English puppet maker and illustrator + 1941 – Cornelia Frances, English-Australian actress (d. 2018) + 1941 – Gorden Kaye, English actor (d. 2017) +1942 – Jeetendra, Indian actor, TV and film producer +1943 – Mick Abrahams, English singer-songwriter and guitarist + 1943 – Dennis Amiss, English cricketer and manager +1944 – Shel Bachrach, American insurance broker, investor, businessman and philanthropist + 1944 – Warner Fusselle, American sportscaster (d. 2012) + 1944 – Oshik Levi, Israeli singer and actor + 1944 – Julia Phillips, American film producer and author (d. 2002) + 1944 – Gerhard Schröder, German lawyer and politician, 7th Chancellor of Germany + 1944 – Bill Stoneman, American baseball player and manager +1945 – Megas, Icelandic singer-songwriter + 1945 – Gerry Cottle, English circus owner (d. 2021) + 1945 – Marilyn Friedman, American philosopher and academic + 1945 – Martyn Lewis, Welsh journalist and author + 1945 – Joël Robuchon, French chef and author (d. 2018) + 1945 – Werner Schroeter, German director and screenwriter (d. 2010) + 1945 – Hans van Hemert, Dutch songwriter and producer +1946 – Zaid Abdul-Aziz, American basketball player + 1946 – Colette Besson, French runner and educator (d. 2005) + 1946 – Herménégilde Chiasson, Canadian poet, playwright, and politician, 29th Lieutenant Governor of New Brunswick + 1946 – Dimitrij Rupel, Slovenian politician and diplomate + 1946 – Stan Winston, American special effects designer and makeup artist (d. 2008) +1947 – Patricia Bennett, American singer + 1947 – Florian Schneider, German singer and drummer (d. 2020) + 1947 – Michèle Torr, French singer and author +1948 – John Oates, American singer-songwriter guitarist, and producer + 1948 – Arnie Robinson, American athlete (d. 2020) + 1948 – Ecaterina Andronescu, Romanian politician +1949 – Mitch Daniels, American academic and politician, 49th Governor of Indiana +1950 – Brian J. Doyle, American press secretary + 1950 – Neil Folberg, American-Israeli photographer +1951 – Bruce Gary, American drummer (d. 2006) + 1951 – Janis Ian, American singer-songwriter and guitarist +1952 – David Baulcombe, English geneticist and academic + 1952 – Jane Frederick, American hurdler and heptathlete + 1952 – Gilles Valiquette, Canadian actor, singer, and producer + 1952 – Dennis Hayden, American actor +1953 – Santa Barraza, American mixed media artist + 1953 – Douglas Kell, English biochemist and academic +1954 – Jackie Chan, Hong Kong martial artist, actor, stuntman, director, producer, and screenwriter + 1954 – Tony Dorsett, American football player +1955 – Tim Cochran, American mathematician and academic (d. 2014) + 1955 – Gregg Jarrett, American lawyer and journalist +1956 – Annika Billström, Swedish businesswoman and politician, 16th Mayor of Stockholm + 1956 – Christopher Darden, American lawyer and author + 1956 – Georg Werthner, Austrian decathlete +1957 – Kim Kap-soo, South Korean actor + 1957 – Thelma Walker, British politician +1958 – Brian Haner, American singer-songwriter and guitarist + 1958 – Hindrek Kesler, Estonian architect +1960 – Buster Douglas, American boxer and actor + 1960 – Sandy Powell, English costume designer +1961 – Thurl Bailey, American basketball player and actor + 1961 – Pascal Olmeta, French footballer + 1961 – Brigitte van der Burg, Tanzanian-Dutch geographer and politician +1962 – Jon Cruddas, English lawyer and politician + 1962 – Andrew Hampsten, American cyclist +1963 – Jaime de Marichalar, Spanish businessman + 1963 – Nick Herbert, English businessman and politician, Minister for Policing + 1963 – Dave Johnson, American decathlete and educator +1964 – Jace Alexander, American actor and director + 1964 – Russell Crowe, New Zealand-Australian actor + 1964 – Steve Graves, Canadian ice hockey player +1965 – Bill Bellamy, American comedian, actor, and producer + 1965 – Rozalie Hirs, Dutch composer and poet + 1965 – Alison Lapper, English painter and photographer + 1965 – Nenad Vučinić, Serbian-New Zealand basketball player and coach +1966 – Richard Gomez, Filipino actor and politician + 1966 – Zvika Hadar, Israeli entertainer + 1966 – Béla Mavrák, Hungarian tenor singer + 1966 – Gary Wilkinson, English snooker player +1967 – Artemis Gounaki, Greek-German singer-songwriter + 1967 – Bodo Illgner, German footballer + 1967 – Simone Schilder, Dutch tennis player +1968 – Duncan Armstrong, Australian swimmer and sportscaster + 1968 – Jennifer Lynch, American actress, director, producer, and screenwriter + 1968 – Jože Možina, Slovenian historian, sociologist and journalist + 1968 – Vasiliy Sokov, Russian triple jumper +1969 – Ricky Watters, American football player +1970 – Leif Ove Andsnes, Norwegian pianist and educator + 1970 – Alexander Karpovtsev, Russian ice hockey player and coach (d. 2011) +1971 – Guillaume Depardieu, French actor (d. 2008) + 1971 – Victor Kraatz, German-Canadian figure skater +1972 – Tim Peake, British astronaut +1973 – Marco Delvecchio, Italian footballer + 1973 – Jeanine Hennis-Plasschaert, Dutch lawyer and politician, Dutch Minister of Defence + 1973 – Carole Montillet, French skier + 1973 – Christian O'Connell, British radio DJ and presenter + 1973 – Brett Tomko, American baseball player +1975 – Karin Dreijer Andersson, Swedish singer-songwriter and producer + 1975 – Ronde Barber, American football player and sportscaster + 1975 – Tiki Barber, American football player and journalist + 1975 – Ronnie Belliard, American baseball player + 1975 – John Cooper, American singer-songwriter and bass player + 1975 – Simon Woolford, Australian rugby league player +1976 – Kevin Alejandro, American actor and producer + 1976 – Martin Buß, German high jumper + 1976 – Jessica Lee, English lawyer and politician + 1976 – Aaron Lohr, American actor + 1976 �� Barbara Jane Reams, American actress + 1976 – Gang Qiang, Chinese anchor +1977 – Tama Canning, Australian-New Zealand cricketer + 1977 – Karin Haydu, Slovak actress +1978 – Jo Appleby, English soprano + 1978 – Duncan James, English singer-songwriter and actor + 1978 – Lilia Osterloh, American tennis player +1979 – Adrián Beltré, Dominican-American baseball player + 1979 – Patrick Crayton, American football player + 1979 – Pascal Dupuis, Canadian ice hockey player + 1979 – Danny Sandoval, Venezuelan-American baseball player +1980 – Dragan Bogavac, Montenegrin footballer + 1980 – Bruno Covas, Brazilian lawyer, politician (d. 2021) + 1980 – Tetsuji Tamayama, Japanese actor +1981 – Hitoe Arakaki, Japanese singer +1981 – Kazuki Watanabe, Japanese songwriter and guitarist (d. 2000) + 1981 – Vanessa Olivarez, American singer-songwriter, and actress + 1981 – Suzann Pettersen, Norwegian golfer +1982 – Silvana Arias, Peruvian actress + 1982 – Sonjay Dutt, American wrestler + 1982 – Kelli Young, English singer +1983 – Hamish Davidson, Australian musician + 1983 – Franck Ribéry, French footballer + 1983 – Jon Stead, English footballer + 1983 – Jakub Smrž, Czech motorcycle rider + 1983 – Janar Talts, Estonian basketball player +1984 – Hiroko Shimabukuro, Japanese singer +1985 – KC Concepcion, Filipino actress and singer + 1985 – Humza Yousaf, Scottish politician +1986 – Brooke Brodack, American comedian + 1986 – Jack Duarte, Mexican actor, singer, and guitarist + 1986 – Andi Fraggs, English singer-songwriter and producer + 1986 – Christian Fuchs, Austrian footballer +1987 – Martín Cáceres, Uruguayan footballer + 1987 – Eelco Sintnicolaas, Dutch decathlete + 1987 – Jamar Smith, American football player +1988 – Antonio Piccolo, Italian footballer + 1988 – Ed Speleers, English actor and producer +1989 – Franco Di Santo, Argentinian footballer + 1989 – Mitchell Pearce, Australian rugby league player + 1989 – Teddy Riner, French judoka +1990 – Nickel Ashmeade, Jamaican sprinter + 1990 – Anna Bogomazova, Russian-American kick-boxer, martial artist, and wrestler + 1990 – Sorana Cîrstea, Romanian tennis player + 1990 – Trent Cotchin, Australian footballer +1991 – Luka Milivojević, Serbian footballer + 1991 – Anne-Marie, English singer-songwriter +1992 – Andreea Acatrinei, Romanian gymnast + 1992 – Guilherme Negueba, Brazilian footballer +1993 – Ichinojō Takashi, Mongolian sumo wrestler +1994 – Johanna Allik, Estonian figure skater + 1994 – Aaron Gray, Australian rugby league player + 1994 – Josh Hader, American baseball player +1996 – Emerson Hyndman, American international soccer player +1997 – Rafaela Gómez, Ecuadorian tennis player + +Deaths + +Pre-1600 +AD 30 – Jesus Christ (possible date of the crucifixion) (b. circa 4 BC) + 821 – George the Standard-Bearer, archbishop of Mytilene (b. c. 776) + 924 – Berengar I of Italy (b. 845) +1201 – Baha al-Din Qaraqush, regent of Egypt and builder of the Cairo Citadel +1206 – Frederick I, Duke of Lorraine +1340 – Bolesław Jerzy II of Mazovia (b. 1308) +1498 – Charles VIII of France (b. 1470) +1499 – Galeotto I Pico, Duke of Mirandola (b. 1442) +1501 – Minkhaung II, king of Ava (b. 1446) + +1601–1900 +1606 – Edward Oldcorne, English martyr (b. 1561) +1614 – El Greco, Greek-Spanish painter and sculptor (b. 1541) +1638 – Shimazu Tadatsune, Japanese daimyō (b. 1576) +1651 – Lennart Torstensson, Swedish field marshal and engineer (b. 1603) +1658 – Juan Eusebio Nieremberg, Spanish mystic and philosopher (b. 1595) +1661 – Sir William Brereton, 1st Baronet, English commander and politician (b. 1604) +1663 – Francis Cooke, English-American settler (b. 1583) +1668 – William Davenant, English poet and playwright (b. 1606) +1719 – Jean-Baptiste de La Salle, French priest and saint, founded the Institute of the Brothers of the Christian Schools (b. 1651) +1739 – Dick Turpin, English criminal (b. 1705) +1747 – Leopold I, Prince of Anhalt-Dessau (b. 1676) +1761 – Thomas Bayes, English minister and mathematician (b. 1701) +1766 – Tiberius Hemsterhuis, Dutch philologist and critic (b. 1685) +1767 – Franz Sparry, Austrian composer and director (b. 1715) +1779 – Martha Ray, English singer (b.1746) +1782 – Taksin, Thai king (b. 1734) +1789 – Abdul Hamid I, Ottoman sultan (b. 1725) +1789 – Petrus Camper, Dutch physician, anatomist, and physiologist (b. 1722) +1801 – Noël François de Wailly, French lexicographer and author (b. 1724) +1804 – Toussaint Louverture, Haitian general (b. 1743) +1811 – Garsevan Chavchavadze, Georgian diplomat and politician (b. 1757) +1823 – Jacques Charles, French physicist and mathematician (b. 1746) +1833 – Antoni Radziwiłł, Lithuanian composer and politician (b. 1775) +1836 – William Godwin, English journalist and author (b. 1756) +1849 – Pedro Ignacio de Castro Barros, Argentinian priest and politician (b. 1777) +1850 – William Lisle Bowles, English poet and critic (b. 1762) +1858 – Anton Diabelli, Austrian composer and publisher (b. 1781) +1868 – Thomas D'Arcy McGee, Irish-Canadian journalist, activist, and politician (b. 1825) +1879 – Begum Hazrat Mahal, Begum of Awadh, was the second wife of Nawab Wajid Ali Shah (b. 1820) +1884 – Maria Doolaeghe, Flemish novelist (b. 1803) +1885 – Karl Theodor Ernst von Siebold, German physiologist and zoologist (b. 1804) +1889 – Youssef Bey Karam, Lebanese soldier and politician (b. 1823) + 1889 – Sebastián Lerdo de Tejada, Mexican politician and president, 1872-1876 (b. 1823) +1891 – P. T. Barnum, American businessman and politician, co-founded The Barnum & Bailey Circus (b. 1810) + +1901–present +1917 – Spyridon Samaras, Greek composer and playwright (b. 1861) +1918 – David Kolehmainen, Finnish wrestler (b. 1885) + 1918 – George E. Ohr, American potter (b. 1857) +1920 – Karl Binding, German lawyer and jurist (b. 1841) +1922 – James McGowen, Australian politician, 18th Premier of New South Wales (b. 1855) +1928 – Alexander Bogdanov, Russian physician, philosopher, and author (b. 1873) +1932 – Grigore Constantinescu, Romanian priest and journalist (b. 1875) +1938 – Suzanne Valadon, French painter (b. 1865) +1939 – Joseph Lyons, Australian educator and politician, 10th Prime Minister of Australia (b. 1879) +1943 – Jovan Dučić, Serbian-American poet and diplomat (b. 1871) + 1943 – Alexandre Millerand, French lawyer and politician, 12th President of France (b. 1859) +1947 – Henry Ford, American engineer and businessman, founded the Ford Motor Company (b. 1863) +1949 – John Gourlay, Canadian soccer player (b. 1872) +1950 – Walter Huston, Canadian-American actor and singer (b. 1883) +1955 – Theda Bara, American actress (b. 1885) +1956 – Fred Appleby, English runner (b. 1879) +1960 – Henri Guisan, Swiss general (b. 1874) +1965 – Roger Leger, Canadian ice hockey player (b. 1919) +1966 – Walt Hansgen, American race car driver (b. 1919) +1968 – Edwin Baker, Canadian co-founder of the Canadian National Institute for the Blind (CNIB) (b. 1893) + 1968 – Jim Clark, Scottish race car driver (b. 1936) +1972 – Joe Gallo, American gangster (b. 1929) + 1972 – Abeid Karume, Tanzanian politician, 1st President of Zanzibar (b. 1905) +1981 – Kit Lambert, English record producer and manager (b. 1935) + 1981 – Norman Taurog, American director and screenwriter (b. 1899) +1982 – Harald Ertl, Austrian race car driver and journalist (b. 1948) +1984 – Frank Church, American soldier, lawyer, and politician (b. 1924) +1985 – Carl Schmitt, German philosopher and jurist (b. 1888) +1986 – Leonid Kantorovich, Russian mathematician and economist (b. 1912) +1990 – Ronald Evans, American captain, engineer, and astronaut (b. 1933) +1991 – Memduh Ünlütürk, Turkish general (b. 1913) +1992 – Ace Bailey, Canadian ice hockey player and coach (b. 1903) + 1992 – Antonis Tritsis, Greek high jumper and politician, 71st Mayor of Athens (b. 1937) +1994 – Lee Brilleaux, English singer-songwriter and guitarist (b. 1952) + 1994 – Albert Guðmundsson, Icelandic footballer, manager, and politician (b. 1923) + 1994 – Golo Mann, German historian and author (b. 1909) + 1994 – Agathe Uwilingiyimana, Rwandan chemist, academic, and politician, Prime Minister of Rwanda (b. 1953) +1995 – Philip Jebb, English architect and politician (b. 1927) +1997 – Luis Aloma, Cuban-American baseball player (b. 1923) + 1997 – Georgy Shonin, Ukrainian-Russian general, pilot, and astronaut (b. 1935) +1998 – Alex Schomburg, Puerto Rican painter and illustrator (b. 1905) +1999 – Heinz Lehmann, German-Canadian psychiatrist and academic (b. 1911) +2001 – David Graf, American actor (b. 1950) + 2001 – Beatrice Straight, American actress (b. 1914) +2002 – John Agar, American actor (b. 1921) +2003 – Cecile de Brunhoff, French pianist and author (b. 1903) + 2003 – David Greene, English-American actor, director, producer, and screenwriter (b. 1921) +2004 – Victor Argo, American actor (b. 1934) + 2004 – Konstantinos Kallias, Greek politician (b. 1901) +2005 – Cliff Allison, English race car driver (b. 1932) + 2005 – Grigoris Bithikotsis, Greek singer-songwriter (b. 1922) + 2005 – Bob Kennedy, American baseball player, coach, and manager (b. 1920) + 2005 – Melih Kibar, Turkish composer and educator (b. 1951) +2007 – Johnny Hart, American author and illustrator (b. 1931) + 2007 – Barry Nelson, American actor (b. 1917) +2008 – Ludu Daw Amar, Burmese journalist and author (b. 1915) +2009 – Dave Arneson, American game designer, co-created Dungeons & Dragons (b. 1947) +2011 – Pierre Gauvreau, Canadian painter (b. 1922) +2012 – Steven Kanumba, Tanzanian actor and director (b. 1984) + 2012 – Satsue Mito, Japanese zoologist and academic (b. 1914) + 2012 – Ignatius Moses I Daoud, Syrian cardinal (b. 1930) + 2012 – David E. Pergrin, American colonel and engineer (b. 1917) + 2012 – Bashir Ahmed Qureshi, Pakistani politician (b. 1959) + 2012 – Mike Wallace, American television news journalist (b. 1918) +2013 – Marty Blake, American businessman (b. 1927) + 2013 – Les Blank, American director and producer (b. 1935) + 2013 – Andy Johns, English-American record producer (b. 1950) + 2013 – Lilly Pulitzer, American fashion designer (b. 1931) + 2013 – Irma Ravinale, Italian composer and educator (b. 1937) + 2013 – Mickey Rose, American screenwriter (b. 1935) + 2013 – Carl Williams, American boxer (b. 1959) +2014 – George Dureau, American painter and photographer (b. 1930) + 2014 – James Alexander Green, American-English mathematician and academic (b. 1926) + 2014 – V. K. Murthy, Indian cinematographer (b. 1923) + 2014 – Zeituni Onyango, Kenyan-American computer programmer (b. 1952) + 2014 – John Shirley-Quirk, English opera singer (b. 1931) + 2014 – George Shuffler, American guitarist (b. 1925) + 2014 – Josep Maria Subirachs, Spanish sculptor and painter (b. 1927) + 2014 – Royce Waltman, American basketball player and coach (b. 1942) +2015 – Tim Babcock, American soldier and politician, 16th Governor of Montana (b. 1919) + 2015 – José Capellán, Dominican-American baseball player (b. 1981) + 2015 – Stan Freberg, American puppeteer, voice actor, and singer (b. 1926) + 2015 – Richard Henyekane, South African footballer (b. 1983) + 2015 – Geoffrey Lewis, American actor (b. 1935) +2016 – Blackjack Mulligan, American professional wrestler (b. 1942) +2017 – Nicolae Șerban Tanașoca, Romanian historian and philologist (b. 1941) +2019 – Seymour Cassel, American actor (b. 1935) +2020 – John Prine, American country folk singer-songwriter (b. 1946) + 2020 – Herb Stempel, American television personality (b. 1926) +2021 – Tommy Raudonikis, Australian rugby league player and coach (b. 1950) +2023 – Ben Ferencz, American lawyer (b. 1920) + +Holidays and observances + Christian feast days: +Aibert of Crespin +Blessed Alexander Rawlins +Blessed Edward Oldcorne and Blessed Ralph Ashley +Blessed Notker the Stammerer +Brynach +Hegesippus +Henry Walpole +Hermann Joseph +Jean-Baptiste de La Salle +Patriarch Tikhon of Moscow (Eastern Orthodox Church, Episcopal Church (USA)) +April 7 (Eastern Orthodox liturgics) +Flag Day (Slovenia) +Genocide Memorial Day (Rwanda), and its related observance: +International Day of Reflection on the 1994 Rwanda Genocide (United Nations) +Motherhood and Beauty Day (Armenia) +National Beer Day (United States) +Sheikh Abeid Amani Karume Day (Tanzania) +Women's Day (Mozambique) +Veterans' Day (Belgium) +World Health Day (International observance) + +References + +External links + + BBC: On This Day + + Historical Events on April 7 + +Days of the year +April +Andalusia (, ; ) is the southernmost autonomous community in Peninsular Spain. Andalusia is located in the south of the Iberian Peninsula, in southwestern Europe. It is the most populous and the second-largest autonomous community in the country. It is officially recognised as a historical nationality and a national reality. The territory is divided into eight provinces: Almería, Cádiz, Córdoba, Granada, Huelva, Jaén, Málaga, and Seville. Its capital city is Seville. The seat of the High Court of Justice of Andalusia is located in the city of Granada. + +Andalusia is immediately south of the autonomous communities of Extremadura and Castilla-La Mancha; west of the autonomous community of Murcia and the Mediterranean Sea; east of Portugal and the Atlantic Ocean; and north of the Mediterranean Sea and the Strait of Gibraltar. Gibraltar shares a land border with the Andalusian portion of the province of Cádiz at the eastern end of the Strait of Gibraltar. + +The main mountain ranges of Andalusia are the Sierra Morena and the Baetic System, consisting of the Subbaetic and Penibaetic Mountains, separated by the Intrabaetic Basin. In the north, the Sierra Morena separates Andalusia from the plains of Extremadura and Castile–La Mancha on Spain's Meseta Central. To the south, the geographic subregion of lies mostly within the Baetic System, while is in the Baetic Depression of the valley of the Guadalquivir. + +The name "Andalusia" is derived from the Arabic word Al-Andalus (الأندلس), which in turn may be derived from the Vandals, the Goths or pre-Roman Iberian tribes. The toponym al-Andalus is first attested by inscriptions on coins minted in 716 by the new Muslim government of Iberia. These coins, called dinars, were inscribed in both Latin and Arabic. The region's history and culture have been influenced by the Tartessians, Iberians, Phoenicians, Carthaginians, Greeks, Romans, Vandals, Visigoths, Byzantines, Berbers, Arabs, Jews, Romanis and Castilians. During the Islamic Golden Age, Córdoba surpassed Constantinople to be Europe's biggest city, and became the capital of Al-Andalus and a prominent center of education and learning in the world, producing numerous philosophers and scientists. The Crown of Castile conquered and settled the Guadalquivir Valley in the 13th century. The mountainous eastern part of the region (the Kingdom of Granada) was subdued in the late 15th century. Atlantic-facing harbors prospered upon trade with the New World. Chronic inequalities in the social structure caused by uneven distribution of land property in large estates induced recurring episodes of upheaval and social unrest in the agrarian sector in the 19th and 20th centuries. + +Andalusia has historically been an agricultural region, compared to the rest of Spain and the rest of Europe. Still, the growth of the community in the sectors of industry and services was above average in Spain and higher than many communities in the Eurozone. The region has a rich culture and a strong identity. Many cultural phenomena that are seen internationally as distinctively Spanish are largely or entirely Andalusian in origin. These include flamenco and, to a lesser extent, bullfighting and Hispano-Moorish architectural styles, both of which are also prevalent in some other regions of Spain. + +Andalusia's hinterland is the hottest area of Europe, with Córdoba and Seville averaging above in summer high temperatures. These high temperatures, typical of the Guadalquivir valley (and other valleys in southern Iberia) are usually reached between 5 p.m. and 9 p.m. (local time), tempered by sea and mountain breezes afterwards. However, during heat waves late evening temperatures can locally stay around until close to midnight, and daytime highs of over are common. Also, Seville is the warmest city in continental Europe with average annual temperature of . + +Name + +Its present form is derived from the Arabic name for Muslim Iberia, "Al-Andalus". The etymology of the name "Al-Andalus" is disputed, and the extent of Iberian territory encompassed by the name has changed over the centuries. Traditionally it has been assumed to be derived from the name of the Vandals. Since the 1980s, a number of proposals have challenged this contention. Halm, in 1989, derived the name from a Gothic term, *, +and in 2002, Bossong suggested its derivation from a pre-Roman substrate. + +The Spanish place name Andalucía (immediate source of the English Andalusia) was introduced into the Spanish languages in the 13th century under the form el Andalucía. The name was adopted to refer to those territories still under Moorish rule, and generally south of Castilla Nueva and Valencia, and corresponding with the former Roman province hitherto called Baetica in Latin sources. This was a Castilianization of Al-Andalusiya, the adjectival form of the Arabic language al-Andalus, the name given by the Arabs to all of the Iberian territories under Muslim rule from 711 to 1492. The etymology of al-Andalus is itself somewhat debated (see al-Andalus), but in fact it entered the Arabic language before this area came under Moorish rule. + +Like the Arabic term al-Andalus, in historical contexts the Spanish term Andalucía or the English term Andalusia do not necessarily refer to the exact territory designated by these terms today. Initially, the term referred exclusively to territories under Muslim control. Later, it was applied to some of the last Iberian territories to be regained from the Muslims, though not always to exactly the same ones. In the Estoria de España (also known as the Primera Crónica General) of Alfonso X of Castile, written in the second half of the 13th century, the term Andalucía is used with three different meanings: + + As a literal translation of the Arabic al-Ándalus when Arabic texts are quoted. + To designate the territories the Christians had regained by that time in the Guadalquivir valley and in the Kingdoms of Granada and Murcia. In a document from 1253, Alfonso X styled himself Rey de Castilla, León y de toda Andalucía ("King of Castile, León and all of Andalusia"). + To designate the territories the Christians had regained by that time in the Guadalquivir valley until that date (the Kingdoms of Jaén, Córdoba and Seville – the Kingdom of Granada was incorporated in 1492). This was the most common significance in the Late Middle Ages and Early modern period. + +From an administrative point of view, Granada remained separate for many years even after the completion of the Reconquista due, above all, to its emblematic character as the last territory regained, and as the seat of the important Real Chancillería de Granada, a court of last resort. Still, the reconquest and repopulation of Granada was accomplished largely by people from the three preexisting Christian kingdoms of Andalusia, and Granada came to be considered a fourth kingdom of Andalusia. The often-used expression "Four Kingdoms of Andalusia" dates back in Spanish at least to the mid-18th century. + +Symbols + +The Andalusian emblem shows the figure of Hercules and two lions between the two pillars of Hercules that tradition situates on either side of the Strait of Gibraltar. An inscription below, superimposed on an image of the flag of Andalusia reads Andalucía por sí, para España y la Humanidad ("Andalusia for herself, Spain and Humanity"). Over the two columns is a semicircular arch in the colours of the flag of Andalusia, with the Latin words Dominator Hercules Fundator (Lord Hercules is the Founder) superimposed. + +The official flag of Andalusia consists of three equal horizontal stripes, coloured green, white, and green respectively; the Andalusian coat of arms is superimposed on the central stripe. Its design was overseen by Blas Infante and approved in the Assembly of Ronda (a 1918 gathering of Andalusian nationalists at Ronda). Blas Infante considered these to have been the colours most used in regional symbols throughout the region's history. According to him, the green came in particular from the standard of the Umayyad Caliphate and represented the call for a gathering of the populace. The white symbolised pardon in the Almohad dynasty, interpreted in European heraldry as parliament or peace. Other writers have justified the colours differently, with some Andalusian nationalists referring to them as the Arbonaida, meaning white-and-green in Mozarabic, a Romance language that was spoken in the region in Muslim times. Nowadays, the Andalusian government states that the colours of the flag evoke the Andalusian landscape as well as values of purity and hope for the future. + +The anthem of Andalusia was composed by José del Castillo Díaz (director of the Municipal Band of Seville, commonly known as Maestro Castillo) with lyrics by Blas Infante. The music was inspired by Santo Dios, a popular religious song sung at harvest time by peasants and day labourers in the provinces of Málaga, Seville, and Huelva. Blas Infante brought the song to Maestro Castillo's attention; Maestro Castillo adapted and harmonized the traditional melody. The lyrics appeal to the Andalusians to mobilise and demand tierra y libertad ("land and liberty") by way of agrarian reform and a statute of autonomy within Spain. + +The Parliament of Andalusia voted unanimously in 1983 that the preamble to the Statute of Autonomy recognise Blas Infante as the Father of the Andalusian Nation (Padre de la Patria Andaluza), which was reaffirmed in the reformed Statute of Autonomy submitted to popular referendum 18 February 2007. The preamble of the present 2007 Statute of Autonomy says that Article 2 of the present Spanish Constitution of 1978 recognises Andalusia as a nationality. Later, in its articulation, it speaks of Andalusia as a "historic nationality" (Spanish: nacionalidad histórica). It also cites the 1919 Andalusianist Manifesto of Córdoba describing Andalusia as a "national reality" (realidad nacional), but does not endorse that formulation. Article 1 of the earlier 1981 Statute of Autonomy defined it simply as a "nationality" (nacionalidad). + +The national holiday, Andalusia Day, is celebrated on 28 February, commemorating the 1980 autonomy referendum. + +The honorific title of Hijo Predilecto de Andalucía ("Favourite Son of Andalusia") is granted by the Autonomous Government of Andalusia to those whose exceptional merits benefited Andalusia, for work or achievements in natural, social, or political science. It is the highest distinction given by the Autonomous Community of Andalusia. + +Geography +The Sevillian historian Antonio Domínguez Ortiz wrote that: + +Location +Andalusia has a surface area of , 17.3% of the territory of Spain. Andalusia alone is comparable in extent and in the variety of its terrain to any of several of the smaller European countries. To the east is the Mediterranean Sea; to the west Portugal and the Gulf of Cádiz (Atlantic Ocean); to the north the Sierra Morena constitutes the border with the Meseta Central; to the south, the self-governing British overseas territory of Gibraltar and the Strait of Gibraltar separate it from Morocco. + +Climate + +Andalusia is home to the hottest and driest climates in Spain, with yearly average rainfall around in Cabo de Gata, as well as some of the wettest ones, with yearly average rainfall above in inland Cádiz. In the west, weather systems sweeping in from the Atlantic ensure that it is relatively wet and humid in the winter, with some areas receiving copious amounts. Contrary to what many people think, as a whole, the region enjoys above-average yearly rainfall in the context of Spain. + +Andalusia sits at a latitude between 36° and 38° 44' N, in the warm-temperate region. In general, it experiences a hot-summer Mediterranean climate, with dry summers influenced by the Azores High, but subject to occasional torrential rains and extremely hot temperatures. In the winter, the tropical anticyclones move south, allowing cold polar fronts to penetrate the region. Still, within Andalusia there is considerable climatic variety. From the extensive coastal plains one may pass to the valley of the Guadalquivir, barely above sea level, then to the highest altitudes in the Iberian peninsula in the peaks of the Sierra Nevada. In a mere one can pass from the subtropical coast of the province of Granada to the snowy peaks of Mulhacén. Andalusia also includes both the dry Tabernas Desert in the province of Almería and the Sierra de Grazalema Natural Park in the province of Cádiz, which experiences Spain's greatest rainfall. + +Annual rainfall in the Sierra de Grazalema has been measured as high as in 1963, the highest ever recorded for any location in Iberia. Andalusia is also home to the driest place in continental Europe, the Cabo de Gata, with only of rain per year. + +In general, as one goes from west to east, away from the Atlantic, there is less precipitation. "Wet Andalusia" includes most of the highest points in the region, above all the Sierra de Grazalema but also the Serranía de Ronda in western Málaga. The valley of the Guadalquivir has moderate rainfall. The Tabernas Desert in Almería, Europe's only true desert, has less than 75 days with any measurable precipitation, and some particular places in the desert have as few as 50 such days. Much of "dry Andalusia" has more than 300 sunny days a year. + +The average temperature in Andalusia throughout the year is over . Averages in the cities range from in Baeza to in Almería. Much of the Guadalquivir valley and the Mediterranean coast has an average of about . The coldest month is January when Granada at the foot of the Sierra Nevada experiences an average temperature of . The hottest are July and August, with an average temperature of for Andalusia as a whole. Córdoba is the hottest provincial capital, followed by Seville. + +The Guadalquivir valley has experienced some of the highest temperatures recorded in Europe, with a maximum of recorded at Córdoba (14 August 2021), and Seville. The mountains of Granada and Jaén have the coldest temperatures in southern Iberia, but do not reach continental extremes (and, indeed are surpassed by some mountains in northern Spain). In the cold snap of January 2005, Santiago de la Espada (Jaén) experienced a temperature of and the ski resort at Sierra Nevada National Park—the southernmost ski resort in Europe—dropped to . Sierra Nevada Natural Park has Iberia's lowest average annual temperature, ( at Pradollano) and its peaks remain snowy practically year-round. + +Terrain + +Mountain ranges affect climate, the network of rivers, soils and their erosion, bioregions, and even human economies insofar as they rely on natural resources. The Andalusian terrain offers a range of altitudes and slopes. Andalusia has the Iberian peninsula's highest mountains and nearly 15 percent of its terrain over . The picture is similar for areas under (with the Baetic Depression), and for the variety of slopes. + +The Atlantic coast is overwhelmingly beach and gradually sloping coasts; the Mediterranean coast has many cliffs, above all in the Malagan Axarquía and in Granada and Almería. This asymmetry divides the region naturally into (two mountainous areas) and (the broad basin of the Guadalquivir). + +The Sierra Morena separates Andalusia from the plains of Extremadura and Castile–La Mancha on Spain's Meseta Central. Although sparsely populated, this is not a particularly high range, and its highest point, the peak of La Bañuela in the Sierra Madrona, lies outside of Andalusia. Within the Sierra Morena, the gorge of Despeñaperros forms a natural frontier between Castile and Andalusia. + +The Baetic Cordillera consists of the parallel mountain ranges of the Cordillera Penibética near the Mediterranean coast and the Cordillera Subbética inland, separated by the Surco Intrabético. The Cordillera Subbética is quite discontinuous, offering many passes that facilitate transportation, but the Penibético forms a strong barrier between the Mediterranean coast and the interior. The Sierra Nevada, part of the Cordillera Penibética in the Province of Granada, has the highest peaks in Iberia: El Mulhacén at and El Veleta at . + +Lower Andalusia, the Baetic Depression, the basin of the Guadalquivir, lies between these two mountainous areas. It is a nearly flat territory, open to the Gulf of Cádiz in the southeast. Throughout history, this has been the most populous part of Andalusia. + +Hydrography + +Andalusia has rivers that flow into both the Atlantic and the Mediterranean. Flowing to the Atlantic are the Guadiana, Odiel-Tinto, Guadalquivir, Guadalete, and Barbate. Flowing to the Mediterranean are the Guadiaro, Guadalhorce, Guadalmedina, Guadalfeo, Andarax (also known as the Almería) and Almanzora. Of these, the Guadalquivir is the longest in Andalusia and fifth longest on the Iberian peninsula, at . + +The rivers of the Atlantic basin are characteristically long, run through mostly flat terrain, and have broad river valleys. As a result, at their mouths are estuaries and wetlands, such as the marshes of Doñana in the delta of the Guadalquivir, and wetlands of the Odiel. In contrast, the rivers of the Mediterranean Basin are shorter, more seasonal, and make a precipitous descent from the mountains of the Baetic Cordillera. Their estuaries are small, and their valleys are less suitable for agriculture. Also, being in the rain shadow of the Baetic Cordillera means that they receive a lesser volume of water. + +The following hydrographic basins can be distinguished in Andalusia. On the Atlantic side are the Guadalquivir basin; the Andalusian Atlantic Basin with the sub-basins Guadalete-Barbate and Tinto-Odiel; and the Guadiana basin. On the Mediterranean side is the Andalusian Mediterranean Basin and the upper portion of the basin of the Segura. + +Soils +The soils of Andalusia can be divided into three large areas: the Sierra Morena, Cordillera Subbética, and the Baetic Depression and the Surco Intrabético. + +The Sierra Morena, due to its morphology and the acidic content of its rocks, developed principally relatively poor, shallow soils, suitable only for forests. In the valleys and in some areas where limestone is present, deeper soils allowed farming of cereals suitable for livestock. The more complicated morphology of the Baetic Cordillera makes it more heterogeneous, with the most heterogeneous soils in Andalusia. Very roughly, in contrast to the Sierra Morena, a predominance of basic (alkaline) materials in the Cordillera Subbética, combined with a hilly landscape, generates deeper soils with greater agricultural capacity, suitable to the cultivation of olives. + +Finally, the Baetic Depression and the Surco Intrabético have deep, rich soils, with great agricultural capacity. In particular, the alluvial soils of the Guadalquivir valley and plain of Granada have a loamy texture and are particularly suitable for intensive irrigated crops. In the hilly areas of the countryside, there is a double dynamic: the depressions have filled with older lime-rich material, developing the deep, rich, dark clay soils the Spanish call bujeo, or tierras negras andaluzas, excellent for dryland farming. In other zones, the whiter albariza provides an excellent soil for vineyards. + +Despite their marginal quality, the poorly consolidated soils of the sandy coastline of Huelva and Almería have been successfully used in recent decades for hothouse cultivation under clear plastic of strawberries, raspberries, blueberries, and other fruits. + +Flora + +Biogeographically, Andalusia forms part of the Western Mediterranean subregion of the Mediterranean Basin, which falls within the Boreal Kingdom. Five floristic provinces lie, in whole or in part, within Andalusia: along much of the Atlantic coast, the Lusitanian-Andalusian littoral or Andalusian Atlantic littoral; in the north, the southern portion of the Luso-Extremaduran floristic province; covering roughly half of the region, the Baetic floristic province; and in the extreme east, the Almerian portion of the Almerian-Murcian floristic province and (coinciding roughly with the upper Segura basin) a small portion of the Castilian-Maestrazgan-Manchegan floristic province. These names derive primarily from past or present political geography: "Luso" and "Lusitanian" from Lusitania, one of three Roman provinces in Iberia, most of the others from present-day Spanish provinces, and Maestrazgo being a historical region of northern Valencia. + +In broad terms, the typical vegetation of Andalusia is Mediterranean woodland, characterized by leafy xerophilic perennials, adapted to the long, dry summers. The dominant species of the climax community is the holly oak (Quercus ilex). Also abundant are cork oak (Quercus suber), various pines, and Spanish fir (Abies pinsapo). Due to cultivation, olive (Olea europaea) and almond (Prunus dulcis) trees also abound. The dominant understory is composed of thorny and aromatic woody species, such as rosemary (Rosmarinus officinalis), thyme (Thymus), and Cistus. In the wettest areas with acidic soils, the most abundant species are the oak and cork oak, and the cultivated Eucalyptus. In the woodlands, leafy hardwoods of genus Populus (poplars, aspens, cottonwoods) and Ulmus (elms) are also abundant; poplars are cultivated in the plains of Granada. + +The Andalusian woodlands have been much altered by human settlement, the use of nearly all of the best land for farming, and frequent wildfires. The degraded forests become shrubby and combustible garrigue. Extensive areas have been planted with non-climax trees such as pines. There is now a clear conservation policy for the remaining forests, which survive almost exclusively in the mountains. + +Fauna + +The biodiversity of Andalusia extends to its fauna as well. More than 400 of the 630 vertebrate species extant in Spain can be found in Andalusia. Spanning the Mediterranean and Atlantic basins, and adjacent to the Strait of Gibraltar, Andalusia is on the migratory route of many of the numerous flocks of birds that travel annually from Europe to Africa and back. + +The Andalusian wetlands host a rich variety of birds. Some are of African origin, such as the red-knobbed coot (Fulica cristata), the purple swamphen (Porphyrio porphyrio), and the greater flamingo (Phoenicopterus roseus). Others originate in Northern Europe, such as the greylag goose (Anser anser). Birds of prey (raptors) include the Spanish imperial eagle (Aquila adalberti), the griffon vulture (Gyps fulvus), and both the black and red kite (Milvus migrans and Milvus milvus). + +Among the herbivores, are several deer (Cervidae) species, notably the fallow deer (Dama dama) and roe deer (Capreolus capreolus); the European mouflon (Ovis aries musimon), a feral sheep; and the Spanish ibex (Capra pyrenaica, which despite its scientific name is no longer found in the Pyrenees). The Spanish ibex has recently been losing ground to the Barbary sheep (Ammotragus lervia), an invasive species from Africa, introduced for hunting in the 1970s. Among the small herbivores are rabbits—especially the European rabbit (Oryctolagus cuniculus)—which form the most important part of the diet of the carnivorous species of the Mediterranean woodlands. + +The large carnivores such as the Iberian wolf (Canis lupus signatus) and the Iberian lynx (Lynx pardinus) are quite threatened, and are limited to the Sierra de Andújar, inside of Sierra Morena, Doñana and Despeñaperros. Stocks of the wild boar (Sus scrofa), on the other hand, have been well preserved because they are popular with hunters. More abundant and in varied situations of conservation are such smaller carnivores as otters, dogs, foxes, the European badger (Meles meles), the European polecat (Mustela putorius), the least weasel (Mustela nivalis), the European wildcat (Felis silvestris), the common genet (Genetta genetta), and the Egyptian mongoose (Herpestes ichneumon). + +Other notable species are Acherontia atropos (a variety of death's-head hawkmoth), Vipera latasti (a venomous snake), and the endemic (and endangered) fish Aphanius baeticus. + +Protected areas + +Andalusia has many unique ecosystems. In order to preserve these areas in a manner compatible with both conservation and economic exploitation, many of the most representative ecosystems have been given protected status. + +The various levels of protection are encompassed within the Network of Protected Natural Spaces of Andalusia (Red de Espacios Naturales Protegidos de Andalucía, RENPA) which integrates all protected natural spaces located in Andalusia, whether they are protected at the level of the local community, the autonomous community of Andalusia, the Spanish state, or by international conventions. RENPA consists of 150 protected spaces, consisting of two national parks, 24 natural parks, 21 periurban parks (on the fringes of cities or towns), 32 natural sites, two protected countrysides, 37 natural monuments, 28 nature reserves, and four concerted nature reserves (in which a government agency coordinates with the owner of the property for its management), all part of the European Union's Natura 2000 network. Under the international ambit are the nine Biosphere Reserves, 20 Ramsar wetland sites, four Specially Protected Areas of Mediterranean Importance and two UNESCO Geoparks. + +In total, nearly 20 percent of the territory of Andalusia lies in one of these protected areas, which constitute roughly 30 percent of the protected territory of Spain. Among these many spaces, some of the most notable are the Sierras de Cazorla, Segura y Las Villas Natural Park, Spain's largest natural park and the second largest in Europe, the Sierra Nevada National Park, Doñana National Park and Natural Park, the Tabernas Desert, and the Cabo de Gata-Níjar Natural Park, the largest terrestrial-maritime reserve in the European Western Mediterranean Sea. + +History + +The geostrategic position of Andalusia in the extreme south of Europe, providing (along with Morocco) a gateway between Europe and Africa, added to its position between the Atlantic Ocean and the Mediterranean Sea, as well as its rich deposits of minerals and its agricultural wealth, have made Andalusia a tempting prize for civilizations since prehistoric times. Add to this its area of (larger than many European countries), and it can be no surprise that Andalusia has figured prominently in the history of Europe and the Mediterranean. + +Several theories postulate that the first hominids in Europe were in Andalusia, having passed across the Strait of Gibraltar; the earliest known paintings of humanity have been found in the Caves of Nerja, Málaga. The first settlers, based on artifacts from the archaeological sites at Los Millares, El Argar, and Tartessos, were clearly influenced by cultures of the Eastern Mediterranean who arrived on the Andalusian coast. Andalusia then went through a period of protohistory, when the region did not have a written language of its own, but its existence was known to and documented by literate cultures, principally the Phoenicians and Ancient Greeks, wide historical moment in which Cádiz was founded, regarded by many as the oldest city still standing in Western Europe; another city among the oldest is Málaga. During the second millennium BCE, the kingdom of Tartessos developed in Andalusia. + +Carthaginians and Romans + +With the fall of the original Phoenician cities in the East, Carthage – itself the most significant Phoenician colony – became the dominant sea power of the western Mediterranean and the most important trading partner for the Phoenician towns along the Andalusian coast. Between the First and Second Punic Wars, Carthage extended its control beyond Andalucia to include all of Iberia except the Basque Country. Some of the more prominent Andalusian cities during Carthaginian rule include Gadir (Cadiz), Qart Juba (Córdoba), Ilipa (near modern Seville), Malaka (Málaga) and Sexi or Seksi (near modern Almuñécar). Andalusia was the major staging ground for the war with Rome led by the Carthaginian general Hannibal. The Romans defeated the Carthaginians and conquered Andalusia, the region being renamed Baetica. It was fully incorporated into the Roman Empire, and from this region came many Roman magistrates and senators, as well as the emperors Trajan and (most likely) Hadrian. + +Vandals, Visigoths and the Byzantine Empire +The Vandals moved briefly through the region during the 5th century AD before settling in North Africa, after which the region fell into the hands of the Visigothic Kingdom. The Visigoths in this region were practically independent of the Visigothic Catholic Kingdom of Toledo. This is the era of Saints Isidore of Seville and Hermenegild. During this period, around 555 AD, the Eastern Roman Empire conquered Andalusia under Justinian I, the Eastern Roman emperor. They established Spania, a province of the Byzantine Empire from 552 until 624. Although their holdings were quickly reduced, they continued to have interests in the region until it was lost altogether in 624. + +Al-Andalus states + +The Visigothic era came to an abrupt end in 711 with the Umayyad conquest of Hispania by the Muslim Umayyad general Tariq ibn Ziyad. Tariq is known in Umayyad history and legend as a formidable conqueror who burned his fleet of ships when he landed with his troops on the coast of Gibraltar – an acronym of "Jabel alTariq" meaning "the mountain of Tariq". When the Muslim invaders seized control and consolidated their dominion of the region, they remained tolerant of the local faiths, but they also needed a place for their own faith. In the 750s, they forcibly rented half of Córdoba 's Cathedral of San Vicente (Visigothic) to use as a mosque. + + The mosque's hypostyle plan, consisting of a rectangular prayer hall and an enclosed courtyard, followed a tradition established in the Umayyad and Abbasid mosques of Syria and Iraq while the dramatic articulation of the interior of the prayer hall was unprecedented. The system of columns supporting double arcades of piers and arches with alternating red and white voussoirs is an unusual treatment that, structurally, combined striking visual effect with the practical advantage of providing greater height within the hall. Alternating red and white voussoirs are associated with Umayyad monuments such as the Great Mosque of Damascus and the Dome of the Rock. Their use in the Great Mosque of Córdoba manages to create a stunningly original visual composition even as it emphasises 'Abd al-Rahman's connection to the established Umayyad tradition. + +In this period, the name "Al-Andalus" was applied to the Iberian Peninsula, and later it referred to the parts not controlled by the Gothic states in the North. The Muslim rulers in Al-Andalus were economic invaders and interested in collecting taxes; social changes imposed on the native populace were mainly confined to geographical, political and legal conveniences. Al-Andalus remained connected to other states under Muslim rule; also trade routes between it and Constantinople and Alexandria remained open, while many cultural features of the Roman Empire were transmitted throughout Europe and the Near East by its successor state, the Byzantine Empire. Byzantine architecture is an example of such cultural diffusion continuing even after the collapse of the empire. + +Nevertheless, the Guadalquivir River valley became the point of power projection in the peninsula with the Caliphate of Córdoba making Córdoba its capital. The Umayyad Caliphate produced such leaders as Caliph Abd-ar-Rahman III (ruled 912–961) and his son, Caliph Al-Hakam II (ruled 961–976) and built the magnificent Great Mosque of Córdoba. Under these rulers, Córdoba was the center of economic and cultural significance. + +By the 10th century, the northern Kingdoms of Spain and other European Crowns had begun what would eventually become the Reconquista: the reconquest of the Iberian Peninsula for Christendom. Caliph Abd-ar-Rahman suffered some minor military defeats, but often managed to manipulate the Gothic northern kingdoms to act against each other's interests. Al-Hakam achieved military successes, but at the expense of uniting the north against him. In the 10th century the Saracen rulers of Andalusia had a Slavic army of 13,750 men. + +After the conquest of Toledo in 1086 by Alfonso VI, the Crown of Castille and the Crown of Aragon dominated large parts of the peninsula. The main Taifas therefore had to resort to assistance from various other powers across the Mediterranean. A number of different Muslim dynasties of North African origin—notably Almoravid dynasty and Almohad dynasty—dominated a slowly diminishing Al-Andalus over the next several centuries. + +After the victory at the Battle of Sagrajas (1086) put a temporary stop to Castilian expansion, the Almoravid dynasty reunified Al-Andalus with its capital in Córdoba, ruling until the mid-12th century. The various Taifa kingdoms were assimilated. the Almohad dynasty expansion in North Africa weakened Al-Andalus, and in 1170 the Almohads transferred their capital from Marrakesh to Seville. The victory at the Battle of Las Navas de Tolosa (1212) marked the beginning of the end of the Almohad dynasty. + +Crown of Castile +The weakness caused by the collapse of Almohad power and the subsequent creation of new Taifas, each with its own ruler, led to the rapid Castile reconquest of the valley of the Guadalquivir. Córdoba was regained in 1236 and Seville in 1248. The fall of Granada on 2 January 1492 put an end to the Nasrid rule; an event that marks the beginning of Andalusia, the southern four territories of the Crown of Castile in the Iberian Peninsula. + +Seven months later, on 3 August 1492 Christopher Columbus left the town of Palos de la Frontera, Huelva, with the first expedition that resulted in the Discovery of the Americas, that would end the Middle Ages and signal the beginning of modernity. Many Castilians participated in this and other expeditions that followed, some of them known as the Minor or Andalusian Journeys. + +Contacts between Spain and the Americas, including royal administration and the shipping trade from Asia and America for over three hundred years, came almost exclusively through the south of Spain, specially Seville and Cadiz ports. + +As a result, it became the wealthiest, most influential region in Spain and amongst the most influential in Europe. For example, the Habsburg diverted much of this trade wealth to control its European territories. + +Habsburg Spain +In the first half of the 16th century plague was still prevalent in Spain. According to George C. Kohn, "One of the worst epidemics of the century, whose miseries were accompanied by severe drought and food shortage, started in 1505; by 1507, about 100,000 people had died in Andalusia alone. Andalusia was struck once again in 1646. For three years, plague haunted the entire region, causing perhaps as many as 200,000 deaths, especially in Málaga and Seville." + +A second insurrection, the Morisco Revolt (1568–1571), ensued in the Kingdom of Granada. It was crushed and the demographics of the kingdom of Granada was hammered, with the Morisco population decreasing in number by more than 100,000 including deaths, flights and deportations, contrasting with the less than 40,000 number of incoming settlers. + +In 1810–12 Spanish troops strongly resisted the French occupation during the Peninsular War (part of the Napoleonic Wars). + +Andalusia profited from the Spanish overseas empire, although much trade and finance eventually came to be controlled by other parts of Europe to where it was ultimately destined. In the 18th century, commerce from other parts of Spain began to displace Andalusian commerce when the Spanish government ended Andalusia's trading monopoly with the colonies in the Americas. The loss of the empire in the 1820s hurt the economy of the region, particularly the cities that had benefited from the trade and ship building. The construction of railways in the latter part of the 19th century enabled Andalusia to better develop its agricultural potential and it became an exporter of food. While industrialisation was taking off in the northern Spanish regions of Catalonia and the Basque country, Andalusia remained traditional and displayed a deep social division between a small class of wealthy landowners and a population made up largely of poor agricultural labourers and tradesmen. + +Francoist oppressions + +Andalusia was one of the worst affected regions of Spain by Francisco Franco's brutal campaign of mass-murder and political suppression called the White Terror during and after the Spanish Civil War. The Nationalist rebels bombed and seized the working-class districts of the main Andalusian cities in the first days of the war, and afterwards went on to execute thousands of workers and militants of the leftist parties: in the city of Córdoba 4,000; in the city of Granada 5,000; in the city of Seville 3,028; and in the city of Huelva 2,000 killed and 2,500 disappeared. The city of Málaga, occupied by the Nationalists in February 1937 following the Battle of Málaga, experienced one of the harshest repressions following Francoist victory with an estimated total of 17,000 people summarily executed. Carlos Arias Navarro, then a young lawyer who as public prosecutor signed thousands of execution warrants in the trials set up by the triumphant rightists, became known as "The Butcher of Málaga" (Carnicero de Málaga). + +Paul Preston estimates the total number of victims of deliberately killed by the Nationalists in Andalusia at 55,000. + +Government and politics + +Andalusia is one of the 17 autonomous communities of Spain. The Regional Government of Andalusia (Spanish: Junta de Andalucía) includes the Parliament of Andalusia, its chosen president, a Consultative Council, and other bodies. + +The Autonomous Community of Andalusia was formed in accord with a referendum of 28 February 1980 and became an autonomous community under the 1981 Statute of Autonomy known as the Estatuto de Carmona. The process followed the Spanish Constitution of 1978, still current as of 2009, which recognizes and guarantees the right of autonomy for the various regions and nationalities of Spain. The process to establish Andalusia as an autonomous region followed Article 151 of the Constitution, making Andalusia the only autonomous community to take that particular course. That article was set out for regions like Andalusia that had been prevented by the outbreak of the Spanish Civil War from adopting a statute of autonomy during the period of the Second Spanish Republic. + +Article 1 of the 1981 Statute of Autonomy justifies autonomy based on the region's "historical identity, on the self-government that the Constitution permits every nationality, on outright equality to the rest of the nationalities and regions that compose Spain, and with a power that emanates from the Andalusian Constitution and people, reflected in its Statute of Autonomy". + +In October 2006 the constitutional commission of the Cortes Generales (the national legislature of Spain), with favorable votes from the left-of-center Spanish Socialist Workers' Party (PSOE), the leftist United Left (IU) and the right-of-center People's Party (PP), approved a new Statute of Autonomy for Andalusia, whose preamble refers to the community as a "national reality" (realidad nacional): + +On 2 November 2006 the Spanish Chamber Deputies ratified the text of the Constitutional Commission with 306 votes in favor, none opposed, and 2 abstentions. This was the first time a Spanish Organic Law adopting a Statute of Autonomy was approved with no opposing votes. The Senate, in a plenary session of 20 December 2006, ratified the referendum to be voted upon by the Andalusian public 18 February 2007. + +The Statute of Autonomy spells out Andalusia's distinct institutions of government and administration. Chief among these is the Andalusian Autonomous Government (Junta de Andalucía). Other institutions specified in the Statute are the Defensor del Pueblo Andaluz (literally "Defender of the Andalusian People", basically an ombudsperson), the Consultative Council, the Chamber of Accounts, the Audiovisual Council of Andalusia, and the Economic and Social Council. + +The Andalusian Statute of Autonomy recognizes Seville as the autonomy's capital. The Andalusian Autonomous Government is located there. The region's highest court, the High Court of Andalusia (Tribunal Superior de Justicia de Andalucía) is not part of the Autonomous Government, and has its seat in Granada. + +Autonomous Government + +The Andalusian Autonomous Government (Junta de Andalucía) is the institution of self-government of the Autonomous Community of Andalusia. Within the government, the President of Andalusia is the supreme representative of the autonomous community, and the ordinary representative of the Spanish state in the autonomous community. The president is formally named to the position by the Monarch of Spain and then confirmed by a majority vote of the Parliament of Andalusia. In practice, the monarch always names a person acceptable to the ruling party or coalition of parties in the autonomous region. In theory, were the candidate to fail to gain the needed majority, the monarch could propose a succession of candidates. After two months, if no proposed candidate could gain the parliament's approval, the parliament would automatically be dissolved and the acting president would call new elections. On 18 January 2019 Juan Manuel Moreno was elected as the sixth president of Andalusia. + +The Council of Government, the highest political and administrative organ of the Community, exercises regulatory and executive power. The President presides over the council, which also includes the heads of various departments (Consejerías). In the current legislature (2008–2012), there are 15 of these departments. In order of precedence, they are Presidency, Governance, Economy and Treasury, Education, Justice and Public Administration, Innovation, Science and Business, Public Works and Transportation, Employment, Health, Agriculture and Fishing, Housing and Territorial Planning, Tourism, Commerce and Sports, Equality and Social Welfare, Culture, and Environment. + +The Parliament of Andalusia, its Autonomic Legislative Assembly, develops and approves laws and elects and removes the President. Elections to the Andalusian Parliament follow a democratic formula through which the citizens elect 109 representatives. After the approval of the Statute of Autonomy through Organic Law 6/1981 on 20 December 1981, the first elections to the autonomic parliament took place 23 May 1982. Further elections have occurred in 1986, 1990, 1994, 1996, 2000, 2004, and 2008. + +The current (2008–2012) legislature includes representatives of the PSOE-A (Andalusian branch of the left-of-center PSOE), PP-A (Andalusian branch of the right-of-center PP) and IULV-CA (Andalusian branch of the leftist IU). + +Judicial power +The High Court of Andalusia (Tribunal Superior de Justicia de Andalucía) in Granada is subject only to the higher jurisdiction of the Supreme Court of Spain. The High Court is not an organ of the Autonomous Community, but rather of the Judiciary of Spain, which is unitary throughout the kingdom and whose powers are not transferred to the autonomous communities. The Andalusian territory is divided into 88 legal/judicial districts (partidos judiciales). + +Administrative divisions + +Provinces + +Andalusia consists of eight provinces. The latter were established by Javier de Burgos in the 1833 territorial division of Spain. Each of the Andalusian provinces bears the same name as its capital: + +Andalusia is traditionally divided into two historical subregions: or (Andalucía Oriental), consisting of the provinces of Almería, Granada, Jaén, and Málaga, and or (Andalucía Occidental), consisting of the provinces of Cádiz, Córdoba, Huelva and Seville. + +Comarcas and mancomunidades + +Within the various autonomous communities of Spain, comarcas are comparable to shires (or, in some countries, counties) in the English-speaking world. Unlike in some of Spain's other autonomous communities, under the original 1981 Statute of Autonomy, the comarcas of Andalusia had no formal recognition, but, in practice, they still had informal recognition as geographic, cultural, historical, or in some cases administrative entities. The 2007 Statute of Autonomy echoes this practice, and mentions comarcas in Article 97 of Title III, which defines the significance of comarcas and establishes a basis for formal recognition in future legislation. + +The current statutory entity that most closely resembles a comarca is the , a freely chosen, bottom-up association of municipalities intended as an instrument of socioeconomic development and coordination between municipal governments in specific areas. + +Municipalities and local entities + +Beyond the level of provinces, Andalusia is further divided into 774 municipalities (municipios). The municipalities of Andalusia are regulated by Title III of the Statute of Autonomy, Articles 91–95, which establishes the municipality as the basic territorial entity of Andalusia, each of which has legal personhood and autonomy in many aspects of its internal affairs. At the municipal level, representation, government and administration is performed by the ayuntamiento (municipal government), which has competency for urban planning, community social services, supply and treatment of water, collection and treatment of waste, and promotion of tourism, culture, and sports, among other matters established by law. + +Among the more important Andalusian cities besides the provincial capitals are: + El Ejido, Níjar and Roquetas de Mar (Almería) + La Línea de la Concepción, Algeciras, Sanlúcar de Barrameda, San Fernando, Chiclana de la Frontera, Puerto Real, Arcos de la Frontera, Jerez and El Puerto de Santa María (Cádiz) + Lucena, Pozoblanco, Montilla and Puente Genil (Córdoba) + Almuñécar, Guadix, Loja and Motril (Granada) + Linares, Andújar, Úbeda and Baeza (Jaén) + Marbella, Mijas, Vélez-Málaga, Fuengirola, Torremolinos, Estepona, Benalmádena, Antequera, Rincón de la Victoria and Ronda (Málaga) + Utrera, Dos Hermanas, Alcalá de Guadaíra, Osuna, Mairena del Aljarafe, Écija and Lebrija (Sevilla) + +In conformity with the intent to devolve control as locally as possible, in many cases, separate nuclei of population within municipal borders each administer their own interests. These are variously known as pedanías ("hamlets"), villas ("villages"), aldeas (also usually rendered as "villages"), or other similar names. + +Main cities + +Demographics +Andalusia ranks first by population among the 17 autonomous communities of Spain. The estimated population at the beginning of 2009 was 8,285,692. The population is concentrated, above all, in the provincial capitals and along the coasts, so that the level of urbanization is quite high; half the population is concentrated in the 28 cities of more than 50,000 inhabitants. The population is aging, although the process of immigration is countering the inversion of the population pyramid. + +Population change + +At the end of the 20th century, Andalusia was in the last phase of demographic transition. The death rate stagnated at around 8–9 per thousand, and the population came to be influenced mainly by birth and migration. +In 1950, Andalusia had 20.04 percent of the national population of Spain. By 1981, this had declined to 17.09 percent. Although the Andalusian population was not declining in absolute terms, these relative losses were due to emigration great enough to nearly counterbalance having the highest birth rate in Spain. Since the 1980s, this process has reversed on all counts, and as of 2009, Andalusia has 17.82 percent of the Spanish population. +The birth rate is sharply down, as is typical in developed economies, although it has lagged behind much of the rest of the world in this respect. Furthermore, prior emigrants have been returning to Andalusia. Beginning in the 1990s, others have been immigrating in large numbers as well, as Spain has become a country of net immigration. + +At the beginning of the 21st century, statistics show a slight increase in the birth rate, due in large part to the higher birth rate among immigrants. The result is that as of 2009, the trend toward rejuvenation of the population is among the strongest of any autonomous community of Spain, or of any comparable region in Europe. + +Structure + +At the beginning of the 21st century, the population structure of Andalusia shows a clear inversion of the population pyramid, with the largest cohorts falling between ages 25 and 50. Comparison of the population pyramid in 2008 to that in 1986 shows: + A clear decrease in the population under the age of 25, due to a declining birth rate. + An increase in the adult population, as the earlier, larger cohort born in the "baby boom" of the 1960s and 1970s reach adulthood. This effect has been exacerbated by immigration: the largest contingent of immigrants are young adults. + A further increase in the adult population, and especially the older adult population, due to increased life expectancy. + +As far as composition by sex, two aspects stand out: the higher percentage of women in the elderly population, owing to women's longer life expectancy, and, on the other hand, the higher percentage of men of working age, due in large part to a predominantly male immigrant population. + +Immigration +In 2005, 5.35 percent of the population of Andalusia were born outside of Spain. This is a relatively low number for a Spanish region, the national average being three percentage points higher. The immigrants are not evenly distributed among the Andalusian provinces: Almería, with a 15.20 percent immigrant population, is third among all provinces in Spain, while at the other extreme Jaén is only 2.07 percent immigrants and Córdoba 1.77 percent. The predominant nationalities among the immigrant populations are Moroccan (92,500, constituting 17.79 percent of the foreigners living in Andalusia) and British (15.25 percent across the region). When comparing world regions rather than individual countries, the single largest immigrant block is from the region of Latin America, outnumbering not only all North Africans, but also all non-Spanish Western Europeans. Demographically, this group has provided an important addition to the Andalusian labor force. + +Economy +Andalusia is traditionally an agricultural area, but the service sector (particularly tourism, retail sales, and transportation) now predominates. The once booming construction sector, hit hard by the 2009 recession, was also important to the region's economy. The industrial sector is less developed than most other regions in Spain. + +Between 2000 and 2006 economic growth per annum was 3.72%, one of the highest in the country. Still, according to the Spanish (INE), the GDP per capita of Andalusia (€17,401; 2006) remains the second lowest in Spain, with only Extremadura lagging behind. The Gross domestic product (GDP) of the autonomous community was 160.6 billion euros in 2018, accounting for 13.4% of Spanish economic output. GDP per capita adjusted for purchasing power was 20,500 euros or 68% of the EU27 average in the same year. + +Primary sector +The primary sector, despite adding the least of the three sectors to the regional GDP remains important, especially when compared to typical developed economies. The primary sector produces 8.26 percent of regional GDP, 6.4 percent of its GVA and employs 8.19 percent of the workforce. In monetary terms it could be considered a rather uncompetitive sector, given its level of productivity compared to other Spanish regions. In addition to its numeric importance relative to other regions, agriculture and other primary sector activities have strong roots in local culture and identity. + +The primary sector is divided into a number of subsectors: agriculture, commercial fishing, animal husbandry, hunting, forestry, mining, and energy. + +Agriculture, husbandry, hunting, and forestry + +For many centuries, agriculture dominated Andalusian society, and, with 44.3 percent of its territory cultivated and 8.4 percent of its workforce in agriculture as of 2016 it remains an integral part of Andalusia's economy. However, its importance is declining, like the primary and secondary sectors generally, as the service sector is increasingly taking over. The primary cultivation is dryland farming of cereals and sunflowers without artificial irrigation, especially in the vast countryside of the Guadalquivir valley and the high plains of Granada and Almería-with a considerably lesser and more geographically focused cultivation of barley and oats. Using irrigation, maize, cotton and rice are also grown on the banks of the Guadalquivir and Genil. + +The most important tree crops are olives, especially in the Subbetic regions of the provinces of Córdoba and Jáen, where irrigated olive orchards constitute a large component of agricultural output. There are extensive vineyards in various zones such as Jerez de la Frontera (sherry), Condado de Huelva, Montilla-Moriles and Málaga. Fruits—mainly citrus fruits—are grown near the banks of the Guadalquivir; almonds, which require far less water, are grown on the high plains of Granada and Almería. + +In monetary terms, by far the most productive and competitive agriculture in Andalusia is the intensive forced cultivation of strawberries, raspberries, blueberries, and other fruits grown under hothouse conditions under clear plastic, often in sandy zones, on the coasts, in Almería and Huelva. + +Organic farming has recently undergone rapid expansion in Andalusia, mainly for export to European markets but with increasing demand developing in Spain. + +Andalusia has a long tradition of animal husbandry and livestock farming, but it is now restricted mainly to mountain meadows, where there is less pressure from other potential uses. Andalusians have a long and colourful history of dog breeding that can be observed throughout the region today. The raising of livestock now plays a semi-marginal role in the Andalusian economy, constituting only 15 percent of the primary sector, half the number for Spain taken as a whole. + +"Extensive" raising of livestock grazes the animals on natural or cultivated pastures, whereas "intensive" raising of livestock is based in fodder rather than pasture. Although the productivity is higher than with extensive techniques, the economics are quite different. While intensive techniques now dominate in Europe and even in other regions of Spain, most of Andalusia's cattle, virtually all of its sheep and goats, and a good portion of its pigs are raised by extensive farming in mountain pastures. This includes the Black Iberian pigs that are the source of Jamón ibérico. Andalusia's native sheep and goats present a great economic opportunity in a Europe where animal products are generally in strong supply, but the sheep and goat meat, milk, and leather (and the products derived from these) are relatively scarce. Dogs are bred not just as companion animals, but also as herding animals used by goat and sheep herders. + +Hunting remains relatively important in Andalusia, but has largely lost its character as a means of obtaining food. +It is now more of a leisure activity linked to the mountain areas and complementary to forestry and the raising of livestock. Dogs are frequently used as hunting companions to retrieve killed game. + +The Andalusian forests are important for their extent—50 percent of the territory of Andalusia—and for other less quantifiable environmental reasons, such as their value in preventing erosion, regulating the flow of water necessary for other flora and fauna. For these reasons, there is legislation in place to protect the Andalusian forests. The value of forest products as such constitutes only 2 percent of agricultural production. This comes mostly from cultivated species—eucalyptus in Huelva and poplar in Granada—as well as naturally occurring cork oak in the Sierra Morena. + +Fishing + +Fishing is a longstanding tradition on the Andalusian coasts. Fish and other seafood have long figured prominently in the local diet and in the local gastronomic culture: fried fish (pescaito frito in local dialect), white prawns, almadraba tuna, among others. The Andalusian fishing fleet is Spain's second largest, after Galicia, and Andalusia's 38 fishing ports are the most of any Spanish autonomous community. Commercial fishing produces only 0.5 percent of the product of the regional primary sector by value, but there are areas where it has far greater importance. In the province of Huelva it constitutes 20 percent of the primary sector, and locally in Punta Umbría 70 percent of the work force is involved in commercial fishing. + +Failure to comply with fisheries laws regarding the use of trawling, urban pollution of the seacoast, destruction of habitats by coastal construction (for example, alteration of the mouths of rivers, construction of ports), and diminution of fisheries by overexploitation +have created a permanent crisis in the Andalusian fisheries, justifying attempts to convert the fishing fleet. The decrease in fish stocks has led to the rise of aquaculture, including fish farming both on the coasts and in the interior. + +Mining + +Despite the general poor returns in recent years, mining retains a certain importance in Andalusia. Andalusia produces half of Spain's mining product by value. Of Andalusia's production, roughly half comes from the province of Huelva. Mining for precious metals at Minas de Riotinto in Huelva (see Rio Tinto Group) dates back to pre-Roman times; the mines were abandoned in the Middle Ages and rediscovered in 1556. Other mining activity is coal mining in the Guadiato valley in the province of Córdoba; various metals at Aznalcóllar in the province of Seville, and iron at Alquife in the province of Granada. In addition, limestone, clay, and other materials used in construction are well distributed throughout Andalusia. + +Secondary sector: industry +The Andalusian industrial sector has always been relatively small. Nevertheless, in 2007, Andalusian industry earned 11.979 million euros and employed more than 290,000 workers. This represented 9.15 percent of regional GDP, far below the 15.08 the secondary sector represents in the economy of Spain as a whole. By analyzing the different subsectors of the food industry Andalusian industry accounts for more than 16% of total production. In a comparison with the Spanish economy, this subsector is virtually the only food that has some weight in the national economy with 16.16%. Lies far behind the manufacturing sector of shipping materials just over 10% of the Spanish economy. Companies like Cruzcampo (Heineken Group), Puleva, Domecq, Santana Motors or Renault-Andalusia, are exponents of these two subsectors. Of note is the Andalusian aeronautical sector, which is second nationally only behind Madrid and represents approximately 21% of total turnover in terms of employment, highlighting companies like Airbus, Airbus Military, or the newly formed Aerospace Alestis. On the contrary it is symptomatic of how little weight the regional economy in such important sectors such as textiles or electronics at the national level. + +Andalusian industry is also characterized by a specialization in industrial activities of transforming raw agricultural and mineral materials. This is largely done by small enterprises without the public or foreign investment more typical of a high level of industrialization. + +Tertiary sector: services + +In recent decades the Andalusian tertiary (service) sector has grown greatly, and has come to constitute the majority of the regional economy, as is typical of contemporary economies in developed nations. In 1975 the service sector produced 51.1 percent of local GDP and employed 40.8 percent of the work force. In 2007, this had risen to 67.9 percent of GDP and 66.42 percent of jobs. This process of "tertiarization" of the economy has followed a somewhat unusual course in Andalusia. This growth occurred somewhat earlier than in most developed economies and occurred independently of the local industrial sector. There were two principal reasons that "tertiarization" followed a different course in Andalusia than elsewhere: + +1. Andalusian capital found it impossible to compete in the industrial sector against more developed regions, and was obligated to invest in sectors that were easier to enter. + +2. The absence of an industrial sector that could absorb displaced agricultural workers and artisans led to the proliferation of services with rather low productivity. This unequal development compared to other regions led to a hypertrophied and unproductive service sector, which has tended to reinforce underdevelopment, because it has not led to large accumulations of capital. + +Tourism in Andalusia + +Due in part to the relatively mild winter and spring climate, the south of Spain is attractive to overseas visitors–especially tourists from Northern Europe. While inland areas such as Jaén, Córdoba and the hill villages and towns remain relatively untouched by tourism, the coastal areas of Andalusia have heavy visitor traffic for much of the year. + +Among the autonomous communities, Andalusia is second only to Catalonia in tourism, with nearly 30 million visitors every year. The principal tourist destinations in Andalusia are the Costa del Sol and (secondarily) the Sierra Nevada. As discussed above, Andalusia is one of the sunniest and warmest places in Europe, making it a center of "sun and sand" tourism, but not only it. Around 70 percent of the lodging capacity and 75 percent of the nights booked in Andalusian hotels are in coastal municipalities. The largest number of tourists come in August—13.26 percent of the nights booked throughout the year—and the smallest number in December—5.36 percent. + +On the west (Atlantic) coast are the Costa de la Luz (provinces of Huelva and Cádiz), and on the east (Mediterranean) coast, the Costa del Sol (provinces of Cádiz y Málaga), Costa Tropical (Granada and part of Almería) and the Costa de Almería. In 2004, the Blue Flag beach program of the non-profit Foundation for Environmental Education recognized 66 Andalusian beaches and 18 pleasure craft ports as being in a good state of conservation in terms of sustainability, accessibility, and quality. Nonetheless, the level of tourism on the Andalusian coasts has been high enough to have a significant environmental impact, and other organizations—such as the Spanish Ecologists in Action (Ecologistas en Acción) with their description of "Black Flag beaches" or Greenpeace—have expressed the opposite sentiment. Still, Hotel chains such as Fuerte Hotels have ensured that sustainability within the tourism industry is one of their highest priorities. + +Together with "sand and sun" tourism, there has also been a strong increase in nature tourism in the interior, as well as cultural tourism, sport tourism, and conventions. One example of sport and nature tourism is the ski resort at Sierra Nevada National Park. + +As for cultural tourism, there are hundreds of cultural tourist destinations: cathedrals, castles, forts, monasteries, and historic city centers and a wide variety of museums. + +It can be highlighted that Spain has seven of its 42 cultural UNESCO World Heritage Sites in Andalucia: + Alhambra, Generalife and Albayzín, Granada (1984,1994) + Antequera Dolmens Site (2016) + 10th Century Caliphate City of Medina Azahara (2018) + Cathedral, Alcázar and Archivo de Indias in Seville (1987) + Historic centre of Córdoba (1984,1994) + Renaissance Monumental Ensembles of Úbeda and Baeza (2003) + Rock Art of the Mediterranean Basin on the Iberian Peninsula (1998) + +Further, there are the Lugares colombinos, significant places in the life of Christopher Columbus: Palos de la Frontera, La Rábida Monastery, and Moguer) in the province of Huelva. There are also archeological sites of great interest: the Roman city of Italica, birthplace of Emperor Trajan and (most likely) Hadrian or Baelo Claudia near Tarifa. + +Andalusia was the birthplace of such great painters as Velázquez and Murillo (Seville) and, more recently, Picasso (Málaga); Picasso is memorialized by his native city at the Museo Picasso Málaga and Natal House Foundation; the Casa de Murillo was a house museum 1982–1998, but is now mostly offices for the Andalusian Council of Culture. The CAC Málaga (Museum of Modern Art) is the most visited museum of Andalusia and has offered exhibitions of artists such as Louise Bourgeois, Jake and Dinos Chapman, Gerhard Richter, Anish Kapoor, Ron Mueck or Rodney Graham. Malaga is also located part of the private Carmen Thyssen-Bornemisza Collection at Carmen Thyssen Museum. + +There are numerous other significant museums around the region, both of paintings and of archeological artifacts such as gold jewelry, pottery and other ceramics, and other works that demonstrate the region's artisanal traditions. + +The Council of Government has designated the following "Municipios Turísticos": in Almería, Roquetas de Mar; in Cádiz, Chiclana de la Frontera, Chipiona, Conil de la Frontera, Grazalema, Rota, and Tarifa; in Granada, Almuñécar; in Huelva, Aracena; in Jaén, Cazorla; in Málaga, Benalmádena, Fuengirola, Nerja, Rincón de la Victoria, Ronda, and Torremolinos; in Seville, Santiponce. + +Monuments and features + + Alcazaba, Almería + Cueva de Menga, Antequera (Málaga) + El Torcal, Antequera (Málaga) + Medina Azahara, Córdoba + Mosque–Cathedral, Córdoba + Mudejar Quarter, Frigiliana (Málaga) + Alhambra, Granada + Palace of Charles V, Granada + Charterhouse, Granada + Albayzín, Granada + La Rabida Monastery, Palos de la Frontera (Huelva) + Castle of Santa Catalina, Jaén + Jaén Cathedral, Jaén + Úbeda and Baeza, Jaén + Alcazaba, Málaga + Buenavista Palace, Málaga + Málaga Cathedral, Málaga + Puente Nuevo, Ronda (Málaga) + Caves of Nerja, Nerja (Málaga) + Ronda Bullring, Ronda (Málaga) + Giralda, Seville + Torre del Oro, Seville + Plaza de España, Seville + Seville Cathedral, Seville + Alcázar of Seville, Seville + +Unemployment +The unemployment rate stood at 25.5% in 2017 and was one of the highest in Spain and Europe. + +Infrastructure + +Transport + +As in any modern society, transport systems are an essential structural element of the functioning of Andalusia. The transportation network facilitates territorial coordination, economic development and distribution, and intercity transportation. + +In urban transport, underdeveloped public transport systems put pedestrian traffic and other non-motorized traffic are at a disadvantage compared to the use of private vehicles. Several Andalusian capitals—Córdoba, Granada and Seville—have recently been trying to remedy this by strengthening their public transport systems and providing a better infrastructure for the use of bicycles. There are now three rapid transit systems operating in Andalucia – the Seville Metro, Málaga Metro and Granada Metro. Cercanías commuter rail networks operate in Seville, Málaga and Cádiz. + +For over a century, the conventional rail network has been centralized on the regional capital, Seville, and the national capital, Madrid; in general, there are no direct connections between provincial capitals. High-speed AVE trains run from Madrid via Córdoba to Seville and Málaga, from which a branch from Antequera to Granada opened in 2019. Further AVE routes are under construction. The Madrid-Córdoba-Seville route was the first high-velocity route in Spain (operating since 1992). Other principal routes are the one from Algeciras to Seville and from Almería via Granada to Madrid. + +Most of the principal roads have been converted into limited access highways known as autovías. The Autovía del Este (Autovía A-4) runs from Madrid through the Despeñaperros Natural Park, then via Bailén, Córdoba, and Seville to Cádiz, and is part of European route E05 in the International E-road network. The other main road in the region is the portion of European route E15, which runs as the Autovia del Mediterráneo along the Spanish Mediterranean coast. Parts of this constitute the superhighway Autopista AP-7, while in other areas it is Autovía A-7. Both of these roads run generally east–west, although the Autovía A-4 turns to the south in western Andalusia. + +Other first-order roads include the Autovía A-48 roughly along the Atlantic coast from Cádiz to Algeciras, continuing European route E05 to meet up with European route E15; the Autovía del Quinto Centenario (Autovía A-49), which continues west from Seville (where the Autovía A-4 turns toward the south) and goes on to Huelva and into Portugal as European route E01; the Autovía Ruta de la Plata (Autovía A-66), European route E803, which roughly corresponds to the ancient Roman 'Silver Route' from the mines of northern Spain, and runs north from Seville; the Autovía de Málaga (Autovía A-45), which runs south from Córdoba to Málaga; and the Autovía de Sierra Nevada (Autovía A-44), part of European route E902, which runs south from Jaén to the Mediterranean coast at Motril. + +As of 2008 Andalusia has six public airports, all of which can legally handle international flights. The Málaga Airport is dominant, handling 60.67 percent of passengers and 85 percent of its international traffic. The Seville Airport handles another 20.12 percent of traffic, and the Jerez Airport 7.17 percent, so that these three airports account for 87.96 percent of traffic. + +Málaga Airport is the international airport that offers a wide variety of international destinations. It has a daily link with twenty cities in Spain and over a hundred cities in Europe (mainly in Great Britain, Central Europe and the Nordic countries but also the main cities of Eastern Europe: Moscow, Saint Petersburg, Sofia, Riga or Bucharest), North Africa, Middle East (Riyadh, Jeddah and Kuwait) and North America (New York, Toronto and Montreal). + +The main ports are Algeciras (for freight and container traffic) and Málaga for cruise ships. Algeciras is Spain's leading commercial port, with of cargo in 2004. Seville has Spain's only commercial river port. Other significant commercial ports in Andalusia are the ports of the Bay of Cádiz, Almería and Huelva. + +The Council of Government has approved a Plan of Infrastructures for the Sustainability of Transport in Andalusia (PISTA) 2007–2013, which plans an investment of 30 billion euros during that period. + +Energy infrastructure + +The lack of high-quality fossil fuels in Andalusia has led to a strong dependency on petroleum imports. Still, Andalusia has a strong potential for the development of renewable energy, above all wind energy. The Andalusian Energy Agency established in 2005 by the autonomous government, is a new governmental organ charged with the development of energy policy and provision of a sufficient supply of energy for the community. + +The infrastructure for production of electricity consists of eight large thermal power stations, more than 70 hydroelectric power plants, two wind farms, and 14 major cogeneration facilities. Historically, the largest Andalusian business in this sector was the Compañía Sevillana de Electricidad, founded in 1894, absorbed into Endesa in 1996. +The Solar power tower PS10 was built by the Andalusian firm Abengoa in Sanlúcar la Mayor in the province of Seville, and began operating in March 2007. It is the largest existing solar power facility in Europe. Smaller solar power stations, also recent, exist at Cúllar and Galera, Granada, inaugurated by Geosol and Caja Granada. Two more large thermosolar facilities, Andasol I y II, planned at Hoya de Guadix in the province of Granada are expected to supply electricity to half a million households. The Plataforma Solar de Almería (PSA) in the Tabernas Desert is an important center for the exploration of the solar energy. + +The largest wind power firm in the region is the Sociedad Eólica de Andalucía, formed by the merger of Planta Eólica del Sur S.A. and Energía Eólica del Estrecho S.A. + +The Medgaz gas pipeline directly connects the Algerian town of Béni Saf to Almería. + +Education + +As throughout Spain, basic education in Andalusia is free and compulsory. Students are required to complete ten years of schooling, and may not leave school before the age of 16, after which students may continue on to a baccalaureate, to intermediate vocational education, to intermediate-level schooling in arts and design, to intermediate sports studies, or to the working world. + +Andalusia has a tradition of higher education dating back to the Modern Age and the University of Granada, University of Baeza, and University of Osuna. + + there were ten private or public universities in Andalusia. University studies are structured in cycles, awarding degrees based on ECTS credits in accord with the Bologna process, which the Andalusian universities are adopting in accord with the other universities of the European Higher Education Area. + +Healthcare + +Responsibility for healthcare jurisdictions devolved from the Spanish government to Andalusia with the enactment of the Statute of Autonomy. Thus, the Andalusian Health Service (Servicio Andaluz de Salud) currently manages almost all public health resources of the Community, with such exceptions as health resources for prisoners and members of the military, which remain under central administration. + +Science and technology +According to the Outreach Program for Science in Andalusia, Andalusia contributes 14 percent of Spain's scientific production behind only Madrid and Catalonia among the autonomous communities, even though regional investment in research and development (R&D) as a proportion of GDP is below the national average. The lack of research capacity in business and the low participation of the private sector in research has resulted in R&D taking place largely in the public sector. + +The Council of Innovation, Science and Business is the organ of the autonomous government responsible for universities, research, technological development, industry, and energy. The council coordinates and initiates scientific and technical innovation through specialized centers an initiatives such as the Andalusian Center for Marine Science and Technology (Centro Andaluz de Ciencia y Tecnología Marina) and Technological Corporation of Andalusia (Corporación Tecnológica de Andalucía). + +Within the private sphere, although also promoted by public administration, technology parks have been established throughout the Community, such as the Technological Park of Andalucia (Parque Tecnológico de Andalucía) in Campanillas on the outskirts of Málaga, and Cartuja 93 in Seville. Some of these parks specialize in specific sector, such as in aerospace or in food technology. The Andalusian government deployed 600,000 Ubuntu desktop computers in their schools. + +Media +Andalusia has international, national, regional, and local media organizations, which are active gathering and disseminating information (as well as creating and disseminating entertainment). + +The most notable is the public Radio y Televisión de Andalucía (RTVA), broadcasting on two regional television channels, Canal Sur and Canal Sur 2, four regional radio stations, Canal Sur Radio, Canal Fiesta Radio, Radio Andalucía Información and Canal Flamenco Radio, as well as various digital signals, most notably Canal Sur Andalucía available on cable TV throughout Spain. + +Newspapers +Different newspapers are published for each Andalusian provincial capital, comarca, or important city. Often, the same newspaper organization publishes different local editions with much shared content, with different mastheads and different local coverage. There are also popular papers distributed without charge, again typically with local editions that share much of their content. + +No single Andalusian newspaper is distributed throughout the region, not even with local editions. In eastern Andalusia the has editions tailored for the provinces of Almería, Granada, and Jaén. Grupo Joly is based in Andalucia, backed by Andalusian capital, and publishes eight daily newspapers there. Efforts to create a newspaper for the entire autonomous region have not succeeded (the most recent as of 2009 was the Diario de Andalucía). The national press (, El Mundo, ABC, etc.) include sections or editions specific to Andalusia. + +Public television + +Andalusia has two public television stations, both operated by Radio y Televisión de Andalucía (RTVA): + Canal Sur first broadcast on 28 February 1989 (Andalusia Day). + Canal Sur 2 first broadcast 5 June 1998. Programming focuses on culture, sports, and programs for children and youth. + +In addition, RTVA also operates the national and international cable channel Canal Sur Andalucía, which first broadcast in 1996 as Andalucía Televisión. + +Radio +There are four public radio stations in the region, all operated by RTVA: + , first broadcast October 1988. + , first broadcast September 1998. + , first broadcast January 2001. + , first broadcast 29 September 2008. + +Art and culture + +The patrimony of Andalusia has been shaped by its particular history and geography, as well as its complex flows of population. Andalusia has been home to a succession of peoples and civilizations, many very different from one another, each impacting the settled inhabitants. The ancient Iberians were followed by Celts, Phoenicians and other Eastern Mediterranean traders, Romans, migrating Germanic tribes, Arabs or Berbers. All have shaped the Spanish patrimony in Andalusia, which was already diffused widely in the literary and pictorial genre of the costumbrismo andaluz. + +In the 19th century, Andalusian culture came to be widely viewed as the Spanish culture par excellence, in part thanks to the perceptions of romantic travellers. In the words of Ortega y Gasset: + +Arts + +Andalusia has been the birthplace of many great artists: the classic painters Velázquez, Murillo, and Juan de Valdés Leal; the sculptors Juan Martínez Montañés, Alonso Cano and Pedro de Mena; and such modern painters as Daniel Vázquez Díaz and Pablo Picasso. + +The Spanish composer Manuel de Falla was from Cádiz and incorporated typical Andalusian melodies in his works, as did Joaquín Turina, from Seville. The great singer Camarón de la Isla was born in San Fernando, Cádiz, and Andrés Segovia who helped shape the romantic-modernist approach to classical guitar, was born in Linares, Jaén. The virtuoso Flamenco guitar player Paco de Lucia who helped internationalize Flamenco, was born in Algeciras, Cadiz. + +Architecture + +Since the Neolithic era, Andalusia has preserved important megaliths, such as the dolmens at the Cueva de Menga and the Dolmen de Viera, both at Antequera. Archeologists have found Bronze Age cities at Los Millares and El Argar. Archeological digs at Doña Blanca in El Puerto de Santa María have revealed the oldest Phoenicians city in the Iberian peninsula; major ruins have also been revealed at Roman Italica near Seville. + +Some of the greatest architecture in Andalusia was developed across several centuries and civilizations, and the region is particularly famous for its Islamic and Moorish architecture, which includes the Alhambra complex, Generalife and the Mosque-Cathedral of Córdoba. + +The traditional architecture of Andalusia retains its Roman with Arab influences brought by Muslims, with a marked Mediterranean character strongly conditioned by the climate. Traditional urban houses are constructed with shared walls to minimize exposure to high exterior temperatures. Solid exterior walls are painted with lime to minimize the heating effects of the sun. In accord with the climate and tradition of each area, the roofs may be terraces or tiled in the Roman imbrex and tegula style. One of the most characteristic elements (and one of the most obviously influenced by Roman architecture) is the interior patio or courtyard; the patios of Córdoba are particularly famous. Other characteristic elements are decorative (and functional) wrought iron gratings and the tiles known as azulejos. Landscaping—both for common private homes and homes on a more lavish scale—also carries on older traditions, with plants, flowers, and fountains, pools, and streams of water. Beyond these general elements, there are also specific local architectural styles, such as the flat roofs, roofed chimneys, and radically extended balconies of the Alpujarra, the cave dwellings of Guadix and of Granada's Sacromonte, or the traditional architecture of the Marquisate of Zenete. + +The monumental architecture of the centuries immediately after the Reconquista often displayed an assertion of Christian hegemony through architecture that referenced non-Arab influences. Some of the greatest Renaissance buildings in Andalusia are from the then-kingdom of Jaén: the Jaén Cathedral, designed in part by Andrés de Vandelvira, served as a model for the Cathedral of Malaga and Guadix; the centers of Úbeda and Baeza, dating largely from this era, are UNESCO World Heritage Sites. Seville and its kingdom also figured prominently in this era, as is shown by the Casa consistorial de Sevilla, the Hospital de las Cinco Llagas, or the Charterhouse of Jerez de la Frontera. The Palace of Charles V in Granada is uniquely important for its Italianate purism. Andalusia also has such Baroque-era buildings as the Palace of San Telmo in Seville (seat of the current autonomic presidency), the Church of Our Lady of Reposo in Campillos, and the Granada Charterhouse. Academicism gave the region the Royal Tobacco Factory in Seville and Neoclassicism the nucleus of Cádiz, such as its , Royal Prison, and the Oratorio de la Santa Cueva. + +Revivalist architecture in the 19th and 20th centuries contributed the buildings of the Ibero-American Exposition of 1929 in Seville, including the Neo-Mudéjar Plaza de España. Andalusia also preserves an important industrial patrimony related to various economic activities. + +Besides the architecture of the cities, there is also much outstanding rural architecture: houses, as well as ranch and farm buildings and dog houses. + +Sculpture + +The Iberian reliefs of Osuna, Lady of Baza, and , the Phoenician sarcophagi of Cádiz, and the Roman sculptures of the Baetic cities such as Italica give evidence of traditions of sculpture in Andalusia dating back to antiquity. There are few significant surviving sculptures from the time of al-Andalus; two notable exceptions are the lions of the Alhambra and of the Maristán of Granada (the Nasrid hospital in the Albaicín). + +The Sevillian school of sculpture dating from the 13th century onward and the Granadan school beginning toward the end of the 16th century both focused primarily on Christian religious subject matter, including many wooden altarpieces. Notable sculptors in these traditions include Lorenzo Mercadante de Bretaña, , Juan Martínez Montañés, Pedro Roldán, , Jerónimo Balbás, Alonso Cano, and Pedro de Mena. + +Non-religious sculpture has also existed in Andalusia since antiquity. A fine example from the Renaissance era is the decoration of the Casa de Pilatos in Seville. Nonetheless, non-religious sculpture played a relatively minor role until such 19th-century sculptors as . + +Painting + +As in sculpture, there were and the schools of painting. The former has figured prominently in the history of Spanish art since the 15th century and includes such important artists as Zurbarán, Velázquez and Murillo, as well as art theorists such as Francisco Pacheco. The Museum of Fine Arts of Seville and the Prado contain numerous representative works of the Sevillian school of painting. + +A specific romantic genre known as costumbrismo andaluz depicts traditional and folkloric Andalusian subjects, such as bullfighting scenes, dogs, and scenes from Andalusia's history. Important artists in this genre include Manuel Barrón, José García Ramos, Gonzalo Bilbao and Julio Romero de Torres. The genre is well represented in the private Carmen Thyssen-Bornemisza Collection, part of which is on display at Madrid's Thyssen-Bornemisza Museum and Carmen Thyssen Museum in Málaga. + +Málaga also has been and is an important artistic center. Its most illustrious representative was Pablo Picasso, one of the most influential artists of the 20th century. The city has a Museum and Natal House Foundation, dedicated to the painter. + +Literature and philosophy + +Andalusia plays a significant role in the history of Spanish-language literature, although not all of the important literature associated with Andalusia was written in Spanish. Before 1492, there was the literature written in Andalusian Arabic. Hispano-Arabic authors native to the region include Ibn Hazm, Ibn Zaydún, Ibn Tufail, Al-Mu'tamid, Ibn al-Khatib, Ibn al-Yayyab, and Ibn Zamrak or Andalusian Hebrew poets as Solomon ibn Gabirol. Ibn Quzman, of the 12th century, crafted poems in the colloquial Andalusian language. + +In 1492 Antonio de Nebrija published his celebrated Gramática de la lengua castellana ("Grammar of the Castilian language"), the first such work for a modern European language. In 1528 Francisco Delicado wrote La lozana andaluza, a novel in the orbit of La Celestina, and in 1599 the Sevillian Mateo Alemán wrote the first part of Guzmán de Alfarache, the first picaresque novel with a known author. + +The prominent humanist literary school of Seville included such writers as Juan de Mal Lara, Fernando de Herrera, Gutierre de Cetina, Luis Barahona de Soto, Juan de la Cueva, Gonzalo Argote de Molina, and Rodrigo Caro. The Córdoban Luis de Góngora was the greatest exponent of the culteranismo of Baroque poetry in the Siglo de Oro; indeed, the style is often referred to as Góngorismo. + +Literary Romanticism in Spain had one of its great centers in Andalusia, with such authors as Ángel de Saavedra, 3rd Duke of Rivas, José Cadalso and Gustavo Adolfo Bécquer. Costumbrismo andaluz existed in literature as much as in visual art, with notable examples being the Escenas andaluzas of Serafín Estébanez Calderón and the works of Pedro Antonio de Alarcón. + +Andalusian authors Ángel Ganivet, Manuel Gómez-Moreno, Manuel and Antonio Machado, and Francisco Villaespesa are all generally counted in the Generation of '98. Also of this generation were the Quintero brothers, dramatists who faithfully captured Andalusian dialects and idiosyncrasies. Also of note, 1956 Nobel Prize-winning poet Juan Ramón Jiménez was a native of Moguer, near Huelva. + +A large portion of the avant-garde Generation of '27 who gathered at the Ateneo de Sevilla on the 300th anniversary of Góngora's death were Andalusians: Federico García Lorca, Luis Cernuda, Rafael Alberti, Manuel Altolaguirre, Emilio Prados, and 1977 Nobel laureate Vicente Aleixandre. + +Certain Andalusian fictional characters have become universal archetypes: Prosper Mérimée's gypsy Carmen, P. D. Eastman's Perro, Pierre Beaumarchais's Fígaro, and Tirso de Molina's Don Juan. + +As in most regions of Spain, the principal form of popular verse is the romance, although there are also strophes specific to Andalusia, such as the soleá or the . Ballads, lullabies, street vendor's cries, nursery rhymes, and work songs are plentiful. + +Among the philosophers native to the region can be counted Seneca, Avicebron, Maimonides, Averroes, Fernán Pérez de Oliva, Sebastián Fox Morcillo, Ángel Ganivet, Francisco Giner de los Ríos and María Zambrano. + +Music of Andalusia + +The music of Andalusia includes traditional and contemporary music, folk and composed music, and ranges from flamenco to rock. Conversely, certain metric, melodic and harmonic characteristics are considered Andalusian even when written or performed by musicians from elsewhere. + +Flamenco, perhaps the most characteristically Andalusian genre of music and dance, originated in the 18th century, but is based in earlier forms from the region. The influence of the traditional music and dance of the Romani people or Gypsies is particularly clear. The genre embraces distinct vocal (cante flamenco), guitar (toque flamenco), and dance (baile flamenco) styles. + +The Andalusian Statute of Autonomy reflects the cultural importance of flamenco in its Articles 37.1.18 and 68: + +Fundamental in the history of Andalusian music are the composers Cristóbal de Morales, Francisco Guerrero, Francisco Correa de Arauxo, Manuel García, Manuel de Falla, Joaquín Turina, and , as well as one of the fathers of modern classical guitar, the guitarist Andrés Segovia. Mention should also be made of the great folk artists of the copla (music) and the cante hondo, such as Rocío Jurado, Lola Flores (La Faraona, "the pharaoh"), Juanito Valderrama and the revolutionary Camarón de la Isla. + +Prominent Andalusian rock groups include Triana and Medina Azahara. The duo Los del Río from Dos Hermanas had international success with their "Macarena", including playing at a Super Bowl half-time show in the United States, where their song has also been used as campaign music by the Democratic Party. Other notables include the singer, songwriter, and poet Joaquín Sabina, Isabel Pantoja, Rosa López, who represented Spain at Eurovision in 2002, and David Bisbal. + +On November 16, 2023, Seville will host the 24th Annual Latin Grammy Awards at the FIBES Conference and Exhibition Centre, making Seville the first city outside of the United States to host the Latin Grammy Awards. + +Film + +The portrayal of Andalusia in film is often reduced to archetypes: flamenco, bullfighting, Catholic pageantry, brigands, the property-rich and cash-poor señorito andaluz and emigrants. These images particularly predominated from the 1920s through the 1960s, and helped to consolidate a clichéd image of the region. In a very different vein, the province of Almería was the filming location for many Westerns, especially (but by no means exclusively) the Italian-directed Spaghetti Westerns. During the dictatorship of Francisco Franco, this was the extent of the film industry in Andalusia. + +Nonetheless, Andalusian film has roots as far back as José Val del Omar in the pre-Franco years, and since the Spanish transition to democracy has brought forth numerous nationally and internationally respected directors: (Heart of the Earth), Chus Gutiérrez (Poniente), (Carlos Against the World), Alberto Rodríguez (7 Virgins), Benito Zambrano (Solas), and Antonio Banderas (Summer Rain). + +Counting together feature films, documentaries, television programs, music videos etc., Andalusia has boomed from 37 projects shooting in 1999 to 1,054 in 2007, with the figure for 2007 including 19 feature films. Although feature films are the most prestigious, commercials and television are currently more economically important to the region. + +The , headquartered in Córdoba, is a government-run entity in charge of the investigation, collection and diffusion of Andalusian cinematic heritage. Other important contributors to this last activity are such annual film festivals as the Málaga Spanish Film Festival, the most important festival dedicated exclusively to cinema made in Spain, the Seville European Film Festival (SEFF), the International Festival of Short Films—Almería in Short, the Huelva Festival of Latin American Film, the Atlantic Film Show in Cádiz, the Islantilla Festival of Film and Television and the African Film Festival of Tarifa. + +Culture + +Customs and society + +Each sub-region in Andalusia has its own unique customs that represent a fusion of Catholicism and local folklore. Cities like Almería have been influenced historically by both Granada and Murcia in the use of traditional head coverings. The sombrero de Labrador, a worker's hat made of black velvet, is a signature style of the region. + +In Cádiz, traditional costumes with rural origins are worn at bullfights and at parties on the large estates. The tablao flamenco dance and the accompanying cante jondo vocal style originated in Andalusia and traditionally most often performed by the gypsy (Gitanos). One of the most distinctive cultural events in Andalusia is the Romería de El Rocío in May. It consists of a pilgrimage to the Hermitage of El Rocío in the countryside near Almonte, in honor of the Virgin of El Rocío, an image of the Virgin and Child. In recent times the Romería has attracted roughly a million pilgrims each year. + +In Jaén, the saeta is a revered form of Spanish religious song, whose form and style has evolved over many centuries. Saetas evoke strong emotion and are sung most often during public processions. Verdiales, based upon the fandango, are a flamenco music style and song form originating in Almogia, near Málaga. For this reason, the Verdiales are sometimes known as Fandangos de Málaga. The region also has a rich musical tradition of flamenco songs, or palos called cartageneras. Seville celebrates Semana Santa, one of the better known religious events within Spain. During the festival, religious fraternities dress as penitents and carry large floats of lifelike wooden sculptures representing scenes of the Passion, and images of the Virgin Mary. Sevillanas, a type of old folk music sung and written in Seville and still very popular, are performed in fairs and festivals, along with an associated dance for the music, the Baile por sevillanas. All the different regions of Andalusia have developed their own distinctive customs, but all share a connectedness to Catholicism as developed during baroque Spain society. + +Andalusian Spanish + +Andalusian Spanish is one of the most widely spoken forms of Spanish in Spain, and because of emigration patterns was very influential on American Spanish. Rather than a single dialect, it is really a range of dialects sharing some common features; among these is +the retention of more Arabic words than elsewhere in Spain, as well as some phonological differences compared with Standard Spanish. The isoglosses that mark the borders of Andalusian Spanish overlap to form a network of divergent boundaries, so there is no clear border for the linguistic region. A fringe movement promoting an Andalusian language independent from Spanish exists. + +Religion + +The territory now known as Andalusia fell within the sphere of influence of ancient Mediterranean mythological beliefs. Phoenician colonization brought the cults of Baal and Melqart; the latter lasted into Roman times as Hercules, mythical founder of both Cádiz and Seville. The Islote de Sancti Petri held the supposed tomb of Hercules, with representations of his Twelve labors; the region was the traditional site of the tenth labor, obtaining the cattle of the monster Geryon. Traditionally, the Pillars of Hercules flank the Strait of Gibraltar. Clearly, the European pillar is the Rock of Gibraltar; the African pillar was presumably either Monte Hacho in Ceuta or Jebel Musa in Morocco. The Roman road that led from Cádiz to Rome was known by several names, one of them being , Hercules route returning from his tenth labor. The present coat of arms of Andalusia shows Hercules between two lions, with two pillars behind these figures. + +Roman Catholicism is, by far, the largest religion in Andalusia. In 2012, the proportion of Andalusians that identify themselves as Roman Catholic was 78.8%. Spanish Catholic religion constitute a traditional vehicle of Andalusian cultural cohesion, and the principal characteristic of the local popular form of Catholicism is devotion to the Virgin Mary; Andalusia is sometimes known as la tierra de María Santísima ("the land of Most Holy Mary"). Also characteristic are the processions during Holy Week, in which thousands of penitents (known as nazarenos) sing saetas. Andalusia is the site of such pilgrim destinations as the in Andújar and the Hermitage of El Rocío in Almonte. + +Bullfighting + +While some trace the lineage of the Spanish Fighting Bull back to Roman times, today's fighting bulls in the Iberian peninsula and in the former Spanish Empire trace back to Andalusia in the 15th and 16th centuries. Andalusia remains a center of bull-rearing and bullfighting: its 227 fincas de ganado where fighting bulls are raised cover . In the year 2000, Andalusia's roughly 100 bullrings hosted 1,139 corridas. + +The oldest bullring still in use in Spain is the neoclassical Plaza de toros in Ronda, built in 1784. The Andalusian Autonomous Government sponsors the Rutas de Andalucía taurina, a touristic route through the region centered on bullfighting. + +Festivals + +The Andalusian festivals provide a showcase for popular arts and traditional costume. Among the most famous of these are the Seville Fair or Feria de Abril in Seville, now echoed by smaller fairs in Madrid and Barcelona, both of which have many Andalusian immigrants; the Feria de Agosto in Málaga; the Feria de Jerez or Feria del Caballo in Jerez; the in Granada; the in Córdoba; the Columbian Festivals (Fiestas Colombinas) in Huelva; the Feria de la Virgen del Mar in Almería; and the in Jaén, among many others. + +Festivals of a religious nature are a deep Andalusian tradition and are met with great popular fervor. There are numerous major festivals during Holy Week. An annual pilgrimage brings a million visitors to the Hermitage of El Rocío in Almonte (population 16,914 in 2008); similarly large crowds visit the Santuario de Nuestra Señora de la Cabeza in Andújar every April. + +Other important festivals are the Carnival of Cádiz and the Fiesta de las Cruces or Cruz de mayo in Granada and Córdoba; in Córdoba this is combined with a competition for among the patios (courtyards) of the city. + +Andalusia hosts an annual festival for the dance of flamenco in the summer-time. + +Cuisine + +The Andalusian diet varies, especially between the coast and the interior, but in general is a Mediterranean diet based on olive oil, cereals, legumes, vegetables, fish, dried fruits and nuts, and meat; there is also a great tradition of drinking wine. + +Fried fish—pescaíto frito—and seafood are common on the coast and also eaten well into the interior under coastal influence. Atlantic bluefin tuna (Thunnus thynnus) from the Almadraba areas of the Gulf of Cádiz, prawns from Sanlúcar de Barrameda (known as langostino de Sanlúcar), and deepwater rose shrimp () from Huelva are all highly prized. Fishing for the transparent goby or chanquete (Aphia minuta), a once-popular small fish from Málaga, is now banned because the techniques used to catch them trap too many immature fish of other species. + +The mountainous regions of the Sierra Morena and Sierra Nevada produce cured hams, notably including jamón serrano and jamón ibérico. These come from two different types of pig, (jamón serrano from white pigs, the more expensive jamón ibérico from the Black Iberian pig). There are several denominaciones de origen, each with its own specifications including in just which microclimate region ham of a particular denomination must be cured. Plato alpujarreño is another mountain specialty, a dish combining ham, sausage, sometimes other pork, egg, potatoes, and olive oil. + +Confectionery is popular in Andalusia. Almonds and honey are common ingredients. Many enclosed convents of nuns make and sell pastries, especially Christmas pastries: mantecados, polvorones, pestiños, alfajores, , as well as churros or , meringue cookies (merengadas), and . + +Cereal-based dishes include migas de harina in eastern Andalusia (a similar dish to couscous rather than the fried breadcrumb based migas elsewhere in Spain) and a sweeter, more aromatic porridge called poleá in western Andalusia. +Vegetables form the basis of such dishes as (similar to ratatouille) and the chopped salad known as or . Hot and cold soups based in olive oil, garlic, bread, tomato and peppers include gazpacho, salmorejo, porra antequerana, ajo caliente, sopa campera, or—using almonds instead of tomato—ajoblanco. + +Wine has a privileged place at the Andalusian table. Andalusian wines are known worldwide, especially fortified wines such as sherry (jerez), aged in soleras. These are enormously varied; for example, dry sherry may be the very distinct fino, manzanilla, amontillado, oloroso, or Palo Cortado and each of these varieties can each be sweetened with Pedro Ximénez or Moscatel to produce a different variety of sweet sherry. Besides sherry, Andalucía has five other denominaciones de origen for wine: D.O. Condado de Huelva, D.O. Manzanilla-Sanlúcar de Barrameda, D.O. Málaga, D.O. Montilla-Moriles, and D.O. Sierras de Málaga. Most Andalusian wine comes from one of these regions, but there are other historic wines without a Protected Geographical Status, for example Tintilla de Rota, Pajarete, Moscatel de Chipiona and Mosto de Umbrete. + +Andalusia also produces D.O. vinegar and brandy: D.O. Vinagre de Jerez and D.O. Brandy de Jerez. + +Other traditions + +The traditional dress of 18th-century Andalusia was strongly influenced by within the context of casticismo (purism, traditionalism, authenticity). The archetype of the majo and maja was that of a bold, pure Spaniard from a lower-class background, somewhat flamboyant in his or her style of dress. This emulation of lower-class dress also extended to imitating the clothes of brigands and Romani ("Gypsy") women. + +The Museum of Arts and Traditions of Sevilla has collected representative samples of a great deal of the history of Andalusian dress, including examples of such notable types of hat as the sombrero cordobés, sombrero calañés, sombrero de catite and the , as well as the traje corto and traje de flamenca. + +Andalusia has a great artisan tradition in tile, leather (see Shell cordovan), weaving (especially of the heavy jarapa cloth), marquetry, and ceramics (especially in Jaén, Granada, and Almería), lace (especially Granada and Huelva), embroidery (in Andévalo), ironwork, woodworking, and basketry in wicker, many of these traditions a heritage of the long period of Muslim rule. + +Andalusia is also known for its dogs, particularly the Andalusian Hound, which was originally bred in the region. Dogs, not just andalusian hounds, are very popular in the region. + +Andalusian equestrianism, institutionalized in the Royal Andalusian School of Equestrian Art is known well beyond the borders of Spain. The Andalusian horse is strongly built, compact yet elegant, distinguished in the area of dressage and show jumping, and is also an excellent horse for driving. They are known for their elegant "dancing" gait. + +Sports + +Team sports + +In Andalusia, as throughout Spain, football is the predominant sport. Introduced to Spain by British men who worked in mining for Rio Tinto in the province of Huelva, the sport soon became popular with the local population. As Spain's oldest existing football club, Recreativo de Huelva, founded 1889, is known as El Decano ("the Dean"). + +For the 2023–24 season, five Andalusian clubs compete in Spain's First Division La Liga: Cádiz CF, Real Betis, Sevilla FC, Granada CF and UD Almería. Betis won La Liga in 1934–35 and Sevilla in the 1945–46 season. The other Andalusian teams, Málaga CF play in the Segunda División, Córdoba CF play in the Primera Federación, whilst Recreativo de Huelva, participate in the Segunda Federación, and Marbella FC and Real Jaén participate in the Tercera División. + +The Andalusia autonomous football team is not in any league, and plays only friendly matches. In recent years, they have played mostly during the Christmas break of the football leagues. They play mostly against national teams from other countries, but would not be eligible for international league play, where Spain is represented by a single national team. + +In recent decades, basketball has become increasingly popular, with CB Málaga, also known as Unicaja Málaga who have won the Liga ACB in 2007 and the Korać Cup in 2001 and usually play the Euroleague, CB Sevilla (Banca Cívica) and CB Granada competing at the top level in the Liga ACB. + +Unlike basketball, handball has never really taken off in Andalusia. There is one Andalusian team in the Liga Asobal, Spain's premier handball league: BM Puente Genil, playing in the province of Córdoba. + +Andalusia's strongest showing in sports has been in table tennis. There are two professional teams: Cajasur Priego TM and Caja Granada TM, the latter being Spain's leading table tennis team, with more than 20 league championships in nearly consecutive years and 14 consecutive Copas del Rey, dominating the Liga ENEBÉ. Cajasur is also one of the league's leading teams. + +Olympics + +220 Andalusian athletes have competed in a total of 16 summer or winter Olympic Games. The first was Leopoldo Sainz de la Maza, part of the silver medal-winning polo team at the 1920 Summer Olympics in Antwerp, Belgium. + +In all, Andalusians have won six gold medals, 11 silver, and two bronze. Winners of multiple medals include the Córdoban boxer Rafael Lozano (bronze in the 1996 Summer Olympics at Atlanta, Georgia, US, and silver in the 2000 Summer Olympics in Sydney, Australia); sailor Theresa Zabell, Malagueña by adoption (gold medals at Barcelona in 1992 and Atlanta in 1996). Other notable winners have been Granadan tennis player Manuel Orantes (silver in the men's singles of the demonstration tournament in Mexico City in 1968), Jerezano riders Ignacio Rambla and Rafael Soto (silver in dressage in Athens in 2004) and the racewalker Paquillo Fernández from Guadix (silver in Athens in 2004). + +The largest number of Olympic appearances were by the Malagueña swimmer María Peláez (five appearances), the Granadan skier María José Rienda (four), the Sevillian rider Luis Astolfi (four), and the Sevillian rower Fernando Climent (four, including a silver at Los Angeles, California, US, in 1984. + +Seville has been a pre-candidate to host the Summer Olympics in two occasions, 2004 and 2008, and Granada has been a pre-candidate to host the winter Olympics; neither has ever succeeded in its candidature. The ski resort of Sierra Nevada, near Granada, has however hosted the 1996 Alpine World Ski Championships, and Granada hosted the 2015 Winter Universiade. + +Other sports +Other sporting events in Andalusia include surfing, kitesurfing and windsurfing competitions at Tarifa, various golf tournaments at courses along the coast, and horse racing and polo at several locations in the interior. Andalusia hosted the 1999 World Championships in Athletics (Seville), the 2005 Mediterranean Games (Almería) and the FIS Alpine World Ski Championships 1996 (Granada), among other major events. There is also the annual Vuelta a Andalucía bicycle road race and the Linares chess tournament. The Circuito de Jerez, located near Jerez de la Frontera, hosts the Spanish motorcycle Grand Prix. + +Twinning and covenants +Andalusia has had a sister region relationship with Buenos Aires (Argentina), since 2001; and with Córdoba (Argentina). Also Andalusia has a collaboration agreement with Guerrero (Mexico). + +See also + + Andalusian people + Andalusian nationalism + Azulejo + List of Andalusians + List of the oldest mosques + Roman Bética Route + San Juan De Los Terreros + White Towns of Andalusia + Yeseria + +References + +External links + + + Official site – Junta de Andalucia + Andalucia Tourism Site + Andalucia page at the guardian + + +Autonomous communities of Spain +NUTS 2 statistical regions of the European Union +States and territories established in 1981 +States and territories established in 2007 +Abhorrers, the name given in 1679 to the persons who expressed their abhorrence at the action of those who had signed petitions urging King Charles II of England to assemble Parliament. + +Feeling against Catholics, and especially against James, Duke of York, was running strongly; the Exclusion Bill had been passed by the House of Commons, and the popularity of James Scott, 1st Duke of Monmouth, was very great. + +To prevent this bill from passing into law, Charles had dissolved the parliament in July 1679, and in the following October had prorogued its successor, which became known as the Exclusion Bill Parliament, without allowing it to meet. He was then deluged with petitions urging him to call it together. This agitation was opposed by Sir George Jeffreys and Francis Wythens, who presented addresses expressing abhorrence of the Petitioners, and thus initiated the movement of the abhorrers, who supported the action of the king. "The frolic went all over England," says Roger North; and the addresses of the Abhorrers which reached the king from all parts of the country formed a counterblast to those of the Petitioners. It is said that the terms Whig and Tory were first applied to English political parties as consequence of this dispute. + +References + +1679 in England +Stuart England +Political history of England +Abiathar ( ʾEḇyāṯār, "father (of) abundance"/"abundant father"), in the Hebrew Bible, is a son of Ahimelech or Ahijah, High Priest at Nob, the fourth in descent from Eli and the last of Eli's House to be a High Priest. + +Bible account +Abiathar was the only one of the priests to escape from Saul's (reigned c. 1020–1000 BCE) massacre in Nob, when his father and the priests of Nob were slain on the command of Saul. He fled to David (reigned c. 1003–970 BCE) at Keilah, taking with him the ephod and other priestly regalia. Rabbinical literature that linked the later extermination of the male descendants of David with the priests of Nob, also link the survival of David's descendant Joash with that of Abiathar. + +Abiathar joined David, who was then in the cave of Adullam. He remained with David, and became priest of the party of which he was the leader. He was of great service to David, especially at the time of the rebellion of Absalom. + +When David ascended the throne of Judah, Abiathar was appointed High Priest and the "king's counselor". Meanwhile, Zadok, of the house of Eleazar, had been made High Priest. Another version says he was Co-Pontiff with Zadok during King David. These appointments continued in force until the end of David's reign. In 1 Kings 4:4, Zadok and Abiathar are found acting together as priests under Solomon. + +Abiathar was deposed (the sole historical instance of the deposition of a high priest) and banished to his home at Anathoth by Solomon, because he took part in the attempt to raise Adonijah to the throne instead of Solomon. The priesthood thus passed from the house of Ithamar to the house of Eleazar. + +In rabbinic literature +The rescue of the chief priest Abiathar, in the massacre of the priests of Nob ordered by Saul, was fortunate for the house of David; for if he had lost his life, David's descendants would through divine retaliation have been entirely wiped out of existence at the hands of Athaliah. It was David's acts that had really brought about the death of the priests, and to make amends he appointed Abiathar high priest. Abiathar retained the office until he was deserted by the Holy Spirit, without which the high priest could not successfully consult the Urim and Thummim. When David, on his flight from Absalom, recognized this loss in Abiathar, he felt compelled to put Zadok in his place. Abiathar's removal from the Priesthood fulfilled that other part of the curse on the House of Eli—that the Priesthood would pass out of the House of Eli. + +Confusion of the name +In 2 Samuel 8:17 Ahimelech, the son of Abiathar is suggested to be read, with the Syriac, for Abiathar, the son of Ahimelech. + +A similar confusion occurs in Gospel of Mark: in reporting Jesus' words, the evangelist used the name Abiathar when we might expect to see Jesus mention his father Ahimelech. Suggestions made to resolve the difficulty — e.g. that father and son each bore the same double name, or that Abiathar officiated during his father's lifetime and in his father's stead—have been supported by great names, but have not been fully accepted. + +References + +11th-century BCE High Priests of Israel +10th-century BCE High Priests of Israel +People from the Kingdom of Israel (united monarchy) +Family of Eli (biblical figure) +Abigail () was an Israelite woman in the Hebrew Bible married to Nabal; she married the future King David after Nabal's death (1 Samuel ). Abigail was David's third wife, after Ahinoam and Saul's daughter, Michal, whom Saul later married to Palti, son of Laish, when David went into hiding. + +Abigail became the mother of one of David's sons, who is listed in the Book of Chronicles under the name Daniel, in the Masoretic Text of the Books of Samuel as Chileab, and in the Septuagint text of 2 Samuel 3:3 as Δαλουια, Dalouia. Her name is spelled Abigal in in the American Standard Version. + +Name +Derived from the Hebrew word ab, "father", and the Hebrew root g-y-l, "to rejoice," the name Abigail has a variety of possible meanings including "my father's joy" and "source of joy". + +Biblical narrative +In 1 Samuel 25, Nabal demonstrates ingratitude towards David, the son of Jesse (from the tribe of Judah), and Abigail attempts to placate David, in order to stop the future King from taking revenge. She gives him food, and speaks to him, urging him not to "have on his conscience the staggering burden of needless bloodshed" (verse 31, NIV) and reminding him that God will make him a "lasting dynasty" (verse 28). Jon Levenson calls this an "undeniable adumbration" of Nathan's prophecy in 2 Samuel 7. Alice Bach notes that Abigail pronounces a "crucial prophecy," and the Talmud regards her as one of the Tanakh's seven female prophets. Levenson, however, suggests that she "senses the drift of history" from intelligence rather than from special revelation. + +After Abigail reveals to Nabal what she has done, "God struck Nabal and he died" (v. 38), after which David married her. Abigail is described as intelligent and beautiful. The Talmud amplifies this idea, mentioning her as being one of the "four women of surpassing beauty in the world" (the other three being Rahab, Sarah, and Esther). Being married to the wealthy Nabal, she is also a woman of high socioeconomic status. Whether David married her because he was attracted to her, or as an astute political move, or both is unclear. + +Abigail and David's second wife, Ahinoam the Jezreelite, accompany David and his war band as they seek refuge in Philistine territory. While David and his men are encamped near Jezreel, the women are captured by Amalekites who raided the town of Ziklag and carried off the women and children. David led the pursuit, and they were subsequently rescued. Both wives then settle with David in Hebron, where Abigail gives birth to David's second son, Chileab (also called Daniel). + +Abigail is also listed as one of the seven Jewish women prophets, the other six being Miriam, Deborah, Hannah, Sarah, Huldah, and Esther. In terms of her moral character, Abraham Kuyper argues that Abigail's conduct indicates "a most appealing character and unwavering faith," but Alice Bach regards her as subversive. + +Adele Berlin contrasts the story of Abigail with that of Bathsheba. In one, the wife prevents David from murdering her foolish and greedy husband. In the second, David orders the death of a good man because he desires his wife. "In the Abigail story, David, the potential king, is seen as increasingly strong and virtuous, whereas in the Bathsheba story, the reigning monarch shows his flaws ever more overtly and begins to lose control of his family." + +Levenson and Halpern suggest that Abigail may, in fact, also be the same person as Abigail, mother of Amasa. Richard M. Davidson, however, points out that "on the basis of the final form of Old Testament canon, references to Abigail in the biblical accounts indicate two different individuals." + +Generic use +Abigail's self-styling as a handmaid led to Abigail being a traditional term for a waiting-woman, for example as the waiting gentlewoman in Beaumont and Fletcher's The Scornful Lady, published in 1616. Jonathan Swift, Tobias Smollett, and Henry Fielding use Abigail in this generic sense, as does Charlotte Brontë. Scott, in The Abbot frequently refers to Lilias, Lady Avenel's maid as an “Abigail.” Anthony Trollope makes two references to the abigail (all lower case) in The Eustace Diamonds, at the beginning of Chapter 42, whilst Thomas Mann makes the same reference at the start of the second chapter of Part 2 in Buddenbrooks (published in 1901). William Rose Benet notes the notoriety of Abigail Hill, better known as "Mrs Masham", a lady-in-waiting to Queen Anne. George MacDonald Fraser makes mention of "an abigail fussing about the room" in his novel Flashman from The Flashman Papers series. + +In art +Abigail, and especially her meeting with David, was a common subject of European artwork in the Renaissance and post-Renaissance period. Artists depicting her, or them, include Antonio Molinari, Juan Antonio Escalante, and Peter Paul Rubens. + +Abigail is a featured figure on Judy Chicago's installation piece The Dinner Party, being represented in one of the 999 tiles of the Heritage Floor. + +Veneration +Abigail is venerated in Catholic Church as "righteous". Her feast day is 1 September. + +Citations + +General and cited references + Chicago, Judy. The Dinner Party: From Creation to Preservation. London: Merrell (2007). . + +External links + + +10th-century BC people +10th-century BC women +11th-century BC people +11th-century BC women +Christian royal saints +Christian saints from the Old Testament +Christian saints in unknown century +Eastern Orthodox royal saints +Eastern Orthodox saints +Old Testament people +Roman Catholic royal saints +Saints +Wives of David +Women in the Hebrew Bible +Abila, also spelled Abyla, may refer to: + +Places + Abila in the Decapolis, ancient city in the Levant + Abila Lysaniou, capital of ancient Abilene, northwest of present-day Damascus, Syria + Abila (Peraea), archaeological site in Jordan + Abila, Latin name of Ávila, Spain + Abyla, Roman colony in the province of Mauretania Tingitana + Mount Abila, mountain in Ceuta, autonomous city of Spain, in Africa + +Other + Abila (grasshopper), a genus of grasshoppers + +See also + Abela, a surname + Abilene (biblical) +Azad Jammu and Kashmir (; , ), abbreviated as AJK and colloquially referred to as simply Azad Kashmir, is a region administered by Pakistan as a nominally self-governing entity and constituting the western portion of the larger Kashmir region, which has been the subject of a dispute between India and Pakistan since 1947. Azad Kashmir also shares borders with the Pakistani provinces of Punjab and Khyber Pakhtunkhwa to the south and west, respectively. On its eastern side, Azad Kashmir is separated from the Indian union territory of Jammu and Kashmir (part of Indian-administered Kashmir) by the Line of Control (LoC), which serves as the de facto border between the Indian- and Pakistani-controlled parts of Kashmir. Geographically, it covers a total area of and has a total population of 4,045,366 as per the 2017 national census. + +The territory has a parliamentary form of government modelled after the British Westminster system, with the city of Muzaffarabad serving as its capital. The President of AJK is the constitutional head of state, while the Prime Minister, supported by a Council of Ministers, is the chief executive. The unicameral Azad Kashmir Legislative Assembly elects both the Prime Minister and President. The territory has its own Supreme Court and a High Court, while the Government of Pakistan's Ministry of Kashmir Affairs and Gilgit-Baltistan serves as a link between itself and Azad Jammu and Kashmir's government, although the autonomous territory is not represented in the Parliament of Pakistan. + +Northern Azad Kashmir lies in a region that experiences strong vibrations of the earth as a result of the Indian plate underthrusting the Eurasian plate. A major earthquake in 2005 killed at least 100,000 people and left another three million people displaced, causing widespread devastation to the region's infrastructure and economy. Since then, with help from the Government of Pakistan and foreign aid, reconstruction of infrastructure is underway. Azad Kashmir's economy largely depends on agriculture, services, tourism, and remittances sent by members of the British Mirpuri community. Nearly 87% of Azad Kashmiri households own farm property, and the region has the highest rate of school enrollment in Pakistan and a literacy rate of approximately 74%. + +Name +Azad Kashmir (Free Kashmir) was the title of a pamphlet issued by the Muslim Conference party at its 13th general session held in 1945 at Poonch. It is believed to have been a response to the National Conference's Naya Kashmir (New Kashmir) programme. Sources state that it was no more than a compilation of various resolutions passed by the party. But its intent seems to have been to declare that the Muslims of Jammu and Kashmir were committed to the Muslim League's struggle for a separate homeland (Pakistan), and that the Muslim Conference was the sole representative organisation of the Muslims of Kashmir. However, the following year, the party passed an "Azad Kashmir resolution" demanding that the maharaja institute a constituent assembly elected on an extended franchise. According to scholar Chitralekha Zutshi, the organisation's declared goal was to achieve responsible government under the aegis of the maharaja without association with either India or Pakistan. The following year, the party workers assembled at the house of Sardar Ibrahim on 19 July 1947 reversed the decision, demanding that the maharaja accede to Pakistan. + +Soon afterward, Sardar Ibrahim escaped to Pakistan and led the Poonch rebellion from there, with the assistance of Pakistan's prime minister Liaquat Ali Khan and other officials. Liaquat Ali Khan appointed a committee headed by Mian Iftikharuddin to draft a "declaration of freedom". On 4 October an Azad Kashmir provisional government was declared in Lahore with Ghulam Nabi Gilkar as president under the assumed name "Mr. Anwar" and Sardar Ibrahim as the prime minister. Gilkar travelled to Srinagar and was arrested by the maharaja's government. Pakistani officials subsequently appointed Sardar Ibrahim as the president of the provisional government. + +Geography + +The northern part of Azad Jammu and Kashmir encompasses the lower area of the Himalayas, including Jamgarh Peak (). However, Sarwali Peak (6326 m) in Neelum Valley is the highest peak in the state. + +The region receives rainfall in both the winter and the summer. Muzaffarabad and Pattan are among the wettest areas of Pakistan. Throughout most of the region, the average rainfall exceeds 1400 mm, with the highest average rainfall occurring near Muzaffarabad (around 1800 mm). During the summer season, monsoon floods of the rivers Jhelum and Leepa are common due to extreme rains and snow melting. + +Climate + +The southern parts of Azad Kashmir, including the Bhimber, Mirpur, and Kotli districts, have extremely hot weather in the summer and moderate cold weather in the winter. They receive rain mostly in monsoon weather. + +In the central and northern parts of the state, the weather remains moderately hot in the summer and cold and chilly in the winter. Snowfall also occurs there in December and January. + +The region receives rainfall in both the winter and the summer. Muzaffarabad and Pattan are among the wettest areas of the state, but they don't receive snow. Throughout most of the region, the average rainfall exceeds 1400 mm, with the highest average rainfall occurring near Muzaffarabad (around 1800 mm). During summer, monsoon floods of the Jhelum and Leepa rivers are common, due to high rainfall and melting snow. + +History + +At the time of the Partition of India in 1947, the British abandoned their suzerainty over the princely states, which were left with the options of joining India or Pakistan or remaining independent. Hari Singh, the maharaja of Jammu and Kashmir, wanted his state to remain independent. Muslims in the western districts of the Jammu province (current day Azad Kashmir) and in the Frontier Districts province (current day Gilgit-Baltistan) had wanted to join Pakistan. + +In Spring 1947, an uprising against the maharaja broke out in Poonch, an area bordering the Rawalpindi division of West Punjab. The maharaja's administration is said to have started levying punitive taxes on the peasantry which provoked a local revolt and the administration resorted to brutal suppression. The area's population, swelled by recently demobilised soldiers following World War II, rebelled against the maharaja's forces and gained control of almost the entire district. Following this victory, the pro-Pakistan chieftains of the western districts of Muzaffarabad, Poonch and Mirpur proclaimed a provisional Azad Jammu and Kashmir government in Rawalpindi on October 3, 1947. Ghulam Nabi Gilkar, under the assumed name "Mr. Anwar," issued a proclamation in the name of the provisional government in Muzaffarabad. However, this government quickly fizzled out with the arrest of Anwar in Srinagar. On October 24, a second provisional government of Azad Kashmir was established at Palandri under the leadership of Sardar Ibrahim Khan. + +On October 21, several thousand Pashtun tribesmen from North-West Frontier Province poured into Jammu and Kashmir to help with the rebellion against the maharaja's rule. They were led by experienced military leaders and were equipped with modern arms. The maharaja's crumbling forces were unable to withstand the onslaught. The tribesmen captured the towns of Muzaffarabad and Baramulla, the latter of which is northwest of the state capital Srinagar. On October 24, the Maharaja requested military assistance from India, which responded that it was unable to help him unless he acceded to India. Accordingly, on October 26, 1947, Maharaja Hari Singh signed an Instrument of Accession, handing over control of defence, external affairs, and communications to the Government of India in return for military aid. Indian troops were immediately airlifted into Srinagar. Pakistan intervened subsequently. Fighting ensued between the Indian and Pakistani armies, with the two areas of control more or less stabilised around what is now known as the "Line of Control". + +India later approached the United Nations, asking it to resolve the dispute, and resolutions were passed in favour of the holding of a plebiscite with regard to Kashmir's future. However, no such plebiscite has ever been held on either side, since there was a precondition that required the withdrawal of the Pakistani army along with the non-state elements and the subsequent partial withdrawal of the Indian army. from the parts of Kashmir under their respective control – a withdrawal that never took place. In 1949, a formal cease-fire line separating the Indian- and Pakistani-controlled parts of Kashmir came into effect. + +Following the 1949 cease-fire agreement with India, the government of Pakistan divided the northern and western parts of Kashmir that it controlled at the time of the cease-fire into the following two separately controlled political entities: + Azad Jammu and Kashmir (AJK) – the narrow, southern part, long, with a width varying from . + Gilgit–Baltistan formerly called the Federally Administered Northern Areas (FANA) – the much larger political entity to the north of AJK with an area of . + +In 1955, the Poonch uprising broke out. It was largely concentrated in areas of Rawalakot as well as the rest of Poonch Division. It ended in 1956. + +At one time under Pakistani control, Kashmir's Shaksgam tract, a small region along the northeastern border of Gilgit–Baltistan, was provisionally ceded by Pakistan to the People's Republic of China in 1963 and now forms part of China's Xinjiang Uygur Autonomous Region. + +In 1972, the then current border between the Indian and Pakistani controlled parts of Kashmir was designated as the "Line of Control". This line has remained unchanged since the 1972 Simla Agreement, which bound the two countries "to settle their differences by peaceful means through bilateral negotiations". Some political experts claim that, in view of that pact, the only solution to the issue is mutual negotiation between the two countries without involving a third party such as the United Nation. The 1974 Interim Constitution Act was passed by the 48-member Azad Jammu and Kashmir unicameral assembly. + +In April 1997, the Nawaz Sharif government refused to grant constitutional status to Azad Jammu and Kashmir stating that "'The grant of constitutional rights to these people will amount to unilateral annexation of these areas." + +Government + +Azad Jammu and Kashmir (AJK) is nominally a self-governing state, but ever since the 1949 ceasefire between Indian and Pakistani forces, Pakistan has exercised control over the state without incorporating it into Pakistan. Azad Kashmir has its own elected president, prime minister, legislative assembly, high court (with Azam Khan as its present chief justice), and official flag. + +Azad Kashmir's budget and tax affairs, are dealt with by the Azad Jammu and Kashmir Council rather than by Pakistan's Central Board of Revenue. The Azad Jammu and Kashmir Council is a supreme body consisting of 14 members, 8 from the government of Azad Jammu and Kashmir and 6 from the government of Pakistan. Its chairman/chief executive is the prime minister of Pakistan. Other members of the council are the president and the prime minister of Azad Kashmir (or an individual nominated by her/him) and 6 members of the AJK Legislative Assembly. Azad Kashmir Day is celebrated in Azad Jammu and Kashmir on October 24, which is the day that the Azad Jammu and Kashmir government was created in 1947. Pakistan has celebrated Kashmir Solidarity Day on February 5 of each year since 1990 as a day of protest against India's de facto sovereignty over its State of Jammu and Kashmir. That day is a national holiday in Pakistan. Pakistan observes the Kashmir Accession Day as Black Day on October 27 of each year since 1947 as a day of protest against the accession of Jammu and Kashmir State to India and its military presence in the Indian-controlled parts of Jammu and Kashmir. + +Brad Adams, the Asia director at the U.S.-based NGO Human Rights Watch said in 2006: "Although 'azad' means 'free,' the residents of Azad Kashmir are anything but; the Pakistani authorities govern the Azad Kashmir government with tight controls on basic freedoms." Scholar Christopher Snedden has observed that despite tight controls, the people of Azad Kashmir have generally accepted whatever Pakistan has done to them, which in any case has varied little from how most Pakistanis have been treated (by Pakistan). According to Christopher Snedden, one of the reasons for this was that the people of Azad Kashmir had always wanted to be part of Pakistan. + +Consequently, having little to fear from a pro-Pakistan population devoid of options, Pakistan imposed its will through the Federal Ministry of Kashmir Affairs and failed to empower the people of Azad Kashmir, allowing genuine self-government for only a short period in the 1970s. According to the interim constitution that was drawn up in the 1970s, the only political parties that are allowed to exist are those that pay allegiance to Pakistan: "No person or political party in Azad Jammu and Kashmir shall be permitted... activities prejudicial or detrimental to the State's accession to Pakistan." The pro-independence Jammu and Kashmir Liberation Front has never been allowed to contest elections in Azad Kashmir. While the interim constitution does not give them a choice, the people of Azad Kashmir have not considered any option other than joining Pakistan. Except in a legal sense, Azad Kashmir has been fully integrated into Pakistan. + +Azad Kashmir is home to a vibrant civil society. One of the organizations active in the territory and inside Pakistan is YFK-International Kashmir Lobby Group, an NGO that seeks better India-Pakistan relations through conflict resolution in Kashmir. + +Development +According to the project report by the Asian Development Bank, the bank has set out development goals for Azad Kashmir in the areas of health, education, nutrition, and social development. The whole project is estimated to cost US$76 million. Germany, between 2006 and 2014, has also donated $38 million towards the AJK Health Infrastructure Programme. + +Administrative divisions + +The state is administratively divided into three divisions which, in turn, are divided into ten districts. + +Demographics + +Population +The population of Azad Kashmir, according to the preliminary results of the 2017 Census, is 4.045 million. The website of the AJK government reports the literacy rate to be 74%, with the enrolment rate in primary school being 98% and 90% for boys and girls respectively. + +The population of Azad Kashmir is almost entirely Muslim. The people of this region culturally differ from the Kashmiris living in the Kashmir Valley of Jammu and Kashmir and are closer to the culture of Jammu. Mirpur, Kotli, and Bhimber are all old towns of the Jammu region. + +Religion +Azad Jammu and Kashmir has an almost entirely Muslim population. According to data maintained by Christian community organizations, there are around 4,500 Christian residents in the region. Bhimber is home to most of them, followed by Mirpur and Muzaffarabad. A few dozen families also live in Kotli, Poonch, and Bagh. However, the Christian community has been struggling to get residential status and property rights in AJK. There is no official data on the total number of Bahais in AJK. Only six Bahai families are known to be living in Muzaffarabad with others living in rural areas. The followers of the Ahmadi faith are estimated to be somewhere between 20,000 and 25,000, and most of them live in Kotli, Mirpur, Bhimber, and Muzaffarabad. + +Ethnic groups + +Christopher Snedden writes that most of the native residents of Azad Kashmir are not of Kashmiri ethnicity; rather, they could be called "Jammuites" due to their historical and cultural links with that region, which is coterminous with neighbouring Punjab and Hazara. Because their region was formerly a part of the princely state of Jammu and Kashmir and is named after it, many Azad Kashmiris have adopted the "Kashmiri" identity, whereas in an ethnolinguistic context, the term "Kashmiri" would ordinarily refer to natives of the Kashmir Valley region. The population of Azad Kashmir has strong historical, cultural and linguistic affinities with the neighbouring populations of upper Punjab and Potohar region of Pakistan, whereas the Sudhans have the oral tradition of the Pashtuns. + +The main communities living in this region are: +Gujjars – They are an agricultural tribe and are estimated to be the largest community living in the ten districts of Azad Kashmir. +Sudhans – (also known as Sadozai, Sardar) are the second largest tribe, living mainly in the districts of Poonch, Sudhanoti, Bagh, and Kotli in Azad Kashmir, and allegedly originating from the Pashtun areas. Together with the Rajputs, they are the source of most of Azad Kashmir's political leaders. +Jats – They are one of the larger communities of AJK and primarily inhabit the districts of Mirpur, Bhimber, and Kotli. A large Mirpuri population lives in the U.K. and it is estimated that more people of Mirpuri origins are now residing in the U.K. than in the Mirpur district, which retains strong ties with the U.K. +Rajputs – They are spread across the territory, and they number a little under half a million. Together with the Sundhans, they are the source of most of Azad Kashmir's political class. +Mughals – Largely located in the Bagh and Muzaffarabad districts. +Awans – A clan with significant numbers in Azad Jammu and Kashmir, living mainly in the Bagh, Poonch, Hattian Bala, and Muzaffarabad. Awans also reside in Punjab and Khyber Pakhtunkhwa in large numbers. +Dhund – They are a large clan in Azad Jammu and Kashmir and live mostly in the Bagh, Hattian Bala, and Muzaffarabad districts. They also inhabit Abbottabad and upper Potohar Punjab in large numbers. +Kashmiris – Ethnic Kashmiri populations are found in the Neelam Valley and the Leepa Valley (see Kashmiris in Azad Kashmir). + +Languages + +The official language of Azad Kashmir is Urdu, while English is used in higher domains. The majority of the population, however, are native speakers of other languages. The foremost among these is Pahari–Pothwari with its various dialects. There are also sizeable communities speaking Kashmiri (mostly in the north), Gujari (throughout the territory), and Dogri (in the south), as well as pockets of speakers of Kundal Shahi, Shina and Pashto. With the exception of Pashto and English, those languages belong to the Indo-Aryan language family. + +The dialects of the Pahari-Pothwari language complex cover most of the territory of Azad Kashmir. Those are also spoken across the Line of Control in the neighbouring areas of Indian Jammu and Kashmir and are closely related both to Punjabi to the south and Hinko to the northwest. The language variety in the southern districts of Azad Kashmir is known by a variety of names – including Mirpuri, Pothwari and Pahari – and is closely related to the Pothwari proper spoken to the east in the Pothohar region of Punjab. The dialects of the central districts of Azad Kashmir are occasionally referred to in the literature as Chibhali or Punchi, but the speakers themselves usually call them Pahari, an ambiguous name that is also used for several unrelated languages of the lower Himalayas. Going north, the speech forms gradually change into Hindko. Today, in the Muzaffarabad District the preferred local name for the language is Hindko, although it is still apparently more closely related to the core dialects of Pahari. Further north in the Neelam Valley the dialect, locally also known as Parmi, can more unambiguously be subsumed under Hindko. + +Another major language of Azad Kashmir is Gujari. It is spoken by several hundred thousand people among the traditionally nomadic Gujars, many of whom are nowadays settled. Not all ethnic Gujars speak Gujari, the proportion of those who have shifted to other languages is probably higher in southern Azad Kashmir. Gujari is most closely related to the Rajasthani languages (particularly Mewati), although it also shares features with Punjabi. It is dispersed over large areas in northern Pakistan and India. Within Pakistan, the Gujari dialects of Azad Kashmir are more similar, in terms of shared basic vocabulary and mutual intelligibility, to the Gujar varieties of the neighbouring Hazara region than to the dialects spoken further to the northwest in Khyber Pakhtunkhwa and north in Gilgit. + +There are scattered communities of Kashmiri speakers, notably in the Neelam Valley, where they form the second-largest language group after speakers of Hindko. There have been calls for the teaching of Kashmiri (particularly in order to counter India's claim of promoting the culture of Kashmir), but the limited attempts at introducing the language at the secondary school level have not been successful, and it is Urdu, rather than Kashmiri, that Kashmiri Muslims have seen as their identity symbol. There is an ongoing process of gradual shift to larger local languages, but at least in the Neelam Valley there still exist communities for whom Kashmiri is the sole mother tongue. + +There are speakers of Dogri in the southernmost district of Bhimber, where they are estimated to represent almost a third of the district's population. In the northernmost district of Neelam, there are small communities of speakers of several other languages. Shina, which like Kashmiri belongs to the broad Dardic group, is present in two distinct varieties spoken altogether in three villages. Pashto, of the Iranian subgroup and the majority language in the neighbouring province of Khyber Pakhtunkhwa, is spoken in two villages, both situated on the Line of Control. The endangered Kundal Shahi is native to the eponymous village and it is the only language not found outside Azad Kashmir. + +Economy + +As of 2021, GDP of Azad Jammu and Kashmir was estimated to be 10 billion pounds, giving per capita an income of £5604. Historically the economy of Azad Kashmir has been agricultural which meant that land was the main source or mean of production. This means that all food for immediate and long-term consumption was produced from the land. The produce included various crops, fruits, vegetables, etc. The land was also the source of other livelihood necessities such as wood, fuel, grazing for animals which then turned into dairy products. Because of this land was also the main source of revenue for the governments whose primary purpose for centuries was to accumulate revenue. + +Agriculture is a major part of Azad Kashmir's economy. Low-lying areas that have high populations grow crops like barley, mangoes, millet, corn (maize), and wheat, and also raise cattle. In the elevated areas that are less populated and more spread out, forestry, corn, and livestock are the main sources of income. There are mineral and marble resources in Azad Kashmir close to Mirpur and Muzaffarabad. There are also graphite deposits at Mohriwali. There are also reservoirs of low-grade coal, chalk, bauxite, and zircon. Local household industries produce carved wooden objects, textiles, and dhurrie carpets. There is also an arts and crafts industry that produces such cultural goods as namdas, shawls, pashmina, pherans, Papier-mâché, basketry copper, rugs, wood carving, silk and woolen clothing, patto, carpets, namda gubba, and silverware. Agricultural goods produced in the region include mushrooms, honey, walnuts, apples, cherries, medicinal herbs and plants, resin, deodar, kail, chir, fir, maple, and ash timber. + +The migration to the UK was accelerated and by the completion of Mangla Dam in 1967 the process of 'chain migration' became in full flow. Today, remittances from British Mirpuri community make a critical role in AJK's economy. In the mid-1950s various economic and social development processes were launched in Azad Kashmir. In the 1960s, with the construction of the Mangla Dam in Mirpur District, the Azad Jammu and Kashmir Government began to receive royalties from the Pakistani government for the electricity that the dam provided to Pakistan. During the mid-2000s, a multibillion-dollar reconstruction began in the aftermath of the 2005 Kashmir earthquake. + +In addition to agriculture, textiles, and arts and crafts, remittances have played a major role in the economy of Azad Kashmir. One analyst estimated that the figure for Azad Kashmir was 25.1% in 2001. With regard to annual household income, people living in the higher areas are more dependent on remittances than are those living in the lower areas. In the latter part of 2006, billions of dollars for development were mooted by international aid agencies for the reconstruction and rehabilitation of earthquake-hit zones in Azad Kashmir, though much of that amount was subsequently lost in bureaucratic channels, leading to considerable delays in help getting to the neediest. Hundreds of people continued to live in tents long after the earthquake. A land-use plan for the city of Muzaffarabad was prepared by the Japan International Cooperation Agency. + +Tourist destinations in the area include the following: + +Muzaffarabad, the capital city of Azad Kashmir, is located on the banks of the Jhelum and Neelum rivers. It is from Rawalpindi and Islamabad. Well-known tourist spots near Muzaffarabad are the Red Fort, Pir Chinassi, Patika, Subri Lake and Awan Patti. +The Neelam Valley is situated to the north and northeast of Muzaffarabad, The gateway to the valley. The main tourist attractions in the valley are Athmuqam, Kutton, Keran, Changan, Sharda, Kel, Arang Kel and Taobat. +Sudhanoti is one of the eight districts of Azad Kashmir in Pakistan. Sudhanoti is located away from Islamabad, the Capital of Pakistan. It is connected with Rawalpindi and Islamabad through Azad Pattan road. +Rawalakot city is the headquarters of Poonch District and is located from Islamabad. Tourist attractions in Poonch District are Banjosa Lake, Devi Gali, Tatta Pani, and Toli Pir. +Bagh city, the headquarters of Bagh District, is from Islamabad and from Muzaffarabad. The principal tourist attractions in Bagh District are Bagh Fort, Dhirkot, Sudhan Gali, Ganga Lake, Ganga Choti, Kotla Waterfall, Neela Butt, Danna, Panjal Mastan National Park, and Las Danna. +The Leepa Valley is located southeast of Muzaffarabad. It is the most charming and scenic place for tourists in Azad Kashmir. +New Mirpur City is the headquarters of Mirpur District. The main tourist attractions near New Mirpur City are the Mangla Lake and Ramkot Fort. + +Education + +The literacy rate in Azad Kashmir was 62% in 2004, higher than in any other region of Pakistan. The current literacy rate of Azad Kashmir is 76.60% in 2018. And it remained at 79.80% in 2019. According to the 2020–2021 census, the literacy rate in Azad Kashmir was 91.34%. However, only 2.2% were graduates, compared to the average of 2.9% for Pakistan. + +Universities + +The following is a list of universities recognised by Higher Education Commission of Pakistan (HEC): + +* Granted university status. + +Cadet College Pallandri + Cadet College Palandri is situated about from Islamabad + +Medical colleges +The following is a list of undergraduate medical institutions recognised by Pakistan Medical and Dental Council (PMDC) . +Mohtarma Benazir Bhutto Shaheed Medical College in Mirpur +Azad Jammu Kashmir Medical College in Muzafarabad +Poonch Medical College in Rawalakot + +Private medical colleges +Mohi-ud-Din Islamic Medical College in Mirpur + +Sports +Football, cricket, and volleyball are very popular in Azad Kashmir. Many tournaments are also held throughout the year and in the holy month of Ramazan, night-time flood-lit tournaments are also organised. + +Azad Kashmir has its own T20 tournament called the Kashmir Premier League, which started in 2021. + +New Mirpur City has a cricket stadium (Quaid-e-Azam Stadium) which has been taken over by the Pakistan Cricket Board for renovation to bring it up to the international standards. There is also a cricket stadium in Muzaffarabad with a capacity of 8,000 people. This stadium has hosted 8 matches of the Inter-District Under 19 Tournament 2013. + +There are also registered football clubs: + Pilot Football Club + Youth Football Club + Kashmir National FC + Azad Super FC + +Culture + +Tourism + +Notable people + + +Saif Ali Janjua, recipient of Nishan-e-Haider. +Aziz Khan, 11th Chairman Joint Chief of Staff Committee (CJCSC) of Pakistan Armed Forces. +Khan Muhammad Khan, politician from Poonch who served as the Chairman of the War Council during the 1947 Poonch Rebellion. +Muhammad Hayyat Khan, former President of Azad Kashmir. +Sardar Ibrahim Khan, first and longest-serving President of Azad Kashmir. +Masood Khan, former President of Azad Kashmir and current Pakistani ambassador to the United States. +Zaman Khan, cricketer currently playing for the Pakistani national cricket team. +Khalid Mahmood, British politician and Labour MP for Birmingham Perry Barr. +Mohammad Yasin, British politician and Labour MP for Bedford. + +See also + + Northern Pakistan + 1941 Census of Jammu and Kashmir + Kashmir conflict + Tourism in Azad Kashmir + List of cultural heritage sites in Azad Kashmir + Trans-Karakoram Tract + +Notes + +References + + Sources + +Further reading + +External links + + + Planning & Development Department AJ&K AJ&K Planning and Development Department + AJ&K Tourism & Archaeology Department Tourism in Azad Kashmir + + +Disputed territories in Asia +Foreign relations of Pakistan +States and territories established in 1947 +Subdivisions of Pakistan +Territorial disputes of India +2005 Kashmir earthquake +Countries and territories where Urdu is an official language +Kashmiri-speaking countries and territories +The Arabian Sea () is a region of sea in the northern Indian Ocean, bounded on the west by the Arabian Peninsula, Gulf of Aden and Guardafui Channel, on the northwest by Gulf of Oman and Iran, on the north by Pakistan, on the east by India, and on the southeast by the Laccadive Sea and the Maldives, on the southwest by Somalia. Its total area is 3,862,000 km2 (1,491,000 sq mi) and its maximum depth is 4,652 meters (15,262 ft). The Gulf of Aden in the west connects the Arabian Sea to the Red Sea through the strait of Bab-el-Mandeb, and the Gulf of Oman is in the northwest, connecting it to the Persian Gulf. + +Geography +The Arabian Sea's surface area is about . The maximum width of the sea is approximately , and its maximum depth is . The biggest river flowing into the sea is the Indus River. + +The Arabian Sea has two important branches — the Gulf of Aden in the southwest, connecting with the Red Sea through the strait of Bab-el-Mandeb; and the Gulf of Oman to the northwest, connecting with the Persian Gulf. There are also the gulfs of Khambhat and Kutch on the Indian Coast. +The Arabian Sea has been crossed by many important marine trade routes since the 3rd or 2nd millennium BCE. Major seaports include Kandla Port, Mundra Port, Pipavav Port, Dahej Port, Hazira Port, Mumbai Port, Nhava Sheva Port (Navi Mumbai), Mormugão Port (Goa), New Mangalore Port and Kochi Port in India, the Port of Karachi, Port Qasim, and the Gwadar Port in Pakistan, Chabahar Port in Iran and the Port of Salalah in Salalah, Oman. The largest islands in the Arabian Sea include Socotra (Yemen), Masirah Island (Oman), Lakshadweep (India) and Astola Island (Pakistan). +The countries with coastlines on the Arabian Sea are Yemen, Oman, Pakistan, Iran, India and the Maldives. + +Limits +The International Hydrographic Organization defines the limits of the Arabian Sea as follows: + +On the west: the eastern limit of the Gulf of Aden. +On the north: a line joining Ràs al Hadd, east point of the Arabian Peninsula (22°32'N) and Ràs Jiyùni (61°43'E) on the coast of Pakistan. +On the south: a line running from the southern extremity of Addu Atoll in the Maldives, to the eastern extremity of Ràs Hafun (the easternmost point of Africa, 10°26'N). +On the east: the western limit of the Laccadive Sea a line running from Sadashivgad on the west coast of India () to Cora Divh () and thence down the west side of the Laccadive and Maldive archipelagos to the most southerly point of Addu Atoll in the Maldives. + +Border and basin countries +Border and basin countries: + - 2,500 km coastline + - 1,050 km coastline + +Alternative names + +The Arabian Sea historically and geographically has been referred to with different names by Arabian and European geographers and travelers, including Erythraean Sea, Indian Sea, Oman sea, Erythraean, Persian Sea in para No 34-35 of the Voyage. In Indian folklore, it is referred to as Darya, Sindhu Sagar, and Arab Samudra. + +Arab geographers, sailors and nomads used to call this sea by different names, including the Akhdar (Green) Sea, Bahre Fars (Persian Sea), the Ocean Sea, the Hindu sea, the Makran Sea, the sea of Oman; among them Zakariya al-Qazwini, Al-Masudi, Ibn Hawqal and Hafiz-i Abru. They wrote: "The green sea and Indian sea and Persian sea are all one sea and in this sea there are strange creatures." in Iran and Turkey people call it Oman sea. +In the Periplus of the Erythraean Sea, as well as in some ancient maps, Erythraean Sea refers to the whole area of the northwestern Indian Ocean, including the Arabian Sea. + +Trade routes + +The Arabian Sea has been an important marine trade route since the era of the coastal sailing vessels from possibly as early as the 3rd millennium BCE, certainly the late 2nd millennium BCE through the later days known as the Age of Sail. By the time of Julius Caesar, several well-established combined land-sea trade routes depended upon water transport through the sea around the rough inland terrain features to its north. + +These routes usually began in the Far East or down river from Madhya Pradesh, India with transshipment via historic Bharuch (Bharakuccha), traversed past the inhospitable coast of modern-day Iran, then split around Hadhramaut, Yemen into two streams north into the Gulf of Aden and thence into the Levant, or south into Alexandria via Red Sea ports such as Axum. Each major route involved transhipping to pack animal caravan, travel through desert country and risk of bandits and extortionate tolls by local potentates. + +This southern coastal route past the rough country in the southern Arabian Peninsula was significant, and the Egyptian Pharaohs built several shallow canals to service the trade, one more or less along the route of today's Suez Canal, and another from the Red Sea to the Nile River, both shallow works that were swallowed up by huge sand storms in antiquity. Later the kingdom of Axum arose in Ethiopia to rule a mercantile empire rooted in the trade with Europe via Alexandria. + +Major ports +Jawaharlal Nehru Port in Mumbai is the largest port in the Arabian Sea, and the largest container port in India. +Major Indian ports in the Arabian Sea are Mundra Port, Kandla Port, Nava Sheva, Kochi Port, Mumbai Port, and Mormugão. + +The Port of Karachi, Pakistan's largest and busiest seaport lies on the coast of the sea. It is located between the Karachi towns of Kiamari and Saddar. + +The Gwadar Port of Pakistan is a warm-water, deep-sea port situated at Gwadar in Balochistan at the apex of the Arabian Sea and at the entrance of the Persian Gulf, about 460 km west of Karachi and approximately 75 km (47 mi) east of Pakistan's border with Iran. The port is located on the eastern bay of a natural hammerhead-shaped peninsula jutting out into the Arabian Sea from the coastline. + +Port of Salalah in Salalah, Oman is also a major port in the area. The International Task Force often uses the port as a base. There is a significant number of warships of all nations coming in and out of the port, which makes it a very safe bubble. The port handled just under 3.5m teu in 2009. + +Islands + +There are several islands in the Arabian Sea, with the most important ones being Lakshadweep Islands (India), Socotra (Yemen), Masirah (Oman) and Astola Island (Pakistan). + +The Lakshadweep Islands (formerly known as the Laccadive, Minicoy, and Aminidivi Islands) is a group of islands in the Laccadive Sea region of Arabian Sea, 200 to 440 km (120 to 270 mi) off the southwestern coast of India. The archipelago is a union territory and is governed by the Union Government of India. The islands form the smallest union territory of India with their total surface area being just . Next to these islands are the Maldives islands. These islands are all part of the Lakshadweep-Maldives-Chagos group of islands. + +Zalzala Koh was an island which was around for only a few years. After the 2013 earthquake in Pakistan, the mud island was formed. By 2016 the island was finished. + +Astola Island, also known as Jezira Haft Talar in Balochi, or 'Island of the Seven Hills', is a small, uninhabited island in the northern tip of the Arabian Sea in Pakistan's territorial waters. + +Socotra, also spelled Soqotra, is the largest island, being part of a small archipelago of four islands. It lies some east of the Horn of Africa and south of the Arabian Peninsula. + +Masirah and the five Khuriya Muriya Islands are islands off the southeastern coast of Oman. + +Major Cities +There are many major cities and towns in the coast of Arabian Sea. Some of the major cities are Mumbai, Muscat, Karachi, Aden, Salalah, Thiruvananthapuram, Kochi, Kozhikode, Tirur, Kollam, Mangalore, Bhavnagar, Jamnagar, Mogadishu, Gwadar, Abu Dhabi, Mundra, Dubai, Kannur, Panaji, Karwar, Udupi, Ratnagiri, Murdeshwar, Veraval , Colombo, Takamaka, and Dhiffushi. + +Oxygen minimum zone + +The Arabian Sea has one of the world's three largest oceanic oxygen minimum zones (OMZ), or “dead zones,” along with the eastern tropical North Pacific and the eastern tropical South Pacific. OMZs have very low levels of oxygen, sometimes undetectable by standard equipment. The Arabian Sea's OMZ has the lowest levels of oxygen in the world, especially in the Gulf of Oman. Causes of the OMZ may include untreated sewage as well as high temperatures on the Indian subcontinent, which increase winds blowing towards India, bringing up nutrients and reducing oxygen in the Arabian Sea's waters. In winter, phytoplankton suited to low-oxygen conditions turn the OMZ bright green. + +Environment and wildlife +The wildlife of the Arabian sea is diverse, and entirely unique because of the geographic distribution. + +Arabian Sea warming +Recent studies by Indian Institute of Tropical Meteorology confirmed that the Arabian Sea is warming monotonously; it possibly is due to by global warming. + +Native names + +Regional endonyms for the Arabian sea in languages of the coastal regions surrounding it. + +See also + Indian Ocean Rim Association + North Indian Ocean tropical cyclone + Piracy off the coast of Somalia + +References + +Sources + + A book and Atlas + +External links + + Arabian Sea (World Wildlife Fund) + + +Arabian Peninsula +Marine ecoregions +India–Pakistan border +Oman–Yemen border +Bodies of water of Pakistan +Bodies of water of Oman +Seas of Yemen +Seas of Iran +Seas of India +Bodies of water of Somalia +Bodies of water of Iran +Bodies of water of the Maldives +Seas of the Indian Ocean +Seas of Asia +Seas of Africa +Aspartame is an artificial non-saccharide sweetener 200 times sweeter than sucrose and is commonly used as a sugar substitute in foods and beverages. It is a methyl ester of the aspartic acid/phenylalanine dipeptide with brand names NutraSweet, Equal, and Canderel. Aspartame was approved by the US Food and Drug Administration (FDA) in 1974, and then again in 1981, after approval was revoked in 1980. + +Aspartame is one of the most studied food additives in the human food supply. Reviews by over 100 governmental regulatory bodies found the ingredient safe for consumption at the normal acceptable daily intake (ADI) limit. + +Uses + +Aspartame is around 180 to 200 times sweeter than sucrose (table sugar). Due to this property, even though aspartame produces of energy per gram when metabolized, about the same as sucrose, the quantity of aspartame needed to produce a sweet taste is so small that its caloric contribution is negligible. The sweetness of aspartame lasts longer than that of sucrose, so it is often blended with other artificial sweeteners such as acesulfame potassium to produce an overall taste more like that of sugar. + +Like many other peptides, aspartame may hydrolyze (break down) into its constituent amino acids under conditions of elevated temperature or high pH. This makes aspartame undesirable as a baking sweetener and prone to degradation in products hosting a high pH, as required for a long shelf life. The stability of aspartame under heating can be improved to some extent by encasing it in fats or in maltodextrin. The stability when dissolved in water depends markedly on pH. At room temperature, it is most stable at pH 4.3, where its half-life is nearly 300 days. At pH 7, however, its half-life is only a few days. Most soft-drinks have a pH between 3 and 5, where aspartame is reasonably stable. In products that may require a longer shelf life, such as syrups for fountain beverages, aspartame is sometimes blended with a more stable sweetener, such as saccharin. + +Descriptive analyses of solutions containing aspartame report a sweet aftertaste as well as bitter and off-flavor aftertastes. + +Acceptable levels of consumption + +The acceptable daily intake (ADI) value for food additives, including aspartame, is defined as the "amount of a food additive, expressed on a body weight basis, that can be ingested daily over a lifetime without appreciable health risk". The Joint FAO/WHO Expert Committee on Food Additives (JECFA) and the European Commission's Scientific Committee on Food (later becoming EFSA) have determined this value is 40 mg/kg of body weight per day for aspartame, while the FDA has set its ADI for aspartame at 50 mg/kg per day an amount equated to consuming 75 packets of commercial aspartame sweetener per day to be within a safe upper limit. + +The primary source for exposure to aspartame in the US is diet soft drinks, though it can be consumed in other products, such as pharmaceutical preparations, fruit drinks, and chewing gum among others in smaller quantities. A can of diet soda contains of aspartame, and, for a adult, it takes approximately 21 cans of diet soda daily to consume the of aspartame that would surpass the FDA's 50 mg/kg of body weight ADI of aspartame from diet soda alone. + +Reviews have analyzed studies which have looked at the consumption of aspartame in countries worldwide, including the US, countries in Europe, and Australia, among others. These reviews have found that even the high levels of intake of aspartame, studied across multiple countries and different methods of measuring aspartame consumption, are well below the ADI for safe consumption of aspartame. Reviews have also found that populations that are believed to be especially high consumers of aspartame, such as children and diabetics, are below the ADI for safe consumption, even considering extreme worst-case scenario calculations of consumption. + +In a report released on 10 December 2013, the EFSA said that, after an extensive examination of evidence, it ruled out the "potential risk of aspartame causing damage to genes and inducing cancer" and deemed the amount found in diet sodas safe to consume. + +Safety and health effects + +The safety of aspartame has been studied since its discovery, and it is a rigorously tested food ingredient. Aspartame has been deemed safe for human consumption by over 100 regulatory agencies in their respective countries, including the US Food and Drug Administration (FDA), UK Food Standards Agency, the European Food Safety Authority (EFSA), Health Canada, and Food Standards Australia New Zealand. + +Metabolism and body weight + reviews of clinical trials showed that using aspartame (or other non-nutritive sweeteners) in place of sugar reduces calorie intake and body weight in adults and children. A 2017 review of metabolic effects by consuming aspartame found that it did not affect blood glucose, insulin, total cholesterol, triglycerides, calorie intake, or body weight. While high-density lipoprotein levels were higher compared to control, they were lower compared to sucrose. + +In 2023, the World Health Organization recommended against the use of common non-saccharide sweeteners (NSS), including aspartame, to control body weight or lower the risk of non-communicable diseases, stating: "The recommendation is based on the findings of a systematic review of the available evidence which suggests that use of NSS does not confer any long-term benefit in reducing body fat in adults or children. Results of the review also suggest that there may be potential undesirable effects from long-term use of NSS, such as an increased risk of type 2 diabetes, cardiovascular diseases, and mortality in adults." + +Phenylalanine + +High levels of the naturally occurring essential amino acid phenylalanine are a health hazard to those born with phenylketonuria (PKU), a rare inherited disease that prevents phenylalanine from being properly metabolized. Because aspartame contains a small amount of phenylalanine, foods containing aspartame sold in the US must state: "Phenylketonurics: Contains Phenylalanine" on product labels. + +In the UK, foods that contain aspartame are required by the Food Standards Agency to list the substance as an ingredient, with the warning "Contains a source of phenylalanine". Manufacturers are also required to print "with sweetener(s)" on the label close to the main product name on foods that contain "sweeteners such as aspartame" or "with sugar and sweetener(s)" on "foods that contain both sugar and sweetener". + +In Canada, foods that contain aspartame are required to list aspartame among the ingredients, include the amount of aspartame per serving, and state that the product contains phenylalanine. + +Phenylalanine is one of the essential amino acids and is required for normal growth and maintenance of life. Concerns about the safety of phenylalanine from aspartame for those without phenylketonuria center largely on hypothetical changes in neurotransmitter levels as well as ratios of neurotransmitters to each other in the blood and brain that could lead to neurological symptoms. Reviews of the literature have found no consistent findings to support such concerns, and, while high doses of aspartame consumption may have some biochemical effects, these effects are not seen in toxicity studies to suggest aspartame can adversely affect neuronal function. As with methanol and aspartic acid, common foods in the typical diet, such as milk, meat, and fruits, will lead to ingestion of significantly higher amounts of phenylalanine than would be expected from aspartame consumption. + +Cancer +, regulatory agencies, including the FDA and EFSA, and the US National Cancer Institute, have concluded that consuming aspartame is safe in amounts within acceptable daily intake levels and does not cause cancer. These conclusions are based on various sources of evidence, such as reviews and epidemiological studies finding no association between aspartame and cancer. + +In July 2023, scientists for the International Agency for Research on Cancer (IARC) concluded that there was "limited evidence" for aspartame causing cancer in humans, classifying the sweetener as Group 2B (possibly carcinogenic). The lead investigator of the IARC report stated that the classification "shouldn't really be taken as a direct statement that indicates that there is a known cancer hazard from consuming aspartame. This is really more of a call to the research community to try to better clarify and understand the carcinogenic hazard that may or may not be posed by aspartame consumption." + +The Joint FAO/WHO Expert Committee on Food Additives (JECFA) added that the limited cancer assessment indicated no reason to change the recommended acceptable daily intake level of 40 mg per kg of body weight per day, reaffirming the safety of consuming aspartame within this limit. + +The FDA responded to the report by stating: + +Neurotoxicity symptoms +Reviews found no evidence that low doses of aspartame would plausibly lead to neurotoxic effects. A review of studies on children did not show any significant findings for safety concerns with regard to neuropsychiatric conditions such as panic attacks, mood changes, hallucinations, attention deficit hyperactivity disorder (ADHD), or seizures by consuming aspartame. + +Headaches +Reviews have found little evidence to indicate that aspartame induces headaches, although certain subsets of consumers may be sensitive to it. + +Water quality +Aspartame passes through wastewater treatment plants mainly unchanged. + +Mechanism of action + +The perceived sweetness of aspartame (and other sweet substances like acesulfame potassium) in humans is due to its binding of the heterodimer G protein-coupled receptor formed by the proteins TAS1R2 and TAS1R3. Aspartame is not recognized by rodents due to differences in the taste receptors. + +Metabolites + +Aspartame is rapidly hydrolyzed in the small intestine by digestive enzymes which break aspartame down into methanol, phenylalanine, aspartic acid, and further metabolites, such as formaldehyde and formic acid. Due to its rapid and complete metabolism, aspartame is not found in circulating blood, even following ingestion of high doses over 200 mg/kg. + +Aspartic acid + +Aspartic acid (aspartate) is one of the most common amino acids in the typical diet. As with methanol and phenylalanine, intake of aspartic acid from aspartame is less than would be expected from other dietary sources. At the 90th percentile of intake, aspartame provides only between 1% and 2% of the daily intake of aspartic acid. + +Methanol + +The methanol produced by aspartame metabolism is unlikely to be a safety concern for several reasons. The amount of methanol produced from aspartame-sweetened foods and beverages is likely to be less than that from food sources already in diets. With regard to formaldehyde, it is rapidly converted in the body, and the amounts of formaldehyde from the metabolism of aspartame are trivial when compared to the amounts produced routinely by the human body and from other foods and drugs. At the highest expected human doses of consumption of aspartame, there are no increased blood levels of methanol or formic acid, and ingesting aspartame at the 90th percentile of intake would produce 25 times less methanol than what would be considered toxic. + +Chemistry + +Aspartame is a methyl ester of the dipeptide of the natural amino acids L-aspartic acid and L-phenylalanine. Under strongly acidic or alkaline conditions, aspartame may generate methanol by hydrolysis. Under more severe conditions, the peptide bonds are also hydrolyzed, resulting in free amino acids. + +Two approaches to synthesis are used commercially. In the chemical synthesis, the two carboxyl groups of aspartic acid are joined into an anhydride, and the amino group is protected with a formyl group as the formamide, by treatment of aspartic acid with a mixture of formic acid and acetic anhydride. Phenylalanine is converted to its methyl ester and combined with the N-formyl aspartic anhydride; then the protecting group is removed from aspartic nitrogen by acid hydrolysis. The drawback of this technique is that a byproduct, the bitter-tasting β-form, is produced when the wrong carboxyl group from aspartic acid anhydride links to phenylalanine, with desired and undesired isomer forming in a 4:1 ratio. A process using an enzyme from Bacillus thermoproteolyticus to catalyze the condensation of the chemically altered amino acids will produce high yields without the β-form byproduct. A variant of this method, which has not been used commercially, uses unmodified aspartic acid but produces low yields. Methods for directly producing aspartyl-phenylalanine by enzymatic means, followed by chemical methylation, have also been tried but not scaled for industrial production. + +History + +Aspartame was discovered in 1965 by James M. Schlatter, a chemist working for G.D. Searle & Company. Schlatter had synthesized aspartame as an intermediate step in generating a tetrapeptide of the hormone gastrin, for use in assessing an anti-ulcer drug candidate. He discovered its sweet taste when he licked his finger, which had become contaminated with aspartame, to lift up a piece of paper. Torunn Atteraas Garin participated in the development of aspartame as an artificial sweetener. + +In 1975, prompted by issues regarding Flagyl and Aldactone, an FDA task force team reviewed 25 studies submitted by the manufacturer, including 11 on aspartame. The team reported "serious deficiencies in Searle's operations and practices". The FDA sought to authenticate 15 of the submitted studies against the supporting data. In 1979, the Center for Food Safety and Applied Nutrition (CFSAN) concluded, since many problems with the aspartame studies were minor and did not affect the conclusions, the studies could be used to assess aspartame's safety. + +In 1980, the FDA convened a Public Board of Inquiry (PBOI) consisting of independent advisors charged with examining the purported relationship between aspartame and brain cancer. The PBOI concluded aspartame does not cause brain damage, but it recommended against approving aspartame at that time, citing unanswered questions about cancer in laboratory rats. + +In 1983, the FDA approved aspartame for use in carbonated beverages and for use in other beverages, baked goods, and confections in 1993. In 1996, the FDA removed all restrictions from aspartame, allowing it to be used in all foods. As of May 2023, the FDA stated that it regards aspartame as a safe food ingredient when consumed within the acceptable daily intake level of 50 mg per kg of body weight per day. + +Several European Union countries approved aspartame in the 1980s, with EU-wide approval in 1994. The Scientific Committee on Food (SCF) reviewed subsequent safety studies and reaffirmed the approval in 2002. The European Food Safety Authority (EFSA) reported in 2006 that the previously established Acceptable daily intake (ADI) was appropriate, after reviewing yet another set of studies. + +Compendial status + British Pharmacopoeia + United States Pharmacopeia + +Commercial uses + +Under the brand names Equal, NutraSweet, and Canderel, aspartame is an ingredient in approximately 6,000 consumer foods and beverages sold worldwide, including (but not limited to) diet sodas and other soft drinks, instant breakfasts, breath mints, cereals, sugar-free chewing gum, cocoa mixes, frozen desserts, gelatin desserts, juices, laxatives, chewable vitamin supplements, milk drinks, pharmaceutical drugs and supplements, shake mixes, tabletop sweeteners, teas, instant coffees, topping mixes, wine coolers, and yogurt. It is provided as a table condiment in some countries. Aspartame is less suitable for baking than other sweeteners because it breaks down when heated and loses much of its sweetness. + +NutraSweet Company + +In 1985, Monsanto bought G.D.Searle, and the aspartame business became a separate Monsanto subsidiary, NutraSweet. In March 2000, Monsanto sold it to J.W. Childs Associates Equity Partners II L.P. European use patents on aspartame expired starting in 1987, and the US patent expired in 1992. + +Ajinomoto + +Many aspects of industrial synthesis of aspartame were established by Ajinomoto. In 2004, the market for aspartame, in which Ajinomoto, the world's largest aspartame manufacturer, had a 40% share, was a year, and consumption of the product was rising by 2% a year. Ajinomoto acquired its aspartame business in 2000 from Monsanto for $67 million (equivalent to $ in ). + +In 2007, Asda was the first British supermarket chain to remove all artificial flavourings and colours in its store brand foods. In 2008, Ajinomoto sued Asda, part of Walmart, for a malicious falsehood action concerning its aspartame product when the substance was listed as excluded from the chain's product line, along with other "nasties". In July 2009, a British court ruled in favor of Asda. In June 2010, an appeals court reversed the decision, allowing Ajinomoto to pursue a case against Asda to protect aspartame's reputation. Asda said that it would continue to use the term "no nasties" on its own-label products, but the suit was settled in 2011 with Asda choosing to remove references to aspartame from its packaging. + +In November 2009, Ajinomoto announced a new brand name for its aspartame sweetener—AminoSweet. + +Holland Sweetener Company + +A joint venture of DSM and Tosoh, the Holland Sweetener Company manufactured aspartame using the enzymatic process developed by Toyo Soda (Tosoh) and sold as the brand Sanecta. Additionally, they developed a combination aspartame-acesulfame salt under the brand name Twinsweet. They left the sweetener industry in 2006, because "global aspartame markets are facing structural oversupply, which has caused worldwide strong price erosion over the last five years", making the business "persistently unprofitable". + +Competing products + +Because sucralose, unlike aspartame, retains its sweetness after being heated, and has at least twice the shelf life of aspartame, it has become more popular as an ingredient. This, along with differences in marketing and changing consumer preferences, caused aspartame to lose market share to sucralose. In 2004, aspartame traded at about and sucralose, which is roughly three times sweeter by weight, at around . + +See also + + Alitame + Aspartame controversy + Neotame + Phenylalanine ammonia lyase + Stevia + +References + +External links + + +Amino acid derivatives +Aromatic compounds +Beta-Amino acids +Butyramides +Dipeptides +Carboxylate esters +Sugar substitutes +Methyl esters +E-number additives +AutoCAD is a 2D and +3D computer-aided design (CAD) software application for desktop, web, and mobile developed by Autodesk. It was first released in December 1982 for the CP/M and IBM PC platforms as a desktop app running on microcomputers with internal graphics controllers. Initially a DOS application, subsequent versions were later released for other platforms including Classic Mac OS (1992), Microsoft Windows (1992), web browsers (2010), iOS (2010), macOS (2010), and Android (2011). + +AutoCAD is a general drafting and design application used in industry by architects, project managers, engineers, graphic designers, city planners and other professionals to prepare technical drawings. After discontinuing the sale of perpetual licenses in January 2016, commercial versions of AutoCAD are licensed through a term-based subscription. + +History +Before AutoCAD was introduced, most commercial CAD programs ran on mainframe computers or minicomputers, with each CAD operator (user) working at a separate graphics terminal. + +Origins + +AutoCAD was derived from a program that began in 1977, and then released in 1979 called Interact CAD, also referred to in early Autodesk documents as MicroCAD, which was written prior to Autodesk's (then Marinchip Software Partners) formation by Autodesk cofounder Michael Riddle. + +The first version by Autodesk was demonstrated at the 1982 Comdex and released that December. AutoCAD supported CP/M-80 computers. As Autodesk's flagship product, by March 1986 AutoCAD had become the most ubiquitous CAD program worldwide. The 2022 release marked the 36th major release of AutoCAD for Windows and the 12th consecutive year of AutoCAD for Mac. The native file format of AutoCAD is .dwg. This and, to a lesser extent, its interchange file format DXF, have become de facto, if proprietary, standards for CAD data interoperability, particularly for 2D drawing exchange. AutoCAD has included support for .dwf, a format developed and promoted by Autodesk, for publishing CAD data. + +Features + +Compatibility with other software +ESRI ArcMap 10 permits export as AutoCAD drawing files. Civil 3D permits export as AutoCAD objects and as LandXML. Third-party file converters exist for specific formats such as Bentley MX GENIO Extension, PISTE Extension (France), ISYBAU (Germany), OKSTRA and Microdrainage (UK); also, conversion of .pdf files is feasible, however, the accuracy of the results may be unpredictable or distorted. For example, jagged edges may appear. Several vendors provide online conversions for free such as Cometdocs. + +Language +AutoCAD and AutoCAD LT are available for English, German, French, Italian, Spanish, Japanese, Korean, Chinese Simplified, Chinese Traditional, Brazilian Portuguese, Russian, Czech, Polish and Hungarian (also through additional language packs). The extent of localization varies from full translation of the product to documentation only. The AutoCAD command set is localized as a part of the software localization. + +Extensions +AutoCAD supports a number of APIs for customization and automation. These include AutoLISP, Visual LISP, VBA, .NET and ObjectARX. ObjectARX is a C++ class library, which was also the base for: + products extending AutoCAD functionality to specific fields + creating products such as AutoCAD Architecture, AutoCAD Electrical, AutoCAD Civil 3D + third-party AutoCAD-based application +There are a large number of AutoCAD plugins (add-on applications) available on the application store Autodesk Exchange Apps. +AutoCAD's DXF, drawing exchange format, allows importing and exporting drawing information. + +Vertical integration +Autodesk has also developed a few vertical programs for discipline-specific enhancements such as: + + Advance Steel + AutoCAD Architecture + AutoCAD Electrical + AutoCAD Map 3D + AutoCAD Mechanical + AutoCAD MEP + AutoCAD Plant 3D + Autodesk Civil 3D + +Since AutoCAD 2019 several verticals are included with AutoCAD subscription as Industry-Specific Toolset. + +For example, AutoCAD Architecture (formerly Architectural Desktop) permits architectural designers to draw 3D objects, such as walls, doors, and windows, with more intelligent data associated with them rather than simple objects, such as lines and circles. The data can be programmed to represent specific architectural products sold in the construction industry, or extracted into a data file for pricing, materials estimation, and other values related to the objects represented. + +Additional tools generate standard 2D drawings, such as elevations and sections, from a 3D architectural model. Similarly, Civil Design, Civil Design 3D, and Civil Design Professional support data-specific objects facilitating easy standard civil engineering calculations and representations. + +Softdesk Civil was developed as an AutoCAD add-on by a company in New Hampshire called Softdesk (originally DCA). Softdesk was acquired by Autodesk, and Civil became Land Development Desktop (LDD), later renamed Land Desktop. Civil 3D was later developed and Land Desktop was retired. + +File formats +AutoCAD's native file formats are denoted either by a .dwg, .dwt, .dws, or .dxf filename extension. + +The primary file format for 2D and 3D drawing files created with AutoCAD is .dwg. While other third-party CAD software applications can create .dwg files, AutoCAD uniquely creates RealDWG files. + +Using AutoCAD, any .dwg file may be saved to a derivative format. These derivative formats include: + Drawing Template Files .dwt: New .dwg are created from a .dwt file. Although the default template file is acad.dwt for AutoCAD and acadlt.dwt for AutoCAD LT, custom .dwt files may be created to include foundational configurations such as drawing units and layers. + Drawing Standards File .dws: Using the CAD Standards feature of AutoCAD, a Drawing Standards File may be associated to any .dwg or .dwt file to enforce graphical standards. + Drawing Interchange Format .dxf: The .dxf format is an ASCII representation of a .dwg file, and is used to transfer data between various applications. + +Variants + +AutoCAD LT +AutoCAD LT is the lower-cost version of AutoCAD, with reduced capabilities, first released in November 1993. Autodesk developed AutoCAD LT to have an entry-level CAD package to compete in the lower price level. Priced at $495, it became the first AutoCAD product priced below $1000. It was sold directly by Autodesk and in computer stores unlike the full version of AutoCAD, which must be purchased from official Autodesk dealers. AutoCAD LT 2015 introduced Desktop Subscription service from $360 per year; as of 2018, three subscription plans were available, from $50 a month to a 3-year, $1170 license. + +While there are hundreds of small differences between the full AutoCAD package and AutoCAD LT, there are a few recognized major differences in the software's features: + + 3D capabilities: AutoCAD LT lacks the ability to create, visualize and render 3D models as well as 3D printing. + Network licensing: AutoCAD LT cannot be used on multiple machines over a network. + Customization: AutoCAD LT does not support customization with LISP, ARX, .NET and VBA. + Management and automation capabilities with Sheet Set Manager and Action Recorder. + CAD standards management tools. + +AutoCAD Mobile and AutoCAD Web +AutoCAD Mobile and AutoCAD Web (formerly AutoCAD WS and AutoCAD 360) is an account-based mobile and web application enabling registered users to view, edit, and share AutoCAD files via mobile device and web using a limited AutoCAD feature set — and using cloud-stored drawing files. The program, which is an evolution and combination of previous products, uses a freemium business model with a free plan and two paid levels, including various amounts of storage, tools, and online access to drawings. 360 includes new features such as a "Smart Pen" mode and linking to third-party cloud-based storage such as Dropbox. Having evolved from Flash-based software, AutoCAD Web uses HTML5 browser technology available in newer browsers including Firefox and Google Chrome. + +AutoCAD WS began with a version for the iPhone and subsequently expanded to include versions for the iPod Touch, iPad, Android phones, and Android tablets. Autodesk released the iOS version in September 2010, following with the Android version on April 20, 2011. The program is available via download at no cost from the App Store (iOS), Google Play (Android) and Amazon Appstore (Android). + +In its initial iOS version, AutoCAD WS supported drawing of lines, circles, and other shapes; creation of text and comment boxes; and management of color, layer, and measurements — in both landscape and portrait modes. Version 1.3, released August 17, 2011, added support for unit typing, layer visibility, area measurement and file management. The Android variant includes the iOS feature set along with such unique features as the ability to insert text or captions by voice command as well as manually. Both Android and iOS versions allow the user to save files on-line — or off-line in the absence of an Internet connection. + +In 2011, Autodesk announced plans to migrate the majority of its software to "the cloud", starting with the AutoCAD WS mobile application. + +According to a 2013 interview with Ilai Rotbaein, an AutoCAD WS product manager for Autodesk, the name AutoCAD WS had no definitive meaning, and was interpreted variously as Autodesk Web Service, White Sheet or Work Space. In 2013, AutoCAD WS was renamed to AutoCAD 360. Later, it was renamed to AutoCAD Web App. + +Student versions +AutoCAD is licensed, for free, to students, educators, and educational institutions, with a 12-month renewable license available. Licenses acquired before March 25, 2020 were a 36-month license, with its last renovation on March 24, 2020. The student version of AutoCAD is functionally identical to the full commercial version, with one exception: DWG files created or edited by a student version have an internal bit-flag set (the "educational flag"). When such a DWG file is printed by any version of AutoCAD (commercial or student) older than AutoCAD 2014 SP1 or AutoCAD 2019 and newer, the output includes a plot stamp/banner on all four sides. Objects created in the Student Version cannot be used for commercial use. Student Version objects "infect" a commercial version DWG file if they are imported in versions older than AutoCAD 2015 or newer than AutoCAD 2018. + +Ports + +Windows + +AutoCAD Release 12 in 1992 was the first version of the software to support the Windows platform - in that case Windows 3.1. After Release 14 in 1997, support for MS-DOS, Unix and Macintosh were dropped, and AutoCAD was exclusively Windows supported. In general any new AutoCAD version supports the current Windows version and some older ones. AutoCAD 2016 to 2020 support Windows 7 up to Windows 10. + +Mac +Autodesk stopped supporting Apple's Macintosh computers in 1994. Over the next several years, no compatible versions for the Mac were released. In 2010 Autodesk announced that it would once again support Apple's Mac OS X software in the future. Most of the features found in the 2012 Windows version can be found in the 2012 Mac version. The main difference is the user interface and layout of the program. The interface is designed so that users who are already familiar with Apple's macOS software will find it similar to other Mac applications. Autodesk has also built-in various features in order to take full advantage of Apple's Trackpad capabilities as well as the full-screen mode in Apple's OS X Lion. AutoCAD 2012 for Mac supports both the editing and saving of files in DWG formatting that will allow the file to be compatible with other platforms besides macOS. AutoCAD 2019 for Mac requires OS X El Capitan or later. + +AutoCAD LT 2013 was available through the Mac App Store for $899.99. The full-featured version of AutoCAD 2013 for Mac, however, wasn't available through the Mac App Store due to the price limit of $999 set by Apple. AutoCAD 2014 for Mac was available for purchase from Autodesk's web site for $4,195 and AutoCAD LT 2014 for Mac for $1,200, or from an Autodesk authorized reseller. The latest version available for Mac is AutoCAD 2022 as of January 2022. + +Version history + +See also + Autodesk 3ds Max + Autodesk Maya + Autodesk Revit + AutoShade + AutoSketch + Comparison of computer-aided design software + Design Web Format +Open source CAD software: + LibreCAD + FreeCAD + BRL-CAD + +References + +Further reading + +External links + + + Engineering and Design Firm + +Autodesk products + +1982 software +IRIX software +Computer-aided design software +IOS software +Classic Mac OS software +Android (operating system) software +MacOS computer-aided design software +Software that uses Qt +AutoCAD DXF (Drawing Interchange Format, or Drawing Exchange Format) is a CAD data file format developed by Autodesk for enabling data interoperability between AutoCAD and other programs. + +DXF was introduced in December 1982 as part of AutoCAD 1.0, and was intended to provide an exact representation of the data in the AutoCAD native file format, DWG (Drawing). For many years, Autodesk did not publish specifications, making correct creation of DXF files difficult. Autodesk now publishes the incomplete DXF specifications online. + +Versions of AutoCAD from Release 10 (October 1988) and up support both ASCII and binary forms of DXF. Earlier versions support only ASCII. + +As AutoCAD has become more powerful, supporting more complex object types, DXF has become less useful. Certain object types, including ACIS solids and regions, are not documented. Other object types, including AutoCAD 2006's dynamic blocks, and all of the objects specific to the vertical market versions of AutoCAD, are partially documented, but not well enough to allow other developers to support them. For these reasons many CAD applications use the DWG format which can be licensed from Autodesk or non-natively from the Open Design Alliance. DXF files do not specify the units of measurement used for its coordinates and dimensions. + +Most CAD systems and many vector graphics packages support the import and export of DXF files, notably Adobe products, Inkscape & Blender. Some CAD systems use DXF as their native format, notably QCAD and LibreCAD. + +File structure +ASCII versions of DXF can be read with any text editor. The basic organization of a DXF file is as follows: + section + General information about the drawing. Each parameter has a variable name and an associated value. + section + Holds the information for application-defined classes whose instances appear in the , , and sections of the database. Generally does not provide sufficient information to allow interoperability with other programs. + section + This section contains definitions of named items. + Application ID () table + Block Record () table + Dimension Style () table + Layer () table + Linetype () table + Text style () table + User Coordinate System () table + View () table + Viewport configuration () table + + section + This section contains Block Definition entities describing the entities comprising each Block in the drawing. + section + This section contains the drawing entities, including any Block References. + section + Contains the data that apply to nongraphical objects, used by AutoLISP, and ObjectARX applications. + section + Contains the preview image for the DXF file. + + +The data format of a DXF is called a "tagged data" format, which "means that each data element in the file is preceded by an integer number that is called a group code. A group code's value indicates what type of data element follows. This value also indicates the meaning of a data element for a given object (or record) type. Virtually all user-specified information in a drawing file can be represented in DXF format." + +Criticism +Because DXF is only partially and poorly documented, missing documentation of key functionality like blocks & layouts, consideration is often given to alternative open formats like SVG (an open format defined by the W3C), DWF (an open format defined by Autodesk) or even EPS (ISO/IEC standard 29112:2018). DXF (as well as DWG) is however still a prefered format for CAD files for use by the ISO. + +See also + Design Web Format (DWF) + Open Design Alliance (originally called OpenDWG) + +References + +External links + + AutoCAD DXF Reference (from Release 14, 1998) (PDF version from 2012) + AutoCAD DXF File Format Summary. + Annotated example DXF file + AutoDesk Online DXF File Viewer. + +1982 introductions +DXF +Autodesk products +DXF +Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the full set of genes of their single parent and thus the newly created individual is genetically and physically similar to the parent or an exact clone of the parent. Asexual reproduction is the primary form of reproduction for single-celled organisms such as archaea and bacteria. Many eukaryotic organisms including plants, animals, and fungi can also reproduce asexually. In vertebrates, the most common form of asexual reproduction is parthenogenesis, which is typically used as an alternative to sexual reproduction in times when reproductive opportunities are limited. Komodo dragons and some monitor lizards can reproduce asexually. + +While all prokaryotes reproduce without the formation and fusion of gametes, mechanisms for lateral gene transfer such as conjugation, transformation and transduction can be likened to sexual reproduction in the sense of genetic recombination in meiosis. + +Types of asexual reproduction + +Fission + +Prokaryotes (Archaea and Bacteria) reproduce asexually through binary fission, in which the parent organism divides in two to produce two genetically identical daughter organisms. Eukaryotes (such as protists and unicellular fungi) may reproduce in a functionally similar manner by mitosis; most of these are also capable of sexual reproduction. + +Multiple fission at the cellular level occurs in many protists, e.g. sporozoans and algae. The nucleus of the parent cell divides several times by mitosis, producing several nuclei. The cytoplasm then separates, creating multiple daughter cells. + +In apicomplexans, multiple fission, or schizogony appears either as merogony, sporogony or gametogony. Merogony results in merozoites, which are multiple daughter cells, that originate within the same cell membrane, sporogony results in sporozoites, and gametogony results in microgametes. + +Budding + +Some cells divide by budding (for example baker's yeast), resulting in a "mother" and a "daughter" cell that is initially smaller than the parent. Budding is also known on a multicellular level; an animal example is the hydra, which reproduces by budding. The buds grow into fully matured individuals which eventually break away from the parent organism. + +Internal budding is a process of asexual reproduction, favoured by parasites such as Toxoplasma gondii. It involves an unusual process in which two (endodyogeny) or more (endopolygeny) daughter cells are produced inside a mother cell, which is then consumed by the offspring prior to their separation. + +Also, budding (external or internal) occurs in some worms like Taenia or Echinococcus; these worms produce cysts and then produce (invaginated or evaginated) protoscolex with budding. + +Vegetative propagation + +Vegetative propagation is a type of asexual reproduction found in plants where new individuals are formed without the production of seeds or spores and thus without syngamy or meiosis. Examples of vegetative reproduction include the formation of miniaturized plants called plantlets on specialized leaves, for example in kalanchoe (Bryophyllum daigremontianum) and many produce new plants from rhizomes or stolon (for example in strawberry). Some plants reproduce by forming bulbs or tubers, for example tulip bulbs and Dahlia tubers. In these examples, all the individuals are clones, and the clonal population may cover a large area. + +Spore formation + +Many multicellular organisms produce spores during their biological life cycle in a process called sporogenesis. Exceptions are animals and some protists, which undergo meiosis immediately followed by fertilization. Plants and many algae on the other hand undergo sporic meiosis where meiosis leads to the formation of haploid spores rather than gametes. These spores grow into multicellular individuals called gametophytes, without a fertilization event. These haploid individuals produce gametes through mitosis. Meiosis and gamete formation therefore occur in separate multicellular generations or "phases" of the life cycle, referred to as alternation of generations. Since sexual reproduction is often more narrowly defined as the fusion of gametes (fertilization), spore formation in plant sporophytes and algae might be considered a form of asexual reproduction (agamogenesis) despite being the result of meiosis and undergoing a reduction in ploidy. However, both events (spore formation and fertilization) are necessary to complete sexual reproduction in the plant life cycle. + +Fungi and some algae can also utilize true asexual spore formation, which involves mitosis giving rise to reproductive cells called mitospores that develop into a new organism after dispersal. This method of reproduction is found for example in conidial fungi and the red algae Polysiphonia, and involves sporogenesis without meiosis. Thus the chromosome number of the spore cell is the same as that of the parent producing the spores. However, mitotic sporogenesis is an exception and most spores, such as those of plants and many algae, are produced by meiosis. + +Fragmentation + +Fragmentation is a form of asexual reproduction where a new organism grows from a fragment of the parent. Each fragment develops into a mature, fully grown individual. Fragmentation is seen in many organisms. Animals that reproduce asexually include planarians, many annelid worms including polychaetes and some oligochaetes, turbellarians and sea stars. Many fungi and plants reproduce asexually. Some plants have specialized structures for reproduction via fragmentation, such as gemmae in mosses and liverworts. Most lichens, which are a symbiotic union of a fungus and photosynthetic algae or cyanobacteria, reproduce through fragmentation to ensure that new individuals contain both symbionts. These fragments can take the form of soredia, dust-like particles consisting of fungal hyphae wrapped around photobiont cells. + +Clonal Fragmentation in multicellular or colonial organisms is a form of asexual reproduction or cloning where an organism is split into fragments. Each of these fragments develop into mature, fully grown individuals that are clones of the original organism. In echinoderms, this method of reproduction is usually known as fissiparity. Due to many environmental and epigenetic differences, clones originating from the same ancestor might actually be genetically and epigenetically different. + +Agamogenesis +Agamogenesis is any form of reproduction that does not involve a male gamete. Examples are parthenogenesis and apomixis. + +Parthenogenesis + +Parthenogenesis is a form of agamogenesis in which an unfertilized egg develops into a new individual. It has been documented in over 2,000 species. Parthenogenesis occurs in the wild in many invertebrates (e.g. water fleas, rotifers, aphids, stick insects, some ants, bees and parasitic wasps) and vertebrates (mostly reptiles, amphibians, and fish). It has also been documented in domestic birds and in genetically altered lab mice. Plants can engage in parthenogenesis as well through a process called apomixis. However this process is considered by many to not be an independent reproduction method, but instead a breakdown of the mechanisms behind sexual reproduction. Parthenogenetic organisms can be split into two main categories: facultative and obligate. + +Facultative parthenogenesis + +In facultative parthenogenesis, females can reproduce both sexually and asexually. Because of the many advantages of sexual reproduction, most facultative parthenotes only reproduce asexually when forced to. This typically occurs in instances when finding a mate becomes difficult. For example, female zebra sharks will reproduce asexually if they are unable to find a mate in their ocean habitats. + +Parthenogenesis was previously believed to rarely occur in vertebrates, and only be possible in very small animals. However, it has been discovered in many more species in recent years. Today, the largest species that has been documented reproducing parthenogenically is the Komodo dragon at 10 feet long and over 300 pounds. + +Heterogony is a form of facultative parthenogenesis where females alternate between sexual and asexual reproduction at regular intervals (see Alternation between sexual and asexual reproduction). Aphids are one group of organism that engages in this type of reproduction. They use asexual reproduction to reproduce quickly and create winged offspring that can colonize new plants and reproduce sexually in the fall to lay eggs for the next season. However, some aphid species are obligate parthenotes. + +Obligate parthenogenesis + +In obligate parthenogenesis, females only reproduce asexually. One example of this is the desert grassland whiptail lizard, a hybrid of two other species. Typically hybrids are infertile but through parthenogenesis this species has been able to develop stable populations. + +Gynogenesis is a form of obligate parthenogenesis where a sperm cell is used to initiate reproduction. However, the sperm's genes never get incorporated into the egg cell. The best known example of this is the Amazon molly. Because they are obligate parthenotes, there are no males in their species so they depend on males from a closely related species (the Sailfin molly) for sperm. + +Apomixis and nucellar embryony + +Apomixis in plants is the formation of a new sporophyte without fertilization. It is important in ferns and in flowering plants, but is very rare in other seed plants. In flowering plants, the term "apomixis" is now most often used for agamospermy, the formation of seeds without fertilization, but was once used to include vegetative reproduction. An example of an apomictic plant would be the triploid European dandelion. Apomixis mainly occurs in two forms: In gametophytic apomixis, the embryo arises from an unfertilized egg within a diploid embryo sac that was formed without completing meiosis. In nucellar embryony, the embryo is formed from the diploid nucellus tissue surrounding the embryo sac. Nucellar embryony occurs in some citrus seeds. Male apomixis can occur in rare cases, such as in the Saharan Cypress Cupressus dupreziana, where the genetic material of the embryo is derived entirely from pollen. + +Alternation between sexual and asexual reproduction + +Some species can alternate between sexual and asexual strategies, an ability known as heterogamy, depending on many conditions. Alternation is observed in several rotifer species (cyclical parthenogenesis e.g. in Brachionus species) and a few types of insects. + +One example of this is aphids which can engage in heterogony. In this system, females are born pregnant and produce only female offspring. This cycle allows them to reproduce very quickly. However, most species reproduce sexually once a year. This switch is triggered by environmental changes in the fall and causes females to develop eggs instead of embryos. This dynamic reproductive cycle allows them to produce specialized offspring with polyphenism, a type of polymorphism where different phenotypes have evolved to carry out specific tasks. + +The cape bee Apis mellifera subsp. capensis can reproduce asexually through a process called thelytoky. The freshwater crustacean Daphnia reproduces by parthenogenesis in the spring to rapidly populate ponds, then switches to sexual reproduction as the intensity of competition and predation increases. Monogonont rotifers of the genus Brachionus reproduce via cyclical parthenogenesis: at low population densities females produce asexually and at higher densities a chemical cue accumulates and induces the transition to sexual reproduction. Many protists and fungi alternate between sexual and asexual reproduction. A few species of amphibians, reptiles, and birds have a similar ability. + +The slime mold Dictyostelium undergoes binary fission (mitosis) as single-celled amoebae under favorable conditions. However, when conditions turn unfavorable, the cells aggregate and follow one of two different developmental pathways, depending on conditions. In the social pathway, they form a multi-cellular slug which then forms a fruiting body with asexually generated spores. In the sexual pathway, two cells fuse to form a giant cell that develops into a large cyst. When this macrocyst germinates, it releases hundreds of amoebic cells that are the product of meiotic recombination between the original two cells. + +The hyphae of the common mold (Rhizopus) are capable of producing both mitotic as well as meiotic spores. Many algae similarly switch between sexual and asexual reproduction. A number of plants use both sexual and asexual means to produce new plants, some species alter their primary modes of reproduction from sexual to asexual under varying environmental conditions. + +Inheritance in asexual species +In the rotifer Brachionus calyciflorus asexual reproduction (obligate parthenogenesis) can be inherited by a recessive allele, which leads to loss of sexual reproduction in homozygous offspring. +Inheritance of asexual reproduction by a single recessive locus has also been found in the parasitoid wasp Lysiphlebus fabarum. + +Examples in animals + +Asexual reproduction is found in nearly half of the animal phyla. Parthenogenesis occurs in the hammerhead shark and the blacktip shark. In both cases, the sharks had reached sexual maturity in captivity in the absence of males, and in both cases the offspring were shown to be genetically identical to the mothers. The New Mexico whiptail is another example. + +Some reptiles use the ZW sex-determination system, which produces either males (with ZZ sex chromosomes) or females (with ZW or WW sex chromosomes). Until 2010, it was thought that the ZW chromosome system used by reptiles was incapable of producing viable WW offspring, but a (ZW) female boa constrictor was discovered to have produced viable female offspring with WW chromosomes. The female boa could have chosen any number of male partners (and had successfully in the past) but on this occasion she reproduced asexually, creating 22 female babies with WW sex-chromosomes. + +Polyembryony is a widespread form of asexual reproduction in animals, whereby the fertilized egg or a later stage of embryonic development splits to form genetically identical clones. Within animals, this phenomenon has been best studied in the parasitic Hymenoptera. In the nine-banded armadillos, this process is obligatory and usually gives rise to genetically identical quadruplets. In other mammals, monozygotic twinning has no apparent genetic basis, though its occurrence is common. There are at least 10 million identical human twins and triplets in the world today. + +Bdelloid rotifers reproduce exclusively asexually, and all individuals in the class Bdelloidea are females. Asexuality evolved in these animals millions of years ago and has persisted since. There is evidence to suggest that asexual reproduction has allowed the animals to evolve new proteins through the Meselson effect that have allowed them to survive better in periods of dehydration. Bdelloid rotifers are extraordinarily resistant to damage from ionizing radiation due to the same DNA-preserving adaptations used to survive dormancy. These adaptations include an extremely efficient mechanism for repairing DNA double-strand breaks. This repair mechanism was studied in two Bdelloidea species, Adineta vaga, and Philodina roseola. and appears to involve mitotic recombination between homologous DNA regions within each species. + +Molecular evidence strongly suggests that several species of the stick insect genus Timema have used only asexual (parthenogenetic) reproduction for millions of years, the longest period known for any insect. Similar findings suggest that the mite species Oppiella nova may have reproduced entirely asexually for millions of years. + +In the grass thrips genus Aptinothrips there have been several transitions to asexuality, likely due to different causes. + +Adaptive significance of asexual reproduction +A complete lack of sexual reproduction is relatively rare among multicellular organisms, particularly animals. It is not entirely understood why the ability to reproduce sexually is so common among them. Current hypotheses suggest that asexual reproduction may have short term benefits when rapid population growth is important or in stable environments, while sexual reproduction offers a net advantage by allowing more rapid generation of genetic diversity, allowing adaptation to changing environments. Developmental constraints may underlie why few animals have relinquished sexual reproduction completely in their life-cycles. Almost all asexual modes of reproduction maintain meiosis either in a modified form or as an alternative pathway. Facultatively apomictic plants increase frequencies of sexuality relative to apomixis after abiotic stress. Another constraint on switching from sexual to asexual reproduction would be the concomitant loss of meiosis and the protective recombinational repair of DNA damage afforded as one function of meiosis. + +See also + + Alternation of generations + Self-fertilization + Bacterial conjugation + Biological life cycle + Biological reproduction, also simply reproduction + Cloning + Hermaphrodite + Plant reproduction + Sex + +References + +Further reading + +External links + + Asexual reproduction + Intestinal Protozoa +Aelbert Jacobszoon Cuyp or Cuijp (; 20 October 1620 – 15 November 1691) was one of the leading Dutch Golden Age painters, producing mainly landscapes. The most famous of a family of painters, the pupil of his father, Jacob Gerritszoon Cuyp (1594–1651/52), he is especially known for his large views of Dutch riverside scenes in a golden early morning or late afternoon light. He was born and died in Dordrecht. + +Biography +Known as the Dutch equivalent of Claude Lorrain, he inherited a considerable fortune. His family were all artists, with his uncle Benjamin and grandfather Gerrit being stained glass cartoon designers. Jacob Gerritszoon Cuyp, his father, was a portraitist. Cuyp's father was his first teacher and they collaborated on many paintings throughout his lifetime. +Little is known about Aelbert Cuyp's life. Even Arnold Houbraken, a noted historian of Dutch Golden Age paintings and the sole authority on Cuyp for the hundred years following his death, paints a very thin biographical picture. + +His period of activity as a painter is traditionally limited to the two decades between 1639 and 1660, fitting within the generally accepted limits of the Dutch Golden Age's most significant period, 1640–1665. He is known to have been married to Cornelia Bosman in 1658, a date coinciding so directly with the end of his productivity as a painter that it has been accepted that his marriage played a role in the end of his artistic career. + +The year after his marriage, Cuyp became the deacon of the reformed church. Houbraken recalled that Cuyp was a devout Calvinist and the fact that when he died, there were no paintings of other artists found in his home. + +Style +The development of Cuyp, who was trained as a landscape painter, may be roughly sketched in three phases based on the painters who most influenced him during that time and the subsequent artistic characteristics that are apparent in his paintings. Generally, Cuyp learned tone from the exceptionally prolific Jan van Goyen, light from Jan Both and form from his father, Jacob Gerritsz Cuyp. + +Cuyp's "van Goyen phase" can be placed approximately in the early 1640s. Cuyp probably first encountered a painting by van Goyen in 1640 when van Goyen was, as Stephen Reiss points, out "at the height of [his] powers". This is noticeable in the comparison between two of Cuyp's landscape paintings inscribed 1639 where no properly formed style is apparent and the landscape backgrounds he painted two years later for two of his father's group portraits that are distinctly van Goyenesque. Cuyp took from van Goyen the straw yellow and light brown tones that are so apparent in his Dunes (1629) and the broken brush technique also very noticeable in that same work. This technique, a precursor to impressionism, is noted for the short brush strokes where the colors are not necessarily blended smoothly. In Cuyp's River Scene, Two Men Conversing (1641) both of these van Goyen-influenced stylistic elements are noticeable. + +The next phase in the development of Cuyp's increasingly amalgamated style is due to the influence of Jan Both. In the mid-1640s Both, a native and resident of Utrecht, had just returned to his hometown from a trip to Rome. It is around this same time that Cuyp's style changed fundamentally. In Rome, Both had developed a new style of composition due, at least in part, to his interaction with Claude Lorrain. This new style was focused on changing the direction of light in the painting. Instead of the light being placed at right angles in relation to the line of vision, Both started moving it to a diagonal position from the back of the picture. + +In this new form of lighting, the artist (and viewer of the painting) faced the sun more or less contre-jour. Both, and subsequently Cuyp, used the advantages of this new lighting style to alter the sense of depth and luminosity possible in a painting. To make notice of these new capabilities, much use was made of elongated shadows. Cuyp was one of the first Dutch painters to appreciate this new leap forward in style and while his own Both-inspired phase was quite short (limited to the mid-1640s) he did, more than any other contemporary Dutch artist, maximize the full chromatic scale for sunsets and sunrises.Cuyp's third stylistic phase (which occurred throughout his career) is based on the influence of his father. While it is assumed that the younger Cuyp did work with his father initially to develop rudimentary talents, Aelbert became more focused on landscape paintings while Jacob was a portrait painter by profession. As has been mentioned and as will be explained in depth below, there are pieces where Aelbert provided the landscape background for his father's portraits. What is meant by stating that Aelbert learned from his father is that his eventual transition from a specifically landscape painter to the involvement of foreground figures is attributed to his interaction with his father Jacob. The evidence for Aelbert's evolution to foreground figure painter is in the production of some paintings from 1645 to 1650 featuring foreground animals that do not fit with Jacob's style. Adding to the confusion regarding Aelbert's stylistic development and the problem of attribution is of course the fact that Jacob's style was not stagnant either. Their converging styles make it difficult to exactly understand the influences each had on the other, although it is clear enough to say that Aelbert started representing large scale forms (something he had not done previously) and placing animals as the focus of his paintings (something that was specific to him). + +Paintings +Sunlight in his paintings rakes across the panel, accentuating small bits of detail in the golden light. In large, atmospheric panoramas of the countryside, the highlights on a blade of meadow grass, the mane of a tranquil horse, the horn of a dairy cow reclining by a stream, or the tip of a peasant's hat are all caught in a bath of yellow ocher light. The richly varnished medium refracts the rays of light like a jewel as it dissolves into numerous glazed layers. Cuyp's landscapes were based on reality and on his own invention of what an enchanting landscape should be.Cuyp's drawings reveal him to be a draftsman of superior quality. Light-drenched washes of golden brown ink depict a distant view of the city of Dordrecht or Utrecht. +A Cuyp drawing may look like he intended it to be a finished work of art, but it was most likely taken back to the studio and used as a reference for his paintings. Often the same section of a sketch can be found in several different pictures. + +Cuyp signed many of his works but rarely dated them, so that a chronology of his career has not been satisfactorily reassembled. A phenomenal number of paintings are ascribed to him, some of which are likely to be by other masters of the golden landscape, such as Abraham Calraet (1642–1722), whose initials A.C. may be mistaken for Cuyp's. + +However, not everyone appreciates his work and River Landscape (1660), despite being widely regarded as amongst his best work, has been described as having "chocolate box blandness". + +At the Madrid's Thyssen-Bornemisza Museum most likely, the sole Cuyp's painting in Spanish public collections can be seen, a Landscape with a sunset ca. 1655 with animals. + +Misattribution of paintings + +In addition to the scarcely documented and confirmed biography of Cuyp's life, and even more so than his amalgamated style from his three main influences, there are yet other factors that have led to the misattribution and confusion over Aelbert Cuyp's works for hundreds of years. His highly influenced style which incorporated Italianate lighting from Jan Both, broken brush technique and atonality from Jan van Goyen, and his ever-developing style from his father Jacob Gerritsz Cuyp was studied acutely by his most prominent follower, Abraham van Calraet. Calraet mimicked Cuyp's style, incorporating the same aspects, and produced similar landscapes to that of the latter. This made it quite difficult to tell whose paintings were whose. Adding to the confusion is the similar initials between the two and the inconsistent signing of paintings which were produced by Cuyp's studio. + +Although Aelbert Cuyp signed many of his paintings with a script "A. Cuyp" insignia, many paintings were left unsigned (not to mention undated) after being painted, and so a similar signature was added later on, presumably by collectors who inherited or discovered the works. Furthermore, many possible Cuyp paintings were not signed but rather initialed "A. C." referring to his name. However, Abraham van Calraet could also have used the same initials to denote a painting. Although this is unlikely (as Calraet would likely have signed his paintings "A. v.C."), this brings up the question of how paintings were signed to show ownership. Most original Cuyp paintings were signed by him, and in the script manner in which his name was inscribed. This would denote that the painting was done almost entirely by him. Conversely, paintings which came out of his workshop that were not necessarily physically worked on by Cuyp but merely overseen by him technically, were marked with A.C. to show that it was his instruction which saw the paintings' completion. Cuyp's pupils and assistants often worked on paintings in his studio, and so most of the work of a painting could be done without Cuyp ever touching the canvas, but merely approving its finality. Hence, the initialed inscription rather than a signature. + +Common among the mislabeled works are all of the reasons identified for misattributing Cuyp's works: the lack of biography and chronology of his works made it difficult to discern when paintings were created (making it difficult to pinpoint an artist); contentious signatures added to historians' confusion as to who actually painted the works; and the collaborations and influences by different painters makes it hard to justify that a painting is genuinely that of Aelbert Cuyp; and finally, accurate identification is made extremely difficult by the fact that this same style was copied (rather accurately) by his predecessor. As it turns out, even the historians and expert researchers have been fooled and forced to reassess their conclusions over "Cuyp's" paintings over the years. + +Later life +After he married Cornelia Boschman in 1658, the number of works produced by him declined almost to nothing. This may have been because his wife was a very religious woman and a not very big patron of the arts. It could also be that he became more active in the church under his wife's guidance. He was also active as deacon and elder of the Reformed Church. + +Legacy +Though long lacking a modern biography, and with the chronology of his works rather unclear, his style emerged from various influences and makes his works distinctive, although his collaborations with his father and works by his imitators often make attributions uncertain. His follower Abraham van Calraet represents a particular problem, and the signatures on paintings are not to be relied on. The Rijksmuseum has reattributed many works to other painters; Abraham van Calraet does not even appear in a Museum catalogue until 1926, and even then he was not given his own entry. + +Gallery + +Notes + +References + +Further reading + + Gerard Hoet; Catalogus of Naamlyst van Schildereyen; The Hague; 1752; vol. 2 + Jean-Baptiste Descamps; La Vie des peintres flamands, allemands et hollandois; Paris; [n. pub.]; 1753–1763; vol. 2, p. 80 + George Agar-Ellis; Catalogue of the principal pictures in Flanders and Holland, 1822; London; W. Nicol; 1826; p. 70 + John Smith; A Catalogue Raisonne of the Works of the most Eminent Dutch, Flemish and French Painters Part III Containing the Lives and Works of Anthony Van Dyck and David Teniers; London; Smith and Son; 1831; vol. 5, no. 13 + Willem Bürger; Trésors d'Art exposés à Manchester en 1857; Paris; Jules Renouard et Cie; 1857; p. 266 + Jan F. van Someren; Oude Kunst in Nederland: Etsen van Willem Steelink; Amsterdam; [n. pub.]; 1890; pl. 3 + Emile Michel, Une famille d'artistes hollandais: Les Cuyps, Gazette des Beaux-Arts, 34, 1892, 5–23, 107–17, 224–38; p. 227 + Cornelis Hofstede de Groot; A Catalogue Raisonné of the Works of the Most Eminent Dutch Painters of the Seventeenth Century. Vols 1–4 [1907-1927]; Bishops Stortford; Chadwick Healey; 1976; vol. 2, no. 36 + Simon van Gijn; Dordracum Illustratum; Dordrecht; De Dordrechtsche Drukkerij-en Uitgevers-Maatschappij; 1908; no. 325 + Eugène Fromentin; The Masters of Past Time: Dutch and Flemish Painting from Van Eyck to Rembrandt [1948]; Oxford; Phaidon Press; 1981; p. 149 + Sir Francis Watson, The Art Collections at Waddesdon Manor I: The Paintings, Apollo, 69, June 1959, 172–182; p. 181 + Christopher White, Dutch and Flemish Paintings at Waddesdon Manor, Gazette des Beaux-Arts, 54, August 1959, 67–74; p. 68 + Ellis Waterhouse, Anthony Blunt; Paintings: The James A. de Rothschild Collection at Waddesdon Manor; Fribourg; Office du Livre, The National Trust; 1967; pp. 134–135, cat. no. 55 + J Q Van Regteren Altena, Review of The James A. de Rothschild Collection at Waddesdon Manor. Ellis Waterhouse, Paintings., Oud Holland, 85, 1970, 59–61; p. 60 + S. Reiss; Aelbert Cuyp; London; Zwemmer; 1975; p. 146, no. 106 + Margarita Russell, Aelbert Cuyp. The Maas at Dordrecht: The Great Assembly of the Dutch Armed Forces, June–July 1646., Dutch Crossing, 40, 1990, 31–82; pp. 34–35 + Ben Broos; Great Dutch Paintings from America; Zwolle; Waanders Publishers; 1990; p. 215 + Alan Chong; Aelbert Cuyp and the Meanings of Landscape; New York University; 1992; p. 408, cat. no. 160; as 'The gathering of the fleet at Dordrecht' + Arthur K Wheelock Jr.; Dutch Paintings of the Seventeenth Century: The National Gallery of Art's Systematic Catalogue; Washington, D.C.; National Gallery of Art; 1995; p. 129 + Ruud Priem, The "Most Excellent Collection" of Lucretia Johanna van Winter: The Years 1809–22, with a Catalogue of the Works Purchased, Simiolus: Netherlands Quarterly for the History of Art, 25, 1997, 103–196; p. 118, fig. 19 + Ruud Priem, Catalogue of Old Master Paintings Acquired by Lucretia Johanna van Winter, 1809–22, Simiolus: Netherlands Quarterly for the History of Art, 25, 1997, 197–230; p. 219, no. 38 + Arthur K Wheelock Jr.; Aelbert Cuyp; National Gallery of Art, Washington, 7 October 2001 – 13 January 2002; National Gallery, London, 13 February – 12 May 2002; Rijksmuseum, Amsterdam, 7 June – 1 September 2002; New York; Thames & Hudson; 2001; pp. 146–149 + Wouter Th. Kloek; Aelbert Cuyp: Land, Water, Light; Amsterdam, Zwolle; Rijksmuseum, Amsterdam, Waanders Publishers; 2002; p. 30 + Michael Hall; Waddesdon Manor: The Heritage of a Rothschild House; New York; Harry N Abrams Inc; 2002; p. 88, ill. + Ariane van Suchtelen, Arthur K Wheelock Jr.; Dutch Cityscapes of the Golden Age; Royal Picture Gallery Mauritshuis, The Hague, 11 October 2008 – 11 January 2009; National Gallery of Art, Washington, 1 February – 3 May 2009; Zwolle, Washington, D.C., The Hague; Waanders Publishers, National Gallery of Art, Royal Picture Gallery Mauritshuis, The Hague; 2008; p. 104, ill. + Peter Hecht; 125 Jaar openbaar kunstbezit : met steun van de Vereniging Rembrandt; Zwolle; Waanders Publishers; 2008; pp. 12, 14, 209 n. 98 + Arthur K Wheelock Jr.; "Aelbert Cuyp/The Maas at Dordrecht/c. 1650", Dutch Paintings of the Seventeenth Century, NGA Online Editions, accessed December 07, 2014.; Washington, D.C.; National Gallery of Art; 2012 + +External links + +Works and literature on Aelbert Cuyp +Dutch and Flemish paintings from the Hermitage, an exhibition catalog from The Metropolitan Museum of Art (fully available online as PDF), which contains material on Cuyp (cat. no. 7) +Aelbert Cuyp's artworks at Waddesdon Manor + +1620 births +1691 deaths +Dutch Golden Age painters +Dutch male painters +Dutch landscape painters +Dutch Calvinist and Reformed Christians +Artists from Dordrecht +Waddesdon Manor +In organic chemistry, an alkene is a hydrocarbon containing a carbon–carbon double bond. The double bond may be internal or in the terminal position. Terminal alkenes are also known as α-olefins. + +The International Union of Pure and Applied Chemistry (IUPAC) recommends using the name "alkene" only for acyclic hydrocarbons with just one double bond; alkadiene, alkatriene, etc., or polyene for acyclic hydrocarbons with two or more double bonds; cycloalkene, cycloalkadiene, etc. for cyclic ones; and "olefin" for the general class – cyclic or acyclic, with one or more double bonds. + +Acyclic alkenes, with only one double bond and no other functional groups (also known as mono-enes) form a homologous series of hydrocarbons with the general formula with n being 2 or more (which is two hydrogens less than the corresponding alkane). When n is four or more, isomers are possible, distinguished by the position and conformation of the double bond. + +Alkenes are generally colorless non-polar compounds, somewhat similar to alkanes but more reactive. The first few members of the series are gases or liquids at room temperature. The simplest alkene, ethylene () (or "ethene" in the IUPAC nomenclature) is the organic compound produced on the largest scale industrially. + +Aromatic compounds are often drawn as cyclic alkenes, however their structure and properties are sufficiently distinct that they are not classified as alkenes or olefins. Hydrocarbons with two overlapping double bonds () are called allenes—the simplest such compound is itself called allene—and those with three or more overlapping bonds (, , etc.) are called cumulenes. + +Structural isomerism +Alkenes having four or more carbon atoms can form diverse structural isomers. Most alkenes are also isomers of cycloalkanes. Acyclic alkene structural isomers with only one double bond follow: + + : ethylene only + : propylene only + : 3 isomers: 1-butene, 2-butene, and isobutylene + : 5 isomers: 1-pentene, 2-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene + : 13 isomers: 1-hexene, 2-hexene, 3-hexene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 2-methyl-2-pentene, 3-methyl-2-pentene, 4-methyl-2-pentene, 2,3-dimethyl-1-butene, 3,3-dimethyl-1-butene, 2,3-dimethyl-2-butene, 2-ethyl-1-butene + +Many of these molecules exhibit cis–trans isomerism. There may also be chiral carbon atoms particularly within the larger molecules (from ). The number of potential isomers increases rapidly with additional carbon atoms. + +Structure and bonding + +Bonding + +A carbon–carbon double bond consists of a sigma bond and a pi bond. This double bond is stronger than a single covalent bond (611 kJ/mol for C=C vs. 347 kJ/mol for C–C), but not twice as strong. Double bonds are shorter than single bonds with an average bond length of 1.33 Å (133 pm) vs 1.53 Å for a typical C-C single bond. + +Each carbon atom of the double bond uses its three sp2 hybrid orbitals to form sigma bonds to three atoms (the other carbon atom and two hydrogen atoms). The unhybridized 2p atomic orbitals, which lie perpendicular to the plane created by the axes of the three sp2 hybrid orbitals, combine to form the pi bond. This bond lies outside the main C–C axis, with half of the bond on one side of the molecule and a half on the other. With a strength of 65 kcal/mol, the pi bond is significantly weaker than the sigma bond. + +Rotation about the carbon–carbon double bond is restricted because it incurs an energetic cost to break the alignment of the p orbitals on the two carbon atoms. Consequently cis or trans isomers interconvert so slowly that they can be freely handled at ambient conditions without isomerization. More complex alkenes may be named with the E–Z notation for molecules with three or four different substituents (side groups). For example, of the isomers of butene, the two methyl groups of (Z)-but-2-ene (a.k.a. cis-2-butene) appear on the same side of the double bond, and in (E)-but-2-ene (a.k.a. trans-2-butene) the methyl groups appear on opposite sides. These two isomers of butene have distinct properties. + +Shape +As predicted by the VSEPR model of electron pair repulsion, the molecular geometry of alkenes includes bond angles about each carbon atom in a double bond of about 120°. The angle may vary because of steric strain introduced by nonbonded interactions between functional groups attached to the carbon atoms of the double bond. For example, the C–C–C bond angle in propylene is 123.9°. + +For bridged alkenes, Bredt's rule states that a double bond cannot occur at the bridgehead of a bridged ring system unless the rings are large enough. Following Fawcett and defining S as the total number of non-bridgehead atoms in the rings, bicyclic systems require S ≥ 7 for stability and tricyclic systems require S ≥ 11. + +Isomerism + +In organic chemistry,the prefixes cis- and trans- are used to describe the positions of functional groups attached to carbon atoms joined by a double bond. In Latin, cis and trans mean "on this side of" and "on the other side of" respectively. Therefore, if the functional groups are both on the same side of the carbon chain, the bond is said to have cis- configuration, otherwise (i.e. the functional groups are on the opposite side of the carbon chain), the bond is said to have trans- configuration. + +For there to be cis- and trans- configurations, there must be a carbon chain, or at least one functional group attached to each carbon is the same for both. E- and Z- configuration can be used instead in a more general case where all four functional groups attached to carbon atoms in a double bond are different. E- and Z- are abbreviations of German words zusammen (together) and entgegen (opposite). In E- and Z-isomerism, each functional group is assigned a priority based on the Cahn–Ingold–Prelog priority rules. If the two groups with higher priority are on the same side of the double bond, the bond is assigned Z- configuration, otherwise (i.e. the two groups with higher priority are on the opposite side of the double bond), the bond is assigned E- configuration. Cis- and trans- configurations do not have a fixed relationship with E- and Z-configurations. + +Physical properties +Many of the physical properties of alkenes and alkanes are similar: they are colorless, nonpolar, and combustible. The physical state depends on molecular mass: like the corresponding saturated hydrocarbons, the simplest alkenes (ethylene, propylene, and butene) are gases at room temperature. Linear alkenes of approximately five to sixteen carbon atoms are liquids, and higher alkenes are waxy solids. The melting point of the solids also increases with increase in molecular mass. + +Alkenes generally have stronger smells than their corresponding alkanes. Ethylene has a sweet and musty odor. Strained alkenes, in particular, like norbornene and trans-cyclooctene are known to have strong, unpleasant odors, a fact consistent with the stronger π complexes they form with metal ions including copper. + +Boiling and melting points +Below is a list of the boiling and melting points of various alkenes with the corresponding alkane and alkyne analogues. + +Infrared spectroscopy +The stretching of C=C bond will give an IR absorption peak at 1670–1600 cm−1, while the bending of C=C bond absorbs between 1000 and 650 cm−1 wavelength. + +NMR spectroscopy +In 1H NMR spectroscopy, the hydrogen bonded to the carbon adjacent to double bonds will give a δH of 4.5–6.5 ppm. The double bond will also deshield the hydrogen attached to the carbons adjacent to sp2 carbons, and this generates δH=1.6–2. ppm peaks. Cis/trans isomers are distinguishable due to different J-coupling effect. Cis vicinal hydrogens will have coupling constants in the range of 6–14 Hz, whereas the trans will have coupling constants of 11–18 Hz. + +In their 13C NMR spectra of alkenes, double bonds also deshield the carbons, making them have low field shift. C=C double bonds usually have chemical shift of about 100–170 ppm. + +Combustion +Like most other hydrocarbons, alkenes combust to give carbon dioxide and water. + +The combustion of alkenes release less energy than burning same molarity of saturated ones with same number of carbons. +This trend can be clearly seen in the list of standard enthalpy of combustion of hydrocarbons. + +Reactions +Alkenes are relatively stable compounds, but are more reactive than alkanes. Most reactions of alkenes involve additions to this pi bond, forming new single bonds. Alkenes serve as a feedstock for the petrochemical industry because they can participate in a wide variety of reactions, prominently polymerization and alkylation. Except for ethylene, alkenes have two sites of reactivity: the carbon–carbon pi-bond and the presence of allylic CH centers. The former dominates but the allylic sites are important too. + +Addition to the unsaturated bonds + +Hydrogenation involves the addition of H2 resulting in an alkane. The equation of hydrogenation of ethylene to form ethane is: +H2C=CH2 + H2→H3C−CH3 +Hydrogenation reactions usually require catalysts to increase their reaction rate. The total number of hydrogens that can be added to an unsaturated hydrocarbon depends on its degree of unsaturation. + +Similar to hydrogen, halogens added to double bonds. +H2C=CH2 + Br2→H2CBr−CH2Br +Halonium ions are intermediates. These reactions do not require catalysts. + +Bromine test is used to test the saturation of hydrocarbons. The bromine test can also be used as an indication of the degree of unsaturation for unsaturated hydrocarbons. Bromine number is defined as gram of bromine able to react with 100g of product. Similar as hydrogenation, the halogenation of bromine is also depend on the number of π bond. A higher bromine number indicates higher degree of unsaturation. + +The π bonds of alkenes hydrocarbons are also susceptible to hydration. The reaction usually involves strong acid as catalyst. The first step in hydration often involves formation of a carbocation. The net result of the reaction will be an alcohol. The reaction equation for hydration of ethylene is: +H2C=CH2 + H2O→ + +Hydrohalogenation involves addition of H−X to unsaturated hydrocarbons. This reaction results in new C−H and C−X σ bonds. The formation of the intermediate carbocation is selective and follows Markovnikov's rule. The hydrohalogenation of alkene will result in haloalkane. The reaction equation of HBr addition to ethylene is: +H2C=CH2 + HBr → + +Cycloaddition + +Alkenes add to dienes to give cyclohexenes. This conversion is an example of a Diels-Alder reaction. Such reaction proceed with retention of stereochemistry. The rates are sensitive to electron-withdrawing or electron-donating substituents. When irradiated by UV-light, alkenes dimerize to give cyclobutanes. Another example is the Schenck ene reaction, in which singlet oxygen reacts with an allylic structure to give a transposed allyl peroxide: + +Oxidation +Alkenes react with percarboxylic acids and even hydrogen peroxide to yield epoxides: + +For ethylene, the epoxidation is conducted on a very large scale industrially using oxygen in the presence of silver-based catalysts: + +Alkenes react with ozone, leading to the scission of the double bond. The process is called ozonolysis. Often the reaction procedure includes a mild reductant, such as dimethylsulfide (): + +When treated with a hot concentrated, acidified solution of , alkenes are cleaved to form ketones and/or carboxylic acids. The stoichiometry of the reaction is sensitive to conditions. This reaction and the ozonolysis can be used to determine the position of a double bond in an unknown alkene. + +The oxidation can be stopped at the vicinal diol rather than full cleavage of the alkene by using osmium tetroxide or other oxidants: +R'CH=CR2 + 1/2 O2 + H2O -> R'CH(OH)-C(OH)R2 +This reaction is called dihydroxylation. + +In the presence of an appropriate photosensitiser, such as methylene blue and light, alkenes can undergo reaction with reactive oxygen species generated by the photosensitiser, such as hydroxyl radicals, singlet oxygen or superoxide ion. Reactions of the excited sensitizer can involve electron or hydrogen transfer, usually with a reducing substrate (Type I reaction) or interaction with oxygen (Type II reaction). These various alternative processes and reactions can be controlled by choice of specific reaction conditions, leading to a wide range of products. A common example is the [4+2]-cycloaddition of singlet oxygen with a diene such as cyclopentadiene to yield an endoperoxide: + +Polymerization + +Terminal alkenes are precursors to polymers via processes termed polymerization. Some polymerizations are of great economic significance, as they generate the plastics polyethylene and polypropylene. Polymers from alkene are usually referred to as polyolefins although they contain no olefins. Polymerization can proceed via diverse mechanisms. Conjugated dienes such as buta-1,3-diene and isoprene (2-methylbuta-1,3-diene) also produce polymers, one example being natural rubber. + +Allylic substitution +The presence of a C=C π bond in unsaturated hydrocarbons weakens the dissociation energy of the allylic C−H bonds. Thus, these groupings are susceptible to free radical substitution at these C-H sites as well as addition reactions at the C=C site. In the presence of radical initiators, allylic C-H bonds can be halogenated. The presence of two C=C bonds flanking one methylene, i.e., doubly allylic, results in particularly weak HC-H bonds. The high reactivity of these situations is the basis for certain free radical reactions, manifested in the chemistry of drying oils. + +Metathesis +Alkenes undergo olefin metathesis, which cleaves and interchanges the substituents of the alkene. A related reaction is ethenolysis: + +Metal complexation + +In transition metal alkene complexes, alkenes serve as ligands for metals. In this case, the π electron density is donated to the metal d orbitals. The stronger the donation is, the stronger the back bonding from the metal d orbital to π* anti-bonding orbital of the alkene. This effect lowers the bond order of the alkene and increases the C-C bond length. One example is the complex . These complexes are related to the mechanisms of metal-catalyzed reactions of unsaturated hydrocarbons. + +Reaction overview + +Synthesis + +Industrial methods +Alkenes are produced by hydrocarbon cracking. Raw materials are mostly natural gas condensate components (principally ethane and propane) in the US and Mideast and naphtha in Europe and Asia. Alkanes are broken apart at high temperatures, often in the presence of a zeolite catalyst, to produce a mixture of primarily aliphatic alkenes and lower molecular weight alkanes. The mixture is feedstock and temperature dependent, and separated by fractional distillation. This is mainly used for the manufacture of small alkenes (up to six carbons). + +Related to this is catalytic dehydrogenation, where an alkane loses hydrogen at high temperatures to produce a corresponding alkene. This is the reverse of the catalytic hydrogenation of alkenes. + +This process is also known as reforming. Both processes are endothermic and are driven towards the alkene at high temperatures by entropy. + +Catalytic synthesis of higher α-alkenes (of the type RCH=CH2) can also be achieved by a reaction of ethylene with the organometallic compound triethylaluminium in the presence of nickel, cobalt, or platinum. + +Elimination reactions +One of the principal methods for alkene synthesis in the laboratory is the room elimination of alkyl halides, alcohols, and similar compounds. Most common is the β-elimination via the E2 or E1 mechanism, but α-eliminations are also known. + +The E2 mechanism provides a more reliable β-elimination method than E1 for most alkene syntheses. Most E2 eliminations start with an alkyl halide or alkyl sulfonate ester (such as a tosylate or triflate). When an alkyl halide is used, the reaction is called a dehydrohalogenation. For unsymmetrical products, the more substituted alkenes (those with fewer hydrogens attached to the C=C) tend to predominate (see Zaitsev's rule). Two common methods of elimination reactions are dehydrohalogenation of alkyl halides and dehydration of alcohols. A typical example is shown below; note that if possible, the H is anti to the leaving group, even though this leads to the less stable Z-isomer. + +Alkenes can be synthesized from alcohols via dehydration, in which case water is lost via the E1 mechanism. For example, the dehydration of ethanol produces ethylene: +CH3CH2OH → H2C=CH2 + H2O + +An alcohol may also be converted to a better leaving group (e.g., xanthate), so as to allow a milder syn-elimination such as the Chugaev elimination and the Grieco elimination. Related reactions include eliminations by β-haloethers (the Boord olefin synthesis) and esters (ester pyrolysis). + +Alkenes can be prepared indirectly from alkyl amines. The amine or ammonia is not a suitable leaving group, so the amine is first either alkylated (as in the Hofmann elimination) or oxidized to an amine oxide (the Cope reaction) to render a smooth elimination possible. The Cope reaction is a syn-elimination that occurs at or below 150 °C, for example: + +The Hofmann elimination is unusual in that the less substituted (non-Zaitsev) alkene is usually the major product. + +Alkenes are generated from α-halosulfones in the Ramberg–Bäcklund reaction, via a three-membered ring sulfone intermediate. + +Synthesis from carbonyl compounds +Another important method for alkene synthesis involves construction of a new carbon–carbon double bond by coupling of a carbonyl compound (such as an aldehyde or ketone) to a carbanion equivalent. Such reactions are sometimes called olefinations. The most well-known of these methods is the Wittig reaction, but other related methods are known, including the Horner–Wadsworth–Emmons reaction. + +The Wittig reaction involves reaction of an aldehyde or ketone with a Wittig reagent (or phosphorane) of the type Ph3P=CHR to produce an alkene and Ph3P=O. The Wittig reagent is itself prepared easily from triphenylphosphine and an alkyl halide. The reaction is quite general and many functional groups are tolerated, even esters, as in this example: + +Related to the Wittig reaction is the Peterson olefination, which uses silicon-based reagents in place of the phosphorane. This reaction allows for the selection of E- or Z-products. If an E-product is desired, another alternative is the Julia olefination, which uses the carbanion generated from a phenyl sulfone. The Takai olefination based on an organochromium intermediate also delivers E-products. A titanium compound, Tebbe's reagent, is useful for the synthesis of methylene compounds; in this case, even esters and amides react. + +A pair of ketones or aldehydes can be deoxygenated to generate an alkene. Symmetrical alkenes can be prepared from a single aldehyde or ketone coupling with itself, using titanium metal reduction (the McMurry reaction). If different ketones are to be coupled, a more complicated method is required, such as the Barton–Kellogg reaction. + +A single ketone can also be converted to the corresponding alkene via its tosylhydrazone, using sodium methoxide (the Bamford–Stevens reaction) or an alkyllithium (the Shapiro reaction). + +Synthesis from alkenes +The formation of longer alkenes via the step-wise polymerisation of smaller ones is appealing, as ethylene (the smallest alkene) is both inexpensive and readily available, with hundreds of millions of tonnes produced annually. The Ziegler–Natta process allows for the formation of very long chains, for instance those used for polyethylene. Where shorter chains are wanted, as they for the production of surfactants, then processes incorporating a olefin metathesis step, such as the Shell higher olefin process are important. + +Olefin metathesis is also used commercially for the interconversion of ethylene and 2-butene to propylene. Rhenium- and molybdenum-containing heterogeneous catalysis are used in this process: +CH2=CH2 + CH3CH=CHCH3 → 2 CH2=CHCH3 + +Transition metal catalyzed hydrovinylation is another important alkene synthesis process starting from alkene itself. It involves the addition of a hydrogen and a vinyl group (or an alkenyl group) across a double bond. + +From alkynes +Reduction of alkynes is a useful method for the stereoselective synthesis of disubstituted alkenes. If the cis-alkene is desired, hydrogenation in the presence of Lindlar's catalyst (a heterogeneous catalyst that consists of palladium deposited on calcium carbonate and treated with various forms of lead) is commonly used, though hydroboration followed by hydrolysis provides an alternative approach. Reduction of the alkyne by sodium metal in liquid ammonia gives the trans-alkene. + +For the preparation multisubstituted alkenes, carbometalation of alkynes can give rise to a large variety of alkene derivatives. + +Rearrangements and related reactions +Alkenes can be synthesized from other alkenes via rearrangement reactions. Besides olefin metathesis (described above), many pericyclic reactions can be used such as the ene reaction and the Cope rearrangement. + +In the Diels–Alder reaction, a cyclohexene derivative is prepared from a diene and a reactive or electron-deficient alkene. + +Application +Unsaturated hydrocarbons are widely used to produce plastics, medicines, and other useful materials. + +Natural occurrence +Alkenes are pervasive in nature. +Plants are the main natural source of alkenes in the form of terpenes. Many of the most vivid natural pigments are terpenes; e.g. lycopene (red in tomatoes) and carotene (orange of carrots). The simplest of all alkenes, ethylene (plant hormone) is a signaling molecule that influences the ripening of plants. + +IUPAC Nomenclature +Although the nomenclature is not followed widely, according to IUPAC, an alkene is an acyclic hydrocarbon with just one double bond between carbon atoms. Olefins comprise a larger collection of cyclic and acyclic alkenes as well as dienes and polyenes. + +To form the root of the IUPAC names for straight-chain alkenes, change the -an- infix of the parent to -en-. For example, CH3-CH3 is the alkane ethANe. The name of CH2=CH2 is therefore ethENe. + +For straight-chain alkenes with 4 or more carbon atoms, that name does not completely identify the compound. For those cases, and for branched acyclic alkenes, the following rules apply: + Find the longest carbon chain in the molecule. If that chain does not contain the double bond, name the compound according to the alkane naming rules. Otherwise: + Number the carbons in that chain starting from the end that is closest to the double bond. + Define the location k of the double bond as being the number of its first carbon. + Name the side groups (other than hydrogen) according to the appropriate rules. + Define the position of each side group as the number of the chain carbon it is attached to. + Write the position and name of each side group. + Write the names of the alkane with the same chain, replacing the "-ane" suffix by "k-ene". + +The position of the double bond is often inserted before the name of the chain (e.g. "2-pentene"), rather than before the suffix ("pent-2-ene"). + +The positions need not be indicated if they are unique. Note that the double bond may imply a different chain numbering than that used for the corresponding alkane: C–– is "2,2-dimethyl pentane", whereas C–= is "3,3-dimethyl 1-pentene". + +More complex rules apply for polyenes and cycloalkenes. + +Cis–trans isomerism +If the double bond of an acyclic mono-ene is not the first bond of the chain, the name as constructed above still does not completely identify the compound, because of cis–trans isomerism. Then one must specify whether the two single C–C bonds adjacent to the double bond are on the same side of its plane, or on opposite sides. For monoalkenes, the configuration is often indicated by the prefixes cis- (from Latin "on this side of") or trans- ("across", "on the other side of") before the name, respectively; as in cis-2-pentene or trans-2-butene. + +More generally, cis–trans isomerism will exist if each of the two carbons of in the double bond has two different atoms or groups attached to it. Accounting for these cases, the IUPAC recommends the more general E–Z notation, instead of the cis and trans prefixes. This notation considers the group with highest CIP priority in each of the two carbons. If these two groups are on opposite sides of the double bond's plane, the configuration is labeled E (from the German entgegen meaning "opposite"); if they are on the same side, it is labeled Z (from German zusammen, "together"). This labeling may be taught with mnemonic "Z means 'on ze zame zide'". + +Groups containing C=C double bonds +IUPAC recognizes two names for hydrocarbon groups containing carbon–carbon double bonds, the vinyl group and the allyl group. + +See also + + Alpha-olefin + Annulene + Aromatic hydrocarbon ("Arene") + Dendralene + Nitroalkene + Radialene + +Nomenclature links + Rule A-3. Unsaturated Compounds and Univalent Radicals IUPAC Blue Book. + Rule A-4. Bivalent and Multivalent Radicals IUPAC Blue Book. + Rules A-11.3, A-11.4, A-11.5 Unsaturated monocyclic hydrocarbons and substituents IUPAC Blue Book. + Rule A-23. Hydrogenated Compounds of Fused Polycyclic Hydrocarbons IUPAC Blue Book. + +References +In organic chemistry, allenes are organic compounds in which one carbon atom has double bonds with each of its two adjacent carbon atoms (, where R is H or some organyl group). Allenes are classified as cumulated dienes. The parent compound of this class is propadiene (), which is itself also called allene. An group of the structure is called allenyl, where R is H or some alkyl group. Compounds with an allene-type structure but with more than three carbon atoms are members of a larger class of compounds called cumulenes with bonding. + +History +For many years, allenes were viewed as curiosities but thought to be synthetically useless and difficult to prepare and to work with. Reportedly, the first synthesis of an allene, glutinic acid, was performed in an attempt to prove the non-existence of this class of compounds. The situation began to change in the 1950s, and more than 300 papers on allenes have been published in 2012 alone. These compounds are not just interesting intermediates but synthetically valuable targets themselves; for example, over 150 natural products are known with an allene or cumulene fragment. + +Structure and properties + +Geometry + +The central carbon atom of allenes forms two sigma bonds and two pi bonds. The central carbon atom is sp-hybridized, and the two terminal carbon atoms are sp2-hybridized. The bond angle formed by the three carbon atoms is 180°, indicating linear geometry for the central carbon atom. The two terminal carbon atoms are planar, and these planes are twisted 90° from each other. The structure can also be viewed as an "extended tetrahedral" with a similar shape to methane, an analogy that is continued into the stereochemical analysis of certain derivative molecules. + +Symmetry + +The symmetry and isomerism of allenes has long fascinated organic chemists. For allenes with four identical substituents, there exist two twofold axes of rotation through the central carbon atom, inclined at 45° to the CH2 planes at either end of the molecule. The molecule can thus be thought of as a two-bladed propeller. A third twofold axis of rotation passes through the C=C=C bonds, and there is a mirror plane passing through both CH2 planes. Thus this class of molecules belong to the D2d point group. Because of the symmetry, an unsubstituted allene has no net dipole moment, that is, it is a non-polar molecule. + +An allene with two different substituents on each of the two carbon atoms will be chiral because there will no longer be any mirror planes. The chirality of these types of allenes was first predicted in 1875 by Jacobus Henricus van 't Hoff, but not proven experimentally until 1935. Where A has a greater priority than B according to the Cahn–Ingold–Prelog priority rules, the configuration of the axial chirality can be determined by considering the substituents on the front atom followed by the back atom when viewed along the allene axis. For the back atom, only the group of higher priority need be considered. + +Chiral allenes have been recently used as building blocks in the construction of organic materials with exceptional chiroptical properties. There are a few examples of drug molecule having an allene system in their structure.  Mycomycin, an antibiotic with tuberculostatic properties, is a typical example. This drug exhibits enantiomerism due to the presence of a suitably substituted allene system. + +Although the semi-localized textbook σ-π separation model describes the bonding of allene using a pair of localized orthogonal π orbitals, the full molecular orbital description of the bonding is more subtle. The symmetry-correct doubly-degenerate HOMOs of allene (adapted to the D2d point group) can either be represented by a pair of orthogonal MOs or as twisted helical linear combinations of these orthogonal MOs. The symmetry of the system and the degeneracy of these orbitals imply that both descriptions are correct (in the same way that there are infinitely many ways to depict the doubly-degenerate HOMOs and LUMOs of benzene that correspond to different choices of eigenfunctions in a two-dimensional eigenspace). However, this degeneracy is lifted in substituted allenes, and the helical picture becomes the only symmetry-correct description for the HOMO and HOMO–1 of the C2-symmetric 1,3-dimethylallene. This qualitative MO description extends to higher odd-carbon cumulenes (e.g., 1,2,3,4-pentatetraene). + +Chemical and spectral properties +Allenes differ considerably from other alkenes in terms of their chemical properties. Compared to isolated and conjugated dienes, they are considerably less stable: comparing the isomeric pentadienes, the allenic 1,2-pentadiene has a heat of formation of 33.6 kcal/mol, compared to 18.1 kcal/mol for (E)-1,3-pentadiene and 25.4 kcal/mol for the isolated 1,4-pentadiene. + +The C–H bonds of allenes are considerably weaker and more acidic compared to typical vinylic C–H bonds: the bond dissociation energy is 87.7 kcal/mol (compared to 111 kcal/mol in ethylene), while the gas-phase acidity is 381 kcal/mol (compared to 409 kcal/mol for ethylene), making it slightly more acidic than the propargylic C–H bond of propyne (382 kcal/mol). + +The 13C NMR spectrum of allenes is characterized by the signal of the sp-hybridized carbon atom, resonating at a characteristic 200-220 ppm. In contrast, the sp2-hybridized carbon atoms resonate around 80 ppm in a region typical for alkyne and nitrile carbon atoms, while the protons of a CH2 group of a terminal allene resonate at around 4.5 ppm — somewhat upfield of a typical vinylic proton. + +Allenes possess a rich cycloaddition chemistry, including both [4+2] and [2+2] modes of addition, as well as undergoing formal cycloaddition processes catalyzed by transition metals. Allenes also serve as substrates for transition metal catalyzed hydrofunctionalization reactions. + +Synthesis +Although allenes often require specialized syntheses, the parent allene, propadiene is produced industrially on a large scale as an equilibrium mixture with methylacetylene: +H2C=C=CH2 <=> H3C-C#CH +This mixture, known as MAPP gas, is commercially available. At 298 K, the ΔG° of this reaction is –1.9 kcal/mol, corresponding to Keq = 24.7. + +The first allene to be synthesized was penta-2,3-dienedioic acid, which was prepared by Burton and Pechmann in 1887. However, the structure was only correctly identified in 1954. + +Laboratory methods for the formation of allenes include: +from geminal dihalocyclopropanes and organolithium compounds (or metallic sodium or magnesium) in the Skattebøl rearrangement (Doering–LaFlamme allene synthesis) via rearrangement of cyclopropylidene carbenes/carbenoids +from reaction of certain terminal alkynes with formaldehyde, copper(I) bromide, and added base (Crabbé–Ma allene synthesis) +from propargylic halides by SN2′ displacement by an organocuprate +from dehydrohalogenation of certain dihalides +from reaction of a triphenylphosphinyl ester with an acid halide, a Wittig reaction accompanied by dehydrohalogenation +from propargylic alcohols via the Myers allene synthesis protocol—a stereospecific process +from metalation of allene or substituted allenes with BuLi and reaction with electrophiles (RX, R3SiX, D2O, etc.) +The chemistry of allenes has been reviewed in a number of books and journal articles. Some key approaches towards allenes are outlined in the following scheme: + +One of the older methods is the Skattebøl rearrangement (also called the Doering–Moore–Skattebøl or Doering–LaFlamme rearrangement), in which a gem-dihalocyclopropane 3 is treated with an organolithium compound (or dissolving metal) and the presumed intermediate rearranges into an allene either directly or via carbene-like species. Notably, even strained allenes can be generated by this procedure. Modifications involving leaving groups of different nature are also known. Arguably, the most convenient modern method of allene synthesis is by sigmatropic rearrangement of propargylic substrates. Johnson–Claisen and Ireland–Claisen rearrangements of ketene acetals 4 have been used a number of times to prepare allenic esters and acids. Reactions of vinyl ethers 5 (the Saucy–Marbet rearrangement) give allene aldehydes, while propargylic sulfenates 6 give allene sulfoxides. Allenes can also be prepared by nucleophilic substitution in 9 and 10 (nucleophile Nu− can be a hydride anion), 1,2-elimination from 8, proton transfer in 7, and other, less general, methods. + +Use and occurrence + +The dominant use of allenes is allene itself, which, in equilibrium with propyne is a component of MAP gas. + +Research +The reactivity of substituted allenes has been well explored. + +The two π-bonds are located at the 90° angle to each other, and thus require a reagent to approach from somewhat different directions. With an appropriate substitution pattern, allenes exhibit axial chirality as predicted by van’t Hoff as early as 1875. Protonation of allenes gives cations 11 that undergo further transformations. Reactions with soft electrophiles (e.g. Br+) deliver positively charged onium ions 13. Transition-metal-catalysed reactions proceed via allylic intermediates 15 and have attracted significant interest in recent years. Numerous cycloadditions are also known, including [4+2]-, (2+1)-, and [2+2]-variants, which deliver, e.g., 12, 14, and 16, respectively. + +Occurrence + +Numerous natural products contain the allene functional group. Noteworthy are the pigments fucoxanthin and peridinin. Little is known about the biosynthesis, although it is conjectured that they are often generated from alkyne precursors. + +Allenes serve as ligands in organometallic chemistry. A typical complex is Pt(η2-allene)(PPh3)2. Ni(0) reagents catalyze the cyclooligomerization of allene. Using a suitable catalyst (e.g. Wilkinson's catalyst), it is possible to reduce just one of the double bonds of an allene. + +Delta convention +Many rings or ring systems are known by semisystematic names that assume a maximum number of noncumulative bonds. To unambiguously specify derivatives that include cumulated bonds (and hence fewer hydrogen atoms than would be expected from the skeleton), a lowercase delta may be used with a subscript indicating the number of cumulated double bonds from that atom, e.g. 8δ2-benzocyclononene. This may be combined with the λ-convention for specifying nonstandard valency states, e.g. 2λ4δ2,5λ4δ2-thieno[3,4-c]thiophene. + +See also +Compounds with three or more adjacent carbon–carbon double bonds are called cumulenes. + +References + +Further reading + Brummond, Kay M. (editor). Allene chemistry (special thematic issue). Beilstein Journal of Organic Chemistry 7: 394–943. + +External links +Synthesis of allenes + +Jacobus Henricus van 't Hoff +Acetylene + +Propyne + +1-Butyne + +In organic chemistry, an alkyne is an unsaturated hydrocarbon containing at least one carbon—carbon triple bond. The simplest acyclic alkynes with only one triple bond and no other functional groups form a homologous series with the general chemical formula . Alkynes are traditionally known as acetylenes, although the name acetylene also refers specifically to , known formally as ethyne using IUPAC nomenclature. Like other hydrocarbons, alkynes are generally hydrophobic. + +Structure and bonding +In acetylene, the H–C≡C bond angles are 180°. By virtue of this bond angle, alkynes are rod-like. Correspondingly, cyclic alkynes are rare. Benzyne cannot be isolated. The C≡C bond distance of 118 picometers (for C2H2) is much shorter than the C=C distance in alkenes (132 pm, for C2H4) or the C–C bond in alkanes (153 pm). + +The triple bond is very strong with a bond strength of 839 kJ/mol. The sigma bond contributes 369 kJ/mol, the first pi bond contributes 268 kJ/mol and the second pi-bond of 202 kJ/mol bond strength. Bonding usually discussed in the context of molecular orbital theory, which recognizes the triple bond as arising from overlap of s and p orbitals. In the language of valence bond theory, the carbon atoms in an alkyne bond are sp hybridized: they each have two unhybridized p orbitals and two sp hybrid orbitals. Overlap of an sp orbital from each atom forms one sp–sp sigma bond. Each p orbital on one atom overlaps one on the other atom, forming two pi bonds, giving a total of three bonds. The remaining sp orbital on each atom can form a sigma bond to another atom, for example to hydrogen atoms in the parent acetylene. The two sp orbitals project on opposite sides of the carbon atom. + +Terminal and internal alkynes +Internal alkynes feature carbon substituents on each acetylenic carbon. Symmetrical examples include diphenylacetylene and 3-hexyne. + +Terminal alkynes have the formula . An example is methylacetylene (propyne using IUPAC nomenclature). They are often prepared by alkylation of monosodium acetylide. This compound, a white solid, has been characterized by Terminal alkynes, like acetylene itself, are mildly acidic, with pKa values of around 25. They are far more acidic than alkenes and alkanes, which have pKa values of around 40 and 50, respectively. The acidic hydrogen on terminal alkynes can be replaced by a variety of groups resulting in halo-, silyl-, and alkoxoalkynes. The carbanions generated by deprotonation of terminal alkynes are called acetylides. + +Naming alkynes +In systematic chemical nomenclature, alkynes are named with the Greek prefix system without any additional letters. Examples include ethyne or octyne. In parent chains with four or more carbons, it is necessary to say where the triple bond is located. For octyne, one can either write 3-octyne or oct-3-yne when the bond starts at the third carbon. The lowest number possible is given to the triple bond. When no superior functional groups are present, the parent chain must include the triple bond even if it is not the longest possible carbon chain in the molecule. Ethyne is commonly called by its trivial name acetylene. + +In chemistry, the suffix -yne is used to denote the presence of a triple bond. In organic chemistry, the suffix often follows IUPAC nomenclature. However, inorganic compounds featuring unsaturation in the form of triple bonds may be denoted by substitutive nomenclature with the same methods used with alkynes (i.e. the name of the corresponding saturated compound is modified by replacing the "-ane" ending with "-yne"). "-diyne" is used when there are two triple bonds, and so on. The position of unsaturation is indicated by a numerical locant immediately preceding the "-yne" suffix, or 'locants' in the case of multiple triple bonds. Locants are chosen so that the numbers are low as possible. "-yne" is also used as a suffix to name substituent groups that are triply bound to the parent compound. + +Sometimes a number between hyphens is inserted before it to state which atoms the triple bond is between. This suffix arose as a collapsed form of the end of the word "acetylene". The final "-e" disappears if it is followed by another suffix that starts with a vowel. + +Structural isomerism +Alkynes having four or more carbon atoms can form different structural isomers by having the triple bond in different positions or having some of the carbon atoms be substituents rather than part of the parent chain. Other non-alkyne structural isomers are also possible. + : acetylene only + : propyne only + : 2 isomers: 1-butyne, and 2-butyne + : 3 isomers: 1-pentyne, 2-pentyne, and 3-methyl-butyne + : 7 isomers: 1-hexyne, 2-hexyne, 3-hexyne, 4-methyl-1-pentyne, 4-methyl-2-pentyne, 3-methyl-1-pentyne, 3,3-dimethyl-1-butyne + +Synthesis + +Cracking +Commercially, the dominant alkyne is acetylene itself, which is used as a fuel and a precursor to other compounds, e.g., acrylates. Hundreds of millions of kilograms are produced annually by partial oxidation of natural gas: + 2 CH4 + 3/2 O2 -> HC#CH + 3 H2O +Propyne, also industrially useful, is also prepared by thermal cracking of hydrocarbons. + +Dehydrohalogenation and related reactions +Alkynes are prepared from 1,2- and 1,1-alkyl dihalides by double dehydrohalogenation. The reaction provides a means to generate alkynes from alkenes, which are first halogenated and then dehydrohalogenated. For example, phenylacetylene can be generated from styrene by bromination followed by treatment of the resulting of styrene dibromide with sodium amide in ammonia: + +Via the Fritsch–Buttenberg–Wiechell rearrangement, alkynes are prepared from vinyl bromides. Alkynes can be prepared from aldehydes using the Corey–Fuchs reaction and from aldehydes or ketones by the Seyferth–Gilbert homologation. + +Vinyl chlorides are susceptible to dehydrochlorination. Vinyl chlorides are available from aldehydes using the reagent (chloromethylene)triphenylphosphorane. + +Reactions, including applications +Featuring a reactive functional group, alkynes participate in many organic reactions. Such use was pioneered by Ralph Raphael, who in 1955 wrote the first book describing their versatility as intermediates in synthesis. + +Hydrogenation +Being more unsaturated than alkenes, alkynes characteristically undergo reactions that show that they are "doubly unsaturated". Alkynes are capable of adding two equivalents of , whereas an alkene adds only one equivalent. Depending on catalysts and conditions, alkynes add one or two equivalents of hydrogen. Partial hydrogenation, stopping after the addition of only one equivalent to give the alkene, is usually more desirable since alkanes are less useful: + +The largest scale application of this technology is the conversion of acetylene to ethylene in refineries (the steam cracking of alkanes yields a few percent acetylene, which is selectively hydrogenated in the presence of a palladium/silver catalyst). For more complex alkynes, the Lindlar catalyst is widely recommended to avoid formation of the alkane, for example in the conversion of phenylacetylene to styrene. Similarly, halogenation of alkynes gives the alkene dihalides or alkyl tetrahalides: + +RCH=CR'H + H2 -> RCH2CR'H2 + +The addition of one equivalent of to internal alkynes gives cis-alkenes. + +Addition of halogens and related reagents +Alkynes characteristically are capable of adding two equivalents of halogens and hydrogen halides. +RC#CR' + 2 Br2 -> RCBr2CR'Br2 + +The addition of nonpolar bonds across is general for silanes, boranes, and related hydrides. The hydroboration of alkynes gives vinylic boranes which oxidize to the corresponding aldehyde or ketone. In the thiol-yne reaction the substrate is a thiol. + +Addition of hydrogen halides has long been of interest. In the presence of mercuric chloride as a catalyst, acetylene and hydrogen chloride react to give vinyl chloride. While this method has been abandoned in the West, it remains the main production method in China. + +Hydration +The hydration reaction of acetylene gives acetaldehyde. The reaction proceeds by formation of vinyl alcohol, which undergoes tautomerizes to form the aldehyde. This reaction was once a major industrial process but it has been displaced by the Wacker process. This reaction occurs in nature, the catalyst being acetylene hydratase. + +The hydration of phenylacetylene gives acetophenone, and the catalyzed hydration of 1,8-nonadiyne to 2,8-nonanedione: +PhC#CH + H2O -> PhCOCH3 +HC#C(CH2)5C#CH + 2H2O -> CH3CO(CH2)5COCH3 + +Tautomerism +Terminal alkyl alkynes exhibit tautomerism. Propyne exists in equilibrium with propadiene: +HC#C-CH3 <=> CH2=C=CH2 + +Cycloadditions and oxidation +Alkynes undergo diverse cycloaddition reactions. The Diels–Alder reaction with 1,3-dienes give 1,4-cyclohexadienes. This general reaction has been extensively developed. Electrophilic alkynes are especially effective dienophiles. The "cycloadduct" derived from the addition of alkynes to 2-pyrone eliminates carbon dioxide to give the aromatic compound. Other specialized cycloadditions include multicomponent reactions such as alkyne trimerisation to give aromatic compounds and the [2+2+1]-cycloaddition of an alkyne, alkene and carbon monoxide in the Pauson–Khand reaction. Non-carbon reagents also undergo cyclization, e.g. Azide alkyne Huisgen cycloaddition to give triazoles. Cycloaddition processes involving alkynes are often catalyzed by metals, e.g. enyne metathesis and alkyne metathesis, which allows the scrambling of carbyne (RC) centers: +RC#CR + R'C#CR' <=> 2RC#CR' +Oxidative cleavage of alkynes proceeds via cycloaddition to metal oxides. Most famously, potassium permanganate converts alkynes to a pair of carboxylic acids. + +Reactions specific for terminal alkynes +Terminal alkynes are readily converted to many derivatives, e.g. by coupling reactions and condensations. Via the condensation with formaldehyde and acetylene is produced butynediol: +2CH2O + HC#CH -> HOCH2CCCH2OH + +In the Sonogashira reaction, terminal alkynes are coupled with aryl or vinyl halides: + +This reactivity exploits the fact that terminal alkynes are weak acids, whose typical pKa values around 25 place them between that of ammonia (35) and ethanol (16): +RC#CH + MX -> RC#CM + HX +where MX = NaNH2, LiBu, or RMgX. + +The reactions of alkynes with certain metal cations, e.g. and also gives acetylides. Thus, few drops of diamminesilver(I) hydroxide () reacts with terminal alkynes signaled by formation of a white precipitate of the silver acetylide. This reactivity is the basis of alkyne coupling reactions, including the Cadiot–Chodkiewicz coupling, Glaser coupling, and the Eglinton coupling: + +2R-\!{\equiv}\!-H ->[\ce{Cu(OAc)2}][\ce{pyridine}] R-\!{\equiv}\!-\!{\equiv}\!-R + +In the Favorskii reaction and in alkynylations in general, terminal alkynes add to carbonyl compounds to give the hydroxyalkyne. + +Metal complexes + +Alkynes form complexes with transition metals. Such complexes occur also in metal catalyzed reactions of alkynes such as alkyne trimerization. Terminal alkynes, including acetylene itself, react with water to give aldehydes. The transformation typically requires metal catalysts to give this anti-Markovnikov addition result. + +Alkynes in nature and medicine +According to Ferdinand Bohlmann, the first naturally occurring acetylenic compound, dehydromatricaria ester, was isolated from an Artemisia species in 1826. In the nearly two centuries that have followed, well over a thousand naturally occurring acetylenes have been discovered and reported. Polyynes, a subset of this class of natural products, have been isolated from a wide variety of plant species, cultures of higher fungi, bacteria, marine sponges, and corals. Some acids like tariric acid contain an alkyne group. Diynes and triynes, species with the linkage RC≡C–C≡CR′ and RC≡C–C≡C–C≡CR′ respectively, occur in certain plants (Ichthyothere, Chrysanthemum, Cicuta, Oenanthe and other members of the Asteraceae and Apiaceae families). Some examples are cicutoxin, oenanthotoxin, and falcarinol . These compounds are highly bioactive, e.g. as nematocides. 1-Phenylhepta-1,3,5-triyne is illustrative of a naturally occurring triyne. + +Alkynes occur in some pharmaceuticals, including the contraceptive noretynodrel. A carbon–carbon triple bond is also present in marketed drugs such as the antiretroviral Efavirenz and the antifungal Terbinafine. Molecules called ene-diynes feature a ring containing an alkene ("ene") between two alkyne groups ("diyne"). These compounds, e.g. calicheamicin, are some of the most aggressive antitumor drugs known, so much so that the ene-diyne subunit is sometimes referred to as a "warhead". Ene-diynes undergo rearrangement via the Bergman cyclization, generating highly reactive radical intermediates that attack DNA within the tumor. + +See also + + -yne + cycloalkyne + +References +AbiWord () is a free and open-source software word processor. It is written in C++ and since version 3 it is based on GTK+ 3. The name "AbiWord" is derived from the root of the Spanish word "abierto", meaning "open". + +AbiWord was originally started by SourceGear Corporation as the first part of a proposed AbiSuite but was adopted by open source developers after SourceGear changed its business focus and ceased development. It now runs on Linux, ReactOS, Solaris, AmigaOS 4.0 (through its Cygwin X11 engine), MeeGo (on the Nokia N9 smartphone), Maemo (on the Nokia N810), QNX and other operating systems. Development of a version for Microsoft Windows has temporarily ended due to lack of maintainers (the latest released versions are 2.8.6 and 2.9.4 beta). + +The macOS port has remained on version 2.4 since 2005, although the current version does run non-natively on macOS through XQuartz. + +AbiWord is part of the AbiSource project which develops a number of office-related technologies. Abiword is one of the rare text processing software which allows local users to edit simultaneously the same shared document in a local network, without the requirement of an Internet connection, since 2009. + +Features +AbiWord supports both basic word processing features such as lists, indents and character formats, and more sophisticated features including tables, styles, page headers and footers, footnotes, templates, multiple views, page columns, spell checking, and grammar checking. Starting with version 2.8.0, AbiWord includes a collaboration plugin that allows integration with AbiCollab.net, a Web-based service that permits multiple users to work on the same document in real time, in full synchronization. The Presentation view of AbiWord, which permits easy display of presentations created in AbiWord on "screen-sized" pages, is another feature not often found in word processors. + +Interface +AbiWord generally works similarly to classic versions (pre-Office 2007) of Microsoft Word, as direct ease of migration was a high priority early goal. While many interface similarities remain, cloning the Word interface is no longer a top priority. The interface is intended to follow user interface guidelines for each respective platform. + +File formats +AbiWord comes with several import and export filters providing partial support for such formats as HTML, Microsoft Word (.doc), Office Open XML (.docx), OpenDocument Text (.odt), Rich Text Format (.rtf), and text documents (.txt). LaTeX is supported for export only. Plug-in filters are available to deal with many other formats, notably WordPerfect documents. The native file format, .abw, uses XML, so as to mitigate vendor lock-in concerns with respect to interoperability and digital archiving. + +Grammar checking +The AbiWord project includes a US English-only grammar checking plugin using Link Grammar. AbiWord had grammar checking before any other open source word processor, although a grammar checker was later added to OpenOffice.org. Link Grammar is both a theory of syntax and an open source parser which is now developed by the AbiWord project. + +See also + +List of free and open-source software packages +List of word processors + Comparison of word processors + Office Open XML software + OpenDocument software + +References + +External links + + + + + + + +1998 software +Cross-platform free software +Free software programmed in C++ +Free word processors +Linux word processors +MacOS word processors +Office software that uses GTK +Portable software +Software using the GPL license +Windows word processors +The Ames test is a widely employed method that uses bacteria to test whether a given chemical can cause mutations in the DNA of the test organism. More formally, it is a biological assay to assess the mutagenic potential of chemical compounds. A positive test indicates that the chemical is mutagenic and therefore may act as a carcinogen, because cancer is often linked to mutation. The test serves as a quick and convenient assay to estimate the carcinogenic potential of a compound because standard carcinogen assays on mice and rats are time-consuming (taking two to three years to complete) and expensive. However, false-positives and false-negatives are known. + +The procedure was described in a series of papers in the early 1970s by Bruce Ames and his group at the University of California, Berkeley. + +General procedure +The Ames test uses several strains of the bacterium Salmonella typhimurium that carry mutations in genes involved in histidine synthesis. These strains are auxotrophic mutants, i.e. they require histidine for growth, but cannot produce it. The method tests the capability of the tested substance in creating mutations that result in a return to a "prototrophic" state, so that the cells can grow on a histidine-free medium. + +The tester strains are specially constructed to detect either frameshift (e.g. strains TA-1537 and TA-1538) or point (e.g. strain TA-1531) mutations in the genes required to synthesize histidine, so that mutagens acting via different mechanisms may be identified. Some compounds are quite specific, causing reversions in just one or two strains. The tester strains also carry mutations in the genes responsible for lipopolysaccharide synthesis, making the cell wall of the bacteria more permeable, and in the excision repair system to make the test more sensitive. + +Larger organisms like mammals have metabolic processes that could potentially turn a chemical considered not mutagenic into one that is or one that is considered mutagenic into one that is not. Therefore, to more effectively test a chemical compound's mutagenicity in relation to larger organisms, rat liver enzymes can be added in an attempt to replicate the metabolic processes' effect on the compound being tested in the Ames Test. Rat liver extract is optionally added to simulate the effect of metabolism, as some compounds, like benzo[a]pyrene, are not mutagenic themselves but their metabolic products are. + +The bacteria are spread on an agar plate with small amount of histidine. This small amount of histidine in the growth medium allows the bacteria to grow for an initial time and have the opportunity to mutate. +When the histidine is depleted only bacteria that have mutated to gain the ability to produce its own histidine will survive. The plate is incubated for 48 hours. The mutagenicity of a substance is proportional to the number of colonies observed. + +Ames test and carcinogens +Mutagens identified via Ames test are also possible carcinogens, and early studies by Ames showed that 90% of known carcinogens may be identified via this test. Later studies however showed identification of 50–70% of known carcinogens. The test was used to identify a number of compounds previously used in commercial products as potential carcinogens. Examples include tris(2,3-dibromopropyl)phosphate, which was used as a flame retardant in plastic and textiles such as children's sleepwear, and furylfuramide which was used as an antibacterial additive in food in Japan in the 1960s and 1970s. Furylfuramide in fact had previously passed animal tests, but more vigorous tests after its identification in the Ames test showed it to be carcinogenic. Their positive tests resulted in those chemicals being withdrawn from use in consumer products. + +One interesting result from the Ames test is that the dose response curve using varying concentrations of the chemical is almost always linear, indicating that there is no threshold concentration for mutagenesis. It therefore suggests that, as with radiation, there may be no safe threshold for chemical mutagens or carcinogens. However, some have proposed that organisms could tolerate low levels of mutagens due to protective mechanisms such as DNA repair, and thus a threshold may exist for certain chemical mutagens. Bruce Ames himself argued against linear dose-response extrapolation from the high dose used in carcinogenesis tests in animal systems to the lower dose of chemicals normally encountered in human exposure, as the results may be false positives due to mitogenic response caused by the artificially high dose of chemicals used in such tests. He also cautioned against the "hysteria over tiny traces of chemicals that may or may not cause cancer", that "completely drives out the major risks you should be aware of". + +The Ames test is often used as one of the initial screens for potential drugs to weed out possible carcinogens, and it is one of the eight tests required under the Pesticide Act (USA) and one of the six tests required under the Toxic Substances Control Act (USA). + +Limitations +Salmonella typhimurium is a prokaryote, therefore it is not a perfect model for humans. Rat liver S9 fraction is used to mimic the mammalian metabolic conditions so that the mutagenic potential of metabolites formed by a parent molecule in the hepatic system can be assessed; however, there are differences in metabolism between humans and rats that can affect the mutagenicity of the chemicals being tested. The test may therefore be improved by the use of human liver S9 fraction; its use was previously limited by its availability, but it is now available commercially and therefore may be more feasible. An adapted in vitro model has been made for eukaryotic cells, for example yeast. + +Mutagens identified in the Ames test need not necessarily be carcinogenic, and further tests are required for any potential carcinogen identified in the test. Drugs that contain the nitrate moiety sometimes come back positive for Ames when they are indeed safe. The nitrate compounds may generate nitric oxide, an important signal molecule that can give a false positive. Nitroglycerin is an example that gives a positive Ames yet is still used in treatment today. Nitrates in food however may be reduced by bacterial action to nitrites which are known to generate carcinogens by reacting with amines and amides. Long toxicology and outcome studies are needed with such compounds to disprove a positive Ames test. + +Fluctuation method + +The Ames test was initially developed using agar plates (the plate incorporation technique), as described above. Since that time, an alternative to performing the Ames test has been developed, which is known as the "fluctuation method". This technique is the same in concept as the agar-based method, with bacteria being added to a reaction mixture with a small amount of histidine, which allows the bacteria to grow and mutate, returning to synthesize their own histidine. By including a pH indicator, the frequency of mutation is counted in microplates as the number of wells which have changed color (caused by a drop in pH due to metabolic processes of reproducing bacteria). As with the traditional Ames test, the sample is compared to the natural background rate of reverse mutation in order to establish the genotoxicity of a substance. The fluctuation method is performed entirely in liquid culture and is scored by counting the number of wells that turn yellow from purple in 96-well or 384-well microplates. + +In the 96-well plate method the frequency of mutation is counted as the number of wells out of 96 which have changed color. The plates are incubated for up to five days, with mutated (yellow) colonies being counted each day and compared to the background rate of reverse mutation using established tables of significance to determine the significant differences between the background rate of mutation and that for the tested samples. + +In the more scaled-down 384-well plate microfluctuation method the frequency of mutation is counted as the number of wells out of 48 which have changed color after 2 days of incubation. A test sample is assayed across 6 dose levels with concurrent zero-dose (background) and positive controls which all fit into one 384-well plate. The assay is performed in triplicates to provide statistical robustness. It uses the recommended OECD Guideline 471 tester strains (histidine auxotrophs and tryptophan auxotrophs). + +The fluctuation method is comparable to the traditional pour plate method in terms of sensitivity and accuracy, however, it does have a number of advantages: it needs less test sample, it has a simple colorimetric endpoint, counting the number of positive wells out of possible 96 or 48 wells is much less time-consuming than counting individual colonies on an agar plate. Several commercial kits are available. Most kits have consumable components in a ready-to-use state, including lyophilized bacteria, and tests can be performed using multichannel pipettes. The fluctuation method also allows for testing higher volumes of aqueous samples (up to 75% v/v), increasing the sensitivity and extending its application to low-level environmental mutagens. + +References + +Further reading + + + +Applied genetics +Biochemistry detection reactions +Laboratory techniques +Toxicology tests +Angiotensin-converting-enzyme inhibitors (ACE inhibitors) are a class of medication used primarily for the treatment of high blood pressure and heart failure. This class of medicine works by causing relaxation of blood vessels as well as a decrease in blood volume, which leads to lower blood pressure and decreased oxygen demand from the heart. + +ACE inhibitors inhibit the activity of angiotensin-converting enzyme, an important component of the renin–angiotensin system which converts angiotensin I to angiotensin II, and hydrolyses bradykinin. Therefore, ACE inhibitors decrease the formation of angiotensin II, a vasoconstrictor, and increase the level of bradykinin, a peptide vasodilator. This combination is synergistic in lowering blood pressure. As a result of inhibiting the ACE enzyme in the bradykinin system, the ACE inhibitor drugs allow for increased levels of bradykinin which would normally be degraded. Bradykinin produces prostaglandin. This mechanism can explain the two most common side effects seen with ACE Inhibitors: angioedema and cough. + +Frequently prescribed ACE inhibitors include benazepril, zofenopril, perindopril, trandolapril, captopril, enalapril, lisinopril, and ramipril. + +Medical use +ACE inhibitors were initially approved for the treatment of hypertension and can be used alone or in combination with other anti-hypertensive medications. Later, they were found useful for other cardiovascular and kidney diseases including: + Acute myocardial infarction (heart attack) + Heart failure (left ventricular systolic dysfunction) + Kidney complications of diabetes mellitus (diabetic nephropathy) by means of decreasing the blood pressure and increasing perfusion in glomerular arterioles. + +In treating high blood pressure, ACE inhibitors are often the first drug choice, particularly when diabetes is present, but age can lead to different choices and it is common to need more than one drug to obtain the desired improvement. There are fixed-dose combination drugs, such as ACE inhibitor and thiazide combinations. ACE inhibitors have also been used in chronic kidney failure and kidney involvement in systemic sclerosis (hardening of tissues, as scleroderma renal crisis). In those with stable coronary artery disease, but no heart failure, benefits are similar to other usual treatments. + +In 2012, there was a meta-analysis published in the BMJ that described the protective role of ACE inhibitors in reducing the risk of pneumonia when compared to angiotensin II receptor blocker (ARBs). The authors found a decreased risk in patients with previous stroke (54% risk reduction), with heart failure (37% risk reduction), and of Asian descent (43% risk reduction vs 54% risk reduction in non-Asian population). However, no reduced pneumonia related mortality was observed. + +Other +ACE inhibitors may also be used to help decrease excessive water consumption in people with schizophrenia resulting in psychogenic polydipsia. A double-blind, placebo-controlled trial showed that when used for this purpose, enalapril led to decreased consumption (determined by urine output and osmolality) in 60% of people; the same effect has been demonstrated in other ACE inhibitors. + +Additionally ACE-I are commonly used after renal transplant to manage post-transplant erythrocytosis, a condition characterised by a persistently high hematocrit greater than 51% which often develops 8–24 months after successful transplantation, as ACE-I have been shown to decrease erythropoietin production. + +Adverse effects +Common side effects include: low blood pressure, cough, hyperkalemia, headache, dizziness, fatigue, nausea, and kidney impairment. + +The main adverse effects of ACE inhibition can be understood from their pharmacological action. The other reported adverse effects are liver problems and effects on the fetus. Kidney problems may occur with all ACE inhibitors that directly follows from their mechanism of action. Patients starting on an ACE inhibitor usually have a modest reduction in glomerular filtration rate (GFR). However, the decrease may be significant in conditions of pre-existing decreased renal perfusions, such as renal artery stenosis, heart failure, polycystic kidney disease, or volume depletion. In these patients, the maintenance of GFR depends on angiotensin-II-dependent efferent vasomotor tone. Therefore, renal function should be closely monitored over the first few days after initiation of treatment with ACE inhibitor in patients with decreased renal perfusion. A moderate reduction in renal function, no greater than 30% rise in serum creatinine, that is stabilized after a week of treatment is deemed acceptable as part of the therapeutic effect, providing the residual renal function is sufficient. + +Reduced GFR is especially a problem if the patient is concomitantly taking an NSAID and a diuretic. When the three drugs are taken together, the risk of developing renal failure is significantly increased. + +High blood potassium is another possible complication of treatment with an ACE inhibitor due to its effect on aldosterone. Suppression of angiotensin II leads to a decrease in aldosterone levels. Since aldosterone is responsible for increasing the excretion of potassium, ACE inhibitors can cause retention of potassium. Some people, however, can continue to lose potassium while on an ACE inhibitor. Hyperkalemia may decrease the velocity of impulse conduction in the nerves and muscles, including cardiac tissues. This leads to cardiac dysfunction and neuromuscular consequences, such as muscle weakness, paresthesia, nausea, diarrhea, and others. Close monitoring of potassium levels is required in patients receiving treatment with ACE inhibitors who are at risk of hyperkalemia. + +Another possible adverse effect specific for ACE inhibitors, but not for other RAAS blockers, is an increase in bradykinin level. + +A persistent dry cough is a relatively common adverse effect believed to be associated with the increases in bradykinin levels produced by ACE inhibitors, although the role of bradykinin in producing these symptoms has been disputed. Many cases of cough in people on ACE inhibitors may not be from the medication itself, however. People who experience this cough are often switched to angiotensin II receptor antagonists. + +Some (0.7%) develop angioedema due to increased bradykinin levels. A genetic predisposition may exist. + +A severe rare allergic reaction can affect the bowel wall and secondarily cause abdominal pain. + +Blood +Hematologic effects, such as neutropenia, agranulocytosis and other blood dyscrasias, have occurred during therapy with ACE inhibitors, especially in people with additional risk factors. + +Pregnancy +In pregnant women, ACE inhibitors taken during all the trimesters have been reported to cause congenital malformations, stillbirths, and neonatal deaths. Commonly reported fetal abnormalities include hypotension, renal dysplasia, anuria/oliguria, oligohydramnios, intrauterine growth retardation, pulmonary hypoplasia, patent ductus arteriosus, and incomplete ossification of the skull. Overall, about half of newborns exposed to ACE inhibitors are adversely affected, leading to birth defects. + +ACE inhibitors are ADEC pregnancy category D and should be avoided in women who are likely to become pregnant. In the U.S., ACE inhibitors must be labeled with a boxed warning concerning the risk of birth defects when taken during the second and third trimester. Their use in the first trimester is also associated with a risk of major congenital malformations, particularly affecting the cardiovascular and central nervous systems. + +Overdose +Symptoms and Treatment: There are few reports of ACE inhibitor overdose in the literature. The most likely manifestations are hypotension, which may be severe, hyperkalemia, hyponatremia and renal impairment with metabolic acidosis. Treatment should be mainly symptomatic and supportive, with volume expansion using normal saline to correct hypotension and improve renal function, and gastric lavage followed by activated charcoal and a cathartic to prevent further absorption of the drug. Captopril, enalapril, lisinopril and perindopril are known to be removable by hemodialysis. + +Contraindications and precautions +The ACE inhibitors are contraindicated in people with: + Pregnancy or breastfeeding + Previous angioedema associated with ACE inhibitor therapy + Bilateral renal artery stenosis + Hypersensitivity to ACE inhibitors + +ACE inhibitors should be used with caution in people with: + Impaired renal function + Aortic valve stenosis or cardiac outflow obstruction + Hypovolemia or dehydration + Hemodialysis with high-flux polyacrylonitrile membranes + +A combination of ACE inhibitor with other drugs may increase effects of these drugs, but also the risk of adverse effects. The commonly reported adverse effects of drug combination with ACE inhibitor are acute renal failure, hypotension, and hyperkalemia. The drugs interacting with ACE inhibitor should be prescribed with caution. Special attention should be given to combinations of ACE inhibitor with other RAAS blockers, diuretics (especially potassium-sparing diuretics), NSAIDs, anticoagulants, cyclosporine, DPP-4 inhibitors, and potassium supplements. + +Potassium supplementation should be used with caution and under medical supervision owing to the hyperkalemic effect of ACE inhibitors. + +Concomitant use with cyclooxygenase inhibitors tends to decrease ACE inhibitor's hypotensive effect. + +Mechanism of action +ACE inhibitors reduce the activity of the renin–angiotensin–aldosterone system (RAAS) as the primary etiologic (causal) event in the development of hypertension in people with diabetes mellitus, as part of the insulin-resistance syndrome or as a manifestation of renal disease. + +Renin–angiotensin–aldosterone system + +The renin–angiotensin–aldosterone system is a major blood pressure regulating mechanism. Markers of electrolyte and water imbalance in the body such as hypotension, low distal tubule sodium concentration, decreased blood volume and high sympathetic tone trigger the release of the enzyme renin from the cells of juxtaglomerular apparatus in the kidney. + +Renin activates a circulating liver derived prohormone angiotensinogen by proteolytic cleavage of all but its first ten amino acid residues known as angiotensin I. ACE (angiotensin converting enzyme) then removes a further two residues, converting angiotensin I into angiotensin II. ACE is found in the pulmonary circulation and in the endothelium of many blood vessels. The system increases blood pressure by increasing the amount of salt and water the body retains, although angiotensin is also very good at causing the blood vessels to tighten (a potent vasoconstrictor). + +Effects +ACE inhibitors block the conversion of angiotensin I (ATI) to angiotensin II (ATII). They thereby lower arteriolar resistance and increase venous capacity; decrease cardiac output, cardiac index, stroke work, and volume; lower resistance in blood vessels in the kidneys; and lead to increased natriuresis (excretion of sodium in the urine). Renin increases in concentration in the blood as a result of negative feedback of conversion of ATI to ATII. ATI increases for the same reason; ATII and aldosterone decrease. Bradykinin increases because of less inactivation by ACE. + +Under normal conditions, angiotensin II has these effects: + Vasoconstriction (narrowing of blood vessels) and vascular smooth muscle hypertrophy (enlargement) induced by ATII may lead to increased blood pressure and hypertension. Further, constriction of the efferent arterioles of the kidney leads to increased perfusion pressure in the glomeruli. + It contributes to ventricular remodeling and ventricular hypertrophy of the heart through stimulation of the proto-oncogenes c-fos, c-jun, c-myc, transforming growth factor beta (TGF-B), through fibrogenesis and apoptosis (programmed cell death). + Stimulation by ATII of the adrenal cortex to release aldosterone, a hormone that acts on kidney tubules, causes sodium and chloride ions retention and potassium excretion. Sodium is a "water-holding" ion, so water is also retained, which leads to increased blood volume, hence an increase in blood pressure. + Stimulation of the posterior pituitary to release vasopressin (antidiuretic hormone, ADH) also acts on the kidneys to increase water retention. If ADH production is excessive in heart failure, Na+ level in the plasma may fall (hyponatremia), and this is a sign of increased risk of death in heart failure patients. + A decrease renal protein kinase C + +During the course of ACE inhibitor use, the production of ATII is decreased, which prevents aldosterone release from the adrenal cortex. This allows the kidney to excrete sodium ions along with obligate water, and retain potassium ions. This decreases blood volume, leading to decreased blood pressure. + +Epidemiological and clinical studies have shown ACE inhibitors reduce the progress of diabetic nephropathy independently from their blood pressure-lowering effect. This action of ACE inhibitors is used in the prevention of diabetic renal failure. + +ACE inhibitors have been shown to be effective for indications other than hypertension even in patients with normal blood pressure. The use of a maximum dose of ACE inhibitors in such patients (including for prevention of diabetic nephropathy, congestive heart failure, and prophylaxis of cardiovascular events) is justified, because it improves clinical outcomes independently of the blood pressure-lowering effect of ACE inhibitors. Such therapy, of course, requires careful and gradual titration of the dose to prevent the effects of rapidly decreasing blood pressure (dizziness, fainting, etc.). + +ACE inhibitors have also been shown to cause a central enhancement of parasympathetic nervous system activity in healthy volunteers and patients with heart failure. This action may reduce the prevalence of malignant cardiac arrhythmias, and the reduction in sudden death reported in large clinical trials. +ACE Inhibitors also reduce plasma norepinephrine levels, and its resulting vasoconstriction effects, in heart failure patients, thus breaking the vicious circles of sympathetic and renin angiotensin system activation, which sustains the downward spiral in cardiac function in congestive heart failure + +The ACE inhibitor enalapril has also been shown to reduce cardiac cachexia in patients with chronic heart failure. Cachexia is a poor prognostic sign in patients with chronic heart failure. +ACE inhibitors are under early investigation for the treatment of frailty and muscle wasting (sarcopenia) in elderly patients without heart failure. + +Examples +Currently, there are 10 ACE inhibitors approved for use in the United States by the FDA: captopril (1981), enalapril (1985), lisinopril (1987), benazepril (1991), fosinopril (1991), quinapril (1991), ramipril (1991), perindopril (1993), moexipril (1995) and trandolapril (1996). + +ACE inhibitors are easily identifiable by their common suffix, '-pril'. ACE inhibitors can be divided into three groups based on their molecular structure of the enzyme binding sites (sulfhydryl, phosphinyl, carboxyl) to the active center of ACE: + +Sulfhydryl-containing agents + Alacepril + Captopril (trade name Capoten), the first ACE inhibitor. + Zofenopril + +These agents appear to show antioxidative properties but may be involved in adverse events such as skin eruptions. + +Dicarboxylate-containing agents +This is the largest group, including: + Enalapril (Vasotec/Renitec/Berlipril/Enap/Enalapril Profarma) + Ramipril (Altace/Prilace/Ramace/Ramiwin/Triatec/Tritace/Ramitac) + Quinapril (Accupril) + Perindopril (Coversyl/Aceon/Perindo) + Lisinopril (Listril/Lopril/Novatec/Prinivil/Zestril, Lisidigal) + Benazepril (Lotensin) + Imidapril (Tanatril) + Trandolapril (Mavik/Odrik/Gopten) + Cilazapril (Inhibace) + +Phosphonate-containing agents + Ceronapril (never marketed) + Fosinopril (Fositen/Monopril) + +Naturally occurring + A comprehensive resource on anti-hypertensive peptides is available in form of a database. It contains around 1700 unique antihypertensive peptides + Arfalasin (HOE 409) is angiotensin antagonist. + +Dairy products + Casokinins and lactokinins, breakdown products of casein and whey, occur naturally after ingestion of milk products, especially cultured milk. Their role in blood pressure control is uncertain. + The lactotripeptides Val-Pro-Pro and Ile-Pro-Pro produced by the probiotic Lactobacillus helveticus or derived from casein have been shown to have ACE-inhibiting and antihypertensive functions. In one study, L. helveticus PR4 was isolated from Italian cheeses. + +Comparative information +All ACE inhibitors have similar antihypertensive efficacy when equivalent doses are administered. The main differences lie with captopril, the first ACE inhibitor. Captopril has a shorter duration of action and an increased incidence of adverse effects. It is also the only ACE inhibitor capable of passing through the blood–brain barrier, although the significance of this characteristic has not been shown to have any positive clinical effects. + +In a large clinical study, one of the agents in the ACE inhibitor class, ramipril (Altace), demonstrated an ability to reduce the mortality rates of patients with a myocardial infarction and to slow the subsequent development of heart failure. This finding was made after it was discovered that regular use of ramipril reduced mortality rates even in test subjects who didn't have hypertension. + +Some believe ramipril's additional benefits may be shared by some or all drugs in the ACE-inhibitor class. However, ramipril currently remains the only ACE inhibitor for which such effects are actually evidence-based. + +A meta-analysis confirmed that ACE inhibitors are effective and certainly the first-line choice in hypertension treatment. This meta-analysis was based on 20 trials and a cohort of 158,998 patients, of whom 91% were hypertensive. ACE inhibitors were used as the active treatment in seven trials (n=76,615) and angiotensin receptor blocker (ARB) in 13 trials (n=82,383). +ACE inhibitors were associated with a statistically significant 10% mortality reduction: (HR 0.90; 95% CI, 0.84–0.97; P=0.004). In contrast, no significant mortality reduction was observed with ARB treatment (HR 0.99; 95% CI, 0.94–1.04; P=0.683). Analysis of mortality reduction by different ACE inhibitors showed that perindopril-based regimens are associated with a statistically significant 13% all-cause mortality reduction. +Taking into account the broad spectrum of the hypertensive population, one might expect that an effective treatment with ACE inhibitors, in particular with perindopril, would result in an important gain of lives saved. + +Equivalent doses in hypertension +The ACE inhibitors have different strengths with different starting dosages. Dosage should be adjusted according to the clinical response. + +Combination with angiotensin II receptor antagonists +ACE inhibitors possess many common characteristics with another class of cardiovascular drugs, angiotensin II receptor antagonists, which are often used when patients are intolerant of the adverse effects produced by ACE inhibitors. ACE inhibitors do not completely prevent the formation of angiotensin II, as blockage is dose-dependent, so angiotensin II receptor antagonists may be useful because they act to prevent the action of angiotensin II at the AT1 receptor, leaving AT2 receptor unblocked; the latter may have consequences needing further study. + +The combination therapy of angiotensin II receptor antagonists with ACE inhibitors may be superior to either agent alone. This combination may increase levels of bradykinin while blocking the generation of angiotensin II and its activity at the AT1 receptor. This 'dual blockade' may be more effective than using an ACE inhibitor alone, because angiotensin II can be generated via non-ACE-dependent pathways. Preliminary studies suggest this combination of pharmacologic agents may be advantageous in the treatment of essential hypertension, chronic heart failure, and nephropathy. However, the more recent ONTARGET study showed no benefit of combining the agents and more adverse events. While statistically significant results have been obtained for its role in treating hypertension, clinical significance may be lacking. There are warnings about the combination of ACE inhibitors with ARBs. + +Patients with heart failure may benefit from the combination in terms of reducing morbidity and ventricular remodeling. + +The most compelling evidence for the treatment of nephropathy has been found: This combination therapy partially reversed the proteinuria and also exhibited a renoprotective effect in patients with diabetic nephropathy, and pediatric IgA nephropathy. + +History + +Leonard T. Skeggs and his colleagues (including Norman Shumway) discovered ACE in plasma in 1956. It was also noted that those who worked in banana plantations in South-western Brazil collapsed after being bitten by a pit viper, leading to a search for a blood pressure lowering component in its venom. Brazilian scientist Sérgio Henrique Ferreira reported a bradykinin-potentiating factor (BPF) present in the venom of Bothrops jararaca, a South American pit viper, in 1965. Ferreira then went to John Vane's laboratory as a postdoctoral fellow with his already-isolated BPF. The conversion of the inactive angiotensin I to the potent angiotensin II was thought to take place in the plasma. However, in 1967, Kevin K. F. Ng and John R. Vane showed plasma ACE is too slow to account for the conversion of angiotensin I to angiotensin II in vivo. Subsequent investigation showed rapid conversion occurs during its passage through the pulmonary circulation. + +Bradykinin is rapidly inactivated in the circulating blood, and it disappears completely in a single pass through the pulmonary circulation. Angiotensin I also disappears in the pulmonary circulation because of its conversion to angiotensin II. Furthermore, angiotensin II passes through the lungs without any loss. The inactivation of bradykinin and the conversion of angiotensin I to angiotensin II in the lungs was thought to be caused by the same enzyme. In 1970, Ng and Vane, using BPF provided by Ferreira, showed the conversion is inhibited during its passage through the pulmonary circulation. + +BPFs are members of a family of peptides whose potentiating action is linked to inhibition of bradykinin by ACE. Molecular analysis of BPF yielded a nonapeptide BPF teprotide (SQ 20,881), which showed the greatest ACE inhibition potency and hypotensive effect in vivo. Teprotide had limited clinical value as a result of its peptide nature and lack of activity when given orally. In the early 1970s, knowledge of the structure-activity relationship required for inhibition of ACE was growing. David Cushman, Miguel Ondetti and colleagues used peptide analogues to study the structure of ACE, using carboxypeptidase A as a model. Their discoveries led to the development of captopril, the first orally-active ACE inhibitor, in 1975. + +Captopril was approved by the United States Food and Drug Administration in 1981. The first nonsulfhydryl-containing ACE inhibitor, enalapril, was approved four years later. At least 8 other ACE inhibitors have since been marketed. + +In 1991, Japanese scientists created the first milk-based ACE inhibitor, in the form of a fermented milk drink, using specific cultures to liberate the tripeptide isoleucine-proline-proline (IPP) from the dairy protein. Valine-proline-proline (VPP) is also liberated in this process—another milk tripeptide with a very similar chemical structure to IPP. Together, these peptides are now often referred to as lactotripeptides. In 1996, the first human study confirmed the blood pressure-lowering effect of IPP in fermented milk. Although twice the amount of VPP is needed to achieve the same ACE-inhibiting activity as the originally discovered IPP, VPP also is assumed to add to the total blood pressure lowering effect. +Since the first lactotripeptides discovery, more than 20 human clinical trials have been conducted in many different countries. + +Note + +See also + Angiotensin II receptor blocker + Discovery and development of angiotensin receptor blockers + Loop diuretic, also used to treat CHF + Renin inhibitor + +References + +External links + + From snake venom to ACE inhibitor — the discovery and rise of captopril + +ACE inhibitors +An antianginal is a drug used in the treatment of angina pectoris, a symptom of ischaemic heart disease. + +Examples +Drugs used are nitrates, beta blockers, or calcium channel blockers. + +Nitrates + +Nitrates cause vasodilation of the venous capacitance vessels by stimulating the endothelium-derived relaxing factor (EDRF). Used to relieve both exertional and vasospastic angina by allowing venous pooling, reducing the pressure in the ventricles and so reducing wall tension and oxygen requirements in, the heart. Short-acting nitrates are used to abort angina attacks that have occurred, while longer-acting nitrates are used in the prophylactic management of the condition. + +Agents include glyceryl trinitrate (GTN), pentaerythritol tetranitrate, isosorbide dinitrate and isosorbide mononitrate. + +Beta blockers +Beta blockers are used in the prophylaxis of exertional angina by reducing the myocardial oxygen demand below the level that would provoke an angina attack. + +They are contraindicated in variant angina and can precipitate heart failure. They are also contraindicated in severe asthmatics due to bronchoconstriction, and should be used cautiously in diabetics as they can mask symptoms of hypoglycemia. + +Agents include either cardioselectives such as acebutolol or metoprolol, or non-cardioselectives such as oxprenolol or sotalol. + +Calcium channel blockers +Calcium ion (Ca++) antagonists (Calcium channel blockers) are used in the treatment of chronic stable angina, and most effectively in the treatment of variant angina (directly preventing coronary artery vasospasm). They are not used in the treatment of unstable angina . + +In vitro, they dilate the coronary and peripheral arteries and have negative inotropic and chronotropic effects - decreasing afterload, improving myocardial efficiency, reducing heart rate and improving coronary blood flow. +In vivo, the vasodilation and hypotension trigger the baroreceptor reflex. Therefore, the net effect is the interplay of direct and reflex actions. + + Class I agents have the most potent negative inotropic effect and may cause heart failure. + Class II agents do not depress conduction or contractility. + Class III agent has negligible inotropic effect and causes almost no reflex tachycardia. + +Examples include Class I agents (e.g., verapamil), Class II agents (e.g., amlodipine, nifedipine), or the Class III agent diltiazem. + +Nifedipine is more a potent vasodilator and more effective in angina. It is in the class of dihydropyridines and does not affect refractory period on SA node conduction. + +References +The Anatomical Therapeutic Chemical (ATC) Classification System is a drug classification system that classifies the active ingredients of drugs according to the organ or system on which they act and their therapeutic, pharmacological and chemical properties. Its purpose is an aid to monitor drug use and for research to improve quality medication use. It does not imply drug recommendation or efficacy. It is controlled by the World Health Organization Collaborating Centre for Drug Statistics Methodology (WHOCC), and was first published in 1976. + +Coding system +This pharmaceutical coding system divides drugs into different groups according to the organ or system on which they act, their therapeutic intent or nature, and the drug's chemical characteristics. Different brands share the same code if they have the same active substance and indications. Each bottom-level ATC code stands for a pharmaceutically used substance, or a combination of substances, in a single indication (or use). This means that one drug can have more than one code, for example acetylsalicylic acid (aspirin) has as a drug for local oral treatment, as a platelet inhibitor, and as an analgesic and antipyretic; as well as one code can represent more than one active ingredient, for example is the combination of perindopril with amlodipine, two active ingredients that have their own codes ( and respectively) when prescribed alone. + +The ATC classification system is a strict hierarchy, meaning that each code necessarily has one and only one parent code, except for the 14 codes at the topmost level which have no parents. The codes are semantic identifiers, meaning they depict information by themselves beyond serving as identifiers (namely, the codes depict themselves the complete lineage of parenthood). As of 7 May 2020, there are 6,331 codes in ATC; the table below gives the count per level. + +History +The ATC system is based on the earlier Anatomical Classification System, which is intended as a tool for the pharmaceutical industry to classify pharmaceutical products (as opposed to their active ingredients). This system, confusingly also called ATC, was initiated in 1971 by the European Pharmaceutical Market Research Association (EphMRA) and is being maintained by the EphMRA and Intellus. Its codes are organised into four levels. The WHO's system, having five levels, is an extension and modification of the EphMRA's. It was first published in 1976. + +Classification +In this system, drugs are classified into groups at five different levels: + +First level +The first level of the code indicates the anatomical main group and consists of one letter. There are 14 main groups: + +Example: C Cardiovascular system + +Second level +The second level of the code indicates the therapeutic subgroup and consists of two digits. + +Example: C03 Diuretics + +Third level +The third level of the code indicates the therapeutic/pharmacological subgroup and consists of one letter. + +Example: C03C High-ceiling diuretics + +Fourth level +The fourth level of the code indicates the chemical/therapeutic/pharmacological subgroup and consists of one letter. + +Example: C03CA Sulfonamides + +Fifth level +The fifth level of the code indicates the chemical substance and consists of two digits. + +Example: C03CA01 furosemide + +Other ATC classification systems + +ATCvet +The Anatomical Therapeutic Chemical Classification System for veterinary medicinal products (ATCvet) is used to classify veterinary drugs. ATCvet codes can be created by placing the letter Q in front of the ATC code of most human medications. For example, furosemide for veterinary use has the code QC03CA01. + +Some codes are used exclusively for veterinary drugs, such as QI Immunologicals, QJ51 Antibacterials for intramammary use or QN05AX90 amperozide. + +Herbal ATC (HATC) +The Herbal ATC system (HATC) is an ATC classification of herbal substances; it differs from the regular ATC system by using 4 digits instead of 2 at the 5th level group. + +The herbal classification is not adopted by WHO. The Uppsala Monitoring Centre is responsible for the Herbal ATC classification, and it is part of the WHODrug Global portfolio available by subscription. + +Defined daily dose + +The ATC system also includes defined daily doses (DDDs) for many drugs. This is a measurement of drug consumption based on the usual daily dose for a given drug. According to the definition, "[t]he DDD is the assumed average maintenance dose per day for a drug used for its main indication in adults." + +Adaptations and updates +National issues of the ATC classification, such as the German Anatomisch-therapeutisch-chemische Klassifikation mit Tagesdosen, may include additional codes and DDDs not present in the WHO version. + +ATC follows guidelines in creating new codes for newly approved drugs. An application is submitted to WHO for ATC classification and DDD assignment. A preliminary or temporary code is assigned and published on the website and in the WHO Drug Information for comment or objection. New ATC/DDD codes are discussed at the semi-annual Working Group meeting. If accepted it becomes a final decision and published semi-annually on the website and WHO Drug Information and implemented in the annual print/on-line ACT/DDD Index on January 1. + +Changes to existing ATC/DDD follow a similar process to become temporary codes and if accepted become a final decision as ATC/DDD alterations. ATC and DDD alterations are only valid and implemented in the coming annual updates; the original codes must continue until the end of the year. + +An updated version of the complete on-line/print ATC index with DDDs is published annually on January 1. + +See also + Classification of Pharmaco-Therapeutic Referrals (CPR) + ICD-10 International Classification of Diseases + International Classification of Primary Care (ICPC-2) / ICPC-2 PLUS + Medical classification + Pharmaceutical care + Pharmacotherapy + RxNorm + +References + +External links + + Quarterly journal providing an overview of topics relating to medicines development and regulation. + from + EphMRA Anatomical Classification (ATC and NFC) + atcd. R script to scrape the ATC data from the WHOCC website; contains link to download entire ATC tree. + + + +Drugs +Pharmacological classification systems +World Health Organization +Parallel ATA (PATA), originally , also known as IDE, is a standard interface designed for IBM PC-compatible computers. It was first developed by Western Digital and Compaq in 1986 for compatible hard drives and CD or DVD drives. The connection is used for storage devices such as hard disk drives, floppy disk drives, and optical disc drives in computers. + +The standard is maintained by the X3/INCITS committee. It uses the underlying (ATA) and Packet Interface (ATAPI) standards. + +The Parallel ATA standard is the result of a long history of incremental technical development, which began with the original AT Attachment interface, developed for use in early PC AT equipment. The ATA interface itself evolved in several stages from Western Digital's original Integrated Drive Electronics (IDE) interface. As a result, many near-synonyms for ATA/ATAPI and its previous incarnations are still in common informal use, in particular Extended IDE (EIDE) and Ultra ATA (UATA). After the introduction of SATA in 2003, the original ATA was renamed to Parallel ATA, or PATA for short. + +Parallel ATA cables have a maximum allowable length of . Because of this limit, the technology normally appears as an internal computer storage interface. For many years, ATA provided the most common and the least expensive interface for this application. It has largely been replaced by SATA in newer systems. + +History and terminology +The standard was originally conceived as the "AT Bus Attachment," officially called "AT Attachment" and abbreviated "ATA" because its primary feature was a direct connection to the 16-bit ISA bus introduced with the IBM PC/AT. The original ATA specifications published by the standards committees use the name "AT Attachment". The "AT" in the IBM PC/AT referred to "Advanced Technology" so ATA has also been referred to as "Advanced Technology Attachment". When a newer Serial ATA (SATA) was introduced in 2003, the original ATA was renamed to Parallel ATA, or PATA for short. + +Physical ATA interfaces became a standard component in all PCs, initially on host bus adapters, sometimes on a sound card but ultimately as two physical interfaces embedded in a Southbridge chip on a motherboard. Called the "primary" and "secondary" ATA interfaces, they were assigned to base addresses 0x1F0 and 0x170 on ISA bus systems. They were replaced by SATA interfaces. + +IDE and ATA-1 + +The first version of what is now called the ATA/ATAPI interface was developed by Western Digital under the name Integrated Drive Electronics (IDE). Together with Compaq Computer (the initial customer), they worked with various disk drive manufacturers to develop and ship early products with the goal of remaining software compatible with the existing IBM PC hard drive interface. The first such drives appeared internally in Compaq PCs in 1986 + and were first separately offered by Conner Peripherals as the CP342 in June 1987. + +The term Integrated Drive Electronics refers to the fact that the drive controller is integrated into the drive, as opposed to a separate controller situated at the other side of the connection cable to the drive. On an IBM PC compatible, CP/M machine, or similar, this was typically a card installed on a motherboard. The interface cards used to connect a parallel ATA drive to, for example, an ISA Slot, are not drive controllers: they are merely bridges between the host bus and the ATA interface. Since the original ATA interface is essentially just a 16-bit ISA bus in disguise, the bridge was especially simple in case of an ATA connector being located on an ISA interface card. The integrated controller presented the drive to the host computer as an array of 512-byte blocks with a relatively simple command interface. This relieved the mainboard and interface cards in the host computer of the chores of stepping the disk head arm, moving the head arm in and out, and so on, as had to be done with earlier ST-506 and ESDI hard drives. All of these low-level details of the mechanical operation of the drive were now handled by the controller on the drive itself. This also eliminated the need to design a single controller that could handle many different types of drives, since the controller could be unique for the drive. The host need only to ask for a particular sector, or block, to be read or written, and either accept the data from the drive or send the data to it. + +The interface used by these drives was standardized in 1994 as ANSI standard X3.221-1994, AT Attachment Interface for Disk Drives. After later versions of the standard were developed, this became known as "ATA-1". + +A short-lived, seldom-used implementation of ATA was created for the IBM XT and similar machines that used the 8-bit version of the ISA bus. It has been referred to as "XT-IDE", "XTA" or "XT Attachment". + +EIDE and ATA-2 + +In 1994, about the same time that the ATA-1 standard was adopted, Western Digital introduced drives under a newer name, Enhanced IDE (EIDE). These included most of the features of the forthcoming ATA-2 specification and several additional enhancements. Other manufacturers introduced their own variations of ATA-1 such as "Fast ATA" and "Fast ATA-2". + +The new version of the ANSI standard, AT Attachment Interface with Extensions ATA-2 (X3.279-1996), was approved in 1996. It included most of the features of the manufacturer-specific variants. + +ATA-2 also was the first to note that devices other than hard drives could be attached to the interface: + +ATAPI + +As mentioned in the previous sections, ATA was originally designed for, and worked only with hard disk drives and devices that could emulate them. The introduction of ATAPI (ATA Packet Interface) by a group called the Small Form Factor committee (SFF) allowed ATA to be used for a variety of other devices that require functions beyond those necessary for hard disk drives. For example, any removable media device needs a "media eject" command, and a way for the host to determine whether the media is present, and these were not provided in the ATA protocol. + +The Small Form Factor committee approached this problem by defining ATAPI, the "ATA Packet Interface". ATAPI is actually a protocol allowing the ATA interface to carry SCSI commands and responses; therefore, all ATAPI devices are actually "speaking SCSI" other than at the electrical interface. In fact, some early ATAPI devices were simply SCSI devices with an ATA/ATAPI to SCSI protocol converter added on. The SCSI commands and responses are embedded in "packets" (hence "ATA Packet Interface") for transmission on the ATA cable. This allows any device class for which a SCSI command set has been defined to be interfaced via ATA/ATAPI. + +ATAPI devices are also "speaking ATA", as the ATA physical interface and protocol are still being used to send the packets. On the other hand, ATA hard drives and solid state drives do not use ATAPI. + +ATAPI devices include CD-ROM and DVD-ROM drives, tape drives, and large-capacity floppy drives such as the Zip drive and SuperDisk drive. + +The SCSI commands and responses used by each class of ATAPI device (CD-ROM, tape, etc.) are described in other documents or specifications specific to those device classes and are not within ATA/ATAPI or the T13 committee's purview. One commonly used set is defined in the MMC SCSI command set. + +ATAPI was adopted as part of ATA in INCITS 317-1998, AT Attachment with Packet Interface Extension (ATA/ATAPI-4). + +UDMA and ATA-4 + +The ATA/ATAPI-4 standard also introduced several "Ultra DMA" transfer modes. These initially supported speeds from 16 MByte/s to 33 MByte/second. In later versions, faster Ultra DMA modes were added, requiring new 80-wire cables to reduce crosstalk. The latest versions of Parallel ATA support up to 133 MByte/s. + +Ultra ATA +Ultra ATA, abbreviated UATA, is a designation that has been primarily used by Western Digital for different speed enhancements to the ATA/ATAPI standards. For example, in 2000 Western Digital published a document describing "Ultra ATA/100", which brought performance improvements for the then-current ATA/ATAPI-5 standard by improving maximum speed of the Parallel ATA interface from 66 to 100 MB/s. Most of Western Digital's changes, along with others, were included in the ATA/ATAPI-6 standard (2002). + +Current terminology +The terms "integrated drive electronics" (IDE), "enhanced IDE" and "EIDE" have come to be used interchangeably with ATA (now Parallel ATA, or PATA). + +In addition, there have been several generations of "EIDE" drives marketed, compliant with various versions of the ATA specification. An early "EIDE" drive might be compatible with ATA-2, while a later one with ATA-6. + +Nevertheless, a request for an "IDE" or "EIDE" drive from a computer parts vendor will almost always yield a drive that will work with most Parallel ATA interfaces. + +Another common usage is to refer to the specification version by the fastest mode supported. For example, ATA-4 supported Ultra DMA modes 0 through 2, the latter providing a maximum transfer rate of 33 megabytes per second. ATA-4 drives are thus sometimes called "UDMA-33" drives, and sometimes "ATA-33" drives. Similarly, ATA-6 introduced a maximum transfer speed of 100 megabytes per second, and some drives complying with this version of the standard are marketed as "PATA/100" drives. + +x86 BIOS size limitations + +Initially, the size of an ATA drive was stored in the system x86 BIOS using a type number (1 through 45) that predefined the C/H/S parameters and also often the landing zone, in which the drive heads are parked while not in use. Later, a "user definable" format called C/H/S or cylinders, heads, sectors was made available. These numbers were important for the earlier ST-506 interface, but were generally meaningless for ATA—the CHS parameters for later ATA large drives often specified impossibly high numbers of heads or sectors that did not actually define the internal physical layout of the drive at all. From the start, and up to ATA-2, every user had to specify explicitly how large every attached drive was. From ATA-2 on, an "identify drive" command was implemented that can be sent and which will return all drive parameters. + +Owing to a lack of foresight by motherboard manufacturers, the system BIOS was often hobbled by artificial C/H/S size limitations due to the manufacturer assuming certain values would never exceed a particular numerical maximum. + +The first of these BIOS limits occurred when ATA drives reached sizes in excess of 504 MiB, because some motherboard BIOSes would not allow C/H/S values above 1024 cylinders, 16 heads, and 63 sectors. Multiplied by 512 bytes per sector, this totals bytes which, divided by bytes per MiB, equals 504 MiB (528 MB). + +The second of these BIOS limitations occurred at 1024 cylinders, 256 heads, and 63 sectors, and a problem in MS-DOS limited the number of heads to 255. This totals to bytes (8032.5 MiB), commonly referred to as the 8.4 gigabyte barrier. This is again a limit imposed by x86 BIOSes, and not a limit imposed by the ATA interface. + +It was eventually determined that these size limitations could be overridden with a small program loaded at startup from a hard drive's boot sector. Some hard drive manufacturers, such as Western Digital, started including these override utilities with large hard drives to help overcome these problems. However, if the computer was booted in some other manner without loading the special utility, the invalid BIOS settings would be used and the drive could either be inaccessible or appear to the operating system to be damaged. + +Later, an extension to the x86 BIOS disk services called the "Enhanced Disk Drive" (EDD) was made available, which makes it possible to address drives as large as 264 sectors. + +Interface size limitations +The first drive interface used 22-bit addressing mode which resulted in a maximum drive capacity of two gigabytes. Later, the first formalized ATA specification used a 28-bit addressing mode through LBA28, allowing for the addressing of 228 () sectors (blocks) of 512 bytes each, resulting in a maximum capacity of 128 GiB (137 GB). + +ATA-6 introduced 48-bit addressing, increasing the limit to 128 PiB (144 PB). As a consequence, any ATA drive of capacity larger than about 137 GB must be an ATA-6 or later drive. Connecting such a drive to a host with an ATA-5 or earlier interface will limit the usable capacity to the maximum of the interface. + +Some operating systems, including Windows XP pre-SP1, and Windows 2000 pre-SP3, disable LBA48 by default, requiring the user to take extra steps to use the entire capacity of an ATA drive larger than about 137 gigabytes. + +Older operating systems, such as Windows 98, do not support 48-bit LBA at all. However, members of the third-party group MSFN have modified the Windows 98 disk drivers to add unofficial support for 48-bit LBA to Windows 95 OSR2, Windows 98, Windows 98 SE and Windows ME. + +Some 16-bit and 32-bit operating systems supporting LBA48 may still not support disks larger than 2 TiB due to using 32-bit arithmetic only; a limitation also applying to many boot sectors. + +Primacy and obsolescence +Parallel ATA (then simply called ATA or IDE) became the primary storage device interface for PCs soon after its introduction. In some systems, a third and fourth motherboard interface was provided, allowing up to eight ATA devices to be attached to the motherboard. Often, these additional connectors were implemented by inexpensive RAID controllers. + +Soon after the introduction of Serial ATA (SATA) in 2003, use of Parallel ATA declined. The first motherboards with built-in SATA interfaces usually had only a single PATA connector (for up to two PATA devices), along with multiple SATA connectors. Some PCs and laptops of the era have a SATA hard disk and an optical drive connected to PATA. + +As of 2007, some PC chipsets, for example the Intel ICH10, had removed support for PATA. Motherboard vendors still wishing to offer Parallel ATA with those chipsets must include an additional interface chip. In more recent computers, the Parallel ATA interface is rarely used even if present, as four or more Serial ATA connectors are usually provided on the motherboard and SATA devices of all types are common. + +With Western Digital's withdrawal from the PATA market, hard disk drives with the PATA interface were no longer in production after December 2013 for other than specialty applications. + +Parallel ATA interface + +Parallel ATA cables transfer data 16 bits at a time. The traditional cable uses 40-pin female connectors attached to a 40- or 80-conductor ribbon cable. Each cable has two or three connectors, one of which plugs into a host adapter interfacing with the rest of the computer system. The remaining connector(s) plug into storage devices, most commonly hard disk drives or optical drives. Each connector has 39 physical pins arranged into two rows (2.54 mm, -inch pitch), with a gap or key at pin 20. Earlier connectors may not have that gap, with all 40 pins available. Thus, later cables with the gap filled in are incompatible with earlier connectors, although earlier cables are compatible with later connectors. + +Round parallel ATA cables (as opposed to ribbon cables) were eventually made available for 'case modders' for cosmetic reasons, as well as claims of improved computer cooling and were easier to handle; however, only ribbon cables are supported by the ATA specifications. + + Pin 20 +In the ATA standard, pin 20 is defined as a mechanical key and is not used. This pin's socket on the female connector is often obstructed, requiring pin 20 to be omitted from the male cable or drive connector; it is thus impossible to plug it in the wrong way round. + +However, some flash memory drives can use pin 20 as VCC_in to power the drive without requiring a special power cable; this feature can only be used if the equipment supports this use of pin 20. + + Pin 28 +Pin 28 of the gray (slave/middle) connector of an 80-conductor cable is not attached to any conductor of the cable. It is attached normally on the black (master drive end) and blue (motherboard end) connectors. This enables cable select functionality. + + Pin 34 +Pin 34 is connected to ground inside the blue connector of an 80-conductor cable but not attached to any conductor of the cable, allowing for detection of such a cable. It is attached normally on the gray and black connectors. + +44-pin variant +A 44-pin variant PATA connector is used for 2.5 inch drives inside laptops. The pins are closer together (2.0 mm pitch) and the connector is physically smaller than the 40-pin connector. The extra pins carry power. + +80-conductor variant + +ATA's cables have had 40 conductors for most of its history (44 conductors for the smaller form-factor version used for 2.5" drives—the extra four for power), but an 80-conductor version appeared with the introduction of the UDMA/66 mode. All of the additional conductors in the new cable are grounds, interleaved with the signal conductors to reduce the effects of capacitive coupling between neighboring signal conductors, reducing crosstalk. Capacitive coupling is more of a problem at higher transfer rates, and this change was necessary to enable the 66 megabytes per second (MB/s) transfer rate of UDMA4 to work reliably. The faster UDMA5 and UDMA6 modes also require 80-conductor cables. + +Though the number of conductors doubled, the number of connector pins and the pinout remain the same as 40-conductor cables, and the external appearance of the connectors is identical. Internally, the connectors are different; the connectors for the 80-conductor cable connect a larger number of ground conductors to the ground pins, while the connectors for the 40-conductor cable connect ground conductors to ground pins one-to-one. 80-conductor cables usually come with three differently colored connectors (blue, black, and gray for controller, master drive, and slave drive respectively) as opposed to uniformly colored 40-conductor cable's connectors (commonly all gray). The gray connector on 80-conductor cables has pin 28 CSEL not connected, making it the slave position for drives configured cable select. + +Differences between connectors + +The image on the right shows PATA connectors after removal of strain relief, cover, and cable. Pin one is at bottom left of the connectors, pin 2 is top left, etc., except that the lower image of the blue connector shows the view from the opposite side, and pin one is at top right. + +The connector is an insulation-displacement connector: each contact comprises a pair of points which together pierce the insulation of the ribbon cable with such precision that they make a connection to the desired conductor without harming the insulation on the neighboring conductors. The center row of contacts are all connected to the common ground bus and attach to the odd numbered conductors of the cable. The top row of contacts are the even-numbered sockets of the connector (mating with the even-numbered pins of the receptacle) and attach to every other even-numbered conductor of the cable. The bottom row of contacts are the odd-numbered sockets of the connector (mating with the odd-numbered pins of the receptacle) and attach to the remaining even-numbered conductors of the cable. + +Note the connections to the common ground bus from sockets 2 (top left), 19 (center bottom row), 22, 24, 26, 30, and 40 on all connectors. Also note (enlarged detail, bottom, looking from the opposite side of the connector) that socket 34 of the blue connector does not contact any conductor but unlike socket 34 of the other two connectors, it does connect to the common ground bus. On the gray connector, note that socket 28 is completely missing, so that pin 28 of the drive attached to the gray connector will be open. On the black connector, sockets 28 and 34 are completely normal, so that pins 28 and 34 of the drive attached to the black connector will be connected to the cable. Pin 28 of the black drive reaches pin 28 of the host receptacle but not pin 28 of the gray drive, while pin 34 of the black drive reaches pin 34 of the gray drive but not pin 34 of the host. Instead, pin 34 of the host is grounded. + +The standard dictates color-coded connectors for easy identification by both installer and cable maker. All three connectors are different from one another. The blue (host) connector has the socket for pin 34 connected to ground inside the connector but not attached to any conductor of the cable. Since the old 40 conductor cables do not ground pin 34, the presence of a ground connection indicates that an 80 conductor cable is installed. The conductor for pin 34 is attached normally on the other types and is not grounded. Installing the cable backwards (with the black connector on the system board, the blue connector on the remote device and the gray connector on the center device) will ground pin 34 of the remote device and connect host pin 34 through to pin 34 of the center device. The gray center connector omits the connection to pin 28 but connects pin 34 normally, while the black end connector connects both pins 28 and 34 normally. + +Multiple devices on a cable +If two devices are attached to a single cable, one must be designated as Device 0 (in the past, commonly designated master) and the other as Device 1 (in the past, commonly designated as slave). This distinction is necessary to allow both drives to share the cable without conflict. The Device 0 drive is the drive that usually appears "first" to the computer's BIOS and/or operating system. In most personal computers the drives are often designated as "C:" for the Device 0 and "D:" for the Device 1 referring to one active primary partitions on each. + +The terms device and drive are used interchangeably in the industry, as in master drive or master device. + +The mode that a device must use is often set by a jumper setting on the device itself, which must be manually set to Device 0 (Master) or Device 1 (Slave). If there is a single device on a cable, it should be configured as Device 0. However, some certain era drives have a special setting called Single for this configuration (Western Digital, in particular). Also, depending on the hardware and software available, a Single drive on a cable will often work reliably even though configured as the Device 1 drive (most often seen where an optical drive is the only device on the secondary ATA interface). + +The words primary and secondary typically refers to the two IDE cables, which can have two drives each (primary master, primary slave, secondary master, secondary slave). + +Cable select + +A drive mode called cable select was described as optional in ATA-1 and has come into fairly widespread use with ATA-5 and later. A drive set to "cable select" automatically configures itself as Device 0 or Device 1, according to its position on the cable. Cable select is controlled by pin 28. The host adapter grounds this pin; if a device sees that the pin is grounded, it becomes the Device 0 (master) device; if it sees that pin 28 is open, the device becomes the Device 1 (slave) device. + +This setting is usually chosen by a jumper setting on the drive called "cable select", usually marked CS, which is separate from the Device 0/1 setting. + +Note that if two drives are configured as Device 0 and Device 1 manually, this configuration does not need to correspond to their position on the cable. Pin 28 is only used to let the drives know their position on the cable; it is not used by the host when communicating with the drives. In other words, the manual master/slave setting using jumpers on the drives takes precedence and allows them to be freely placed on either connector of the ribbon cable. + +With the 40-conductor cable, it was very common to implement cable select by simply cutting the pin 28 wire between the two device connectors; putting the slave Device 1 device at the end of the cable, and the master Device 0 on the middle connector. This arrangement eventually was standardized in later versions. However, it had one drawback: if there is just one master device on a 2-drive cable, using the middle connector, this results in an unused stub of cable, which is undesirable for physical convenience and electrical reasons. The stub causes signal reflections, particularly at higher transfer rates. + +Starting with the 80-conductor cable defined for use in ATAPI5/UDMA4, the master Device 0 device goes at the far-from-the-host end of the cable on the black connector, the slave Device 1 goes on the grey middle connector, and the blue connector goes to the host (e.g. motherboard IDE connector, or IDE card). So, if there is only one (Device 0) device on a two-drive cable, using the black connector, there is no cable stub to cause reflections (the unused connector is now in the middle of the ribbon). Also, cable select is now implemented in the grey middle device connector, usually simply by omitting the pin 28 contact from the connector body. + +Serialized, overlapped, and queued operations +The parallel ATA protocols up through ATA-3 require that once a command has been given on an ATA interface, it must complete before any subsequent command may be given. Operations on the devices must be serializedwith only one operation in progress at a timewith respect to the ATA host interface. A useful mental model is that the host ATA interface is busy with the first request for its entire duration, and therefore can not be told about another request until the first one is complete. The function of serializing requests to the interface is usually performed by a device driver in the host operating system. + +The ATA-4 and subsequent versions of the specification have included an "overlapped feature set" and a "queued feature set" as optional features, both being given the name "Tagged Command Queuing" (TCQ), a reference to a set of features from SCSI which the ATA version attempts to emulate. However, support for these is extremely rare in actual parallel ATA products and device drivers because these feature sets were implemented in such a way as to maintain software compatibility with its heritage as originally an extension of the ISA bus. This implementation resulted in excessive CPU utilization which largely negated the advantages of command queuing. By contrast, overlapped and queued operations have been common in other storage buses; in particular, SCSI's version of tagged command queuing had no need to be compatible with APIs designed for ISA, allowing it to attain high performance with low overhead on buses which supported first party DMA like PCI. This has long been seen as a major advantage of SCSI. + +The Serial ATA standard has supported native command queueing (NCQ) since its first release, but it is an optional feature for both host adapters and target devices. Many obsolete PC motherboards do not support NCQ, but modern SATA hard disk drives and SATA solid-state drives usually support NCQ, which is not the case for removable (CD/DVD) drives because the ATAPI command set used to control them prohibits queued operations. + +Two devices on one cable—speed impact +There are many debates about how much a slow device can impact the performance of a faster device on the same cable. There is an effect, but the debate is confused by the blurring of two quite different causes, called here "Lowest speed" and "One operation at a time". + +"Lowest speed" +On early ATA host adapters, both devices' data transfers can be constrained to the speed of the slower device, if two devices of different speed capabilities are on the same cable. + +For all modern ATA host adapters, this is not true, as modern ATA host adapters support independent device timing. This allows each device on the cable to transfer data at its own best speed. Even with earlier adapters without independent timing, this effect applies only to the data transfer phase of a read or write operation. + +"One operation at a time" +This is caused by the omission of both overlapped and queued feature sets from most parallel ATA products. Only one device on a cable can perform a read or write operation at one time; therefore, a fast device on the same cable as a slow device under heavy use will find it has to wait for the slow device to complete its task first. + +However, most modern devices will report write operations as complete once the data is stored in their onboard cache memory, before the data is written to the (slow) magnetic storage. This allows commands to be sent to the other device on the cable, reducing the impact of the "one operation at a time" limit. + +The impact of this on a system's performance depends on the application. For example, when copying data from an optical drive to a hard drive (such as during software installation), this effect probably will not matter. Such jobs are necessarily limited by the speed of the optical drive no matter where it is. But if the hard drive in question is also expected to provide good throughput for other tasks at the same time, it probably should not be on the same cable as the optical drive. + +HDD passwords and security + +ATA devices may support an optional security feature which is defined in an ATA specification, and thus not specific to any brand or device. The security feature can be enabled and disabled by sending special ATA commands to the drive. If a device is locked, it will refuse all access until it is unlocked. + +A device can have two passwords: A User Password and a Master Password; either or both may be set. There is a Master Password identifier feature which, if supported and used, can identify the current Master Password (without disclosing it). + +A device can be locked in two modes: High security mode or Maximum security mode. Bit 8 in word 128 of the IDENTIFY response shows which mode the disk is in: 0 = High, 1 = Maximum. + +In High security mode, the device can be unlocked with either the User or Master password, using the "SECURITY UNLOCK DEVICE" ATA command. There is an attempt limit, normally set to 5, after which the disk must be power cycled or hard-reset before unlocking can be attempted again. Also in High security mode, the SECURITY ERASE UNIT command can be used with either the User or Master password. + +In Maximum security mode, the device can be unlocked only with the User password. If the User password is not available, the only remaining way to get at least the bare hardware back to a usable state is to issue the SECURITY ERASE PREPARE command, immediately followed by SECURITY ERASE UNIT. In Maximum security mode, the SECURITY ERASE UNIT command requires the Master password and will completely erase all data on the disk. Word 89 in the IDENTIFY response indicates how long the operation will take. + +While the ATA lock is intended to be impossible to defeat without a valid password, there are purported workarounds to unlock a device. + +For sanitizing entire disks the built-in Secure Erase command is effective when implemented correctly. There have been a few reported instances of failures to erase some or all data. + +External parallel ATA devices + +Due to a short cable length specification and shielding issues it is extremely uncommon to find external PATA devices that directly use PATA for connection to a computer. A device connected externally needs additional cable length to form a U-shaped bend so that the external device may be placed alongside, or on top of the computer case, and the standard cable length is too short to permit this. For ease of reach from motherboard to device, the connectors tend to be positioned towards the front edge of motherboards, for connection to devices protruding from the front of the computer case. This front-edge position makes extension out the back to an external device even more difficult. Ribbon cables are poorly shielded, and the standard relies upon the cabling to be installed inside a shielded computer case to meet RF emissions limits. + +External hard disk drives or optical disk drives that have an internal PATA interface, use some other interface technology to bridge the distance between the external device and the computer. USB is the most common external interface, followed by Firewire. A bridge chip inside the external devices converts from the USB interface to PATA, and typically only supports a single external device without cable select or master/slave. + +Compact Flash interface + +Compact Flash in its IDE mode is essentially a miniaturized ATA interface, intended for use on devices that use flash memory storage. No interfacing chips or circuitry are required, other than to directly adapt the smaller CF socket onto the larger ATA connector. (Although most CF cards only support IDE mode up to PIO4, making them much slower in IDE mode than their CF capable speed) + +The ATA connector specification does not include pins for supplying power to a CF device, so power is inserted into the connector from a separate source. The exception to this is when the CF device is connected to a 44-pin ATA bus designed for 2.5-inch hard disk drives, commonly found in notebook computers, as this bus implementation must provide power to a standard hard disk drive. + +CF devices can be designated as devices 0 or 1 on an ATA interface, though since most CF devices offer only a single socket, it is not necessary to offer this selection to end users. Although CF can be hot-pluggable with additional design methods, by default when wired directly to an ATA interface, it is not intended to be hot-pluggable. + +ATA standards versions, transfer rates, and features +The following table shows the names of the versions of the ATA standards and the transfer modes and rates supported by each. Note that the transfer rate for each mode (for example, 66.7 MB/s for UDMA4, commonly called "Ultra-DMA 66", defined by ATA-5) gives its maximum theoretical transfer rate on the cable. This is simply two bytes multiplied by the effective clock rate, and presumes that every clock cycle is used to transfer end-user data. In practice, of course, protocol overhead reduces this value. + +Congestion on the host bus to which the ATA adapter is attached may also limit the maximum burst transfer rate. For example, the maximum data transfer rate for conventional PCI bus is 133 MB/s, and this is shared among all active devices on the bus. + +In addition, no ATA hard drives existed in 2005 that were capable of measured sustained transfer rates of above 80 MB/s. Furthermore, sustained transfer rate tests do not give realistic throughput expectations for most workloads: They use I/O loads specifically designed to encounter almost no delays from seek time or rotational latency. Hard drive performance under most workloads is limited first and second by those two factors; the transfer rate on the bus is a distant third in importance. Therefore, transfer speed limits above 66 MB/s really affect performance only when the hard drive can satisfy all I/O requests by reading from its internal cache—a very unusual situation, especially considering that such data is usually already buffered by the operating system. + +, mechanical hard disk drives can transfer data at up to 524 MB/s, which is far beyond the capabilities of the PATA/133 specification. High-performance solid state drives can transfer data at up to 7000–7500 MB/s. + +Only the Ultra DMA modes use CRC to detect errors in data transfer between the controller and drive. This is a 16-bit CRC, and it is used for data blocks only. Transmission of command and status blocks do not use the fast signaling methods that would necessitate CRC. For comparison, in Serial ATA, 32-bit CRC is used for both commands and data. + +Features introduced with each ATA revision + +Speed of defined transfer modes + +Related standards, features, and proposals + +ATAPI Removable Media Device (ARMD) + +ATAPI devices with removable media, other than CD and DVD drives, are classified as ARMD (ATAPI Removable Media Device) and can appear as either a super-floppy (non-partitioned media) or a hard drive (partitioned media) to the operating system. These can be supported as bootable devices by a BIOS complying with the ATAPI Removable Media Device BIOS Specification, originally developed by Compaq Computer Corporation and Phoenix Technologies. It specifies provisions in the BIOS of a personal computer to allow the computer to be bootstrapped from devices such as Zip drives, Jaz drives, SuperDisk (LS-120) drives, and similar devices. + +These devices have removable media like floppy disk drives, but capacities more commensurate with hard drives, and programming requirements unlike either. Due to limitations in the floppy controller interface most of these devices were ATAPI devices, connected to one of the host computer's ATA interfaces, similarly to a hard drive or CD-ROM device. However, existing BIOS standards did not support these devices. An ARMD-compliant BIOS allows these devices to be booted from and used under the operating system without requiring device-specific code in the OS. + +A BIOS implementing ARMD allows the user to include ARMD devices in the boot search order. Usually an ARMD device is configured earlier in the boot order than the hard drive. Similarly to a floppy drive, if bootable media is present in the ARMD drive, the BIOS will boot from it; if not, the BIOS will continue in the search order, usually with the hard drive last. + +There are two variants of ARMD, ARMD-FDD and ARMD-HDD. Originally ARMD caused the devices to appear as a sort of very large floppy drive, either the primary floppy drive device 00h or the secondary device 01h. Some operating systems required code changes to support floppy disks with capacities far larger than any standard floppy disk drive. Also, standard-floppy disk drive emulation proved to be unsuitable for certain high-capacity floppy disk drives such as Iomega Zip drives. Later the ARMD-HDD, ARMD-"Hard disk device", variant was developed to address these issues. Under ARMD-HDD, an ARMD device appears to the BIOS and the operating system as a hard drive. + +ATA over Ethernet +In August 2004, Sam Hopkins and Brantley Coile of Coraid specified a lightweight ATA over Ethernet protocol to carry ATA commands over Ethernet instead of directly connecting them to a PATA host adapter. This permitted the established block protocol to be reused in storage area network (SAN) applications. + +See also + + Advanced Host Controller Interface (AHCI) + CE-ATA Consumer Electronics (CE) ATA + FATA (hard drive) + INT 13H for BIOS Enhanced Disk Drive Specification (SFF-8039i) + IT8212, a low-end Parallel ATA controller + Master/slave (technology) + List of device bandwidths + +References + +External links + CE-ATA Workgroup + +AT Attachment +Computer storage buses +Computer connectors +Computer hardware standards +The Atari 2600 is a home video game console developed and produced by Atari, Inc. Released in September 1977, it popularized microprocessor-based hardware and games stored on swappable ROM cartridges, a format first used with the Fairchild Channel F in 1976. Branded as the Atari Video Computer System (Atari VCS) from its release until November 1982, the VCS was bundled with two joystick controllers, a conjoined pair of paddle controllers, and a game cartridgeinitially Combat and later Pac-Man. + +Atari was successful at creating arcade video games, but their development cost and limited lifespan drove CEO Nolan Bushnell to seek a programmable home system. The first inexpensive microprocessors from MOS Technology in late 1975 made this feasible. The console was prototyped as codename Stella by Atari subsidiary Cyan Engineering. Lacking funding to complete the project, Bushnell sold Atari to Warner Communications in 1976. + +The Atari VCS launched in 1977 with nine simple, low-resolution games in 2 KB cartridges. The system's first killer app was the home conversion of Taito's arcade game Space Invaders in 1980. The VCS became widely successful, leading to the founding of Activision and other third-party game developers and to competition from console manufacturers Mattel and Coleco. By the end of its primary lifecycle in 1983–84, games for the 2600 were using more than four times the storage size of the launch games with significantly more advanced visuals and gameplay than the system was designed for, such as Activision's Pitfall! + +By 1982, the Atari 2600 was the dominant game system in North America. However, it saw competition from other consoles such as the Intellivision and ColecoVision, and poor decisions by Atari management damaged both the system and company's reputation, most notably the release of two highly anticipated games for the 2600: a port of the arcade game Pac-Man and E.T. the Extra-Terrestrial. Pac-Man became the 2600's highest-selling game, but was panned for being inferior to the arcade version. E.T. was rushed to market for the holiday shopping season and was similarly panned and became a commercial failure. Both games, and a glut of third-party shovelware, were factors in ending Atari's relevance in the console market, contributing to the video game crash of 1983. + +Warner sold Atari's home division to former Commodore CEO Jack Tramiel in 1984. In 1986, the new Atari Corporation under Tramiel released a lower-cost version of the 2600 and the backward-compatible Atari 7800, but it was Nintendo that led the recovery of the industry with its 1985 launch of the Nintendo Entertainment System. Production of the Atari 2600 ended on January 1, 1992, with an estimated 30 million units sold across its lifetime. + +History + +Atari, Inc. was founded by Nolan Bushnell and Ted Dabney in 1972. Its first major product was Pong, released in 1972, the first successful coin-operated video game. While Atari continued to develop new arcade games in following years, Pong gave rise to a number of competitors to the growing arcade game market. The competition along with other missteps by Atari led to financial problems in 1974, though recovering by the end of the year. By 1975, Atari had released a Pong home console, competing against Magnavox, the only other major producer of home consoles at the time. Atari engineers recognized, however, the limitation of custom logic integrated onto the circuit board, permanently confining the whole console to only one game. The increasing competition increased the risk, as Atari had found with past arcade games and again with dedicated home consoles. Both platforms are built from integrating discrete electro-mechanical components into circuits, rather than programmed as on a mainframe computer. Therefore, development of a console had cost at least plus time to complete, but the final product only had about a three-month shelf life until becoming outdated by competition. + +By 1974, Atari had acquired Cyan Engineering, a Grass Valley electronics company founded by Steve Mayer and Larry Emmons, both former colleagues of Bushnell and Dabney from Ampex, who helped to develop new ideas for Atari's arcade games. Even prior to the release of the home version of Pong, Cyan's engineers, led by Mayer and Ron Milner, had envisioned a home console powered by new programmable microprocessors capable of playing Atari's current arcade offerings. The programmable microprocessors would make a console's design significantly simpler and more powerful than any dedicated single-game unit. However, the cost of such chips was far outside the range that their market would tolerate. Atari had opened negotiations to use Motorola's new 6800 in future systems. + +MOS Technology 6502/6507 +In September 1975, MOS Technology debuted the 6502 microprocessor for at the Wescon trade show in San Francisco. Mayer and Milner attended, and met with the leader of the team that created the chip, Chuck Peddle. They proposed using the 6502 in a game console, and offered to discuss it further at Cyan's facilities after the show. + +Over two days, MOS and Cyan engineers sketched out a 6502-based console design by Meyer and Milner's specifications. Financial models showed that even at , the 6502 would be too expensive, and Peddle offered them a planned 6507 microprocessor, a cost-reduced version of the 6502, and MOS's RIOT chip for input/output. Cyan and MOS negotiated the 6507 and RIOT chips at a pair. MOS also introduced Cyan to Microcomputer Associates, who had separately developed debugging software and hardware for MOS, and had developed the JOLT Computer for testing the 6502, which Peddle suggested would be useful for Atari and Cyan to use while developing their system. Milner was able to demonstrate a proof-of-concept for a programmable console by implementing Tank, an arcade game by Atari's subsidiary Kee Games, on the JOLT. + +As part of the deal, Atari wanted a second source of the chipset. Peddle and Paivinen suggested Synertek whose co-founder, Bob Schreiner, was a friend of Peddle. In October 1975, Atari informed the market that it was moving forward with MOS. The Motorola sales team had already told its management that the Atari deal was finalized, and Motorola management was livid. They announced a lawsuit against MOS the next week. + +Building the system + +By December 1975, Atari hired Joe Decuir, a recent graduate from University of California, Berkeley who had been doing his own testing on the 6502. Decuir began debugging the first prototype designed by Mayer and Milner, which gained the codename "Stella" after the brand of Decuir's bicycle. This prototype included a breadboard-level design of the graphics interface to build upon. A second prototype was completed by March 1976 with the help of Jay Miner, who created a chip called the Television Interface Adaptor (TIA) to send graphics and audio to a television. The second prototype included a TIA, a 6507, and a ROM cartridge slot and adapter. + +As the TIA's design was refined, Al Alcorn brought in Atari's game developers to provide input on features. There are significant limitations in the 6507, the TIA, and other components, so the programmers creatively optimized their games to maximize the console. The console lacks a framebuffer and requires games to instruct the system to generate graphics in synchronization with the electron gun in the cathode-ray tube (CRT) as it scans across rows on the screen. The programmers found ways to "race the beam" to perform other functions while the electron gun scans outside of the visible screen. + +Alongside the electronics development, Bushnell brought in Gene Landrum, a consultant who had just prior consulted for Fairchild Camera and Instrument for its upcoming Channel F, to determine the consumer requirements for the console. In his final report, Landrum suggested a living room aesthetic, with a wood grain finish, and the cartridges must be "idiot proof, child proof and effective in resisting potential static [electricity] problems in a living room environment". Landrum recommended it include four to five dedicated games in addition to the cartridges, but this was dropped in the final designs. The cartridge design was done by James Asher and Douglas Hardy. Hardy had been an engineer for Fairchild and helped in the initial design of the Channel F cartridges, but he quit to join Atari in 1976. The interior of the cartridge that Asher and Hardy designed was sufficiently different to avoid patent conflicts, but the exterior components were directly influenced by the Channel F to help work around the static electricity concerns. + +Atari was still recovering from its 1974 financial woes and needed additional capital to fully enter the home console market, though Bushnell was wary of being beholden to outside financial sources. Atari obtained smaller investments through 1975, but not at the scale it needed, and began considering a sale to a larger firm by early 1976. Atari was introduced to Warner Communications, which saw the potential for the growing video game industry to help offset declining profits from its film and music divisions. Negotiations took place during 1976, during which Atari cleared itself of liabilities, including settling a patent infringement lawsuit with Magnavox over Ralph H. Baer's patents that were the basis for the Magnavox Odyssey. In mid-1976, Fairchild announced the Channel F, planned for release later that year, beating Atari to the market. + +By October 1976, Warner and Atari agreed to the purchase of Atari for . Warner provided an estimated which was enough to fast-track Stella. By 1977, development had advanced enough to brand it the "Atari Video Computer System" (VCS) and start developing games. + +Launch and success + +The unit was showcased on June 4, 1977, at the Summer Consumer Electronics Show with plans for retail release in October. The announcement was purportedly delayed to wait out the terms of the Magnavox patent lawsuit settlement, which would have given Magnavox all technical information on any of Atari's products announced between June 1, 1976, and June 1, 1977. However, Atari encountered production problems during its first batch, and its testing was complicated by the use of cartridges. + +The Atari VCS was launched in September 1977 at , with two joysticks and a Combat cartridge; eight additional games were sold separately. Most of the launch games were based on arcade games developed by Atari or its subsidiary Kee Games: for example, Combat was based on Kee's Tank (1974) and Atari's Jet Fighter (1975). Atari sold between 350,000 and 400,000 Atari VCS units during 1977, attributed to the delay in shipping the units and consumers' unfamiliarity with a swappable-cartridge console that is not dedicated to only one game. + +In 1978, Atari sold only 550,000 of the 800,000 systems manufactured. This required further financial support from Warner to cover losses. Atari sold 1 million consoles in 1979, particularly during the holiday season, but there was new competition from the Mattel Electronics Intellivision and Magnavox Odyssey², which also use swappable ROM cartridges. The 2019 book They Create Worlds has Atari selling about 600,000 VCS systems in 1979, bringing the installed base to a little over 1.3 million. + +Atari obtained a license from Taito to develop a VCS conversion of its 1978 arcade hit Space Invaders. This is the first officially licensed arcade conversion for a home console. Its release in March 1980 doubled the console's sales for the year to more than 2 million units, and was considered the Atari VCS' killer application. Sales then doubled again for the next two years. The book They Create Worlds has Atari selling 1.25 million Space Invaders cartridges and over 1 million VCS systems in 1980, nearly doubling the install base to over 2 million, and then an estimated 3.1 million VCS systems in 1981. By 1982, 10 million consoles had been sold in the United States, while its best-selling game was Pac-Man at over copies sold by 1990. Pac-Man propelled worldwide Atari VCS sales to units during 1982, according to a November 1983 article in InfoWorld magazine. An August 1984 InfoWorld magazine article says more than Atari 2600 machines are sold by 1982. A March 1983 article in IEEE Spectrum magazine has about 3 million VCS sales in 1981, about 5.5 million in 1982, as well as a total of over 12 million VCS systems and estimated 120 million cartridges sold. + +In Europe, the Atari VCS sold 125,000 units in the United Kingdom during 1980, and 450,000 in West Germany by 1984. In France, where the VCS released in 1982, the system sold 600,000 units by 1989. The console was distributed by Epoch Co. in Japan in 1979 under the name "Cassette TV Game", but not sell as well as Epoch's own Cassette Vision system in 1981. + +In 1982, Atari launched its second programmable console, the Atari 5200. To standardize naming, the VCS was renamed to the "Atari 2600 Video Computer System", or "Atari 2600", derived from the manufacture part number CX2600. By 1982, the 2600 cost Atari about to make and was sold for an average of . The company spent .50 to to manufacture each cartridge, plus to for advertising, wholesaling for . + +Third-party development +Activision, formed by Crane, Whitehead, and Miller in 1979, started developing third-party VCS games using their knowledge of VCS design and programming tricks, and began releasing games in 1980. Kaboom! (1981) and Pitfall! (1982) are among the most successful with at least one and four million copies sold, respectively. In 1980, Atari attempted to block the sale of the Activision cartridges, accusing the four of intellectual property infringement. The two companies settled out of court, with Activision agreeing to pay Atari a licensing fee for their games. This made Activision the first third-party video game developer and established the licensing model that continues to be used by console manufacturers for game development. + +Activision's success led to the establishment of other third-party VCS game developers following Activision's model in the early 1980s, including U.S. Games, Telesys, Games by Apollo, Data Age, Zimag, Mystique, and CommaVid. The founding of Imagic included ex-Atari programmers. Mattel and Coleco, each already producing its own more advanced console, created simplified versions of their existing games for the 2600. Mattel used the M Network brand name for its cartridges. Third-party games accounted for half of VCS game sales by 1982. + +Decline and redesign +In addition to third-party game development, Atari also received the first major threat to its hardware dominance from the Colecovision. Coleco had a license from Nintendo to develop a version of the arcade game Donkey Kong (1981), which was bundled with every Colecovision console. Coleco gained about 17% of the hardware market in 1982 compared to Atari's 58%. With third parties competing for market share, Atari worked to maintain dominance in the market by acquiring licenses for popular arcade games and other properties to make games from. Pac-Man has numerous technical and aesthetic flaws, but nevertheless more than 7 million copies were sold. Heading into the 1982 holiday shopping season, Atari had placed high sales expectations on E.T. the Extra-Terrestrial, a game programmed in about six weeks. Atari produced an estimated four million cartridges, but the game was poorly reviewed, and only about 1.5 million units were sold. + +Warner Communications reported weaker results than expected in December 1982 to its shareholders, having expected a 50% year-to-year growth but only obtaining 10–15% due to declining sales at Atari. Coupled with the oversaturated home game market, Atari's weakened position led investors to start pulling funds out of video games, beginning a cascade of disastrous effects known as the video game crash of 1983. Many of the third-party developers formed prior to 1983 were closed, and Mattel and Coleco left the video game market by 1985. + +In September 1983, Atari sent 14 truckloads of unsold Atari 2600 cartridges and other equipment to a landfill in the New Mexico desert, later labeled the Atari video game burial. Long considered an urban legend that claimed the burial contained millions of unsold cartridges, the site was excavated in 2014, confirming reports from former Atari executives that only about 700,000 cartridges had actually been buried. Atari reported a loss for 1983 as a whole, and continued to lose money into 1984, with a loss reported in the second quarter. By mid-1984, software development for the 2600 had essentially stopped except that of Atari and Activision. + +Warner, wary of supporting its failing Atari division, started looking for buyers in 1984. Warner sold most of Atari to Jack Tramiel, the founder of Commodore International, in July 1984 for about , though Warner retained Atari's arcade business. Tramiel was a proponent of personal computers, and halted all new 2600 game development soon after the sale. + +The North American video game market did not recover until about 1986, after Nintendo's 1985 launch of the Nintendo Entertainment System in North America. Atari Corporation released a redesigned model of the 2600 in 1986, supported by an ad campaign touting a price of "under 50 bucks". With a large library of cartridges and a low price point, the 2600 continued to sell into the late 1980s. Atari released the last batch of games in 1989–90 including Secret Quest and Fatal Run. By 1986, over Atari VCS units had been sold worldwide. The final Atari-licensed release is the PAL-only version of the arcade game KLAX in 1990. + +After more than 14 years on the market, the 2600 line was formally discontinued on January 1, 1992, along with the Atari 7800 and Atari 8-bit family of home computers. In Europe, last stocks of the 2600 were sold until Summer/Fall of 1995. + +Hardware + +Console + +The Atari 2600's CPU is the MOS Technology 6507, a version of the 6502, running at 1.19 MHz in the 2600. Though their internal silicon was identical, the 6507 was cheaper than the 6502 because its package included fewer memory-address pins—13 instead of 16. The designers of the Atari 2600 selected an inexpensive cartridge interface that has one fewer address pins than the 13 allowed by the 6507, further reducing the already limited addressable memory from 8 KB (213 = 8,192) to 4 KB (212 = 4,096). This was believed to be sufficient as Combat is itself only 2 KB. Later games circumvented this limitation with bank switching. + +The console has 128 bytes of RAM for scratch space, the call stack, and the state of the game environment. + +The top bezel of the console originally had six switches: power, TV type selection (color or black-and-white), game selection, player difficulty, and game reset. The difficulty switches were moved to the back of the bezel in later versions of the console. The back bezel also included the controller ports, TV output, and power input. + +Graphics + +The Atari 2600 was designed to be compatible with the cathode-ray tube television sets produced in the late 1970s and early 1980s, which commonly lack auxiliary video inputs to receive audio and video from another device. Therefore, to connect to a TV, the console generates a radio frequency signal compatible with the regional television standards (NTSC, PAL, or SECAM), using a special switch box to act as the television's antenna. + +Atari developed the Television Interface Adaptor (TIA) chip in the VCS to handle the graphics and conversion to a television signal. It provides a single-color, 20-bit background register that covers the left half of the screen (each bit represents 4 adjacent pixels) and is either repeated or reflected on the right side. There are 5 single-color sprites: two 8-pixel wide players; two 1 bit missiles, which share the same colors as the players; and a 1-pixel ball, which shares the background color. The 1-bit sprites all can be controlled to stretch to 1, 2, 4, or 8 pixels. + +The system was designed without a frame buffer to avoid the cost of the associated RAM. The background and sprites apply to a single scan line, and as the display is output to the television, the program can change colors, sprite positions, and background settings. The careful timing required to sync the code to the screen on the part of the programmer was labeled "racing the beam"; the actual game logic runs when the television beam is outside of the visible area of the screen. Early games for the system use the same visuals for pairs of scan lines, giving a lower vertical resolution, to allow more time for the next row of graphics to be prepared. Later games, such as Pitfall!, change the visuals for each scan line or extend the black areas around the screen to extend the game code's processing time. + +Regional releases of the Atari 2600 use modified TIA chips for each region's television formats, which require games to be developed and published separately for each region. All modes are 160 pixels wide. NTSC mode provides 192 visible lines per screen, drawn at 60 Hz, with 16 colors, each at 8 levels of brightness. PAL mode provides more vertical scanlines, with 228 visible lines per screen, but drawn at 50 Hz and only 13 colors. SECAM mode, also a 50 Hz format, is limited to 8 colors, each with only a single brightness level. + +Controllers + +The first VCS bundle has two types of controllers: a joystick (part number CX10) and pair of rotary paddle controllers (CX30). Driving controllers, which are similar to paddle controllers but can be continuously rotated, shipped with the Indy 500 launch game. After less than a year, the CX10 joystick was replaced with the CX40 model designed by James C. Asher. Because the Atari joystick port and CX40 joystick became industry standards, 2600 joysticks and some other peripherals work with later systems, including the MSX, Commodore 64, Amiga, Atari 8-bit family, and Atari ST. The CX40 joystick can be used with the Master System and Sega Genesis, but does not provide all the buttons of a native controller. Third-party controllers include Wico's Command Control joystick. Later, the CX42 Remote Control Joysticks, similar in appearance but using wireless technology, were released, together with a receiver whose wires could be inserted in the controller jacks. + +Atari introduced the CX50 Keyboard Controller in June 1978 along with two games that require it: Codebreaker and Hunt & Score. The similar, but simpler, CX23 Kid's Controller was released later for a series of games aimed at a younger audience. The CX22 Trak-Ball controller was announced in January 1983 and is compatible with the Atari 8-bit family. + +There were two attempts to turn the Atari 2600 into a keyboard-equipped home computer: Atari's never-released CX3000 "Graduate" keyboard, and the CompuMate keyboard by Spectravideo which was released in 1983. + +Console models + +Minor revisions +The initial production of the VCS was made in Sunnyvale during 1977, using thick polystyrene plastic for the casing as to give the impression of weight from what was mostly an empty shell inside. The initial Sunnyvale batch had also included potential mounts for an internal speaker system on the casing, though the speakers were found to be too expensive to include and instead sound was routed through the TIA to the connected television. All six console switches on the front panel. Production of the unit was moved to Taiwan in 1978, where a less thick internal metal shielding was used and thinner plastic was used for the casing, reducing the system's weight. These two versions are commonly referred to as "Heavy Sixers" and "Light Sixers" respectively, referencing the six front switches. + +In 1980, the difficulty switches were moved to the back of the console, leaving four switches on the front. Otherwise, these four-switch consoles look nearly identical to the earlier six-switch models. In 1982 Atari rebranded the console as the "Atari 2600", a name first used on a version of the four-switch model without woodgrain, giving it an all-black appearance. + +Sears Video Arcade +Atari continued its OEM relationship with Sears under the latter's Tele-Games brand, which started in 1975 with the original Pong. This is unrelated to the company Telegames, which later produced 2600 cartridges. Sears released several models of the VCS as the Sears Video Arcade series starting in 1977. In 1983, the previously Japan-only Atari 2800 was rebranded as the Sears Video Arcade II. + +Sears released versions of Atari's games with Tele-Games branding, usually with different titles. Three games were produced by Atari for Sears as exclusive releases: Steeplechase, Stellar Track, and Submarine Commander. + +Atari 2800 +The Atari 2800 is the Japanese version of the 2600 released in October 1983. It is the first Japan-specific release of a 2600, though companies like Epoch had distributed the 2600 in Japan previously. The 2800 was released a short time after Nintendo's Family Computer (which became the dominant console in Japan), and it did not gain a significant share of the market. Sears previously released the 2800 in the US during late 1982 as the Sears Video Arcade II, which came packaged with two controllers and Space Invaders. Around 30 specially branded games were released for the 2800. + +Designed by engineer Joe Tilly, the 2800 has four controller ports instead of the two of the 2600. The controllers are an all-in one design using a combination of an 8-direction digital joystick and a 270-degree paddle, designed by John Amber. The 2800's case design departed from the 2600, using a wedge shape with non-protruding switches. The case style is the basis for the Atari 7800, which was redesigned for the 7800 by Barney Huang. + +Atari 2600 Jr. +The 1986 model has a smaller, cost-reduced form factor with an Atari 7800-like appearance. It was advertised as a budget gaming system (under ) with the ability to run a large collection of games. Released after the video game crash of 1983, and after the North American launch of the Nintendo Entertainment System, the 2600 was supported with new games and television commercials promoting "The fun is back!". Atari released several minor stylistic variations: the "large rainbow" (shown), "short rainbow", and an all-black version sold only in Ireland. Later European versions include a joypad. + +Unreleased prototypes +The Atari 2700 was a version of the 2600 with wireless controllers. + +The CX2000, with integrated joystick controllers, was a redesign based on human factor analysis by Henry Dreyfuss Associates. + +The circa-1982 Atari 3200 was a backward compatible 2600 successor. + +Related hardware +The Atari 7800, announced in 1984 and released in 1986, is the official successor to the Atari 2600 and is backward compatible with 2600 cartridges. + +Multiple microconsoles are based on the Atari 2600: +The TV Boy includes 127 games in an enlarged joypad. +The Atari Classics 10-in-1 TV Game, manufactured by Jakks Pacific, emulates the 2600 with ten games inside a Atari-style joystick with composite-video output. +The Atari Flashback 2 (2005) contains 40 games, with four additional programs unlocked by a cheat code. It is compatible with original 2600 controllers and can be modified to play original 2600 cartridges. +In 2017, Hyperkin announced the RetroN 77, a clone of the Atari 2600 that plays original cartridges instead of preinstalled games. +The Atari VCS (2021 console) can download and emulate 2600 games via an online store. +Atari, Inc. plans to release the Atari 2600+, an 80% scale replica of the 1980 CX2600-A model, on November 17, 2023. The 2600+ includes support for original Atari 2600 and 7200 cartridges. + +Games + +In 1977, nine games were released on cartridge to accompany the launch of the console: Air-Sea Battle, Basic Math, Blackjack, Combat, Indy 500, Star Ship, Street Racer, Surround, and Video Olympics. Indy 500 shipped with special "driving controllers", which are like paddles but rotate freely. Street Racer and Video Olympics use the standard paddle controllers. +Atari, Inc. was the only developer for the first few years, releasing dozens of games. + +Atari determined that box art featuring only descriptions of the game and screenshots would not be sufficient to sell games in retail stores, since most games were based on abstract principles and screenshots give little information. Atari outsourced box art to Cliff Spohn, who created visually interesting artwork with implications of dynamic movement intended to engage the player's imagination while staying true to the gameplay. Spohn's style became a standard for Atari when bringing in assistant artists, including Susan Jaekel, Rick Guidice, John Enright, and Steve Hendricks. Spohn and Hendricks were the largest contributors to the covers in the Atari 2600 library. Ralph McQuarrie, a concept artist on the Star Wars series, was commissioned for one cover, the arcade conversion of Vanguard. These artists generally conferred with the programmer to learn about the game before drawing the art. + +An Atari VCS port of the Breakout arcade game appeared in 1978. The original is in black and white with a colored overlay, and the home version is in color. In 1980, Atari released Adventure, the first action-adventure game, and the first home game with a hidden Easter egg. + +Rick Maurer's port of Taito's Space Invaders, released in 1980, is the first VCS game to have more than one million copies sold—eventually doubling that within a year and totaling more than cartridges by 1983. It became the killer app to drive console sales. Versions of Atari's own Asteroids and Missile Command arcade games, released in 1981, were also major hits. + +Each early VCS game is in a 2K ROM. Later games, like Space Invaders, have 4K. The VCS port of Asteroids (1981) is the first game for the system to use 8K via a bank switching technique between two 4K segments. Some later releases, including Atari's ports of Dig Dug and Crystal Castles, are 16K cartridges. One of the final games, Fatal Run (1990), doubled this to 32K. + +Two Atari-published games, both from the system's peak in 1982, E.T. the Extra-Terrestrial and Pac-Man, are cited as factors in the video game crash of 1983. + +A company named American Multiple Industries produced a number of pornographic games for the 2600 under the Mystique Presents Swedish Erotica label. The most notorious, Custer's Revenge, was protested by women's and Native American groups because it depicted General George Armstrong Custer raping a bound Native American woman. Atari sued American Multiple Industries in court over the release of the game. + +Legacy + +The 2600 was so successful in the late 1970s and early 1980s that "Atari" was a synonym for the console in mainstream media and for video games in general. Jay Miner directed the creation of the successors to the 2600's TIA chip—CTIA and ANTIC—which are central to the Atari 8-bit computers released in 1979 and later the Atari 5200 console. + +The Atari 2600 was inducted into the National Toy Hall of Fame at The Strong in Rochester, New York, in 2007. In 2009, the Atari 2600 was named the number two console of all time by IGN, which cited its remarkable role behind both the first video game boom and the video game crash of 1983, and called it "the console that our entire industry is built upon". + +In November 2021, the current incarnation of Atari announced three 2600 games to be published under "Atari XP" label: Yars' Return, Aquaventure, and Saboteur. These were previously included in Atari Flashback consoles. + +Notes + +References + +Citations + +General bibliography + +External links + + A history of the Atari VCS/2600 + Inside the Atari 2600 + Hardware and prototypes at the Atari Museum + + +1970s toys +1980s toys +2600 +Computer-related introductions in 1977 +Home video game consoles +Products and services discontinued in 1992 +Second-generation video game consoles +65xx-based video game consoles +Discontinued video game consoles +The Atari 5200 SuperSystem or simply Atari 5200 is a home video game console introduced in 1982 by Atari, Inc. as a higher-end complement for the popular Atari Video Computer System. The VCS was renamed to the Atari 2600 at the time of the 5200's launch. Created to compete with Mattel's Intellivision, the 5200 wound up a direct competitor of ColecoVision shortly after its release. While the Coleco system shipped with the first home version of Nintendo's Donkey Kong, the 5200 included the 1978 arcade game Super Breakout which had already appeared on the Atari 8-bit family and Atari VCS in 1979 and 1981 respectively. + +The CPU and the graphics and sound hardware are almost identical to that of the Atari 8-bit computers, although software is not directly compatible between the two systems. The 5200's controllers have an analog joystick and a numeric keypad along with start, pause, and reset buttons. The 360-degree non-centering joystick was touted as offering more control than the eight-way Atari CX40 joystick of the 2600, but was a focal point for criticism. + +On May 21, 1984, during a press conference at which the Atari 7800 was introduced, company executives revealed that the 5200 had been discontinued after less than two years on the market. Total sales of the 5200 were reportedly in excess of 1 million units, far short of its predecessor's sales of over 30 million. + +Hardware + +Much of the technology in the Atari 8-bit family of home computer was originally developed as a second-generation games console intended to replace the Atari Video Computer System console. However, as the system was reaching completion, the personal computer revolution was starting with the release of machines like the Commodore PET, TRS-80, and Apple II. These machines had less advanced hardware than the new Atari technology, but sold for much higher prices with associated higher profit margins. Atari's management decided to enter this market, and the technology was repackaged into the Atari 400 and 800. The chipset used in these machines was created with the mindset that the VCS would likely be obsolete by 1980. + +Atari later decided to re-enter the games market with a design that closely matched their original 1978 specifications. In its prototype stage, the Atari 5200 was originally called the "Atari Video System X – Advanced Video Computer System", and was codenamed "Pam" after a female employee at Atari, Inc. It is also rumored that PAM actually stood for "Personal Arcade Machine", as the majority of games for the system ended up being arcade conversions. Actual working Atari Video System X machines, whose hardware is 100% identical to the Atari 5200 do exist, but are extremely rare. + +The initial 1982 release of the system featured four controller ports, where nearly all other systems of the day had only one or two ports. The 5200 also featured a new style of controller with an analog joystick, numeric keypad, two fire buttons on each side of the controller and game function keys for Start, Pause, and Reset. The 5200 also featured the innovation of the first automatic TV switchbox, allowing it to automatically switch from regular TV viewing to the game system signal when the system was activated. Previous RF adapters required the user to slide a switch on the adapter by hand. The RF box was also where the power supply connected in a unique dual power/television signal setup similar to the RCA Studio II's. A single cable coming out of the 5200 plugged into the switch box and carried both electricity and the television signal. + +The 1983 revision of the Atari 5200 has two controller ports instead of four, and a change back to the more conventional separate power supply and standard non-autoswitching RF switch. It also has changes in the cartridge port address lines to allow for the Atari 2600 adapter released that year. While the adapter was only made to work on the two-port version, modifications can be made to the four-port to make it line-compatible. In fact, towards the end of the four-port model's production run, there were a limited number of consoles produced which included these modifications. These consoles can be identified by an asterisk in their serial numbers. + +At one point following the 5200's release, Atari planned a smaller, cost-reduced version of the Atari 5200, which removed the controller storage bin. Code-named the "Atari 5100" (a.k.a. "Atari 5200 Jr."), only a few fully working prototype 5100s were made before the project was canceled. + +Controllers + +The controller prototypes used in the electrical development lab employed a yoke-and-gimbal mechanism that came from an RC airplane controller kit. The design of the analog joystick, which used a weak rubber boot rather than springs to provide centering, proved to be ungainly and unreliable. They quickly became the Achilles' heel of the system due to the combination of an overly complex mechanical design and a very low-cost internal flex circuit system. Another major flaw of the controllers was that the design did not translate into a linear acceleration from the center through the arc of the stick travel. The controllers did, however, include a pause button, a unique feature at the time. Various third-party replacement joysticks were also released, including those made by Wico. + +Atari Inc. released the Pro-Line Trak-Ball controller for the system, which was used primarily for gaming titles such as Centipede and Missile Command. A paddle controller and an updated self-centering version of the original controller were also in development, but never made it to market. + +Games were shipped with plastic card overlays that snapped in over the keypad. The card would indicate which game functions, such as changing the view or vehicle speed, were assigned to each key. + +The primary controller was ranked the 10th worst video game controller by IGN editor Craig Harris. An editor for Next Generation said that their non-centering joysticks "rendered many games nearly unplayable". + +Internal differences from 8-bit computers +David H. Ahl in 1983 described the Atari 5200 as "a 400 computer in disguise". Its internal design is a tweaked version of the Atari 8-bit family using the ANTIC, POKEY, and GTIA coprocessors. Software designed for one does not run on the other, but source code can be mechanically converted unless it uses computer-specific features. Antic magazine reported in 1984 that "the similarities grossly outweigh the differences, so that a 5200 program can be developed and almost entirely debugged [on an Atari 8-bit computer] before testing on a 5200". John J. Anderson of Creative Computing alluded to the incompatibility being intentional, caused by Atari's console division removing 8-bit compatibility to not lose control to the rival computer division. + +Besides the 5200's lack of a keyboard, the differences are: + The Atari computer 10 KB operating system is replaced with a simpler 2 KB version, of which 1 KB is the built-in character set. + Some hardware registers, such as those of the GTIA and POKEY chips, are at different memory locations. + The purpose of some registers is slightly different on the 5200. + The 5200's analog joysticks appear as pairs of paddles to the hardware, which requires different input handling from the digital joystick input on the Atari computers + +In 1987, Atari Corporation released the XE Game System console, which is a repackaged 65XE (from 1985) with a detachable keyboard that can run home computer titles directly, unlike the 5200. Anderson wrote in 1984 that Atari could have released a console compatible with computer software in 1981. + +Reception + +The Atari 5200 did not fare well commercially compared to its predecessor, the Atari 2600. While it touted superior graphics to the 2600 and Mattel's Intellivision, the system was initially incompatible with the 2600's expansive library of games, and some market analysts have speculated that this hurt its sales, especially since an Atari 2600 cartridge adapter had been released for the Intellivision II. (A revised two-port model was released in 1983, along with a game adapter that allowed gamers to play all 2600 games.) This lack of new games was due in part to a lack of funding, with Atari continuing to develop most of its games for the saturated 2600 market. + +Many of the 5200's games appeared simply as updated versions of 2600 titles, which failed to excite consumers. Its pack-in game, Super Breakout, was criticized for not doing enough to demonstrate the system's capabilities. This gave the ColecoVision a significant advantage as its pack-in, Donkey Kong, delivered a more authentic arcade experience than any previous game cartridge. In its list of the top 25 game consoles of all time, IGN claimed that the main reason for the 5200's market failure was the technological superiority of its competitor, while other sources maintain that the two consoles are roughly equivalent in power. + +The 5200 received much criticism for the "sloppy" design of its non-centering analog controllers. Anderson described the controllers as "absolutely atrocious". + +David H. Ahl of Creative Computing Video & Arcade Games said in 1983 that the "Atari 5200 is, dare I say it, Atari's answer to Intellivision, Colecovision, and the Astrocade", describing the console as a "true mass market" version of the Atari 8-bit computers despite the software incompatibility. He criticized the joystick's imprecise control but said that "it is at least as good as many other controllers", and wondered why Super Breakout was the pack-in game when it did not use the 5200's improved graphics. + +Technical specifications + + CPU: Custom MOS Technology 6502C @ 1.79 MHz (not a 65C02) + Graphics chips: ANTIC and GTIA + Support hardware: 3 custom VLSI chips + Screen resolution: 14 modes: Six text modes (8×8, 4×8, and 8×10 character matrices supported), Eight graphics modes including 80 pixels per line (16 color), 160 pixels per line (4 color), 320 pixels per line (2 color), variable height and width up to overscan 384×240 pixels + Color palette: 128 (16 hues, 8 luma) or 256 (16 hues, 16 luma) + Colors on screen: 2 (320 pixels per line) to 16 (80 pixels per line). Up to 23 colors per line with player/missile and playfield priority control mixing. Register values can be changed at every scanline using ANTIC display list interrupts, allowing up to 256 (16 hues, 16 luma) to be displayed at once, with up to 16 per scanline. + Sprites: Four 8-pixel-wide sprites, four 2-pixel-wide sprites; height of each is either 128 or 256 pixels; 1 color per sprite + Scrolling: Coarse and fine scrolling horizontally and vertically. (Horizontal coarse scroll 4, 8, or 16-pixel/color clock increments, and vertically by mode line height 2, 4, 8, or 16 scan lines.) (Or horizontal fine scroll 0 to 3, 7, or 15 single-pixel/color clock increments and then a 4, 8, or 16-pixel/color clock increment coarse scroll; and vertical fine scroll 0 to 1, 3, 7, or 15 scan line increments and then a 2, 4, 8, or 16 scan line increment coarse scroll) + Sound: 4-channel PSG sound via POKEY sound chip, which also handles keyboard scanning, serial I/O, high resolution interrupt capable timers (single cycle accurate), and random number generation. + RAM: 16 KB + ROM: + 2 KB on-board BIOS for system startup and interrupt routing. + 32 KB ROM window for standard game cartridges, expandable using bank switching techniques. + Dimensions: 13" × 15" × 4.25" + +Popular culture +Critical to the plot of the 1984 film Cloak & Dagger is an Atari 5200 game cartridge called Cloak & Dagger. The arcade version appears in the movie; in actuality the Atari 5200 version was started but never completed. The game was under development with the title Agent X when the movie producers and Atari learned of each other's projects and decided to cooperate. This collaboration was part of a larger phenomenon, of films featuring video games as critical plot elements (as with Tron and The Last Starfighter) and of video game tie-ins to the same films (as with the Tron games for the Intellivision and other platforms). + +Games + +See also + List of Atari 5200 emulators + Video game crash of 1983 + +References + +External links + + AtariAge – Comprehensive Atari 5200 database and information + Atari Museum 5200 Super System section + +5200 +Home video game consoles +Second-generation video game consoles +Products introduced in 1982 +65xx-based video game consoles +Discontinued video game consoles +The Atari 7800 ProSystem, or simply the Atari 7800, is a home video game console officially released by Atari Corporation in 1986 as the successor to both the Atari 2600 and Atari 5200. It can run almost all Atari 2600 cartridges, making it one of the first consoles with backward compatibility. It shipped with a different model of joystick from the 2600-standard CX40 and Pole Position II as the pack-in game. Most of the announced titles at launch were ports of 1981–1983 arcade video games. + +Designed by General Computer Corporation, the 7800 has significantly improved graphics hardware over Atari's previous consoles, but the same Television Interface Adaptor chip that launched with the 2600 in 1977 is used to generate audio. In an effort to prevent the flood of poor quality games that contributed to the video game crash of 1983, cartridges had to be digitally signed by Atari. + +The Atari 7800 was first announced by Atari, Inc. on May 21, 1984, but a general release was shelved until May 1986 due to the sale of the company. Atari Corporation dropped support for the 7800, along with the 2600 and the Atari 8-bit family, on January 1, 1992. + +History +Atari had been facing pressure from Coleco and its ColecoVision console, which supported graphics that more closely mirrored arcade games of the time than either the Atari 2600 or 5200. The Atari 5200 (released as a successor to the Atari 2600) was criticized for not being able to play 2600 games without an adapter. + +The Atari 7800 ProSystem was the first console from Atari, Inc. designed by an outside company, General Computer Corporation. It was designed in 1983–84 with an intended mass market rollout in June 1984, but was canceled after the sale of the company to Tramel Technology Ltd on July 2, 1984. The project was originally called the Atari 3600. + +With a background in creating arcade games such as Food Fight, GCC designed the new system with a graphics architecture similar to arcade machines of the time. The CPU is a slightly customized 6502 processor, the Atari SALLY, running at 1.79 MHz. By some measures the 7800 is more powerful, and by others less, than the 1983 Nintendo Entertainment System. It uses the 2600's Television Interface Adaptor chip, with the same restrictions, for generating two-channels of audio. + +Launch +The 7800 was announced on May 21, 1984. Thirteen games were announced for the system's launch: Ms. Pac-Man, Pole Position II, Centipede, Joust, Dig Dug, Nile Flyer (eventually released as Desert Falcon), Robotron: 2084, Galaga, Food Fight, Ballblazer, Rescue on Fractalus! (later canceled), Track & Field, and Xevious. + +On July 2, 1984, Warner Communications sold Atari's Consumer Division to Jack Tramiel. All projects were halted during an initial evaluation period. GCC had not been paid for their development of the 7800, and Warner and Tramiel fought over who was accountable. In May 1985, Tramiel relented and paid GCC. This led to additional negotiations regarding the launch titles GCC had developed, then an effort to find someone to lead their new video game division, which was completed in November 1985. The original production run of the Atari 7800 languished in warehouses until it was introduced in January 1986. + +The console was released nationwide in May 1986 for $79.95. It launched with titles intended for the 7800's debut in 1984 and was aided by a marketing campaign with a budget in the "low millions" according to Atari Corporation officials. This was substantially less than the $9 million spent by Sega and the $16 million spent by Nintendo. The keyboard and high score cartridge planned by Warner were cancelled. + +In February 1987, Computer Entertainer reported that 100,000 Atari 7800 consoles had been sold in the United States, including those which had been warehoused since 1984. This was less than the Master System's 125,000 and the NES's 1.1 million. A complaint from owners in 1986 was the slow release of games. Galaga in August was followed by Xevious in November. By the end of 1986, the 7800 had 10 games, compared to Sega's 20 and Nintendo's 36. Atari would sell over 1 million 7800 consoles by June 1988. + +Discontinuation +On January 1, 1992, Atari Corporation announced the end of production and support for the 7800, 2600, and the 8-bit computer family including the Atari XEGS. At least one game, an unreleased port of Toki, was worked on past this date. By the time of the discontinuation, the Nintendo Entertainment System controlled 80% of the North American market while Atari had 12%. In Europe, last stocks of the 7800 were sold until summer/fall of 1995. + +Retro Gamer magazine issue 132 reported that according to Atari UK Marketing Manager Darryl Still, "it was very well stocked by European retail; although it never got the consumer traction that the 2600 did, I remember we used to sell a lot of units through mail order catalogues and in the less affluent areas". + +Technical specifications + + CPU: Atari SALLY (custom variant of the 6502) + 1.79 MHz, which drops to 1.19 MHz when the Television Interface Adaptor or (6532 RAM-I/O-Timer) chips are accessed + Unlike a standard 6502, SALLY can be halted in a known state with a single pin to let other devices control the bus. + Sometimes referred to by Atari as "6502C", but not the same as the official MOS Technology 6502C. + RAM: 4 KB (2 6116 2Kx8 RAM ICs) + ROM: built in 4 KB BIOS ROM, 48 KB Cartridge ROM space without bank switching + Graphics: MARIA custom chip + Resolution: 160×240 (160×288 PAL) or 320×240 (320×288 PAL) + Color palette: 256 (16 hues * 16 luma), different graphics modes restricted the number of usable colors and the number of colors per sprite + Direct Memory Access (DMA) + Graphics clock: 7.15 MHz + Line buffer: 200 bytes (double buffering), 160 sprite pixels per scanline, up to 30 sprites per scanline (without background), up to 100 sprites on screen + Sprite/zone sizes: 4 to 160 width, height of 4, 8 or 16 pixels + Colors per sprite: 1 to 12 (1 to 8 visible colors, 1 to 4 transparency bits) + I/O: Joystick and console switch IO handled by 6532 RIOT and TIA + Ports +2 joystick ports +cartridge port +expansion connector +power in +RF output + Sound: TIA as used in the 2600 for video and sound. In 7800 mode it is only used for sound. + At least two games include a POKEY sound chip for improved audio. + +Graphics +Graphics are generated by the custom MARIA chip, which uses an approach common in contemporary arcade system boards and is different from other second and third generation consoles. Instead of a limited number of hardware sprites, MARIA treats everything as a sprite described in a series of display lists. Each display list contains pointers to graphics data and color and positioning information. + +MARIA supports a palette of 256 colors and graphics modes which are either 160 pixels wide or 320 pixels wide. While the 320 pixel modes theoretically enable the 7800 to create games at higher resolution than the 256 pixel wide graphics found in the Nintendo Entertainment System and Master System, the processing demands of MARIA result in most games using the 160 pixel mode. + +Each sprite can have from 1 to 12 colors, with 3 colors plus transparency being the most common. In this format, the sprite references one of 8 palettes, where each palette holds 3 colors. The background–visible when not covered by other objects–can also be assigned a color. In total, 25 colors can appear on a scan line. + +The graphics resolution, color palettes, and background color can be adjusted between scan lines. This can be used to render high resolution text in one area of the screen, while displaying more colorful graphics at lower resolution in the gameplay area. + +Sound +The 7800 uses the TIA chip for two channel audio, the same chip used in the 1977 Atari VCS, and the sound is of the same quality as that system. To compensate, GCC's engineers allowed games to include a POKEY audio chip in the cartridge. Only Ballblazer and Commando do this. + +GCC planned to make a low-cost, high performance sound chip, GUMBY, which could also be placed in 7800 cartridges to enhance its sound capabilities further. This project was cancelled when Atari was sold to Jack Tramiel. + +Digitally signed cartridges +Following the large number of low quality, third party games for the Atari 2600, Atari required that cartridges for the 7800 be digitally signed. When a cartridge is inserted into the system, the BIOS generates a signature of the cartridge ROM and compares it to the one stored on the cartridge. If they match, the console operates in 7800 mode, granting the game access to MARIA and other features, otherwise the console operates as a 2600. This digital signature code is not present in PAL 7800s, which use various heuristics to detect 2600 cartridges, due to export restrictions. + +Backward compatibility +The 7800's compatibility with the Atari 2600 is made possible by including many of the same chips used in the 2600. When playing an Atari 2600 game, the 7800 uses a Television Interface Adaptor chip to generate graphics and sound. The processor is slowed to 1.19 MHz, to mirror the performance of the 2600's 6507 chip. RAM is limited to 128 bytes and cartridge data is accessed in 4K blocks. + +When in 7800 mode (signified by the appearance of the full-screen Atari logo), the graphics are generated entirely by the MARIA graphics processing unit. All system RAM is available and cartridge data is accessed in larger 48K blocks. The system's SALLY 6502 runs at its normal 1.79 MHz. The 2600 chips are used to generate sound and to provide the interfaces to the controllers and console switches. + +System revisions + +Initial version: two joystick ports on lower front panel. Side expansion port for upgrades and add-ons. Bundled with two CX24 Pro-Line joysticks, AC adapter, switchbox, RCA connecting cable, and Pole Position II cartridge. +Second revision: Slightly revised motherboard. Expansion port connector removed from motherboard but is still etched. Shell has indentation of where expansion port was to be. +Third revision: Same as above but with only a small blemish on the shell where the expansion port was. + +Peripherals + +The Atari 7800 came bundled with the Atari Pro-Line Joystick, a two-button controller with a joystick for movement. The Pro-Line was developed for the 2600 and advertised in 1983, but delayed until Atari proceeded with the 7800. The right fire button only works as a separate fire button for certain 7800 games; otherwise, it duplicates the left fire button, allowing either button to be used for 2600 games. While physically compatible, the 7800's controllers do not work with the Sega Master System, and Sega's controllers are unable to use the 7800's two-button mode. + +In response to criticism over ergonomic issues with the Pro-Line controllers, Atari later released a joypad controller with the European 7800. Similar in style to controllers found on Nintendo and Sega systems, it was not available in the United States. + +The Atari XG-1 light gun, bundled with the Atari XEGS and also sold separately, is compatible with the 7800. Atari released five 7800 light gun games: Alien Brigade, Barnyard Blaster, Crossbow, Meltdown, and Sentinel. + +Cancelled peripherals +After the acquisition of the Atari Consumer Division by Jack Tramiel in 1984, several expansion options for the system were cancelled: + + The High Score Cartridge was designed to save high scores for up to 65 separate games. The cartridge was intended as a pass-through device, similar to the later Game Genie. Nine games were programmed to support the cartridge. + The expansion port, to allow for the addition of a planned computer keyboard and connection to laserdisc players and other peripherals, was removed in the second and third revisions of the 7800. + A dual joystick holder was designed for Robotron: 2084 and future games like Battlezone, but not produced. + +Games + +While the system can play the over 400 games for the Atari 2600, there were only 59 official releases for the 7800. The lineup emphasized high-quality versions of games from the golden age of arcade video games. Pole Position II, Dig Dug, and Galaga, by the time of the 1986 launch, were three, four, and five years old, respectively. A raster graphics version of 1979's Asteroids was released in 1987. In 1988, Atari published a conversion of Nintendo's Donkey Kong, seven years after the original arcade game and five years after the Atari 8-bit family cartridge. Atari also marketed a line of games called "Super Games" which were arcade and computer games previously not playable on a home console such as One-On-One Basketball and Impossible Mission. + +Eleven games were developed and sold by three third-party companies under their own labels (Absolute Entertainment, Activision, and Froggo) with the rest published by Atari Corporation. Most of the games from Atari were developed by outside companies under contract. + +Some NES games were developed by companies who had licensed their title from a different arcade manufacturer. While the creator of the NES version would be restricted from making a competitive version of an NES game, the original arcade copyright holder was not precluded from licensing out rights for a home version of an arcade game to multiple systems. Through this loophole, Atari 7800 conversions of Mario Bros., Double Dragon, Commando, Rampage, Xenophobe, Ikari Warriors, and Kung-Fu Master were licensed and developed. + +A final batch of games was released by Atari in 1990: Alien Brigade, Basketbrawl, Fatal Run, Meltdown, Midnight Mutants, MotorPsycho, Ninja Golf, Planet Smashers, and Scrapyard Dog. Scrapyard Dog was later released for the Atari Lynx. + +Legacy + +Atari Flashback +In 2004, the Infogrames-owned version of Atari released the Atari Flashback console. It resembles a miniature Atari 7800 and has five 7800 and fifteen 2600 games built-in. Built using the NES-On-A-Chip hardware instead of recreating the Atari 7800 hardware, it was criticized for failing to properly replicate the actual gaming experience. A subsequent 7800 project was cancelled after prototypes were made. + +Game development +The digital signature long prevented aftermarket games from being developed. The signing software was eventually found and released at Classic Gaming Expo in 2001. +Several new Atari 7800 games such as Beef Drop, B*nQ, Combat 1990, CrazyBrix, Failsafe, and Santa Simon have been released.. + +Source code +The source code for 13 games, the operating system, and the development tools which run on the Atari ST were discovered in a dumpster behind the Atari building in Sunnyvale, California. Commented assembly language source code was made available for Centipede, Commando, Crossbow, Desert Falcon, Dig Dug, Food Fight, Galaga, Hat Trick, Joust, Ms. Pac-Man, Super Stunt Cycle, Robotron: 2084, and Xevious. + +See also + History of Atari + List of Atari 7800 games + List of Atari 2600 games + +References + +External links + + AtariAge – Comprehensive Atari 7800 database and information + Atari 7800 Information & Resources + Atari Museum – History of the Atari 7800 ProSystem + Atari 7800 Development Wiki + ProSystem emulator for Microsoft Windows + +7800 +Home video game consoles +Backward-compatible video game consoles +Third-generation video game consoles +1986 in video gaming +Computer-related introductions in 1986 +Products introduced in 1986 +Products and services discontinued in 1992 +1980s toys +65xx-based video game consoles +Discontinued video game consoles +The Atari Jaguar is a home video game console developed by Atari Corporation and released in North America in November 1993. Part of the fifth generation of video game consoles, it competed with the 16-bit Sega Genesis, the Super NES and the 32-bit 3DO Interactive Multiplayer that launched the same year. Powered by two custom 32-bit Tom and in addition to a Motorola 68000, Atari marketed it as the world's first 64-bit game system, emphasizing its 64-bit bus used by the blitter. The Jaguar launched with Cybermorph as the pack-in game, which received divisive reviews. The system's library ultimately comprised only 50 licensed games. + +Development of the Atari Jaguar started in the early 1990s by Flare Technology, which focused on the system after cancellation of the Atari Panther console. The Jaguar was an important system for Atari after the company shifted its focus from computers - having ceased development of its Atari ST - back to consoles. However, the multi-chip architecture, hardware bugs, and poor tools made writing games for the Jaguar difficult. Underwhelming sales further eroded the console's third-party support. + +Atari attempted to extend the lifespan of the system with the Atari Jaguar CD add-on, with an additional 13 games, and emphasizing the Jaguar's price of over less than its competitors. With the release of the Sega Saturn and PlayStation in 1995, sales of the Jaguar continued to fall. It sold no more than 150,000 units before it was discontinued in 1996. The commercial failure of the Jaguar prompted Atari to leave the console market. + +After Hasbro Interactive acquired all Atari Corporation properties, the patents of the Jaguar were released into the public domain, with the console declared an open platform. Since its discontinuation, hobbyists have produced games for the system. + +History + +Development +Atari Corporation's previous home video game console, the Atari 7800, was released in 1986. While it sold 3.77 million units in the U.S. in the period to 1990, it was considered an 'also-ran' and far behind rival Nintendo. Around 1989 work began on a new console leveraging technology from their Atari ST computers. Originally named the Super XE - following the Atari XE Game System - it eventually became the Atari Panther using either 16 or 32-bit architecture. A more advanced system codenamed Jaguar also began work. + +Both the Jaguar and Panther were developed by the members of Flare Technology, a company formed by Martin Brennan and John Mathieson. The team had claimed that they could not only make a console superior to the Genesis or the Super NES, but they could also be cost-effective. Impressed by their work on the Konix Multisystem, Atari persuaded them to close Flare and form a new company called Flare II, with Atari providing the funding. + +Work on the Jaguar design progressed faster than expected, so Atari canceled the Panther project in 1991 to focus on the more promising Jaguar, and rumors were already circulating of a 1992 launch and its 32-bit or even 64-bit architecture. By this time the Atari ST had long been surpassed in popularity by the Amiga, while both Atari and Commodore became victims of 'Wintel', which would become the dominant computer platform. Support for Atari's legacy 8-bit products were dropped to fully focus on developing the Jaguar console, while their line of ST computers were dropped during the Jaguar's release in 1993. + +The Atari Jaguar was unveiled in at the Summer Consumer Electronics Show in June 1993, calling it a "multi-media entertainment system". + +Launch +The Jaguar was launched on November 23, 1993, at a price of $249.99, under a $500 million manufacturing deal with IBM. The system was initially available only in the test markets of New York City and San Francisco, with the slogan "Get bit by Jaguar", claiming superiority over competing 16-bit and 32-bit systems. During this test launch Atari sold all units hoping it would rally support for the system. A nationwide release followed six months later, in early 1994. The Jaguar struggled to attain a substantial user base. Atari reported that it had shipped 17,000 units as part of the system's initial test market in 1993. By the end of 1994, it reported that it had sold approximately 100,000 units. + +Computer Gaming World wrote in January 1994 that the Jaguar was "a great machine in search of a developer/customer base", as Atari had to "overcome the stigma of its name (lack of marketing and customer support, as well as poor developer relations in the past)". Atari had "ventured late into third party software support" for the Jaguar while competing console 3DO's "18 month public relations blitz" would result in "an avalanche of software support", the magazine reported. The small size and poor quality of the Jaguar's game library became the most commonly cited reason for the Jaguar's tepid adoption, as early releases like Trevor McFur in the Crescent Galaxy, Raiden, and Evolution: Dino Dudes also received poor reviews, the latter two for failing to take full advantage of the Jaguar's hardware. Jaguar did eventually earn praise with games such as Tempest 2000, Doom, and Wolfenstein 3D. The most successful title during the Jaguar's first year was Alien vs. Predator. However, these occasional successes were seen as insufficient while the Jaguar's competitors were receiving a continual stream of critically acclaimed software; GamePro concluded their rave review of Alien vs. Predator by remarking "If Atari can turn out a dozen more games like AvP, Jaguar owners could truly rest easy and enjoy their purchase." Next Generation commented that "thus far, Atari has spectacularly failed to deliver on the software side, leaving many to question the actual quality and capability of the hardware. With only one or two exceptions – Tempest 2000 is cited most frequently – there have just been no truly great games for the Jaguar up to now." They further noted that while Atari is well known by older gamers, the company had much less overall brand recognition than Sega, Sony, Nintendo, or even The 3DO Company. However, they argued that with its low price point, the Jaguar might still compete if Atari could improve the software situation. + +Bit count controversy +Atari tried to downplay competing consoles by proclaiming the Jaguar was the only "64-bit" system; in its marketing in the American market the company used the tagline do the math!, in reference to the 64 number. This claim is questioned by some, because the Motorola 68000 CPU and the Tom and Jerry coprocessors execute 32-bit instruction sets. Atari's reasoning that the 32-bit Tom and Jerry chips work in tandem to add up to a 64-bit system was ridiculed in a mini-editorial by Electronic Gaming Monthly, which commented that "If Sega did the math for the Sega Saturn the way Atari did the math for their 64-bit Jaguar system, the Sega Saturn would be a 112-bit monster of a machine." Next Generation, while giving a mostly negative review of the Jaguar, maintained that it is a true 64-bit system, since the data path from the DRAM to the CPU and Tom and Jerry chips is 64 bits wide. + +Arrival of Saturn and PlayStation +In early 1995, Atari announced that they had dropped the price of the Jaguar to $149.99, in order to be more competitive. Atari ran infomercials with enthusiastic salesmen touting the game system. These aired for most of 1995, but did not sell the remaining stock of Jaguar systems. + +In a 1995 interview with Next Generation, then-CEO Sam Tramiel declared that the Jaguar was as powerful, if not more powerful, than the newly launched Sega Saturn, and slightly weaker than the upcoming PlayStation. Next Generation received a deluge of letters in response to Tramiel's comments, particularly his threat to bring Sony to court for price dumping if the PlayStation entered the U.S. market at a retail price below $300. Many readers found this threat hollow and hypocritical, since Tramiel noted in the same interview that Atari was selling the Jaguar at a loss. The editor responded that price dumping does not have to do with a product being priced below cost, but its being priced much lower in one country than anotherwhich, as Tramiel said, is illegal. Tramiel and Next Generation agreed that the PlayStation's Japanese price converts to approximately $500. His remark, that the small number of third party Jaguar games was good for Atari's profitability, angered Jaguar owners who were already frustrated at how few games were coming out for the system. + +In Atari's 1995 annual report, it noted: In addition, Atari had severely limited financial resources, and so could not create the level of marketing which has historically backed successful gaming consoles. + +Decline +By November 1995, mass layoffs and insider statements were fueling journalistic speculation that Atari had ceased both development and manufacturing for the Jaguar and was simply trying to sell off existing stock before exiting the video game industry. Although Atari continued to deny these theories going into 1996, core Jaguar developers such as High Voltage Software and Beyond Games stated that they were no longer receiving communications from Atari regarding future Jaguar projects. + +In its 10-K405 SEC Filing, filed April 12, 1996, Atari informed stockholders that its revenues had declined by more than half, from $38.7 million in 1994 to $14.6 million in 1995, then gave them the news on the truly dire nature of the Jaguar: + +The filing confirmed that Atari had abandoned the Jaguar in November 1995 and in the subsequent months were concerned chiefly with liquidating its inventory of Jaguar products. On April 8, 1996, Atari Corporation agreed to merge with JTS, Inc. in a reverse takeover, thus forming JTS Corporation. The merger was finalized on July 30. + +After the merger, the bulk of Jaguar inventory remained unsold and would be finally moved out to Tiger Software, a private liquidator, on December 23, 1996. On March 13, 1998, JTS sold the Atari name and all of the Atari properties to Hasbro Interactive. + +Technical specifications +From the Jaguar Software Reference manual, page 1: + +Design specs for the console allude to the GPU or DSP being capable of acting as a CPU, leaving the Motorola 68000 to read controller inputs. Atari's Leonard Tramiel also specifically suggested that the 68000 not be used by developers. In practice, however, many developers use the Motorola 68000 to drive gameplay logic due to the greater developer familiarity of the 68000 and the adequacy of the 68000 for certain types of games. Most critically, a flaw in the memory controller means that certain obscure conventions must be followed for the RISC chips to be able to execute code from RAM. + +The system was notoriously difficult to program for, not only because of its two-processor design but development tools were released in an unfinished state and the hardware had crippling bugs. + +Processors + Tom chip, 26.59 MHz + Graphics processing unit (GPU) – 32-bit RISC architecture, 4 KB internal RAM, all graphical effects are software-based, with additional instructions intended for 3D operations + Object Processor – 64-bit fixed-function video processor, converts display lists to video output at scan time. + Blitter – 64-bit high speed logic operations, z-buffering and Gouraud shading, with 64-bit internal registers. + DRAM controller, 8-, 16-, 32- and 64-bit memory management + Jerry chip, 26.59 MHz + Digital Signal Processor – 32-bit RISC architecture, 8 KB internal RAM + Similar RISC core as the GPU, additional instructions intended for audio operations + CD-quality sound (16-bit stereo) + Number of sound channels limited by software + Two DACs (stereo) convert digital data to analog sound signals + Full stereo capabilities + Wavetable synthesis and AM synthesis + A clock control block, incorporating timers, and a UART + Joystick control + Motorola 68000 - system processor "used as a manager". + General purpose 16-/32-bit control processor, 13.295 MHz + +Other features + + RAM: 2 MB on a 64-bit bus using 4 16-bit fast-page-mode DRAMs (80 ns) + Storage: ROM cartridges – up to 6 MB + DSP-port (JagLink) + Monitor-port (composite/S-Video/RGB) + Antenna-port (UHF/VHF) - fixed at 591 MHz in Europe; not present on French model + Support for ComLynx I/O + NTSC/PAL machines can be identified by their power LED colour, Red: NTSC; Green: PAL. + +COJAG arcade games + +Atari Games licensed the Atari Jaguar's chipset for use in its arcade games. The system, named COJAG (for "Coin-Op Jaguar"), replaced the 68000 with a 68020 or MIPS R3000-based CPU (depending on the board version), added more RAM, a full 64-bit wide ROM bus (Jaguar ROM bus being 32-bit), and optionally a hard drive (some games such as Freeze are ROM only). It runs the lightgun games Area 51 and Maximum Force, which were released by Atari as dedicated cabinets or as the Area 51 and Maximum Force combo machine. Other games were developed but never released: 3 On 3 Basketball, Fishin' Frenzy, Freeze, and Vicious Circle. + +Peripherals + +Prior to the launch of the console in November 1993, Atari had announced a variety of peripherals to be released over the console's lifespan. This included a CD-ROM-based console, a dial-up Internet link with support for online gaming, a virtual reality headset, and an MPEG-2 video card. However, due to the poor sales and eventual commercial failure of the Jaguar, most of the peripherals in development were canceled. The only peripherals and add-ons released by Atari for the Jaguar are a redesigned controller, an adapter for four players, a CD console add-on, and a link cable for local area network (LAN) gaming. + +The redesigned second controller, the ProController by Atari, added three more face buttons and two triggers. It was created in response to the criticism of the original controller, said to lack enough buttons for fighting games in particular. Sold independently, however, it was never bundled with the system. The Team Tap multitap adds 4-controller support, compatible only with the optionally bundled White Men Can't Jump and NBA Jam Tournament Edition. Eight player gameplay with two Team Taps is possible but unsupported by those games. For LAN multiplayer support, the Jaglink Interface links two Jaguar consoles through a modular extension and a UTP phone cable. It is compatible with three games: AirCars, BattleSphere, and Doom. + +In 1994 at the CES, Atari announced that it had partnered with Phylon, Inc. to create the Jaguar Voice/Data Communicator. The unit was delayed and an estimated 100 units were produced, but eventually in 1995 was canceled. The Jaguar Voice Modem or JVM utilizes a 19.9 kbit/s dial up modem to answer incoming phone calls and store up to 18 phone numbers. Players directly dial each other for online play, only compatible with Ultra Vortek which initializes the modem by entering 911 on the key pad at startup. + +Jaguar CD + +The Jaguar CD is a CD-ROM peripheral for games. It was released in September 1995, two years after the Jaguar's launch. Thirteen CD games were released during its manufacturing lifetime, with more being made later by homebrew developers. Each Jaguar CD unit has a Virtual Light Machine, which displays light patterns corresponding to music, if the user inserts an audio CD into the console. It was developed by Jeff Minter, after experimenting with graphics during the development of Tempest 2000. The program was deemed a spiritual successor to the Atari Video Music, a visualizer released in 1976. + +The Memory Track is a cartridge accessory for the Jaguar CD, providing Jaguar CD games with 128 K EEPROM for persistent storage of data such as preferences and saved games. The Atari Jaguar Duo (codenamed Jaguar III) was a proposal to integrate the Jaguar CD to make a new console, a concept similar to the TurboDuo and Genesis CDX. A prototype, described by journalists as resembling a bathroom scale, was unveiled at the 1995 Winter Consumer Electronics Show, but the console was canceled before production. + +Jaguar VR +A virtual reality headset compatible with the console, tentatively titled the Jaguar VR, was unveiled by Atari at the 1995 Winter Consumer Electronics Show. The development of the peripheral was a response to Nintendo's virtual reality console, the Virtual Boy, which had been announced the previous year. The headset was developed in cooperation with Virtuality, which had previously created many virtual reality arcade systems, and was already developing a similar headset for practical purposes, named Project Elysium, for IBM. The peripheral was targeted for a commercial release before Christmas 1995. However, the deal with Virtuality was abandoned in October 1995. After Atari's merger with JTS in 1996, all prototypes of the headset were allegedly destroyed. However, two working units, one low-resolution prototype with red and grey-colored graphics and one high-resolution prototype with blue and grey-colored graphics, have since been recovered, and are regularly showcased at retrogaming-themed conventions and festivals. Only one game was developed for the Jaguar VR prototype: a 3D-rendered version of the 1980 arcade game Missile Command, titled Missile Command 3D, and a demo of Virtuality's Zone Hunter was created. + +Unlicensed peripherals +An unofficial expansion peripheral for the Atari Jaguar dubbed the "Catbox" was released by the Rockford, Illinois company ICD. It was originally slated to be released early in the Jaguar's life, in the second quarter of 1994, but was not actually released until mid-1995. The ICD CatBox plugs directly into the AV/DSP connectors located in the rear of the Jaguar console and provides three main functions. These are audio, video, and communications. It features six output formats, three for audio (line level stereo, RGB monitor, headphone jack with volume control) and three for video (composite, S-Video, and RGB analog component video) making the Jaguar compatible with multiple high quality monitor systems and multiple monitors at the same time. It is capable of communications methods known as CatNet and RS-232 as well as DSP pass through, allowing the user to connect two or more Jaguars together for multiplayer games either directly or with modems. The ICD CatBox features a polished stainless steel casing and red LEDs in the jaguar's eyes on the logo that indicate communications activity. An IBM AT-type null modem cable may be used to connect two Jaguars together. The CatBox is also compatible with Atari's Jaglink Interface peripheral. + +An adaptor for the Jaguar that allows for WebTV access was revealed in 1998; one prototype is known to exist. + +Game library + +Reception + +Reviewing the Jaguar just a few weeks prior to its launch, GamePro gave it a "thumbs sideways". They praised the power of the hardware but criticized the controller, and were dubious of how the software lineup would turn out, commenting that Atari's failure to secure support from key third party publishers such as Capcom was a bad sign. They concluded that "Like the 3DO, the Jaguar is a risky investment – just not quite as expensive." + +The Jaguar won GameFan'''s "Best New System" award for 1993. + +The small size and poor quality of the Jaguar's game library became the most commonly cited reason for its failure in the marketplace. The pack-in game Cybermorph was one of the first polygon-based games for consoles, but was criticized for design flaws and a weak color palette, and compared unfavorably with the SNES's Star Fox. Other early releases like Trevor McFur in the Crescent Galaxy, Raiden, and Evolution: Dino Dudes also received poor reviews, the latter two for failing to take full advantage of the Jaguar's hardware. Jaguar did eventually earn praise with games such as Tempest 2000, Doom, and Wolfenstein 3D. The most successful title during the Jaguar's first year was Alien vs. Predator. However, these occasional successes were seen as insufficient while the Jaguar's competitors were receiving a continual stream of critically acclaimed software; GamePro concluded their rave review of Alien vs. Predator by remarking "If Atari can turn out a dozen more games like AvP, Jaguar owners could truly rest easy and enjoy their purchase." In late 1995 reviews of the Jaguar, Game Players remarked, "The Jaguar suffers from several problems, most importantly the lack of good software." and Next Generation likewise commented that "thus far, Atari has spectacularly failed to deliver on the software side, leaving many to question the actual quality and capability of the hardware. With only one or two exceptions – Tempest 2000 is cited most frequently – there have just been no truly great games for the Jaguar up to now." They further noted that while Atari is well known by older gamers, the company had much less overall brand recognition than Sega, Sony, Nintendo, or even The 3DO Company. However, they argued that with its low price point, the Jaguar might still compete if Atari could improve the software situation. They gave the system two out of five stars. Game Players also stated the despite being 64-bit, the Jaguar is much less powerful than the 3DO, Saturn, and PlayStation, even when supplemented with the Jaguar CD. With such a small library of games to challenge the incumbent 16-bit game consoles, Jaguar's appeal never grew beyond a small gaming audience. Digital Spy commented: "Like many failed hardware ventures, it still maintains something of a cult following but can only be considered a misstep for Atari." + +In 2006 IGN editor Craig Harris rated the original Jaguar controller as the worst game controller ever, criticizing the unwarranted recycling of the 1980s "phone keypad" format and the small number of action buttons, which he found particularly unwise given that Atari was actively trying to court fighting game fans to the system. Ed Semrad of Electronic Gaming Monthly commented that many Jaguar games gratuitously used all of the controller's phone keypad buttons, making the controls much more difficult than they needed to be. GamePros The Watch Dog remarked, "The controller usually doesn't use the keypad, and for games that use the keypad extensively (Alien vs. Predator, Doom), a keypad overlay is used to minimize confusion. But yes, it is a lot of buttons for nuttin'." Atari added more action buttons for its Pro Controller, to improve performance in fighting games in particular. + +Legacy + +Telegames continued to publish games for the Jaguar after it was discontinued, and for a time was the only company to do so. On May 14, 1999, Hasbro Interactive announced that it had released all patents to the Jaguar, declaring it an open platform; this opened the doors for extensive homebrew development. Following the announcement, Songbird Productions joined Telegames in releasing unfinished Jaguar games alongside new games to satisfy the cult following. Hasbro Interactive, along with all the Atari properties, was sold to Infogrames on January 29, 2001. + +In the United Kingdom in 2001, Telegames and retailer Game made a deal to bring the Jaguar to Game's retail outlets. It was initially sold for £29.99 new and software ranged between £9.99 for more common games such as Doom and Ruiner Pinball and £39.99 for rarer releases such as Defender 2000 and Checkered Flag. The machine had a presence in the stores until 2007, when remaining consoles were sold off for £9.99 and games were sold for as low as 97p. + +Molds +In 1997, Imagin Systems, a manufacturer of dental imaging equipment, purchased the Jaguar cartridge and console molds, including the molds for the CD add-on, from JTS. The console molds could, with minor modification, fit their HotRod camera, and the cartridge molds were reused to create an optional memory expansion card. In a retrospective, Imagin founder Steve Mortenson praised the design, but admitted that their device came at the time of the dental industry's transition to USB, and apart from a few prototypes, the molds went unused. + +In December 2014, the molds were purchased from Imagin Systems by Mike Kennedy, owner of the Kickstarter funded Retro Videogame Magazine'', to propose a new crowdfunded video game console, the Retro VGS, later rebranded the Coleco Chameleon after entering a licensing agreement with Coleco. The purchase of the molds was far cheaper than designing and manufacturing entirely new molds, and Kennedy described their acquisition as "the entire reason [the Retro VGS] is possible". However, the project was terminated in March 2016 following criticism of Kennedy and doubts regarding demand for the proposed console. Two "prototypes" were discovered to be fakes and Coleco withdrew from the project. After the project's termination, the molds were sold to Albert Yarusso, the founder of the AtariAge website. + +See also + Contiki, portable operating system, including a port for the Jaguar with GUI, TCP/IP, and web browser support. + +References + +External links + + + Atari Jaguar review, 1994 + +Products introduced in 1993 +Products and services discontinued in 1996 +Jaguar duo +Home video game consoles +Fifth-generation video game consoles +1990s toys +68k-based game consoles +Discontinued video game consoles + Regionless game consoles +The Atari Lynx is a hybrid 8/16-bit fourth-generation hand-held game console released by Atari Corporation in September 1989 in North America and 1990 in Europe and Japan. It was the first handheld game console with a color liquid-crystal display. Powered by a 16 MHz 65C02 8-bit CPU and a custom 16-bit blitter, the Lynx was more advanced than Nintendo's monochrome Game Boy, released two months earlier. It also competed with Sega's Game Gear and NEC's TurboExpress, released the following year. + +The system was developed at Epyx by two former designers of the Amiga personal computers. The project was called the Handy Game or simply Handy. In 1991, Atari replaced the Lynx with a smaller model internally referred to as the Lynx II. Atari published a total of 73 games for the Lynx before it was discontinued in 1995. + +History +The Lynx system was originally developed by Epyx as the Handy Game. In 1986, two former Amiga designers, R. J. Mical and Dave Needle, had been asked by a former manager at Amiga, David Morse, to design a portable gaming system. Morse now worked at Epyx, a game software company with a recent string of hit games. Morse's son had asked him if he could make a portable gaming system, prompting a meeting with Mical and Needle to discuss the idea. Morse convinced Mical and Needle and they were hired by Epyx to be a part of the design team. Planning and design of the console began in 1986 and was completed in 1987. Epyx first showed the Handy system at the Winter Consumer Electronics Show (CES) in January 1989. Facing financial difficulties, Epyx sought partners. Nintendo, Sega, and other companies declined, but Atari and Epyx eventually agreed that Atari would handle production and marketing, and Epyx would handle software development. Epyx declared bankruptcy by the end of the year, so Atari essentially owned the entire project. Both Atari and others had to purchase Amigas from Atari arch-rival Commodore in order to develop Lynx software. + +The Handy was designed to run games from the cartridge format, and the game data must be copied from ROM to RAM before it can be used. Thus, less RAM is then available and each game's initial loading is slow. There are trace remnants of a cassette tape interface physically capable of being programmed to read a tape. Lynx developers have noted that "there is still reference of the tape and some hardware addresses" and an updated vintage Epyx manual describes the bare existence of what could be utilized for tape support. A 2009 retrospective interview with Mical clarifies that there is no truth to some early reports claiming that games were loaded from tape, and elaborates, "We did think about hard disk a little." + +The networking system was originally developed to run over infrared links and codenamed RedEye. This was changed to a cable-based networking system before the final release as the infrared beam was too easily interrupted when players walked through the beam, according to Peter Engelbrite. Engelbrite developed the first recordable eight-player co-op game, and the only eight-player game for the Lynx, Todd's Adventures in Slime World. + +Atari changed the internal speaker and removed the thumb stick on the control pad. At Summer 1989 CES, Atari's press demonstration included the "Portable Color Entertainment System", which was changed to "Lynx" when distributed to resellers, initially retailing in the US at . + +Its launch was successful. Atari reported that it had sold 90% of the 50,000 units shipped in the launch month in the U.S. with a limited launch in New York. US sales in 1990 were approximately 500,000 units according to the Associated Press. In late 1991, it was reported that Atari sales estimates were about 800,000, which Atari claimed was within its expected projections. Lifetime sales by 1995 amount to fewer than 7 million units when combined with the Game Gear. In comparison, 16 million Game Boy units were sold by 1995 because of its ruggedness, half price, much longer battery life, bundling with the smash hit Tetris, and superior game library. + +As with the console units, the game cartridge design evolved over the first year of the console's release. The first generation of cartridges are flat, and designed to be stackable for ease of storage. However, this design proved to be very difficult to remove from the console and was replaced by a second design. This style, called "tabbed" or "ridged", adds two small tabs on the underside to aid in removal. The original flat style cartridges can be stacked on top of the newer cartridges, but the newer cartridges can not be easily stacked on each other, nor were they stored easily. Thus a third style, the "curved lip" style was produced, and all official and third-party cartridges during the console's lifespan were released (or re-released) using this style. + +In May 1991, Sega launched its Game Gear portable gaming handheld with a color screen. In comparison to the Lynx it had shorter battery life (3–4 hours as opposed to 4-5 for the Lynx), but it is slightly smaller, has significantly more games, and cost $30 less than the Lynx at launch. + +Retailers such as Game and Toys "R" Us continued to sell the Lynx well into the mid-1990s on the back of the Atari Jaguar launch, helped by magazines such as Ultimate Future Games which continued to cover the Lynx alongside the new generation of 32-bit and 64-bit consoles. + +Lynx II + +In July 1991, Atari introduced a new version of the Lynx, internally called the "Lynx II", with a new marketing campaign, new packaging, slightly improved hardware, better battery life, and a sleeker look. It has rubber hand grips and a clearer backlit color screen with a power save option (which turns off the backlighting). The monaural headphone jack of the original Lynx was replaced with one wired for stereo. The Lynx II was available without any accessories, dropping the price to . + +Decline + +In 1993, Atari started shifting its focus away from the Lynx in order to prepare for the launch of the Jaguar; a few games were released during that time, including Battlezone 2000. Support for the Lynx was formally discontinued in 1995. + +After the respective launches of the Sega Saturn and Sony PlayStation caused the commercial failure of the Jaguar, Atari ceased all game development and hardware manufacturing by early 1996 and would later merge with JTS, Inc. on July 30 of that year. + +Features +The Atari Lynx has a backlit color LCD display, switchable right- and left-handed (upside down) configuration, and the ability to network with other units via Comlynx cable. The maximum stable connection allowed is eight players. Each Lynx needs a copy of the game, and one cable can connect two machines. The cables can be connected into a chain. + +The Lynx was cited as the "first gaming console with hardware support for zooming and distortion of sprites". With a 4096 color palette and integrated math and graphics co-processors (including a sprite engine unit), its color graphics display was said to be the key defining feature in the system's competition against Nintendo's monochromatic Game Boy. The fast pseudo-3D graphics features were made possible on a minimal hardware system by co-designer Dave Needle having "invented the technique for planar expansion/shrinking capability" and using stretched, textured, triangles instead of full polygons. + +Technical specifications + + Mikey (8-bit VLSI custom CMOS chip running at 16 MHz) + VLSI 8-bit VL65NC02 processor (based on the MOS 6502) running at up to 4 MHz (3.6 MHz average) + Sound engine + 4 channel sound + 8-bit DAC for each channel (4 channels × 8-bits/channel = 32 bits commonly quoted) these four sound channels can also switch in analogue sound mode to generate PSG sound. + Video DMA driver for liquid-crystal display + Custom built and designed by Jay Miner and David Morse + 160×102 pixels resolution + 4,096 color (12-bit) palette + 16 simultaneous colors (4 bits) from palette per scanline + Variable frame rate (up to 75 frames/second) + Eight system timers (two reserved for LCD timing, one for UART) + Interrupt controller + UART (for Comlynx) (fixed format 8E1, up to 62500 Bd / TurboMode 1,000,000Bd) + 512 bytes of bootstrap and game-card loading ROM + Suzy (16-bit VLSI custom CMOS chip running at ) + Unlimited number of blitter "sprites" with collision detection + Hardware sprite scaling, distortion, and tilting effects + Hardware decoding of compressed sprite data + Hardware clipping and multi-directional scrolling + Math engine + Hardware 16-bit × 16-bit → 32-bit multiply with optional accumulation; 32-bit ÷ 16-bit → 16-bit divide + Parallel processing of CPU + RAM: 64 KB 120ns DRAM + Cartridges: 128, 256, 512 KB and (with bank-switching) 1 MB + Ports: + Headphone port ( stereo; wired for mono on the original Lynx) + ComLynx (multiple unit communications, serial) + LCD Screen: 3.5" diagonal + Battery holder (six AA) 4–5 hours (Lynx I) 5–6 hours (Lynx II) + +Reception + +Lynx was reviewed in 1990 in Dragon, which gave it 5 out of 5 stars. The review states that the Lynx "throws the Game Boy into the prehistoric age", and praises the built-in object scaling capabilities, the multiplayer feature of the ComLynx cable, and the strong set of launch games. + +Legacy +Telegames released several games in the late 1990s, including a port of Raiden and a platformer called Fat Bobby in 1997, and an action sports game called Hyperdrome in 1999. + +On March 13, 1998, nearly three years after the Lynx's discontinuation, JTS Corporation sold all of the Atari assets to Hasbro Interactive for $5 million. On May 14, 1999, Hasbro, which held on to those properties until selling Hasbro Interactive to Infogrames in 2001, released into the public domain all rights to the Jaguar, opening up the platform for anyone to publish software on without Hasbro's interference. Internet theories say that the Lynx's rights may have been released to the public at the same time as the Jaguar, but this is clearly disputed. Nevertheless, since discontinuation, the Lynx, like the Jaguar, has continued to receive support from a grassroots community which would go on to produce many successful homebrew games such as T-Tris (the first Lynx game with a save-game feature), Alpine Games, and Zaku. + +In 2008, Atari was honored at the 59th Annual Technology & Engineering Emmy Awards for pioneering the development of handheld games with the Lynx. + +See also + List of Atari Lynx games + History of Atari + +References + +External links + + AtariAge – Comprehensive Lynx Database and information + Guide to Atari Lynx games at Retro Video Gamer + Too Powerful for Its Own Good, Atari's Lynx Remains a Favorite 25 Years Later + Atari Lynx review, 1990 + Atari Lynx Hardware Documentation + Atari Lynx Development Wiki + +Computer-related introductions in 1989 +Discontinued handheld game consoles +Handheld game consoles +Fourth-generation video game consoles +Lynx +1980s toys +1990s toys +65xx-based video game consoles +Public domain in the United States +Regionless game consoles +(, IAST: , ) is the ancient Indian principle of nonviolence which applies to actions towards all living beings. It is a key virtue in Indian religions like Jainism, Buddhism, Hinduism, and Sikhism. + + is one of the cardinal virtues of Jainism, where it is the first of the Pancha Mahavrata. It is also one of the central precepts of Hinduism and is the first of the five precepts of Buddhism. is inspired by the premise that all living beings have the spark of the divine spiritual energy; therefore, to hurt another being is to hurt oneself. + is also related to the notion that all acts of violence have karmic consequences. While ancient scholars of Brahmanism had already investigated and refined the principles of +, the concept reached an extraordinary development in the ethical philosophy of Jainism. Mahavira, the twenty-fourth and the last of Jainism, further strengthened the idea in . About , Thiruvalluvar emphasized and moral vegetarianism as virtues for an individual, which formed the core of his teachings. Perhaps the most popular advocate of the principle of in modern times was Mahatma Gandhi. + +'s precept that humans should 'cause no injury' to another living being includes one's deeds, words, and thoughts. Classical Hindu texts like the Mahabharata and the Ramayana, as well as modern scholars, disagree about what the principle of dictates when one is faced with war and other situations that require self-defence. In this way, historical Indian literature has contributed to modern theories of just war and self-defence. + +Etymology +The word —sometimes spelled —is derived from the Sanskrit root , meaning to strike; is injury or harm, while (prefixed with the alpha privative), its opposite, is non-harming or nonviolence. + +Origins +Reverence for can be found in Hindu, Jain, and Buddhist canonical texts. Parshvanatha is said to have preached as one of the four vows. No other Indian religion has developed the non-violence doctrine and its implications on everyday life as much as has Jainism. + +Hinduism + +Ancient Vedic texts + as an ethical concept evolved in the Vedic texts. The oldest scriptures indirectly mention . Over time, the Hindu scripts revised ritual practices, and the concept of was increasingly refined and emphasized until became the highest virtue by the late Vedic era (about ). For example, hymn 10.22.25 in the Rig Veda uses the words (truthfulness) and in a prayer to deity Indra; later, the Yajur Veda dated to be between and , states, "may all beings look at me with a friendly eye, may I do likewise, and may we look at each other with the eyes of a friend". + +The term appears in the text Taittiriya Shakha of the Yajurveda (TS 5.2.8.7), where it refers to non-injury to the sacrificer himself. It occurs several times in the Shatapatha Brahmana in the sense of "non-injury". The doctrine is a late Vedic era development in Brahmanical culture. The earliest reference to the idea of non-violence to animals (), apparently in a moral sense, is in the Kapisthala Katha Samhita of the Yajurveda (KapS 31.11), which may have been written in about . + +John Bowker states the word appears but is uncommon in the principal Upanishads. Kaneda gives examples of the word in these Upanishads. Other scholars suggest as an ethical concept started evolving in the Vedas, becoming an increasingly central concept in Upanishads. + +The Chāndogya Upaniṣad, dated to , one of the oldest Upanishads, has the earliest evidence for the Vedic era use of the word in the sense familiar in Hinduism (a code of conduct). It bars violence against "all creatures" (), and the practitioner of is said to escape from the cycle of rebirths (CU 8.15.1). Some scholars state that this mention may have been an influence of Jainism on Vedic Hinduism. Others scholar state that this relationship is speculative, and though Jainism is an ancient tradition the oldest traceable texts of Jainism tradition are from many centuries after the Vedic era ended. + +Chāndogya Upaniṣad also names , along with (truthfulness), (sincerity), (charity), and (penance/meditation), as one of five essential virtues (CU 3.17.4). + +The Sandilya Upanishad lists ten forbearances: , , , , , , , , , and . According to Kaneda, the term is an important spiritual doctrine shared by Hinduism, Buddhism, and Jainism. It means 'non-injury' and 'non-killing'. It implies the total avoidance of harming any living creature by deeds, words, and thoughts. + +The Epics +The Mahabharata, one of the epics of Hinduism, has multiple mentions of the phrase (), which literally means: non-violence is the highest moral virtue. For example, Anushasana Parva has the verse: + +The above passage from Mahabharata emphasises the cardinal importance of in Hinduism, and literally means: + is the highest , is the highest self-control, + is the greatest gift, is the best practice, + is the highest sacrifice, is the finest strength, + is the greatest friend, is the greatest happiness, + is the highest truth, and is the greatest teaching. +Some other examples where the phrase are discussed include Adi Parva, Vana Parva, and Anushasana Parva. The Bhagavad Gita, among other things, discusses the doubts and questions about appropriate response when one faces systematic violence or war. These verses develop the concepts of lawful violence in self-defence and the theories of just war. However, there is no consensus on this interpretation. Gandhi, for example, considers this debate about non-violence and lawful violence as a mere metaphor for the internal war within each human being, when he or she faces moral questions. + +Self-defence, criminal law, and war +The classical texts of Hinduism devote numerous chapters to discussing what people who practice the virtue of can and must do when faced with war, violent threat, or the need to sentence someone convicted of a crime. These discussions have led to theories of just war, ideas of reasonable self-defense, and views of proportionate punishment. Arthashastra discusses, among other things, what constitutes proportionate response and punishment. + + War +The precepts of in Hinduism require that war must be avoided, with sincere and truthful dialogue. Force must be the last resort. If war becomes necessary, its cause must be just, its purpose virtuous, its objective to restrain the wicked, its aim peace, and its method lawful. War can only be started and stopped by a legitimate authority. Weapons must be proportionate to the opponent and the aim of war, not indiscriminate tools of destruction. All strategies and weapons used in the war must be to defeat the opponent, not to cause misery to the opponent; for example, the use of arrows is allowed, but the use of arrows smeared with painful poison is not allowed. Warriors must use judgment in the battlefield. Cruelty to the opponent during war is forbidden. Wounded, unarmed opponent warriors must not be attacked or killed; they must be brought to your realm and given medical treatment. Children, women, and civilians must not be injured. While the war is in progress, sincere dialogue for peace must continue. + + Self-defence +Different interpretations of ancient Hindu texts have been offered in matters of self-defense. For example, Tähtinen suggests self-defense is appropriate, criminals are not protected by the rule of , and Hindu scriptures support violence against an armed attacker. is not meant to imply pacifism. + +Alternative theories of self-defense, inspired by , build principles similar to ideas of just war. Aikido, pioneered in Japan, illustrates one such set of principles for self-defense. Morihei Ueshiba, the founder of Aikido, described his inspiration as Ahimsa. According to this interpretation of in self-defense, one must not assume that the world is free of aggression. One must presume that some people will, out of ignorance, error, or fear, attack others or intrude into their space, physically or verbally. The aim of self-defense, suggested Ueshiba, must be to neutralize the attacker's aggression and avoid conflict. The best defense is one with which the victim is protected and the attacker is respected and not injured if possible. Under and Aikido, there are no enemies, and appropriate self-defense focuses on neutralizing the immaturity, assumptions, and aggressive strivings of the attacker. + + Criminal law +Tähtinen concludes that Hindus have no misgivings about the death penalty; their position is that evil-doers who deserve death should be killed and that a king, in particular, is obliged to punish criminals and should not hesitate to kill them, even if they happen to be his brothers and sons. + +Other scholars conclude that Hindu scriptures suggest that sentences for any crime must be fair, proportional, and not cruel. + +Non-human life + +The Hindu precept of "cause no injury" applies to animals and all life forms. This precept is not found in the oldest verses of Vedas (), but increasingly becomes one of the central ideas in post-Vedic period. In the oldest layer of the Vedas, such as the Rigveda, ritual sacrifices of animals and cooking of meat to feed guests are mentioned. This included goat, ox, horse, and others. However, the text is not uniform in its prescriptions. Some verses praise meat as food, while other verses in the Vedas recommend "abstention from meat", in particular, "beef". According to Marvin Harris, the Vedic literature is inconsistent, with some verses suggesting ritual slaughter and meat consumption, while others suggesting a taboo on meat-eating. + +Hindu texts dated to initially mention meat as food, then evolve to suggest that only meat obtained through ritual sacrifice can be eaten, thereafter evolving to the stance that one should eat no meat because it hurts animals, with verses describing the noble life as one that lives on flowers, roots, and fruits alone. The late Vedic-era literature () condemns all killings of men, cattle, birds, and horses, and prays to god Agni to punish those who kill. + +Later texts of Hinduism declare one of the primary virtues, declare any killing or harming any life as against (moral life). Finally, the discussion in Upanishads and Hindu Epics shifts to whether a human being can ever live his or her life without harming animal and plant life in some way, which and when plants or animal meat may be eaten, whether violence against animals causes human beings to become less compassionate, and if and how one may exert least harm to non-human life consistent with , given the constraints of life and human needs. The Mahabharata permits hunting by warriors, but opposes it in the case of hermits who must be strictly non-violent. Sushruta Samhita, a Hindu text written in , in Chapter XLVI suggests proper diet as a means of treating certain illnesses, and recommends various fishes and meats for different ailments and for pregnant women, and the Charaka Samhita describes meat as superior to all other kinds of food for convalescents. + +Across the texts of Hinduism, there is a profusion of ideas about the virtue of when applied to non-human life, but without a universal consensus. Alsdorf claims the debate and disagreements between supporters of vegetarian lifestyle and meat eaters was significant. Even suggested exceptions – ritual slaughter and hunting – were challenged by advocates of . In the Mahabharata both sides present various arguments to substantiate their viewpoints. Moreover, a hunter defends his profession in a long discourse. + +Many of the arguments proposed in favor of non-violence to animals refer to the bliss one feels, the rewards it entails before or after death, the danger and harm it prevents, as well as to the karmic consequences of violence. + +The ancient Hindu texts discuss and non-animal life. They discourage wanton destruction of nature including of wild and cultivated plants. Hermits (sannyasins) were urged to live on a fruitarian diet so as to avoid the destruction of plants. Scholars claim the principles of ecological nonviolence are innate in the Hindu tradition, and its conceptual fountain has been as its cardinal virtue. + +The classical literature of the Indian religions, such as Hinduism and Jainism, exists in many Indian languages. For example, the Tirukkural, written in three volumes, likely between , dedicates verses 251–260 and 321–333 of its first volume to the virtue of , emphasizing on moral vegetarianism and non-killing (). However, the Tirukkural also glorifies soldiers and their valour during war, and states that it is king's duty to punish criminals and implement "death sentence for the wicked". + +In 1960, H. Jay Dinshah founded the American Vegan Society (AVS), linking veganism to the concept of . + +Modern times + +In the 19th and 20th centuries, prominent figures of Indian spirituality such as Shrimad Rajchandra and Swami Vivekananda emphasised the importance of Ahimsa. + +Mohandas Karamchand Gandhi successfully promoted the principle of to all spheres of life, in particular to politics (). His non-violent resistance movement had an immense impact on India, impressed public opinion in Western countries, and influenced the leaders of various civil and political rights movements such as the American civil rights movement's Martin Luther King Jr. and James Bevel. In Gandhi's thought, precludes not only the act of inflicting a physical injury but also mental states like evil thoughts and hatred, and unkind behavior such as harsh words, dishonesty, and lying, all of which he saw as manifestations of violence incompatible with . Gandhi believed to be a creative energy force, encompassing all interactions leading one's self to find , "Divine Truth". Sri Aurobindo criticized the Gandhian concept of as unrealistic and not universally applicable; he adopted a pragmatic non-pacifist position, saying that the justification of violence depends on the specific circumstances of the given situation. + +Gandhi stated his belief that " is in Hinduism, it is in Christianity as well as in Islam." He added, "Nonviolence is common to all religions, but it has found the highest expression and application in Hinduism (I do not regard Jainism or Buddhism as separate from Hinduism)." When questioned whether violence and nonviolence are taught in Quran, he stated, "I have heard from many Muslim friends that the Koran teaches the use of nonviolence. (... The) the argument about nonviolence in the Holy Koran is an interpolation, not necessary for my thesis." + +Studying 's history and philosophy influenced Albert Schweitzer's principle of "reverence for life." He commended Indian traditions for their ethics of , considering the prohibition against killing and harming "one of the greatest events in the spiritual history of humankind". However, he noted that "not-killing" and "not-harming" might be unfeasible in certain situations, like self-defense, or ethically complex, as in cases of prolonged famine. + +Yoga + is imperative for practitioners of Patañjali's eight limb Raja yoga system. It is included in the first limb and is the first of five (self restraints) which, together with the second limb, make up the code of ethical conduct in Yoga philosophy. is also one of the ten in Hatha Yoga according to verse 1.1.17 of its classic manual Hatha Yoga Pradipika. +The significance of as the first restraint in the first limb of Yoga (), is that it defines the necessary foundation for progress through Yoga. It is a precursor to , implying that success in can be had only if the self is purified in thought, word, and deed through the self-restraint of . + +Jainism + +In Jainism, the understanding and implementation of is more radical, scrupulous, and comprehensive than in any other religion. Killing any living being is considered (to injure) and abstaining from such an act is (noninjury). The vow of is considered the foremost among the "five vows of Jainism". Other vows like truth () are meant for safeguarding the vow of . + +In the practice of , the requirements are less strict for the lay persons () who have undertaken (Smaller Vows) than for the Jain monastics who are bound by the Mahavrata "Great Vows". + +The statement (or, "Non-injury/nonviolence/harmlessness is the supreme/ultimate/paramount/highest/absolute duty/virtue/attribute/religion") is often found inscribed on the walls of the Jain temples. As in Hinduism, the aim is to prevent the accumulation of harmful karma. + +When Mahavira revived and reorganised the Jain faith in , was already an established, strictly observed rule. Rishabhanatha (Ādinātha), the first Jain Tirthankara, whom modern Western historians consider to be a historical figure, followed by Parshvanatha (Pārśvanātha) the twenty-third Tirthankara lived in about . He founded the community to which Mahavira's parents belonged. Ahimsa was already part of the "Fourfold Restraint" (Caujjama), the vows taken by Parshva's followers. In the times of Mahavira and in the following centuries, Jains were at odds with both Buddhists and followers of the Vedic religion or Hindus, whom they accused of negligence and inconsistency in the implementation of . According to the Jain tradition either lacto vegetarianism or veganism is prescribed. + +The Jain concept of is characterised by several aspects. Killing of animals for food is absolutely ruled out. Jains also make considerable efforts not to injure plants in everyday life as far as possible. Though they admit that plants must be destroyed for the sake of food, they accept such violence only inasmuch as it is indispensable for human survival, and there are special instructions for preventing unnecessary violence against plants. Jain monks and nuns go out of their way so as not to hurt even small insects and other minuscule animals. Both the renouncers and the laypeople of Jain faith reject meat, fish, alcohol, and honey as these are believed to harm large or minuscule life forms. + +Jain scholars have debated the potential injury to other life forms during one's occupation. Certain Jain texts (according to Padmannabh Jaini, a Jainism scholar) forbid people of its faith from husbandry, agriculture, and trade in animal-derived products. Some Jains abstain from farming because it inevitably entails unintentional killing or injuring of many small animals, such as worms and insects, These teachings, in part, have led the Jain community to focus on trade, merchant, clerical, and administrative occupations to minimize (occupational violence against all life forms). For the layperson, the teaching has been of with – that is, reducing violence through proper intention and being careful in every action on a daily basis to minimize violence to all life forms. + +The Jain texts, unlike most Hindu and Buddhist texts on just war, have been inconsistent. For its monastic community – and – the historically accepted practice has been to "willingly sacrifice one's own life" to the attacker, to not retaliate, so that the mendicant may keep the First Great Vow of "total nonviolence". Jain literature of , for example, describes a king ready for war and being given lessons about non-violence by the Jain acharya (spiritual teacher). In and thereafter, in an era of violent raids, destruction of temples, the slaughter of agrarian communities and ascetics by Islamic armies, Jain scholars reconsidered the First Great Vow of mendicants and its parallel for the laypeople. The medieval texts of this era, such as by Jinadatta Suri, recommended both the mendicants and the laypeople to fight and kill if that would prevent greater and continued violence on humans and other life forms (). Such exemptions to is a relatively rare teaching in Jain texts, states Dundas. + +Mahatma Gandhi stated, "No religion in the World has explained the principle of so deeply and systematically as is discussed with its applicability in every human life in Jainism. As and when the benevolent principle of or non-violence will be ascribed for practice by the people of the world to achieve their end of life in this world and beyond, Jainism is sure to have the uppermost status and Mahāvīra is sure to be respected as the greatest authority on ". + +Buddhism + +In Buddhist texts (or its Pāli cognate ) is part of the Five Precepts (), the first of which has been to abstain from killing. This precept of is applicable to both the Buddhist layperson and the monk community. + +The precept is not a commandment, and transgressions did not for laypersons, but their power has been in the Buddhist belief in karmic consequences and their impact in afterlife during rebirth. Killing, in Buddhist belief, could lead to rebirth in the hellish realm, and for a longer time in more severe conditions if the murder victim was a monk. Saving animals from slaughter for meat is believed to be a way to acquire merit for better rebirth. These moral precepts have been voluntarily self-enforced in lay Buddhist culture through the associated belief in karma and rebirth. Buddhist texts not only recommend , but suggest avoiding trading goods that contribute to or are a result of violence: + +Unlike with lay Buddhists, transgressions by monks do invite sanctions. Full expulsion of a monk from follows instances of killing, just like any other serious offense against the monastic code of conduct. + +War +Violent ways of punishing criminals and prisoners of war were not explicitly condemned in Buddhism, but peaceful ways of conflict resolution and punishment with the least amount of injury were encouraged. The early texts condemn the mental states that lead to violent behavior. + +Nonviolence is an theme within the Pāli Canon. While the early texts condemn killing in the strongest terms, and portray the ideal queen/king as a pacifist, such a queen/king is nonetheless flanked by an army. It seems that the Buddha's teaching on nonviolence was not interpreted or put into practice in an uncompromisingly pacifist or anti-military-service way by early Buddhists. The early texts assume war to be a fact of life, and well-skilled warriors are viewed as necessary for defensive warfare. In Pali texts, injunctions to abstain from violence and involvement with military affairs are directed at members of the ; later Mahayana texts, which often generalise monastic norms to laity, require this of lay people as well. + +The early texts do not contain just-war ideology as such. Some argue that a in the Gamani Samyuttam rules out all military service. In this passage, a soldier asks the Buddha if it is true that, as he has been told, soldiers slain in battle are reborn in a heavenly realm. The Buddha reluctantly replies that if he is killed in battle while his mind is seized with the intention to kill, he will undergo an unpleasant rebirth. In the early texts, a person's mental state at the time of death is generally viewed as having a great impact on the next birth. + +Some Buddhists point to other early texts as justifying defensive war. One example is the Kosala Samyutta, in which King Pasenadi, a righteous king favored by the Buddha, learns of an impending attack on his kingdom. He arms himself in defence, and leads his army into battle to protect his kingdom from attack. He lost this battle but won the war. King Pasenadi eventually defeated King Ajātasattu and captured him alive. He thought that, although this King of Magadha has transgressed against his kingdom, he had not transgressed against him personally, and Ajātasattu was still his nephew. He released Ajātasattu and did not harm him. Upon his return, the Buddha said (among other things) that Pasenadi "is a friend of virtue, acquainted with virtue, intimate with virtue", while the opposite is said of the aggressor, King Ajātasattu. + +According to Theravada commentaries, there are five requisite factors that must all be fulfilled for an act to be both an act of killing and to be karmically negative. These are: (1) the presence of a living being, human or animal; (2) the knowledge that the being is a living being; (3) the intent to kill; (4) the act of killing by some means; and (5) the resulting death. Some Buddhists have argued on this basis that the act of killing is complicated, and its ethicality is predicated upon intent. Some have argued that in defensive postures, for example, the primary intention of a soldier is not to kill, but to defend against aggression, and the act of killing in that situation would have minimal negative karmic repercussions. + +According to Babasaheb Ambedkar, there is circumstantial evidence encouraging from the Buddha's doctrine, "Love all, so that you may not wish to kill any." Gautama Buddha distinguished between a principle and a rule. He did not make a matter of rule, but suggested it as a matter of principle. This gives Buddhists freedom to act. + +Laws +The emperors of the Sui dynasty, Tang dynasty, and early Song dynasty banned killing in the Lunar calendar's 1st, 5th, and 9th months. Empress Wu Tse-Tien banned killing for more than half a year in 692. Some rulers banned fishing for a period of time each year. + +There were also bans after the death of emperors, after Buddhist and Taoist prayers, and after natural disasters such as Shanghai's 1926 summer drought, as well as an eight-day ban beginning August 12, 1959, after the August 7 flood (八七水災), the last big flood before the 88 Taiwan Flood. + +People avoid killing during some festivals, like the Taoist Ghost Festival, the Nine Emperor Gods Festival, and the Vegetarian Festival, as well as during others. + +See also + +References + +Citations + +Sources + + + + + + + + + + + + + + + + +Attribution: + +External links + + + Series of Lectures on Ahimsa + +Buddhist ethics +Concepts in ethics +Hindu ethics +Hindu philosophical concepts +Jain ethics +Jain philosophical concepts +Pacifism +Sanskrit words and phrases +Wholesome factors in Buddhism +The Annals of Mathematics is a mathematical journal published every two months by Princeton University and the Institute for Advanced Study. + +History + +The journal was established as The Analyst in 1874 and with Joel E. Hendricks as the founding editor-in-chief. It was "intended to afford a medium for the presentation and analysis of any and all questions of interest or importance in pure and applied Mathematics, embracing especially all new and interesting discoveries in theoretical and practical astronomy, mechanical philosophy, and engineering". It was published in Des Moines, Iowa, and was the earliest American mathematics journal to be published continuously for more than a year or two. This incarnation of the journal ceased publication after its tenth year, in 1883, giving as an explanation Hendricks' declining health, but Hendricks made arrangements to have it taken over by new management, and it was continued from March 1884 as the Annals of Mathematics. The new incarnation of the journal was edited by Ormond Stone (University of Virginia). It moved to Harvard in 1899 before reaching its current home in Princeton in 1911. + +An important period for the journal was 1928–1958 with Solomon Lefschetz as editor. During this time, it became an increasingly well-known and respected journal. Its rise, in turn, stimulated American mathematics. Norman Steenrod characterized Lefschetz' impact as editor as follows: "The importance to American mathematicians of a first-class journal is that it sets high standards for them to aim at. In this somewhat indirect manner, Lefschetz profoundly affected the development of mathematics in the United States." + +Princeton University continued to publish the Annals on its own until 1933, when the Institute for Advanced Study took joint editorial control. Since 1998 it has been available in an electronic edition, alongside its regular print edition. The electronic edition was available without charge, as an open access journal, but since 2008 this is no longer the case. Issues from before 2003 were transferred to the non-free JSTOR archive, and articles are not freely available until 5 years after publication. + +Editors +The current () editors of the Annals of Mathematics are Helmut Hofer, Nick Katz, Sergiu Klainerman, Fernando Codá Marques, Assaf Naor, Peter Sarnak and Zoltán Szabó (all but Helmut Hofer from Princeton University, with Hofer being a professor at the Institute for Advanced Study and Peter Sarnak also being a professor there as a second affiliation). + +Abstracting and indexing +The journal is abstracted and indexed in the Science Citation Index, Current Contents/Physical, Chemical & Earth Sciences, and Scopus. According to the Journal Citation Reports, the journal has a 2020 impact factor of 5.246, ranking it third out of 330 journals in the category "Mathematics". + +References + +External links + + +Mathematics journals +Publications established in 1874 +English-language journals +Bimonthly journals +Princeton University publications +Academic journals published by universities and colleges of the United States +1874 establishments in Iowa +Andrei Dmitrievich Sakharov (; 21 May 192114 December 1989) was a Soviet physicist and a Nobel Peace Prize laureate, which he was awarded in 1975 for emphasizing human rights around the world. + +Although he spent his career in physics in the Soviet program of nuclear weapons, overseeing the development of thermonuclear weapons, Sakharov also did fundamental work in understanding particle physics, magnetism, and physical cosmology. Sakharov is mostly known for his political activism for individual freedom, human rights, civil liberties and reforms in Russia, for which he was deemed a dissident and faced persecution from the Soviet establishment. + +In his memory, the Sakharov Prize was established and is awarded annually by the European Parliament for people and organizations dedicated to human rights and freedoms. + +Biography + +Family background and early life + +Andrei Dmitrievich Sakharov was born in Moscow on 21 May 1921, to a Russian family. His father, Dmitri Ivanovich Sakharov, was a physics professor at the Second Moscow State University and an amateur pianist. His grandfather, Ivan, was a lawyer in the former Russian Empire who had displayed respect for social awareness and humanitarian principles (including advocating the abolition of capital punishment). Sakharov's mother, Yekaterina Alekseevna Sofiano, was a daughter of Aleksey Semenovich Sofiano, a general in the Tsarist Russian Army. + +Sakharov's parents and paternal grandmother, Maria Petrovna, largely shaped his personality; his mother and grandmother were members of the Russian Orthodox Church, although his father was a non-believer. When Andrei was about thirteen, he realized that he did not believe in God. However, despite being an atheist, he did believe in a "guiding principle" that transcends the physical laws. + +After schooling, Sakharov studied physics at the Moscow State University in 1938 and, following evacuation in 1941 during the Eastern Front with Germany, he graduated in Aşgabat in Turkmenistan. In 1943, he married Klavdia Alekseyevna Vikhireva, with whom he raised two daughters and a son. Klavdia would later die in 1969. In 1945, he joined the Theoretical Department of Physical Institute of the Russian Academy of Sciences under Igor Tamm in Moscow. In 1947, Sakharov was successful in defending this thesis for the Doctor of Sciences (lit. Doktor Nauk), which covered the topic of nuclear transmutation. + +Soviet program of nuclear weapons + +After World War II, he researched cosmic rays. In mid-1948 he participated in the Soviet atomic bomb project under Igor Kurchatov and Igor Tamm. Sakharov's study group at FIAN in 1948 came up with a second concept in August–September 1948. Adding a shell of natural, unenriched uranium around the deuterium would increase the deuterium concentration at the uranium-deuterium boundary and the overall yield of the device, because the natural uranium would capture neutrons and itself fission as part of the thermonuclear reaction. This idea of a layered fission-fusion-fission bomb led Sakharov to call it the sloika, or layered cake. The first Soviet atomic device was tested on August 29, 1949. After moving to Sarov in 1950, Sakharov played a key role in the development of the first megaton-range Soviet hydrogen bomb using a design known as Sakharov's Third Idea in Russia and the Teller–Ulam design in the United States. Before his Third Idea, Sakharov tried a "layer cake" of alternating layers of fission and fusion fuel. The results were disappointing, yielding no more than a typical fission bomb. However the design was seen to be worth pursuing because deuterium is abundant and uranium is scarce, and he had no idea how powerful the US design was. Sakharov realised that in order to cause the explosion of one side of the fuel to symmetrically compress the fusion fuel, a mirror could be used to reflect the radiation. The details had not been officially declassified in Russia when Sakharov was writing his memoirs, but in the Teller–Ulam design, soft X-rays emitted by the fission bomb were focused onto a cylinder of lithium deuteride to compress it symmetrically. This is called radiation implosion. The Teller–Ulam design also had a secondary fission device inside the fusion cylinder to assist with the compression of the fusion fuel and generate neutrons to convert some of the lithium to tritium, producing a mixture of deuterium and tritium. Sakharov's idea was first tested as RDS-37 in 1955. A larger variation of the same design which Sakharov worked on was the 50 Mt Tsar Bomba of October 1961, which was the most powerful nuclear device ever detonated. + +Sakharov saw "striking parallels" between his fate and those of J. Robert Oppenheimer and Edward Teller in the US. Sakharov believed that in this "tragic confrontation of two outstanding people", both deserved respect, because "each of them was certain he had right on his side and was morally obligated to go to the end in the name of truth." While Sakharov strongly disagreed with Teller over nuclear testing in the atmosphere and the Strategic Defense Initiative, he believed that American academics had been unfair to Teller's resolve to get the H-bomb for the United States since "all steps by the Americans of a temporary or permanent rejection of developing thermonuclear weapons would have been seen either as a clever feint, or as the manifestation of stupidity. In both cases, the reaction would have been the same – avoid the trap and immediately take advantage of the enemy's stupidity." + +Sakharov never felt that by creating nuclear weapons he had "known sin", in Oppenheimer's expression. He later wrote: + +Support for peaceful use of nuclear technology + +In 1950 he proposed an idea for a controlled nuclear fusion reactor, the tokamak, which is still the basis for the majority of work in the area. Sakharov, in association with Tamm, proposed confining extremely hot ionized plasma by torus shaped magnetic fields for controlling thermonuclear fusion that led to the development of the tokamak device. + +Magneto-implosive generators + +In 1951 he invented and tested the first explosively pumped flux compression generators, compressing magnetic fields by explosives. He called these devices MK (for MagnetoKumulative) generators. The radial MK-1 produced a pulsed magnetic field of 25 megagauss (2500 teslas). The resulting helical MK-2 generated 1000 million amperes in 1953. + +Sakharov then tested a MK-driven "plasma cannon" where a small aluminum ring was vaporized by huge eddy currents into a stable, self-confined toroidal plasmoid and was accelerated to 100 km/s. Sakharov later suggested replacing the copper coil in MK generators with a large superconductor solenoid to magnetically compress and focus underground nuclear explosions into a shaped charge effect. He theorized this could focus 1023 protons per second on a 1 mm2 surface. + +Particle physics and cosmology +After 1965 Sakharov returned to fundamental science and began working on particle physics and physical cosmology. + +He tried to explain the baryon asymmetry of the universe; in that regard, he was the first to give a theoretical motivation for proton decay. Proton decay was suggested by Wigner in 1949 and 1952. +Proton decay experiments had been performed since 1954 already. Sakharov was the first to consider CPT-symmetric events occurring before the Big Bang:We can visualize that neutral spinless maximons (or photons) are produced at ''t'' < 0 from contracting matter having an excess of antiquarks, that they pass "one through the other" at the instant ''t'' = 0 when the density is infinite, and decay with an excess of quarks when ''t'' > 0, realizing total CPT symmetry of the universe. All the phenomena at t < 0 are assumed in this hypothesis to be CPT reflections of the phenomena at t > 0. His legacy in this domain are the famous conditions named after him: Baryon number violation, C-symmetry and CP-symmetry violation, and interactions out of thermal equilibrium. + +Sakharov was also interested in explaining why the curvature of the universe is so small. This lead him to consider cyclic models, where the universe oscillates between contraction and expansion phases. In those models, after a certain number of cycles the curvature naturally becomes infinite even if it had not started this way: Sakharov considered three starting points, a flat universe with a slightly negative cosmological constant, a universe with a positive curvature and a zero cosmological constant, and a universe with a negative curvature and a slightly negative cosmological constant. Those last two models feature what Sakharov calls a reversal of the time arrow, which can be summarized as follows: He considers times t > 0 after the initial Big Bang singularity at t = 0 (which he calls "Friedman singularity" and denotes Φ) as well as times t < 0 before that singularity. He then assumes that entropy increases when time increases for t > 0 as well as when time decreases for t < 0, which constitutes his reversal of time. Then he considers the case when the universe at t < 0 is the image of the universe at t > 0 under CPT symmetry but also the case when it is not so: the universe has a non-zero CPT charge at t = 0 in this case. Sakharov considers a variant of this model where the reversal of the time arrow occurs at a point of maximum entropy instead of happening at the singularity. In those models there is no dynamic interaction between the universe at t < 0 and t > 0. + +In his first model the two universes did not interact, except via local matter accumulation whose density and pressure become high enough to connect the two sheets through a bridge without spacetime between them, but with a continuity of geodesics beyond the Schwarzschild radius with no singularity, allowing an exchange of matter between the two conjugated sheets, based on an idea after Igor Dmitriyevich Novikov. Novikov called such singularities a collapse and an anticollapse, which are an alternative to the couple black hole and white hole in the wormhole model. Sakharov also proposed the idea of induced gravity as an alternative theory of quantum gravity. + +Turn to activism + +Since the late 1950s Sakharov had become concerned about the moral and political implications of his work. Politically active during the 1960s, Sakharov was against nuclear proliferation. Pushing for the end of atmospheric tests, he played a role in the 1963 Partial Test Ban Treaty, signed in Moscow. + +Sakharov was also involved in an event with political consequences in 1964, when the Soviet Academy of Sciences nominated for full membership Nikolai Nuzhdin, a follower of Trofim Lysenko (initiator of the Stalin-supported anti-genetics campaign Lysenkoism). Contrary to normal practice, Sakharov, a member of the academy, publicly spoke out against full membership for Nuzhdin and held him responsible for "the defamation, firing, arrest, even death, of many genuine scientists." In the end, Nuzhdin was not elected, but the episode prompted Nikita Khrushchev to order the KGB to gather compromising material on Sakharov. + +The major turn in Sakharov's political evolution came in 1967, when anti-ballistic missile defense became a key issue in US–Soviet relations. In a secret detailed letter to the Soviet leadership of July 21, 1967, Sakharov explained the need to "take the Americans at their word" and accept their proposal for a "bilateral rejection by the USA and the Soviet Union of the development of antiballistic missile defense" because an arms race in the new technology would otherwise increase the likelihood of nuclear war. He also asked permission to publish his manuscript, which accompanied the letter, in a newspaper to explain the dangers posed by that kind of defense. The government ignored his letter and refused to let him initiate a public discussion of ABMs in the Soviet press. + +Since 1967, after the Six Day War and the beginning of the Arab-Israeli conflict, he actively supported Israel, as he reported more than once in the press, and also maintained friendly relations with refuseniks who later made aliyah. + +In May 1968, Sakharov completed an essay, "Reflections on Progress, Peaceful Coexistence, and Intellectual Freedom". He described the anti-ballistic missile defense as a major threat of world nuclear war. After the essay was circulated in samizdat and then published outside the Soviet Union, Sakharov was banned from conducting any military-related research and returned to FIAN to study fundamental theoretical physics. + +For 12 years, until his exile to Gorky (Nizhny Novgorod) in January 1980, Sakharov assumed the role of a widely recognized and open dissident in Moscow. He stood vigil outside closed courtrooms, wrote appeals on behalf of more than 200 individual prisoners, and continued to write essays about the need for democratization. + +In 1970, Sakharov was among the three founding members of the Committee on Human Rights in the USSR, along with Valery Chalidze and Andrei Tverdokhlebov. The Committee wrote appeals, collected signatures for petitions and succeeded in affiliating with several international human rights organizations. Its work was the subject of many KGB reports and brought Sakharov under increasing pressure from the government. + +Sakharov married a fellow human rights activist, Yelena Bonner, in 1972. + +By 1973, Sakharov was meeting regularly with Western correspondents and holding press conferences in his apartment. He appealed to the US Congress to approve the 1974 Jackson-Vanik Amendment to a trade bill, which coupled trade tariffs to the Kremlin's willingness to allow freer emigration. + +Attacked by Soviet establishment from 1972 +In 1972, Sakharov became the target of sustained pressure from his fellow scientists in the Soviet Academy of Sciences and the Soviet press. The writer Aleksandr Solzhenitsyn came to his defence. + +In 1973 and 1974, the Soviet media campaign continued, targeting both Sakharov and Solzhenitsyn for their pro-Western, anti-socialist positions. + +Sakharov later described that it took "years" for him to "understand how much substitution, deceit, and lack of correspondence with reality there was" in the Soviet ideals. "At first I thought, despite everything that I saw with my own eyes, that the Soviet State was a breakthrough into the future, a kind of prototype for all countries". Then he came, in his words, to "the theory of symmetry: all governments and regimes to a first approximation are bad, all peoples are oppressed, and all are threatened by common dangers.": + + + +Sakharov's ideas on social development led him to put forward the principle of human rights as a new basis of all politics. In his works, he declared that "the principle 'what is not prohibited is allowed' should be understood literally", and defied what he saw as unwritten ideological rules imposed by the Communist Party on the society in spite of a democratic Soviet Constitution (1936): + + +In a letter written from exile, he cheered up a fellow physicist and free market advocate with the words: "Fortunately, the future is unpredictable and also – because of quantum effects – uncertain." For Sakharov, the indeterminacy of the future supported his belief that he could and should take personal responsibility for it. + +Nobel Peace Prize (1975) +In 1973, Sakharov was nominated for the Nobel Peace Prize, and in 1974, he was awarded the Prix mondial Cino Del Duca. + +Sakharov was awarded the Nobel Peace Prize in 1975. The Norwegian Nobel Committee called him "a spokesman for the conscience of mankind". In the words of the Nobel Committee's citation: "In a convincing manner Sakharov has emphasised that Man's inviolable rights provide the only safe foundation for genuine and enduring international cooperation." + +Sakharov was not allowed to leave the Soviet Union to collect the prize. His wife, Yelena Bonner, read his speech at the ceremony in Oslo, Norway. On the day the prize was awarded, Sakharov was in Vilnius, where the human rights activist Sergei Kovalev was being tried. In his Nobel lecture, "Peace, Progress, Human Rights", Sakharov called for an end to the arms race, greater respect for the environment, international cooperation, and universal respect for human rights. He included a list of prisoners of conscience and political prisoners in the Soviet Union and stated that he shared the prize with them. + +By 1976, the head of the KGB, Yuri Andropov, was prepared to call Sakharov "Domestic Enemy Number One" before a group of KGB officers. + +Internal exile (1980–1986) + +Sakharov was arrested on 22 January 1980, following his public protests against the Soviet intervention in Afghanistan in 1979, and was sent to the city of Gorky, now Nizhny Novgorod, a city that was off limits to foreigners. + +Between 1980 and 1986, Sakharov was kept under Soviet police surveillance. In his memoirs, he mentioned that their apartment in Gorky was repeatedly subjected to searches and heists. Sakharov was named the 1980 Humanist of the Year by the American Humanist Association. + +In May 1984, Sakharov's wife, Yelena Bonner, was detained, and Sakharov began a hunger strike, demanding permission for his wife to travel to the United States for heart surgery. He was forcibly hospitalized and force-fed. He was held in isolation for four months. In August 1984, Bonner was sentenced by a court to five years of exile in Gorky. + +In April 1985, Sakharov started a new hunger strike for his wife to travel abroad for medical treatment. He again was taken to a hospital and force-fed. In August, the Politburo discussed what to do about Sakharov. He remained in the hospital until October 1985, when his wife was allowed to travel to the United States. She had heart surgery in the United States and returned to Gorky in June 1986. + +In December 1985, the European Parliament established the Sakharov Prize for Freedom of Thought, to be given annually for outstanding contributions to human rights. + +On 19 December 1986, Mikhail Gorbachev, who had initiated the policies of perestroika and glasnost, called Sakharov to tell him that he and his wife could return to Moscow. + +Political leader + +In 1988, Sakharov was given the International Humanist Award by the International Humanist and Ethical Union. He helped to initiate the first independent legal political organizations and became prominent in the Soviet Union's growing political opposition. In March 1989, Sakharov was elected to the new parliament, the All-Union Congress of People's Deputies and co-led the democratic opposition, the Inter-Regional Deputies Group. In November the head of the KGB reported to Gorbachev on Sakharov's encouragement and support for the coal miners' strike in Vorkuta. + +In December 1988, Sakharov visited Armenia and Azerbaijan on a fact-finding mission. He concluded, "For Azerbaijan the issue of Karabakh is a matter of ambition, for the Armenians of Karabakh, it is a matter of life and death". + +Death + +Soon after 9 p.m. on 14 December 1989, Sakharov went to his study to take a nap before preparing an important speech he was to deliver the next day in the Congress. His wife went to wake him at 11pm as he had requested but she found Sakharov dead on the floor. According to the notes of Yakov Rapoport, a senior pathologist present at the autopsy, it is most likely that Sakharov died of an arrhythmia consequent to dilated cardiomyopathy at the age of 68. He was interred in the Vostryakovskoye Cemetery in Moscow. + +Influence + +Memorial prizes +The Sakharov Prize for Freedom of Thought was established in 1988 by the European Parliament in his honour, and is the highest tribute to human rights endeavours awarded by the European Union. It is awarded annually by the parliament to "those who carry the spirit of Soviet dissident Andrei Sakharov"; to "Laureates who, like Sakharov, dedicate their lives to peaceful struggle for human rights." + +An Andrei Sakharov prize has also been awarded by the American Physical Society every second year since 2006 "to recognize outstanding leadership and/or achievements of scientists in upholding human rights". + +The Andrei Sakharov Prize for Writer's Civic Courage was established in October 1990. + +In 2004, with the approval of Yelena Bonner, an annual Sakharov Prize for journalism was established for reporters and commentators in Russia. Funded by former Soviet dissident Pyotr Vins, now a businessman in the US, the prize is administered by the Glasnost Defence Foundation in Moscow. The prize "for journalism as an act of conscience" has been won over the years by famous journalists such as Anna Politkovskaya and young reporters and editors working far from Russia's media capital, Moscow. The 2015 winner was Yelena Kostyuchenko. + +Andrei Sakharov Archives and Human Rights Center +The Andrei Sakharov Archives and Human Rights Center, established at Brandeis University in 1993, are now housed at Harvard University. +The documents from that archive were published by the Yale University Press in 2005. These documents are available online. +Most of documents of the archive are letters from the head of the KGB to the Central Committee about activities of Soviet dissidents and recommendations about the interpretation in newspapers. The letters cover the period from 1968 to 1991 (Brezhnev stagnation). The documents characterize not only Sakharov's activity, but that of other dissidents, as well as that of highest-position apparatchiks and the KGB. No Russian equivalent of the KGB archive is available. + +Legacy and remembrance + +Places + + In Moscow, there is Academician Sakharov Avenue and Sakharov Center. + During the 1980s, the block of 16th Street NW between L and M streets, in front of the Soviet embassy in Washington, D.C. (which later became the Russian ambassador's residence) was renamed "Andrei Sakharov Plaza" as a form of protest against his 1980 arrest and detention. + In Yerevan, the capital of Armenia, Sakharov Square, located in the heart of the city, is named after him. + The Sakharov Gardens (est. 1990) are located at the entrance to Jerusalem, Israel, off the Jerusalem–Tel Aviv Highway. There is also a street named after him in Haifa. + In Nizhny Novgorod, there is a Sakharov Museum in the apartment on the first floor of the 12-storeyed house where the Sakharov family lived for seven years; in 2014 his monument was erected near the house. + In Saint Petersburg, his monument stands in Sakharov Square, and there is a Sakharov Park. + In 1979, an asteroid, 1979 Sakharov, was named after him. + A public square in Vilnius in front of the Press House is named after Sakharov. The square was named on 16 March 1991, as the Press House was still occupied by the Soviet Army. + Andreja Saharova iela in the district of Pļavnieki in Riga, Latvia, is named after Sakharov. + Andreij-Sacharow-Platz in downtown Nuremberg is named in honour of Sakharov. + In Belarus, International Sakharov Environmental University was named after him. + Intersection of Ventura Blvd and Laurel Canyon Blvd in Studio City, Los Angeles, is named Andrei Sakharov Square. + In Arnhem, the bridge over the Nederrijn is called the Andrej Sacharovbrug. + The Andrej Sacharovweg is a street in Assen, Netherlands. There are also streets named in his honour in other places in the Netherlands such as Amsterdam, Amstelveen, The Hague, Hellevoetsluis, Leiden, Purmerend, Rotterdam, Utrecht + A street in Copenhagen, Denmark. + Quai Andreï Sakharov in Tournai, Belgium, is named in honour of Sakharov. + In Poland, streets named in his honour in Warsaw, Łódź and Kraków. + Andreï Sakharov Boulevard in the district of Mladost in Sofia, Bulgaria, is named after him. + In New York, a street sign at the southwest corner of Third Avenue and 67th Street reads Sakharov-Bonner Corner, in honor of Sakharov and his wife, Yelena Bonner. The corner is just down the block from the Soviet Mission to the United Nations (which later became the Russian mission) and was the scene of repeated anti-Soviet demonstrations. + In Chisinau, the capital of Moldova, there is Academician Andrei Sakharov street. + +Media + In the 1984 made-for-TV film Sakharov starring Jason Robards. + In the television series Star Trek: The Next Generation, one of the Enterprise-D's Shuttlecraft is named after Sakharov, and is featured prominently in several episodes. This follows the Star Trek tradition of naming Shuttlecraft after prominent scientists, and particularly in The Next Generation, physicists. + The fictitious interplanetary spacecraft Cosmonaut Alexei Leonov from the novel 2010: Odyssey Two by Arthur C. Clarke is powered by a "Sakharov drive". The novel was published in 1982, when Sakharov was in exile in Nizhny Novgorod, and was dedicated both to Sakharov and to Alexei Leonov. + Russian singer Alexander Gradsky wrote and performed the song "Памяти А. Д. Сахарова" ("In memory of Andrei Sakharov"), which features on his Live In "Russia" 2 (Живем в "России" 2) CD. + The faction leader of the Ecologists in the PC game S.T.A.L.K.E.R.: Shadow of Chernobyl and its prequel is a scientist named Professor Sakharov. + +Honours and awards + Hero of Socialist Labour (three times: 12 August 1953; 20 June 1956; 7 March 1962). + Four Orders of Lenin. + Lenin Prize (1956). + Stalin Prize (1953). + Elected member of the American Academy of Arts and Sciences (1969) + Elected member of the National Academy of Sciences (1973) + +In 1980, Sakharov was stripped of all Soviet awards for "anti-Soviet activities". Later, during glasnost, he declined the return of his awards and, consequently, Mikhail Gorbachev did not sign the necessary decree. + + Prix mondial Cino Del Duca (1974). + Nobel Peace Prize (1975). + Elected member of the American Philosophical Society (1978) + Laurea Honoris Causa of the Sapienza University of Rome (1980). + Grand Cross of Order of the Cross of Vytis (posthumously on January 8, 2003). + +Bibliography + +Books + +Articles and interviews + +See also + + Sakharov conditions + Sakharov Prize + List of peace activists + Natan Sharansky + Stanislaw Ulam + Omid Kokabee + Mordechai Vanunu + +References + +Further reading + +External links + + The Andrei Sakharov Archives at the Houghton Library. + + Andrei Sakharov: Soviet Physics, Nuclear Weapons, and Human Rights . Web exhibit at the American Institute of Physics. + Andrei Sakharov: Photo-chronology + Annotated bibliography of Andrei Sakharov from the Alsos Digital Library + +Videos + + + +1921 births +1989 deaths +People from Moscow +World War II refugees +Russian physicists +Soviet physicists +Soviet nuclear physicists +20th-century Russian writers +Amnesty International prisoners of conscience held by the Soviet Union +European democratic socialists +Full Members of the USSR Academy of Sciences +Grand Crosses of the Order of the Cross of Vytis +Heroes of Socialist Labour +Recipients of the Lenin Prize +Members of the Congress of People's Deputies of the Soviet Union +Moscow State University alumni +Nobel Peace Prize laureates +Nuclear weapons program of the Soviet Union +Nuclear weapons scientists and engineers +People of the Cold War +Perestroika +Recipients of the Order of Lenin +Hunger strikers +Soviet atheists +Soviet inventors +Soviet memoirists +Soviet anti–nuclear weapons activists +Soviet dissidents +Soviet male writers +20th-century male writers +Soviet Nobel laureates +Soviet non-fiction writers +Soviet prisoners and detainees +Soviet psychiatric abuse whistleblowers +Recipients of the Stalin Prize +Writers from Moscow +Russian political prisoners +Political party founders +20th-century memoirists +Male non-fiction writers +Members of the American Philosophical Society +Soviet reformers +Soviet human rights activists +Deaths from cardiomyopathy +Fellows of the American Physical Society +Russian scientists +Astrobiology is a scientific field within the life and environmental sciences that studies the origins, early evolution, distribution, and future of life in the universe by investigating its deterministic conditions and contingent events. As a discipline, astrobiology is founded on the premise that life may exist beyond Earth. + +Research in astrobiology comprises three main areas: the study of habitable environments in the Solar System and beyond, the search for planetary biosignatures of past or present extraterrestrial life, and the study of the origin and early evolution of life on Earth. + +The field of astrobiology has its origins in the 20th century with the advent of space exploration and the discovery of exoplanets. Early astrobiology research focused on the search for extraterrestrial life and the study of the potential for life to exist on other planets. In the 1960s and 1970s, NASA began its astrobiology pursuits within the Viking program, which was the first US mission to land on Mars and search for signs of life. This mission, along with other early space exploration missions, laid the foundation for the development of astrobiology as a discipline. + +Regarding habitable environments, astrobiology investigates potential locations beyond Earth that could support life, such as Mars, Europa, and exoplanets, through research into the extremophiles populating austere environments on Earth, like volcanic and deep sea environments. Research within this topic is conducted utilising the methodology of the geosciences, especially geobiology, for astrobiological applications. + +The search for biosignatures involves the identification of signs of past or present life in the form of organic compounds, isotopic ratios, or microbial fossils. Research within this topic is conducted utilising the methodology of planetary and environmental science, especially atmospheric science, for astrobiological applications, and is often conducted through remote sensing and in situ missions. + +Astrobiology also concerns the study of the origin and early evolution of life on Earth to try to understand the conditions that are necessary for life to form on other planets. This research seeks to understand how life emerged from non-living matter and how it evolved to become the diverse array of organisms we see today. Research within this topic is conducted utilising the methodology of paleosciences, especially paleobiology, for astrobiological applications. + +Astrobiology is a rapidly developing field with a strong interdisciplinary aspect that holds many challenges and opportunities for scientists. Astrobiology programs and research centres are present in many universities and research institutions around the world, and space agencies like NASA and ESA have dedicated departments and programs for astrobiology research. + +Overview + +The term astrobiology was first proposed by the Russian astronomer Gavriil Tikhov in 1953. It is etymologically derived from the Greek , "star"; , "life"; and , -logia, "study". A close synonym is exobiology from the Greek Έξω, "external"; , "life"; and , -logia, "study", coined by American molecular biologist Joshua Lederberg; exobiology is considered to have a narrow scope limited to search of life external to Earth. Another associated term is xenobiology, from the Greek ξένος, "foreign"; , "life"; and -λογία, "study", coined by American science fiction writer Robert Heinlein in his work The Star Beast; xenobiology is now used in a more specialised sense, referring to 'biology based on foreign chemistry', whether of extraterrestrial or terrestrial (typically synthetic) origin. + +While the potential for extraterrestrial life, especially intelligent life, has been explored throughout human history within philosophy and narrative, the question is a verifiable hypothesis and thus a valid line of scientific inquiry; planetary scientist David Grinspoon calls it a field of natural philosophy, grounding speculation on the unknown in known scientific theory. + +The modern field of astrobiology can be traced back to the 1950s and 1960s with the advent of space exploration, when scientists began to seriously consider the possibility of life on other planets. In 1957, the Soviet Union launched Sputnik 1, the first artificial satellite, which marked the beginning of the Space Age. This event led to an increase in the study of the potential for life on other planets, as scientists began to consider the possibilities opened up by the new technology of space exploration. In 1959, NASA funded its first exobiology project, and in 1960, NASA founded the Exobiology Program, now one of four main elements of NASA's current Astrobiology Program. In 1971, NASA funded Project Cyclops, part of the search for extraterrestrial intelligence, to search radio frequencies of the electromagnetic spectrum for interstellar communications transmitted by extraterrestrial life outside the Solar System. In the 1960s-1970s, NASA established the Viking program, which was the first US mission to land on Mars and search for metabolic signs of present life; the results were inconclusive. + +In the 1980s and 1990s, the field began to expand and diversify as new discoveries and technologies emerged. The discovery of microbial life in extreme environments on Earth, such as deep-sea hydrothermal vents, helped to clarify the feasibility of potential life existing in harsh conditions. The development of new techniques for the detection of biosignatures, such as the use of stable isotopes, also played a significant role in the evolution of the field. + +The contemporary landscape of astrobiology emerged in the early 21st century, focused on utilising Earth and environmental science for applications within comparate space environments. Missions included the ESA's Beagle 2, which failed minutes after landing on Mars, NASA's Phoenix lander, which probed the environment for past and present planetary habitability of microbial life on Mars and researched the history of water, and NASA's Curiosity rover, currently probing the environment for past and present planetary habitability of microbial life on Mars. + +Theoretical foundations + +Planetary habitability + +Astrobiological research makes a number of simplifying assumptions when studying the necessary components for planetary habitability. + +Carbon and Organic Compounds: Carbon is the fourth most abundant element in the universe and the energy required to make or break a bond is at just the appropriate level for building molecules which are not only stable, but also reactive. The fact that carbon atoms bond readily to other carbon atoms allows for the building of extremely long and complex molecules. As such, astrobiological research presumes that the vast majority of life forms in the Milky Way galaxy are based on carbon chemistries, as are all life forms on Earth. However, theoretical astrobiology entertains the potential for other organic molecular bases for life, thus astrobiological research often focuses on identifying environments that have the potential to support life based on the presence of organic compounds. + +Liquid water: Liquid water is a common molecule that provides an excellent environment for the formation of complicated carbon-based molecules, and is generally considered necessary for life as we know it to exist. Thus, astrobiological research presumes that extraterrestrial life similarly depends upon access to liquid water, and often focuses on identifying environments that have the potential to support liquid water. Some researchers posit environments of water-ammonia mixtures as possible solvents for hypothetical types of biochemistry. + +Environmental Stability: Where organisms adaptively evolve to the conditions of the environments in which they reside, environmental stability is considered necessary for life to exist. This presupposes the necessity of a stable temperature, pressure, and radiation levels; resultantly, astrobiological research focuses on planets orbiting Sun-like red dwarf stars. This is because very large stars have relatively short lifetimes, meaning that life might not have time to emerge on planets orbiting them; very small stars provide so little heat and warmth that only planets in very close orbits around them would not be frozen solid, and in such close orbits these planets would be tidally locked to the star; whereas the long lifetimes of red dwarfs could allow the development of habitable environments on planets with thick atmospheres. This is significant as red dwarfs are extremely common. (See also: Habitability of red dwarf systems). + +Energy source: It is assumed that any life elsewhere in the universe would also require an energy source. Previously, it was assumed that this would necessarily be from a sun-like star, however with developments within extremophile research contemporary astrobiological research often focuses on identifying environments that have the potential to support life based on the availability of an energy source, such as the presence of volcanic activity on a planet or moon that could provide a source of heat and energy. + +It is important to note that these assumptions are based on our current understanding of life on Earth and the conditions under which it can exist. As our understanding of life and the potential for it to exist in different environments evolves, these assumptions may change. + +Methodology + +Astrobiological research concerning the study of habitable environments in our solar system and beyond utilises methodologies within the geosciences. Research within this branch primarily concerns the geobiology of organisms that can survive in extreme environments on Earth, such as in volcanic or deep sea environments, to understand the limits of life, and the conditions under which life might be able to survive on other planets. This includes, but is not limited to; + +Deep-sea extremophiles: Researchers are studying organisms that live in the extreme environments of deep-sea hydrothermal vents and cold seeps. These organisms survive in the absence of sunlight, and some are able to survive in high temperatures and pressures, and use chemical energy instead of sunlight to produce food. + +Desert extremophiles: Researchers are studying organisms that can survive in extreme dry, high temperature conditions, such as in deserts. + +Microbes in extreme environments: Researchers are investigating the diversity and activity of microorganisms in environments such as deep mines, subsurface soil, cold glaciers and polar ice, and high-altitude environments. + +Research also regards the long-term survival of life on Earth, and the possibilities and hazards of life on other planets, including; + +Biodiversity and ecosystem resilience: Scientists are studying how the diversity of life and the interactions between different species contribute to the resilience of ecosystems and their ability to recover from disturbances. + +Climate change and extinction: Researchers are investigating the impacts of climate change on different species and ecosystems, and how they may lead to extinction or adaptation. This includes the evolution of Earth's climate and geology, and their potential impact on the habitability of the planet in the future, especially for humans. + +Human impact on the biosphere: Scientists are studying the ways in which human activities, such as deforestation, pollution, and the introduction of invasive species, are affecting the biosphere and the long-term survival of life on Earth. + +Long-term preservation of life: Researchers are exploring ways to preserve samples of life on Earth for long periods of time, such as cryopreservation and genomic preservation, in the event of a catastrophic event that could wipe out most of life on Earth. + +Emerging astrobiological research concerning the search for planetary biosignatures of past or present extraterrestrial life utilise methodologies within planetary sciences. These include; + +The study of microbial life in the subsurface of Mars: Scientists are using data from Mars rover missions to study the composition of the subsurface of Mars, searching for biosignatures of past or present microbial life. + +The study of subsurface oceans on icy moons: Recent discoveries of subsurface oceans on moons such as Europa and Enceladus have opened up new habitability zones thus targets for the search for extraterrestrial life. Currently, missions like the Europa Clipper are being planned to search for biosignatures within these environments. + +The study of the atmospheres of planets: Scientists are studying the potential for life to exist in the atmospheres of planets, with a focus on the study of the physical and chemical conditions necessary for such life to exist, namely the detection of organic molecules and biosignature gases; for example, the study of the possibility of life in the atmospheres of exoplanets that orbit red dwarfs and the study of the potential for microbial life in the upper atmosphere of Venus. + +Telescopes and remote sensing of exoplanets: The discovery of thousands of exoplanets has opened up new opportunities for the search for biosignatures. Scientists are using telescopes such as the James Webb Space Telescope and the Transiting Exoplanet Survey Satellite to search for biosignatures on exoplanets. They are also developing new techniques for the detection of biosignatures, such as the use of remote sensing to search for biosignatures in the atmosphere of exoplanets. + +SETI and CETI: Scientists search for signals from intelligent extraterrestrial civilizations using radio and optical telescopes within the discipline of extraterrestrial intelligence communications (CETI). CETI focuses on composing and deciphering messages that could theoretically be understood by another technological civilization. Communication attempts by humans have included broadcasting mathematical languages, pictorial systems such as the Arecibo message, and computational approaches to detecting and deciphering 'natural' language communication. While some high-profile scientists, such as Carl Sagan, have advocated the transmission of messages, theoretical physicist Stephen Hawking warned against it, suggesting that aliens may raid Earth for its resources. + +Emerging astrobiological research concerning the study of the origin and early evolution of life on Earth utilises methodologies within the palaeosciences. These include; + +The study of the early atmosphere: Researchers are investigating the role of the early atmosphere in providing the right conditions for the emergence of life, such as the presence of gases that could have helped to stabilise the climate and the formation of organic molecules. + +The study of the early magnetic field: Researchers are investigating the role of the early magnetic field in protecting the Earth from harmful radiation and helping to stabilise the climate. This research has immense astrobiological implications where the subjects of current astrobiological research like Mars lack such a field. + +The study of prebiotic chemistry: Scientists are studying the chemical reactions that could have occurred on the early Earth that led to the formation of the building blocks of life- amino acids, nucleotides, and lipids- and how these molecules could have formed spontaneously under early Earth conditions. + +The study of impact events: Scientists are investigating the potential role of impact events- especially meteorites- in the delivery of water and organic molecules to early Earth. + +The study of the primordial soup: Researchers are investigating the conditions and ingredients that were present on the early Earth that could have led to the formation of the first living organisms, such as the presence of water and organic molecules, and how these ingredients could have led to the formation of the first living organisms. This includes the role of water in the formation of the first cells and in catalysing chemical reactions. + +The study of the role of minerals: Scientists are investigating the role of minerals like clay in catalysing the formation of organic molecules, thus playing a role in the emergence of life on Earth. + +The study of the role of energy and electricity: Scientists are investigating the potential sources of energy and electricity that could have been available on the early Earth, and their role in the formation of organic molecules, thus the emergence of life. + +The study of the early oceans: Scientists are investigating the composition and chemistry of the early oceans and how it may have played a role in the emergence of life, such as the presence of dissolved minerals that could have helped to catalyse the formation of organic molecules. + +The study of hydrothermal vents: Scientists are investigating the potential role of hydrothermal vents in the origin of life, as these environments may have provided the energy and chemical building blocks needed for its emergence. + +The study of plate tectonics: Scientists are investigating the role of plate tectonics in creating a diverse range of environments on the early Earth. + +The study of the early biosphere: Researchers are investigating the diversity and activity of microorganisms in the early Earth, and how these organisms may have played a role in the emergence of life. + +The study of microbial fossils: Scientists are investigating the presence of microbial fossils in ancient rocks, which can provide clues about the early evolution of life on Earth and the emergence of the first organisms. + +Research + +The systematic search for possible life outside Earth is a valid multidisciplinary scientific endeavor. However, hypotheses and predictions as to its existence and origin vary widely, and at the present, the development of hypotheses firmly grounded on science may be considered astrobiology's most concrete practical application. It has been proposed that viruses are likely to be encountered on other life-bearing planets, and may be present even if there are no biological cells. + +Research outcomes + +, no evidence of extraterrestrial life has been identified. Examination of the Allan Hills 84001 meteorite, which was recovered in Antarctica in 1984 and originated from Mars, is thought by David McKay, as well as few other scientists, to contain microfossils of extraterrestrial origin; this interpretation is controversial. + +Yamato 000593, the second largest meteorite from Mars, was found on Earth in 2000. At a microscopic level, spheres are found in the meteorite that are rich in carbon compared to surrounding areas that lack such spheres. The carbon-rich spheres may have been formed by biotic activity according to some NASA scientists. + +On 5 March 2011, Richard B. Hoover, a scientist with the Marshall Space Flight Center, speculated on the finding of alleged microfossils similar to cyanobacteria in CI1 carbonaceous meteorites in the fringe Journal of Cosmology, a story widely reported on by mainstream media. However, NASA formally distanced itself from Hoover's claim. According to American astrophysicist Neil deGrasse Tyson: "At the moment, life on Earth is the only known life in the universe, but there are compelling arguments to suggest we are not alone." + +Elements of astrobiology + +Astronomy + +Most astronomy-related astrobiology research falls into the category of extrasolar planet (exoplanet) detection, the hypothesis being that if life arose on Earth, then it could also arise on other planets with similar characteristics. To that end, a number of instruments designed to detect Earth-sized exoplanets have been considered, most notably NASA's Terrestrial Planet Finder (TPF) and ESA's Darwin programs, both of which have been cancelled. NASA launched the Kepler mission in March 2009, and the French Space Agency launched the COROT space mission in 2006. There are also several less ambitious ground-based efforts underway. + +The goal of these missions is not only to detect Earth-sized planets but also to directly detect light from the planet so that it may be studied spectroscopically. By examining planetary spectra, it would be possible to determine the basic composition of an extrasolar planet's atmosphere and/or surface. Given this knowledge, it may be possible to assess the likelihood of life being found on that planet. A NASA research group, the Virtual Planet Laboratory, is using computer modeling to generate a wide variety of virtual planets to see what they would look like if viewed by TPF or Darwin. It is hoped that once these missions come online, their spectra can be cross-checked with these virtual planetary spectra for features that might indicate the presence of life. + +An estimate for the number of planets with intelligent communicative extraterrestrial life can be gleaned from the Drake equation, essentially an equation expressing the probability of intelligent life as the product of factors such as the fraction of planets that might be habitable and the fraction of planets on which life might arise: + +where: + N = The number of communicative civilizations + R* = The rate of formation of suitable stars (stars such as the Sun) + fp = The fraction of those stars with planets (current evidence indicates that planetary systems may be common for stars like the Sun) + ne = The number of Earth-sized worlds per planetary system + fl = The fraction of those Earth-sized planets where life actually develops + fi = The fraction of life sites where intelligence develops + fc = The fraction of communicative planets (those on which electromagnetic communications technology develops) + L = The "lifetime" of communicating civilizations + +However, whilst the rationale behind the equation is sound, it is unlikely that the equation will be constrained to reasonable limits of error any time soon. The problem with the formula is that it is not used to generate or support hypotheses because it contains factors that can never be verified. The first term, R*, number of stars, is generally constrained within a few orders of magnitude. The second and third terms, fp, stars with planets and fe, planets with habitable conditions, are being evaluated for the star's neighborhood. Drake originally formulated the equation merely as an agenda for discussion at the Green Bank conference, but some applications of the formula had been taken literally and related to simplistic or pseudoscientific arguments. Another associated topic is the Fermi paradox, which suggests that if intelligent life is common in the universe, then there should be obvious signs of it. + +Another active research area in astrobiology is planetary system formation. It has been suggested that the peculiarities of the Solar System (for example, the presence of Jupiter as a protective shield) may have greatly increased the probability of intelligent life arising on Earth. + +Biology + +Biology cannot state that a process or phenomenon, by being mathematically possible, has to exist forcibly in an extraterrestrial body. Biologists specify what is speculative and what is not. The discovery of extremophiles, organisms able to survive in extreme environments, became a core research element for astrobiologists, as they are important to understand four areas in the limits of life in planetary context: the potential for panspermia, forward contamination due to human exploration ventures, planetary colonization by humans, and the exploration of extinct and extant extraterrestrial life. + +Until the 1970s, life was thought to be entirely dependent on energy from the Sun. Plants on Earth's surface capture energy from sunlight to photosynthesize sugars from carbon dioxide and water, releasing oxygen in the process that is then consumed by oxygen-respiring organisms, passing their energy up the food chain. Even life in the ocean depths, where sunlight cannot reach, was thought to obtain its nourishment either from consuming organic detritus rained down from the surface waters or from eating animals that did. The world's ability to support life was thought to depend on its access to sunlight. However, in 1977, during an exploratory dive to the Galapagos Rift in the deep-sea exploration submersible Alvin, scientists discovered colonies of giant tube worms, clams, crustaceans, mussels, and other assorted creatures clustered around undersea volcanic features known as black smokers. These creatures thrive despite having no access to sunlight, and it was soon discovered that they comprise an entirely independent ecosystem. Although most of these multicellular lifeforms need dissolved oxygen (produced by oxygenic photosynthesis) for their aerobic cellular respiration and thus are not completely independent from sunlight by themselves, the basis for their food chain is a form of bacterium that derives its energy from oxidization of reactive chemicals, such as hydrogen or hydrogen sulfide, that bubble up from the Earth's interior. Other lifeforms entirely decoupled from the energy from sunlight are green sulfur bacteria which are capturing geothermal light for anoxygenic photosynthesis or bacteria running chemolithoautotrophy based on the radioactive decay of uranium. This chemosynthesis revolutionized the study of biology and astrobiology by revealing that life need not be sunlight-dependent; it only requires water and an energy gradient in order to exist. + +Biologists have found extremophiles that thrive in ice, boiling water, acid, alkali, the water core of nuclear reactors, salt crystals, toxic waste and in a range of other extreme habitats that were previously thought to be inhospitable for life. This opened up a new avenue in astrobiology by massively expanding the number of possible extraterrestrial habitats. Characterization of these organisms, their environments and their evolutionary pathways, is considered a crucial component to understanding how life might evolve elsewhere in the universe. For example, some organisms able to withstand exposure to the vacuum and radiation of outer space include the lichen fungi Rhizocarpon geographicum and Xanthoria elegans, the bacterium Bacillus safensis, Deinococcus radiodurans, Bacillus subtilis, yeast Saccharomyces cerevisiae, seeds from Arabidopsis thaliana ('mouse-ear cress'), as well as the invertebrate animal Tardigrade. While tardigrades are not considered true extremophiles, they are considered extremotolerant microorganisms that have contributed to the field of astrobiology. Their extreme radiation tolerance and presence of DNA protection proteins may provide answers as to whether life can survive away from the protection of the Earth's atmosphere. + +Jupiter's moon, Europa, and Saturn's moon, Enceladus, are now considered the most likely locations for extant extraterrestrial life in the Solar System due to their subsurface water oceans where radiogenic and tidal heating enables liquid water to exist. + +The origin of life, known as abiogenesis, distinct from the evolution of life, is another ongoing field of research. Oparin and Haldane postulated that the conditions on the early Earth were conducive to the formation of organic compounds from inorganic elements and thus to the formation of many of the chemicals common to all forms of life we see today. The study of this process, known as prebiotic chemistry, has made some progress, but it is still unclear whether or not life could have formed in such a manner on Earth. The alternative hypothesis of panspermia is that the first elements of life may have formed on another planet with even more favorable conditions (or even in interstellar space, asteroids, etc.) and then have been carried over to Earth. + +The cosmic dust permeating the universe contains complex organic compounds ("amorphous organic solids with a mixed aromatic-aliphatic structure") that could be created naturally, and rapidly, by stars. Further, a scientist suggested that these compounds may have been related to the development of life on Earth and said that, "If this is the case, life on Earth may have had an easier time getting started as these organics can serve as basic ingredients for life." + +More than 20% of the carbon in the universe may be associated with polycyclic aromatic hydrocarbons (PAHs), possible starting materials for the formation of life. PAHs seem to have been formed shortly after the Big Bang, are widespread throughout the universe, and are associated with new stars and exoplanets. PAHs are subjected to interstellar medium conditions and are transformed through hydrogenation, oxygenation and hydroxylation, to more complex organics—"a step along the path toward amino acids and nucleotides, the raw materials of proteins and DNA, respectively". + +In October 2020, astronomers proposed the idea of detecting life on distant planets by studying the shadows of trees at certain times of the day to find patterns that could be detected through observation of exoplanets. + +Rare Earth hypothesis + +The Rare Earth hypothesis postulates that multicellular life forms found on Earth may actually be more of a rarity than scientists assume. According to this hypothesis, life on Earth (and more, multi-cellular life) is possible because of a conjunction of the right circumstances (galaxy and location within it, planetary system, star, orbit, planetary size, atmosphere, etc.); and the chance for all those circumstances to repeat elsewhere may be rare. It provides a possible answer to the Fermi paradox which suggests, "If extraterrestrial aliens are common, why aren't they obvious?" It is apparently in opposition to the principle of mediocrity, assumed by famed astronomers Frank Drake, Carl Sagan, and others. The principle of mediocrity suggests that life on Earth is not exceptional, and it is more than likely to be found on innumerable other worlds. + +Missions +Research into the environmental limits of life and the workings of extreme ecosystems is ongoing, enabling researchers to better predict what planetary environments might be most likely to harbor life. Missions such as the Phoenix lander, Mars Science Laboratory, ExoMars, Mars 2020 rover to Mars, and the Cassini probe to Saturn's moons aim to further explore the possibilities of life on other planets in the Solar System. + +Viking program + +The two Viking landers each carried four types of biological experiments to the surface of Mars in the late 1970s. These were the only Mars landers to carry out experiments looking specifically for metabolism by current microbial life on Mars. The landers used a robotic arm to collect soil samples into sealed test containers on the craft. The two landers were identical, so the same tests were carried out at two places on Mars' surface; Viking 1 near the equator and Viking 2 further north. The result was inconclusive, and is still disputed by some scientists. + +Norman Horowitz was the chief of the Jet Propulsion Laboratory bioscience section for the Mariner and Viking missions from 1965 to 1976. Horowitz considered that the great versatility of the carbon atom makes it the element most likely to provide solutions, even exotic solutions, to the problems of survival of life on other planets. However, he also considered that the conditions found on Mars were incompatible with carbon based life. + +Beagle 2 + +Beagle 2 was an unsuccessful British Mars lander that formed part of the European Space Agency's 2003 Mars Express mission. Its primary purpose was to search for signs of life on Mars, past or present. Although it landed safely, it was unable to correctly deploy its solar panels and telecom antenna. + +EXPOSE +EXPOSE is a multi-user facility mounted in 2008 outside the International Space Station dedicated to astrobiology. EXPOSE was developed by the European Space Agency (ESA) for long-term spaceflights that allow exposure of organic chemicals and biological samples to outer space in low Earth orbit. + +Mars Science Laboratory +The Mars Science Laboratory (MSL) mission landed the Curiosity rover that is currently in operation on Mars. It was launched 26 November 2011, and landed at Gale Crater on 6 August 2012. Mission objectives are to help assess Mars' habitability and in doing so, determine whether Mars is or has ever been able to support life, collect data for a future human mission, study Martian geology, its climate, and further assess the role that water, an essential ingredient for life as we know it, played in forming minerals on Mars. + +Tanpopo +The Tanpopo mission is an orbital astrobiology experiment investigating the potential interplanetary transfer of life, organic compounds, and possible terrestrial particles in the low Earth orbit. The purpose is to assess the panspermia hypothesis and the possibility of natural interplanetary transport of microbial life as well as prebiotic organic compounds. Early mission results show evidence that some clumps of microorganism can survive for at least one year in space. This may support the idea that clumps greater than 0.5 millimeters of microorganisms could be one way for life to spread from planet to planet. + +ExoMars rover + +ExoMars is a robotic mission to Mars to search for possible biosignatures of Martian life, past or present. This astrobiological mission is currently under development by the European Space Agency (ESA) in partnership with the Russian Federal Space Agency (Roscosmos); it is planned for a 2022 launch. + +Mars 2020 + +Mars 2020 successfully landed its rover Perseverance in Jezero Crater on 18 February 2021. It will investigate environments on Mars relevant to astrobiology, investigate its surface geological processes and history, including the assessment of its past habitability and potential for preservation of biosignatures and biomolecules within accessible geological materials. The Science Definition Team is proposing the rover collect and package at least 31 samples of rock cores and soil for a later mission to bring back for more definitive analysis in laboratories on Earth. The rover could make measurements and technology demonstrations to help designers of a human expedition understand any hazards posed by Martian dust and demonstrate how to collect carbon dioxide (CO2), which could be a resource for making molecular oxygen (O2) and rocket fuel. + +Europa Clipper +Europa Clipper is a mission planned by NASA for a 2025 launch that will conduct detailed reconnaissance of Jupiter's moon Europa and will investigate whether its internal ocean could harbor conditions suitable for life. It will also aid in the selection of future landing sites. + +Dragonfly +Dragonfly is a NASA mission scheduled to land on Titan in 2036 to assess its microbial habitability and study its prebiotic chemistry. Dragonfly is a rotorcraft lander that will perform controlled flights between multiple locations on the surface, which allows sampling of diverse regions and geological contexts. + +Proposed concepts + +Icebreaker Life +Icebreaker Life is a lander mission that was proposed for NASA's Discovery Program for the 2021 launch opportunity, but it was not selected for development. It would have had a stationary lander that would be a near copy of the successful 2008 Phoenix and it would have carried an upgraded astrobiology scientific payload, including a 1-meter-long core drill to sample ice-cemented ground in the northern plains to conduct a search for organic molecules and evidence of current or past life on Mars. One of the key goals of the Icebreaker Life mission is to test the hypothesis that the ice-rich ground in the polar regions has significant concentrations of organics due to protection by the ice from oxidants and radiation. + +Journey to Enceladus and Titan +Journey to Enceladus and Titan (JET) is an astrobiology mission concept to assess the habitability potential of Saturn's moons Enceladus and Titan by means of an orbiter. + +Enceladus Life Finder +Enceladus Life Finder (ELF) is a proposed astrobiology mission concept for a space probe intended to assess the habitability of the internal aquatic ocean of Enceladus, Saturn's sixth-largest moon. + +Life Investigation For Enceladus +Life Investigation For Enceladus (LIFE) is a proposed astrobiology sample-return mission concept. The spacecraft would enter into Saturn orbit and enable multiple flybys through Enceladus' icy plumes to collect icy plume particles and volatiles and return them to Earth on a capsule. The spacecraft may sample Enceladus' plumes, the E ring of Saturn, and the upper atmosphere of Titan. + +Oceanus +Oceanus is an orbiter proposed in 2017 for the New Frontiers mission No. 4. It would travel to the moon of Saturn, Titan, to assess its habitability. Oceanus objectives are to reveal Titan's organic chemistry, geology, gravity, topography, collect 3D reconnaissance data, catalog the organics and determine where they may interact with liquid water. + +Explorer of Enceladus and Titan +Explorer of Enceladus and Titan (E2T) is an orbiter mission concept that would investigate the evolution and habitability of the Saturnian satellites Enceladus and Titan. The mission concept was proposed in 2017 by the European Space Agency. + +See also + + + + + + + + + + + + + + + + + + + + + + The Living Cosmos + +References + +Bibliography + The International Journal of Astrobiology, published by Cambridge University Press, is the forum for practitioners in this interdisciplinary field. + Astrobiology, published by Mary Ann Liebert, Inc., is a peer-reviewed journal that explores the origins of life, evolution, distribution, and destiny in the universe. + + + + +Loeb, Avi (2021). Extraterrestrial: The First Sign of Intelligent Life Beyond Earth. Houghton Mifflin Harcourt. + +Further reading + + D. Goldsmith, T. Owen, The Search For Life in the Universe, Addison-Wesley Publishing Company, 2001 (3rd edition). + Andy Weir's 2021 novel, Project Hail Mary, centers on astrobiology. + +External links + + Astrobiology.nasa.gov + UK Centre for Astrobiology + Spanish Centro de Astrobiología + Astrobiology Research at The Library of Congress + Astrobiology Survey – An introductory course on astrobiology + Summary - Search For Life Beyond Earth (NASA; 25 June 2021) + + +Extraterrestrial life +Origin of life +Astronomical sub-disciplines +Branches of biology +Speculative evolution +An air show (or airshow, air fair, air tattoo) is a public event where aircraft are exhibited. They often include aerobatics demonstrations, without they are called "static air shows" with aircraft parked on the ground. + +The largest air show measured by number of exhibitors and size of exhibit space is Le Bourget, followed by Farnborough, with the Dubai Airshow and Singapore Airshow both claiming third place. The largest air show or fly-in by number of participating aircraft is EAA AirVenture Oshkosh, with approximately 10,000 aircraft participating annually. The biggest military airshow in the world is the Royal International Air Tattoo, at RAF Fairford in England. On the other hand, FIDAE in II Air Brigade of the FACH, next to the Arturo Merino Benítez International Airport in Santiago, Chile, is the largest aerospace fair in Latin America and the Southern Hemisphere. + +Outline + +Some airshows are held as a business venture or as a trade event where aircraft, avionics and other services are promoted to potential customers. Many air shows are held in support of local, national or military charities. Military air firms often organise air shows at military airfields as a public relations exercise to thank the local community, promote military careers and raise the profile of the military. + +Air "seasons" vary around the world. The United States enjoys a long season that generally runs from March to November, covering the spring, summer, and fall seasons. Other countries often have much shorter seasons. In Japan air shows are generally events held at Japan Air Self-Defense Force bases regularly throughout the year. The European season usually starts in late April or Early May and is usually over by mid October. The Middle East, Australia, and New Zealand hold their events between January and March. However, for many acts, the "off-season" does not mean a period of inactivity; pilots and performers use this time for maintenance and practice. + +The type of displays seen at shows are constrained by a number of factors, including the weather and visibility. Most aviation authorities now publish rules and guidance on minimum display heights and criteria for differing conditions. In addition to the weather, pilots and organizers must also consider local airspace restrictions. Most exhibitors will plan "full", "rolling" and "flat" display for varying weather and airspace conditions. + +The types of shows vary greatly. Some are large scale military events with large flying displays and ground exhibitions while others held at small local airstrips can often feature just one or two hours of flying with just a few stalls on the ground. Air displays can be held during day or night with the latter becoming increasingly popular. Air shows often, but do not always, take place over airfields; some have been held over the grounds of stately homes or castles and over the sea at coastal resorts. + +The first public international airshow, at which many types of aircraft were displayed and flown, was the Grande Semaine d'Aviation de la Champagne, held Aug. 22–29, 1909 in Reims. This had been preceded by what may have been the first ever gathering of enthusiasts, June 28 – July 19 of the same year at the airfield at La Brayelle, near Douai. + +Attractions + +Before World War II, air shows were associated with long-distance air races, often lasting many days and covering thousands of miles. While the Reno Air Races keep this tradition alive, most air shows today primarily feature a series of aerial demos of short duration. + +Most air shows feature warbirds, aerobatics, and demonstrations of modern military aircraft, and many air shows offer a variety of other aeronautical attractions as well, such as wing-walking, radio-controlled aircraft, water/slurry drops from firefighting aircraft, simulated helicopter rescues and sky diving. + +Specialist aerobatic aircraft have powerful piston engines, light weight and big control surfaces, making them capable of very high roll rates and accelerations. A skilled pilot will be able to climb vertically, perform very tight turns, tumble his aircraft end-over-end and perform manoeuvres during loops. + +Larger airshows can be headlined by military jet demonstration teams, such as the United States Navy Blue Angels, United States Air Force Thunderbirds, Royal Canadian Air Force Snowbirds, Royal Air Force Red Arrows, and Swiss Air Force Patrouille Suisse, among many others. + +Solo military demos, also known as tactical demos, feature one aircraft. The demonstration focuses on the capabilities of modern military aircraft. The display will usually demonstrate the aircraft's very short (and often very loud) rolls, fast speeds, slow approach speeds, as well as their ability to quickly make tight turns, to climb quickly, and their ability to be precisely controlled at a large range of speeds. Manoeuvres include aileron rolls, barrel rolls, hesitation rolls, Cuban-8s, tight turns, high-alpha flight, a high-speed pass, double Immelmans, and touch-and-gos. Tactical demos may include simulated bomb drops, sometimes with pyrotechnics on the ground for effect. Aircraft with special characteristics that give them unique capabilities will often display those in their demos; For example, Russian fighters with thrust vectoring may be used to perform the cobra maneuver or the Kulbit, while VTOL aircraft such as the Harrier may display such vertical capabilities or perform complex maneuvers with them. Some military air shows also feature demonstrations of aircraft ordnance in airstrikes and close air support, using either blanks or live munitions. + +Safety + +Air shows may present some risk to spectators and aviators. Accidents have occurred, sometimes with a large loss of life, such as the 1988 Ramstein air show disaster (70 deaths) in Germany and the 2002 Sknyliv air show disaster (77 deaths) in Ukraine. + +Because of these accidents, the various aviation authorities around the world have set rules and guidance for those running and participating in air displays. For example, after the breakup of an aircraft at 1952 Farnborough air show (31 deaths), the separation between display and spectators was increased. Air displays are often monitored by aviation authorities to ensure safe procedures. + +In the United Kingdom, local authorities will first need to approve any application for an event to which the public is admitted. No approval, no event. The first priority must be to arrange insurance cover and details can be obtained from your local authority. An added complication is a whole new raft of legislation concerning Health & Safety in particular Corporate Manslaughter, which can involve the event organiser being charged with a criminal offence if any of the insurances and risk assessments are not fully completed well in advance of the event. If this very basic step is not completed then any further activity should be halted until it is. + +Rules govern the distance from the crowds that aircraft must fly. These vary according to the rating of the pilot/crew, the type of aircraft and the way the aircraft is being flown. For instance, slower, lighter aircraft are usually allowed closer and lower to the crowd than larger, faster types. Also, a fighter jet flying straight and level will be able to do so closer to the crowd and lower than if it were performing a roll or a loop. + +Pilots can get authorizations for differing types of displays (i.e. limbo flying, basic aerobatics to unlimited aerobatics) and to differing minimum base heights above the ground. To gain such authorizations, the pilots will have to demonstrate to an examiner that they can perform to those limits without endangering themselves, ground crew or spectators. + +Despite display rules and guidances, accidents have continued to happen. However, air show accidents are rare and where there is proper supervision air shows have impressive safety records. Each year, organizations such as International Council of Air Shows and European Airshow Council meet and discuss various subjects including air show safety where accidents are discussed and lessons learned. + +See also + Fly-in + Flypast + Barnstorming + List of airshow accidents + List of air shows + Teardrop turn + Whifferdill turn + Bessie Coleman + +References + +Further reading + Brett Holman, "The militarisation of aerial theatre: air displays and airmindedness in Britain and Australia between the world wars", Contemporary British History, vol. 33, no. 4 (2019), pp. 483–506. + Air Show Accidents: "Reviewing the Notams Before the Show to Avoid Accidents" + +External links + +International Council of Air Shows +Experimental Aircraft Association Calendar +Royal Aero Club Events +Flightglobal's Upcoming air shows + USAF Thunderbirds + Canadian Forces Snowbirds + + +History of transport events +The anthropic principle, also known as the "observation selection effect", is the hypothesis, first proposed in 1957 by Robert Dicke, that the range of possible observations that could be made about the universe is limited by the fact that observations could happen only in a universe capable of developing intelligent life. Proponents of the anthropic principle argue that it explains why the universe has the age and the fundamental physical constants necessary to accommodate conscious life, since if either had been different, no one would have been around to make observations. Anthropic reasoning is often used to deal with the idea that the universe seems to be finely tuned for the existence of life. + +There are many different formulations of the anthropic principle. Philosopher Nick Bostrom counts them at thirty, but the underlying principles can be divided into "weak" and "strong" forms, depending on the types of cosmological claims they entail. The weak anthropic principle (WAP), as defined by Brandon Carter, states that the universe's ostensible fine tuning is the result of selection bias (specifically survivorship bias). Most such arguments draw upon some notion of the multiverse for there to be a statistical population of universes from which to select. However, a single vast universe is sufficient for most forms of the WAP that do not specifically deal with fine tuning. Carter distinguished the WAP from the strong anthropic principle (SAP), which considers the universe in some sense compelled to eventually have conscious and sapient life emerge within it. A form of the latter known as the participatory anthropic principle, articulated by John Archibald Wheeler, suggests on the basis of quantum mechanics that the universe, as a condition of its existence, must be observed, thus implying one or more observers. Stronger yet is the final anthropic principle (FAP), proposed by John D. Barrow and Frank Tipler, which views the universe's structure as expressible by bits of information in such a way that information processing is inevitable and eternal. + +Definition and basis + +The principle was formulated as a response to a series of observations that the laws of nature and parameters of the universe have values that are consistent with conditions for life as it is known rather than values that would not be consistent with life on Earth. The anthropic principle states that this is an a posteriori necessity, because if life were impossible, no living entity would be there to observe it, and thus it would not be known. That is, it must be possible to observe some universe, and hence, the laws and constants of any such universe must accommodate that possibility. + +The term anthropic in "anthropic principle" has been argued to be a misnomer. While singling out the currently-observable kind of carbon-based life, none of the finely tuned phenomena require human life or some kind of carbon chauvinism. Any form of life or any form of heavy atom, stone, star, or galaxy would do; nothing specifically human or anthropic is involved. + +The anthropic principle has given rise to some confusion and controversy, partly because the phrase has been applied to several distinct ideas. All versions of the principle have been accused of discouraging the search for a deeper physical understanding of the universe. The anthropic principle is often criticized for lacking falsifiability and therefore its critics may point out that the anthropic principle is a non-scientific concept, even though the weak anthropic principle, "conditions that are observed in the universe must allow the observer to exist", is "easy" to support in mathematics and philosophy (i.e., it is a tautology or truism). However, building a substantive argument based on a tautological foundation is problematic. Stronger variants of the anthropic principle are not tautologies and thus make claims considered controversial by some and that are contingent upon empirical verification. + +Anthropic 'coincidences' + +In 1961, Robert Dicke noted that the age of the universe, as seen by living observers, cannot be random. Instead, biological factors constrain the universe to be more or less in a "golden age", neither too young nor too old. If the universe were one tenth as old as its present age, there would not have been sufficient time to build up appreciable levels of metallicity (levels of elements besides hydrogen and helium) especially carbon, by nucleosynthesis. Small rocky planets did not yet exist. If the universe were 10 times older than it actually is, most stars would be too old to remain on the main sequence and would have turned into white dwarfs, aside from the dimmest red dwarfs, and stable planetary systems would have already come to an end. Thus, Dicke explained the coincidence between large dimensionless numbers constructed from the constants of physics and the age of the universe, a coincidence that inspired Dirac's varying-G theory. + +Dicke later reasoned that the density of matter in the universe must be almost exactly the critical density needed to prevent the Big Crunch (the "Dicke coincidences" argument). The most recent measurements may suggest that the observed density of baryonic matter, and some theoretical predictions of the amount of dark matter, account for about 30% of this critical density, with the rest contributed by a cosmological constant. Steven Weinberg gave an anthropic explanation for this fact: he noted that the cosmological constant has a remarkably low value, some 120 orders of magnitude smaller than the value particle physics predicts (this has been described as the "worst prediction in physics"). However, if the cosmological constant were only several orders of magnitude larger than its observed value, the universe would suffer catastrophic inflation, which would preclude the formation of stars, and hence life. + +The observed values of the dimensionless physical constants (such as the fine-structure constant) governing the four fundamental interactions are balanced as if fine-tuned to permit the formation of commonly found matter and subsequently the emergence of life. A slight increase in the strong interaction (up to 50% for some authors) would bind the dineutron and the diproton and convert all hydrogen in the early universe to helium; likewise, an increase in the weak interaction also would convert all hydrogen to helium. Water, as well as sufficiently long-lived stable stars, both essential for the emergence of life as it is known, would not exist. More generally, small changes in the relative strengths of the four fundamental interactions can greatly affect the universe's age, structure, and capacity for life. + +Origin + +The phrase "anthropic principle" first appeared in Brandon Carter's contribution to a 1973 Kraków symposium honouring Copernicus's 500th birthday. Carter, a theoretical astrophysicist, articulated the Anthropic Principle in reaction to the Copernican Principle, which states that humans do not occupy a privileged position in the Universe. Carter said: "Although our situation is not necessarily central, it is inevitably privileged to some extent." Specifically, Carter disagreed with using the Copernican principle to justify the Perfect Cosmological Principle, which states that all large regions and times in the universe must be statistically identical. The latter principle underlies the steady-state theory, which had recently been falsified by the 1965 discovery of the cosmic microwave background radiation. This discovery was unequivocal evidence that the universe has changed radically over time (for example, via the Big Bang). + +Carter defined two forms of the anthropic principle, a "weak" one which referred only to anthropic selection of privileged spacetime locations in the universe, and a more controversial "strong" form that addressed the values of the fundamental constants of physics. + +Roger Penrose explained the weak form as follows: + +One reason this is plausible is that there are many other places and times in which humans could have evolved. But when applying the strong principle, there is only one universe, with one set of fundamental parameters, so what exactly is the point being made? Carter offers two possibilities: First, humans can use their own existence to make "predictions" about the parameters. But second, "as a last resort", humans can convert these predictions into explanations by assuming that there is more than one universe, in fact a large and possibly infinite collection of universes, something that is now called the multiverse ("world ensemble" was Carter's term), in which the parameters (and perhaps the laws of physics) vary across universes. The strong principle then becomes an example of a selection effect, exactly analogous to the weak principle. Postulating a multiverse is certainly a radical step, but taking it could provide at least a partial answer to a question seemingly out of the reach of normal science: "Why do the fundamental laws of physics take the particular form we observe and not another?" + +Since Carter's 1973 paper, the term anthropic principle has been extended to cover a number of ideas that differ in important ways from his. Particular confusion was caused by the 1986 book The Anthropic Cosmological Principle by John D. Barrow and Frank Tipler, which distinguished between a "weak" and "strong" anthropic principle in a way very different from Carter's, as discussed in the next section. + +Carter was not the first to invoke some form of the anthropic principle. In fact, the evolutionary biologist Alfred Russel Wallace anticipated the anthropic principle as long ago as 1904: "Such a vast and complex universe as that which we know exists around us, may have been absolutely required [...] in order to produce a world that should be precisely adapted in every detail for the orderly development of life culminating in man." In 1957, Robert Dicke wrote: "The age of the Universe 'now' is not random but conditioned by biological factors [...] [changes in the values of the fundamental constants of physics] would preclude the existence of man to consider the problem." + +Ludwig Boltzmann may have been one of the first in modern science to use anthropic reasoning. Prior to knowledge of the Big Bang Boltzmann's thermodynamic concepts painted a picture of a universe that had inexplicably low entropy. Boltzmann suggested several explanations, one of which relied on fluctuations that could produce pockets of low entropy or Boltzmann universes. While most of the universe is featureless in this model, to Boltzmann, it is unremarkable that humanity happens to inhabit a Boltzmann universe, as that is the only place where intelligent life could be. + +Variants + +Weak anthropic principle (WAP) (Carter): "... our location in the universe is necessarily privileged to the extent of being compatible with our existence as observers." Note that for Carter, "location" refers to our location in time as well as space. + +Strong anthropic principle (SAP) (Carter): "[T]he universe (and hence the fundamental parameters on which it depends) must be such as to admit the creation of observers within it at some stage. To paraphrase Descartes, cogito ergo mundus talis est."The Latin tag ("I think, therefore the world is such [as it is]") makes it clear that "must" indicates a deduction from the fact of our existence; the statement is thus a truism. + +In their 1986 book, The anthropic cosmological principle, John Barrow and Frank Tipler depart from Carter and define the WAP and SAP as follows: + +Weak anthropic principle (WAP) (Barrow and Tipler): "The observed values of all physical and cosmological quantities are not equally probable but they take on values restricted by the requirement that there exist sites where carbon-based life can evolve and by the requirements that the universe be old enough for it to have already done so."Unlike Carter they restrict the principle to carbon-based life, rather than just "observers". A more important difference is that they apply the WAP to the fundamental physical constants, such as the fine-structure constant, the number of spacetime dimensions, and the cosmological constant—topics that fall under Carter's SAP. + +Strong anthropic principle (SAP) (Barrow and Tipler): "The Universe must have those properties which allow life to develop within it at some stage in its history."This looks very similar to Carter's SAP, but unlike the case with Carter's SAP, the "must" is an imperative, as shown by the following three possible elaborations of the SAP, each proposed by Barrow and Tipler: + "There exists one possible Universe 'designed' with the goal of generating and sustaining 'observers'." +This can be seen as simply the classic design argument restated in the garb of contemporary cosmology. It implies that the purpose of the universe is to give rise to intelligent life, with the laws of nature and their fundamental physical constants set to ensure that life emerges and evolves. + "Observers are necessary to bring the Universe into being." +Barrow and Tipler believe that this is a valid conclusion from quantum mechanics, as John Archibald Wheeler has suggested, especially via his idea that information is the fundamental reality (see It from bit) and his Participatory anthropic principle (PAP) which is an interpretation of quantum mechanics associated with the ideas of John von Neumann and Eugene Wigner. + "An ensemble of other different universes is necessary for the existence of our Universe." +By contrast, Carter merely says that an ensemble of universes is necessary for the SAP to count as an explanation. + +The philosophers John Leslie and Nick Bostrom reject the Barrow and Tipler SAP as a fundamental misreading of Carter. For Bostrom, Carter's anthropic principle just warns us to make allowance for anthropic bias—that is, the bias created by anthropic selection effects (which Bostrom calls "observation" selection effects)—the necessity for observers to exist in order to get a result. He writes: + +Strong self-sampling assumption (SSSA) (Bostrom): "Each observer-moment should reason as if it were randomly selected from the class of all observer-moments in its reference class." Analysing an observer's experience into a sequence of "observer-moments" helps avoid certain paradoxes; but the main ambiguity is the selection of the appropriate "reference class": for Carter's WAP this might correspond to all real or potential observer-moments in our universe; for the SAP, to all in the multiverse. Bostrom's mathematical development shows that choosing either too broad or too narrow a reference class leads to counter-intuitive results, but he is not able to prescribe an ideal choice. + +According to Jürgen Schmidhuber, the anthropic principle essentially just says that the conditional probability of finding yourself in a universe compatible with your existence is always 1. It does not allow for any additional nontrivial predictions such as "gravity won't change tomorrow". To gain more predictive power, additional assumptions on the prior distribution of alternative universes are necessary. + +Playwright and novelist Michael Frayn describes a form of the strong anthropic principle in his 2006 book The Human Touch, which explores what he characterises as "the central oddity of the Universe": + +Character of anthropic reasoning +Carter chose to focus on a tautological aspect of his ideas, which has resulted in much confusion. In fact, anthropic reasoning interests scientists because of something that is only implicit in the above formal definitions, namely that humans should give serious consideration to there being other universes with different values of the "fundamental parameters"—that is, the dimensionless physical constants and initial conditions for the Big Bang. Carter and others have argued that life would not be possible in most such universes. In other words, the universe humans live in is fine tuned to permit life. Collins & Hawking (1973) characterized Carter's then-unpublished big idea as the postulate that "there is not one universe but a whole infinite ensemble of universes with all possible initial conditions". If this is granted, the anthropic principle provides a plausible explanation for the fine tuning of our universe: the "typical" universe is not fine-tuned, but given enough universes, a small fraction will be capable of supporting intelligent life. Ours must be one of these, and so the observed fine tuning should be no cause for wonder. + +Although philosophers have discussed related concepts for centuries, in the early 1970s the only genuine physical theory yielding a multiverse of sorts was the many-worlds interpretation of quantum mechanics. This would allow variation in initial conditions, but not in the truly fundamental constants. Since that time a number of mechanisms for producing a multiverse have been suggested: see the review by Max Tegmark. An important development in the 1980s was the combination of inflation theory with the hypothesis that some parameters are determined by symmetry breaking in the early universe, which allows parameters previously thought of as "fundamental constants" to vary over very large distances, thus eroding the distinction between Carter's weak and strong principles. At the beginning of the 21st century, the string landscape emerged as a mechanism for varying essentially all the constants, including the number of spatial dimensions. + +The anthropic idea that fundamental parameters are selected from a multitude of different possibilities (each actual in some universe or other) contrasts with the traditional hope of physicists for a theory of everything having no free parameters. As Albert Einstein said: "What really interests me is whether God had any choice in the creation of the world." In 2002, some proponents of the leading candidate for a "theory of everything", string theory, proclaimed "the end of the anthropic principle" since there would be no free parameters to select. In 2003, however, Leonard Susskind stated: "...it seems plausible that the landscape is unimaginably large and diverse. This is the behavior that gives credence to the anthropic principle." + +The modern form of a design argument is put forth by intelligent design. Proponents of intelligent design often cite the fine-tuning observations that (in part) preceded the formulation of the anthropic principle by Carter as a proof of an intelligent designer. Opponents of intelligent design are not limited to those who hypothesize that other universes exist; they may also argue, anti-anthropically, that the universe is less fine-tuned than often claimed, or that accepting fine tuning as a brute fact is less astonishing than the idea of an intelligent creator. Furthermore, even accepting fine tuning, Sober (2005) and Ikeda and Jefferys, argue that the anthropic principle as conventionally stated actually undermines intelligent design. + +Paul Davies's book The Goldilocks Enigma (2006) reviews the current state of the fine-tuning debate in detail, and concludes by enumerating the following responses to that debate: + + The absurd universe: Our universe just happens to be the way it is. + The unique universe: There is a deep underlying unity in physics that necessitates the Universe being the way it is. A Theory of Everything will explain why the various features of the Universe must have exactly the values that have been recorded. + The multiverse: Multiple universes exist, having all possible combinations of characteristics, and humans inevitably find themselves within a universe that allows us to exist. + Intelligent design: A creator designed the Universe with the purpose of supporting complexity and the emergence of intelligence. + The life principle: There is an underlying principle that constrains the Universe to evolve towards life and mind. + The self-explaining universe: A closed explanatory or causal loop: "perhaps only universes with a capacity for consciousness can exist". This is Wheeler's participatory anthropic principle (PAP). + The fake universe: Humans live inside a virtual reality simulation. + +Omitted here is Lee Smolin's model of cosmological natural selection, also known as fecund universes, which proposes that universes have "offspring" that are more plentiful if they resemble our universe. Also see Gardner (2005). + +Clearly each of these hypotheses resolve some aspects of the puzzle, while leaving others unanswered. Followers of Carter would admit only option 3 as an anthropic explanation, whereas 3 through 6 are covered by different versions of Barrow and Tipler's SAP (which would also include 7 if it is considered a variant of 4, as in Tipler 1994). + +The anthropic principle, at least as Carter conceived it, can be applied on scales much smaller than the whole universe. For example, Carter (1983) inverted the usual line of reasoning and pointed out that when interpreting the evolutionary record, one must take into account cosmological and astrophysical considerations. With this in mind, Carter concluded that given the best estimates of the age of the universe, the evolutionary chain culminating in Homo sapiens probably admits only one or two low probability links. + +Observational evidence +No possible observational evidence bears on Carter's WAP, as it is merely advice to the scientist and asserts nothing debatable. The obvious test of Barrow's SAP, which says that the universe is "required" to support life, is to find evidence of life in universes other than ours. Any other universe is, by most definitions, unobservable (otherwise it would be included in our portion of this universe). Thus, in principle Barrow's SAP cannot be falsified by observing a universe in which an observer cannot exist. + +Philosopher John Leslie states that the Carter SAP (with multiverse) predicts the following: + Physical theory will evolve so as to strengthen the hypothesis that early phase transitions occur probabilistically rather than deterministically, in which case there will be no deep physical reason for the values of fundamental constants; + Various theories for generating multiple universes will prove robust; + Evidence that the universe is fine tuned will continue to accumulate; + No life with a non-carbon chemistry will be discovered; + Mathematical studies of galaxy formation will confirm that it is sensitive to the rate of expansion of the universe. + +Hogan has emphasised that it would be very strange if all fundamental constants were strictly determined, since this would leave us with no ready explanation for apparent fine tuning. In fact, humans might have to resort to something akin to Barrow and Tipler's SAP: there would be no option for such a universe not to support life. + +Probabilistic predictions of parameter values can be made given: +a particular multiverse with a "measure", i.e. a well defined "density of universes" (so, for parameter X, one can calculate the prior probability P(X0) dX that X is in the range X0 < X < X0 + dX), and +an estimate of the number of observers in each universe, N(X) (e.g., this might be taken as proportional to the number of stars in the universe). +The probability of observing value X is then proportional to N(X) P(X). A generic feature of an analysis of this nature is that the expected values of the fundamental physical constants should not be "over-tuned", i.e. if there is some perfectly tuned predicted value (e.g. zero), the observed value need be no closer to that predicted value than what is required to make life possible. The small but finite value of the cosmological constant can be regarded as a successful prediction in this sense. + +One thing that would not count as evidence for the anthropic principle is evidence that the Earth or the Solar System occupied a privileged position in the universe, in violation of the Copernican principle (for possible counterevidence to this principle, see Copernican principle), unless there was some reason to think that that position was a necessary condition for our existence as observers. + +Applications of the principle + +The nucleosynthesis of carbon-12 +Fred Hoyle may have invoked anthropic reasoning to predict an astrophysical phenomenon. He is said to have reasoned, from the prevalence on Earth of life forms whose chemistry was based on carbon-12 nuclei, that there must be an undiscovered resonance in the carbon-12 nucleus facilitating its synthesis in stellar interiors via the triple-alpha process. He then calculated the energy of this undiscovered resonance to be 7.6 million electronvolts. Willie Fowler's research group soon found this resonance, and its measured energy was close to Hoyle's prediction. + +However, in 2010 Helge Kragh argued that Hoyle did not use anthropic reasoning in making his prediction, since he made his prediction in 1953 and anthropic reasoning did not come into prominence until 1980. He called this an "anthropic myth," saying that Hoyle and others made an after-the-fact connection between carbon and life decades after the discovery of the resonance. + +Cosmic inflation + +Don Page criticized the entire theory of cosmic inflation as follows. He emphasized that initial conditions that made possible a thermodynamic arrow of time in a universe with a Big Bang origin, must include the assumption that at the initial singularity, the entropy of the universe was low and therefore extremely improbable. Paul Davies rebutted this criticism by invoking an inflationary version of the anthropic principle. While Davies accepted the premise that the initial state of the visible universe (which filled a microscopic amount of space before inflating) had to possess a very low entropy value—due to random quantum fluctuations—to account for the observed thermodynamic arrow of time, he deemed this fact an advantage for the theory. That the tiny patch of space from which our observable universe grew had to be extremely orderly, to allow the post-inflation universe to have an arrow of time, makes it unnecessary to adopt any "ad hoc" hypotheses about the initial entropy state, hypotheses other Big Bang theories require. + +String theory + +String theory predicts a large number of possible universes, called the "backgrounds" or "vacua". The set of these vacua is often called the "multiverse" or "anthropic landscape" or "string landscape". Leonard Susskind has argued that the existence of a large number of vacua puts anthropic reasoning on firm ground: only universes whose properties are such as to allow observers to exist are observed, while a possibly much larger set of universes lacking such properties go unnoticed. + +Steven Weinberg believes the anthropic principle may be appropriated by cosmologists committed to nontheism, and refers to that principle as a "turning point" in modern science because applying it to the string landscape "may explain how the constants of nature that we observe can take values suitable for life without being fine-tuned by a benevolent creator". Others—most notably David Gross but also Lubos Motl, Peter Woit, and Lee Smolin—argue that this is not predictive. Max Tegmark, Mario Livio, and Martin Rees argue that only some aspects of a physical theory need be observable and/or testable for the theory to be accepted, and that many well-accepted theories are far from completely testable at present. + +Jürgen Schmidhuber (2000–2002) points out that Ray Solomonoff's theory of universal inductive inference and its extensions already provide a framework for maximizing our confidence in any theory, given a limited sequence of physical observations, and some prior distribution on the set of possible explanations of the universe. + +Dimensions of spacetime + +There are two kinds of dimensions: spatial (bidirectional) and temporal (unidirectional). Let the number of spatial dimensions be N and the number of temporal dimensions be T. That N = 3 and T = 1, setting aside the compactified dimensions invoked by string theory and undetectable to date, can be explained by appealing to the physical consequences of letting N differ from 3 and T differ from 1. The argument is often of an anthropic character and possibly the first of its kind, albeit before the complete concept came into vogue. + +The implicit notion that the dimensionality of the universe is special is first attributed to Gottfried Wilhelm Leibniz, who in the Discourse on Metaphysics suggested that the world is "the one which is at the same time the simplest in hypothesis and the richest in phenomena". Immanuel Kant argued that 3-dimensional space was a consequence of the inverse square law of universal gravitation. While Kant's argument is historically important, John D. Barrow said that it "gets the punch-line back to front: it is the three-dimensionality of space that explains why we see inverse-square force laws in Nature, not vice-versa" (Barrow 2002:204). + +In 1920, Paul Ehrenfest showed that if there is only a single time dimension and more than three spatial dimensions, the orbit of a planet about its Sun cannot remain stable. The same is true of a star's orbit around the center of its galaxy. Ehrenfest also showed that if there are an even number of spatial dimensions, then the different parts of a wave impulse will travel at different speeds. If there are spatial dimensions, where k is a positive whole number, then wave impulses become distorted. In 1922, Hermann Weyl claimed that Maxwell's theory of electromagnetism can be expressed in terms of an action only for a four-dimensional manifold. Finally, Tangherlini showed in 1963 that when there are more than three spatial dimensions, electron orbitals around nuclei cannot be stable; electrons would either fall into the nucleus or disperse. + +Max Tegmark expands on the preceding argument in the following anthropic manner. If T differs from 1, the behavior of physical systems could not be predicted reliably from knowledge of the relevant partial differential equations. In such a universe, intelligent life capable of manipulating technology could not emerge. Moreover, if T > 1, Tegmark maintains that protons and electrons would be unstable and could decay into particles having greater mass than themselves. (This is not a problem if the particles have a sufficiently low temperature.) Lastly, if N < 3, gravitation of any kind becomes problematic, and the universe would probably be too simple to contain observers. For example, when N < 3, nerves cannot cross without intersecting. Hence anthropic and other arguments rule out all cases except N = 3 and T = 1, which describes the world around us. + +On the other hand, in view of creating black holes from an ideal monatomic gas under its self-gravity, Wei-Xiang Feng showed that (3+1)-dimensional spacetime is the marginal dimensionality. Moreover, it is the unique dimensionality that can afford a "stable" gas sphere with a "positive" cosmological constant. However, a self-gravitating gas cannot be stably bound if the mass sphere is larger than ~1021 solar masses, due to the small positivity of the cosmological constant observed. + +In 2019, James Scargill argued that complex life may be possible with two spatial dimensions. According to Scargill, a purely scalar theory of gravity may enable a local gravitational force, and 2D networks may be sufficient for complex neural networks. + +Metaphysical interpretations +Some of the metaphysical disputes and speculations include, for example, attempts to back Pierre Teilhard de Chardin's earlier interpretation of the universe as being Christ centered (compare Omega Point), expressing a creatio evolutiva instead the elder notion of creatio continua. From a strictly secular, humanist perspective, it allows as well to put human beings back in the center, an anthropogenic shift in cosmology. Karl W. Giberson has laconically stated that + +William Sims Bainbridge disagreed with de Chardin's optimism about a future Omega point at the end of history, arguing that logically, humans are trapped at the Omicron point, in the middle of the Greek alphabet rather than advancing to the end, because the universe does not need to have any characteristics that would support our further technical progress, if the anthropic principle merely requires it to be suitable for our evolution to this point. + +The anthropic cosmological principle +A thorough extant study of the anthropic principle is the book The anthropic cosmological principle by John D. Barrow, a cosmologist, and Frank J. Tipler, a cosmologist and mathematical physicist. This book sets out in detail the many known anthropic coincidences and constraints, including many found by its authors. While the book is primarily a work of theoretical astrophysics, it also touches on quantum physics, chemistry, and earth science. An entire chapter argues that Homo sapiens is, with high probability, the only intelligent species in the Milky Way. + +The book begins with an extensive review of many topics in the history of ideas the authors deem relevant to the anthropic principle, because the authors believe that principle has important antecedents in the notions of teleology and intelligent design. They discuss the writings of Fichte, Hegel, Bergson, and Alfred North Whitehead, and the Omega Point cosmology of Teilhard de Chardin. Barrow and Tipler carefully distinguish teleological reasoning from eutaxiological reasoning; the former asserts that order must have a consequent purpose; the latter asserts more modestly that order must have a planned cause. They attribute this important but nearly always overlooked distinction to an obscure 1883 book by L. E. Hicks. + +Seeing little sense in a principle requiring intelligent life to emerge while remaining indifferent to the possibility of its eventual extinction, Barrow and Tipler propose the final anthropic principle (FAP): Intelligent information-processing must come into existence in the universe, and, once it comes into existence, it will never die out. + +Barrow and Tipler submit that the FAP is both a valid physical statement and "closely connected with moral values". FAP places strong constraints on the structure of the universe, constraints developed further in Tipler's The Physics of Immortality. One such constraint is that the universe must end in a Big Crunch, which seems unlikely in view of the tentative conclusions drawn since 1998 about dark energy, based on observations of very distant supernovas. + +In his review of Barrow and Tipler, Martin Gardner ridiculed the FAP by quoting the last two sentences of their book as defining a completely ridiculous anthropic principle (CRAP): + +Reception and controversies +Carter has frequently regretted his own choice of the word "anthropic", because it conveys the misleading impression that the principle involves humans specifically, rather than intelligent observers in general. Others have criticised the word "principle" as being too grandiose to describe straightforward applications of selection effects. + +A common criticism of Carter's SAP is that it is an easy deus ex machina that discourages searches for physical explanations. To quote Penrose again: "[I]t tends to be invoked by theorists whenever they do not have a good enough theory to explain the observed facts." + +Carter's SAP and Barrow and Tipler's WAP have been dismissed as truisms or trivial tautologies—that is, statements true solely by virtue of their logical form and not because a substantive claim is made and supported by observation of reality. As such, they are criticized as an elaborate way of saying, "If things were different, they would be different", which is a valid statement, but does not make a claim of some factual alternative over another. + +Critics of the Barrow and Tipler SAP claim that it is neither testable nor falsifiable, and thus is not a scientific statement but rather a philosophical one. The same criticism has been leveled against the hypothesis of a multiverse, although some argue that it does make falsifiable predictions. A modified version of this criticism is that humanity understands so little about the emergence of life, especially intelligent life, that it is effectively impossible to calculate the number of observers in each universe. Also, the prior distribution of universes as a function of the fundamental constants is easily modified to get any desired result. + +Many criticisms focus on versions of the strong anthropic principle, such as Barrow and Tipler's anthropic cosmological principle, which are teleological notions that tend to describe the existence of life as a necessary prerequisite for the observable constants of physics. Similarly, Stephen Jay Gould, Michael Shermer, and others claim that the stronger versions of the anthropic principle seem to reverse known causes and effects. Gould compared the claim that the universe is fine-tuned for the benefit of our kind of life to saying that sausages were made long and narrow so that they could fit into modern hotdog buns, or saying that ships had been invented to house barnacles. These critics cite the vast physical, fossil, genetic, and other biological evidence consistent with life having been fine-tuned through natural selection to adapt to the physical and geophysical environment in which life exists. Life appears to have adapted to the universe, and not vice versa. + +Some applications of the anthropic principle have been criticized as an argument by lack of imagination, for tacitly assuming that carbon compounds and water are the only possible chemistry of life (sometimes called "carbon chauvinism", see also alternative biochemistry). The range of fundamental physical constants consistent with the evolution of carbon-based life may also be wider than those who advocate a fine-tuned universe have argued. For instance, Harnik et al. propose a Weakless Universe in which the weak nuclear force is eliminated. They show that this has no significant effect on the other fundamental interactions, provided some adjustments are made in how those interactions work. However, if some of the fine-tuned details of our universe were violated, that would rule out complex structures of any kind—stars, planets, galaxies, etc. + +Lee Smolin has offered a theory designed to improve on the lack of imagination that anthropic principles have been accused of. He puts forth his fecund universes theory, which assumes universes have "offspring" through the creation of black holes whose offspring universes have values of physical constants that depend on those of the mother universe. + +The philosophers of cosmology John Earman, Ernan McMullin, and Jesús Mosterín contend that "in its weak version, the anthropic principle is a mere tautology, which does not allow us to explain anything or to predict anything that we did not already know. In its strong version, it is a gratuitous speculation". A further criticism by Mosterín concerns the flawed "anthropic" inference from the assumption of an infinity of worlds to the existence of one like ours: + +See also + + (discussing the anthropic principle) + + (an immediate precursor of the idea) + + + + + + + + + + + + + + + (work of Alejandro Jenkins) + +Notes + +Footnotes + +References + + + 5 chapters available online. + + + + + + Stenger, Victor J. (1999), "Anthropic design," The skeptical inquirer 23 (August 31, 1999): 40–43 + Mosterín, Jesús (2005). "Anthropic explanations in cosmology." In P. Háyek, L. Valdés and D. Westerstahl (ed.), Logic, methodology and philosophy of science, Proceedings of the 12th international congress of the LMPS. London: King's college publications, pp. 441–473. . + + A simple anthropic argument for why there are 3 spatial and 1 temporal dimensions. + + Shows that some of the common criticisms of anthropic principle based on its relationship with numerology or the theological design argument are wrong. + +External links + + Nick Bostrom: web site devoted to the anthropic principle. + Friederich, Simon. Fine-tuning, review article of the discussion about fine-tuning, highlighting the role of the anthropic principles. + Gijsbers, Victor. (2000). Theistic anthropic principle refuted – Positive atheism magazine. + Chown, Marcus, Anything Goes, New scientist, 6 June 1998. On Max Tegmark's work. + Stephen Hawking, Steven Weinberg, Alexander Vilenkin, David Gross and Lawrence Krauss: Debate on anthropic reasoning Kavli-CERCA conference video archive. + Sober, Elliott R. 2009, "Absence of evidence and evidence of absence – Evidential transitivity in connection with fossils, fishing, fine-tuning, and firing squads." Philosophical Studies, 2009, 143: 63–90. + "Anthropic coincidence" – The anthropic controversy as a segue to Lee Smolin's theory of cosmological natural selection. + Leonard Susskind and Lee Smolin debate the anthropic principle. + Debate among scientists on arxiv.org. + Evolutionary probability and fine tuning + Benevolent design and the anthropic principle at MathPages + Critical review of "The privileged planet" + The anthropic principle – a review. + Berger, Daniel, 2002, "An impertinent résumé of the Anthropic cosmological principle. " A critique of Barrow & Tipler. + Jürgen Schmidhuber: Papers on algorithmic theories of everything and the anthropic principle's lack of predictive power. + Paul Davies: Cosmic jackpot – Interview about the anthropic principle (starts at 40 min), 15 May 2007. + + +Astronomical hypotheses +Concepts in epistemology +Physical cosmology +Principles +Religion and science +The Australian Army is the principal land warfare force of Australia, a part of the Australian Defence Force (ADF) along with the Royal Australian Navy and the Royal Australian Air Force. The Army is commanded by the Chief of Army (CA), who is subordinate to the Chief of the Defence Force (CDF) who commands the ADF. The CA is also directly responsible to the Minister for Defence, with the Department of Defence administering the ADF and the Army. + +Formed in 1901, as the Commonwealth Military Forces, through the amalgamation of the colonial forces of Australia following the Federation of Australia. Although Australian soldiers have been involved in a number of minor and major conflicts throughout Australia's history, only during the Second World War has Australian territory come under direct attack. + +The Australian Army was initially composed almost completely of part–time soldiers, where the vast majority were in units of the Citizens Military Force (CMF or Militia) (1901–1980) during peacetime, with limits set on the regular Army. Since all reservists were barred from forcibly serving overseas, volunteer expeditionary forces (1st AIF, ANMEF, 2nd AIF) were formed to enable the Army to send large numbers of soldiers to serve overseas during periods of war. This period lasted from federation until post–1947, when a standing peacetime regular army was formed and the Australian Army Reserve (1980–present) began to decline in importance. + +During its history, the Australian Army has fought in a number of major wars, including the Second Boer War, the First and Second World Wars, Korean War, Malayan Emergency, Indonesia-Malaysia Confrontation, Vietnam War, and more recently in Afghanistan and Iraq. Since 1947, the Australian Army has also been involved in many peacekeeping operations, usually under the auspices of the United Nations. Today, it participates in multilateral and unilateral military exercises and provides emergency disaster relief and humanitarian aid in response to domestic and international crises. + +History + +Formation + +Formed in March 1901, following federation, the Australian Army initially consisted of the six, disbanded and separate, colonial military forces' land components. Due to the Army being continuation of the colonial armies, it became immediately embroiled in conflict as contingents had been committed to fight for the United Kingdom of Great Britain and Ireland in the Second Boer War. The Army gained command of these contingents and even supplied federal units to reinforce their commitment at the request of the British government. + +The Defence Act 1903, established the operation and command structure of the Australian Army. In 1911, the Universal Service Scheme was implemented, introducing conscription for the first time in Australia, with males aged 14–26 assigned into cadet and CMF units; though the scheme did not prescribe or allow overseas service outside the states and territories of Australia. This restriction would be primarily, and continually, bypassed through the process of raising separate volunteer forces until the mid-20th century; this solution was not without its drawbacks, as it caused logistical dilemmas. + +World War I + +After the declaration of war on the Central Powers, the Australian Army raised the all volunteer First Australian Imperial Force (AIF) which had an initial recruitment of 52,561 out of a promised 20,000 men. A smaller expeditionary force, the Australian Naval and Military Expeditionary Force (ANMEF), dealt with the issue of the German Pacific holdings. ANMEF recruitment began on 10 August 1914, and operations started 10 days later. On 11 September, the ANMEF landed at Rabaul to secure German New Guinea, with no German outposts in the Pacific left by November 1914. During the AIF's preparations to depart Australia, the Ottoman Empire joined the Central Powers; thereby receiving declarations of war from the Allies of World War I in early November 1914. + +After initial recruitment and training, the AIF departed for Egypt where they underwent further preparations, and where the Australian and New Zealand Army Corps (ANZAC) was formed. Their presence in Egypt was due to the planned Gallipoli campaign, an invasion of the Ottoman Empire via Gallipoli. On 25 April, the AIF landed at ANZAC Cove, which signaled the start of Australia's contribution to the campaign. Following little initial success, fighting quickly devolved into trench warfare, which precipitated a stalemate. On 15 December 1915, after eight months of fighting, the evacuation of Gallipoli commenced; it was completed 5 days later with no casualties recorded. After regrouping in Egypt, the AIF was split into two groups and further expanded with reinforcements. This division would see a majority of the Australian Light Horse fight the Ottomans in Arabia and the Levant, whereas +the rest of the AIF would go to the Western Front. + +Western Front + +The AIF arrived in France with the 1st, 2nd, 4th and 5th Divisions; which comprised, in part, I ANZAC Corps and, in full, II ANZAC Corps. The 3rd Division would not arrive until November 1916, as it underwent training in England after its transfer from Australia. In July 1916, the AIF commenced operations with the Battle of the Somme, and more specifically with the Attack at Fromelles. Soon after, the 1st, 2nd and 4th Divisions became tied down in actions at the Battle of Pozières and Mouquet Farm. In around six weeks, the operations caused 28,000 Australian casualties. Due to these losses and pressure from the United Kingdom to maintain the AIF's manpower, Prime Minister Billy Hughes introduced the first conscription plebiscite. It was defeated by a narrow margin and created a bitter divide on the issue of conscription throughout the 20th century. + +Following the German withdrawal to the Hindenburg Line in March 1917, which was better defended and eased manpower restraints, the first Australian assault on the Hindenburg Line occurred on 11 April 1917 with the First Battle of Bullecourt. On 20 September, the Australian contingent joined the Third Battle of Ypres with the Battle of Menin Road, and continued on to fight in the Battle of Polygon Wood, which lasted until 3 October; in total, these tow operations cost roughly 11,000 in Australian casualties. Until 15 November 1917, multiple attacks at the Battle of Broodseinde Ridge and the Battle of Passchendaele occurred, but, failed to take their objectives following the start of the rain and subsequent muddying of the fields. + +On 21 March 1918, the Germans attempted a breakout through the Michael Offensive, which was part of the much larger German spring offensive; the AIF suffered 15,000 casualties due to this effort. During this operation, Australian troops conducted a series of local defences and offensives to hold and retake Villers–Brettoneux over the period 4 to 25 April 1918. After the cessation of offensives by the German Army, the Australian Corps began participating in "Peaceful penetration" operations, which were localised raids designed to harass and gain small tracts of territory; these proved so effective that several major operational objectives were captured. + +On 4 July 1918, the Battle of Hamel saw the first successful use of tanks alongside Australians, with the battleplan of John Monash completed three minutes over the planned 90 minute operation. Following this success, the Battle of Amiens was launched on 8 August 1918, in conjunction with the Canadian Corps and the British III Corps, and concluded on 12 August 1918; General Erich Ludendorff described it as "the black day of the German Army". On 29 August 1918, following territorial advances and pursuits, the AIF attacked Pèronne and subsequently initiated the Battle of Mont St Quentin. Another operation around Épehy was planned for 18 September 1918, which aimed to retake the British trenches and, potentially, capture their most ambitious objective of the Hindenburg's outpost line – which they achieved. + +Following news of a three-month furlough for certain soldiers, seven AIF battalions were disbanded; consequently, members of these battalions mutinied. Soon after the penetration of the Hindenburg Line, plans for the breakthrough of the main trench, with the Australian Corps as the vanguard, were completed. However, due to manpower issues, only the 3rd and 5th Divisions participated, with the American Expeditionary Forces' 27th and 30th Divisions given as reinforcements. On 29 September, following a three day long bombardment, the Battle of the Hindenburg Line commenced, wherein the corps attacked and captured more of the line. On 5 October 1918, after furious fighting, the Australian Corps was withdrawn from the front, as the entire corps had been operating continuously since 8 August 1918. They would not return to the battlefield, as Germany signed the Armistice of 11 November 1918 that ultimately ended the war on the Western Front. + +Middle East + +The Australian mounted units, composed of the ANZAC Mounted Division and eventually the Australian Mounted Division, participated in the Sinai and Palestine campaign. They were originally stationed there to protect the Suez Canal from the Turks, and following the threat of its capture passing, they started offensive operations and helped in the re-conquest of the Sinai Desert. This was followed by the Battles of Gaza, wherein on the 31 October 1917 the 4th and 12th Light Horse took Beersheba through the last charge of the Light Horse. They continued on to capture Jerusalem on 10 December 1917 and then eventually Damascus on 1 October 1918 whereby, a few days later on 10 October 1918, the Ottoman Empire surrendered. + +Interbellum + +Repatriation efforts were implemented between the armistice and the end of 1919, which occurred after the disbandment of the Australian Imperial Force. In 1921, CMF units were renumbered to that of the AIF, to perpetuate the honours and numerical identities of the units involved in WW1. During this period there was a complacency towards matters of defence, due to the devastating effects of the previous war on the Australian psyche. Following the election of Prime Minister James Scullin in 1929, two events occurred that substantially affected the armed forces: conscription was abolished and the economic effects of the Great Depression started to be felt in Australia. The economic ramifications of the depression led to decisions that decreased defence expenditure and manpower for the army. Since conscription was repealed, to reflect the new volunteer nature of the Citizens Forces, the CMF was renamed to the Militia. + +World War II + +Following the declaration of war on Nazi Germany and her allies by the United Kingdom, and the subsequent confirmation by Prime Minister Robert Menzies on 3 September 1939, the Australian Army raised the Second Australian Imperial Force, a 20,000-strong volunteer expeditionary force, which initially consisted of the 6th Division; later increased to include the 7th and 9th Divisions, alongside the 8th Division which was sent to Singapore. In October 1939, compulsory military training recommenced for unmarried men aged 21, who had to complete three months of training. + +The 2nd AIF commenced its first operations in North Africa with Operation Compass, that began with the Battle of Bardia. This was followed by supplying Australian units to defend against the Axis in the Battle of Greece. After the evacuation of Greece, Australian troops took part in the Battle of Crete which, though more successful, still failed and another withdrawal was ordered. During the Greek Campaign, the Allies were pushed back to Egypt and the Siege of Tobruk began. Tobruk's primary defence personnel were Australians of the 9th Division; the so-called 'Rats of Tobruk'. Additionally, the AIF participated in the Syria–Lebanon campaign. The 9th Division fought in the First and Second Battle of El Alamein before also being shipped home to fight the Japanese. + +Pacific + +In December 1941, following the Bombing of Pearl Harbour, Australia declared war on Japan. Consequently, the AIF was requested to return home, as the subsequent rapid conquest of Southeast Asia extremely concerned Australian policymakers, and the militia was mobilised. After the Fall of Singapore, and the consequent capture of the entire 8th Division as POWs, this concern only grew. These events hastened the relief of the Rats of Tobruk, while the other divisions were immediately recalled to reinforce New Guinea. General conscription was reintroduced, though service was again limited to Australian possessions, which caused tension between the AIF and Militia. This was in addition to the CMF's perceived inferior fighting ability, with these grievances earning the Militia their nicknames of "koalas" and "chocos" or "chocolate soldiers". + +The Imperial Japanese Navy's failure in the Battle of the Coral Sea, was the impetus for the Imperial Japanese Army to try to capture Port Moresby via the Owen Stanley Range. On 21 July 1942, the Japanese began the Kokoda Campaign after landing at Gona; attempts to defeat them by Australian battalions were met with eventual success. Resultant offensive operations concluded with the Japanese being driven out of New Guinea entirely. In parallel with these defences, the Battle of Milne Bay was waged, and when the Japanese were repulsed, it was considered their first significant reversal for the war. In November 1942, the campaign ended after the Japanese withdrawal, with Australian advances leading to the Battle of Buna–Gona. + +In early 1943, the Salamaua–Lae campaign began, with operations against the entrenched Japanese aimed towards recapturing the eponymous towns. This culminated in the capture of Lae, held by the 7th Division in early September 1943, from a successful combined amphibious landing at Lae and an airborne landing at Nadzab. The seaborne assault was notable as it was the first large–scale amphibious operation since Gallipoli. Subsequently, Salamaua was taken days later on 11 September 1943, by a separate joint Australia–US attack. The Battle of Lae was additionally part of the wider Huon Peninsula campaign. Following Lae's capture, the Battle of Finschhafen commenced with a relatively swift control of objectives, with subsequent Japanese counterattacks beaten off. On 17 November 1943, a major offensive that began with the Battle of Sattelberg, continued with the Battle of Wareo, and concluded with the Battle of Sio on 15 January 1944, was unleashed. The momentum of this advance was continued by the 8th Brigade, as they pursued the enemy in retreat, which culminated with the Battle of Madang. + +In mid-1944, Australian forces took over the garrisoning of Torokina from the US with this changeover giving Australian command responsibility over the Bougainville campaign. Soon after arriving in November of the same year, the commander of II Corps, Lieutenant-General Stanley Savige, began an offensive to retake the island with the 3rd Division alongside the 11th and 23rd Brigades. The campaign lasted until the Japanese surrender, with controversy surrounding its little apparent significance to the war's conclusion, and the number of casualties incurred; this was one of Australia's most costliest campaigns in the Second World War. + +In October 1944, Australian participation in the Aitape–Wewak campaign began with the replacement of US forces at Aitape with the Australian 6th Division. US forces had previously captured the position, and had held it passively, though Australian command found this unsuitable. On 2 November 1944, the 2/6th Cavalry Commando Regiment was tasked with patrolling the area, wherein minor engagements were reported. In early December, the commandos were sent inland to establish access to the Torricelli Range, while the 19th Brigade handled patrolling, consequently, the amount of fierce fighting and territory secured increased. Following this success, thought was given for the capture of Maprik and Wewak, though supply became a major issue in this period. On 10 February 1945, the campaign's major offensive was underway, which resulted in both falling in quick succession on 22 April 1945. Smaller operations to secure the area continued, and all significant actions ceased by July. + +The Borneo campaign was a series of three distinct amphibious operations that were undertaken by the 7th and 9th Divisions. The campaign began with the Battle of Tarakan on 1 May 1945, followed six weeks later by the Battle of Labuan, and concluded with the Battle of Balikpapan. The purpose of capturing Tarakan was to establish airfields, and the island was taken seven weeks following the initial amphibious landing. On 10 June 1945, the operation at Labuan commenced, and was tasked to secure resources and a naval base, and would continue until Japan's surrender. On 1 July 1945, the Balikpapan engagement commenced, with all its major objectives being acquired by war's end; this operation remains the largest amphibious operation undertaken by Australian forces, with 33,000 Australian servicemen participating. On 15 August 1945, Japan surrendered, ending the Second World War. + +Cold War + +Korean War + +After the surrender of Japan, Australia provided a contingent to the British Commonwealth Occupation Force (BCOF) which included the 34th Brigade. The units that composed the brigade would eventually become the nucleus of the regular army, with the battalions and brigade being renumbered to reflect this change. Following the start of the Korean War, the Australian Army committed troops to fight against the North Korean forces; the units came from the Australian contribution to BCOF. The 3rd Battalion, Royal Australian Regiment (3RAR) arrived in Pusan on 28 September 1950. Australian troop numbers would increase and continue to be deployed up until the armistice, with 3RAR being eventually joined by the 1st Battalion, Royal Australian Regiment (1RAR). For a brief period, between 1951 and 1959, the Menzies Government reinstituted conscription and compulsory military training with the National Service Scheme, which required all males of eighteen years of age to serve for specified period in either the Australian Regular Army (ARA) or CMF. + +Malayan Emergency + +The Australian military entered the Malayan Emergency (1948–1960) in October 1955, committing the 2nd Battalion, Royal Australian Regiment (2RAR) to fight alongside Commonwealth forces. The 2RAR fought against the Malayan National Liberation Army (MNLA), a communist led guerrilla army whose goal was to turn Malaya into a socialist republic, and whose leaders had previously been trained and funded by Britain to resist the Japanese occupation of Malaya. Australian military operations in Malaya consisted of patrolling actions and guarding infrastructure, though they rarely saw combat as the emergency was nearly over by the time of their deployment. All three original Royal Australian Regiment battalions would complete at least one tour before the end of operations. In August 1963, Australia ended deployments to Malaya, three years after the emergency's official end. + +Indonesia–Malaysia confrontation + +In 1962, the Borneo Confrontation began, due to Indonesia's opposition to the formation of Malaysia. It was an undeclared war that entailed a series of border conflicts between Indonesian-backed forces and British–Malaysian allies. Initial Australian support in the conflict began, and continued throughout, with the training and supply of Malaysian troops; Australian soldiers only saw combat during defensive operations. In January 1965, permission was granted for the deployment of 3RAR, with extensive operations conducted in Sarawak from March until their withdrawal in July 1965. The subsequent deployment of 4th Battalion, Royal Australian Regiment (4RAR), in April 1966, was less intensive, with the battalion withdrawn in August. This is not to mention the efforts of several other corps and units in the conflict. + +Vietnam War + +The Australian Army commenced its involvement in the Vietnam War by sending military advisors in 1962, which was then increased by sending in combat troops, specifically 1RAR, on 27 May 1965. Just before the official start of hostilities, the Australian Army was augmented with the reintroduction of conscription, which was based on a 'birthday ballot' selection process for all registered 20-year-old males. These men were required to register, unless they gave a legitimate reason for their exemption, else they faced penalties. This scheme would prove to be one of the most controversial implementations of conscription in Australia, with large protests against its adoption. + +In March 1966, the Australian Army increased its commitment again with the replacement of 1RAR with the 1st Australian Task Force, a force in which all nine battalions of the Royal Australian Regiment would serve. One of the heaviest actions of the war occurred in August 1966, with the Battle of Long Tan, wherein D Company, 6th Battalion, Royal Australian Regiment (6RAR) successfully fended off an enemy force, estimated at 2,000 men, for four hours. In 1968, Australian forces defended against the Tet Offensive, a Viet Cong military operation, and repulsed them with few casualties. The contribution of personnel to the war was gradually wound down, starting in late-1970 and ending in 1972; the official declaration of the end of Australia's involvement in the war was made on 11 January 1973. + +Activities in Africa +Following the Vietnam War, there was a significant hiatus of operational activity by the Australian Army. In late 1979, in the largest deployment of the decade, the Army committed 151 troops to the Commonwealth Monitoring Force, which monitored the transition of Rhodesia to universal suffrage. A decade later in 1989, Australia deployed 300 army engineer personnel as the Australian contribution to the United Nations Transition Assistance Group in Namibia. The mission helped transition the country to independence from South African control. + +Recent history (1990–present) + +Peacekeeping +Following the invasion of Kuwait by Iraq in August 1990, a coalition of countries sponsored by the United Nations Security Council, of which Australia was a part, gave a deadline for Iraq to withdraw from Kuwait of the 15 January 1991. Iraq refused to retreat and thus full conflict and the Gulf War began two days later on 17 January 1991. In January 1993, the Australian Army deployed 26 personnel on an ongoing rotational basis to the Multinational Force and Observers (MFO), as part of a non-United Nations peacekeeping organisation that observes and enforces the peace treaty between Israel and Egypt. + +Australia's largest peacekeeping deployment began in 1999 with the International Force for East Timor, while other ongoing operations include peacekeeping in the Sinai (as part of MFO), and the United Nations Truce Supervision Organization (as part of Operation Paladin since 1956). Humanitarian relief after the 2004 Indian Ocean earthquake in Aceh Province, Indonesia, Operation Sumatra Assist, ended on 24 March 2005. + +Afghanistan and Iraq + +Following the 11 September 2001 terrorist attacks, Australia promised troops to any military operations that the US commenced in response to the attacks. Subsequently, the Australian Army committed combat troops to Afghanistan in Operation Slipper. This combat role continued until the end of 2013 when it was replaced by a training contingent operating under Operation Highroad until 2021. + +After the Gulf War the UN imposed heavy restrictions on Iraq to stop them producing any Weapon of mass destruction. In the early 21st century, the US accused Iraq of possessing these weapons and promoted unsubstantiated allegations, and requested that the UN invade the country in response, a motion which Australia supported. The UN denied this motion, however, it did not stop a coalition, that Australia joined, invading the country; thus starting the Iraq War on 19 March 2003. + +Between April 2015 and June 2020, the Army deployed a 300-strong element to Iraq, designated as Task Group Taji, as part of Operation Okra. In support of a capacity building mission, Task Group Taji's main role was to provide training to Iraqi forces, during which Australian troops have served alongside counterparts from New Zealand. + +In 2020 an investigation of allegations of war crimes committed during Australian military operations in Afghanistan was concluded with the release of the Brereton Report. The report identified 25 ADF personnel that were involved directly or indirectly in the murder of 39 civilians and prisoners, with 19 referred to the Australian Federal Police to be criminally investigated. A 'warrior culture' in the SAS was specifically criticised with investigators 'frustrated by outright deceit by those who knew the truth and, not infrequently, misguided resistance to inquiries and investigations by their superiors'. + +Organisation + +1st Division +Beginning 1 July 2023, the division was renamed the 1st (Australian) Division. The 1st, 3rd and 7th Brigades were placed under the direct control of the division's headquarters. This reform aimed to improve the connections between the divisional headquarters and the brigades it commands during deployments. + + 1 Brigade – Light Combat Brigade based in Darwin. + + 3 Brigade – Armoured Combat Brigade based in Townsville. + + 7 Brigade – Motorised Combat Brigade based in Brisbane. + +Forces Command +Forces Command controls for administrative purposes all non-combat assets of the Australian Army. It's focus is on unifying all training establishments to create a base for scaling and mobilisation: + 2 Brigade – Health Brigade based across Australia. + 6 Brigade (CS&ISTAR) – Mixed brigade based in Sydney. + 8 Brigade – training brigade with units around Australia. + 17 Sustainment Brigade – Logistic brigade based in Sydney. + +Additionally, Forces Command includes the following training establishments: + Army Recruit Training Centre at Kapooka, NSW; + Royal Military College, Duntroon in the ACT; + Combined Arms Training Centre at Puckapunyal, Victoria; + Army Logistic Training Centre at Bonegilla and Bandiana, Victoria; + Defence Command Support Training Centre at Macleod, Victoria + +2nd Division +Administers the reserve forces from its headquarters located in Sydney. + + 4 Brigade – based in Victoria and Tasmania. +5 Brigade – based in New South Wales. +9 Brigade – Integrated Combat Brigade based in South Australia. + 11 Brigade – based in Queensland. + 13 Brigade – based in Western Australia. + +Aviation +Army Aviation Command is responsible for the Australian Army's helicopters and training, aviation safety and unmanned aerial vehicles (UAV). Army Aviation Command comprises: + 16 Aviation Brigade – brigade based in Gallipoli Barracks at Enoggera, Brisbane. + Army Aviation Training Centre at Oakey, Queensland + +Special Forces +Special Operations Command is a command formation of equal status to the other commands in the ADF and includes all of Army's special forces units. Special Operations Command comprises: + Special Forces Group - a brigade-level headquarters. + +Colours, standards and guidons + +Infantry, and some other combat units of the Australian Army carry flags called the King's Colour and the Regimental Colour, known as "the Colours". Armoured units carry Standards and Guidons – flags smaller than Colours and traditionally carried by Cavalry, Lancer, Light Horse and Mounted Infantry units. The 1st Armoured Regiment is the only unit in the Australian Army to carry a Standard, in the tradition of heavy armoured units. Artillery units' guns are considered to be their Colours, and on parade are provided with the same respect. Non-combat units (combat service support corps) do not have Colours, as Colours are battle flags and so are only available to combat units. As a substitute, many have Standards or Banners. Units awarded battle honours have them emblazoned on their Colours, Standards and Guidons. They are a link to the unit's past and a memorial to the fallen. Artillery do not have Battle Honours – their single Honour is "Ubique" which means "Everywhere" – although they can receive Honour Titles. + +The Army is the guardian of the National Flag and as such, unlike the Royal Australian Air Force, does not have a flag or Colours. The Army, instead, has a banner, known as the Army Banner. To commemorate the centenary of the Army, the Governor General Sir William Deane, presented the Army with a new Banner at a parade in front of the Australian War Memorial on 10 March 2001. The banner was presented to the Regimental Sergeant Major of the Army (RSM-A), Warrant Officer Peter Rosemond. + +The Army Banner bears the Australian Coat of Arms on the obverse, with the dates "1901–2001" in gold in the upper hoist. The reverse bears the "rising sun" badge of the Australian Army, flanked by seven campaign honours on small gold-edged scrolls: South Africa, World War I, World War II, Korea, Malaya-Borneo, South Vietnam, and Peacekeeping. The banner is trimmed with gold fringe, has gold and crimson cords and tassels, and is mounted on a pike with the usual British royal crest finial. + +Personnel + +Strength +As of June 2022 the Army had 28,387 permanent (regular) members and 20,742 reservists (part-time); all of whom are volunteers. As of June 2022, women made up 15.11% of the Army, with a target set for 18% 2025. Gender based restrictions for frontline combat or training roles were lifted in January 2013. Also as of June 2022, Indigenous Australians made up 3.7% of the Army. + +Rank and insignia + +The ranks of the Australian Army are based on the ranks of the British Army, and carry mostly the same actual insignia. For officers the ranks are identical except for the shoulder title "Australia". The Non-Commissioned Officer insignia are the same up until Warrant Officer, where they are stylised for Australia (for example, using the Australian, rather than the British coat of arms). +The ranks of the Australian Army are as follows: + +Uniforms and Dress + +The Australian Army uniforms are detailed in the Australian Army Dress Manual and are grouped into nine general categories, each ranging from ceremonial dress, to general duties dress, to battle dress (in addition there are a number of special categories specific to uniforms that are only worn when posted to specific locations, like ADFA or RMC-D), these are further divided into individual 'Dress Orders' denoted by alphabetical suffixes that detail the specific items of clothing, embellishment and accoutrements, i.e. Dress Order No. 1A - 'Ceremonial Parade Service Dress', Dress Order No. 2G - 'General Duty Office Dress', Dress Order No 4C ‘Combat Dress (AMCU)’ . The slouch hat or beret are the regular service and general duties hat, while the field hat, or combat helmet is for use in the field, while training, on exercise, or on operations. In Dec 2013 the Chief of Army reversed a previous ban on berets as general duties headwear for all personnel except Special Forces personnel (SASR, CDO Regiments). Australian Multi-cam Camouflage Uniform is the camouflage pattern for Australian Army camouflage uniforms, and was introduced in 2014, replacing the Disruptive Pattern Camouflage Uniform (DPCU), and Disruptive Pattern Desert Uniform (DPDU) for all Australian Army orders of dress. + +Equipment + +Firearms and artillery + +Vehicles + +Support + +Aircraft + +Bases + +The Army's operational headquarters, Forces Command, is located at Victoria Barracks in Sydney. The Australian Army's three regular brigades are based at Robertson Barracks near Darwin, Lavarack Barracks in Townsville, and Gallipoli Barracks in Brisbane. The Deployable Joint Force Headquarters is also located at Gallipoli Barracks. + +Other important Army bases include the Army Aviation Centre near Oakey, Queensland, Holsworthy Barracks near Sydney, Lone Pine Barracks in Singleton, New South Wales and Woodside Barracks near Adelaide, South Australia. The SASR is based at Campbell Barracks Swanbourne, a suburb of Perth, Western Australia. + +Puckapunyal, north of Melbourne, houses the Australian Army's Combined Arms Training Centre, Land Warfare Development Centre, and three of the five principal Combat Arms schools. Further barracks include Steele Barracks in Sydney, Keswick Barracks in Adelaide, and Irwin Barracks at Karrakatta in Perth. Dozens of Australian Army Reserve depots are located across Australia. + +Australian Army Journal +Since June 1948, the Australian Army has published its own journal titled the Australian Army Journal. The journal's first editor was Colonel Eustace Keogh, and initially, it was intended to assume the role that the Army Training Memoranda had filled during the Second World War, although its focus, purpose, and format has shifted over time. Covering a broad range of topics including essays, book reviews and editorials, with submissions from serving members as well as professional authors, the journal's stated goal is to provide "...the primary forum for Army's professional discourse... [and]... debate within the Australian Army... [and improve the]... intellectual rigor of that debate by adhering to a strict and demanding standard of quality". In 1976, the journal was placed on hiatus as the Defence Force Journal began publication; however, publishing of the Australian Army Journal began again in 1999 and since then the journal has been published largely on a quarterly basis, with only minimal interruptions. + +See also + + Australian Defence Force ranks and insignia + Australian military slang + Battle and theatre honours of the Australian Army + Conscription in Australia + List of Australian Army units + List of Australian military memorials +List of military weapons of Australia +Army (newspaper) + +References + +Citations + +Notes + +Bibliography + +Further reading + +External links + + + Australian Army Dress Manual - AL5 (2013) + + +1901 establishments in Australia +Cold War history of Australia +The American Registry for Internet Numbers (ARIN) is the regional Internet registry for the United States, Canada, and many Caribbean and North Atlantic islands. ARIN manages the distribution of Internet number resources, including IPv4 and IPv6 address space and AS numbers. ARIN opened for business on December 22, 1997 after incorporating on April 18, 1997. ARIN is a nonprofit corporation with headquarters in Chantilly, Virginia, United States."Chantilly CDP, Virginia ." U.S. Census Bureau. Retrieved on September 16, 2009. + +ARIN is one of five regional Internet registries in the world. Like the other regional Internet registries, ARIN: + +Provides services related to the technical coordination and management of Internet number resources +Facilitates policy development by its members and stakeholders +Participates in the international Internet community +Is a nonprofit, community-based organization +Is governed by an executive board elected by its membership + +Services +ARIN provides services related to the technical coordination and management of Internet number resources. The nature of these services is described in ARIN's mission statement:Applying the principles of stewardship, ARIN, a nonprofit corporation, allocates Internet Protocol resources; develops consensus-based policies; and facilitates the advancement of the Internet through information and educational outreach.These services are grouped in three areas: Registration, Organization, and Policy Development. + +Registration services +Registration services pertain to the technical coordination and inventory management of Internet number resources. Services include: + +IPv4 address allocation and assignment +IPv6 address allocation and assignment +AS number assignment +Directory services including: +Registration transaction information (WHOIS) +Routing information (Internet routing registry) +DNS (Reverse) + +For information on requesting Internet number resources from ARIN, see https://www.arin.net/resources/index.html. This section includes the request templates, specific distribution policies, and guidelines for requesting and managing Internet number resources. + +Organization services +Organization services pertain to interaction between stakeholders, ARIN members, and ARIN. Services include: + +Elections +Members meetings +Information publication and dissemination +Education and training + +Policy development services +Policy development services facilitate the development of policy for the technical coordination and management of Internet number resources. + +All ARIN policies are set by the community. Everyone is encouraged to participate in the policy development process at public policy meetings and on the Public Policy Mailing List. The ARIN Board of Trustees ratifies policies only after: + +discussion on mailing lists and at meetings; +ARIN Advisory Council recommendation; +community consensus in favor of the policy; and +full legal and fiscal review. + +Membership is not required to participate in ARIN's policy development process or to apply for Internet number resources. + +Services include: + +Maintaining discussion e-mail lists +Conducting public policy meetings +Publishing policy documents + +Organizational structure +ARIN consists of the Internet community within its region, its members, a 7-member Board of Trustees, a 15-member Advisory Council, and a professional staff of about 50. The board of trustees and Advisory Council are elected by ARIN members for three-year terms. + +Board of trustees +The ARIN membership elects the Board of Trustees (BoT), which has ultimate responsibility for the business affairs and financial health of ARIN, and manages ARIN's operations in a manner consistent with the guidance received from the Advisory Council and the goals set by the registry's members. The BoT is responsible for determining the disposition of all revenues received to ensure all services are provided in an equitable manner. The BoT ratifies proposals generated from the membership and submitted through the Advisory Council. Executive decisions are carried out following approval by the BoT. The BoT consists of 7 members consisting of a President and CEO, a chairman, a Treasurer, and others. + +Advisory Council +In addition to the BoT, ARIN has an advisory council that advises ARIN and the BoT on IP address allocation policy and related matters. Adhering to the procedures in the Internet Resource Policy Evaluation Process, the advisory council forwards consensus-based policy proposals to the BoT for ratification. The advisory council consists of 15 elected members consisting of a Chair, Vice Chair, and others. + +History +The organization was formed in December 1997 to "provide IP registration services as an independent, nonprofit corporation." Until this time, IP address registration (outside of RIPE and APNIC regions) was done in accordance with policies set by the IETF by Network Solutions corporation as part of the InterNIC project. The National Science Foundation approved the plan for the creation of the not-for-profit organization to "give the users of IP numbers (mostly Internet service providers, corporations and other large institutions) a voice in the policies by which they are managed and allocated within the North American region."''. As part of the transition, Network Solutions corporation transitioned these tasks as well as initial staff and computer infrastructure to ARIN. + +The initial Board of Trustees consisted of Scott Bradner, John Curran, Kim Hubbard, Don Telage, Randy Bush, Raymundo Vega Aguilar, and Jon Postel (IANA) as an ex-officio member. + +The first president of ARIN was Kim Hubbard, from 1997 until 2000. Kim was succeeded by Raymond "Ray" Plzak until the end of 2008. Trustee John Curran was acting president until July 1 of 2009 when he assumed the CEO role permanently. + +Until late 2002 it served Mexico, Central America, South America and all of the Caribbean. LACNIC now handles parts of the Caribbean, Mexico, Central America, and South America. Also, Sub-Saharan Africa was part of its region until April 2005, when AfriNIC was officially recognized by ICANN as the fifth regional Internet registry. + +On 24 September 2015 ARIN has declared exhaustion of the ARIN IPv4 addresses pool. + +Service region +The countries in the ARIN service region are: + +Former service regions +ARIN formerly covered Angola, Botswana, Burundi, Republic of Congo, Democratic Republic of Congo, Eswatini, Lesotho, Malawi, Mozambique, Namibia, Rwanda, South Africa, Tanzania, Zambia, and Zimbabwe until AfriNIC was formed. + +ARIN formerly covered Argentina, Aruba, Belize, Bolivia, Brazil, Chile, Colombia, Costa Rica, Cuba, Dominican Republic, Dutch West Indies, Ecuador, El Salvador, Falkland Islands (UK), French Guiana, Guatemala, Guyana, Haiti, Honduras, Mexico, Nicaragua, Panama, Paraguay, Peru, South Georgia and the South Sandwich Islands, Suriname, Trinidad and Tobago, Uruguay, and Venezuela until LACNIC was formed. + +References + +External links +ARIN Home Page + +Regional Internet registries +Internet in Canada +Internet in the United States +Internet exchange points in North America +Organizations based in Virginia +Isaac Asimov (1920–1992) was a writer. + +Asimov may also refer to: + +People + + Stanley Asimov, Isaac Asimov's brother. + Eric Asimov, Isaac Asimov's nephew. +Places +Asimov (crater), an impact crater on Mars, named after Isaac Asimov +5020 Asimov, an asteroid named after Isaac Asimov + +Other +Asimov (surname) +Asimov's Science Fiction, an American science fiction magazine named after Isaac Asimov +Asimov's SF Adventure Magazine, a short-lived American science fiction magazine named after Isaac Asimov +Isaac Asimov Awards, four separate awards established in honor of Isaac Asimov + +See also +ASIMO +Azimov, Russian last name +is a neighborhood in the Chiyoda ward of Tokyo, Japan, generally considered to be the area surrounding Akihabara Station. Administratively, the area named Akihabara is actually found in the and Kanda-Sakumachō districts in Chiyoda. There also exists an administrative district called Akihabara in the Taitō ward further north of Akihabara Station, but it is not the place people generally refer to as Akihabara. + +The name Akihabara is a shortening of , which ultimately comes from , named after a fire-controlling deity of a firefighting shrine built after the area was destroyed by a fire in 1869. +Akihabara gained the nickname shortly after World War II for being a major shopping center for household electronic goods and the post-war black market. + +Akihabara is considered by many to be the epicentre of modern Japanese otaku culture, and is a major shopping district for video games, anime, manga, electronics and computer-related goods. Icons from popular anime and manga are displayed prominently on the shops in the area, and numerous maid cafés and some arcades are found throughout the district. + +Geography +The main area of Akihabara is located on a street just west of Akihabara Station, where most of the major shops are situated. Most of the electronics shops are just west of the station, and the anime and manga shops and the cosplay cafés are north of them. + +As mentioned above, the area called Akihabara now ranges over some districts in Chiyoda ward: , , and . There exists an administrative district called Akihabara in the Taitō ward further north of the station, but it is not the place which people generally refer to as Akihabara. It borders on Sotokanda in between Akihabara and Okachimachi stations, but is half occupied by JR tracks. + +History + +The area that is now Akihabara was once near a city gate of Edo and served as a passage between the city and northwestern Japan. This made the region a home to many craftsmen and tradesmen, as well as some low-class samurai. One of Tokyo's frequent fires destroyed the area in 1869, and the people decided to replace the buildings of the area with a shrine called Chinkasha (now known as Akiba Shrine ), meaning fire extinguisher shrine, in an attempt to prevent the spread of future fires. The locals nicknamed the shrine Akiba after the deity that could control fire, and the area around it became known as Akibagahara and later Akihabara. After Akihabara Station was built in 1888, the shrine was moved to the Taitō ward where it still resides today. + +Since its opening in 1890, Akihabara Station became a major freight transit point, which allowed a vegetable and fruit market to spring up in the district. Then, in the 1920s, the station saw a large volume of passengers after opening for public transport, and after World War II, the black market thrived in the absence of a strong government. This disconnection of Akihabara from government authority has allowed the district to grow as a market city and given rise to an excellent atmosphere for entrepreneurship. In the 1930s, this climate turned Akihabara into a future-oriented market region specializing in household electronics, such as washing machines, refrigerators, televisions, and stereos, earning Akihabara the nickname "Electric Town". + +As household electronics began to lose their futuristic appeal in the 1980s, the shops of Akihabara shifted their focus to home computers at a time when they were only used by specialists and hobbyists. This new specialization brought in a new type of consumer, computer nerds or otaku. The market in Akihabara naturally latched onto their new customer base that was focused on anime, manga, and video games. The connection between Akihabara and otaku has survived and grown to the point that the region is now known worldwide as a center for otaku culture, and some otaku even consider Akihabara to be a sacred place. + +Otaku culture + +The influence of otaku culture has shaped Akihabara's businesses and buildings to reflect the interests of otaku and gained the district worldwide fame for its distinctive imagery. Akihabara tries to create an atmosphere as close as possible to the game and anime worlds of customers' interest. The streets of Akihabara are covered with anime and manga icons, and cosplayers line the sidewalks handing out advertisements, especially for maid cafés. Release events, special events, and conventions in Akihabara give anime and manga fans frequent opportunities to meet the creators of the works they follow and strengthen the connection between the region and otaku culture. The design of many of the buildings serves to create the sort of atmosphere that draws in otaku. Architects design the stores of Akihabara to be more opaque and closed to reflect the general desire of many otaku to live in their anime worlds rather than display their interests to the world at large. + +Akihabara's role as a free market has also allowed a large amount of amateur work to find a passionate audience in the otaku who frequent the area. Doujinshi (amateur or fanmade manga based on an anime/manga/game) has been growing in Akihabara since the 1970s when publishers began to drop manga that were not ready for large markets. Comiket is largest spot sale of Doujinshi in Japan. + +See also + +Akiba-kei +Akihabara Trilogy +Kanda Shrine, Shinto shrine near Akihabara +Nipponbashi, in Osaka +Ōsu, in Nagoya +Tourism in Japan + +References + +External links + + Akihabara Area Tourism Organization + Akihabara Electrical Town Organization website + Go Tokyo Akihabara Guide + + +Chiyoda, Tokyo +Electronics districts +Neighborhoods of Tokyo +Otaku +Shopping districts and streets in Japan +Taitō +Tourist attractions in Tokyo +Akiha faith +Active Directory (AD) is a directory service developed by Microsoft for Windows domain networks. Windows Server operating systems include it as a set of processes and services. Originally, only centralized domain management used Active Directory. However, it ultimately became an umbrella title for various directory-based identity-related services. + +A domain controller is a server running the Active Directory Domain Service (AD DS) role. It authenticates and authorizes all users and computers in a Windows domain-type network, assigning and enforcing security policies for all computers and installing or updating software. For example, when a user logs into a computer part of a Windows domain, Active Directory checks the submitted username and password and determines whether the user is a system administrator or a non-admin user. Furthermore, it allows the management and storage of information, provides authentication and authorization mechanisms, and establishes a framework to deploy other related services: Certificate Services, Active Directory Federation Services, Lightweight Directory Services, and Rights Management Services. + +Active Directory uses Lightweight Directory Access Protocol (LDAP) versions 2 and 3, Microsoft's version of Kerberos, and DNS. + +Robert R. King defined it in the following way: + +History +Like many information-technology efforts, Active Directory originated out of a democratization of design using Requests for Comments (RFCs). The Internet Engineering Task Force (IETF) oversees the RFC process and has accepted numerous RFCs initiated by widespread participants. For example, LDAP underpins Active Directory. Also, X.500 directories and the Organizational Unit preceded the Active Directory concept that uses those methods. The LDAP concept began to emerge even before the founding of Microsoft in April 1975, with RFCs as early as 1971. RFCs contributing to LDAP include RFC 1823 (on the LDAP API, August 1995), RFC 2307, RFC 3062, and RFC 4533. + +Microsoft previewed Active Directory in 1999, released it first with Windows 2000 Server edition, and revised it to extend functionality and improve administration in Windows Server 2003. Active Directory support was also added to Windows 95, Windows 98, and Windows NT 4.0 via patch, with some unsupported features. Additional improvements came with subsequent versions of Windows Server. In Windows Server 2008, Microsoft added further services to Active Directory, such as Active Directory Federation Services. The part of the directory in charge of managing domains, which was a core part of the operating system, was renamed Active Directory Domain Services (ADDS) and became a server role like others. "Active Directory" became the umbrella title of a broader range of directory-based services. According to Byron Hynes, everything related to identity was brought under Active Directory's banner. + +Active Directory Services +Active Directory Services consist of multiple directory services. The best known is Active Directory Domain Services, commonly abbreviated as AD DS or simply AD. + +Domain Services +Active Directory Domain Services (AD DS) is the foundation of every Windows domain network. It stores information about domain members, including devices and users, verifies their credentials, and defines their access rights. The server running this service is called a domain controller. A domain controller is contacted when a user logs into a device, accesses another device across the network, or runs a line-of-business Metro-style app sideloaded into a machine. + +Other Active Directory services (excluding LDS, as described below) and most Microsoft server technologies rely on or use Domain Services; examples include Group Policy, Encrypting File System, BitLocker, Domain Name Services, Remote Desktop Services, Exchange Server, and SharePoint Server. + +The self-managed Active Directory DS must be distinct from managed Azure AD DS, a cloud product. + +Lightweight Directory Services +Active Directory Lightweight Directory Services (AD LDS), previously called Active Directory Application Mode (ADAM), implements the LDAP protocol for AD DS. It runs as a service on Windows Server and offers the same functionality as AD DS, including an equal API. However, AD LDS does not require the creation of domains or domain controllers. It provides a Data Store for storing directory data and a Directory Service with an LDAP Directory Service Interface. Unlike AD DS, multiple AD LDS instances can operate on the same server. + +Certificate Services +Active Directory Certificate Services (AD CS) establishes an on-premises public key infrastructure. It can create, validate, revoke and perform other similar actions, public key certificates for internal uses of an organization. These certificates can be used to encrypt files (when used with Encrypting File System), emails (per S/MIME standard), and network traffic (when used by virtual private networks, Transport Layer Security protocol or IPSec protocol). + +AD CS predates Windows Server 2008, but its name was simply Certificate Services. + +AD CS requires an AD DS infrastructure. + +Federation Services + +Active Directory Federation Services (AD FS) is a single sign-on service. With an AD FS infrastructure in place, users may use several web-based services (e.g. internet forum, blog, online shopping, webmail) or network resources using only one set of credentials stored at a central location, as opposed to having to be granted a dedicated set of credentials for each service. AD FS uses many popular open standards to pass token credentials such as SAML, OAuth or OpenID Connect. AD FS supports encryption and signing of SAML assertions. AD FS's purpose is an extension of that of AD DS: The latter enables users to authenticate with and use the devices that are part of the same network, using one set of credentials. The former enables them to use the same set of credentials in a different network. + +As the name suggests, AD FS works based on the concept of federated identity. + +AD FS requires an AD DS infrastructure, although its federation partner may not. + +Rights Management Services + +Active Directory Rights Management Services (AD RMS), previously known as Rights Management Services or RMS before Windows Server 2008, is server software that allows for information rights management, included with Windows Server. It uses encryption and selective denial to restrict access to various documents, such as corporate e-mails, Microsoft Word documents, and web pages. It also limits the operations authorized users can perform on them, such as viewing, editing, copying, saving, or printing. IT administrators can create pre-set templates for end users for convenience, but end users can still define who can access the content and what actions they can take. + +Logical structure +Active Directory is a service comprising a database and executable code. It is responsible for managing requests and maintaining the database. The Directory System Agent is the executable part, a set of Windows services and processes that run on Windows 2000 and later. Accessing the objects in Active Directory databases is possible through various interfaces such as LDAP, ADSI, messaging API, and Security Accounts Manager services. + +Objects used +Active Directory structures consist of information about objects classified into two categories: resources (such as printers) and security principals (which include user or computer accounts and groups). Each security principal is assigned a unique security identifier (SID). An object represents a single entity, such as a user, computer, printer, or group, along with its attributes. Some objects may even contain other objects within them. Each object has a unique name, and its definition is a set of characteristics and information by a schema, which determines the storage in the Active Directory. + +Administrators can extend or modify the schema using the schema object when needed. However, because each schema object is integral to the definition of Active Directory objects, deactivating or changing them can fundamentally alter or disrupt a deployment. Modifying the schema affects the entire system automatically, and new objects cannot be deleted, only deactivated. Changing the schema usually requires planning. + +Forests, trees, and domains +In an Active Directory network, the framework that holds objects has different levels: the forest, tree, and domain. Domains within a deployment contain objects stored in a single replicable database, and the DNS name structure identifies their domains, the namespace. A domain is a logical group of network objects such as computers, users, and devices that share the same Active Directory database. + +On the other hand, a tree is a collection of domains and domain trees in a contiguous namespace linked in a transitive trust hierarchy. The forest is at the top of the structure, a collection of trees with a standard global catalog, directory schema, logical structure, and directory configuration. The forest is a secure boundary that limits access to users, computers, groups, and other objects. + +Organizational units +The objects held within a domain can be grouped into organizational units (OUs). OUs can provide hierarchy to a domain, ease its administration, and can resemble the organization's structure in managerial or geographical terms. OUs can contain other OUs—domains are containers in this sense. Microsoft recommends using OUs rather than domains for structure and simplifying the implementation of policies and administration. The OU is the recommended level at which to apply group policies, which are Active Directory objects formally named group policy objects (GPOs), although policies can also be applied to domains or sites (see below). The OU is the level at which administrative powers are commonly delegated, but delegation can be performed on individual objects or attributes as well. + +Organizational units do not each have a separate namespace. As a consequence, for compatibility with Legacy NetBios implementations, user accounts with an identical sAMAccountName are not allowed within the same domain even if the accounts objects are in separate OUs. This is because sAMAccountName, a user object attribute, must be unique within the domain. However, two users in different OUs can have the same common name (CN), the name under which they are stored in the directory itself such as "fred.staff-ou.domain" and "fred.student-ou.domain", where "staff-ou" and "student-ou" are the OUs. + +In general, the reason for this lack of allowance for duplicate names through hierarchical directory placement is that Microsoft primarily relies on the principles of NetBIOS, which is a flat-namespace method of network object management that, for Microsoft software, goes all the way back to Windows NT 3.1 and MS-DOS LAN Manager. Allowing for duplication of object names in the directory, or completely removing the use of NetBIOS names, would prevent backward compatibility with legacy software and equipment. However, disallowing duplicate object names in this way is a violation of the LDAP RFCs on which Active Directory is supposedly based. + +As the number of users in a domain increases, conventions such as "first initial, middle initial, last name" (Western order) or the reverse (Eastern order) fail for common family names like Li (李), Smith or Garcia. Workarounds include adding a digit to the end of the username. Alternatives include creating a separate ID system of unique employee/student ID numbers to use as account names in place of actual users' names and allowing users to nominate their preferred word sequence within an acceptable use policy. + +Because duplicate usernames cannot exist within a domain, account name generation poses a significant challenge for large organizations that cannot be easily subdivided into separate domains, such as students in a public school system or university who must be able to use any computer across the network. + +Shadow groups + +In Microsoft's Active Directory, OUs do not confer access permissions, and objects placed within OUs are not automatically assigned access privileges based on their containing OU. It represents a design limitation specific to Active Directory, and other competing directories, such as Novell NDS, can set access privileges through object placement within an OU. + +Active Directory requires a separate step for an administrator to assign an object in an OU as a group member also within that OU. Using only the OU location to determine access permissions is unreliable since the entity might not have been assigned to the group object for that OU yet. + +A common workaround for an Active Directory administrator is to write a custom PowerShell or Visual Basic script to automatically create and maintain a user group for each OU in their Directory. The scripts run periodically to update the group to match the OU's account membership. However, they cannot instantly update the security groups anytime the directory changes, as occurs in competing directories, as security is directly implemented into the Directory. Such groups are known as shadow groups. Once created, these shadow groups are selectable in place of the OU in the administrative tools. Microsoft's Server 2008 Reference documentation mentions shadow groups but does not provide instructions on creating them. Additionally, there are no available server methods or console snap-ins for managing these groups. + +An organization must determine the structure of its information infrastructure by dividing it into one or more domains and top-level OUs. This decision is critical and can base on various models such as business units, geographical locations, IT service, object type, or a combination of these models. The immediate purpose of organizing OUs is to simplify administrative delegation and, secondarily, to apply group policies. It's important to note that while OUs serve as an administrative boundary, the forest itself is the only security boundary. All other domains must trust any administrator in the forest to maintain security. + +Partitions +The Active Directory database is organized in partitions, each holding specific object types and following a particular replication pattern. Microsoft often refers to these partitions as 'naming contexts. The 'Schema' partition defines object classes and attributes within the forest. The 'Configuration' partition contains information on the physical structure and configuration of the forest (such as the site topology). Both replicate all domains in the forest. The 'Domain' partition holds all objects created in that domain and replicates only within it. + +Physical structure +Sites are physical (rather than logical) groupings defined by one or more IP subnets. AD also defines connections, distinguishing low-speed (e.g., WAN, VPN) from high-speed (e.g., LAN) links. Site definitions are independent of the domain and OU structure and are shared across the forest. Sites play a crucial role in managing network traffic created by replication and directing clients to their nearest domain controllers (DCs). Microsoft Exchange Server 2007 uses the site topology for mail routing. Administrators can also define policies at the site level. + +The Active Directory information is physically held on one or more peer domain controllers, replacing the NT PDC/BDC model. Each DC has a copy of the Active Directory. Member servers joined to Active Directory that are not domain controllers are called Member Servers. In the domain partition, a group of objects acts as copies of domain controllers set up as global catalogs. These global catalog servers offer a comprehensive list of all objects located in the forest. + +Global Catalog servers replicate all objects from all domains to themselves, providing an international listing of entities in the forest. However, to minimize replication traffic and keep the GC's database small, only selected attributes of each object are replicated, called the partial attribute set (PAS). The PAS can be modified by modifying the schema and marking features for replication to the GC. Earlier versions of Windows used NetBIOS to communicate. Active Directory is fully integrated with DNS and requires TCP/IP—DNS. To fully operate, the DNS server must support SRV resource records, also known as service records. + +Replication +Active Directory uses multi-master replication to synchronize changes, meaning replicas pull changes from the server where the change occurred rather than being pushed to them. The Knowledge Consistency Checker (KCC) uses defined sites to manage traffic and create a replication topology of site links. Intra-site replication occurs frequently and automatically due to change notifications, which prompt peers to begin a pull replication cycle. Replication intervals between different sites are usually less consistent and don't usually use change notifications. However, it's possible to set it up to be the same as replication between locations on the same network if needed. + +Each DS3, T1, and ISDN link can have a cost, and the KCC alters the site link topology accordingly. Replication may occur transitively through several site links on same-protocol site link bridges if the price is low. However, KCC automatically costs a direct site-to-site link lower than transitive connections. A bridgehead server in each zone can send updates to other DCs in the exact location to replicate changes between sites. To configure replication for Active Directory zones, activate DNS in the domain based on the site. + +To replicate Active Directory, Remote Procedure Calls (RPC) over IP (RPC/IP) are used. SMTP is used to replicate between sites but only for modifications in the Schema, Configuration, or Partial Attribute Set (Global Catalog) GCs. It's not suitable for reproducing the default Domain partition. + +Implementation +Generally, a network utilizing Active Directory has more than one licensed Windows server computer. Backup and restore of Active Directory are possible for a network with a single domain controller. However, Microsoft recommends more than one domain controller to provide automatic failover protection of the directory. Domain controllers are ideally single-purpose for directory operations only and should not run any other software or role. + +Since certain Microsoft products, like SQL Server and Exchange, can interfere with the operation of a domain controller, isolation of these products on additional Windows servers is advised. Combining them can complicate the configuration and troubleshooting of the domain controller or the other installed software more complex. If planning to implement Active Directory, a business should purchase multiple Windows server licenses to have at least two separate domain controllers. Administrators should consider additional domain controllers for performance or redundancy and individual servers for tasks like file storage, Exchange, and SQL Server since this will guarantee that all server roles are adequately supported. + +One way to lower the physical hardware costs is by using virtualization. However, for proper failover protection, Microsoft recommends not running multiple virtualized domain controllers on the same physical hardware. + +Database +The Active-Directory database, the directory store, in Windows 2000 Server uses the JET Blue-based Extensible Storage Engine (ESE98). Each domain controller's database is limited to 16 terabytes and 2 billion objects (but only 1 billion security principals). Microsoft has created NTDS databases with more than 2 billion objects. NT4's Security Account Manager could support up to 40,000 objects. It has two main tables: the data table and the link table. Windows Server 2003 added a third main table for security descriptor single instancing. + +Programs may access the features of Active Directory via the COM interfaces provided by Active Directory Service Interfaces. + +Trusting +To allow users in one domain to access resources in another, Active Directory uses trusts. + +Trusts inside a forest are automatically created when domains are created. The forest sets the default boundaries of trust, and implicit, transitive trust is automatic for all domains within a forest. + +Terminology +One-way trust +One domain allows access to users on another domain, but the other domain does not allow access to users on the first domain. +Two-way trust +Two domains allow access to users on both domains. +Trusted domain +The domain that is trusted; whose users have access to the trusting domain. +Transitive trust +A trust that can extend beyond two domains to other trusted domains in the forest. +Intransitive trust +A one way trust that does not extend beyond two domains. +Explicit trust +A trust that an admin creates. It is not transitive and is one way only. +Cross-link trust +An explicit trust between domains in different trees or the same tree when a descendant/ancestor (child/parent) relationship does not exist between the two domains. +Shortcut +Joins two domains in different trees, transitive, one- or two-way. +Forest trust +Applies to the entire forest. Transitive, one- or two-way. +Realm +Can be transitive or nontransitive (intransitive), one- or two-way. +External +Connect to other forests or non-Active Directory domains. Nontransitive, one- or two-way. +PAM trust +A one-way trust used by Microsoft Identity Manager from a (possibly low-level) production forest to a (Windows Server 2016 functionality level) 'bastion' forest, which issues time-limited group memberships. + +Management tools +Microsoft Active Directory management tools include: +Active Directory Administrative Center (Introduced with Windows Server 2012 and above), +Active Directory Users and Computers, +Active Directory Domains and Trusts, +Active Directory Sites and Services, +ADSI Edit, +Local Users and Groups, +Active Directory Schema snap-ins for Microsoft Management Console (MMC), +SysInternals ADExplorer + +These management tools may not provide enough functionality for efficient workflow in large environments. Some third-party tools extend the administration and management capabilities. They provide essential features for a more convenient administration process, such as automation, reports, integration with other services, etc. + +Unix integration +Varying levels of interoperability with Active Directory can be achieved on most Unix-like operating systems (including Unix, Linux, Mac OS X or Java and Unix-based programs) through standards-compliant LDAP clients, but these systems usually do not interpret many attributes associated with Windows components, such as Group Policy and support for one-way trusts. + +Third parties offer Active Directory integration for Unix-like platforms, including: + PowerBroker Identity Services, formerly Likewise (BeyondTrust, formerly Likewise Software) – Allows a non-Windows client to join Active Directory + ADmitMac (Thursby Software Systems) + Samba (free software under GPLv3) – Can act as a domain controller + +The schema additions shipped with Windows Server 2003 R2 include attributes that map closely enough to RFC 2307 to be generally usable. The reference implementation of RFC 2307, nss_ldap and pam_ldap provided by PADL.com, support these attributes directly. The default schema for group membership complies with RFC 2307bis (proposed). Windows Server 2003 R2 includes a Microsoft Management Console snap-in that creates and edits the attributes. + +An alternative option is to use another directory service as non-Windows clients authenticate to this while Windows Clients authenticate to Active Directory. Non-Windows clients include 389 Directory Server (formerly Fedora Directory Server, FDS), ViewDS v7.2 XML Enabled Directory, and Sun Microsystems Sun Java System Directory Server. The latter two are both able to perform two-way synchronization with Active Directory and thus provide a "deflected" integration. + +Another option is to use OpenLDAP with its translucent overlay, which can extend entries in any remote LDAP server with additional attributes stored in a local database. Clients pointed at the local database see entries containing both the remote and local attributes, while the remote database remains completely untouched. + +Administration (querying, modifying, and monitoring) of Active Directory can be achieved via many scripting languages, including PowerShell, VBScript, JScript/JavaScript, Perl, Python, and Ruby. Free and non-free Active Directory administration tools can help to simplify and possibly automate Active Directory management tasks. + +Since October 2017 Amazon AWS offers integration with Microsoft Active Directory. + +See also + AGDLP (implementing role based access controls using nested groups) + Apple Open Directory + Flexible single master operation + + FreeIPA + List of LDAP software + System Security Services Daemon (SSSD) + Univention Corporate Server + +References + +External links + + Microsoft Technet: White paper: Active Directory Architecture (Single technical document that gives an overview about Active Directory.) + Microsoft Technet: Detailed description of Active Directory on Windows Server 2003 + Microsoft MSDN Library: [MS-ADTS]: Active Directory Technical Specification (part of the Microsoft Open Specification Promise) + Active Directory Application Mode (ADAM) + Microsoft MSDN: [AD-LDS]: Active Directory Lightweight Directory Services + Microsoft TechNet: [AD-LDS]: Active Directory Lightweight Directory Services + Microsoft MSDN: Active Directory Schema + Microsoft TechNet: Understanding Schema + Microsoft TechNet Magazine: Extending the Active Directory Schema + Microsoft MSDN: Active Directory Certificate Services + Microsoft TechNet: Active Directory Certificate Services + + +Directory services +Public key infrastructure +Microsoft server technology +Windows components +Windows 2000 +Arianism is a nontrinitarian Christological doctrine. + +Arian may also refer to: + +Pertaining to Arius + A follower of Arius, a Christian presbyter in the 3rd and 4th century +Arian controversy, several controversies which divided the early Christian church +Arian fragment, Arian palimpsest + +People + +Groups of people + Arians or Areians, ancient people living in Ariana (origin of the modern name Iran) + Aryan, a term associated with the Proto-Indo-Iranians + Aryan race, the racial concept + An inhabitant of Aria (today's Herat, Afghanistan), used by the ancient and medieval Greeks (as Ἄρ(ε)ιοι/Ar(e)ioi) and Romans (as Arii) + +Given name +Arian Asllani (born 1983), American rapper known as Action Bronson +Arian Bimo (born 1959), Albanian footballer +Arian Çuliqi, Albanian television director and screenwriter +Arian Foster (born 1986), American football player +Arian Hametaj (born 1957), Albanian footballer +Arián Iznaga, Cuban Paralympian sprinter +Arian Kabashi (born 1996), Kosovan footballer +Arian Kabashi (born 1997), Swedish footballer +Arlan Lerio (born 1976), Filipino boxer +Arian Leviste (born 1970), American electronic music artist, producer, and DJ +Arian Moayed (born 1980), Iranian-born American actor and theater producer +Arian Moreno (born 2003), Venezuelan footballer + +Surname +Arian is a surname that originated in Ancient Persia + +Arman Arian (born 1981), Iranian author, novelist and researcher +Asher Arian (1938–2010), American political scientist +Asma Arian, German-Qatari human rights activist +Laila Al-Arian (born 1980s), American broadcast journalist +Sami Al-Arian (born 1958), Palestinian-American civil rights activist +Praskovia Arian (1864–1949) Russian and Soviet writer and feminist +Bruce Arians (born 1952), American football coach and former player +Jake Arians (born 1978), American football player + +Other + Arian (band), a pop band in Iran + Arian (newspaper), an Iranian newspaper since 1914 + Arian, an outsider's name for a member of the Polish Brethren + Arian, a person born under the constellation Aries (astrology) + +See also + Arian Kartli, ancient Georgian country + Al-Arian, an Arab village in northern Israel + Aaryan, a given name and surname + Ariane (disambiguation), the French spelling of Ariadne, a character in Greek mythology + Ariann Black, Canadian-American female magician + Ariano (disambiguation) + Arien (disambiguation) + Arius (disambiguation) + Ariyan A. Johnson + Arrian, Greek historian + Aryan (name) + Ghamar Ariyan +Aldona (baptized Ona or Anna; her pagan name, Aldona, is known only from the writings of Maciej Stryjkowski; – 26 May 1339) was Queen consort of Poland (1333–1339), and a princess of the Grand Duchy of Lithuania. She was the daughter of Gediminas, Grand Duke of Lithuania. + +Biography +Aldona married Casimir III of Poland, when he was 15 or 16 years old. The bride was probably of about the same age. The marriage took place on 30 April or 16 October 1325 and was a purely political maneuver to strengthen the first Polish–Lithuanian coalition against the Teutonic Knights. Casimir was seeking allies in the dispute over Pomerania with the Order. Gediminas had just undertaken an unsuccessful attempt to Christianize Lithuania. This coalition was a prelude to the Union of Krewo in 1385, and the Union of Lublin in 1569, which resulted in the creation of a new state, the Polish–Lithuanian Commonwealth. The details of the agreement are not known; however, it is known that Gediminas released all Polish captives, some 25,000 people, who returned to Poland. The importance of the marriage was attested by the fact that Władysław abandoned his earlier plans to marry his son to Jutta of Bohemia. The alliance was put into effect when joint Polish–Lithuanian forces organized an attack against the Margraviate of Brandenburg in 1326. However, the coalition was not strong and collapsed c. 1330. Yet, there is no evidence of fighting between Poland and Lithuania while Aldona was alive. Aldona died suddenly at the end of May 1339, and was buried in Kraków. + +Aldona was remembered for her piety and devotion to music. She was accompanied by court musicians wherever she went. It was even suggested by Jan Długosz that the cymbals which were played in procession before her represented a pagan Lithuanian tradition. Her husband Casimir is known for his romantic affairs: after Aldona's death he married three more times. + +Issue +Aldona had two daughters: + Cunigunde of Poland (died in 1357); married on 1 January 1345 Louis VI the Roman, the son of Louis IV, Holy Roman Emperor. + Elisabeth (1326–1361); married Bogislaus V, Duke of Pomerania. Elisabeth's daughter, Elizabeth of Pomerania, was the fourth wife of Charles IV, Holy Roman Emperor. + +In popular culture + +Film +Queen Aldona Anna is one of the main characters in the first season of Polish historical TV drama series "Korona Królów" ("The Crown of the Kings"). She is played by Marta Bryła. + +See also + Family of Gediminas – family tree of Aldona + Gediminids + Aldona (fungus) (family Parmulariaceae), was named after her in 1900. + +References + +1309 births +1339 deaths +14th-century Polish nobility +Queens consort of Poland +Gediminids +Piast dynasty +14th-century Lithuanian people +14th-century Lithuanian women + +14th-century Polish women +Year of birth uncertain +Lithuanian princesses +Casimir III the Great +Aron Nimzowitsch (, , Aron Isayevich Nimtsovich; 7 November 1886 – 16 March 1935) was a Latvian born-Danish chess player and writer. In the late 1920s, Nimzowitsch was one of the best chess players in the world. He was the foremost figure amongst the hypermoderns and wrote a very influential book on chess theory: My System (1925–1927). Nimzowitsch's seminal work Chess Praxis, originally published in German in 1929, was purchased by a pre-teen and future World Champion Tigran Petrosian and was to have a great influence on his development as a chess player. + +Life +Born in Riga, then part of the Russian Empire, the Jewish Yiddish-speaking Nimzowitsch came from a wealthy family, where he learned chess from his father Shaya Abramovich Nimzowitsch (1860, Pinsk – 1918), who was a timber merchant. By 1897, the family lived in Dvinsk. Mother's name: Esphir Nohumovna Nimzowitsch (born Rabinovich, 1865, Polotsk – 1937), sister – Tsilya-Kreyna Pevzner, brothers Yakov, Osey and Benno. In 1904, he travelled to Berlin to study philosophy, but set aside his studies soon and began a career as a professional chess player that same year. He won his first international tournament at Munich 1906. Then, he tied for first with Alexander Alekhine at Saint Petersburg 1913/14 (the eighth All-Russian Masters' Tournament). + +During the 1917 Russian Revolution, Nimzowitsch was in the Baltic war zone. He escaped being drafted into one of the armies by feigning madness, insisting that a fly was on his head. He then escaped to Berlin, and gave his first name as Arnold, possibly to avoid anti-Semitic persecution. + +Nimzowitsch eventually moved to Copenhagen in 1922, where he lived for the rest of his life in one small rented room. In Copenhagen, he won the Nordic Championship twice, in 1924 and in 1934. He obtained Danish citizenship and lived in Denmark until his death in 1935. + +Chess career +The height of Nimzowitsch's career was the late 1920s and early 1930s. Chessmetrics places him as the third best player in the world from 1927 to 1931, behind Alexander Alekhine and José Capablanca. His most notable successes were first-place finishes at Copenhagen 1923, Marienbad 1925, Dresden 1926, Hanover 1926, the Carlsbad 1929 chess tournament, and second place behind Alekhine at the San Remo 1930 chess tournament. Nimzowitsch never developed a knack for match play, though; his best match success was a draw with Alekhine, but the match consisted of only two games and took place in 1914, thirteen years before Alekhine became world champion. + +Nimzowitsch never beat Capablanca (+0−5=6), but fared better against Alekhine (+3−9=9). He even beat Alekhine with the black pieces, in their short 1914 match at St. Petersburg. One of Nimzowitsch's most famous games is his celebrated immortal zugzwang game against Sämisch at Copenhagen 1923. Another game on this theme is his win over Paul Johner at Dresden 1926. When in form, Nimzowitsch was very dangerous with the black pieces, scoring many fine wins over top players. + +Legacy + +Nimzowitsch is considered one of the most important players and writers in chess history. His works influenced numerous other players, including Savielly Tartakower, Milan Vidmar, Richard Réti, Akiba Rubinstein, Mikhail Botvinnik, Bent Larsen, Viktor Korchnoi and Tigran Petrosian, and his influence is still felt today. + +He wrote three books on chess strategy: Mein System (My System), 1925; Die Praxis meines Systems (The Practice of My System), 1929, commonly known as Chess Praxis; and Die Blockade (The Blockade), 1925, although much in this book is generally held to be a rehash of material already presented in Mein System. Mein System is considered to be one of the most influential chess books of all time. It sets out Nimzowitsch's most important ideas, while his second most influential work, Chess Praxis, elaborates upon these ideas, adds a few new ones, and has immense value as a stimulating collection of Nimzowitsch's own games accompanied by his idiosyncratic, hyperbolic commentary which is often as entertaining as instructive. + +Nimzowitsch's chess theories, when first propounded, flew in the face of widely held orthodoxies enunciated by the dominant theorist of the era, Siegbert Tarrasch, and his disciples. Tarrasch's rigid generalizations drew on the earlier work of Wilhelm Steinitz, and were upheld by Tarrasch's sharp tongue when dismissing the opinions of doubters. While the greatest players of the time, among them Alekhine, Emanuel Lasker and Capablanca, clearly did not allow their play to be hobbled by blind adherence to general concepts that the center had to be controlled by pawns, that development had to happen in support of this control, that rooks always belong on open files, that wing openings were unsound—core ideas of Tarrasch's chess philosophy as popularly understood—beginners were taught to think of these generalizations as unalterable principles. + +Nimzowitsch supplemented many of the earlier simplistic assumptions about chess strategy by enunciating in his turn a further number of general concepts of defensive play aimed at achieving one's own goals by preventing realization of the opponent's plans. Notable in his "system" were concepts such as overprotection of pieces and pawns under attack, control of the center by pieces instead of pawns, blockading of opposing pieces (notably the passed pawns) and prophylaxis. His aforementioned game versus Paul Johner in 1926 (listed in the notable games below) is a great example of Nimzowitsch's concept of 'first restrain, then blockade and finally destroy'. He manoeuvres the black queen from its starting point to h7 to form a part of king-side blockade along with the knight on f6 and h-pawn to stop any attacking threats from White. He was also a leading exponent of the fianchetto development of bishops. Perhaps most importantly, he formulated the terminology still in use for various complex chess strategies. Others had used these ideas in practice, but he was the first to present them systematically as a lexicon of themes accompanied by extensive taxonomical observations. + +Raymond Keene writes that Nimzowitsch "was one of the world's leading grandmasters for a period extending over a quarter of a century, and for some of that time he was the obvious challenger for the world championship. ... [He was also] a great and profound chess thinker second only to Steinitz, and his works – Die Blockade, My System and Chess Praxis – established his reputation as one of the father figures of modern chess." GM Robert Byrne called him "perhaps the most brilliant theoretician and teacher in the history of the game." GM Jan Hein Donner called Nimzowitsch "a man who was too much of an artist to be able to prove he was right and who was regarded as something of a madman in his time. He would be understood only long after his death." + +Many chess openings and variations are named after Nimzowitsch, the most famous being the Nimzo-Indian Defence (1.d4 Nf6 2.c4 e6 3.Nc3 Bb4) and the less often played Nimzowitsch Defence (1.e4 Nc6). Nimzowitsch biographer GM Raymond Keene and others have referred to 1.Nf3 followed by 2.b3 as the Nimzowitsch–Larsen Attack. Keene wrote a book about the opening with that title. These openings all exemplify Nimzowitsch's ideas about controlling the center with pieces instead of pawns. He was also vital in the development of two important systems in the French Defence, the Winawer Variation (in some places called the Nimzowitsch Variation; its moves are 1.e4 e6 2.d4 d5 3.Nc3 Bb4) and the Advance Variation (1.e4 e6 2.d4 d5 3.e5). He also pioneered two provocative variations of the Sicilian Defence: the Nimzowitsch Variation, 1.e4 c5 2.Nf3 Nf6, which invites 3.e5 Nd5 (similar to Alekhine's Defence) and 1.e4 c5 2.Nf3 Nc6 3.d4 cxd4 4.Nxd4 d5?! (the latter regarded as dubious today). International Master John L. Watson has dubbed the line 1.c4 Nf6 2.Nc3 e6 3.Nf3 Bb4 the "Nimzo-English", employing this designation in Chapter 11 of his book Mastering the Chess Openings, Volume 3. + +Personality +There are many entertaining anecdotes regarding Nimzowitsch—some less savory than others. An article by Hans Kmoch and Fred Reinfeld entitled "Unconventional Surrender" on page 55 of the February 1950 Chess Review tells of the "... example of Nimzowitsch, who ... once missed first prize in a tournament in Berlin by losing to Sämisch, and when it became clear he was going to lose the game, Nimzowitsch stood up on the table and shouted, 'Gegen diesen Idioten muss ich verlieren!' ('That I should lose to this idiot!')". + +Nimzowitsch was annoyed by his opponents' smoking. A popular, but probably apocryphal, story is that once when an opponent laid an unlit cigar on the table, he complained to the tournament arbiters, "He is threatening to smoke, and as an old player you must know that the threat is stronger than the execution." + +Nimzowitsch had lengthy and somewhat bitter dogmatic conflicts with Tarrasch over whose ideas constituted 'proper' chess. + +Nimzowitsch's vanity and faith in his ideas of overprotection provoked Hans Kmoch to write a parody about him in February 1928 in the Wiener Schachzeitung. This consisted of a mock game against the fictional player "Systemsson", supposedly played and annotated by Nimzowitsch himself. The annotations gleefully exaggerate the idea of overprotection, as well as asserting the true genius of the wondrous idea. Kmoch was in fact a great admirer of Nimzowitsch, and Nimzowitsch was amused at the effort. + +Kmoch also wrote an article about his nine years with Nimzowitsch: Nimzovich suffered from the delusion that he was unappreciated and that the reason was malice. All it took to make him blossom, as I later learned, was a little praise. His paranoia was most evident when he dined in company. He always thought he was served much smaller portions than everyone else. He didn't care about the actual amount but only about the imagined affront. I once suggested that he and I order what the other actually wanted and, when the food was served, exchange plates. After we had done so, he shook his head in disbelief, still thinking that he had received the smaller portion. + +Nimzowitsch's colleague Tartakower observed of him, "He pretends to be crazy in order to drive us all crazy." + +Death +Although he had long suffered from heart trouble, his early death was unexpected; taken ill suddenly at the end of 1934, he lay bedridden for three months before dying of pneumonia. He is buried in Bispebjerg Cemetery in Copenhagen. + +Notable games + Friedrich Sämisch vs Aron Nimzowitsch, Copenhagen 1923, 0–1 The "Immortal Zugzwang Game" + Paul Johner vs Aron Nimzowitsch, Dresden 1926, 0���1 This game was chosen by Bent Larsen as his favourite game in Learn from the Grandmasters. + Richard Réti vs Aron Nimzowitsch, Berlin 1928, 0–1 + Efim Bogoljubov vs Aron Nimzowitsch, San Remo 1930, 0–1 + +See also + List of chess games + List of Jewish chess players + +References + +Further reading + +External links + +A.N.'s Alternative Spellings of Names +Nimzowitsch related articles + +1886 births +1935 deaths +Chess players from the Russian Empire +Danish chess players +Jewish chess players +Sportspeople from Riga +Latvian Jews +Danish Ashkenazi Jews +Danish people of Russian-Jewish descent +Chess theoreticians +Chess writers +Danish male writers +Deaths from cancer in Denmark +Immigrants to Denmark +Russian emigrants +Aragonese ( ; in Aragonese) is a Romance language spoken in several dialects by about 12,000 people as of 2011, in the Pyrenees valleys of Aragon, Spain, primarily in the comarcas of Somontano de Barbastro, Jacetania, Alto Gállego, Sobrarbe, and Ribagorza/Ribagorça. It is the only modern language which survived from medieval Navarro-Aragonese in a form distinct from Spanish. + +Historically, people referred to the language as ('talk' or 'speech'). Native Aragonese people usually refer to it by the names of its local dialects such as (from Valle de Hecho) or (from the Benasque Valley). + +History + +Aragonese, which developed in portions of the Ebro basin, can be traced back to the High Middle Ages. It spread throughout the Pyrenees to areas where languages similar to modern Basque might have been previously spoken. The Kingdom of Aragon (formed by the counties of Aragon, Sobrarbe and Ribagorza) expanded southward from the mountains, pushing the Moors farther south in the Reconquista and spreading the Aragonese language. + +The union of the Catalan counties and the Kingdom of Aragon which formed the 12th-century Crown of Aragon did not merge the languages of the two territories; Catalan continued to be spoken in the east and Navarro-Aragonese in the west, with the boundaries blurred by dialectal continuity. The Aragonese Reconquista in the south ended with the cession of Murcia by James I of Aragon to the Kingdom of Castile as dowry for an Aragonese princess. + +The best-known proponent of the Aragonese language was Johan Ferrandez d'Heredia, the Grand Master of the Knights Hospitaller in Rhodes at the end of the 14th century. He wrote an extensive catalog of works in Aragonese and translated several works from Greek into Aragonese (the first in medieval Europe). + +The spread of Castilian (Spanish), the Castilian origin of the Trastámara dynasty, and the similarity between Castilian (Spanish) and Aragonese facilitated the recession of the latter. A turning point was the 15th-century coronation of the Castilian Ferdinand I of Aragon, also known as Ferdinand of Antequera. + +In the early 18th century, after the defeat of the allies of Aragon in the War of the Spanish Succession, Philip V ordered the prohibition of the Aragonese language in the schools and the establishment of Castilian (Spanish) as the only official language in Aragon. This was ordered in the Aragonese Nueva Planta decrees of 1707. + +In recent times, Aragonese was mostly regarded as a group of rural dialects of Spanish. Compulsory education undermined its already weak position; for example, pupils were punished for using it. However, the 1978 Spanish transition to democracy heralded literary works and studies of the language. + +Modern Aragonese + +Aragonese is the native language of the Aragonese mountain ranges of the Pyrenees, in the comarcas of Somontano, Jacetania, Sobrarbe, and Ribagorza. Cities and towns in which Aragonese is spoken are Huesca, Graus, Monzón, Barbastro, Bielsa, Chistén, Fonz, Echo, Estadilla, Benasque, Campo, Sabiñánigo, Jaca, Plan, Ansó, Ayerbe, Broto, and El Grado. + +It is spoken as a second language by inhabitants of Zaragoza, Huesca, Ejea de los Caballeros, or Teruel. According to recent polls, there are about 25,500 speakers (2011) including speakers living outside the native area. In 2017, the Dirección General de Política Lingüística de Aragón estimated there were 10,000 to 12,000 active speakers of Aragonese. + +In 2009, the Languages Act of Aragon (Law 10/2009) recognized the "native language, original and historic" of Aragon. The language received several linguistic rights, including its use in public administration. Some of the legislation was repealed by a new law in 2013 (Law 3/2013). [See Languages Acts of Aragon for more information on the subject] + +Dialects + +Western dialect: Ansó, Valle de Hecho, Chasa, Berdún, Chaca +Central dialect: Panticosa, Biescas, Torla, Broto, Bielsa, Yebra de Basa, Aínsa-Sobrarbe +Eastern dialect: Benás, Plan, Bisagorri, Campo, Perarrúa, Graus, Estadilla +Southern dialect: Agüero, Ayerbe, Rasal, Bolea, Lierta, Uesca, Almudévar, Nozito, Labata, Alguezra, Angüés, Pertusa, Balbastro, Nabal + +Phonology + +Traits + +Aragonese has many historical traits in common with Catalan. Some are conservative features that are also shared with the Astur-Leonese languages and Galician-Portuguese, where Spanish innovated in ways that did not spread to nearby languages. + +Shared with Catalan +Romance initial f- is preserved, e.g. > ('son', Sp. , Cat. , Pt. ). +Romance groups cl-, fl- and pl- are preserved and in most dialects do not undergo any change, e.g. clavis > clau ('key', Sp. llave, Cat. clau, Pt. chave). However, in some transitional dialects from both sides (Ribagorzano in Aragonese and Ribagorçà and Pallarès in Catalan) it becomes cll-, fll- and pll-, e.g. clavis > cllau. +Romance palatal approximant (ge-, gi-, i-) consistently became medieval , as in medieval Catalan and Portuguese. This becomes modern ch , as a result of the devoicing of sibilants (see below). In Spanish, the medieval result was either /, (modern ), , or nothing, depending on the context. e.g. > ('young man', Sp. , Cat. ), > ('to freeze', Sp. , Cat. ). +Romance groups -lt-, -ct- result in , e.g. > ('done', Sp. , Cat. , Gal./Port. ), > ('many, much', Sp. , Cat. , Gal. , Port. ). +Romance groups -x-, -ps-, scj- result in voiceless palatal fricative ix , e.g. > ('crippled', Sp. , Cat. ). +Romance groups -lj-, -c'l-, -t'l- result in palatal lateral ll , e.g. > ('woman', Sp. , Cat. ), > ('needle', Sp. , Cat. ). + +Shared with Catalan and Spanish + +Open o, e from Romance result systematically in diphthongs , , e.g. > ('old woman', Sp. , Cat. , Pt. ). This includes before a palatal approximant, e.g. > ('eight', Sp. , Cat. , Pt. oito). Spanish diphthongizes except before yod, whereas Catalan only diphthongizes before yod. +Voiced stops may be lenited to approximants . + +Shared with Spanish + +Loss of final unstressed -e but not -o, e.g. > ('big'), > ('done'). Catalan loses both -e and -o (Cat. , ); Spanish preserves -o and sometimes -e (Sp. , ~ ). +Former voiced sibilants become voiceless (, ). +The palatal is most often realized as a fricative . + +Shared with neither + +Latin -b- is maintained in past imperfect endings of verbs of the second and third conjugations: ('he had', Sp. , Cat. ), ('he was sleeping', Sp. , Cat. ). +High Aragonese dialects () and some dialects of Gascon have preserved the voicelessness of many intervocalic stop consonants, e.g. > ('sheep hurdle', Cat. , Fr. ), > ('crested lark', Sp. , Cat. ). +Several Aragonese dialects maintain Latin -ll- as geminate . +The mid vowels can be as open as , mainly in the Benasque dialect. +No native word can begin with an , a trait shared with Gascon and Basque. + +Vowels + +Consonants + +Orthography + +In 2010, the Academia de l'Aragonés (founded in 2006) established an orthographic standard to modernize medieval orthography and to make it more etymological. The new orthography is used by the Aragonese Wikipedia. + +Aragonese had two orthographic standards: + The , codified in 1987 by the Consello d'a Fabla Aragonesa (CFA) at a convention in Huesca, is used by most Aragonese writers. It has a more uniform system of assigning letters to phonemes, with less regard for etymology; words traditionally written with and are uniformly written with in the Uesca system. Similarly, , , and before and are all written . It uses letters associated with Spanish, such as . + The , devised in 2004 by the Sociedat de Lingüistica Aragonesa (SLA), is used by some Aragonese writers. It uses etymological forms which are closer to Catalan, Occitan, and medieval Aragonese sources; trying to come closer to the original Aragonese and the other Occitano-Romance languages. In the SLA system , ,, , and before and are distinct, and the digraph replaces . + +During the 16th century, Aragonese Moriscos wrote aljamiado texts (Romance texts in Arabic script), possibly because of their inability to write in Arabic. The language in these texts has a mixture of Aragonese and Castilian traits, and they are among the last known written examples of the Aragonese formerly spoken in central and southern Aragon. + +In 2023, a new orthographic standard has been published by the Academia Aragonesa de la Lengua. This version is close to the Academia de l'Aragonés orthography, but with the following differences: is always spelled cu, e. g. cuan, cuestión (exception is made for some loanwords: quad, quadrívium, quark, quásar, quáter, quórum); is spelled ny or ñ by personal preference; final z is not written as tz. + +The marginal phoneme (only in loanwords, e. g. jabugo) is spelled j in the Uesca, Academia de l'Aragonés and Academia Aragonesa de la Lengua standards (not mentioned in the SLA standard). Additionally, the Academia de l'Aragonés and Academia Aragonesa de la Lengua orthographies allow the letter j in some loanwords internationally known with it (e. g. jazz, jacuzzi, which normally have in the Aragonese pronunciation) and also mention the letters k and w, also used only in loanwords (w may represent or ). + +Grammar +Aragonese grammar has a lot in common with Occitan and Catalan, but also Spanish. + +Articles + +The definite article in Aragonese has undergone dialect-related changes, with definite articles in Old Aragonese similar to their present Spanish equivalents. There are two main forms: + + +These forms are used in the eastern and some central dialects. + +These forms are used in the western and some central dialects. + +Lexicology + +Neighboring Romance languages have influenced Aragonese. Catalan and Occitan influenced Aragonese for many years. Since the 15th century, Spanish has most influenced Aragonese; it was adopted throughout Aragon as the first language, limiting Aragonese to the northern region surrounding the Pyrenees. French has also influenced Aragonese; Italian loanwords have entered through other languages (such as Catalan), and Portuguese words have entered through Spanish. Germanic words came with the conquest of the region by Germanic peoples during the fifth century, and English has introduced a number of new words into the language. + +Gender +Words that were part of the Latin second declension—as well as words that joined it later on—are usually masculine: + + > ('son') + + > ('squirrel') + +Words that were part of the Latin first declension are usually feminine: + > ('daughter'). + +Some Latin neuter plural nouns joined the first declension as singular feminine nouns: + > ('leaf'). + +Words ending in -or are feminine: + , , , and (in Medieval Aragonese) + +The names of fruit trees usually end in -era (a suffix derived from Latin -aria) and are usually feminine: + a perera, a manzanera, a nuquera, , / , a olivera, a ciresera, l'almendrera + +The genders of river names vary: + + Many ending in -a are feminine: /, , , , , , , , etc. The last was known as during the 16th century. + Many from the second and the third declension are masculine: L'Ebro, O Galligo, , . + +Pronouns +Just like most other Occitano-Romance languages, Aragonese has partitive and locative clitic pronouns derived from the Latin and : / and //; unlike Ibero-Romance. + +Such pronouns are present in most major Romance languages (Catalan and , Occitan and , French and , and Italian and /). + +/ is used for: + Partitive objects: ("I haven't seen anything like that", literally 'Not (of it) I have seen like that'). + Partitive subjects: ("It hurts so much", literally '(of it) it causes so much of pain') + Ablatives, places from which movements originate: ("Memory goes away", literally '(away from [the mind]) memory goes') + +// is used for: + Locatives, where something takes place: ("There was one of them"), literally '(Of them) there was one') + Allatives, places that movements go towards or end: ('Go there (imperative)') + +Literature + +Aragonese was not written until the 12th and 13th centuries; the history , , , and date from this period; there is also an Aragonese version of the Chronicle of the Morea, differing also in its content and written in the late 14th century called . + +Early modern period +Since 1500, Spanish has been the cultural language of Aragon; many Aragonese wrote in Spanish, and during the 17th century the Argensola brothers went to Castile to teach Spanish. +Aragonese became a popular village language. During the 17th century, popular literature in the language began to appear. In a 1650 Huesca literary contest, Aragonese poems were submitted by Matías Pradas, Isabel de Rodas and "Fileno, montañés". + +Contemporary literature + +The 19th and 20th centuries have seen a renaissance of Aragonese literature in several dialects. In 1844, Braulio Foz's novel was published in the Almudévar (southern) dialect. The 20th century featured Domingo Miral's costumbrist comedies and Veremundo Méndez Coarasa's poetry, both in Hecho (western) Aragonese; Cleto Torrodellas' poetry and Tonón de Baldomera's popular writings in the Graus (eastern) dialect and Arnal Cavero's costumbrist stories and Juana Coscujuela's novel , also in the southern dialect. + +Aragonese in modern education +The 1997 Aragonese law of languages stipulated that Aragonese (and Catalan) speakers had a right to the teaching of and in their own language. Following this, Aragonese lessons started in schools in the 1997–1998 academic year. It was originally taught as an extra-curricular, non-evaluable voluntary subject in four schools. However, whilst legally schools can choose to use Aragonese as the language of instruction, as of the 2013–2014 academic year, there are no recorded instances of this option being taken in primary or secondary education. In fact, the only current scenario in which Aragonese is used as the language of instruction is in the Aragonese philology university course, which is optional, taught over the summer and in which only some of the lectures are in Aragonese. + +Pre-school education +In pre-school education, students whose parents wish them to be taught Aragonese receive between thirty minutes to one hour of Aragonese lessons a week. In the 2014–2015 academic year there were 262 students recorded in pre-school Aragonese lessons. + +Primary school education +The subject of Aragonese now has a fully developed curriculum in primary education in Aragon. Despite this, in the 2014–2015 academic year there were only seven Aragonese teachers in the region across both pre-primary and primary education and none hold permanent positions, whilst the number of primary education students receiving Aragonese lessons was 320. + +As of 2017 there were 1068 reported Aragonese language students and 12 Aragonese language instructors in Aragon. + +Secondary school education +There is no officially approved program or teaching materials for the Aragonese language at the secondary level, and though two non-official textbooks are available ( (Benítez, 2007) and (Campos, 2014)) many instructors create their own learning materials. Further, most schools with Aragonese programs that have the possibility of being offered as an examinative subject have elected not to do so. + +As of 2007 it is possible to use Aragonese as a language of instruction for multiple courses; however, no program is yet to instruct any curricular or examinative courses in Aragonese. +As of the 2014–2015 academic year there were 14 Aragonese language students at the secondary level. + +Higher education +Aragonese is not currently a possible field of study for a bachelor's or postgraduate degree in any official capacity, nor is Aragonese used as a medium of instruction. A bachelor's or master's degree may be obtained in Magisterio (teaching) at the University of Zaragoza; however, no specialization in Aragonese language is currently available. As such those who wish to teach Aragonese at the pre-school, primary, or secondary level must already be competent in the language by being a native speaker or by other means. Further, prospective instructors must pass an ad hoc exam curated by the individual schools at which they wish to teach in order to prove their competence, as there are no recognized standard competency exams for the Aragonese language. + +Since the 1994–1995 academic year, Aragonese has been an elective subject within the bachelor's degree for primary school education at the University of Zaragoza's Huesca campus. + +The University of Zaragoza's Huesca campus also offers a Diploma de Especialización (These are studies that require a previous university degree and have a duration of between 30 and 59 ECTS credits.) in Aragonese Philology with 37 ECTS credits. + +Academia de l'Aragonés +Arredol – Electronic Aragonese newspaper +Rosario Ustáriz Borra + +References + +Further reading + +External links + +Catalogue of Aragonese publications +Academia de l'Aragonés +Consello d'a Fabla Aragonesa +Ligallo de Fablans de l'Aragonés +A.C. Nogará +Sociedat de Lingüistica Aragonesa +Aragonese language + + +Aragonese culture +Pyrenean-Mozarabic languages +Subject–verb–object languages +Advanced Mobile Phone System (AMPS) was an analog mobile phone system standard originally developed by Bell Labs and later modified in a cooperative effort between Bell Labs and Motorola. It was officially introduced in the Americas on October 13, 1983, and was deployed in many other countries too, including Israel in 1986, Australia in 1987, Singapore in 1988, and Pakistan in 1990. It was the primary analog mobile phone system in North America (and other locales) through the 1980s and into the 2000s. As of February 18, 2008, carriers in the United States were no longer required to support AMPS and companies such as AT&T and Verizon Communications have discontinued this service permanently. AMPS was discontinued in Australia in September 2000, in Pakistan by October 2004, in Israel by January 2010, and Brazil by 2010. + +History + +The first cellular network efforts began at Bell Labs and with research conducted at Motorola. +In 1960, John F. Mitchell +became Motorola's chief engineer for its mobile-communication products, and oversaw the development and marketing of the first pager to use transistors. + +Motorola had long produced mobile telephones for automobiles, but these large and heavy models consumed too much power to allow their use without the automobile's engine running. Mitchell's team, which included the gifted Dr. Martin Cooper, developed portable cellular telephony. Cooper and Mitchell were among the Motorola employees granted a patent for this work in 1973. The first call on the prototype connected, reportedly, to a wrong number. + +While Motorola was developing a cellular phone, from 1968 to 1983 Bell Labs worked out a system called Advanced Mobile Phone System (AMPS), which became the first cellular network standard in the United States. The first system was successfully deployed in Chicago, Illinois, in 1979. Motorola and others designed and built the cellular phones for this and other cellular systems. + +Martin Cooper, a former general manager for the systems division at Motorola, led a team that produced the first cellular handset in 1973 and made the first phone call from it. In 1983 Motorola introduced the DynaTAC 8000x, the first commercially available cellular phone small enough to be easily carried. He later introduced the so-called Bag Phone. + +In 1992, the first smartphone, called IBM Simon, used AMPS. Frank Canova led its design at IBM and it was demonstrated that year at the COMDEX computer-industry trade-show. A refined version of the product was marketed to consumers in 1994 by BellSouth under the name Simon Personal Communicator. The Simon was the first device that can be properly referred to as a "smartphone", even though that term was not yet coined. + +Technology +AMPS is a first-generation cellular technology that uses separate frequencies, or "channels", for each conversation. It therefore required considerable bandwidth for a large number of users. In general terms, AMPS was very similar to the older "0G" Improved Mobile Telephone Service it replaced, but used considerably more computing power to select frequencies, hand off conversations to land lines, and handle billing and call setup. + +What really separated AMPS from older systems is the "back end" call setup functionality. In AMPS, the cell centers could flexibly assign channels to handsets based on signal strength, allowing the same frequency to be re-used, without interference, if locations were separated enough. The channels were grouped so a specific set was different of the one used on the cell nearby. This allowed a larger number of phones to be supported over a geographical area. AMPS pioneers coined the term "cellular" because of its use of small hexagonal "cells" within a system. + +AMPS suffered from many weaknesses compared to today's digital technologies. As an analog standard, it was susceptible to static and noise, and there was no protection from 'eavesdropping' using a scanner or an older TV set that could tune into channels 70-83. + +Cloning + +In the 1990s, an epidemic of "cloning" cost the cellular carriers millions of dollars. An eavesdropper with specialized equipment could intercept a handset's ESN (Electronic Serial Number) and MDN or CTN (Mobile Directory Number or Cellular Telephone Number). The Electronic Serial Number, a 12-digit number sent by the handset to the cellular system for billing purposes, uniquely identified that phone on the network. The system then allowed or disallowed calls and/or features based on its customer file. A person intercepting an ESN/MDN pair could clone the combination onto a different phone and use it in other areas for making calls without paying. + +Cellular phone cloning became possible with off-the-shelf technology in the 1990s. Would-be cloners required three key items : + + A radio receiver, such as the Icom PCR-1000, that could tune into the Reverse Channel (the frequency on which AMPS phones transmit data to the tower) + A PC with a sound card and a software program called Banpaia + A phone that could easily be used for cloning, such as the Oki 900 + +The radio, when tuned to the proper frequency, would receive the signal transmitted by the cell phone to be cloned, containing the phone's ESN/MDN pair. This signal would feed into the sound-card audio-input of the PC, and Banpaia would decode the ESN/MDN pair from this signal and display it on the screen. The hacker could then copy that data into the Oki 900 phone and reboot it, after which the phone network could not distinguish the Oki from the original phone whose signal had been received. This gave the cloner, through the Oki phone, the ability to use the mobile-phone service of the legitimate subscriber whose phone was cloned – just as if that phone had been physically stolen, except that the subscriber retained his or her phone, unaware that the phone had been cloned—at least until that subscriber received his or her next bill. + +The problem became so large that some carriers required the use of a PIN before making calls. Eventually, the cellular companies initiated a system called RF Fingerprinting, whereby it could determine subtle differences in the signal of one phone from another and shut down some cloned phones. Some legitimate customers had problems with this though if they made certain changes to their own phone, such as replacing the battery and/or antenna. + +The Oki 900 could listen in to AMPS phone-calls right out-of-the-box with no hardware modifications. + +Standards +AMPS was originally standardized by American National Standards Institute (ANSI) as EIA/TIA/IS-3. EIA/TIA/IS-3 was superseded by EIA/TIA-553 and TIA interim standard with digital technologies, the cost of wireless service is so low that the problem of cloning has virtually disappeared. + +Frequency bands +AMPS cellular service operated in the 850 MHz Cellular band. For each market area, the United States Federal Communications Commission (FCC) allowed two licensees (networks) known as "A" and "B" carriers. Each carrier within a market used a specified "block" of frequencies consisting of 21 control channels and 395 voice channels. Originally, the B (wireline) side license was usually owned by the local phone company, and the A (non-wireline) license was given to wireless telephone providers. + +At the inception of cellular in 1983, the FCC had granted each carrier within a market 333 channel pairs (666 channels total). By the late 1980s, the cellular industry's subscriber base had grown into the millions across America and it became necessary to add channels for additional capacity. In 1989, the FCC granted carriers an expansion from the previous 666 channels to the final 832 (416 pairs per carrier). The additional frequencies were from the band held in reserve for future (inevitable) expansion. These frequencies were immediately adjacent to the existing cellular band. These bands had previously been allocated to UHF TV channels 70–83. + +Each duplex channel was composed of 2 frequencies. 416 of these were in the 824–849 MHz range for transmissions from mobile stations to the base stations, paired with 416 frequencies in the 869–894 MHz range for transmissions from base stations to the mobile stations. Each cell site used a different subset of these channels than its neighbors to avoid interference. This significantly reduced the number of channels available at each site in real-world systems. Each AMPS channel had a one way bandwidth of 30 kHz, for a total of 60 kHz for each duplex channel. + +Laws were passed in the US which prohibited the FCC type acceptance and sale of any receiver which could tune the frequency ranges occupied by analog AMPS cellular services. Though the service is no longer offered, these laws remain in force (although they may no longer be enforced). + +Narrowband AMPS +In 1991, Motorola proposed an AMPS enhancement known as narrowband AMPS (NAMPS or N-AMPS). + +Digital AMPS + +Later, many AMPS networks were partially converted to D-AMPS, often referred to as TDMA (though TDMA is a generic term that applies to many 2G cellular systems). D-AMPS, commercially deployed since 1993, was a digital, 2G standard used mainly by AT&T Mobility and U.S. Cellular in the United States, Rogers Wireless in Canada, Telcel in Mexico, Telecom Italia Mobile (TIM) in Brazil, VimpelCom in Russia, Movilnet in Venezuela, and Cellcom in Israel. In most areas, D-AMPS is no longer offered and has been replaced by more advanced digital wireless networks. + +Successor technologies +AMPS and D-AMPS have now been phased out in favor of either CDMA2000 or GSM, which allow for higher capacity data transfers for services such as WAP, Multimedia Messaging System (MMS), and wireless Internet access. There are some phones capable of supporting AMPS, D-AMPS and GSM all in one phone (using the GAIT standard). + +Analog AMPS being replaced by digital +In 2002, the FCC decided to no longer require A and B carriers to support AMPS service as of February 18, 2008. All AMPS carriers have converted to a digital standard such as CDMA2000 or GSM. Digital technologies such as GSM and CDMA2000 support multiple voice calls on the same channel and offer enhanced features such as two-way text messaging and data services. + +Unlike in the United States, the Canadian Radio-television and Telecommunications Commission (CRTC) and Industry Canada have not set any requirement for maintaining AMPS service in Canada. Rogers Wireless has dismantled their AMPS (along with IS-136) network; the networks were shut down May 31, 2007. Bell Mobility and Telus Mobility, who operated AMPS networks in Canada, announced that they would observe the same timetable as outlined by the FCC in the United States, and as a result would not begin to dismantle their AMPS networks until after February 2008. + +OnStar relied heavily on North American AMPS service for its subscribers because, when the system was developed, AMPS offered the most comprehensive wireless coverage in the US. In 2006, ADT asked the FCC to extend the AMPS deadline due to many of their alarm systems still using analog technology to communicate with the control centers. Cellular companies who own an A or B license (such as Verizon and Alltel) were required to provide analog service until February 18, 2008. After that point, however, most cellular companies were eager to shut down AMPS and use the remaining channels for digital services. OnStar transitioned to digital service with the help of data transport technology developed by Airbiquity, but warned customers who could not be upgraded to digital service that their service would permanently expire on January 1, 2008. + +Commercial deployments of AMPS by country + +See also +History of mobile phones + +Citations + +References +Interview of Joel Engel + +History of mobile phones +Mobile radio telephone systems +Telecommunications-related introductions in 1983 +Aerodynamics ( aero (air) + (dynamics)) is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics, and is an important domain of study in aeronautics. The term aerodynamics is often used synonymously with gas dynamics, the difference being that "gas dynamics" applies to the study of the motion of all gases, and is not limited to air. The formal study of aerodynamics began in the modern sense in the eighteenth century, although observations of fundamental concepts such as aerodynamic drag were recorded much earlier. Most of the early efforts in aerodynamics were directed toward achieving heavier-than-air flight, which was first demonstrated by Otto Lilienthal in 1891. Since then, the use of aerodynamics through mathematical analysis, empirical approximations, wind tunnel experimentation, and computer simulations has formed a rational basis for the development of heavier-than-air flight and a number of other technologies. Recent work in aerodynamics has focused on issues related to compressible flow, turbulence, and boundary layers and has become increasingly computational in nature. + +History + +Modern aerodynamics only dates back to the seventeenth century, but aerodynamic forces have been harnessed by humans for thousands of years in sailboats and windmills, and images and stories of flight appear throughout recorded history, such as the Ancient Greek legend of Icarus and Daedalus. Fundamental concepts of continuum, drag, and pressure gradients appear in the work of Aristotle and Archimedes. + +In 1726, Sir Isaac Newton became the first person to develop a theory of air resistance, making him one of the first aerodynamicists. Dutch-Swiss mathematician Daniel Bernoulli followed in 1738 with Hydrodynamica in which he described a fundamental relationship between pressure, density, and flow velocity for incompressible flow known today as Bernoulli's principle, which provides one method for calculating aerodynamic lift. In 1757, Leonhard Euler published the more general Euler equations which could be applied to both compressible and incompressible flows. The Euler equations were extended to incorporate the effects of viscosity in the first half of the 1800s, resulting in the Navier–Stokes equations. The Navier–Stokes equations are the most general governing equations of fluid flow but are difficult to solve for the flow around all but the simplest of shapes. + +In 1799, Sir George Cayley became the first person to identify the four aerodynamic forces of flight (weight, lift, drag, and thrust), as well as the relationships between them, and in doing so outlined the path toward achieving heavier-than-air flight for the next century. In 1871, Francis Herbert Wenham constructed the first wind tunnel, allowing precise measurements of aerodynamic forces. Drag theories were developed by Jean le Rond d'Alembert, Gustav Kirchhoff, and Lord Rayleigh. In 1889, Charles Renard, a French aeronautical engineer, became the first person to reasonably predict the power needed for sustained flight. Otto Lilienthal, the first person to become highly successful with glider flights, was also the first to propose thin, curved airfoils that would produce high lift and low drag. Building on these developments as well as research carried out in their own wind tunnel, the Wright brothers flew the first powered airplane on December 17, 1903. + +During the time of the first flights, Frederick W. Lanchester, Martin Kutta, and Nikolai Zhukovsky independently created theories that connected circulation of a fluid flow to lift. Kutta and Zhukovsky went on to develop a two-dimensional wing theory. Expanding upon the work of Lanchester, Ludwig Prandtl is credited with developing the mathematics behind thin-airfoil and lifting-line theories as well as work with boundary layers. + +As aircraft speed increased designers began to encounter challenges associated with air compressibility at speeds near the speed of sound. The differences in airflow under such conditions lead to problems in aircraft control, increased drag due to shock waves, and the threat of structural failure due to aeroelastic flutter. The ratio of the flow speed to the speed of sound was named the Mach number after Ernst Mach who was one of the first to investigate the properties of the supersonic flow. Macquorn Rankine and Pierre Henri Hugoniot independently developed the theory for flow properties before and after a shock wave, while Jakob Ackeret led the initial work of calculating the lift and drag of supersonic airfoils. Theodore von Kármán and Hugh Latimer Dryden introduced the term transonic to describe flow speeds between the critical Mach number and Mach 1 where drag increases rapidly. This rapid increase in drag led aerodynamicists and aviators to disagree on whether supersonic flight was achievable until the sound barrier was broken in 1947 using the Bell X-1 aircraft. + +By the time the sound barrier was broken, aerodynamicists' understanding of the subsonic and low supersonic flow had matured. The Cold War prompted the design of an ever-evolving line of high-performance aircraft. Computational fluid dynamics began as an effort to solve for flow properties around complex objects and has rapidly grown to the point where entire aircraft can be designed using computer software, with wind-tunnel tests followed by flight tests to confirm the computer predictions. Understanding of supersonic and hypersonic aerodynamics has matured since the 1960s, and the goals of aerodynamicists have shifted from the behaviour of fluid flow to the engineering of a vehicle such that it interacts predictably with the fluid flow. Designing aircraft for supersonic and hypersonic conditions, as well as the desire to improve the aerodynamic efficiency of current aircraft and propulsion systems, continues to motivate new research in aerodynamics, while work continues to be done on important problems in basic aerodynamic theory related to flow turbulence and the existence and uniqueness of analytical solutions to the Navier–Stokes equations. + +Fundamental concepts + +Understanding the motion of air around an object (often called a flow field) enables the calculation of forces and moments acting on the object. In many aerodynamics problems, the forces of interest are the fundamental forces of flight: lift, drag, thrust, and weight. Of these, lift and drag are aerodynamic forces, i.e. forces due to air flow over a solid body. Calculation of these quantities is often founded upon the assumption that the flow field behaves as a continuum. Continuum flow fields are characterized by properties such as flow velocity, pressure, density, and temperature, which may be functions of position and time. These properties may be directly or indirectly measured in aerodynamics experiments or calculated starting with the equations for conservation of mass, momentum, and energy in air flows. Density, flow velocity, and an additional property, viscosity, are used to classify flow fields. + +Flow classification +Flow velocity is used to classify flows according to speed regime. Subsonic flows are flow fields in which the air speed field is always below the local speed of sound. Transonic flows include both regions of subsonic flow and regions in which the local flow speed is greater than the local speed of sound. Supersonic flows are defined to be flows in which the flow speed is greater than the speed of sound everywhere. A fourth classification, hypersonic flow, refers to flows where the flow speed is much greater than the speed of sound. Aerodynamicists disagree on the precise definition of hypersonic flow. + +Compressible flow accounts for varying density within the flow. Subsonic flows are often idealized as incompressible, i.e. the density is assumed to be constant. Transonic and supersonic flows are compressible, and calculations that neglect the changes of density in these flow fields will yield inaccurate results. + +Viscosity is associated with the frictional forces in a flow. In some flow fields, viscous effects are very small, and approximate solutions may safely neglect viscous effects. These approximations are called inviscid flows. Flows for which viscosity is not neglected are called viscous flows. Finally, aerodynamic problems may also be classified by the flow environment. External aerodynamics is the study of flow around solid objects of various shapes (e.g. around an airplane wing), while internal aerodynamics is the study of flow through passages inside solid objects (e.g. through a jet engine). + +Continuum assumption +Unlike liquids and solids, gases are composed of discrete molecules which occupy only a small fraction of the volume filled by the gas. On a molecular level, flow fields are made up of the collisions of many individual of gas molecules between themselves and with solid surfaces. However, in most aerodynamics applications, the discrete molecular nature of gases is ignored, and the flow field is assumed to behave as a continuum. This assumption allows fluid properties such as density and flow velocity to be defined everywhere within the flow. + +The validity of the continuum assumption is dependent on the density of the gas and the application in question. For the continuum assumption to be valid, the mean free path length must be much smaller than the length scale of the application in question. For example, many aerodynamics applications deal with aircraft flying in atmospheric conditions, where the mean free path length is on the order of micrometers and where the body is orders of magnitude larger. In these cases, the length scale of the aircraft ranges from a few meters to a few tens of meters, which is much larger than the mean free path length. For such applications, the continuum assumption is reasonable. The continuum assumption is less valid for extremely low-density flows, such as those encountered by vehicles at very high altitudes (e.g. 300,000 ft/90 km) or satellites in Low Earth orbit. In those cases, statistical mechanics is a more accurate method of solving the problem than is continuum aerodynamics. The Knudsen number can be used to guide the choice between statistical mechanics and the continuous formulation of aerodynamics. + +Conservation laws +The assumption of a fluid continuum allows problems in aerodynamics to be solved using fluid dynamics conservation laws. Three conservation principles are used: + Conservation of mass Conservation of mass requires that mass is neither created nor destroyed within a flow; the mathematical formulation of this principle is known as the mass continuity equation. + Conservation of momentum The mathematical formulation of this principle can be considered an application of Newton's Second Law. Momentum within a flow is only changed by external forces, which may include both surface forces, such as viscous (frictional) forces, and body forces, such as weight. The momentum conservation principle may be expressed as either a vector equation or separated into a set of three scalar equations (x,y,z components). + Conservation of energy The energy conservation equation states that energy is neither created nor destroyed within a flow, and that any addition or subtraction of energy to a volume in the flow is caused by heat transfer, or by work into and out of the region of interest. + +Together, these equations are known as the Navier–Stokes equations, although some authors define the term to only include the momentum equation(s). The Navier–Stokes equations have no known analytical solution and are solved in modern aerodynamics using computational techniques. Because computational methods using high speed computers were not historically available and the high computational cost of solving these complex equations now that they are available, simplifications of the Navier–Stokes equations have been and continue to be employed. The Euler equations are a set of similar conservation equations which neglect viscosity and may be used in cases where the effect of viscosity is expected to be small. Further simplifications lead to Laplace's equation and potential flow theory. Additionally, Bernoulli's equation is a solution in one dimension to both the momentum and energy conservation equations. + +The ideal gas law or another such equation of state is often used in conjunction with these equations to form a determined system that allows the solution for the unknown variables. + +Branches of aerodynamics + +Aerodynamic problems are classified by the flow environment or properties of the flow, including flow speed, compressibility, and viscosity. External aerodynamics is the study of flow around solid objects of various shapes. Evaluating the lift and drag on an airplane or the shock waves that form in front of the nose of a rocket are examples of external aerodynamics. Internal aerodynamics is the study of flow through passages in solid objects. For instance, internal aerodynamics encompasses the study of the airflow through a jet engine or through an air conditioning pipe. + +Aerodynamic problems can also be classified according to whether the flow speed is below, near or above the speed of sound. A problem is called subsonic if all the speeds in the problem are less than the speed of sound, transonic if speeds both below and above the speed of sound are present (normally when the characteristic speed is approximately the speed of sound), supersonic when the characteristic flow speed is greater than the speed of sound, and hypersonic when the flow speed is much greater than the speed of sound. Aerodynamicists disagree over the precise definition of hypersonic flow; a rough definition considers flows with Mach numbers above 5 to be hypersonic. + +The influence of viscosity on the flow dictates a third classification. Some problems may encounter only very small viscous effects, in which case viscosity can be considered to be negligible. The approximations to these problems are called inviscid flows. Flows for which viscosity cannot be neglected are called viscous flows. + +Incompressible aerodynamics + +An incompressible flow is a flow in which density is constant in both time and space. Although all real fluids are compressible, a flow is often approximated as incompressible if the effect of the density changes cause only small changes to the calculated results. This is more likely to be true when the flow speeds are significantly lower than the speed of sound. Effects of compressibility are more significant at speeds close to or above the speed of sound. The Mach number is used to evaluate whether the incompressibility can be assumed, otherwise the effects of compressibility must be included. + +Subsonic flow +Subsonic (or low-speed) aerodynamics describes fluid motion in flows which are much lower than the speed of sound everywhere in the flow. There are several branches of subsonic flow but one special case arises when the flow is inviscid, incompressible and irrotational. This case is called potential flow and allows the differential equations that describe the flow to be a simplified version of the equations of fluid dynamics, thus making available to the aerodynamicist a range of quick and easy solutions. + +In solving a subsonic problem, one decision to be made by the aerodynamicist is whether to incorporate the effects of compressibility. Compressibility is a description of the amount of change of density in the flow. When the effects of compressibility on the solution are small, the assumption that density is constant may be made. The problem is then an incompressible low-speed aerodynamics problem. When the density is allowed to vary, the flow is called compressible. In air, compressibility effects are usually ignored when the Mach number in the flow does not exceed 0.3 (about 335 feet (102 m) per second or 228 miles (366 km) per hour at 60 °F (16 °C)). Above Mach 0.3, the problem flow should be described using compressible aerodynamics. + +Compressible aerodynamics + +According to the theory of aerodynamics, a flow is considered to be compressible if the density changes along a streamline. This means that – unlike incompressible flow – changes in density are considered. In general, this is the case where the Mach number in part or all of the flow exceeds 0.3. The Mach 0.3 value is rather arbitrary, but it is used because gas flows with a Mach number below that value demonstrate changes in density of less than 5%. Furthermore, that maximum 5% density change occurs at the stagnation point (the point on the object where flow speed is zero), while the density changes around the rest of the object will be significantly lower. Transonic, supersonic, and hypersonic flows are all compressible flows. + +Transonic flow + +The term Transonic refers to a range of flow velocities just below and above the local speed of sound (generally taken as Mach 0.8–1.2). It is defined as the range of speeds between the critical Mach number, when some parts of the airflow over an aircraft become supersonic, and a higher speed, typically near Mach 1.2, when all of the airflow is supersonic. Between these speeds, some of the airflow is supersonic, while some of the airflow is not supersonic. + +Supersonic flow + +Supersonic aerodynamic problems are those involving flow speeds greater than the speed of sound. Calculating the lift on the Concorde during cruise can be an example of a supersonic aerodynamic problem. + +Supersonic flow behaves very differently from subsonic flow. Fluids react to differences in pressure; pressure changes are how a fluid is "told" to respond to its environment. Therefore, since sound is, in fact, an infinitesimal pressure difference propagating through a fluid, the speed of sound in that fluid can be considered the fastest speed that "information" can travel in the flow. This difference most obviously manifests itself in the case of a fluid striking an object. In front of that object, the fluid builds up a stagnation pressure as impact with the object brings the moving fluid to rest. In fluid traveling at subsonic speed, this pressure disturbance can propagate upstream, changing the flow pattern ahead of the object and giving the impression that the fluid "knows" the object is there by seemingly adjusting its movement and is flowing around it. In a supersonic flow, however, the pressure disturbance cannot propagate upstream. Thus, when the fluid finally reaches the object it strikes it and the fluid is forced to change its properties – temperature, density, pressure, and Mach number—in an extremely violent and irreversible fashion called a shock wave. The presence of shock waves, along with the compressibility effects of high-flow velocity (see Reynolds number) fluids, is the central difference between the supersonic and subsonic aerodynamics regimes. + +Hypersonic flow + +In aerodynamics, hypersonic speeds are speeds that are highly supersonic. In the 1970s, the term generally came to refer to speeds of Mach 5 (5 times the speed of sound) and above. The hypersonic regime is a subset of the supersonic regime. Hypersonic flow is characterized by high temperature flow behind a shock wave, viscous interaction, and chemical dissociation of gas. + +Associated terminology + +The incompressible and compressible flow regimes produce many associated phenomena, such as boundary layers and turbulence. + +Boundary layers + +The concept of a boundary layer is important in many problems in aerodynamics. The viscosity and fluid friction in the air is approximated as being significant only in this thin layer. This assumption makes the description of such aerodynamics much more tractable mathematically. + +Turbulence + +In aerodynamics, turbulence is characterized by chaotic property changes in the flow. These include low momentum diffusion, high momentum convection, and rapid variation of pressure and flow velocity in space and time. Flow that is not turbulent is called laminar flow. + +Aerodynamics in other fields + +Engineering design + +Aerodynamics is a significant element of vehicle design, including road cars and trucks where the main goal is to reduce the vehicle drag coefficient, and racing cars, where in addition to reducing drag the goal is also to increase the overall level of downforce. Aerodynamics is also important in the prediction of forces and moments acting on sailing vessels. It is used in the design of mechanical components such as hard drive heads. Structural engineers resort to aerodynamics, and particularly aeroelasticity, when calculating wind loads in the design of large buildings, bridges, and wind turbines. + +The aerodynamics of internal passages is important in heating/ventilation, gas piping, and in automotive engines where detailed flow patterns strongly affect the performance of the engine. + +Environmental design +Urban aerodynamics are studied by town planners and designers seeking to improve amenity in outdoor spaces, or in creating urban microclimates to reduce the effects of urban pollution. The field of environmental aerodynamics describes ways in which atmospheric circulation and flight mechanics affect ecosystems. + +Aerodynamic equations are used in numerical weather prediction. + +Ball-control in sports +Sports in which aerodynamics are of crucial importance include soccer, table tennis, cricket, baseball, and golf, in which most players can control the trajectory of the ball using the "Magnus effect". + +See also + Aeronautics + Aerostatics + Aviation + Insect flight – how bugs fly + List of aerospace engineering topics + List of engineering topics + Nose cone design + Fluid dynamics + Computational fluid dynamics + +References + +Further reading + +General aerodynamics + + + + + +Subsonic aerodynamics + + Obert, Ed (2009). . Delft; About practical aerodynamics in industry and the effects on design of aircraft. . + +Transonic aerodynamics + + + +Supersonic aerodynamics + + + + + + + +Hypersonic aerodynamics + + + +History of aerodynamics + + + + +Aerodynamics related to engineering + +Ground vehicles + + + +Fixed-wing aircraft + + + + +Helicopters + + + + +Missiles + + +Model aircraft + + +Related branches of aerodynamics + +Aerothermodynamics + + + +Aeroelasticity + + + +Boundary layers + + + +Turbulence + +External links + + NASA Beginner's Guide to Aerodynamics + Aerodynamics for Students + Aerodynamics for Pilots + Aerodynamics and Race Car Tuning + Aerodynamic Related Projects + eFluids Bicycle Aerodynamics + Application of Aerodynamics in Formula One (F1) + Aerodynamics in Car Racing + Aerodynamics of Birds + NASA Aerodynamics Index + + +Dynamics +Energy in transport +Andreas Schlüter (1659 – c. June 1714) was a German baroque sculptor and architect, active in the Holy Roman Empire of the German Nation, the Polish–Lithuanian Commonwealth, and the Russian Tsardom. + +Biography +Andreas Schlüter was born probably in Hamburg. His early life is obscure as at least three different persons of that name are documented. The records of St. Michaelis Church, Hamburg show that an Andreas Schlüter, son of sculptor Gerhart Schlüter, had been baptized there on 22 May 1664. Documents from Danzig/Gdańsk (Royal Prussia) reported that an Andreas Schlüter (senior) had worked 1640–1652 in Danzig's Jopengasse lane (today's ulica Piwna). Possibly born in 1640, an Andres Schliter is recorded as apprentice on 9 May 1656 by the mason's guild. Other sources state 1659 as year of birth. + +He probably did spend several years abroad as Journeyman. His first work, in 1675, may have been epitaphs of the Dukes Sambor and Mestwin in the dome of Pelplin monastery. + +Schlüter's first known work was the decoration of the facade of the Danzig Royal Chapel, in 1681. He later created statues for King John III Sobieski's Wilanów Palace in Warsaw and sepulchral sculptures in Zhovkva. In 1689, he moved to Warsaw and made the pediment reliefs and sculptural work of Krasiński Palace. + +Schlüter was invited to Berlin in 1694 by Eberhard von Danckelmann to work as court sculptor at the armory (Zeughaus) for Elector Frederick III. His sculpted decorations are a masterpiece of baroque expression and pathos. While the more visible reliefs on the outside had to praise fighting, the statues of dying warriors in the interior denounced war and gave an indication of his pacifist religious beliefs (he is said to have been a Mennonite). Travelling through Italy in 1696, he studied the work of masters like Michelangelo Buonarroti and Gian Lorenzo Bernini. + +Schlüter also worked as an architect and built many state buildings in Berlin in his role as "Hofbaumeister" (Court Architect), which he lost when one tower showed signs of a weak fundament. He also served as director of the Prussian Academy of Arts from 1702 to 1704, after which he began concentrating on sculpting again, as "Hofbildhauer" (Court Sculptor). His most important equestrian sculpture is that of the "Great Elector", Frederick William of Brandenburg, cast in 1708 and placed at "Lange Brücke" near the Berlin City Palace, now situated in the honor court before Charlottenburg Palace. + +The Berlin City Palace, and many of his works, were partially destroyed by bombing in World War II and by the subsequent Communist regime. A similar fate probably befell the Amber Room, made between 1701 and 1709, Schlüter's most famous work of architecture. + +In 1713 Schlüter's fame brought him to work for Tsar Peter the Great in Saint Petersburg, where he died of an illness after creating several designs. Together with Johann Friedrich Braunstein, he designed the Grand Palace and Monplaisir Palace in Peterhof Palace Complex. Also the city's oldest building, Kikin Hall, and the reliefs at the Summer Palace are attributed to him. This way he became an important figure of Petrine Baroque. + +Extant works +Facade of the Royal Chapel, Gdańsk, 1681 +Sculptures on the facade of Wilanów Palace, Warsaw, after 1681 +Sculptures on the pediment of Krasiński Palace, Warsaw, 1682–83, 1689–1693 +Epitaph of Adam Zygmunt Konarski, St. Mary's Cathedral of the Assumption, Frombork near Gdańsk, after 1683 +Altar and crucifix in church, Węgrów near Warsaw, 1688–1690 +Altar in Czerniaków church, Warsaw, 1690 +Portrait bishop Jan Małachowski in Wawel Cathedral, Kraków 1693 +Aepulchral sculptures of the Sobieski family, Zhovkva near Lviv, 1692–93 +Equestrian statue of Elector Frederick William, courtyard of Charlottenburg Palace, Berlin, 1689–1703, with a copy in the Berlin Bode-Museum +Sculptures on the facade of the Zeughaus in Berlin, 1695–1706 +Berlin Palace, 1699–1706 +Amber Room (reconstruction) in the Catherine Palace of Tsarskoye Selo near Saint Petersburg, 1701 +Pulpit, St. Mary's Church, Berlin, 1703 +Sarcophagi of Friedrich I and Sophia Charlotte, King and Queen in Prussia in the Berlin Cathedral + +References + +External links + + + + + + Biography, by Heinz Ladendorf, 1935 + Article in Morgenpost newspaper + dhm.de: Schlüter bio at Zeughaus + English site about Kikin's Palace (Mansion House) + +1664 births +1714 deaths +German Baroque architects +Polish Baroque architects +Russian Baroque architects +17th-century German architects +18th-century German architects +German Baroque sculptors +Polish Baroque sculptors +Polish male sculptors +Ukrainian Baroque sculptors +17th-century German sculptors +18th-century German sculptors +18th-century German male artists +German male sculptors +17th-century Russian sculptors +18th-century sculptors from the Russian Empire +Russian male sculptors +Artists from Gdańsk +Architects from Hamburg +People from Royal Prussia +Ash or ashes are the solid remnants of fires. Specifically, ash refers to all non-aqueous, non-gaseous residues that remain after something burns. In analytical chemistry, to analyse the mineral and metal content of chemical samples, ash is the non-gaseous, non-liquid residue after complete combustion. + +Ashes as the end product of incomplete combustion are mostly mineral, but usually still contain an amount of combustible organic or other oxidizable residues. The best-known type of ash is wood ash, as a product of wood combustion in campfires, fireplaces, etc. The darker the wood ashes, the higher the content of remaining charcoal from incomplete combustion. The ashes are of different types. Some ashes contain natural compounds that make soil fertile. Others have chemical compounds that can be toxic but may break up in soil from chemical changes and microorganism activity. + +Like soap, ash is also a disinfecting agent (alkaline). The World Health Organization recommends ash or sand as alternative for handwashing when soap is not available. + +Natural occurrence +Ash occurs naturally from any fire that burns vegetation, and may disperse in the soil to fertilise it, or clump under it for long enough to carbonise into coal. + +Specific types + Wood ash + Products of coal combustion + Bottom ash + Fly ash + Cigarette or cigar ash + Incinerator bottom ash, a form of ash produced in incinerators + Volcanic ash, ash that consists of fragmented glass, rock, and minerals that appears during an eruption. + +Cremation ashes +Cremation ashes, also called cremated remains or "cremains," are the bodily remains left from cremation. They often take the form of a grey powder resembling coarse sand. While often referred to as ashes, the remains primarily consist of powdered bone fragments due to the cremation process, which eliminates the body's organic materials. People often store these ashes in containers like urns, although they are also sometimes buried or scattered in specific locations. + +See also + Ash (analytical chemistry) + Cinereous, consisting of ashes, ash-colored or ash-like + Potash, a term for many useful potassium salts that traditionally derived from plant ashes, but today are typically mined from underground deposits + coal, consisting of carbon as ash, and ash can be converted into coal + carbon, basic component of ashes +charcoal, carbon residue after heating wood mainly used as traditional fuel + +References + +Combustion +In calculus, an antiderivative, inverse derivative, primitive function, primitive integral or indefinite integral of a function is a differentiable function whose derivative is equal to the original function . This can be stated symbolically as . The process of solving for antiderivatives is called antidifferentiation (or indefinite integration), and its opposite operation is called differentiation, which is the process of finding a derivative. Antiderivatives are often denoted by capital Roman letters such as and . + +Antiderivatives are related to definite integrals through the second fundamental theorem of calculus: the definite integral of a function over a closed interval where the function is Riemann integrable is equal to the difference between the values of an antiderivative evaluated at the endpoints of the interval. + +In physics, antiderivatives arise in the context of rectilinear motion (e.g., in explaining the relationship between position, velocity and acceleration). The discrete equivalent of the notion of antiderivative is antidifference. + +Examples +The function is an antiderivative of , since the derivative of is . And since the derivative of a constant is zero, will have an infinite number of antiderivatives, such as , etc. Thus, all the antiderivatives of can be obtained by changing the value of in , where is an arbitrary constant known as the constant of integration. Essentially, the graphs of antiderivatives of a given function are vertical translations of each other, with each graph's vertical location depending upon the value . + +More generally, the power function has antiderivative if , and if . + +In physics, the integration of acceleration yields velocity plus a constant. The constant is the initial velocity term that would be lost upon taking the derivative of velocity, because the derivative of a constant term is zero. This same pattern applies to further integrations and derivatives of motion (position, velocity, acceleration, and so on). Thus, integration produces the relations of acceleration, velocity and displacement: + +Uses and properties +Antiderivatives can be used to compute definite integrals, using the fundamental theorem of calculus: if is an antiderivative of the integrable function over the interval , then: + +Because of this, each of the infinitely many antiderivatives of a given function may be called the "indefinite integral" of f and written using the integral symbol with no bounds: + +If is an antiderivative of , and the function is defined on some interval, then every other antiderivative of differs from by a constant: there exists a number such that for all . is called the constant of integration. If the domain of is a disjoint union of two or more (open) intervals, then a different constant of integration may be chosen for each of the intervals. For instance + +is the most general antiderivative of on its natural domain + +Every continuous function has an antiderivative, and one antiderivative is given by the definite integral of with variable upper boundary: + +for any in the domain of . Varying the lower boundary produces other antiderivatives, but not necessarily all possible antiderivatives. This is another formulation of the fundamental theorem of calculus. + +There are many functions whose antiderivatives, even though they exist, cannot be expressed in terms of elementary functions (like polynomials, exponential functions, logarithms, trigonometric functions, inverse trigonometric functions and their combinations). Examples of these are + + the error function + the Fresnel function + the sine integral + the logarithmic integral function and + sophomore's dream + +For a more detailed discussion, see also Differential Galois theory. + +Techniques of integration +Finding antiderivatives of elementary functions is often considerably harder than finding their derivatives (indeed, there is no pre-defined method for computing indefinite integrals). For some elementary functions, it is impossible to find an antiderivative in terms of other elementary functions. To learn more, see elementary functions and nonelementary integral. + +There exist many properties and techniques for finding antiderivatives. These include, among others: + + The linearity of integration (which breaks complicated integrals into simpler ones) + Integration by substitution, often combined with trigonometric identities or the natural logarithm + The inverse chain rule method (a special case of integration by substitution) + Integration by parts (to integrate products of functions) + Inverse function integration (a formula that expresses the antiderivative of the inverse of an invertible and continuous function , in terms of the antiderivative of and of ). + The method of partial fractions in integration (which allows us to integrate all rational functions—fractions of two polynomials) + The Risch algorithm + Additional techniques for multiple integrations (see for instance double integrals, polar coordinates, the Jacobian and the Stokes' theorem) + Numerical integration (a technique for approximating a definite integral when no elementary antiderivative exists, as in the case of ) + Algebraic manipulation of integrand (so that other integration techniques, such as integration by substitution, may be used) +Cauchy formula for repeated integration (to calculate the -times antiderivative of a function) + +Computer algebra systems can be used to automate some or all of the work involved in the symbolic techniques above, which is particularly useful when the algebraic manipulations involved are very complex or lengthy. Integrals which have already been derived can be looked up in a table of integrals. + +Of non-continuous functions +Non-continuous functions can have antiderivatives. While there are still open questions in this area, it is known that: + Some highly pathological functions with large sets of discontinuities may nevertheless have antiderivatives. + In some cases, the antiderivatives of such pathological functions may be found by Riemann integration, while in other cases these functions are not Riemann integrable. + +Assuming that the domains of the functions are open intervals: + + A necessary, but not sufficient, condition for a function to have an antiderivative is that have the intermediate value property. That is, if is a subinterval of the domain of and is any real number between and , then there exists a between and such that . This is a consequence of Darboux's theorem. + The set of discontinuities of must be a meagre set. This set must also be an F-sigma set (since the set of discontinuities of any function must be of this type). Moreover, for any meagre F-sigma set, one can construct some function having an antiderivative, which has the given set as its set of discontinuities. + If has an antiderivative, is bounded on closed finite subintervals of the domain and has a set of discontinuities of Lebesgue measure 0, then an antiderivative may be found by integration in the sense of Lebesgue. In fact, using more powerful integrals like the Henstock–Kurzweil integral, every function for which an antiderivative exists is integrable, and its general integral coincides with its antiderivative. + If has an antiderivative on a closed interval , then for any choice of partition if one chooses sample points as specified by the mean value theorem, then the corresponding Riemann sum telescopes to the value . However if is unbounded, or if is bounded but the set of discontinuities of has positive Lebesgue measure, a different choice of sample points may give a significantly different value for the Riemann sum, no matter how fine the partition. See Example 4 below. + +Some examples + +Basic formulae + + If , then . + +See also + Antiderivative (complex analysis) + Formal antiderivative + Jackson integral + Lists of integrals + Symbolic integration + Area + +Notes + +References + +Further reading + Introduction to Classical Real Analysis, by Karl R. Stromberg; Wadsworth, 1981 (see also) + Historical Essay On Continuity Of Derivatives by Dave L. Renfro + +External links + Wolfram Integrator — Free online symbolic integration with Mathematica + Function Calculator from WIMS + Integral at HyperPhysics + Antiderivatives and indefinite integrals at the Khan Academy + Integral calculator at Symbolab + The Antiderivative at MIT + Introduction to Integrals at SparkNotes + Antiderivatives at Harvy Mudd College + +Integral calculus +Linear operators in calculus +"The ABC Song" is the best-known song used to recite the English alphabet in alphabetical order. It is commonly used to teach the alphabet to children in English-speaking countries. "The ABC Song" was first copyrighted in 1835 by Boston music publisher Charles Bradlee. The melody is from a 1761 French music book and is also used in other nursery rhymes like "Twinkle, Twinkle, Little Star". It is not known who first set the alphabet to this tune. Songs set to the same melody are also used to teach the alphabets of other languages. + +History +The melody of "The ABC Song" was first published in the French book of music Les Amusements d’une Heure et Demy () (1761) without lyrics. It was adapted in Mozart's Twelve Variations and used in many nursery rhymes around the world, including "Ah! vous dirai-je, maman", "Twinkle, Twinkle, Little Star" and later "Baa, Baa, Black Sheep", before being used in this song. It is unknown who set the alphabet to this tune. + +"The ABC Song" was first copyrighted in 1835 by Boston music publisher Charles Bradlee under the title "The A.B.C., a German air with variations for the flute with an easy accompaniment for the piano forte." The melody was attributed to 18th-century composer Louis Le Maire. + +"The ABC Song" is commonly used in preschools across English-speaking countries. Due to the speed at which 'L, M, N, O, P' is spoken it is a common misconception among children still learning the alphabet to believe that it is in fact its own letter called "elemenopee". Some have proposed teaching slower versions of the song to avoid this issue, but attempts do so have been criticized for lacking the end rhymes and the 'L, M, N, O, P" part being an essential part of the song. The television series Sesame Street has covered the song many times, collaborating with popular artists such as Stevie Wonder, Katy Perry, Nina Simone and Usher. + +Composition and variations + +Lyrics: (each line represents two measures, or eight beats) +A, B, C, D, E, F, G... () +H, I, J, K, L, M, N, O, P... (; "L, M, N, O" spoken twice as quickly as rest of rhyme) +Q, R, S.../ T, U, V... (; pause between S and T, though in some variants, "and" is inserted) +W... X.../ Y and(/&) Z. (; pause between X and Y, and W and X last for two beats) +Now I know my ABCs. +Next time, won't you sing with me? + +Lyrics for the alternate Zed version: (each line represents two measures, or eight beats) +A, B, C, D, E, F, G... () +H, I, J, K, L, M, N... () +O, P, Q, R, S, T, U… () +V, W... X, Y and(/&) Z. (; W lasts for two beats) +Now I know my ABCs. +Next time, won't you sing with me? + +Pronunciation of "Z" +In the dialects spoken in most English-speaking countries, including the United Kingdom, the letter name for Z is pronounced /zɛd/ (Zed); although in American English, the dialect in mind by the composer, the letter is more commonly pronounced /ziː/ (Zee). In dialects which use the Zed pronunciation, the absent Zee-rhyme is generally not missed, although whilst singing the song, some children may accommodate for Zee which they would otherwise not use on a regular basis. Variants of the song exist to accommodate the Zed pronunciation. One such variation is shown below: + +a-b-c-d-e-f-g +h-i-j-k-l-m-n +o-p-q-r-s-t-u +v-w-x-y-z(ed) + +This version has no closing line and the tune is modified accordingly. There is no lengthening of the W in this version. + +Backwards alphabet +Several versions exist covering the alphabet backwards, i.e. Z to A. One version is shown below. + +z-y-x and(/&) w +v-u-t, s-r-q +p-o-n-m-l-k-j +i-h-g-f-e-d-c-b-a +Now you know your ZYXs +I bet that's not what you expected! +The e-d-c-b part is as fast as the l-m-n-o part in the normal alphabet song. + +Versions for other languages +The same melody used for "The ABC Song" has also been used for the German, French, and Arabic alphabets. A French-language version of the song is also taught in Canada, with generally no alterations to the melody except in the final line that requires adjustment to accommodate the two-syllable pronunciation of the French y. + +See also + +Traditional alphabet songs in other languages +"A Haka Mana" recites the syllabary of the Māori language to the tune of Stupid Cupid +"Alef-Bet" by Debbie Friedman, a song commonly used in American Hebrew school classrooms to teach the letters of the Hebrew alphabet +"Iroha", a recital of the Japanese syllabary +"Shiva Sutra", Sanskrit +"Thousand Character Classic", Chinese and Korean Hanja +"Ganada" (), Korean Hangul +"Zengő ABC" by Ferenc Móra, Hungarian +"Алфавит мы уже знаем", Russian +"Adalama" ( A, da, la, ma...), devised for Fulani speakers in West Africa to memorise the Adlam script. +There are several recordings of the Cherokee syllabary with this melody. +A singable version for memorising the Déné/Carrier syllabics chart. + +Notes + +References + +Songs about language +Children's songs +Early childhood education +Song +Traditional children's songs +The Antigonid dynasty (; ) was a Hellenistic dynasty of Dorian Greek provenance, descended from Alexander the Great's general Antigonus I Monophthalmus ("the One-Eyed") that ruled mainly in Macedonia. + +History + +In 309 BC, Cassander commanded Glaucias to secretly assassinate the 14-year-old Alexander IV of Macedon and his mother. The Macedonian Argead dynasty became extinct. In 306 BC, after defeating Ptolemy at the naval Battle of Salamis, Demetrius I conquered Cyprus. Following that victory Antigonus I assumed the title of Basileus (King of Alexander's Empire) and bestowed the same upon his son. Antigonus I ruled mostly over Asia Minor and northern Syria. His attempts to take control of the whole of Alexander's empire led to his defeat and death at the Battle of Ipsus in 301 BC. Antigonus's son Demetrius I Poliorcetes survived the battle, and managed to seize control of Macedon itself a few years later, but eventually lost his throne, dying as a prisoner of Seleucus I Nicator. After a period of confusion, Demetrius's son Antigonus II Gonatas was able to establish the family's control over the old Kingdom of Macedon, as well as over most of the Greek city-states, by 276 BC. + +Legacy +It was one of four dynasties established by Alexander's successors, the others being the Seleucid dynasty, Ptolemaic dynasty and Antipatrid dynasty. The last scion of the dynasty, Perseus of Macedon, who reigned between 179 and 168 BC, proved unable to stop the advancing Roman legions and Macedon's defeat at the Battle of Pydna signaled the end of the dynasty. + +Dynasty +The ruling members of the Antigonid dynasty were: + +The Greek rebel against Rome and last King of Macedonia, Andriscus, claimed to be the son of Perseus. + +Family tree of Antigonids + +Coin gallery + +See also +List of kings of Macedon + +References + +Further reading + +Adams, Winthrop Lindsay. 2010. "Alexander's Successors to 221 BC." In A Companion to Ancient Macedonia. Edited by Joseph Roisman and Ian Worthington, 208–224. Malden, MA: Wiley-Blackwell. +Anson, Edward M. 2014. Alexander's Heirs: The Age of the Successors. Malden, MA: Wiley-Blackwell. +Edson, Charles F. 1934. "The Antigonids, Heracles, and Beroia." Harvard Studies in Classical Philology 45:213–246. +O'Neil, James L. 2003. "The Ethnic Origins of the Friends of the Antigonid Kings of Macedon." The Classical Quarterly 53, no. 2: 510–22. https://www.jstor.org/stable/3556219. +The Antigonid Network. https://blogs.exeter.ac.uk/theantigonidnetwork/. Containing information about academic research, seminars, and related bibliographies and links. + + + +Ancient Macedonian dynasties +3rd century BC in Macedonia (ancient kingdom) +2nd century BC in Macedonia (ancient kingdom) +300s BC establishments +306 BC +4th-century BC establishments +2nd-century BC disestablishments +168 BC +Abingdon may refer to: + +Places + +United Kingdom +Abingdon-on-Thames, Oxfordshire + Abingdon (UK Parliament constituency) 1558–1983 + Abingdon railway station (closed) + +United States +Abingdon, Iowa +Abingdon, Illinois +Abingdon, Maryland +Abingdon, Virginia +Abingdon (plantation), Virginia + +Other countries + Abingdon Downs, Queensland, Australia +Abingdon Airport +Abingdon, Ontario, Canada +Abingdon Island, Galápagos Islands, Ecuador + +Other uses +Abingdon (1902 automobile) +Abingdon (1922 automobile) +Abingdon Arms, in Oxford, England +Abingdon Motorcycles, a former British motorcycle manufacturer +Abingdon Press, publishing house of the United Methodist Church +Abingdon Road, in Oxford, England +Abingdon School, in Abingdon-on-Thames, England +Earl of Abingdon, a title in the Peerage of England +, a U.S. Navy ship + +See also + +Abington (disambiguation) +Abjuration is the solemn repudiation, abandonment, or renunciation by or upon oath, often the renunciation of citizenship or some other right or privilege. The term comes from the Latin abjurare, "to forswear". + +Abjuration of the realm +Abjuration of the realm was a type of abjuration in ancient English law. The person taking the oath swore to leave the country directly and promptly, never to return to the kingdom unless by permission of the sovereign. This was often taken by fugitives who had taken sanctuary: + +English Commonwealth +Near the start of the English Civil War, on 18 August 1643 Parliament passed "An Ordinance for Explanation of a former Ordinance for Sequestration of Delinquents Estates with some Enlargements." The enlargements included an oath which became known as the "Oath of Abjuration": + +In 1656–7, it was reissued in what was for Catholics an even more objectionable form. Everyone was to be "adjudged a Papist" who refused this oath, and the consequent penalties began with the confiscation of two-thirds of the recusant's goods, and went on to deprive him of almost every civic right. + +The Catholic Encyclopaedia makes the point that the oath and the penalties were so severe that it stopped the efforts of the Gallicanizing party among the English Catholics, who had been ready to offer forms of submission similar to the old oath of Allegiance, which was condemned anew about this time by Pope Innocent X. + +Scotland + +During The Killing Time of the 1680s an Abjuration Oath could be put to suspects where they were given the option to abjure or renounce their allegiances. The terms of the oath were deliberately designed to offend the consciences of the Presbyterian Covenanters. Those who would not swear "whether they have arms, or not" could be "immediately killed" by field trial "before two witnesses" on a charge of high treason. John Brown was included among those executed in this judicial process by John Graham (Bluidy Clavers) on 1 May 1685. The wives and children of such men could also be put out of their houses if they had spoken to the suspect or refused the oath themselves. + +Great Britain and Ireland +In England (and after 1707 Great Britain) the Oath of Abjuration denied the royal title of James II's heirs (i.e. the direct Catholic descendant of the House of Stuart exiled after the Glorious Revolution in 1688). In England, an Oath of Abjuration was taken by Members of Parliament, clergy, and laymen, pledging to support the current British monarch and repudiated the right of the Stuarts and other claimants to the throne. This oath was imposed under William III, George I and George III. It was superseded by the oath of allegiance. In Ireland, the oath was imposed of state officeholders, teachers, lawyers, and on the clergy of the established church in from 1703, the following year it was on all Irish voters and from 1709 it could be demanded of any adult male by a magistrate. + +Bilino Polje abjuration + +The Bilino Polje abjuration, also known as "Confessio Christianorum bosniensis", was an act of alleged heresy abjuration by clergy of the Bosnian Church in presence of the Bosnian ruler, Ban Kulin, and Giovanni da Casamari. It affirmed the primacy of the pope and related to errors of practice, stemming from ignorance, rather than heretical doctrines. It was signed by seven Bosnian priors, on 8 April 1203 at Bilino Polje field, near today town of Zenica, in Bosnia and Herzegovina. The same document was brought to Buda, in 30 April by Giovanni da Casamari, Ban Kulin and two abbots, where it was examined by Emeric, King of Hungary, and the high clergy. + +The Netherlands +Another famous abjuration was brought about by the Plakkaat van Verlatinghe of July 26, 1581, the formal declaration of independence of the Low Countries from the Spanish king, Philip II. This oath was the climax of the Eighty Years' War (Dutch Revolt). + +See also + English post-Reformation oaths + Papists Act 1716 + +Notes + +External links + +Latin legal terminology +Oaths +Abitibi may refer to: + +Election districts in Canada + + Abitibi—Témiscamingue + Abitibi—Baie-James—Nunavik—Eeyou + Abitibi (provincial electoral district) + +Places in Canada + + Abitibi Canyon, Ontario, community on the Abitibi River + Abitibi Canyon Generating Station, hydroelectric power plant + Abitibi County, Quebec, historical county in southwestern Quebec + Abitibi gold belt, a gold mining region spanning the border of Ontario and Quebec + Abitibi Regional County Municipality, Quebec + Abitibi River + Abitibi-Ontario Band of Abitibi Indians, or Abitibi, former name of Wahgoshig First Nation + Abitibi-Témiscamingue, administrative region in Quebec + Lake Abitibi + +Other uses + AbitibiBowater, former name of Resolute Forest Products, a pulp and paper manufacturing company + Abitibi-Consolidated, the company that merged with Bowater to create AbitibiBowater + + Abitibi (train), former name of the Montreal–Senneterre train in Canada + + Abitibi Eskimos, former name of the Timmins Rock, an ice hockey team in Canada +A Vindication of the Rights of Woman: with Strictures on Political and Moral Subjects (1792), written by British philosopher and women's rights advocate Mary Wollstonecraft (1759–1797), is one of the earliest works of feminist philosophy. In it, Wollstonecraft responds to those educational and political theorists of the eighteenth century who did not believe women should receive a rational education. She argues that women ought to have an education commensurate with their position in society, claiming that women are essential to the nation because they educate its children and because they could be "companions" to their husbands, rather than mere wives. Instead of viewing women as ornaments to society or property to be traded in marriage, Wollstonecraft maintains that they are human beings deserving of the same fundamental rights as men. + +Wollstonecraft was prompted to write the Rights of Woman after reading Charles Maurice de Talleyrand-Périgord's 1791 report to the French National Assembly, which stated that women should only receive domestic education. From her reaction to this specific event, she launched a broad attack against double standards, indicting men for encouraging women to indulge in excessive emotion. Wollstonecraft hurried to complete the work in direct response to ongoing events; she intended to write a more thoughtful second volume but died before completing it. + +While Wollstonecraft does call for equality between the sexes in particular areas of life, especially morality, she does not explicitly state that men and women are equal. Her ambiguous statements regarding the equality of the sexes have made it difficult to classify Wollstonecraft as a modern feminist; the word itself did not emerge until decades after her death. + +Although it is commonly assumed that the Rights of Woman was unfavourably received, this is a modern misconception based on the belief that Wollstonecraft was as reviled during her lifetime as she became after the publication of William Godwin's Memoirs of the Author of A Vindication of the Rights of Woman (1798). The Rights of Woman was generally received well when it was first published in 1792. Biographer Emily W. Sunstein called it "perhaps the most original book of [Wollstonecraft's] century". Wollstonecraft's work had significant impact on advocates for women's rights in the nineteenth century, particularly the 1848 Seneca Falls Convention which produced the Declaration of Sentiments laying out the aims of the women's suffrage movement in the United States. + +Historical context + +A Vindication of the Rights of Woman was written against the tumultuous background of the French Revolution and the debates that it spawned in Britain. In a lively and sometimes vicious pamphlet war, now referred to as the Revolution controversy, British political commentators addressed topics ranging from representative government to human rights to the separation of church and state, many of these issues having been raised in France first. Wollstonecraft first entered this fray in 1790 with A Vindication of the Rights of Men, a response to Edmund Burke's Reflections on the Revolution in France (1790). In his Reflections, Burke criticized the view of many British thinkers and writers who had welcomed the early stages of the French revolution. While they saw the revolution as analogous to Britain's own Glorious Revolution in 1688, which had restricted the powers of the monarchy, Burke argued that the appropriate historical analogy was the English Civil War (1642–1651) in which CharlesI had been executed in 1649. He viewed the French revolution as the violent overthrow of a legitimate government. In Reflections he argues that citizens do not have the right to revolt against their government because civilization is the result of social and political consensus; its traditions cannot be continually challengedthe result would be anarchy. One of the key arguments of Wollstonecraft's Rights of Men, published just six weeks after Burke's Reflections, is that rights cannot be based on tradition; rights, she argues, should be conferred because they are reasonable and just, regardless of their basis in tradition. + +When Charles Maurice de Talleyrand-Périgord presented his Rapport sur l'instruction publique (1791) to the National Assembly in France, Wollstonecraft was galvanized to respond. In his recommendations for a national system of education, Talleyrand had written: +Let us bring up women, not to aspire to advantages which the Constitution denies them, but to know and appreciate those which it guarantees them... Men are destined to live on the stage of the world. A public education suits them: it early places before their eyes all the scenes of life: only the proportions are different. The paternal home is better for the education of women; they have less need to learn to deal with the interests of others, than to accustom themselves to a calm and secluded life. + +Wollstonecraft dedicated the Rights of Woman to Talleyrand: "Having read with great pleasure a pamphlet which you have lately published, I dedicate this volume to you; to induce you to reconsider the subject, and maturely weigh what I have advanced respecting the rights of woman and national education." At the end of 1791, French feminist Olympe de Gouges had published her Declaration of the Rights of Woman and of the Female Citizen, and the question of women's rights became central to political debates in both France and Britain. + +The Rights of Woman is an extension of Wollstonecraft's arguments in the Rights of Men. In the Rights of Men, as the title suggests, she is concerned with the rights of particular men (eighteenth-century British men) while in the Rights of Woman, she is concerned with the rights afforded to "woman", an abstract category. She does not isolate her argument to eighteenth-century women or British women. The first chapter of the Rights of Woman addresses the issue of natural rights and asks who has those inalienable rights and on what grounds. She answers that since natural rights are given by God, for one segment of society to deny them to another segment is a sin. The Rights of Woman thus engages not only specific events in France and in Britain but also larger questions being raised by political philosophers such as John Locke and Jean-Jacques Rousseau. + +Themes +The Rights of Woman is a long (almost 87,000 words) essay that introduces all of its major topics in the opening chapters and then repeatedly returns to them, each time from a different point of view. It also adopts a hybrid tone that combines rational argument with the fervent rhetoric of sensibility. Wollstonecraft did not employ the formal argumentation or logical prose style common to eighteenth-century philosophical writing. + +Hysteria was once seen as a physical phenomenonphysicians and anatomists believed that the more "sensitive" people's "nerves", the more emotionally affected they would be by their surroundings. Since women were thought to have keener nerves than men, it was believed that women were more emotional than men. The emotional excess associated with sensibility also theoretically produced an ethic of compassion: those with sensibility could easily sympathise with people in pain. Thus historians have credited the discourse of sensibility and those who promoted it with the increased humanitarian efforts, such as the movement to abolish the slave trade. But sensibility also paralysed those who had too much of it; as scholar G. J. Barker-Benfield explains, "an innate refinement of nerves was also identifiable with greater suffering, with weakness, and a susceptibility to disorder". + +By the time Wollstonecraft was writing the Rights of Woman, sensibility had already been under sustained attack for a number of years. Sensibility, which had initially promised to draw individuals together through sympathy, was now viewed as "profoundly separatist"; novels, plays, and poems that employed the language of sensibility asserted individual rights, sexual freedom, and unconventional familial relationships based only upon feeling. Furthermore, as Janet Todd, another scholar of sensibility, argues, "to many in Britain the cult of sensibility seemed to have feminized the nation, given women undue prominence, and emasculated men". + +Rational education +One of Wollstonecraft's central arguments in the Rights of Woman is that women should be educated in a rational manner to give them the opportunity to contribute to society. In the eighteenth century, it was often assumed by educational philosophers and conduct book writers, who wrote what one might think of as early self-help books, that women were incapable of rational or abstract thought. Women, it was believed, were too susceptible to sensibility and too fragile to be able to think clearly. Wollstonecraft, along with other female reformers such as Catharine Macaulay and Hester Chapone, maintained that women were indeed capable of rational thought and deserved to be educated. She argued this point in her own conduct book, Thoughts on the Education of Daughters (1787), in her children's book, Original Stories from Real Life (1788), as well as in the Rights of Woman. + +Stating in her preface that "my main argument is built on this simple principle, that if [woman] be not prepared by education to become the companion of man, she will stop the progress of knowledge and virtue; for truth must be common to all", Wollstonecraft contends that society will degenerate without educated women, particularly because mothers are the primary educators of young children. She attributes the problem of uneducated women to men and "a false system of education, gathered from the books written on this subject by men who [consider] females rather as women than human creatures". Women are capable of rationality; it only appears that they are not, because men have refused to educate them and encouraged them to be frivolous (Wollstonecraft describes silly women as "spaniels" and "toys"). + +Wollstonecraft attacks conduct book writers such as James Fordyce and John Gregory as well as educational philosophers such as Jean-Jacques Rousseau who argue that a woman does not need a rational education. (Rousseau argues in Emile [1762] that women should be educated for the pleasure of men; Wollstonecraft, infuriated by this argument, attacks not only it but also Rousseau himself.) Intent on illustrating the limitations that contemporary educational theory placed upon women, Wollstonecraft writes, "taught from their infancy that beauty is woman's sceptre, the mind shapes itself to the body, and, roaming round its gilt cage, only seeks to adorn its prison", implying that without this damaging ideology, which encourages young women to focus their attention on beauty and outward accomplishments, they could achieve much more. Wives could be the rational "companions" of their husbands and even pursue careers should they so choose: "women might certainly study the art of healing, and be physicians as well as nurses. And midwifery, decency seems to allot to them... they might, also, study politics... Business of various kinds, they might likewise pursue." + +For Wollstonecraft, "the most perfect education" is "an exercise of the understanding as is best calculated to strengthen the body and form the heart. Or, in other words, to enable the individual to attach such habits of virtue as will render it independent." In addition to her broad philosophical arguments, Wollstonecraft lays out a specific plan for national education to counter Talleyrand's. In Chapter 12, "On National Education", she proposes that children be sent to free day schools as well as given some education at home "to inspire a love of home and domestic pleasures". She also maintains that schooling should be co-educational, contending that men and women, whose marriages are "the cement of society", should be "educated after the same model". + +Feminism + +It is debatable to what extent the Rights of Woman is a feminist text; because the definitions of feminist vary, different scholars have come to different conclusions. The words feminist and feminism were not coined until the 1890s, and there was no feminist movement to speak of during Wollstonecraft's lifetime. Rights of Woman is often considered the source or original, "the ur-document of modern liberal feminism". In the introduction to her work on Wollstonecraft's thought, Barbara Taylor writes: +Describing [Wollstonecraft's philosophy] as feminist is problematic, and I do it only after much consideration. The label is of course anachronistic... Treating Wollstonecraft's thought as an anticipation of nineteenth and twentieth-century feminist argument has meant sacrificing or distorting some of its key elements. Leading examples of this... have been the widespread neglect of her religious beliefs, and the misrepresentation of her as a bourgeois liberal, which together have resulted in the displacement of a religiously inspired utopian radicalism by a secular, class-partisan reformism as alien to Wollstonecraft's political project as her dream of a divinely promised age of universal happiness is to our own. Even more important however has been the imposition on Wollstonecraft of a heroic-individualist brand of politics utterly at odds with her own ethically driven case for women's emancipation. Wollstonecraft's leading ambition for women was that they should attain virtue, and it was to this end that she sought their liberation. + +In the Rights of Woman, Wollstonecraft does not make the claim for gender equality using the same arguments or the same language that late nineteenth- and twentieth-century feminists later would. For instance, rather than unequivocally stating that men and women are equal, Wollstonecraft contends that men and women are equal in the eyes of God, which means that they are both subject to the same moral law. For Wollstonecraft, men and women are equal in the most important areas of life. While such an idea may not seem revolutionary to twenty-first-century readers, its implications were revolutionary during the eighteenth century. For example, it implied that both men and womennot just womenshould be modest and respect the sanctity of marriage. Wollstonecraft's argument exposed the sexual double standard of the late eighteenth century and demanded that men adhere to the same virtues demanded of women. + +However, Wollstonecraft's arguments for equality stand in contrast to her statements respecting the superiority of masculine strength and valour. Wollstonecraft states: +Let it not be concluded, that I wish to invert the order of things; I have already granted, that, from the constitution of their bodies, men seem to be designed by Providence to attain a greater degree of virtue. I speak collectively of the whole sex; but I see not the shadow of a reason to conclude that their virtues should differ in respect to their nature. In fact, how can they, if virtue has only one eternal standard? I must therefore, if I reason consequentially, as strenuously maintain that they have the same simple direction, as that there is a God. + +Wollstonecraft calls on men, rather than women, to initiate the social and political changes she outlines in the Rights of Woman. Because women are uneducated, they cannot alter their own situationmen must come to their aid. Wollstonecraft writes at the end of her chapter "Of the Pernicious Effects Which Arise from the Unnatural Distinctions Established in Society": +I then would fain convince reasonable men of the importance of some of my remarks; and prevail on them to weigh dispassionately the whole tenor of my observations... I appeal to their understandings; and, as a fellow-creature, claim, in the name of my sex, some interest in their hearts. I entreat them to assist to emancipate their companion, to make her a help meet for them! Would men but generously snap our chains, and be content with rational fellowship instead of slavish obedience, they would find us more observant daughters, more affectionate sisters, more faithful wives, more reasonable mothersin a word, better citizens. + +Wollstonecraft's last novel, Maria: or, The Wrongs of Woman (1798), the fictionalized sequel to the Rights of Woman, is usually considered her most radical feminist work. + +Sensibility +One of Wollstonecraft's most scathing criticisms in the Rights of Woman is against false and excessive sensibility, particularly in women. She argues that women who succumb to sensibility are "blown about by every momentary gust of feeling"; because these women are "the prey of their senses", they cannot think rationally. Not only do they do harm to themselves but they also do harm to all of civilization: these are not women who can refine civilizationthese are women who will destroy it. But reason and feeling are not independent for Wollstonecraft; rather, she believes that they should inform each other. For Wollstonecraft the passions underpin all reason. This was a theme that she would return to throughout her career, but particularly in her novels Mary: A Fiction (1788) and Maria: or, The Wrongs of Woman. For the eighteenth-century Scottish philosopher David Hume, reason is dominated by the passions. He held that passions rather than reason govern human behaviour, famously proclaiming in A Treatise of Human Nature that "Reason is, and ought only to be the slave of the passions". + +As part of her argument that women should not be overly influenced by their feelings and emotions, Wollstonecraft emphasises that they should not be constrained by or made slaves to their bodies or their sexual feelings. This particular argument has led many modern feminists to suggest that Wollstonecraft intentionally avoids granting women any sexual desire. Cora Kaplan argues that the "negative and prescriptive assault on female sexuality" is a leitmotif of the Rights of Woman. For example, Wollstonecraft advises her readers to "calmly let passion subside into friendship" in the ideal companionate marriage (that is, in the ideal of a love-based marriage that was developing at the time). It would be better, she writes, when "two virtuous young people marry . . . if some circumstances checked their passion". According to Wollstonecraft, "love and friendship cannot subsist in the same bosom". As Mary Poovey explains, "Wollstonecraft betrays her fear that female desire might in fact court man's lascivious and degrading attentions, that the subordinate position women have been given might even be deserved. Until women can transcend their fleshly desires and fleshly forms, they will be hostage to the body." If women are not interested in sexuality, they cannot be dominated by men. Wollstonecraft worries that women are consumed with "romantic wavering", that is, they are interested only in satisfying their lusts. Because the Rights of Woman eliminates sexuality from a woman's life, Kaplan contends, it "expresses a violent antagonism to the sexual" while at the same time "exaggerat[ing] the importance of the sensual in the everyday life of women". Wollstonecraft was so determined to wipe sexuality from her picture of the ideal woman that she ended up foregrounding it by insisting upon its absence. But as Kaplan and others have remarked, Wollstonecraft may have been forced to make this sacrifice: "it is important to remember that the notion of woman as politically enabled and independent [was] fatally linked [during the eighteenth century] to the unrestrained and vicious exercise of her sexuality." + +Republicanism + +Claudia Johnson, a prominent Wollstonecraft scholar, has called the Rights of Woman "a republican manifesto". Johnson contends that Wollstonecraft is hearkening back to the Commonwealth tradition of the seventeenth century and attempting to reestablish a republican ethos. In Wollstonecraft's version, there would be strong, but separate, masculine and feminine roles for citizens. According to Johnson, Wollstonecraft "denounces the collapse of proper sexual distinction as the leading feature of her age, and as the grievous consequence of sentimentality itself. The problem undermining society in her view is feminized men". If men feel free to adopt both the masculine position and the sentimental feminine position, she argues, women have no position open to them in society. Johnson therefore sees Wollstonecraft as a critic, in both the Rights of Men and the Rights of Woman, of the "masculinization of sensitivity" in such works as Edmund Burke's Reflections on the Revolution in France. + +In the Rights of Woman Wollstonecraft adheres to a version of republicanism that includes a belief in the eventual overthrow of all titles, including the monarchy. She also suggests that all men and women should be represented in government. But the bulk of her "political criticism", as Chris Jones, a Wollstonecraft scholar, explains, "is couched predominantly in terms of morality". Her definition of virtue focuses on the individual's happiness rather than, for example, the good of society. This is reflected in her explanation of natural rights. Because rights ultimately proceed from God, Wollstonecraft maintains that there are duties, tied to those rights, incumbent upon each and every person. For Wollstonecraft, the individual is taught republicanism and benevolence within the family; domestic relations and familial ties are crucial to her understanding of social cohesion and patriotism. + +Class +In many ways the Rights of Woman is inflected by a bourgeois view of the world, as is its direct predecessor the Rights of Men. Wollstonecraft addresses her text to the middle class, which she calls the "most natural state". She also frequently praises modesty and industry, virtues which, at the time, were associated with the middle class. From her position as a middle-class writer arguing for a middle-class ethos, Wollstonecraft also attacks the wealthy, criticizing them using the same arguments she employs against women. She points out the "false-refinement, immorality, and vanity" of the rich, calling them "weak, artificial beings, raised above the common wants and affections of their race, in a premature unnatural manner [who] undermine the very foundation of virtue, and spread corruption through the whole mass of society". + +But Wollstonecraft's criticisms of the wealthy do not necessarily reflect a concomitant sympathy for the poor. For her, the poor are fortunate because they will never be trapped by the snares of wealth: "Happy is it when people have the cares of life to struggle with; for these struggles prevent their becoming a prey to enervating vices, merely from idleness!" She contends that charity has only negative consequences because, as Jones puts it, she "sees it as sustaining an unequal society while giving the appearance of virtue to the rich". + +In her national plan for education, she retains class distinctions (with an exception for the intelligent), suggesting that: "After the age of nine, girls and boys, intended for domestic employments, or mechanical trades, ought to be removed to other schools, and receive instruction, in some measure appropriated to the destination of each individual... The young people of superior abilities, or fortune, might now be taught, in another school, the dead and living languages, the elements of science, and continue the study of history and politics, on a more extensive scale, which would not exclude polite literature." + +Rhetoric and style + +In attempting to navigate the cultural expectations of female writers and the generic conventions of political and philosophical discourse, Wollstonecraft, as she does throughout her oeuvre, constructs a unique blend of masculine and feminine styles in the Rights of Woman. She uses the language of philosophy, referring to her work as a "treatise" with "arguments" and "principles". However, Wollstonecraft also uses a personal tone, employing "I" and "you", dashes and exclamation marks, and autobiographical references to create a distinctly feminine voice in the text. The Rights of Woman further hybridizes its genre by weaving together elements of the conduct book, the short essay, and the novel, genres often associated with women, while at the same time claiming that these genres could be used to discuss philosophical topics such as rights. + +Although Wollstonecraft argues against excessive sensibility, the rhetoric of the Rights of Woman is at times heated and attempts to provoke the reader. Many of the most emotional comments in the book are directed at Rousseau. For example, after excerpting a long passage from Emile (1762), Wollstonecraft pithily states, "I shall make no other comments on this ingenious passage, than just to observe, that it is the philosophy of lasciviousness." A mere page later, after indicting Rousseau's plan for female education, she writes "I must relieve myself by drawing another picture." These terse exclamations are meant to draw the reader to her side of the argument (it is assumed that the reader will agree with them). While she claims to write in a plain style so that her ideas will reach the broadest possible audience, she actually combines the plain, rational language of the political treatise with the poetic, passionate language of sensibility to demonstrate that one can combine rationality and sensibility in the same self. + +In her efforts to vividly describe the condition of women within society, Wollstonecraft employs several different analogies. She often compares women to slaves, arguing that their ignorance and powerlessness places them in that position. But at the same time, she also compares them to "capricious tyrants" who use cunning and deceit to manipulate the men around them. At one point, she reasons that a woman can become either a slave or tyrant, which she describes as two sides of the same coin. Wollstonecraft also compares women to soldiers; like military men, they are valued only for their appearance and obedience. And like the rich, women's "softness" has "debased mankind". + +Revision +Wollstonecraft was forced to write the Rights of Woman hurriedly to respond to Talleyrand and ongoing events. Upon completing the work, she wrote to her friend William Roscoe: "I am dissatisfied with myself for not having done justice to the subject... Do not suspect me of false modestyI mean to say that had I allowed myself more time I could have written a better book, in every sense of the word... I intend to finish the next volume before I begin to print, for it is not pleasant to have the Devil coming for the conclusion of a sheet fore it is written." When Wollstonecraft revised the Rights of Woman for the second edition, she took the opportunity not only to fix small spelling and grammar mistakes but also to bolster the feminist claims of her argument. She changed some of her statements regarding female and male difference to reflect a greater equality between the sexes. + +Wollstonecraft never wrote the second part to the Rights of Woman, although William Godwin published her "Hints", which were "chiefly designed to have been incorporated in the second part of the Vindication of the Rights of Woman", in the posthumous collection of her works. However, she did begin writing the novel Maria: or, The Wrongs of Woman, which most scholars consider a fictionalized sequel to the Rights of Woman. It was unfinished at her death and also included in the Posthumous Works published by Godwin. + +Reception and legacy + +When it was first published in 1792, the Rights of Woman was reviewed favourably by the Analytical Review, the General Magazine, the Literary Magazine, New York Magazine, and the Monthly Review, although the assumption persists that Rights of Woman received hostile reviews. It was almost immediately released in a second edition in 1792, several American editions appeared, and it was translated into French. Taylor writes that "it was an immediate success". Moreover, other writers such as Mary Hays and Mary Robinson specifically alluded to Wollstonecraft's text in their own works. Hays cited the Rights of Woman in her novel Memoirs of Emma Courtney (1796) and modelled her female characters after Wollstonecraft's ideal woman. + +Although female conservatives such as Hannah More excoriated Wollstonecraft personally, they actually shared many of the same values. As the scholar Anne Mellor has shown, both More and Wollstonecraft wanted a society founded on "Christian virtues of rational benevolence, honesty, personal virtue, the fulfillment of social duty, thrift, sobriety, and hard work". During the early 1790s, many writers within British society were engaged in an intense debate regarding the position of women in society. For example, the respected poet and essayist Anna Laetitia Barbauld and Wollstonecraft sparred back and forth; Barbauld published several poems responding to Wollstonecraft's work and Wollstonecraft commented on them in footnotes to the Rights of Woman. The work also provoked outright hostility. The bluestocking Elizabeth Carter was unimpressed with the work. Thomas Taylor, the Neoplatonist translator who had been a landlord to the Wollstonecraft family in the late 1770s, swiftly wrote a satire called A Vindication of the Rights of Brutes: if women have rights, why not animals too? + +After Wollstonecraft died in 1797, her husband William Godwin published his Memoirs of the Author of A Vindication of the Rights of Woman (1798). He revealed much about her private life that had previously not been known to the public: her illegitimate child, her love affairs, and her attempts at suicide. While Godwin believed he was portraying his wife with love, sincerity, and compassion, contemporary readers were shocked by Wollstonecraft's unorthodox lifestyle and she became a reviled figure. Richard Polwhele targeted her in particular in his anonymous long poem The Unsex'd Females (1798), a defensive reaction to women's literary self-assertion: Hannah More is Christ to Wollstonecraft's Satan. His poem was "well known" among the responses to A Vindication. + +Wollstonecraft's ideas became associated with her life story and women writers felt that it was dangerous to mention her in their texts. Hays, who had previously been a close friend and an outspoken advocate for Wollstonecraft and her Rights of Woman, for example, did not include her in the collection of Illustrious and Celebrated Women she published in 1803. Maria Edgeworth specifically distances herself from Wollstonecraft in her novel Belinda (1802); she caricatures Wollstonecraft as a radical feminist in the character of Harriet Freke. But, like Jane Austen, she does not reject Wollstonecraft's ideas. Both Edgeworth and Austen argue that women are crucial to the development of the nation; moreover, they portray women as rational beings who should choose companionate marriage. + +The negative views towards Wollstonecraft persisted for over a century. The Rights of Woman was not reprinted until the middle of the nineteenth century and it still retained an aura of ill-repute. George Eliot wrote "there is in some quarters a vague prejudice against the Rights of Woman as in some way or other a reprehensible book, but readers who go to it with this impression will be surprised to find it eminently serious, severely moral, and withal rather heavy". The suffragist (i.e. moderate reformer, as opposed to suffragette) Millicent Garrett Fawcett wrote the introduction to the centenary edition of the Rights of Woman, cleansing the memory of Wollstonecraft and claiming her as the foremother of the struggle for the vote. While the Rights of Woman may have paved the way for feminist arguments, twentieth-century feminists have tended to use Wollstonecraft's life story, rather than her texts, for inspiration; her unorthodox lifestyle convinced them to try new "experiments in living", as Virginia Woolf termed it in her famous essay on Wollstonecraft. However, there is some evidence that the Rights of Woman may be influencing current feminists. Ayaan Hirsi Ali, a feminist who is critical of Islam's dictates regarding women, cites the Rights of Woman in her autobiography Infidel, writing that she was "inspired by Mary Wollstonecraft, the pioneering feminist thinker who told women they had the same ability to reason as men did and deserved the same rights". Miriam Schneir also includes this text in her anthology Feminism: The Essential Historical Writings, labelling it as one of the essential feminist works. Further evidence of the enduring legacy of Wollstonecraft's A Vindication may be seen by direct references in recent historical fiction set: for example, in The Silk Weaver (1998) set in the late eighteenth century among Dublin silk weavers, author Gabrielle Warnock (1998) intervenes as narrator to hold up ‘Rights of Woman’ for the reader to reflect upon the politics, morals, and feelings of her female characters. In Death Comes to Pemberley (2011), set in 1803, P. D. James has one male character reference Rights of Woman in reproving another (Darcy) for denying voice to the woman in matters that concern her. + +See also +"On the Equality of the Sexes" +Timeline of Mary Wollstonecraft + +Notes + +Bibliography + +Modern reprints +Wollstonecraft, Mary. The Complete Works of Mary Wollstonecraft. Ed. Janet Todd and Marilyn Butler. 7 vols. London: William Pickering, 1989. . +Wollstonecraft, Mary. The Vindications: The Rights of Men and The Rights of Woman. Eds. D.L. Macdonald and Kathleen Scherf. Toronto: Broadview Literary Texts, 1997. +Wollstonecraft, Mary. A Vindication of the Rights of Woman. Ed. Miriam Brody Kramnick. Rev. ed. Harmondsworth: Penguin, 2004. . +Wollstonecraft, Mary. A Vindication of the Rights of Woman. Ed. Deidre Shauna Lynch. 3rd ed. New York: W. W. Norton and Company, 2009. . +Wollstonecraft, Mary. A Vindication of the Rights of Men and A Vindication of the Rights of Woman. Ed. Sylvana Tomaselli. Cambridge: Cambridge University Press, 1995. . + +Contemporary reviews + +Analytical Review 12 (1792): 241–249; 13 (1792): 418–489. +Christian Miscellany 1 (1792): 209–212. +Critical Review New Series 4 (1792): 389–398; 5 (1792): 132–141. +General Magazine and Imperial Review 6.2 (1792): 187–191. +Literary Magazine and British Review 8 (1792); 133–139. +Monthly Review New Series 8 (1792): 198–209. +New Annual Register 13 (1792): 298. +New-York Magazine 4 (1793): 77–81. +Scots Magazine 54 (1792): 284–290. +Sentimental and Masonic Magazine 1 (1792): 63–72. +Town and Country Magazine 24 (1792): 279. + +Secondary sources +Barker-Benfield, G.J. The Culture of Sensibility: Sex and Society in Eighteenth-Century Britain. Chicago: University of Chicago Press, 1992. . +DeLucia, JoEllen. "A Vindication of the Rights of Woman". The Literary Encyclopedia, Volume 1.2.1.06: English Writing and Culture of the Romantic Period, 1789–1837, 2011. +Gordon, Lyndall. Vindication: A Life of Mary Wollstonecraft. Great Britain: Virago, 2005. . +Hume, David. A Treatise of Human Nature 1. London: John Noon, 1739. Retrieved 19 May 2020. +Janes, R.M. "On the Reception of Mary Wollstonecraft's A Vindication of the Rights of Woman". Journal of the History of Ideas 39 (1978): 293–302. +Johnson, Claudia L. Equivocal Beings: Politics, Gender, and Sentimentality in the 1790s. Chicago: University of Chicago Press, 1995. . +Jones, Chris. "Mary Wollstonecraft's Vindications and their political tradition". The Cambridge Companion to Mary Wollstonecraft. Ed. Claudia L. Johnson. Cambridge: Cambridge University Press, 2002. . +Kaplan, Cora. "Mary Wollstonecraft's reception and legacies". The Cambridge Companion to Mary Wollstonecraft. Ed. Claudia L. Johnson. Cambridge: Cambridge University Press, 2002. . +Kaplan, Cora. "Pandora's Box: Subjectivity, Class and Sexuality in Socialist Feminist Criticism". Sea Changes: Essays on Culture and Feminism. London: Verso, 1986. . +Kaplan, Cora. "Wild Nights: Pleasure/Sexuality/Feminism". Sea Changes: Essays on Culture and Feminism. London: Verso, 1986. . +Kelly, Gary. Revolutionary Feminism: The Mind and Career of Mary Wollstonecraft. New York: St. Martin's, 1992. . +Mellor, Anne K. "Mary Wollstonecraft's A Vindication of the Rights of Woman and the women writers of her day". The Cambridge Companion to Mary Wollstonecraft. Ed. Claudia L. Johnson. Cambridge: Cambridge University Press, 2002. . +Pennell, Elizabeth Robins. Life of Mary Wollstonecraft. Boston: Roberts Brothers, 1884. +Poovey, Mary. The Proper Lady and the Woman Writer: Ideology as Style in the Works of Mary Wollstonecraft, Mary Shelley and Jane Austen. Chicago: University of Chicago Press, 1984. . +Sapiro, Virginia. A Vindication of Political Virtue: The Political Theory of Mary Wollstonecraft. Chicago: University of Chicago Press, 1992. . +Sunstein, Emily W. A Different Face: The Life of Mary Wollstonecraft. New York: Harper and Row, 1975. . +Taylor, Barbara. Mary Wollstonecraft and the Feminist Imagination. Cambridge: Cambridge University Press, 2003. . +Todd, Janet. Sensibility: An introduction. London: Methuen, 1986. . +Wardle, Ralph M. Mary Wollstonecraft: A Critical Biography. Lincoln: University of Nebraska Press, 1951. + +External links + +1796 edition of Rights of Woman +Rights of Woman at Project Gutenberg + +Mary Wollstonecraft: A 'Speculative and Dissenting Spirit' by Janet Todd at www.bbc.co.uk +A Vindication of the Rights of Woman: with Strictures on Political and Moral Subjects From the Collections at the Library of Congress + +1792 non-fiction books +Books by Mary Wollstonecraft +Feminist books +Women's rights +History of education in France +1792 in England +First-wave feminism +The Afghan Hound is a hound distinguished by its thick, fine, silky coat, and a tail with a ring curl at the end. The breed is selectively bred for its unique features in the cold mountains of Afghanistan. Its local name is () or (). Other names for this breed are Tāzī, Balkh Hound, Baluchi Hound, and Barakzai Hound. + +The American Kennel Club (AKC) describes the breed as among the most eye-catching of all. The Afghan Hound is an "aloof and dignified aristocrat of sublime beauty." Despite their regal appearance, the Afghan possesses an "endearing streak of silliness and a profound loyalty." + +Admired since ancient times for their beauty, the Afghan Hound's distinctive coat has purpose for the breed. Its shag was developed as protection from the harsh montane climate. Their huge paw-pads served as shock absorbers on the rocky terrain. + +History +The Afghan Hound has been identified as a basal breed that predates the emergence of the modern breeds in the 19th century. It is most closely related to the Saluki. + +Connections with other types and breeds from the same area may provide clues to the history. A name for a desert coursing Afghan Hound, Tazi (Sag-e-Tazi), suggests a shared ancestry with the very similar Tazy breed from the Caspian Sea area of Russia and Turkmenistan. Other types or breeds of similar appearance are the Taigan from the mountainous Tian Shan region on the Chinese border of Afghanistan, and the Barakzay, or Kurram Valley Hound. + +There are at least 13 types known in Afghanistan, and some are being developed (through breeding and record keeping) into modern purebred breeds. + +Once out of Afghanistan, the history of the Afghan Hound breed became entwined with that of the very earliest dog shows and the Kennel Club (UK). Various sighthounds were brought to England in the 1800s by army officers returning from British India and were exhibited at dog shows, which were then just becoming popular, under various names, such as Barukzy hounds. They were also called "Persian Greyhounds" by the English, in reference to their own indigenous sighthound. + +One dog in particular, Zardin, was brought in 1907 from India by Captain John Barff. Zardin became the early ideal for the breed type still referred to as the Persian Greyhound. Zardin was the basis of the writing for the first breed standard in 1912, but this breeding cycle was stopped by World War I. + +Out of the longhaired sighthound types known in Afghanistan, two main strains make up the modern Afghan Hound breed. The first were a group of hounds brought to Scotland from Balochistan by Major and Mrs. G. Bell-Murray and Miss Jean C. Manson in 1920, and they are known as the Bell-Murray strain. These dogs were of the “steppe” or “desert” type and were less heavily coated. + +The second strain was a group of dogs from a kennel in Kabul owned by Mrs. Mary Amps, which she shipped to England in 1925. She and her husband came to Kabul after the Afghan war in 1919, and the foundation sire of her kennel (named Ghazni) in Kabul was a dog that closely resembled Zardin. Her Ghazni strain were the more heavily coated mountain type. Most of the Afghans in the United States were developed from the Ghazni strain from England. The first Afghans in Australia were imported from the United States in 1934, also of the Ghazni strain. The mountain and steppe strains became mixed into the modern Afghan Hound breed, and a new standard was written in 1948, which is still used today. + +The Afghan Hound can also come with a much more "patterned" coat. This descends from the Bell-Murray's and the Ghazni lines, and is displayed in much lighter feathering of coat, deeper saddle (often actually looking like a saddle) and much shorter hair on the face and neck. It is believed that these particular Afghan Hounds were a product of much hotter parts of the country. + +The beauty of Afghan Hound dogs caused them to become highly desirable show dogs and pets, and they are recognised by all of the major kennel clubs in the English-speaking world. One of the Amps Ghazni, Sirdar, won BIS at Crufts in 1928 and 1930. An Afghan Hound was featured on the cover of Life Magazine, November 26, 1945. Afghan Hounds were the most popular in Australia in the 1970s, and won most of the major shows. An Afghan Hound won Best in Show (BIS) at the 1996 World Dog Show in Budapest. Afghan Hounds were BIS at the Westminster Kennel Club Dog Show in 1957 and again in 1983. That win also marked the most recent win at Westminster for breeder-owner-handler, Chris Terrell. + +The Afghan Hound breed is no longer used for hunting, although it can be seen in the sport of lure coursing. + +On August 3, 2005, Korean scientist Hwang Woo-Suk announced that his team of researchers had become the first team to successfully clone a dog, an Afghan Hound named Snuppy. In 2006 Hwang Woo-Suk was dismissed from his university position for fabricating data in his research. Snuppy, nonetheless, was a genuine clone, and thus the first cloned dog in history. + +Description + +The dogs in this breed occur in many different coat colors. A study that mapped the genes of Afghan Hounds and discussed the effect of genes on coat colour in the breed was published in the Journal of Heredity in 2010. + +The Afghan Hound is tall, standing in height and weighing . The coat may be any colour, but white markings, particularly on the head, are discouraged; many individuals have a black facial mask. A specimen may have a beard on the lower jaw, this is known as a "mandarin". Some Afghan Hounds are almost white, but parti-color hounds (white with islands of red or black) are penalized in the AKC standard, but not by the FCI. + +Their long, fine-textured coat requires considerable care and grooming. The long topknot and the shorter-haired saddle on the back of the dog are distinctive features of the Afghan Hound coat. The high hipbones and unique small ring on the end of the tail are also characteristics of the breed. + +The temperament of the typical Afghan Hound can be aloof and dignified, but happy and clownish when playing. This breed, as tends to be the case with sighthounds, has a high prey drive and may kill small animals and livestock. Genomic studies have pointed to the Afghan Hound as one of the oldest of dog breeds. + +The breed has a reputation among dog trainers of having a relatively slow "obedience intelligence"; Stanley Coren, in his book The Intelligence of Dogs, ranked the breed last among 138 breeds mentioned in ability to understand and obey commands, requiring more than 80 repetitions to understand a new command and obeying on the first command less than 25% of the time. Coren noted that Afghan Hounds were consistently ranked among the least obedient dog breeds among all of the trainers he consulted, with a majority (121 out of 199) ranking the Afghan Hound in the lowest ten breeds out of 133 listed. + +Variants + +Khalag Tazi +The Khalag Tazi is a variety of the Afghan Hound introduced to Europe in 1920, when an Indian Army officer, Major G Bell-Murray, brought some animals back from Afghanistan. + +Bakhmull + +Bakhmull (also Bakhmull Tazi or Tazi Bakhmull, also called the Aboriginal Afghan Hound) is a long-haired variety of sighthound. It has been bred mostly in Russia and claimed to represent an Afghan Hound aboriginal to Afghanistan. In Pashto the word means "velvet", applied in reference to the dog's silky coat, which is rather abundant and long on the whole body, except the "saddle" (middle to lower back), front parts of all four legs, and the muzzle. Its color is always fawn, ivory, or white, with a darker "saddle", thus it produces an impression of a (yellowish) dog whose coat color matches the khaki sandstone and limestone of the Hindu Kush mountain landscape and deserts. The following colors are not permissible: red, red with white spots, black, and black with white spots. + +Since the 1980s, the centre of Bakhmull breeding has been Russia, beginning in Moscow, then spreading to various other places in the CIS. The foundation stock was brought to Russia in the 1970s by military men returning from Afghanistan. Natalia Gherasiova (a breeder, of the Blue Dale el Bark Bakhmull kennel, and dog show judge) established the National Bakhmull Club, affiliated with the Russian Federation for Hunting Dogs (RFOS) and Russian Kynological Federation (RKF). A breed standard was first published in 1985, and a shared RFOS–RKF revision was produced in 1997. + +Bakhmulls hunt solo and in couples. Although its coat is long, it does not require much grooming. Paws are well protected from injuries by "feathering" (thick additional paw fur). Its long, velvety coat and its stamina makes more suitable than many breeds for harsh weather. The breed standard calls for "aristocratic gait and a beautiful head with gazelle-like ... eyes". The eyes should be large, brown, slanting upwards, and of almond shape, with rims outlined black. Black coloration is required on the nose and lips for both white and fawn bakhmulls. The dog's height should be between , for bitches. The height at the withers is higher than at the croup. + +Health + +Lifespan +In various surveys conducted within the UK, Afghan Hounds were shown to have an average lifespan of about 12 years, similar to other breeds of their size. In the 2004 UK Kennel Club survey, the most common causes of death were cancer (31%), old age (20%), cardiac (10.5%), and urologic (5%). Those that died of old age had a median lifespan of 12 years, with 12% living to at least 14. + +Health concerns +Major health issues are allergies, cancer, and hip dysplasia. Sensitivity to anesthesia is an issue the Afghan Hound shares with the rest of the sighthound group, as sighthounds have relatively low levels of body fat. Afghan Hounds are also among the dog breeds most likely to develop chylothorax, a rare condition which causes the thoracic ducts to leak, allowing large quantities of chyle fluid to enter the dog's chest cavity. This condition commonly results in a lung-lobe torsion (in which the dog's lung twists within the chest cavity, requiring emergency surgery), due to the breed's typically deep, "barrel"-shaped chest. If not corrected through surgery, chylothorax can ultimately cause fibrosing pleuritis, or a hardening of the organs, due to scar tissue forming around the organs to protect them from the chyle fluid. Chylothorax is often fatal. + +Among other health problems are laryngeal paralysis, dilated cardiomyopathy (twice as common in males as females), and dermatological issues such as testosterone-responsive dermatosis of male dogs (often seen in castrated males), nasal depigmentation (also known as Dudley nose), and skin tumours. Afghans are also prone to Central diabetes insipidus (CDI), hypothyroidism and tricholemmoma, a rare condition which mainly affects older dogs in the Middle Ages. Ocular conditions that can occur include medial canthal pocket syndrome (breed predisposition due to shape of head), corneal dystrophy, cataract and generalized progressive retinal atrophy (GPRA). Afghan myelopathy (causing pelvic limb ataxia) is sometimes reported. + +In popular culture + +Pablo Picasso said that his 1967 statue located in Chicago's Daley Plaza represented the head of an Afghan Hound named Kabul. + +The Afghan hound has been represented in multiple animated feature films and TV shows, including Universal Pictures' Balto (Sylvie), Disney's Lady and the Tramp II: Scamp's Adventure (Ruby), Hasbro Studios's Pound Puppies (Twiggy) and ABC Kids' Bluey (Indy). An Afghan hound also appeared in the movies One Hundred and One Dalmatians, 101 Dalmatians, 102 Dalmatians, and 101 Dalmatians II: Patch's London Adventure. Other examples include Prince Amir of Kinjan from What-a-Mess, Persia from Road Rovers, Burt from Foofur, and Brainy Barker from Krypto the Superdog. Malory Archer in the show Archer also had an Afghan hound named Duchess at some point in her childhood. + +In the 1941 novel Between the Acts, Virginia Woolf uses an Afghan hound named Sohrab to represent aspects of one of the book's human characters. + +The Afghan Hound features prominently in the avant-garde music video of popular French band M83's, "Set in Stone (M83 Remix)". + +An Afghan Hound was also featured on the cover of the 1967 (45 rpm) single "Have Some More Tea/Victor Henry's Cool Book" by British psychedelic rock band The Smoke. + +See also + + Dogs portal + List of dog breeds + Saluki + +References + +Further reading + Afghan Hounds (The World of Dogs) Race L., publisher Kingdom Books, PO Box 15, Waterlooville PO7 6BQ, 1999, England, 240 pages, ch 4, pages 81–83, contributed by Natalia Ghersiova, Russia. + Encyclopedia "Russian Hunting". Scientific edition, publisher "Big Russian Encyclopedia", 1998, pp. 11–12, 187–188 + Indigenous Lop Eared SightHounds From Central Africa To China By Dr. Dominique de Caprona (C) de Caprona 2011 + The reviving and breeding of the ancient Bakhmuul breed from Afghanistan in Russia was appreciated in the US and several respective articles were published in the world known The Afghan Hound Review International Issue November–December 1992 p. 128 + "Two Afghan Hound Breeds In Russia!" The Afghan Hound Review July–August 1995 pp. 102, 104 "The Russian Scene" and in The Afghan Hound Review May–June 2002 pp. 22, 24, 26, 28 "Aboriginal Afghan Hounds". + +External links + + – An active listing of Afghan Hound links. + Afghan Hound – Full Breed Profile + +FCI breeds +Sighthounds +Dog breeds originating in Asia +Animal breeds originating in Afghanistan +Rare dog breeds +The Azawakh is a breed of dog from West Africa. With ancient origins, it is raised throughout the Sahelian zone of Mali, Niger, and Burkina Faso. This region includes the Azawagh Valley for which the breed is named. While commonly associated with the nomadic Tuareg people, they are also bred and owned by other ethnic groups such as the Peulh, Bella, and Hausa. The Azawakh is more related to the Sloughi than it is to the Saluki. + +Description + +Appearance +Slim and elegant, with bone structure and muscles showing through thin skin. Eyes are almond-shaped. + +The coat is very short and almost absent on the belly. Its bone structure shows clearly through the skin and musculature. Its muscles are "dry", meaning that they are quite flat, unlike the Greyhound and Whippet. In this respect it is similar in type to the Saluki. + +Colours +Colours permitted by the Fédération Cynologique Internationale (FCI) breed standard are clear sand to dark fawn/brown, red and brindle (with or without a dark mask), with white bib, tail tip, and white on all feet (which can be tips of toes to high stockings). Since 2015 white stockings that go above the elbow joint are considered disqualifying features in the FCI member countries, as is a white collar or half collar (Irish marked). + +Some conservationists support the idea that in Africa, Azawakhs are still found in a variety of colours such as red, blue fawn (that is, with a lilac cast), grizzle, and, rarely, blue and black with various white markings including Irish marked (white collar) and particolour (mostly white). Because of this wide color variation in the native population, the American standard used by the AKC and UKC allows any color combination found in Africa. (AKC and UKC are not a member of the FCI) + +Movement + +The Azawakh's light, supple, lissome gait is a notable breed characteristic, as is an upright double suspension gallop. + +Health + +Azawakhs are an incredibly sound coursing hound. There is a small occurrence of adult-onset idiopathic epilepsy in the breed. Wobbler disease, or cervical vertebral instability, does rarely occur. + +Reproduction +Unassisted birth of healthy puppies is normal. Litter sizes are usually from four to six puppies, but litters as small as one and as large as ten occur. + +Temperament +Bred by the Tuareg, Fula and various other nomads of the Sahara and sub-Saharan Sahel in the countries of Mali, Niger, Burkina Faso, and southern Algeria, the breed known by the tuaregs as ”Oska” was used there as a guard dog and to hunt gazelle and hare at speeds up to . The austerity of the Sahel environment has ensured that only the most fit dogs survive and has accentuated the breed's ruggedness and independence. Unlike some other sighthounds, the Azawakh is more of a pack hunter and they bump down the quarry with hindquarters when it has been tired out. In role of a guard dog, if an Azawakh senses danger it will bark to alert the other members of the pack, and they will gather together as a pack under the lead of the alpha dog, then chase off or attack the predator. The Sloughi, by comparison, is more of an independent lone hunter and has a high hunting instinct. + +Azawakhs have a range of temperaments from lap dog to quite fierce. Lifelong socialization and gentle handling are critical. Well socialised and trained, they can be good with other dogs, cats, children, and strangers. + +Unlike other sighthounds, the primary function of the Azawakh in its native land is that of protector. It develops an intense bond with its owner, yet can perform independently from its master. With those they accept, Azawakh are gentle and extremely affectionate. With strangers many are reserved and prefer not to be touched, but are not inherently aggressive. Although raised to guard against predators, they do not have innate aggression toward canines or humans unless they are threatened. + +Azawakh have high energy and tremendous endurance. They are excellent training companions for runners. Many Azawakh dislike rain and cold weather. + +Azawakh are pack oriented and form complex social hierarchies. They have tremendous memories and are able to recognize each other after long periods of separation. They can often be found sleeping on top of each other for warmth and companionship. + +Alberto Rossi: "To raise an Azawakh is like building a very fragile construction, which takes a lot of sensibility and can be destroyed from one minute to the next. But every minute it lasts, it fills you with great happiness. Every time I´m sitting in a chair or sofa at least one of my dogs tries to take a seat on my lap. The same happens to those of my guests which they love. In these moments they seem to be the image of calmness, gentleness, and trust. But one should not be deceived about this. In the deepest place of their soul resides something wild and native, and they will remind us about it with the first occasion and we should not forget, even for a moment, not to treat them like a normal dog." + +Breed history + +The breed is relatively uncommon in Europe and North America but there is a growing band of devotees. Azawakh may be registered with the FCI in the USA via the Federación Canófila de Puerto Rico (FCPR). European FCI clubs and the AKC recognize the FCPR as an acceptable registry. The AKC (not a member of the FCI) currently recognizes Azawakh as a Foundation Stock Service breed and they are eligible to participate in AKC-sanctioned Companion & Performance events. The breed will enter the AKC Miscellaneous Class on June 30, 2011. The American Azawakh Association (AAA). is the AKC Parent Club for the Azawakh. Azawakh may be registered with the UKC and ARBA. The breed is not yet registered by CKC. Azawakh are eligible for ASFA and AKC lure coursing and NOFCA open field coursing events. + +See also + Dogs portal + List of dog breeds + +References + +External links + +Rare Breed Network: The Azawakh +American Azawakh Association +Foundation Azawakhs and Other Imports from Africa + +FCI breeds +Sighthounds +Tuareg +Dog breeds originating in Africa +Rare dog breeds +Breeds originating from Indigenous people +Acrylic paint is a fast-drying paint made of pigment suspended in acrylic polymer emulsion and plasticizers, silicone oils, defoamers, stabilizers, or metal soaps. Most acrylic paints are water-based, but become water-resistant when dry. Depending on how much the paint is diluted with water, or modified with acrylic gels, mediums, or pastes, the finished acrylic painting can resemble a watercolor, a gouache, or an oil painting, or have its own unique characteristics not attainable with other media. + +Water-based acrylic paints are used as latex house paints, as latex is the technical term for a suspension of polymer microparticles in water. Interior latex house paints tend to be a combination of binder (sometimes acrylic, vinyl, pva, and others), filler, pigment, and water. Exterior latex house paints may also be a co-polymer blend, but the best exterior water-based paints are 100% acrylic, because of its elasticity and other factors. Vinyl, however, costs half of what 100% acrylic resins cost, and polyvinyl acetate (PVA) is even cheaper, so paint companies make many different combinations of them to match the market. + +History + +Otto Röhm invented acrylic resin, which was quickly transformed into acrylic paint. As early as 1934, the first usable acrylic resin dispersion was developed by German chemical company BASF, and patented by Rohm and Haas. The synthetic paint was first used in the 1940s, combining some of the properties of oil and watercolor. Between 1946 and 1949, Leonard Bocour and Sam Golden invented a solution acrylic paint under the brand Magna paint. These were mineral spirit-based paints. + +Water-based acrylic paints were subsequently sold as latex house paints. + +Soon after the water-based acrylic binders were introduced as house paints, artists and companies alike began to explore the potential of the new binders. Diego Rivera, David Alfaro Siqueiros, and José Clemente Orozco were the first ones who experimented with acrylic paint. This is because they were very impressed with the durability of the acrylic paint. Because of this, artists and companies alike began to produce Politec Acrylic Artists' Colors in Mexico in 1953. According to The Times newspaper, Lancelot Ribeiro pioneered the use of acrylic paints in the UK because of his "increasing impatience" by the 1960s over the time it took for oil paints to dry, as also its "lack of brilliance in its colour potential." He took to the new synthetic plastic bases that commercial paints were beginning to use, and soon got help from manufacturers like ICI, Courtaulds and Geigy. The companies supplied him samples of their latest paints in quantities that he was using three decades later, according to the paper. Initially, the firms thought the PVA compounds would not be needed in commercially viable quantities. But they quickly recognised the potential demand and "so Ribeiro became the godfather of generations of artists using acrylics as an alternative to oils." + +In 1956, José L. Gutiérrez produced Politec Acrylic Artists' Colors in Mexico, and Henry Levison of Cincinnati-based Permanent Pigments Co. produced Liquitex colors. These two product lines were the first acrylic emulsion artists' paints, with modern high-viscosity paints becoming available in the early 1960s. Meanwhile on the other side of the globe, 1958 saw the inception of Vynol Paints Pty Ltd (now Derivan) in Australia, who started producing a water-based artist acrylic called Vynol Colour, followed by Matisse Acrylics in the 1960s. Following that development, Golden came up with a waterborne acrylic paint called "Aquatec". In 1963, George Rowney (part of Daler-Rowney since 1983) was the first manufacturer to introduce artists' acrylic paints in Europe, under the brand name "Cryla". + +Painting with acrylics +Acrylic painters can modify the appearance, hardness, flexibility, texture, and other characteristics of the paint surface by using acrylic mediums or simply by adding water. Watercolor and oil painters also use various mediums, but the range of acrylic mediums is much greater. Acrylics have the ability to bond to many different surfaces, and mediums can be used to modify their binding characteristics. Acrylics can be used on paper, canvas, and a range of other materials; however, their use on engineered woods such as medium-density fiberboard can be problematic because of the porous nature of those surfaces. In these cases, it is recommended that the surface first be sealed with an appropriate sealer. The process of sealing acrylic painting is called varnishing. Artists use removable varnishes over isolation coat to protect paintings from dust, UV, scratches, etc. This process is similar to varnishing an oil painting. + +Acrylics can be applied in thin layers or washes to create effects that resemble watercolors and other water-based mediums. They can also be used to build thick layers of paint — gel and molding paste are sometimes used to create paintings with relief features. Acrylic paints are also used in hobbies such as trains, cars, houses, DIY projects, and human models. People who make such models use acrylic paint to build facial features on dolls or raised details on other types of models. Wet acrylic paint is easily removed from paintbrushes and skin with water, whereas oil paints require the use of a hydrocarbon. + +Acrylics are the most common paints used in grattage, a surrealist technique that began to be used with the advent of this type of paint. Acrylics are used for this purpose because they easily scrape or peel from a surface. + +Painting techniques + +Acrylic artists' paints may be thinned with water or acrylic medium and used as washes in the manner of watercolor paints, but unlike watercolor the washes are not rehydratable once dry. For this reason, acrylics do not lend themselves to the color lifting techniques of gum arabic-based watercolor paints. Instead, the paint is applied in layers, sometimes diluting with water or acrylic medium to allow layers underneath to partially show through. Using an acrylic medium gives the paint more of a rich and glossy appearance, whereas using water makes the paint look more like watercolor and have a matte finish. + +Acrylic paints with gloss or matte finishes are common, although a satin (semi-matte) sheen is most common. Some brands exhibit a range of finishes (e.g. heavy-body paints from Golden, Liquitex, Winsor & Newton and Daler-Rowney); Politec acrylics are fully matte. As with oils, pigment amounts and particle size or shape can affect the paint sheen. Matting agents can also be added during manufacture to dull the finish. If desired, the artist can mix different media with their paints and use topcoats or varnishes to alter or unify sheen. + +When dry, acrylic paint is generally non-removable from a solid surface if it adheres to the surface. Water or mild solvents do not re-solubilize it, although isopropyl alcohol can lift some fresh paint films off. Toluene and acetone can remove paint films, but they do not lift paint stains very well and are not selective. The use of a solvent to remove paint may result in removal of all of the paint layers (acrylic gesso, et cetera). Oils and warm, soapy water can remove acrylic paint from skin. Acrylic paint can be removed from non-porous plastic surfaces, such as miniatures or models using certain cleaning products such as Dettol (containing chloroxylenol 4.8% v/w). + +An acrylic sizing should be used to prime canvas in preparation for painting with acrylic paints, to prevent Support Induced Discoloration (SID). Acrylic paint contains surfactants that can pull up discoloration from a raw canvas, especially in transparent glazed or translucent gelled areas. Gesso alone will not stop SID; a sizing must be applied before using a gesso. + +The viscosity of acrylic can be successfully reduced by using suitable extenders that maintain the integrity of the paint film. There are retarders to slow drying and extend workability time, and flow releases to increase color-blending ability. + +Properties + +Grades + +Commercial acrylic paints come in two grades by manufacturers: + Artist acrylics (professional acrylics) are created and designed to resist chemical reactions from exposure to water, ultraviolet light, and oxygen. Professional-grade acrylics have the most pigment, which allows for more medium manipulation and limits the color shift when mixed with other colors or after drying. + Student acrylics have working characteristics similar to artist acrylics, but with lower pigment concentrations, less-expensive formulas, and fewer available colors. More expensive pigments are generally replicated by hues. Colors are designed to be mixed even though color strength is lower. Hues may not have exactly the same mixing characteristics as full-strength colors. + +Varieties +Heavy body acrylics are typically found in the Artist and Student Grade paints. "Heavy Body" refers to the viscosity or thickness of the paint. They are the best choice for impasto or heavier paint applications and will hold a brush or knife stroke and even a medium stiff peak. Gel Mediums ("pigment-less paints") are also available in various viscosities and used to thicken or thin paints, as well as extend paints and add transparency. +Examples of Heavy Body Acrylics are Matisse Structure Acrylic Colors, Lukas Pastos Acrylics, Liquitex Heavy Body Acrylics and Golden Heavy Body Acrylics. +Medium viscosity acrylics – Fluid acrylics, Soft body acrylics, or High Flow acrylics – have a lower viscosity but generally the same pigmentation as the Heavy Body acrylics. Available in either Artist quality or Craft quality, the cost and quality vary accordingly. These paints are good for watercolor techniques, airbrush application, or when smooth coverage is desired. Fluid acrylics can be mixed with any medium to thicken them for impasto work, or to thin them for glazing applications. +Examples of fluid acrylics include Lukascryl Liquid, Lukascryl Studio, Liquitex Soft Body and Golden Fluid acrylics. +Open acrylics were created to address the one major difference between oil and acrylic paints: the shortened time it takes acrylic paints to dry. Designed by Golden Artist Colors, Inc. with a hydrophilic acrylic resin, these paints can take anywhere from a few hours to a few days, or even weeks, to dry completely, depending on paint thickness, support characteristics, temperature, and humidity. +Iridescent, pearl and interference acrylic colors combine conventional pigments with powdered mica (aluminium silicate) or powdered bronze to achieve complex visual effects. Colors have shimmering or reflective characteristics, depending on the coarseness or fineness of the powder. Iridescent colors are used in fine arts and crafts. +Acrylic gouache is like traditional gouache because it dries to a matte, opaque finish. However, unlike traditional gouache, the acrylic binder makes it water-resistant once it dries. Like craft paint, it will adhere to a variety of surfaces, not only canvas and paper. This paint is typically used by water-colorists, cartoonists, or illustrators, and for decorative or folk art applications. +Examples of acrylic gouache are Lascaux Gouache and Turner Acryl Gouache. +Craft acrylics can be used on surfaces besides canvas, such as wood, metal, fabrics, and ceramics. They are used in decorative painting techniques and faux finishes to decorate objects of ordinary life. Although colors can be mixed, pigments are often not specified. Each color line is formulated instead to achieve a wide range of premixed colors. Craft paints usually employ vinyl or PVA resins to increase adhesion and lower cost. +Interactive acrylics are all-purpose acrylic artists' colors which have the characteristic fast-drying nature of artists' acrylics, but are formulated to allow artists to delay drying when they need more working time, or re-wet their work when they want to do more wet blending. +Exterior acrylics are paints that can withstand outdoor conditions. Like craft acrylics, they adhere to many surfaces. They are more resistant to both water and ultraviolet light. This makes them the acrylic of choice for architectural murals, outdoor signs, and many faux-finishing techniques. +Acrylic glass paint is water-based and semi-permanent, making it a suitable paint for temporary displays on glass windows. +Acrylic enamel paint creates a smooth, hard shell. It can be oven-baked or air dried. It can be permanent if kept away from harsh conditions such as dishwashing. + +Differences between acrylic and oil paint + +The vehicle and binder of oil paints is linseed oil (or another drying oil), whereas acrylic paint has water as the vehicle for an emulsion (suspension) of acrylic polymer, which serves as the binder. Thus, oil paint is said to be "oil-based", whereas acrylic paint is "water-based" (or sometimes "water-borne"). + +The main practical difference between most acrylics and oil paints is the inherent drying time. Oils allow for more time to blend colors and apply even glazes over underpaintings. This slow-drying aspect of oil can be seen as an advantage for certain techniques, but it impedes an artist trying to work quickly. The fast evaporation of water from regular acrylic paint films can be slowed with the use of acrylic retarders. Retarders are generally glycol or glycerin-based additives. The addition of a retarder slows the evaporation rate of the water. + +Oil paints may require the use of solvents such as mineral spirits or turpentine to thin the paint and clean up. These solvents generally have some level of toxicity and can be found objectionable. Relatively recently, water-miscible oil paints have been developed for artists' use. Oil paint films can gradually yellow and lose their flexibility over time creating cracks in the paint film; the "fat over lean" rule must be observed to ensure its durability. + +Oil paint has a higher pigment load than acrylic paint. As linseed oil contains a smaller molecule than acrylic paint, oil paint is able to absorb substantially more pigment. Oil provides a refractive index that is less clear than acrylic dispersions, which imparts a unique "look and feel" to the resultant paint film. Not all the pigments of oil paints are available in acrylics and vice versa, as each medium has different chemical sensitivities. Some historical pigments are alkali sensitive, and therefore cannot be made in an acrylic emulsion; others are just too difficult to formulate. Approximate "hue" color formulations, that do not contain the historical pigments, are typically offered as substitutes. + +Because of acrylic paint's more flexible nature and more consistent drying time between layers, an artist does not have to follow the same rules of oil painting, where more medium must be applied to each layer to avoid cracking. It usually takes 10–20 minutes for one to two layers of acrylic paint to dry, depending on the brand, quality, and humidity levels of the surrounding environment. Some professional grades of acrylic paint can take 20-30 minutes or even more than an hour. Although canvas needs to be properly primed before painting with oils to prevent the paint medium from eventually rotting the canvas, acrylic can be safely applied straight to the canvas. The rapid drying of acrylic paint tends to discourage blending of color and use of wet-in-wet technique as in oil painting. Even though acrylic retarders can slow drying time to several hours, it remains a relatively fast-drying medium and adding too much acrylic retarder can prevent the paint from ever drying properly. + +Meanwhile, acrylic paint is very elastic, which prevents cracking from occurring. Acrylic paint's binder is acrylic polymer emulsion – as this binder dries, the paint remains flexible. + +Another difference between oil and acrylic paints is the versatility offered by acrylic paints. Acrylics are very useful in mixed media, allowing the use of pastel (oil and chalk), charcoal and pen (among others) on top of the dried acrylic painted surface. Mixing other bodies into the acrylic is possible—sand, rice, and even pasta may be incorporated in the artwork. Mixing artist or student grade acrylic paint with household acrylic emulsions is possible, allowing the use of premixed tints straight from the tube or tin, and thereby presenting the painter with a vast color range at their disposal. This versatility is also illustrated by the variety of additional artistic uses for acrylics. Specialized acrylics have been manufactured and used for linoblock printing (acrylic block printing ink has been produced by Derivan since the early 1980s), face painting, airbrushing, watercolor-like techniques, and fabric screen printing. + +Another difference between oil and acrylic paint is the cleanup. Acrylic paint can be cleaned out of a brush with any soap, while oil paint needs a specific type to be sure to get all the oil out of the brushes. Also, it is easier to let a palette with oil paint dry and then scrape the paint off, whereas one can easily clean wet acrylic paint with water. + +Difference between acrylic and watercolor paint +The biggest difference is that acrylic paint is opaque, whereas watercolor paint is translucent in nature. Watercolors take about 5 to 15 minutes to dry while acrylics take about 10 to 20 minutes. In order to change the tone or shade of a watercolor pigment, you change the percentage of water mixed in to the color. For brighter colors, add more water. For darker colors, add less water. In order to create lighter or darker colors with acrylic paints, you add white or black. + +Another difference is that watercolors must be painted onto a porous surface, primarily watercolor paper. Acrylic paints can be used on many different surfaces. + +Both acrylic and watercolor are easy to clean up with water. Acrylic paint should be cleaned with soap and water immediately following use. Watercolor paint can be cleaned with just water. + +See also + +Notes and references + +External links + + Handling and Care Tips for paintings + +American inventions +Visual arts materials +Paints +Watermedia +In physics, angular momentum (sometimes called moment of momentum or rotational momentum) is the rotational analog of linear momentum. It is an important physical quantity because it is a conserved quantity – the total angular momentum of a closed system remains constant. Angular momentum has both a direction and a magnitude, and both are conserved. Bicycles and motorcycles, flying discs, rifled bullets, and gyroscopes owe their useful properties to conservation of angular momentum. Conservation of angular momentum is also why hurricanes form spirals and neutron stars have high rotational rates. In general, conservation limits the possible motion of a system, but it does not uniquely determine it. + +The three-dimensional angular momentum for a point particle is classically represented as a pseudovector , the cross product of the particle's position vector (relative to some origin) and its momentum vector; the latter is in Newtonian mechanics. Unlike linear momentum, angular momentum depends on where this origin is chosen, since the particle's position is measured from it. + +Angular momentum is an extensive quantity; that is, the total angular momentum of any composite system is the sum of the angular momenta of its constituent parts. For a continuous rigid body or a fluid, the total angular momentum is the volume integral of angular momentum density (angular momentum per unit volume in the limit as volume shrinks to zero) over the entire body. + +Similar to conservation of linear momentum, where it is conserved if there is no external force, angular momentum is conserved if there is no external torque. Torque can be defined as the rate of change of angular momentum, analogous to force. The net external torque on any system is always equal to the total torque on the system; in other words, the sum of all internal torques of any system is always 0 (this is the rotational analogue of Newton's third law of motion). Therefore, for a closed system (where there is no net external torque), the total torque on the system must be 0, which means that the total angular momentum of the system is constant. The change in angular momentum for a particular interaction is called angular impulse, sometimes twirl. Angular impulse is the angular analog of (linear) impulse. + +Examples +The trivial case of the angular momentum of a body in an orbit is given by + +where is the mass of the orbiting object, is the orbit's frequency and is the orbit's radius. + +The angular momentum of a uniform rigid sphere rotating around its axis instead is given by + +where is the sphere's mass, is the frequency of rotation and is the sphere's radius. + +Thus, for example, the orbital angular momentum of the Earth with respect to the Sun is about 2.66 × 1040 kg⋅m2⋅s−1, while its rotational angular momentum is about 7.05 × 1033 kg⋅m2⋅s−1. + +In the case of a uniform rigid sphere rotating around its axis, if, instead of its mass, its density is known, the angular momentum is given by + +where is the sphere's density, is the frequency of rotation and is the sphere's radius. + +In the simplest case of a spinning disk, the angular momentum is given by + +where is the disk's mass, is the frequency of rotation and is the disk's radius. + +If instead the disk rotates about its diameter (e.g. coin toss), its angular momentum is given by + +Definition in classical mechanics + +Just as for angular velocity, there are two special types of angular momentum of an object: the spin angular momentum is the angular momentum about the object's centre of mass, while the orbital angular momentum is the angular momentum about a chosen center of rotation. The Earth has an orbital angular momentum by nature of revolving around the Sun, and a spin angular momentum by nature of its daily rotation around the polar axis. The total angular momentum is the sum of the spin and orbital angular momenta. In the case of the Earth the primary conserved quantity is the total angular momentum of the solar system because angular momentum is exchanged to a small but important extent among the planets and the Sun. The orbital angular momentum vector of a point particle is always parallel and directly proportional to its orbital angular velocity vector ω, where the constant of proportionality depends on both the mass of the particle and its distance from origin. The spin angular momentum vector of a rigid body is proportional but not always parallel to the spin angular velocity vector Ω, making the constant of proportionality a second-rank tensor rather than a scalar. + +Orbital angular momentum in two dimensions + +Angular momentum is a vector quantity (more precisely, a pseudovector) that represents the product of a body's rotational inertia and rotational velocity (in radians/sec) about a particular axis. However, if the particle's trajectory lies in a single plane, it is sufficient to discard the vector nature of angular momentum, and treat it as a scalar (more precisely, a pseudoscalar). Angular momentum can be considered a rotational analog of linear momentum. Thus, where linear momentum is proportional to mass and linear speed + +angular momentum is proportional to moment of inertia and angular speed measured in radians per second. + +Unlike mass, which depends only on amount of matter, moment of inertia depends also on the position of the axis of rotation and the distribution of the matter. Unlike linear velocity, which does not depend upon the choice of origin, orbital angular velocity is always measured with respect to a fixed origin. Therefore, strictly speaking, should be referred to as the angular momentum relative to that center. + +In the case of circular motion of a single particle, we can use and to expand angular momentum as reducing to: + +the product of the radius of rotation and the linear momentum of the particle , where is the linear (tangential) speed. + +This simple analysis can also apply to non-circular motion if one uses the component of the motion perpendicular to the radius vector: + +where is the perpendicular component of the motion. Expanding, rearranging, and reducing, angular momentum can also be expressed, + +where is the length of the moment arm, a line dropped perpendicularly from the origin onto the path of the particle. It is this definition, , to which the term moment of momentum refers. + +Scalar angular momentum from Lagrangian mechanics +Another approach is to define angular momentum as the conjugate momentum (also called canonical momentum) of the angular coordinate expressed in the Lagrangian of the mechanical system. Consider a mechanical system with a mass constrained to move in a circle of radius in the absence of any external force field. The kinetic energy of the system is + +And the potential energy is + +Then the Lagrangian is + +The generalized momentum "canonically conjugate to" the coordinate is defined by + +Orbital angular momentum in three dimensions + +To completely define orbital angular momentum in three dimensions, it is required to know the rate at which the position vector sweeps out angle, the direction perpendicular to the instantaneous plane of angular displacement, and the mass involved, as well as how this mass is distributed in space. By retaining this vector nature of angular momentum, the general nature of the equations is also retained, and can describe any sort of three-dimensional motion about the center of rotation – circular, linear, or otherwise. In vector notation, the orbital angular momentum of a point particle in motion about the origin can be expressed as: + +where + is the moment of inertia for a point mass, + is the orbital angular velocity of the particle about the origin, + is the position vector of the particle relative to the origin, and , + is the linear velocity of the particle relative to the origin, and + is the mass of the particle. + +This can be expanded, reduced, and by the rules of vector algebra, rearranged: + +which is the cross product of the position vector and the linear momentum of the particle. By the definition of the cross product, the vector is perpendicular to both and . It is directed perpendicular to the plane of angular displacement, as indicated by the right-hand rule – so that the angular velocity is seen as counter-clockwise from the head of the vector. Conversely, the vector defines the plane in which and lie. + +By defining a unit vector perpendicular to the plane of angular displacement, a scalar angular speed results, where + and + where is the perpendicular component of the motion, as above. + +The two-dimensional scalar equations of the previous section can thus be given direction: + +and for circular motion, where all of the motion is perpendicular to the radius . + +In the spherical coordinate system the angular momentum vector expresses as + +Angular momentum in any number of dimensions + +Angular momentum can be defined in terms of the cross product only in three dimensions. Defining it as the bivector , where is the exterior product, is valid in any number of dimensions. This exterior product is equivalent to an antisymmetric tensor of degree 2, which also applies in any number of dimensions. Namely, if is a position vector and is the linear momentum vector, then we can define + +In the general case of summed angular momenta from multiple particles, this antisymmetric tensor has independent components (degrees of freedom), where is the number of dimensions. In the usual three-dimensional case it has 3 independent components, which allows us to identify it with a 3 dimensional pseudovector . The components of this vector relate to the components of the rank 2 tensor as follows: + +Analogy to linear momentum +Angular momentum can be described as the rotational analog of linear momentum. Like linear momentum it involves elements of mass and displacement. Unlike linear momentum it also involves elements of position and shape. + +Many problems in physics involve matter in motion about some certain point in space, be it in actual rotation about it, or simply moving past it, where it is desired to know what effect the moving matter has on the point—can it exert energy upon it or perform work about it? Energy, the ability to do work, can be stored in matter by setting it in motion—a combination of its inertia and its displacement. Inertia is measured by its mass, and displacement by its velocity. Their product, + +is the matter's momentum. Referring this momentum to a central point introduces a complication: the momentum is not applied to the point directly. For instance, a particle of matter at the outer edge of a wheel is, in effect, at the end of a lever of the same length as the wheel's radius, its momentum turning the lever about the center point. This imaginary lever is known as the moment arm. It has the effect of multiplying the momentum's effort in proportion to its length, an effect known as a moment. Hence, the particle's momentum referred to a particular point, + +is the angular momentum, sometimes called, as here, the moment of momentum of the particle versus that particular center point. The equation combines a moment (a mass turning moment arm ) with a linear (straight-line equivalent) speed . Linear speed referred to the central point is simply the product of the distance and the angular speed versus the point: another moment. Hence, angular momentum contains a double moment: Simplifying slightly, the quantity is the particle's moment of inertia, sometimes called the second moment of mass. It is a measure of rotational inertia. + +The above analogy of the translational momentum and rotational momentum can be expressed in vector form: + + for linear motion + for rotation + +The direction of momentum is related to the direction of the velocity for linear movement. The direction of angular momentum is related to the angular velocity of the rotation. + +Because moment of inertia is a crucial part of the spin angular momentum, the latter necessarily includes all of the complications of the former, which is calculated by multiplying elementary bits of the mass by the squares of their distances from the center of rotation. Therefore, the total moment of inertia, and the angular momentum, is a complex function of the configuration of the matter about the center of rotation and the orientation of the rotation for the various bits. + +For a rigid body, for instance a wheel or an asteroid, the orientation of rotation is simply the position of the rotation axis versus the matter of the body. It may or may not pass through the center of mass, or it may lie completely outside of the body. For the same body, angular momentum may take a different value for every possible axis about which rotation may take place. It reaches a minimum when the axis passes through the center of mass. + +For a collection of objects revolving about a center, for instance all of the bodies of the Solar System, the orientations may be somewhat organized, as is the Solar System, with most of the bodies' axes lying close to the system's axis. Their orientations may also be completely random. + +In brief, the more mass and the farther it is from the center of rotation (the longer the moment arm), the greater the moment of inertia, and therefore the greater the angular momentum for a given angular velocity. In many cases the moment of inertia, and hence the angular momentum, can be simplified by, +where is the radius of gyration, the distance from the axis at which the entire mass may be considered as concentrated. + +Similarly, for a point mass the moment of inertia is defined as, +where is the radius of the point mass from the center of rotation, + +and for any collection of particles as the sum, + +Angular momentum's dependence on position and shape is reflected in its units versus linear momentum: kg⋅m2/s or N⋅m⋅s for angular momentum versus kg⋅m/s or N⋅s for linear momentum. When calculating angular momentum as the product of the moment of inertia times the angular velocity, the angular velocity must be expressed in radians per second, where the radian assumes the dimensionless value of unity. (When performing dimensional analysis, it may be productive to use orientational analysis which treats radians as a base unit, but this is not done in the International system of units). The units if angular momentum can be interpreted as torque⋅time. An object with angular momentum of can be reduced to zero angular velocity by an angular impulse of . + +The plane perpendicular to the axis of angular momentum and passing through the center of mass is sometimes called the invariable plane, because the direction of the axis remains fixed if only the interactions of the bodies within the system, free from outside influences, are considered. One such plane is the invariable plane of the Solar System. + +Angular momentum and torque + +Newton's second law of motion can be expressed mathematically, + +or force = mass × acceleration. The rotational equivalent for point particles may be derived as follows: + +which means that the torque (i.e. the time derivative of the angular momentum) is + +Because the moment of inertia is , it follows that , and which, reduces to + +This is the rotational analog of Newton's second law. Note that the torque is not necessarily proportional or parallel to the angular acceleration (as one might expect). The reason for this is that the moment of inertia of a particle can change with time, something that cannot occur for ordinary mass. + +Conservation of angular momentum + +General considerations +A rotational analog of Newton's third law of motion might be written, "In a closed system, no torque can be exerted on any matter without the exertion on some other matter of an equal and opposite torque about the same axis." Hence, angular momentum can be exchanged between objects in a closed system, but total angular momentum before and after an exchange remains constant (is conserved). + +Seen another way, a rotational analogue of Newton's first law of motion might be written, "A rigid body continues in a state of uniform rotation unless acted by an external influence." Thus with no external influence to act upon it, the original angular momentum of the system remains constant. + +The conservation of angular momentum is used in analyzing central force motion. If the net force on some body is directed always toward some point, the center, then there is no torque on the body with respect to the center, as all of the force is directed along the radius vector, and none is perpendicular to the radius. Mathematically, torque because in this case and are parallel vectors. Therefore, the angular momentum of the body about the center is constant. This is the case with gravitational attraction in the orbits of planets and satellites, where the gravitational force is always directed toward the primary body and orbiting bodies conserve angular momentum by exchanging distance and velocity as they move about the primary. Central force motion is also used in the analysis of the Bohr model of the atom. + +For a planet, angular momentum is distributed between the spin of the planet and its revolution in its orbit, and these are often exchanged by various mechanisms. The conservation of angular momentum in the Earth–Moon system results in the transfer of angular momentum from Earth to Moon, due to tidal torque the Moon exerts on the Earth. This in turn results in the slowing down of the rotation rate of Earth, at about 65.7 nanoseconds per day, and in gradual increase of the radius of Moon's orbit, at about 3.82 centimeters per year. + +The conservation of angular momentum explains the angular acceleration of an ice skater as they bring their arms and legs close to the vertical axis of rotation. By bringing part of the mass of their body closer to the axis, they decrease their body's moment of inertia. Because angular momentum is the product of moment of inertia and angular velocity, if the angular momentum remains constant (is conserved), then the angular velocity (rotational speed) of the skater must increase. + +The same phenomenon results in extremely fast spin of compact stars (like white dwarfs, neutron stars and black holes) when they are formed out of much larger and slower rotating stars. + +Conservation is not always a full explanation for the dynamics of a system but is a key constraint. For example, a spinning top is subject to gravitational torque making it lean over and change the angular momentum about the nutation axis, but neglecting friction at the point of spinning contact, it has a conserved angular momentum about its spinning axis, and another about its precession axis. Also, in any planetary system, the planets, star(s), comets, and asteroids can all move in numerous complicated ways, but only so that the angular momentum of the system is conserved. + +Noether's theorem states that every conservation law is associated with a symmetry (invariant) of the underlying physics. The symmetry associated with conservation of angular momentum is rotational invariance. The fact that the physics of a system is unchanged if it is rotated by any angle about an axis implies that angular momentum is conserved. + +Relation to Newton's second law of motion + +While angular momentum total conservation can be understood separately from Newton's laws of motion as stemming from Noether's theorem in systems symmetric under rotations, it can also be understood simply as an efficient method of calculation of results that can also be otherwise arrived at directly from Newton's second law, together with laws governing the forces of nature (such as Newton's third law, Maxwell's equations and Lorentz force). Indeed, given initial conditions of position and velocity for every point, and the forces at such a condition, one may use Newton's second law to calculate the second derivative of position, and solving for this gives full information on the development of the physical system with time. Note, however, that this is no longer true in quantum mechanics, due to the existence of particle spin, which is angular momentum that cannot be described by the cumulative effect of point-like motions in space. + +As an example, consider decreasing of the moment of inertia, e.g. when a figure skater is pulling in their hands, speeding up the circular motion. In terms of angular momentum conservation, we have, for angular momentum L, moment of inertia I and angular velocity ω: + +Using this, we see that the change requires an energy of: + +so that a decrease in the moment of inertia requires investing energy. + +This can be compared to the work done as calculated using Newton's laws. Each point in the rotating body is accelerating, at each point of time, with radial acceleration of: + +Let us observe a point of mass m, whose position vector relative to the center of motion is perpendicular to the z-axis at a given point of time, and is at a distance z. The centripetal force on this point, keeping the circular motion, is: + +Thus the work required for moving this point to a distance dz farther from the center of motion is: + +For a non-pointlike body one must integrate over this, with m replaced by the mass density per unit z. This gives: + +which is exactly the energy required for keeping the angular momentum conserved. + +Note, that the above calculation can also be performed per mass, using kinematics only. Thus the phenomena of figure skater accelerating tangential velocity while pulling their hands in, can be understood as follows in layman's language: The skater's palms are not moving in a straight line, so they are constantly accelerating inwards, but do not gain additional speed because the accelerating is always done when their motion inwards is zero. However, this is different when pulling the palms closer to the body: The acceleration due to rotation now increases the speed; but because of the rotation, the increase in speed does not translate to a significant speed inwards, but to an increase of the rotation speed. + +In Lagrangian formalism +In Lagrangian mechanics, angular momentum for rotation around a given axis, is the conjugate momentum of the generalized coordinate of the angle around the same axis. For example, , the angular momentum around the z axis, is: + +where is the Lagrangian and is the angle around the z axis. + +Note that , the time derivative of the angle, is the angular velocity . Ordinarily, the Lagrangian depends on the angular velocity through the kinetic energy: The latter can be written by separating the velocity to its radial and tangential part, with the tangential part at the x-y plane, around the z-axis, being equal to: + +where the subscript i stands for the i-th body, and m, vT and ωz stand for mass, tangential velocity around the z-axis and angular velocity around that axis, respectively. + +For a body that is not point-like, with density ρ, we have instead: + +where integration runs over the area of the body, and Iz is the moment of inertia around the z-axis. + +Thus, assuming the potential energy does not depend on ωz (this assumption may fail for electromagnetic systems), we have the angular momentum of the ith object: + +We have thus far rotated each object by a separate angle; we may also define an overall angle θz by which we rotate the whole system, thus rotating also each object around the z-axis, and have the overall angular momentum: + +From Euler–Lagrange equations it then follows that: + +Since the lagrangian is dependent upon the angles of the object only through the potential, we have: + +which is the torque on the ith object. + +Suppose the system is invariant to rotations, so that the potential is independent of an overall rotation by the angle θz (thus it may depend on the angles of objects only through their differences, in the form ). We therefore get for the total angular momentum: + +And thus the angular momentum around the z-axis is conserved. + +This analysis can be repeated separately for each axis, giving conversation of the angular momentum vector. However, the angles around the three axes cannot be treated simultaneously as generalized coordinates, since they are not independent; in particular, two angles per point suffice to determine its position. While it is true that in the case of a rigid body, fully describing it requires, in addition to three translational degrees of freedom, also specification of three rotational degrees of freedom; however these cannot be defined as rotations around the Cartesian axes (see Euler angles). This caveat is reflected in quantum mechanics in the non-trivial commutation relations of the different components of the angular momentum operator. + +In Hamiltonian formalism +Equivalently, in Hamiltonian mechanics the Hamiltonian can be described as a function of the angular momentum. As before, the part of the kinetic energy related to rotation around the z-axis for the ith object is: + +which is analogous to the energy dependence upon momentum along the z-axis, . + +Hamilton's equations relate the angle around the z-axis to its conjugate momentum, the angular momentum around the same axis: + +The first equation gives + +And so we get the same results as in the Lagrangian formalism. + +Note, that for combining all axes together, we write the kinetic energy as: + +where pr is the momentum in the radial direction, and the moment of inertia is a 3-dimensional matrix; bold letters stand for 3-dimensional vectors. + +For point-like bodies we have: + +This form of the kinetic energy part of the Hamiltonian is useful in analyzing central potential problems, and is easily transformed to a quantum mechanical work frame (e.g. in the hydrogen atom problem). + +Angular momentum in orbital mechanics + +While in classical mechanics the language of angular momentum can be replaced by Newton's laws of motion, it is particularly useful for motion in central potential such as planetary motion in the solar system. Thus, the orbit of a planet in the solar system is defined by its energy, angular momentum and angles of the orbit major axis relative to a coordinate frame. + +In astrodynamics and celestial mechanics, a quantity closely related to angular momentum is defined as + +called specific angular momentum. Note that Mass is often unimportant in orbital mechanics calculations, because motion of a body is determined by gravity. The primary body of the system is often so much larger than any bodies in motion about it that the gravitational effect of the smaller bodies on it can be neglected; it maintains, in effect, constant velocity. The motion of all bodies is affected by its gravity in the same way, regardless of mass, and therefore all move approximately the same way under the same conditions. + +Solid bodies +Angular momentum is also an extremely useful concept for describing rotating rigid bodies such as a gyroscope or a rocky planet. +For a continuous mass distribution with density function ρ(r), a differential volume element dV with position vector r within the mass has a mass element dm = ρ(r)dV. Therefore, the infinitesimal angular momentum of this element is: + +and integrating this differential over the volume of the entire mass gives its total angular momentum: + +In the derivation which follows, integrals similar to this can replace the sums for the case of continuous mass. + +Collection of particles + +For a collection of particles in motion about an arbitrary origin, it is informative to develop the equation of angular momentum by resolving their motion into components about their own center of mass and about the origin. Given, + is the mass of particle , + is the position vector of particle w.r.t. the origin, + is the velocity of particle w.r.t. the origin, + is the position vector of the center of mass w.r.t. the origin, + is the velocity of the center of mass w.r.t. the origin, + is the position vector of particle w.r.t. the center of mass, + is the velocity of particle w.r.t. the center of mass, + +The total mass of the particles is simply their sum, + +The position vector of the center of mass is defined by, + +By inspection, + and + +The total angular momentum of the collection of particles is the sum of the angular momentum of each particle, + +Expanding , + + +Expanding , + + +It can be shown that (see sidebar), + + and +therefore the second and third terms vanish, + + +The first term can be rearranged, + + +and total angular momentum for the collection of particles is finally, + +The first term is the angular momentum of the center of mass relative to the origin. Similar to , below, it is the angular momentum of one particle of mass M at the center of mass moving with velocity V. The second term is the angular momentum of the particles moving relative to the center of mass, similar to , below. The result is general—the motion of the particles is not restricted to rotation or revolution about the origin or center of mass. The particles need not be individual masses, but can be elements of a continuous distribution, such as a solid body. + +Rearranging equation () by vector identities, multiplying both terms by "one", and grouping appropriately, + +gives the total angular momentum of the system of particles in terms of moment of inertia and angular velocity , + +Single particle case +In the case of a single particle moving about the arbitrary origin, + + and equations () and () for total angular momentum reduce to, + +Case of a fixed center of mass +For the case of the center of mass fixed in space with respect to the origin, + + and equations () and () for total angular momentum reduce to, + +Angular momentum in general relativity + +In modern (20th century) theoretical physics, angular momentum (not including any intrinsic angular momentum – see below) is described using a different formalism, instead of a classical pseudovector. In this formalism, angular momentum is the 2-form Noether charge associated with rotational invariance. As a result, angular momentum is not conserved for general curved spacetimes, unless it happens to be asymptotically rotationally invariant. + +In classical mechanics, the angular momentum of a particle can be reinterpreted as a plane element: + +in which the exterior product (∧) replaces the cross product (×) (these products have similar characteristics but are nonequivalent). This has the advantage of a clearer geometric interpretation as a plane element, defined using the vectors x and p, and the expression is true in any number of dimensions. In Cartesian coordinates: + +or more compactly in index notation: + +The angular velocity can also be defined as an anti-symmetric second order tensor, with components ωij. The relation between the two anti-symmetric tensors is given by the moment of inertia which must now be a fourth order tensor: + +Again, this equation in L and ω as tensors is true in any number of dimensions. This equation also appears in the geometric algebra formalism, in which L and ω are bivectors, and the moment of inertia is a mapping between them. + +In relativistic mechanics, the relativistic angular momentum of a particle is expressed as an anti-symmetric tensor of second order: + +in terms of four-vectors, namely the four-position X and the four-momentum P, and absorbs the above L together with the moment of mass, i.e., the product of the relativistic mass of the particle and its centre of mass, which can be thought of as describing the motion of its centre of mass, since mass–energy is conserved. + +In each of the above cases, for a system of particles the total angular momentum is just the sum of the individual particle angular momenta, and the centre of mass is for the system. + +Angular momentum in quantum mechanics + +In quantum mechanics, angular momentum (like other quantities) is expressed as an operator, and its one-dimensional projections have quantized eigenvalues. Angular momentum is subject to the Heisenberg uncertainty principle, implying that at any time, only one projection (also called "component") can be measured with definite precision; the other two then remain uncertain. Because of this, the axis of rotation of a quantum particle is undefined. Quantum particles do possess a type of non-orbital angular momentum called "spin", but this angular momentum does not correspond to a spinning motion. In relativistic quantum mechanics the above relativistic definition becomes a tensorial operator. + +Spin, orbital, and total angular momentum + +The classical definition of angular momentum as can be carried over to quantum mechanics, by reinterpreting r as the quantum position operator and p as the quantum momentum operator. L is then an operator, specifically called the orbital angular momentum operator. The components of the angular momentum operator satisfy the commutation relations of the Lie algebra so(3). Indeed, these operators are precisely the infinitesimal action of the rotation group on the quantum Hilbert space. (See also the discussion below of the angular momentum operators as the generators of rotations.) + +However, in quantum physics, there is another type of angular momentum, called spin angular momentum, represented by the spin operator S. Spin is often depicted as a particle literally spinning around an axis, but this is a misleading and inaccurate picture: spin is an intrinsic property of a particle, unrelated to any sort of motion in space and fundamentally different from orbital angular momentum. All elementary particles have a characteristic spin (possibly zero), and almost all elementary particles have nonzero spin. For example electrons have "spin 1/2" (this actually means "spin ħ/2"), photons have "spin 1" (this actually means "spin ħ"), and pi-mesons have spin 0. + +Finally, there is total angular momentum J, which combines both the spin and orbital angular momentum of all particles and fields. (For one particle, .) Conservation of angular momentum applies to J, but not to L or S; for example, the spin–orbit interaction allows angular momentum to transfer back and forth between L and S, with the total remaining constant. Electrons and photons need not have integer-based values for total angular momentum, but can also have half-integer values. + +In molecules the total angular momentum F is the sum of the rovibronic (orbital) angular momentum N, the electron spin angular momentum S, and the nuclear spin angular momentum I. For electronic singlet states the rovibronic angular momentum is denoted J rather than N. As explained by Van Vleck, the components of the molecular rovibronic angular momentum referred to molecule-fixed axes have different commutation relations from those for the components about space-fixed axes. + +Quantization + +In quantum mechanics, angular momentum is quantized – that is, it cannot vary continuously, but only in "quantum leaps" between certain allowed values. For any system, the following restrictions on measurement results apply, where is the reduced Planck constant and is any Euclidean vector such as x, y, or z: + +The reduced Planck constant is tiny by everyday standards, about 10−34 J s, and therefore this quantization does not noticeably affect the angular momentum of macroscopic objects. However, it is very important in the microscopic world. For example, the structure of electron shells and subshells in chemistry is significantly affected by the quantization of angular momentum. + +Quantization of angular momentum was first postulated by Niels Bohr in his model of the atom and was later predicted by Erwin Schrödinger in his Schrödinger equation. + +Uncertainty +In the definition , six operators are involved: The position operators , , , and the momentum operators , , . However, the Heisenberg uncertainty principle tells us that it is not possible for all six of these quantities to be known simultaneously with arbitrary precision. Therefore, there are limits to what can be known or measured about a particle's angular momentum. It turns out that the best that one can do is to simultaneously measure both the angular momentum vector's magnitude and its component along one axis. + +The uncertainty is closely related to the fact that different components of an angular momentum operator do not commute, for example . (For the precise commutation relations, see angular momentum operator.) + +Total angular momentum as generator of rotations +As mentioned above, orbital angular momentum L is defined as in classical mechanics: , but total angular momentum J is defined in a different, more basic way: J is defined as the "generator of rotations". More specifically, J is defined so that the operator + +is the rotation operator that takes any system and rotates it by angle about the axis . (The "exp" in the formula refers to operator exponential.) To put this the other way around, whatever our quantum Hilbert space is, we expect that the rotation group SO(3) will act on it. There is then an associated action of the Lie algebra so(3) of SO(3); the operators describing the action of so(3) on our Hilbert space are the (total) angular momentum operators. + +The relationship between the angular momentum operator and the rotation operators is the same as the relationship between Lie algebras and Lie groups in mathematics. The close relationship between angular momentum and rotations is reflected in Noether's theorem that proves that angular momentum is conserved whenever the laws of physics are rotationally invariant. + +Angular momentum in electrodynamics + +When describing the motion of a charged particle in an electromagnetic field, the canonical momentum P (derived from the Lagrangian for this system) is not gauge invariant. As a consequence, the canonical angular momentum L = r × P is not gauge invariant either. Instead, the momentum that is physical, the so-called kinetic momentum (used throughout this article), is (in SI units) + +where e is the electric charge of the particle and A the magnetic vector potential of the electromagnetic field. The gauge-invariant angular momentum, that is kinetic angular momentum, is given by + +The interplay with quantum mechanics is discussed further in the article on canonical commutation relations. + +Angular momentum in optics +In classical Maxwell electrodynamics the Poynting vector +is a linear momentum density of electromagnetic field. + +The angular momentum density vector is given by a vector product +as in classical mechanics: + +The above identities are valid locally, i.e. in each space point in a given moment . + +Angular momentum in nature and the cosmos + +Tropical cyclones and other related weather phenomena involve conservation of angular momentum in order to explain the dynamics. Winds revolve slowly around low pressure systems, mainly due to the coriolis effect. If the low pressure intensifies and the slowly circulating air is drawn toward the center, the molecules must speed up in order to conserve angular momentum. By the time they reach the center, the speeds become destructive. + +Johannes Kepler determined the laws of planetary motion without knowledge of conservation of momentum. However, not long after his discovery their derivation was determined from conservation of angular momentum. Planets move more slowly the further they are out in their elliptical orbits, which is explained intuitively by the fact that orbital angular momentum is proportional to the radius of the orbit. Since the mass does not change and the angular momentum is conserved, the velocity drops. + +Tidal acceleration is an effect of the tidal forces between an orbiting natural satellite (e.g. the Moon) and the primary planet that it orbits (e.g. Earth). The gravitational torque between the Moon and the tidal bulge of Earth causes the Moon to be constantly promoted to a slightly higher orbit (~3.8 cm per year) and Earth to be decelerated (by −25.858 ± 0.003″/cy²) in its rotation (the length of the day increases by ~1.7 ms per century, +2.3 ms from tidal effect and −0.6 ms from post-glacial rebound). The Earth loses angular momentum which is transferred to the Moon such that the overall angular momentum is conserved. + +Angular momentum in engineering and technology + +Examples of using conservation of angular momentum for practical advantage are abundant. In engines such as steam engines or internal combustion engines, a flywheel is needed to efficiently convert the lateral motion of the pistons to rotational motion. + +Inertial navigation systems explicitly use the fact that angular momentum is conserved with respect to the inertial frame of space. Inertial navigation is what enables submarine trips under the polar ice cap, but are also crucial to all forms of modern navigation. + +Rifled bullets use the stability provided by conservation of angular momentum to be more true in their trajectory. The invention of rifled firearms and cannons gave their users significant strategic advantage in battle, and thus were a technological turning point in history. + +History +Isaac Newton, in the Principia, hinted at angular momentum in his examples of the first law of motion,A top, whose parts by their cohesion are perpetually drawn aside from rectilinear motions, does not cease its rotation, otherwise than as it is retarded by the air. The greater bodies of the planets and comets, meeting with less resistance in more free spaces, preserve their motions both progressive and circular for a much longer time.He did not further investigate angular momentum directly in the Principia, saying:From such kind of reflexions also sometimes arise the circular motions of bodies about their own centres. But these are cases which I do not consider in what follows; and it would be too tedious to demonstrate every particular that relates to this subject.However, his geometric proof of the law of areas is an outstanding example of Newton's genius, and indirectly proves angular momentum conservation in the case of a central force. + +The Law of Areas + +Newton's derivation + +As a planet orbits the Sun, the line between the Sun and the planet sweeps out equal areas in equal intervals of time. This had been known since Kepler expounded his second law of planetary motion. Newton derived a unique geometric proof, and went on to show that the attractive force of the Sun's gravity was the cause of all of Kepler's laws. + +During the first interval of time, an object is in motion from point A to point B. Undisturbed, it would continue to point c during the second interval. When the object arrives at B, it receives an impulse directed toward point S. The impulse gives it a small added velocity toward S, such that if this were its only velocity, it would move from B to V during the second interval. By the rules of velocity composition, these two velocities add, and point C is found by construction of parallelogram BcCV. Thus the object's path is deflected by the impulse so that it arrives at point C at the end of the second interval. Because the triangles SBc and SBC have the same base SB and the same height Bc or VC, they have the same area. By symmetry, triangle SBc also has the same area as triangle SAB, therefore the object has swept out equal areas SAB and SBC in equal times. + +At point C, the object receives another impulse toward S, again deflecting its path during the third interval from d to D. Thus it continues to E and beyond, the triangles SAB, SBc, SBC, SCd, SCD, SDe, SDE all having the same area. Allowing the time intervals to become ever smaller, the path ABCDE approaches indefinitely close to a continuous curve. + +Note that because this derivation is geometric, and no specific force is applied, it proves a more general law than Kepler's second law of planetary motion. It shows that the Law of Areas applies to any central force, attractive or repulsive, continuous or non-continuous, or zero. + +Conservation of angular momentum in the Law of Areas +The proportionality of angular momentum to the area swept out by a moving object can be understood by realizing that the bases of the triangles, that is, the lines from S to the object, are equivalent to the radius , and that the heights of the triangles are proportional to the perpendicular component of velocity . Hence, if the area swept per unit time is constant, then by the triangular area formula , the product and therefore the product are constant: if and the base length are decreased, and height must increase proportionally. Mass is constant, therefore angular momentum is conserved by this exchange of distance and velocity. + +In the case of triangle SBC, area is equal to (SB)(VC). Wherever C is eventually located due to the impulse applied at B, the product (SB)(VC), and therefore remain constant. Similarly so for each of the triangles. + +Another areal proof of conservation of momentum for any central force uses Mamikon's sweeping tangents theorem. + +After Newton +Leonhard Euler, Daniel Bernoulli, and Patrick d'Arcy all understood angular momentum in terms of conservation of areal velocity, a result of their analysis of Kepler's second law of planetary motion. It is unlikely that they realized the implications for ordinary rotating matter. + +In 1736 Euler, like Newton, touched on some of the equations of angular momentum in his Mechanica without further developing them. + +Bernoulli wrote in a 1744 letter of a "moment of rotational motion", possibly the first conception of angular momentum as we now understand it. + +In 1799, Pierre-Simon Laplace first realized that a fixed plane was associated with rotation—his invariable plane. + +Louis Poinsot in 1803 began representing rotations as a line segment perpendicular to the rotation, and elaborated on the "conservation of moments". + +In 1852 Léon Foucault used a gyroscope in an experiment to display the Earth's rotation. + +William J. M. Rankine's 1858 Manual of Applied Mechanics defined angular momentum in the modern sense for the first time:...a line whose length is proportional to the magnitude of the angular momentum, and whose direction is perpendicular to the plane of motion of the body and of the fixed point, and such, that when the motion of the body is viewed from the extremity of the line, the radius-vector of the body seems to have right-handed rotation.In an 1872 edition of the same book, Rankine stated that "The term angular momentum was introduced by Mr. Hayward," probably referring to R.B. Hayward's article On a Direct Method of estimating Velocities, Accelerations, and all similar Quantities with respect to Axes moveable in any manner in Space with Applications, which was introduced in 1856, and published in 1864. Rankine was mistaken, as numerous publications feature the term starting in the late 18th to early 19th centuries. However, Hayward's article apparently was the first use of the term and the concept seen by much of the English-speaking world. Before this, angular momentum was typically referred to as "momentum of rotation" in English. + +See also + +Footnotes + +References + +Further reading + + + + . + +External links + + "What Do a Submarine, a Rocket and a Football Have in Common? Why the prolate spheroid is the shape for success" (Scientific American, November 8, 2010) + Conservation of Angular Momentum – a chapter from an online textbook + Angular Momentum in a Collision Process – derivation of the three-dimensional case + Angular Momentum and Rolling Motion – more momentum theory + +Mechanical quantities +Rotation +Conservation laws +Moment (physics) +Angular momentum +The plum pudding model is one of several historical scientific models of the atom. First proposed by J. J. Thomson in 1904 soon after the discovery of the electron, but before the discovery of the atomic nucleus, the model tried to account for two properties of atoms then known: that electrons are negatively charged subatomic particles and that atoms have no net electric charge. The plum pudding model has electrons surrounded by a volume of positive charge, like negatively charged "plums" embedded in a positively charged "pudding". + +Overview +It had been known for many years that atoms contain negatively charged subatomic particles. Thomson called them "corpuscles" (particles), but they were more commonly called "electrons", the name G. J. Stoney had coined for the "fundamental unit quantity of electricity" in 1891. It had also been known for many years that atoms have no net electric charge. Thomson held that atoms must also contain some positive charge that cancels out the negative charge of their electrons. Thomson published his proposed model in the March 1904 edition of the Philosophical Magazine, the leading British science journal of the day. In Thomson's view: +... the atoms of the elements consist of a number of negatively electrified corpuscles enclosed in a sphere of uniform positive electrification, ... + +Thomson's model was the first to assign a specific inner structure to an atom, though his original description did not include mathematical formulas. He had followed the work of William Thomson who had written a paper proposing a vortex atom in 1867, J.J. Thomson abandoned his 1890 "nebular atom" hypothesis, based on the vortex theory of the atom, in which atoms were composed of immaterial vortices and suggested there were similarities between the arrangement of vortices and periodic regularity found among the chemical elements. Thomson based his atomic model on known experimental evidence of the day, and in fact, followed Lord Kelvin's lead again as Kelvin had proposed a positive sphere atom a year earlier. Thomson's proposal, based on Kelvin's model of a positive volume charge, served to guide future experiments. + +The main objective of Thomson's model after its initial publication was to account for the electrically neutral and chemically varied state of the atom. Electron orbits were stable under classical mechanics. When an electron moves away from the center of the positively charged sphere it is subjected to a greater net positive inward force due to the presence of more positive charge inside its orbit (see Gauss's law). Electrons were free to rotate in rings that were further stabilized by interactions among the electrons, and spectroscopic measurements were meant to account for energy differences associated with different electron rings. As for the properties of matter, Thomson believed they arose from electrical effects. He further emphasized the need of a theory to help picture the physical and chemical aspects of an atom using the theory of corpuscles and positive charge. Thomson attempted unsuccessfully to reshape his model to account for some of the major spectral lines experimentally known for several elements. After the scientific discovery of radioactivity, Thomson decided to address it in his model by stating: +... we must face the problem of the constitution of the atom, and see if we can imagine a model which has in it the potentiality of explaining the remarkable properties shown by radio-active substances ... + +Thomson's model changed over the course of its initial publication, finally becoming a model with much more mobility containing electrons revolving in the dense field of positive charge rather than a static structure. Despite this, the colloquial nickname "plum pudding" was soon attributed to Thomson's model as the distribution of electrons within its positively charged region of space reminded many scientists of raisins, then called "plums", in the common English dessert, plum pudding. + +In 1909, Hans Geiger and Ernest Marsden conducted experiments where alpha particles were fired through thin sheets of gold. Their professor, Ernest Rutherford, expected to find results consistent with Thomson's atomic model. However, when the results were published in 1911, they instead implied the presence of a very small nucleus of positive charge at the center of each gold atom. This led to the development of the Rutherford model of the atom. Immediately after Rutherford published his results, Antonius van den Broek made the intuitive proposal that the atomic number of an atom is the total number of units of charge present in its nucleus. Henry Moseley's 1913 experiments (see Moseley's law) provided the necessary evidence to support Van den Broek's proposal. The effective nuclear charge was found to be consistent with the atomic number (Moseley found only one unit of charge difference). This work culminated in the solar-system-like Bohr model of the atom in the same year, in which a nucleus containing an atomic number of positive charges is surrounded by an equal number of electrons in orbital shells. As Thomson's model guided Rutherford's experiments, Bohr's model guided Moseley's research. The Bohr model was elaborated upon during the time of the "old quantum theory", and then subsumed by the full-fledged development of quantum mechanics. + +Related scientific problems +As an important example of a scientific model, the plum pudding model has motivated and guided several related scientific problems. + +Mathematical Thomson problem +A particularly useful mathematics problem related to the plum pudding model is the optimal distribution of equal point charges on a unit sphere, called the Thomson problem. The Thomson problem is a natural consequence of the plum pudding model in the absence of its uniform positive background charge. + +References + +Foundational quantum physics +Atoms +Electron +Periodic table +Obsolete theories in physics +Atomic theory is the scientific theory that matter is composed of particles called atoms. The concept that matter is composed of discrete particles is an ancient idea, but gained scientific credence in the 18th and 19th centuries when scientists found it could explain the behaviors of gases and how chemical elements reacted with each other. By the end of the 19th century, atomic theory had gained widespread acceptance in the scientific community. + +The term "atom" comes from the Greek word atomos, which means "uncuttable". John Dalton applied the term to the basic units of mass of the chemical elements under the mistaken belief that chemical atoms are the fundamental particles in nature; it was another century before scientists realized that Dalton's so-called atoms have an underlying structure of their own. Particles which are truly indivisible are now referred to as "elementary particles". + +History + +Philosophical atomism + +The idea that matter is made up of discrete units is a very old idea, appearing in many ancient cultures, including Greece and India. The word "atom" (; ), meaning "uncuttable", was coined by the Pre-Socratic Greek philosophers Leucippus and his pupil Democritus (460–370 BC). Democritus taught that atoms were infinite in number, uncreated, and eternal, and that the qualities of an object result from the kind of atoms that compose it. Democritus's atomism was refined and elaborated by the later Greek philosopher Epicurus (341–270 BC), and by the Roman Epicurean poet Lucretius (99–55 BC). During the Early Middle Ages, atomism was mostly forgotten in western Europe. During the 12th century, it became known again in western Europe through references to it in the newly-rediscovered writings of Aristotle. The opposing view of matter upheld by Aristotle was that matter was continuous and infinite and could be subdivided without limit. + +In the 14th century, the rediscovery of major ancient works describing atomist teachings, including Lucretius's De rerum natura and Diogenes Laërtius's Lives and Opinions of Eminent Philosophers, led to increased scholarly attention on the subject. Nonetheless, because atomism was associated with the philosophy of Epicureanism, which contradicted orthodox Christian teachings, belief in atoms was not considered acceptable by most European philosophers. The French Catholic priest Pierre Gassendi (1592–1655) revived Epicurean atomism with modifications, arguing that atoms were created by God and, though extremely numerous, are not infinite in number. He was the first person who used the term "molecule" to describe aggregation of atoms. Gassendi's modified theory of atoms was popularized in France by the physician François Bernier (1620–1688) and in England by the natural philosopher Walter Charleton (1619–1707). The chemist Robert Boyle (1627–1691) and the physicist Isaac Newton (1642–1727) both defended atomism and, by the end of the 17th century, the idea of an atomistic foundation of nature had become accepted by portions of the scientific community. + +Dalton's law of multiple proportions + +Near the end of the 18th century, two laws about chemical reactions emerged without referring to the notion of an atomic theory. The first was the law of conservation of mass, closely associated with the work of Antoine Lavoisier, which states that the total mass in a chemical reaction remains constant (that is, the reactants have the same mass as the products). The second was the law of definite proportions. First established by the French chemist Joseph Proust in 1797 this law states that if a compound is broken down into its constituent chemical elements, then the masses of the constituents will always have the same proportions by weight, regardless of the quantity or source of the original substance. + +John Dalton studied data gathered by himself and other scientists and noticed a pattern that later came to be known as the law of multiple proportions. In compounds which all contain a particular element, the content of that element will differ across these compounds by ratios of small whole numbers. Dalton concluded from all this that elements react with each other in discrete and consistent units of weight. Borrowing the word from the philosophical tradition, Dalton called these units atoms. + +Example 1 — tin oxides: Dalton identified two oxides of tin. One is a grey powder (which Dalton referred to as the "protoxide") in which for every 100 parts of tin there is 13.5 parts of oxygen. The other oxide is a white powder (which Dalton referred to as the "deutoxide") in which for every 100 parts of tin there are 27 parts of oxygen. 13.5 and 27 form a ratio of 1:2. Dalton concluded that in the grey oxide, there is one oxygen atom for every tin atom, and in the white oxide there are two oxygen atoms for every tin atom. These oxides are today known as tin(II) oxide (SnO) and tin(IV) oxide (SnO2) respectively. + +Example 2 — iron oxides: Dalton identified two oxides of iron. One is a black powder in which for every 100 parts of iron there are about 28 parts of oxygen. The other is a red powder in which for every 100 parts of iron there are 42 parts of oxygen. 28 and 42 form a ratio of 2:3. These oxides are today known as iron(II) oxide (better known as wüstite) and iron(III) oxide (the major constituent of rust). Their modern formulas are Fe2O2 and Fe2O3 respectively. + +Example 3 — nitrogen oxides: Dalton was aware of three oxides of nitrogen: "nitrous oxide", "nitrous gas", and "nitric acid" (these compounds are known today as nitrous oxide, nitric oxide, and nitrogen dioxide respectively). Dalton understood that "Nitrous oxide" is 63.3% nitrogen and 36.7% oxygen, which means it has 80 g of oxygen for every 140 g of nitrogen. "Nitrous gas" is 44.05% nitrogen and 55.95% oxygen, which means there are 160 g of oxygen for every 140 g of nitrogen. "Nitric acid" is 29.5% nitrogen and 70.5% oxygen, which means it has 320 g of oxygen for every 140 g of nitrogen. 80 g, 160 g, and 320 g form a ratio of 1:2:4. Dalton's formulas for these compounds were N2O, NO, and NO2, essentially the same as today's. + +Dalton's atomic theory +From the evidence provided by the law of multiple proportions Dalton developed his atomic theory. A central problem for the theory was to determine the relative weights of the atoms of various elements. The atomic weight of an element is the weight an atom of that element is compared to the weights of atoms of the other elements. Dalton and his contemporaries could not measure the absolute weight of atoms—i.e. their weight in grams—because atoms were far too small to be directly measured with the technologies that existed in the 19th century. Instead, they measured how heavy atoms of various elements were relative to atoms of hydrogen, which chemists of Dalton's day knew was the lightest element in nature. + +Dalton estimated the atomic weights according to the mass ratios in which they combined, with the weight of the hydrogen atom taken conventionally as unity. However, Dalton did not realize that some elements exist as molecules in their natural pure form—-e.g. pure oxygen exists as O2. He also mistakenly believed that the simplest compound between any two elements is always one atom of each (so he thought water was HO, not H2O). This, in addition to the limitations of his apparatus, flawed his results. For instance, in 1803 he believed that oxygen atoms were 5.5 times heavier than hydrogen atoms, because in water he measured 5.5 grams of oxygen for every 1 gram of hydrogen and believed the formula for water was HO. Adopting better data, in 1806 he concluded that the atomic weight of oxygen must actually be 7 rather than 5.5, and he retained this weight for the rest of his life. Others at this time had already concluded from more precise measurements that the oxygen atom must weigh 8 relative to hydrogen equals 1, if one assumes Dalton's formula for the water molecule (HO), or 16 if one assumes the modern water formula (H2O). + +The flaw in Dalton's theory was corrected in principle in 1811 by Amedeo Avogadro. Avogadro had proposed that equal volumes of any two gases, at equal temperature and pressure, contain equal numbers of molecules (in other words, the mass of a gas's particles does not affect the volume that it occupies). Avogadro's hypothesis, now usually called Avogadro's law, provided a method for deducing the relative weights of the molecules of gaseous elements, for if the hypothesis is correct relative gas densities directly indicate the relative weights of the particles that compose the gases. This way of thinking led directly to a second hypothesis: the particles of certain elemental gases were not atoms, but molecules consisting of two atoms each; and when combining chemically these molecules often split in two. For instance, the fact that two liters of hydrogen will react with just one liter of oxygen to produce two liters of water vapor (at constant pressure and temperature) suggested that a single oxygen molecule must split in two in order to form two molecules of water. This also meant that the water molecule must be H2O. Thus, Avogadro was able to offer more accurate estimates of the atomic mass of oxygen and various other elements, and made a distinction between molecules and atoms. What we now call atoms Avogadro called "elementary molecules", and what we now call molecules Avogadro called "compound molecules". + +Opposition to atomic theory +Dalton's atomic theory was not immediately accepted by all scientists. + +One problem was the lack of uniform nomenclature. The word "atom" implied indivisibility, but Dalton instead defined an atom as being the basic particle of any substance, which meant that "compound atoms" such as carbon dioxide could divided, as opposed to "elementary atoms". Other scientists used their own nomenclature, which only added to the general confusion. For instance, J. J. Berzelius used the term "organic atoms" to refer to particles containing three or more elements, because he thought this only existed in organic compounds. + +A second problem was philosophical. Scientists in the 19th century had no way of directly observing atoms. They inferred the existence of atoms through indirect observations, such as Dalton's law of multiple proportions. Some Scientists, notably those who ascribed to the school of positivism, argued that scientists should not attempt to deduce the deeper reality of the universe, but only systemize what patterns they can directly observe. The anti-atomists argued that while atoms might be a useful abstraction for predicting how elements react, they do not reflect concrete reality. + +Such scientists were sometimes known as "equivalentists", because they preferred the theory of equivalent weights, which is a generalization of Proust's law of definite proportions. For example, 1 gram of hydrogen will combine with 8 grams of oxygen to form 9 grams of water, therefore the equivalent weight of oxygen is 8 grams. This position was eventually quashed by two important advancements that happened later in the 19th century: the development of the periodic table and the discovery that molecules have an internal architecture that determines their properties. + +Dalton's law of multiple proportions was also shown to not be a universal law when it came to organic substances. For instance, in oleic acid there is 34 g of hydrogen for every 216 g of carbon, and in methane there is 72 g of hydrogen for every 216 g of carbon. 34 and 72 form a ratio of 17:36, which is not a ratio of small whole numbers. We know now that carbon-based substances can have very large molecules, larger than any the other elements can form. Oleic acid's formula is C18H34O2 and methane's is CH4. + +Isomerism +Scientists soon discovered cases of substances that have the same proportional elemental composition but different properties. For instance, in 1827, Friedrich Wöhler discovered that silver fulminate and silver cyanate are both 107 parts silver, 12 parts carbon, 14 parts nitrogen, and 12 parts oxygen (we now know their formulas as both AgCNO). Wöhler also discovered that urea and ammonium cyanate both have the same composition (we now know their formulas are CH4N2O) but different properties. In 1830, Jöns Jacob Berzelius introduced the term isomerism to describe the phenomenon. Most chemists of the 1830s and later accepted the suggestion that isomerism resulted from the differing arrangements of the same numbers and types of atoms, resulting in distinct substances. The numbers of isomers proliferated rapidly with the development of organic chemistry, especially after the introduction of atomic valence and structural theory in the 1860s. Consider, for example, pentane (C5H12). According to the theories of valence and structure, there are three possible atomic configurations for the pentane molecule, and there really are three different substances that have the same composition as pentane but different properties. + +Isomerism was not something that could be fully explained by alternative theories to atomic theory, such as radical theory and the theory of types. + +In 1860, Louis Pasteur hypothesized that the molecules of isomers might have the same composition but different arrangements of their atoms in three dimensions. In 1874, Jacobus Henricus van 't Hoff proposed that the carbon atom forms bonds to other atoms in a tetrahedral arrangement. Working from this hypothesis, he could explain cases of isomerism where the relevant molecules appeared to have the same basic skeletal structure; the two molecules differed only in their three-dimensional spatial configurations, like two otherwise identical left and right hands, or two identical spirals that wind clockwise and counterclockwise. + +Mendeleev's periodic table + +Dmitrii Mendeleev noticed that when he arranged the elements in a row according to their atomic weights, there was a certain periodicity to them. For instance, the second element, lithium, had similar properties to the ninth element, sodium, and the sixteenth element, potassium — a period of seven. Likewise, beryllium, magnesium, and calcium were similar and all were seven places apart from each other on Mendeleev's table (eight places apart on the modern table). Using these patterns, Mendeleev predicted the existence and properties of new elements, which were later discovered in nature: scandium, gallium, and germanium. Moreover, the periodic table could predict how many atoms of other elements that an atom could bond with — e.g., germanium and carbon are in the same group on the table and their atoms both combine with two oxygen atoms each (GeO2 and CO2). Mendeleev found these patterns to confirm the hypothesis that matter is made of atoms because it showed that the elements could be categorized by their atomic weight. Inserting a new element into the middle of a period would break the parallel between that period and the next, and would also violate Dalton's law of multiple proportions. + +Brownian motion +In 1827, the British botanist Robert Brown observed that dust particles inside pollen grains floating in water constantly jiggled about for no apparent reason. In 1905, Albert Einstein theorized that this Brownian motion was caused by the water molecules continuously knocking the grains about, and developed a mathematical model to describe it. This model was validated experimentally in 1908 by French physicist Jean Perrin, who used Einstein's equations to determine the size of atoms. + +Statistical mechanics +In order to introduce the Ideal gas law and statistical forms of physics, it was necessary to postulate the existence of atoms. In 1738, Swiss physicist and mathematician Daniel Bernoulli postulated that the pressure of gases and heat were both caused by the underlying motion of molecules. + +In 1860, James Clerk Maxwell, who was a vocal proponent of atomism, was the first to use statistical mechanics in physics. Ludwig Boltzmann and Rudolf Clausius expanded his work on gases and the laws of Thermodynamics especially the second law relating to entropy. In the 1870s, Josiah Willard Gibbs extended the laws of entropy and thermodynamics and coined the term "statistical mechanics." Einstein later independently reinvented Gibbs' laws, because they had only been printed in an obscure American journal. Einstein later commented that had he known of Gibbs' work, he would "not have published those papers at all, but confined myself to the treatment of some few points [that were distinct]." All of statistical mechanics and the laws of heat, gas, and entropy took the existence of atoms as a necessary postulate. + +Discovery of subatomic particles + +Atoms were thought to be the smallest possible division of matter until 1897 when J. J. Thomson discovered the electron through his work on cathode rays. + +A Crookes tube is a sealed glass container in which two electrodes are separated by a vacuum. When a voltage is applied across the electrodes, cathode rays are generated, creating a glowing patch where they strike the glass at the opposite end of the tube. Through experimentation, Thomson discovered that the rays could be deflected by an electric field (in addition to magnetic fields, which was already known). He concluded that these rays, rather than being a form of light, were composed of very light negatively charged particles. Thomson called these "corpuscles", but other scientists called them electrons, following an 1894 suggestion by George Johnstone Stoney for naming the basic unit of electrical charge. He measured the mass-to-charge ratio and discovered it was 1800 times smaller than that of hydrogen, the smallest atom. These corpuscles were a particle unlike any other previously known. + +Thomson suggested that atoms were divisible, and that the corpuscles were their building blocks. To explain the overall neutral charge of the atom, he proposed that the corpuscles were distributed in a uniform sea of positive charge. This became known as the plum pudding model as the electrons were embedded in the positive charge like bits of fruit in a dried-fruit pudding, though Thomson thought the electrons moved about within the atom. + +Discovery of the nucleus + +Thomson's plum pudding model was disproved in 1909 by one of his former students, Ernest Rutherford, who discovered that most of the mass and positive charge of an atom is concentrated in a very small fraction of its volume, which he assumed to be at the very center. + +Ernest Rutherford and his colleagues Hans Geiger and Ernest Marsden came to have doubts about the Thomson model after they encountered difficulties when they tried to build an instrument to measure the charge-to-mass ratio of alpha particles (these are positively-charged particles emitted by certain radioactive substances such as radium). The alpha particles were being scattered by the air in the detection chamber, which made the measurements unreliable. Thomson had encountered a similar problem in his work on cathode rays, which he solved by creating a near-perfect vacuum in his instruments. Rutherford didn't think he'd run into this same problem because alpha particles are much heavier than electrons. According to Thomson's model of the atom, the positive charge in the atom is not concentrated enough to produce an electric field strong enough to deflect an alpha particle, and the electrons are so lightweight they should be pushed aside effortlessly by the much heavier alpha particles. Yet there was scattering, so Rutherford and his colleagues decided to investigate this scattering carefully. + +Between 1908 and 1913, Rutherford and his colleagues performed a series of experiments in which they bombarded thin foils of metal with alpha particles. They spotted alpha particles being deflected by angles greater than 90°. To explain this, Rutherford proposed that the positive charge of the atom is not distributed throughout the atom's volume as Thomson believed, but is concentrated in a tiny nucleus at the center. Only such an intense concentration of charge could produce an electric field strong enough to deflect the alpha particles as observed. Rutherford's model is sometimes called the "planetary model". However, Hantaro Nagaoka was quoted by Rutherford as the first to suggest a planetary atom in 1904. And planetary models had been suggested as early as 1897 such as the one by Joseph Larmor. Probably the earliest solar system model was found in an unpublished note by Ludwig August Colding in 1854 whose idea was that atoms were analogous to planetary systems that rotate and cause magnetic polarity. + +First steps toward a quantum physical model of the atom + +The planetary model of the atom had two significant shortcomings. The first is that, unlike planets orbiting a sun, electrons are charged particles. An accelerating electric charge is known to emit electromagnetic waves according to the Larmor formula in classical electromagnetism. An orbiting charge should steadily lose energy and spiral toward the nucleus, colliding with it in a small fraction of a second. The second problem was that the planetary model could not explain the highly peaked emission and absorption spectra of atoms that were observed. + + +Quantum theory revolutionized physics at the beginning of the 20th century, when Max Planck and Albert Einstein postulated that light energy is emitted or absorbed in discrete amounts known as quanta (singular, quantum). This led to a series of quantum atomic models such as the quantum model of Arthur Erich Haas in 1910 and the 1912 John William Nicholson quantum atomic model that quantized angular momentum as h/2. In 1913, Niels Bohr incorporated this idea into his Bohr model of the atom, in which an electron could only orbit the nucleus in particular circular orbits with fixed angular momentum and energy, its distance from the nucleus (i.e., their radii) being proportional to its energy. Under this model an electron could not spiral into the nucleus because it could not lose energy in a continuous manner; instead, it could only make instantaneous "quantum leaps" between the fixed energy levels. When this occurred, light was emitted or absorbed at a frequency proportional to the change in energy (hence the absorption and emission of light in discrete spectra). + +Bohr's model was not perfect. It could only predict the spectral lines of hydrogen, not those of multielectron atoms. Worse still, it could not even account for all features of the hydrogen spectrum: as spectrographic technology improved, it was discovered that applying a magnetic field caused spectral lines to multiply in a way that Bohr's model couldn't explain. In 1916, Arnold Sommerfeld added elliptical orbits to the Bohr model to explain the extra emission lines, but this made the model very difficult to use, and it still couldn't explain more complex atoms. + +Discovery of isotopes + +While experimenting with the products of radioactive decay, in 1913 radiochemist Frederick Soddy discovered that there appeared to be more than one variety of some elements. The term isotope was coined by Margaret Todd as a suitable name for these varieties. + +That same year, J. J. Thomson conducted an experiment in which he channeled a stream of neon ions through magnetic and electric fields, striking a photographic plate at the other end. He observed two glowing patches on the plate, which suggested two different deflection trajectories. Thomson concluded this was because some of the neon ions had a different mass. The nature of this differing mass would later be explained by the discovery of neutrons in 1932: all atoms of the same element contain the same number of protons, while different isotopes have different numbers of neutrons. + +Discovery of nuclear particles + +In 1917 Rutherford bombarded nitrogen gas with alpha particles and observed hydrogen nuclei being emitted from the gas (Rutherford recognized these, because he had previously obtained them bombarding hydrogen with alpha particles, and observing hydrogen nuclei in the products). Rutherford concluded that the hydrogen nuclei emerged from the nuclei of the nitrogen atoms themselves (in effect, he had split a nitrogen). + +From his own work and the work of his students Bohr and Henry Moseley, Rutherford knew that the positive charge of any atom could always be equated to that of an integer number of hydrogen nuclei. This, coupled with the atomic mass of many elements being roughly equivalent to an integer number of hydrogen atoms - then assumed to be the lightest particles - led him to conclude that hydrogen nuclei were singular particles and a basic constituent of all atomic nuclei. He named such particles protons. Further experimentation by Rutherford found that the nuclear mass of most atoms exceeded that of the protons it possessed; he speculated that this surplus mass was composed of previously-unknown neutrally charged particles, which were tentatively dubbed "neutrons". + +In 1928, Walter Bothe observed that beryllium emitted a highly penetrating, electrically neutral radiation when bombarded with alpha particles. It was later discovered that this radiation could knock hydrogen atoms out of paraffin wax. Initially it was thought to be high-energy gamma radiation, since gamma radiation had a similar effect on electrons in metals, but James Chadwick found that the ionization effect was too strong for it to be due to electromagnetic radiation, so long as energy and momentum were conserved in the interaction. In 1932, Chadwick exposed various elements, such as hydrogen and nitrogen, to the mysterious "beryllium radiation", and by measuring the energies of the recoiling charged particles, he deduced that the radiation was actually composed of electrically neutral particles which could not be massless like the gamma ray, but instead were required to have a mass similar to that of a proton. Chadwick now claimed these particles as Rutherford's neutrons. For his discovery of the neutron, Chadwick received the Nobel Prize in 1935. + +Quantum physical models of the atom + +In 1924, Louis de Broglie proposed that all moving particles—particularly subatomic particles such as electrons—exhibit a degree of wave-like behavior. Erwin Schrödinger, fascinated by this idea, explored whether or not the movement of an electron in an atom could be better explained as a wave rather than as a particle. Schrödinger's equation, published in 1926, describes an electron as a wave function instead of as a point particle. This approach elegantly predicted many of the spectral phenomena that Bohr's model failed to explain. Although this concept was mathematically convenient, it was difficult to visualize, and faced opposition. One of its critics, Max Born, proposed instead that Schrödinger's wave function did not describe the physical extent of an electron (like a charge distribution in classical electromagnetism), but rather gave the probability that an electron would, when measured, be found at a particular point. This reconciled the ideas of wave-like and particle-like electrons: the behavior of an electron, or of any other subatomic entity, has both wave-like and particle-like aspects, and whether one aspect or the other is more apparent depends upon the situation. + +A consequence of describing electrons as waveforms is that it is mathematically impossible to simultaneously derive the position and momentum of an electron. This became known as the Heisenberg uncertainty principle after the theoretical physicist Werner Heisenberg, who first published a version of it in 1927. (Heisenberg analyzed a thought experiment where one attempts to measure an electron's position and momentum simultaneously. However, Heisenberg did not give precise mathematical definitions of what the "uncertainty" in these measurements meant. The precise mathematical statement of the position-momentum uncertainty principle is due to Earle Hesse Kennard, Wolfgang Pauli, and Hermann Weyl.) This invalidated Bohr's model, with its neat, clearly defined circular orbits. The modern model of the atom describes the positions of electrons in an atom in terms of probabilities. An electron can potentially be found at any distance from the nucleus, but, depending on its energy level and angular momentum, exists more frequently in certain regions around the nucleus than others; this pattern is referred to as its atomic orbital. The orbitals come in a variety of shapes—sphere, dumbbell, torus, etc.—with the nucleus in the middle. The shapes of atomic orbitals are found by solving the Schrödinger equation; however, analytic solutions of the Schrödinger equation are known for very few relatively simple model Hamiltonians including the hydrogen atom and the dihydrogen cation. Even the helium atom—which contains just two electrons—has defied all attempts at a fully analytic treatment. + +See also + +Spectroscopy +History of molecular theory +Timeline of chemical element discoveries +Introduction to quantum mechanics +Kinetic theory of gases +Atomism +The Physical Principles of the Quantum Theory + +Footnotes + +Bibliography + +Further reading +Charles Adolphe Wurtz (1881) The Atomic Theory, D. Appleton and Company, New York. +Alan J. Rocke (1984) Chemical Atomism in the Nineteenth Century: From Dalton to Cannizzaro, Ohio State University Press, Columbus (open access full text at http://digital.case.edu/islandora/object/ksl%3Ax633gj985). + +External links + +Atomism by S. Mark Cohen. +Atomic Theory - detailed information on atomic theory with respect to electrons and electricity. +The Feynman Lectures on Physics Vol. I Ch. 1: Atoms in Motion + +Statistical mechanics +Chemistry theories +Foundational quantum physics +Amount of substance +AI is artificial intelligence, intellectual ability in machines and robots. + +Ai, AI or A.I. may also refer to: + +Animals + Ai (chimpanzee), an individual experimental subject in Japan + Ai (sloth) or the pale-throated sloth, northern Amazonian mammal species + +Arts, entertainment and media + +Works + Ai (album), a 2004 release by Seraphim + A.I. Artificial Intelligence, a 2001 American film + A.I. Rising, a 2018 Serbian film + AI: The Somnium Files, a 2019 video game + American Idol, televised singing contest + The American Interest, a bimonthly magazine (2005–2020) + I (2015 film), an Indian Tamil film (initial title: Ai) + +Other uses in arts and media + + A.i. (band), a Californian rock–electroclash group + All in (poker), wagering one's entire stake + Appreciation Index, a British measure of broadcast programme approval + The Art Institutes, a chain of American art schools + Non-player character, in gaming (colloquially, an AI) + +Business + + , a phrase in job titles + Appreciative inquiry, an organizational development method + All-inclusive, a full service at a vacation resort including meals and drinks + +Organizations and businesses + Accuracy International, a firearms manufacturer + Adventure International, a video game publisher + Air India, the flag carrier airline of India, based in Delhi + Alitalia, the former flag carrier airline of Italy + Astra International, an Indonesian automotive company + Alexis I. duPont High School, Delaware, U.S. + Amnesty International, a human rights organisation + Appraisal Institute, an association of real estate appraisers + The Art Institutes, a chain of art schools + +People + Ai (surname), a Chinese surname + Ai (given name), a given name and list of people and characters with the name + King Ai of Zhou (died 441 BC) + Emperor Ai of Han (27–1 BC) + Emperor Ai of Jin (341–365) + Emperor Ai of Tang (892–908) + Ai (poet) (1947–2010), American poet + Ai (singer) (born 1981), Japanese-American singer and songwriter + Allen Iverson (born 1975), American retired professional basketball player ("A.I.") + Andre Iguodala (born 1984), American professional basketball player ("A.I. 2.0") + +Places + +Areas + Anguilla, a Caribbean territory (by ISO 3166-1 code) + Appenzell Innerrhoden, a Swiss canton + +Cities + Ai (Canaan), Biblical city + +United States + Ai, Alabama + Ai, Georgia + Ai, North Carolina + Ai, Ohio + +Landforms + +Religion, philosophy and mythology + Ái, a Norse god + Ai (Canaan), Biblical city + Ai (), Sinic concepts of love from Confucianism and Buddhism + , colloquially , a Greek word for 'saint' + Ai Toyon, the Yakut god of light + +Science and technology + +Agricultural science + Active ingredient, part of a pesticide + Artificial insemination of livestock and pets, in animal breeding + +Air force and aviation + Airborne Internet, a proposed air-to-air data network + Airborne Interception radar, a Royal Air Force air-to-air system + Air interdiction, an aerial military capability + Attitude indicator, a flight instrument on aircraft + +The Internet + .ai, a top-level domain + +Medical conditions + Accommodative insufficiency of the eye + Amelogenesis imperfecta of teeth + Aortic insufficiency of the heart + +Medicines and healthcare + Active ingredient, part of a drug + Adequate intake, a Dietary Reference Intake nutritional parameter + Aromatase inhibitor, a class of breast-cancer drug + Articulation Index, a method of measuring hearing loss + Artificial insemination, a method of fertilisation + Automated immunoassay, automated clinical analyses of blood + +Visual arts technologies + Adobe Illustrator, a vector graphics editor + .ai, Adobe Illustrator Artwork filename extension + Automatic Maximum-Aperture Indexing, aperture coupling on Nikon camera lenses + +See also + Artificial intelligence (disambiguation) + Art Institute (disambiguation) + All In (disambiguation) + A1 (disambiguation) + AL (disambiguation) + AY (disambiguation) + Aye (disambiguation) + Eye (disambiguation) +Aung San Suu Kyi (; ; born 19 June 1945), sometimes abbreviated to Suu Kyi, is a Burmese politician, diplomat, author, and a 1991 Nobel Peace Prize laureate who served as State Counsellor of Myanmar (equivalent to a prime minister) and Minister of Foreign Affairs from 2016 to 2021. She has served as the general secretary of the National League for Democracy (NLD) since the party's founding in 1988, and was registered as its chairperson while it was a legal party from 2011 to 2023. She played a vital role in Myanmar's transition from military junta to partial democracy in the 2010s. + +The youngest daughter of Aung San, Father of the Nation of modern-day Myanmar, and Khin Kyi, Aung San Suu Kyi was born in Rangoon, British Burma. After graduating from the University of Delhi in 1964 and +St Hugh's College, Oxford in 1968, she worked at the United Nations for three years. She married Michael Aris in 1972, with whom she had two children. + +Aung San Suu Kyi rose to prominence in the 8888 Uprising of 8 August 1988 and became the General Secretary of the NLD, which she had newly formed with the help of several retired army officials who criticized the military junta. In the 1990 elections, NLD won 81% of the seats in Parliament, but the results were nullified, as the military government (the State Peace and Development Council – SPDC) refused to hand over power, resulting in an international outcry. She had been detained before the elections and remained under house arrest for almost 15 of the 21 years from 1989 to 2010, becoming one of the world's most prominent political prisoners. In 1999, Time magazine named her one of the "Children of Gandhi" and his spiritual heir to nonviolence. She survived an assassination attempt in the 2003 Depayin massacre when at least 70 people associated with the NLD were killed. + +Her party boycotted the 2010 elections, resulting in a decisive victory for the military-backed Union Solidarity and Development Party (USDP). Aung San Suu Kyi became a Pyithu Hluttaw MP while her party won 43 of the 45 vacant seats in the 2012 by-elections. In the 2015 elections, her party won a landslide victory, taking 86% of the seats in the Assembly of the Union—well more than the 67% supermajority needed to ensure that its preferred candidates were elected president and second vice president in the presidential electoral college. Although she was prohibited from becoming the president due to a clause in the constitution—her late husband and children are foreign citizens—she assumed the newly created role of State Counsellor of Myanmar, a role akin to a prime minister or a head of government. + +When she ascended to the office of state counsellor, Aung San Suu Kyi drew criticism from several countries, organisations and figures over Myanmar's inaction in response to the genocide of the Rohingya people in Rakhine State and refusal to acknowledge that Myanmar's military has committed massacres. Under her leadership, Myanmar also drew criticism for prosecutions of journalists. In 2019, Aung San Suu Kyi appeared in the International Court of Justice where she defended the Burmese military against allegations of genocide against the Rohingya. + +Aung San Suu Kyi, whose party had won the November 2020 Myanmar general election, was arrested on 1 February 2021 following a coup d'état that returned the Tatmadaw (Myanmar Armed Forces) to power and sparked protests across the country. Several charges were filed against her, and on 6 December 2021, she was sentenced to four years in prison on two of them. Later, on 10 January 2022, she was sentenced to an additional four years on another set of charges. On 12 October 2022, she was convicted of two further charges of corruption and she was sentenced to two terms of three years' imprisonment to be served concurrent to each other. On 30 December 2022, her trials ended with another conviction and an additional sentence of seven years' imprisonment for corruption. Aung San Suu Kyi's final sentence was of 33 years in prison, later reduced to 27 years. The United Nations, most European countries, and the United States condemned the arrests, trials, and sentences as politically motivated. + +Name +Aung San Suu Kyi, like other Burmese names, includes no surname, but is only a personal name, in her case derived from three relatives: "Aung San" from her father, "Suu" from her paternal grandmother, and "Kyi" from her mother Khin Kyi. + +In Myanmar, Aung San Suu Kyi is often referred to as Daw Aung San Suu Kyi. Daw, literally meaning "aunt", is not part of her name but is an honorific for any older and revered woman, akin to "Madam". She is sometimes addressed as Daw Suu or Amay Suu ("Mother Suu") by her supporters. + +Personal life +Aung San Suu Kyi was born on 19 June 1945 in Rangoon (now Yangon), British Burma. According to Peter Popham, she was born in a small village outside Rangoon called Hmway Saung. Her father, Aung San, allied with the Japanese during World War II. Aung San founded the modern Burmese army and negotiated Burma's independence from the United Kingdom in 1947; he was assassinated by his rivals in the same year. She is a niece of Thakin Than Tun who was the husband of Khin Khin Gyi, the elder sister of her mother Khin Kyi. + +She grew up with her mother, Khin Kyi, and two brothers, Aung San Lin and Aung San Oo, in Rangoon. Aung San Lin died at the age of eight when he drowned in an ornamental lake on the grounds of the house. Her elder brother emigrated to San Diego, California, becoming a United States citizen. After Aung San Lin's death, the family moved to a house by Inya Lake where Aung San Suu Kyi met people of various backgrounds, political views, and religions. She was educated in Methodist English High School (now Basic Education High School No. 1 Dagon) for much of her childhood in Burma, where she was noted as having a talent for learning languages. She speaks four languages: Burmese, English, French, and Japanese. She is a Theravada Buddhist. + +Aung San Suu Kyi's mother, Khin Kyi, gained prominence as a political figure in the newly formed Burmese government. She was appointed Burmese ambassador to India and Nepal in 1960, and Aung San Suu Kyi followed her there. She studied in the Convent of Jesus and Mary School in New Delhi, and graduated from Lady Shri Ram College, a constituent college of the University of Delhi in New Delhi, with a degree in politics in 1964. Suu Kyi continued her education at St Hugh's College, Oxford, obtaining a B.A. degree in Philosophy, Politics and Economics in 1967, graduating with a third-class degree that was promoted per tradition to an MA in 1968. After graduating, she lived in New York City with family friend Ma Than E, who was once a popular Burmese pop singer. She worked at the United Nations for three years, primarily on budget matters, writing daily to her future husband, Dr. Michael Aris. On 1 January 1972, Aung San Suu Kyi and Aris, a scholar of Tibetan culture and literature, living abroad in Bhutan, were married. The following year, she gave birth to their first son, Alexander Aris, in London; their second son, Kim, was born in 1977. Between 1985 and 1987, Aung San Suu Kyi was working toward a Master of Philosophy degree in Burmese literature as a research student at the School of Oriental and African Studies (SOAS), University of London. She was elected as an Honorary Fellow of St Hugh's in 1990. For two years, she was a Fellow at the Indian Institute of Advanced Studies (IIAS) in Shimla, India. She also worked for the government of the Union of Burma. + +In 1988, Aung San Suu Kyi returned to Burma to tend for her ailing mother. Aris' visit in Christmas 1995 was the last time that he and Aung San Suu Kyi met, as she remained in Burma and the Burmese dictatorship denied him any further entry visas. Aris was diagnosed with prostate cancer in 1997 which was later found to be terminal. Despite appeals from prominent figures and organizations, including the United States, UN Secretary-General Kofi Annan and Pope John Paul II, the Burmese government would not grant Aris a visa, saying that they did not have the facilities to care for him, and instead urged Aung San Suu Kyi to leave the country to visit him. She was at that time temporarily free from house arrest but was unwilling to depart, fearing that she would be refused re-entry if she left, as she did not trust the military junta's assurance that she could return. + +Aris died on his 53rd birthday on 27 March 1999. Since 1989, when his wife was first placed under house arrest, he had seen her only five times, the last of which was for Christmas in 1995. She was also separated from her children, who live in the United Kingdom, until 2011. + +On 2 May 2008, after Cyclone Nargis hit Burma, Aung San Suu Kyi's dilapidated lakeside bungalow lost its roof and electricity, while the cyclone also left entire villages in the Irrawaddy delta submerged. Plans to renovate and repair the house were announced in August 2009. Aung San Suu Kyi was released from house arrest on 13 November 2010. + +Political career + +Political beginning +Coincidentally, when Aung San Suu Kyi returned to Burma in 1988, the long-time military leader of Burma and head of the ruling party, General Ne Win, stepped down. Mass demonstrations for democracy followed that event on 8 August 1988 (8–8–88, a day seen as auspicious), which were violently suppressed in what came to be known as the 8888 Uprising. On 24 August 1988, she made her first public appearance at the Yangon General Hospital, addressing protestors from a podium. On 26 August, she addressed half a million people at a mass rally in front of the Shwedagon Pagoda in the capital, calling for a democratic government. However, in September 1988, a new military junta took power. + +Influenced by both Mahatma Gandhi's philosophy of non-violence and also by the Buddhist concepts, Aung San Suu Kyi entered politics to work for democratization, helped found the National League for Democracy on 27 September 1988, but was put under house arrest on 20 July 1989. She was offered freedom if she left the country, but she refused. Despite her philosophy of non-violence, a group of ex-military commanders and senior politicians who joined NLD during the crisis believed that she was too confrontational and left NLD. However, she retained enormous popularity and support among NLD youths with whom she spent most of her time. + +During the crisis, the previous democratically elected Prime Minister of Burma, U Nu, initiated to form an interim government and invited opposition leaders to join him. Indian Prime Minister Rajiv Gandhi had signaled his readiness to recognize the interim government. However, Aung San Suu Kyi categorically rejected U Nu's plan by saying "the future of the opposition would be decided by masses of the people". Ex-Brigadier General Aung Gyi, another influential politician at the time of the 8888 crisis and the first chairman in the history of the NLD, followed the suit and rejected the plan after Aung San Suu Kyi's refusal. Aung Gyi later accused several NLD members of being communists and resigned from the party. + +1990 general election and Nobel Peace Prize +In 1990, the military junta called a general election, in which the National League for Democracy (NLD) received 59% of the votes, guaranteeing NLD 80% of the parliament seats. Some claim that Aung San Suu Kyi would have assumed the office of Prime Minister. Instead, the results were nullified and the military refused to hand over power, resulting in an international outcry. Aung San Suu Kyi was placed under house arrest at her home on University Avenue () in Rangoon, during which time she was awarded the Sakharov Prize for Freedom of Thought in 1990, and the Nobel Peace Prize one year later. Her sons Alexander and Kim accepted the Nobel Peace Prize on her behalf. Aung San Suu Kyi used the Nobel Peace Prize's US$1.3 million prize money to establish a health and education trust for the Burmese people. Around this time, Aung San Suu Kyi chose nonviolence as an expedient political tactic, stating in 2007, "I do not hold to nonviolence for moral reasons, but for political and practical reasons." + +The decision of the Nobel Committee mentions: + +In 1995 Aung San Suu Kyi delivered the keynote address at the Fourth World Conference on Women in Beijing. + +1996 attack +On 9 November 1996, the motorcade that Aung San Suu Kyi was traveling in with other National League for Democracy leaders Tin Oo and Kyi Maung, was attacked in Yangon. About 200 men swooped down on the motorcade, wielding metal chains, metal batons, stones and other weapons. The car that Aung San Suu Kyi was in had its rear window smashed, and the car with Tin Oo and Kyi Maung had its rear window and two backdoor windows shattered. It is believed the offenders were members of the Union Solidarity and Development Association (USDA) who were allegedly paid Ks.500/- (@ USD $0.50) each to participate. The NLD lodged an official complaint with the police, and according to reports the government launched an investigation, but no action was taken. (Amnesty International 120297) + +House arrest +Aung San Suu Kyi was placed under house arrest for a total of 15 years over a 21-year period, on numerous occasions, since she began her political career, during which time she was prevented from meeting her party supporters and international visitors. In an interview, she said that while under house arrest she spent her time reading philosophy, politics and biographies that her husband had sent her. She also passed the time playing the piano and was occasionally allowed visits from foreign diplomats as well as from her personal physician. + +Although under house arrest, Aung San Suu Kyi was granted permission to leave Burma under the condition that she never return, which she refused: "As a mother, the greater sacrifice was giving up my sons, but I was always aware of the fact that others had given up more than me. I never forget that my colleagues who are in prison suffer not only physically, but mentally for their families who have no security outside – in the larger prison of Burma under authoritarian rule." + +The media were also prevented from visiting Aung San Suu Kyi, as occurred in 1998 when journalist Maurizio Giuliano, after photographing her, was stopped by customs officials who then confiscated all his films, tapes and some notes. In contrast, Aung San Suu Kyi did have visits from government representatives, such as during her autumn 1994 house arrest when she met the leader of Burma, General Than Shwe and General Khin Nyunt on 20 September in the first meeting since she had been placed in detention. On several occasions during her house arrest, she had periods of poor health and as a result was hospitalized. + +The Burmese government detained and kept Aung San Suu Kyi imprisoned because it viewed her as someone "likely to undermine the community peace and stability" of the country, and used both Article 10(a) and 10(b) of the 1975 State Protection Act (granting the government the power to imprison people for up to five years without a trial), and Section 22 of the "Law to Safeguard the State Against the Dangers of Those Desiring to Cause Subversive Acts" as legal tools against her. She continuously appealed her detention, and many nations and figures continued to call for her release and that of 2,100 other political prisoners in the country. On 12 November 2010, days after the junta-backed Union Solidarity and Development Party (USDP) won elections conducted after a gap of 20 years, the junta finally agreed to sign orders allowing Aung San Suu Kyi's release, and her house arrest term came to an end on 13 November 2010. + +United Nations involvement +The United Nations (UN) has attempted to facilitate dialogue between the junta and Aung San Suu Kyi. On 6 May 2002, following secret confidence-building negotiations led by the UN, the government released her; a government spokesman said that she was free to move "because we are confident that we can trust each other". Aung San Suu Kyi proclaimed "a new dawn for the country". However, on 30 May 2003 in an incident similar to the 1996 attack on her, a government-sponsored mob attacked her caravan in the northern village of Depayin, murdering and wounding many of her supporters. Aung San Suu Kyi fled the scene with the help of her driver, Kyaw Soe Lin, but was arrested upon reaching Ye-U. The government imprisoned her at Insein Prison in Rangoon. After she underwent a hysterectomy in September 2003, the government again placed her under house arrest in Rangoon. + +The results from the UN facilitation have been mixed; Razali Ismail, UN special envoy to Burma, met with Aung San Suu Kyi. Ismail resigned from his post the following year, partly because he was denied re-entry to Burma on several occasions. Several years later in 2006, Ibrahim Gambari, UN Undersecretary-General (USG) of Department of Political Affairs, met with Aung San Suu Kyi, the first visit by a foreign official since 2004. He also met with her later the same year. On 2 October 2007 Gambari returned to talk to her again after seeing Than Shwe and other members of the senior leadership in Naypyidaw. State television broadcast Aung San Suu Kyi with Gambari, stating that they had met twice. This was Aung San Suu Kyi's first appearance in state media in the four years since her current detention began. + +The United Nations Working Group for Arbitrary Detention published an Opinion that Aung San Suu Kyi's deprivation of liberty was arbitrary and in contravention of Article 9 of the Universal Declaration of Human Rights 1948, and requested that the authorities in Burma set her free, but the authorities ignored the request at that time. The U.N. report said that according to the Burmese Government's reply, "Daw Aung San Suu Kyi has not been arrested, but has only been taken into protective custody, for her own safety", and while "it could have instituted legal action against her under the country's domestic legislation ... it has preferred to adopt a magnanimous attitude, and is providing her with protection in her own interests". + +Such claims were rejected by Brig-General Khin Yi, Chief of Myanmar Police Force (MPF). On 18 January 2007, the state-run paper New Light of Myanmar accused Aung San Suu Kyi of tax evasion for spending her Nobel Prize money outside the country. The accusation followed the defeat of a US-sponsored United Nations Security Council resolution condemning Burma as a threat to international security; the resolution was defeated because of strong opposition from China, which has strong ties with the military junta (China later voted against the resolution, along with Russia and South Africa). + +In November 2007, it was reported that Aung San Suu Kyi would meet her political allies National League for Democracy along with a government minister. The ruling junta made the official announcement on state TV and radio just hours after UN special envoy Ibrahim Gambari ended his second visit to Burma. The NLD confirmed that it had received the invitation to hold talks with Aung San Suu Kyi. However, the process delivered few concrete results. + +On 3 July 2009, UN Secretary-General Ban Ki-moon went to Burma to pressure the junta into releasing Aung San Suu Kyi and to institute democratic reform. However, on departing from Burma, Ban Ki-moon said he was "disappointed" with the visit after junta leader Than Shwe refused permission for him to visit Aung San Suu Kyi, citing her ongoing trial. Ban said he was "deeply disappointed that they have missed a very important opportunity". + +Periods under detention + 20 July 1989: Placed under house arrest in Rangoon under martial law that allows for detention without charge or trial for three years. + 10 July 1995: Released from house arrest. + 23 September 2000: Placed under house arrest. + 6 May 2002: Released after 19 months. + 30 May 2003: Arrested following the Depayin massacre, she was held in secret detention for more than three months before being returned to house arrest. + 25 May 2007: House arrest extended by one year despite a direct appeal from U.N. Secretary-General Kofi Annan to General Than Shwe. + 24 October 2007: Reached 12 years under house arrest, solidarity protests held at 12 cities around the world. + 27 May 2008: House arrest extended for another year, which is illegal under both international law and Burma's own law. + 11 August 2009: House arrest extended for 18 more months because of "violation" arising from the May 2009 trespass incident. + 13 November 2010: Released from house arrest. + +2007 anti-government protests + +Protests led by Buddhist monks began on 19 August 2007 following steep fuel price increases, and continued each day, despite the threat of a crackdown by the military. + +On 22 September 2007, although still under house arrest, Aung San Suu Kyi made a brief public appearance at the gate of her residence in Yangon to accept the blessings of Buddhist monks who were marching in support of human rights. It was reported that she had been moved the following day to Insein Prison (where she had been detained in 2003), but meetings with UN envoy Ibrahim Gambari near her Rangoon home on 30 September and 2 October established that she remained under house arrest. + +2009 trespass incident + +On 3 May 2009, an American man, identified as John Yettaw, swam across Inya Lake to her house uninvited and was arrested when he made his return trip three days later. He had attempted to make a similar trip two years earlier, but for unknown reasons was turned away. He later claimed at trial that he was motivated by a divine vision requiring him to notify her of an impending terrorist assassination attempt. On 13 May, Aung San Suu Kyi was arrested for violating the terms of her house arrest because the swimmer, who pleaded exhaustion, was allowed to stay in her house for two days before he attempted the swim back. Aung San Suu Kyi was later taken to Insein Prison, where she could have faced up to five years' confinement for the intrusion. The trial of Aung San Suu Kyi and her two maids began on 18 May and a small number of protesters gathered outside. Diplomats and journalists were barred from attending the trial; however, on one occasion, several diplomats from Russia, Thailand and Singapore and journalists were allowed to meet Aung San Suu Kyi. The prosecution had originally planned to call 22 witnesses. It also accused John Yettaw of embarrassing the country. During the ongoing defence case, Aung San Suu Kyi said she was innocent. The defence was allowed to call only one witness (out of four), while the prosecution was permitted to call 14 witnesses. The court rejected two character witnesses, NLD members Tin Oo and Win Tin, and permitted the defence to call only a legal expert. According to one unconfirmed report, the junta was planning to, once again, place her in detention, this time in a military base outside the city. In a separate trial, Yettaw said he swam to Aung San Suu Kyi's house to warn her that her life was "in danger". The national police chief later confirmed that Yettaw was the "main culprit" in the case filed against Aung San Suu Kyi. According to aides, Aung San Suu Kyi spent her 64th birthday in jail sharing biryani rice and chocolate cake with her guards. + +Her arrest and subsequent trial received worldwide condemnation by the UN Secretary General Ban Ki-moon, the United Nations Security Council, Western governments, South Africa, Japan and the Association of Southeast Asian Nations, of which Burma is a member. The Burmese government strongly condemned the statement, as it created an "unsound tradition" and criticised Thailand for meddling in its internal affairs. The Burmese Foreign Minister Nyan Win was quoted in the state-run newspaper New Light of Myanmar as saying that the incident "was trumped up to intensify international pressure on Burma by internal and external anti-government elements who do not wish to see the positive changes in those countries' policies toward Burma". Ban responded to an international campaign by flying to Burma to negotiate, but Than Shwe rejected all of his requests. + +On 11 August 2009, the trial concluded with Aung San Suu Kyi being sentenced to imprisonment for three years with hard labour. This sentence was commuted by the military rulers to further house arrest of 18 months. On 14 August, US Senator Jim Webb visited Burma, visiting with junta leader Gen. Than Shwe and later with Aung San Suu Kyi. During the visit, Webb negotiated Yettaw's release and deportation from Burma. Following the verdict of the trial, lawyers of Aung San Suu Kyi said they would appeal against the 18-month sentence. On 18 August, United States President Barack Obama asked the country's military leadership to set free all political prisoners, including Aung San Suu Kyi. In her appeal, Aung San Suu Kyi had argued that the conviction was unwarranted. However, her appeal against the August sentence was rejected by a Burmese court on 2 October 2009. Although the court accepted the argument that the 1974 constitution, under which she had been charged, was null and void, it also said the provisions of the 1975 security law, under which she has been kept under house arrest, remained in force. The verdict effectively meant that she would be unable to participate in the elections scheduled to take place in 2010—the first in Burma in two decades. Her lawyer stated that her legal team would pursue a new appeal within 60 days. + +Late 2000s: International support for release + +Aung San Suu Kyi has received vocal support from Western nations in Europe, Australia and North and South America, as well as India, Israel, Japan the Philippines and South Korea. In December 2007, the US House of Representatives voted unanimously 400–0 to award Aung San Suu Kyi the Congressional Gold Medal; the Senate concurred on 25 April 2008. On 6 May 2008, President George W. Bush signed legislation awarding Aung San Suu Kyi the Congressional Gold Medal. She is the first recipient in American history to receive the prize while imprisoned. More recently, there has been growing criticism of her detention by Burma's neighbours in the Association of Southeast Asian Nations, particularly from Indonesia, Thailand, the Philippines and Singapore. At one point Malaysia warned Burma that it faced expulsion from ASEAN as a result of the detention of Aung San Suu Kyi. Other nations including South Africa, Bangladesh and the Maldives also called for her release. The United Nations has urged the country to move towards inclusive national reconciliation, the restoration of democracy, and full respect for human rights. In December 2008, the United Nations General Assembly passed a resolution condemning the human rights situation in Burma and calling for Aung San Suu Kyi's release—80 countries voting for the resolution, 25 against and 45 abstentions. Other nations, such as China and Russia, are less critical of the regime and prefer to cooperate only on economic matters. Indonesia has urged China to push Burma for reforms. However, Samak Sundaravej, former Prime Minister of Thailand, criticised the amount of support for Aung San Suu Kyi, saying that "Europe uses Aung San Suu Kyi as a tool. If it's not related to Aung San Suu Kyi, you can have deeper discussions with Myanmar." + +Vietnam, however, did not support calls by other ASEAN member states for Myanmar to free Aung San Suu Kyi, state media reported Friday, 14 August 2009. The state-run Việt Nam News said Vietnam had no criticism of Myanmar's decision 11 August 2009 to place Aung San Suu Kyi under house arrest for the next 18 months, effectively barring her from elections scheduled for 2010. "It is our view that the Aung San Suu Kyi trial is an internal affair of Myanmar", Vietnamese government spokesman Le Dung stated on the website of the Ministry of Foreign Affairs. In contrast with other ASEAN member states, Dung said Vietnam has always supported Myanmar and hopes it will continue to implement the "roadmap to democracy" outlined by its government. + +Nobel Peace Prize winners (Archbishop Desmond Tutu, the Dalai Lama, Shirin Ebadi, Adolfo Pérez Esquivel, Mairead Corrigan, Rigoberta Menchú, Prof. Elie Wiesel, US President Barack Obama, Betty Williams, Jody Williams and former US President Jimmy Carter) called for the rulers of Burma to release Aung San Suu Kyi to "create the necessary conditions for a genuine dialogue with Daw Aung San Suu Kyi and all concerned parties and ethnic groups to achieve an inclusive national reconciliation with the direct support of the United Nations". Some of the money she received as part of the award helped fund higher education grants to Burmese students through the London-based charity Prospect Burma. + +It was announced prior to the 2010 Burmese general election that Aung San Suu Kyi may be released "so she can organize her party", However, Aung San Suu Kyi was not allowed to run. On 1 October 2010 the government announced that she would be released on 13 November 2010. + +US President Barack Obama personally advocated the release of all political prisoners, especially Aung San Suu Kyi, during the US-ASEAN Summit of 2009. + +The US Government hoped that successful general elections would be an optimistic indicator of the Burmese government's sincerity towards eventual democracy. The Hatoyama government which spent 2.82 billion yen in 2008, has promised more Japanese foreign aid to encourage Burma to release Aung San Suu Kyi in time for the elections; and to continue moving towards democracy and the rule of law. + +In a personal letter to Aung San Suu Kyi, UK Prime Minister Gordon Brown cautioned the Burmese government of the potential consequences of rigging elections as "condemning Burma to more years of diplomatic isolation and economic stagnation". + +Aung San Suu Kyi met with many heads of state and opened a dialog with the Minister of Labor Aung Kyi (not to be confused with Aung San Suu Kyi). She was allowed to meet with senior members of her NLD party at the State House, however these meetings took place under close supervision. + +2010 release + +On the evening of 13 November 2010, Aung San Suu Kyi was released from house arrest. This was the date her detention had been set to expire according to a court ruling in August 2009 and came six days after a widely criticised general election. She appeared in front of a crowd of her supporters, who rushed to her house in Rangoon when nearby barricades were removed by the security forces. Aung San Suu Kyi had been detained for 15 of the past 21 years. The government newspaper New Light of Myanmar reported the release positively, saying she had been granted a pardon after serving her sentence "in good conduct". The New York Times suggested that the military government may have released Aung San Suu Kyi because it felt it was in a confident position to control her supporters after the election. +Her son Kim Aris was granted a visa in November 2010 to see his mother shortly after her release, for the first time in 10 years. He visited again on 5 July 2011, to accompany her on a trip to Bagan, her first trip outside Yangon since 2003. Her son visited again on 8 August 2011, to accompany her on a trip to Pegu, her second trip. + +Discussions were held between Aung San Suu Kyi and the Burmese government during 2011, which led to a number of official gestures to meet her demands. In October, around a tenth of Burma's political prisoners were freed in an amnesty and trade unions were legalised. + +In November 2011, following a meeting of its leaders, the NLD announced its intention to re-register as a political party to contend 48 by-elections necessitated by the promotion of parliamentarians to ministerial rank. Following the decision, Aung San Suu Kyi held a telephone conference with US President Barack Obama, in which it was agreed that Secretary of State Hillary Clinton would make a visit to Burma, a move received with caution by Burma's ally China. On 1 December 2011, Aung San Suu Kyi met with Hillary Clinton at the residence of the top-ranking US diplomat in Yangon. + +On 21 December 2011, Thai Prime Minister Yingluck Shinawatra met Aung San Suu Kyi in Yangoon, marking Aung San Suu Kyi's "first-ever meeting with the leader of a foreign country". + +On 5 January 2012, British Foreign Minister William Hague met Aung San Suu Kyi and his Burmese counterpart. This represented a significant visit for Aung San Suu Kyi and Burma. Aung San Suu Kyi studied in the UK and maintains many ties there, whilst Britain is Burma's largest bilateral donor. +During Aung San Suu Kyi's visit to Europe, she visited the Swiss parliament, collected her 1991 Nobel Prize in Oslo and her honorary degree from the University of Oxford. + +2012 by-elections +In December 2011, there was speculation that Aung San Suu Kyi would run in the 2012 national by-elections to fill vacant seats. On 18 January 2012, Aung San Suu Kyi formally registered to contest a Pyithu Hluttaw (lower house) seat in the Kawhmu Township constituency in special parliamentary elections to be held on 1 April 2012. The seat was previously held by Soe Tint, who vacated it after being appointed Construction Deputy Minister, in the 2010 election. She ran against Union Solidarity and Development Party candidate Soe Min, a retired army physician and native of Twante Township. + +On 3 March 2012, at a large campaign rally in Mandalay, Aung San Suu Kyi unexpectedly left after 15 minutes, because of exhaustion and airsickness. + +In an official campaign speech broadcast on Burmese state television's MRTV on 14 March 2012, Aung San Suu Kyi publicly campaigned for reform of the 2008 Constitution, removal of restrictive laws, more adequate protections for people's democratic rights, and establishment of an independent judiciary. The speech was leaked online a day before it was broadcast. A paragraph in the speech, focusing on the Tatmadaw's repression by means of law, was censored by authorities. + +Aung San Suu Kyi also called for international media to monitor the by-elections, while publicly pointing out irregularities in official voter lists, which include deceased individuals and exclude other eligible voters in the contested constituencies. On 21 March 2012, Aung San Suu Kyi was quoted as saying "Fraud and rule violations are continuing and we can even say they are increasing." + +When asked whether she would assume a ministerial post if given the opportunity, she said the following: + +On 26 March 2012, Aung San Suu Kyi suspended her nationwide campaign tour early, after a campaign rally in Myeik (Mergui), a coastal town in the south, citing health problems due to exhaustion and hot weather. + +On 1 April 2012, the NLD announced that Aung San Suu Kyi had won the vote for a seat in Parliament. A news broadcast on state-run MRTV, reading the announcements of the Union Election Commission, confirmed her victory, as well as her party's victory in 43 of the 45 contested seats, officially making Aung San Suu Kyi the Leader of the Opposition in the Pyidaungsu Hluttaw. + +Although she and other MP-elects were expected to take office on 23 April when the Hluttaws resumed session, National League for Democracy MP-elects, including Aung San Suu Kyi, said they might not take their oaths because of its wording; in its present form, parliamentarians must vow to "safeguard" the constitution. In an address on Radio Free Asia, she said "We don't mean we will not attend the parliament, we mean we will attend only after taking the oath ... Changing that wording in the oath is also in conformity with the Constitution. I don't expect there will be any difficulty in doing it." + +On 2 May 2012, National League for Democracy MP-elects, including Aung San Suu Kyi, took their oaths and took office, though the wording of the oath was not changed. According to the Los Angeles Times, "Suu Kyi and her colleagues decided they could do more by joining as lawmakers than maintaining their boycott on principle." +On 9 July 2012, she attended the Parliament for the first time as a lawmaker. + +2015 general election +On 16 June 2012, Aung San Suu Kyi was finally able to deliver her Nobel acceptance speech (Nobel lecture) at Oslo's City Hall, two decades after being awarded the peace prize. In September 2012, Aung San Suu Kyi received in person the United States Congressional Gold Medal, which is the highest Congressional award. Although she was awarded this medal in 2008, at the time she was under house arrest, and was unable to receive the medal. Aung San Suu Kyi was greeted with bipartisan support at Congress, as part of a coast-to-coast tour in the United States. In addition, Aung San Suu Kyi met President Barack Obama at the White House. The experience was described by Aung San Suu Kyi as "one of the most moving days of my life". In 2014, she was listed as the 61st-most-powerful woman in the world by Forbes. + +On 6 July 2012, Aung San Suu Kyi announced on the World Economic Forum's website that she wanted to run for the presidency in Myanmar's 2015 elections. The current Constitution, which came into effect in 2008, bars her from the presidency because she is the widow and mother of foreigners—provisions that appeared to be written specifically to prevent her from being eligible. + +The NLD won a sweeping victory in those elections, winning at least 255 seats in the House of Representatives and 135 seats in the House of Nationalities. In addition, Aung San Suu Kyi won re-election to the House of Representatives. Under the 2008 constitution, the NLD needed to win at least a two-thirds majority in both houses to ensure that its candidate would become president. Before the elections, Aung San Suu Kyi announced that even though she is constitutionally barred from the presidency, she would hold the real power in any NLD-led government. On 30 March 2016 she became Minister for the President's Office, for Foreign Affairs, for Education and for Electric Power and Energy in President Htin Kyaw's government; later she relinquished the latter two ministries and President Htin Kyaw appointed her State Counsellor, a position akin to a Prime Minister created especially for her. The position of State Counsellor was approved by the House of Nationalities on 1 April 2016 and the House of Representatives on 5 April 2016. The next day, her role as State Counsellor was established. + +State counsellor and foreign minister (2016–2021) + +As soon as she became foreign minister, she invited Chinese Foreign Minister Wang Yi, Canadian Foreign Minister Stephane Dion and Italian Foreign Minister Paolo Gentiloni in April and Japanese Foreign Minister Fumio Kishida in May and discussed how to have good diplomatic relationships with these countries. + +Initially, upon accepting the State Counsellor position, she granted amnesty to the students who were arrested for opposing the National Education Bill, and announced the creation of the commission on Rakhine State, which had a long record of persecution of the Muslim Rohingya minority. However, soon Aung San Suu Kyi's government did not manage with the ethnic conflicts in Shan and Kachin states, where thousands of refugees fled to China, and by 2017 the persecution of the Rohingya by the government forces escalated to the point that it is not uncommonly called a genocide. Aung San Suu Kyi, when interviewed, has denied the allegations of ethnic cleansing. She has also refused to grant citizenship to the Rohingya, instead taking steps to issue ID cards for residency but no guarantees of citizenship. + +Her tenure as State Counsellor of Myanmar has drawn international criticism for her failure to address her country's economic and ethnic problems, particularly the plight of the Rohingya following the 25 August 2017 ARSA attacks (described as "certainly one of the biggest refugee crises and cases of ethnic cleansing since the Second World War"), for the weakening of freedom of the press and for her style of leadership, described as imperious and "distracted and out of touch". + +During the COVID-19 pandemic in Myanmar, Suu Kyi chaired a National Central Committee responsible for coordinating the country's pandemic response. + +Response to the genocide of Rohingya Muslims and refugees +In 2017, critics called for Aung San Suu Kyi's Nobel prize to be revoked, citing her silence over the genocide of Rohingya people in Myanmar. +Some activists criticised Aung San Suu Kyi for her silence on the 2012 Rakhine State riots (later repeated during the 2015 Rohingya refugee crisis), and her indifference to the plight of the Rohingya, Myanmar's persecuted Muslim minority. In 2012, she told reporters she did not know if the Rohingya could be regarded as Burmese citizens. In a 2013 interview with the BBC's Mishal Husain, Aung San Suu Kyi did not condemn violence against the Rohingya and denied that Muslims in Myanmar have been subject to ethnic cleansing, insisting that the tensions were due to a "climate of fear" caused by "a worldwide perception that global Muslim power is 'very great. She did condemn "hate of any kind" in the interview. According to Peter Popham, in the aftermath of the interview, she expressed anger at being interviewed by a Muslim. Husain had challenged Aung San Suu Kyi that almost all of the impact of violence was against the Rohingya, in response to Aung San Suu Kyi's claim that violence was happening on both sides, and Peter Popham described her position on the issue as one of purposeful ambiguity for political gain. + +However, she said that she wanted to work towards reconciliation and she cannot take sides as violence has been committed by both sides. According to The Economist, her "halo has even slipped among foreign human-rights lobbyists, disappointed at her failure to make a clear stand on behalf of the Rohingya minority". However, she has spoken out "against a ban on Rohingya families near the Bangladeshi border having more than two children". + +In a 2015 BBC News article, reporter Jonah Fisher suggested that Aung San Suu Kyi's silence over the Rohingya issue is due to a need to obtain support from the majority Bamar ethnicity as she is in "the middle of a general election campaign". In May 2015, the Dalai Lama publicly called upon her to do more to help the Rohingya in Myanmar, claiming that he had previously urged her to address the plight of the Rohingya in private during two separate meetings and that she had resisted his urging. In May 2016, Aung San Suu Kyi asked the newly appointed United States Ambassador to Myanmar, Scot Marciel, not to refer to the Rohingya by that name as they "are not recognized as among the 135 official ethnic groups" in Myanmar. This followed Bamar protests at Marciel's use of the word "Rohingya". + +In 2016, Aung San Suu Kyi was accused of failing to protect Myanmar's Rohingya Muslims during the Rohingya genocide. State crime experts from Queen Mary University of London warned that Aung San Suu Kyi is "legitimising genocide" in Myanmar. Despite continued persecution of the Rohingya well into 2017, Aung San Suu Kyi was "not even admitting, let alone trying to stop, the army's well-documented campaign of rape, murder and destruction against Rohingya villages". On 4 September 2017, Yanghee Lee, the UN's special rapporteur on human rights in Myanmar, criticised Aung San Suu Kyi's response to the "really grave" situation in Rakhine, saying: "The de facto leader needs to step in—that is what we would expect from any government, to protect everybody within their own jurisdiction." The BBC reported that "Her comments came as the number of Rohingya fleeing to Bangladesh reached 87,000, according to UN estimates", adding that "her sentiments were echoed by Nobel Peace laureate Malala Yousafzai, who said she was waiting to hear from Ms Suu Kyi—who has not commented on the crisis since it erupted". The next day George Monbiot, writing in The Guardian, called on readers to sign a change.org petition to have the Nobel peace prize revoked, criticising her silence on the matter and asserting "whether out of prejudice or out of fear, she denies to others the freedoms she rightly claimed for herself. Her regime excludes—and in some cases seeks to silence—the very activists who helped to ensure her own rights were recognised." The Nobel Foundation replied that there existed no provision for revoking a Nobel Prize. Archbishop Desmond Tutu, a fellow peace prize holder, also criticised Aung San Suu Kyi's silence: in an open letter published on social media, he said: "If the political price of your ascension to the highest office in Myanmar is your silence, the price is surely too steep ... It is incongruous for a symbol of righteousness to lead such a country." On 13 September it was revealed that Aung San Suu Kyi would not be attending a UN General Assembly debate being held the following week to discuss the humanitarian crisis, with a Myanmar government spokesman stating "perhaps she has more pressing matters to deal with". + +In October 2017, Oxford City Council announced that, following a unanimous cross-party vote, the honour of Freedom of the City, granted in 1997 in recognition of her "long struggle for democracy", was to be withdrawn following evidence emerging from the United Nations which meant that she was "no longer worthy of the honour". A few days later, Munsur Ali, a councillor for City of London Corporation, tabled a motion to rescind the Freedom of the City of London: the motion was supported by Catherine McGuinness, chair of the corporation's policy and resources committee, who expressed "distress ... at the situation in Burma and the atrocities committed by the Burmese military". On 13 November 2017, Bob Geldof returned his Freedom of the City of Dublin award in protest over Aung San Suu Kyi also holding the accolade, stating that he does not "wish to be associated in any way with an individual currently engaged in the mass ethnic cleansing of the Rohingya people of north-west Burma". Calling Aung San Suu Kyi a "handmaiden to genocide", Geldof added that he would take pride in his award being restored if it is first stripped from her. The Dublin City Council voted 59–2 (with one abstention) to revoke Aung San Suu Kyi's Freedom of the City award over Myanmar's treatment of the Rohingya people in December 2017, though Lord Mayor of Dublin Mícheál Mac Donncha denied the decision was influenced by protests by Geldof and members of U2. At the same meeting, the Councillors voted 37–7 (with 5 abstentions) to remove Geldof's name from the Roll of Honorary Freemen. + +In March 2018, the United States Holocaust Memorial Museum revoked Aung San Suu Kyi's Elie Wiesel Award, awarded in 2012, citing her failure "to condemn and stop the military's brutal campaign" against Rohingya Muslims. + +In May 2018, Aung San Suu Kyi was considered complicit in the crimes against Rohingyas in a report by Britain's International Development Committee. + +In August 2018, it was revealed that Aung San Suu Kyi would be stripped of her Freedom of Edinburgh award over her refusal to speak out against the crimes committed against the Rohingya. She had received the award in 2005 for promoting peace and democracy in Burma. This will be only the second time that anyone has ever been stripped of the award, after Charles Stewart Parnell lost it in 1890 due to a salacious affair. Also in August, a UN report, while describing the violence as genocide, added that Aung San Suu Kyi did as little as possible to prevent it. + +In early October 2018, both the Canadian Senate and its House of Commons voted unanimously to strip Aung San Suu Kyi of her honorary citizenship. This decision was caused by the Government of Canada's determination that the treatment of the Rohingya by Myanmar's government amounts to genocide. + +On 11 November 2018, Amnesty International announced it was revoking her Ambassador of Conscience award. +In December 2019, Aung San Suu Kyi appeared in the International Court of Justice at The Hague where she defended the Burmese military against allegations of genocide against the Rohingya. In a speech of over 3,000 words, Aung San Suu Kyi did not use the term "Rohingya" in describing the ethnic group. She stated that the allegations of genocide were "incomplete and misleading", claiming that the situation was actually a Burmese military response to attacks by the Arakan Rohingya Salvation Army. She also questioned how there could be "genocidal intent" when the Burmese government had opened investigations and also encouraged Rohingya to return after being displaced. However, experts have largely criticized the Burmese investigations as insincere, with the military declaring itself innocent and the government preventing a visit from investigators from the United Nations. Many Rohingya have also not returned due to perceiving danger and a lack of rights in Myanmar. + +In January 2020, the International Court of Justice decided that there was a "real and imminent risk of irreparable prejudice to the rights" of the Rohingya. The court also took the view that the Burmese government's efforts to remedy the situation "do not appear sufficient" to protect the Rohingya. Therefore, the court ordered the Burmese government to take "all measures within its power" to protect the Rohingya from genocidal actions. The court also instructed the Burmese government to preserve evidence and report back to the court at timely intervals about the situation. + +Arrests and prosecution of journalists +In December 2017, two Reuters journalists, Wa Lone and Kyaw Soe Oo, were arrested while investigating the Inn Din massacre of Rohingyas. Suu Kyi publicly commented in June 2018 that the journalists "weren't arrested for covering the Rakhine issue", but because they had broken Myanmar's Official Secrets Act. As the journalists were then on trial for violating the Official Secrets Act, Aung San Suu Kyi's presumption of their guilt was criticized by rights groups for potentially influencing the verdict. American diplomat Bill Richardson said that he had privately discussed the arrest with Suu Kyi, and that Aung San Suu Kyi reacted angrily and labelled the journalists "traitors". A police officer testified that he was ordered by superiors to use entrapment to frame and arrest the journalists; he was later jailed and his family evicted from their home in the police camp. The judge found the journalists guilty in September 2018 and to be jailed for seven years. Aung San Suu Kyi reacted to widespread international criticism of the verdict by stating: "I don't think anyone has bothered to read" the judgement as it had "nothing to do with freedom of expression at all", but the Official Secrets Act. She also challenged critics to "point out where there has been a miscarriage of justice", and told the two Reuters journalists that they could appeal their case to a higher court. + +In September 2018, the Office of the United Nations High Commissioner for Human Rights issued a report that since Aung San Suu Kyi's party, the NLD, came to power, the arrests and criminal prosecutions of journalists in Myanmar by the government and military, under laws which are too vague and broad, have "made it impossible for journalists to do their job without fear or favour." + +2021 arrest and trial + +On 1 February 2021, Aung San Suu Kyi was arrested and deposed by the Myanmar military, along with other leaders of her National League for Democracy (NLD) party, after the Myanmar military declared the November 2020 general election results fraudulent. A 1 February court order authorized her detainment for 15 days, stating that soldiers searching her Naypyidaw villa had uncovered imported communications equipment lacking proper paperwork. Aung San Suu Kyi was transferred to house arrest on the same evening, and on 3 February was formally charged with illegally importing ten or more walkie-talkies. She faces up to three years in prison for the charges. According to The New York Times, the charge "echoed previous accusations of esoteric legal crimes (and) arcane offenses" used by the military against critics and rivals. As of 9 February, Aung San Suu Suu Kyi continues to be held incommunicado, without access to international observers or legal representation of her choice. + +US President Joe Biden raised the threat of new sanctions as a result of the Myanmar military coup. In a statement, the UN Secretary-General António Guterres believes "These developments represent a serious blow to democratic reforms in Myanmar." Volkan Bozkir, President of the UN General Assembly, also voiced his concerns, having tweeted "Attempts to undermine democracy and rule of law are unacceptable", and called for the "immediate release" of the detained NLD party leaders. + +On 1 April 2021, Aung San Suu Kyi was charged with the fifth offence in relation to violating the official secrets act. According to her lawyer, it is the most serious charge brought against her after the coup and could carry a sentence of up to 14 years in prison if convicted. On 12 April 2021, Aung San Suu Kyi was hit with another charge, this time "under section 25 of the natural disaster management law". According to her lawyer, it is her sixth indictment. She appeared in court via video link and now faces five charges in the capital Naypyidaw and one in Yangon. + +On 28 April 2021, the National Unity Government (NUG), in which Aung San Suu Kyi symbolically retained her position, anticipated that there would be no talks with the junta until all political prisoners, including her, are set free. This move by her supporters come after an ASEAN-supported consensus with the junta leadership in the past days. However, on 8 May 2021, the junta designated NUG as a terrorist organization and warned citizens not to cooperate, nor to give aid to the parallel government, stripping Aung San Suu Kyi of her symbolic position. On 10 May 2021, her lawyer said she would appear in court in person for the first time since her arrest after the Supreme Court ruled that she could attend in person and meet her lawyers. She had been previously only allowed to do so remotely from her home. On 21 May 2021, a military junta commission was formed to dissolve Aung San Suu Kyi's National League for Democracy (NLD) on grounds of election fraud in the November 2020 election. On 22 May 2021, during his first interview since the coup, junta leader Min Aung Hlaing reported that she was in good health at her home and that she would appear in court in a matter of days. On 23 May 2021, the European Union expressed support for Aung San Suu Kyi's party and condemned the commission aimed at dissolving the party, echoing the NLD's statement released earlier in the week. + +On 24 May 2021, Aung San Suu Kyi appeared in person in court for the first time since the coup to face the "incitement to sedition" charge against her. During the 30-minute hearing, she said that she was not fully aware of what was going on outside as she had no access to full information from the outside and refused to respond on the matters. She was also quoted on the possibility of her party’s forced dissolution as "Our party grew out of the people so it will exist as long as people support it." In her meeting with her lawyers, Aung San Suu Kyi also wished people "good health". + +On 2 June 2021, it was reported that the military had moved her (as well as Win Myint) from their homes to an unknown location. + +On 10 June 2021, Aung San Suu Kyi was charged with corruption, the most serious charge brought against her, which carries a maximum penalty of 15 years' imprisonment. Aung San Suu Kyi's lawyers say the charges are made to keep her out of the public eye. + +On 14 June 2021, the trial against Aung San Suu Kyi began. Any conviction would prevent her from running for office again. Aung San Suu Kyi's lawyers attempted to have prosecution testimony against her on the sedition charge disqualified but the motion was denied by the judge. + +On 13 September 2021, court proceedings were to resume against her, but it was postponed due to Aung San Suu Kyi presenting "minor health issues" that impeded her from attending the court in person. + +On 4 October 2021, Aung San Suu Kyi asked the judge to reduce her times of court appearances because of her fragile health. Aung San Suu Kyi described her health as "strained". + +In November, the Myanmar courts deferred the first verdicts in the trial without further explanation or giving dates. In the same month, she was again charged with corruption, related to the purchase and rental of a helicopter, bringing the total of charges to nearly a dozen. + +On 6 December 2021, Suu Kyi was sentenced to 4 years in jail. Suu Kyi, who is still facing multiple charges and further sentences, was sentenced on the charge of inciting dissent and violating COVID-19 protocols. Following a partial pardon by the chief of the military government, Aung San Suu Kyi's four-year sentence was reduced to two years' imprisonment. + +On 10 January 2022, the military court in Myanmar sentenced Suu Kyi to an additional four years in prison on a number of charges including "importing and owning walkie-talkies" and "breaking coronavirus rules". The trials, which are closed to the public, the media, and any observers, were described as a "courtroom circus of secret proceedings on bogus charges" by the deputy director for Asia of Human Rights Watch. + +On 27 April 2022, Aung San Suu Kyi was sentenced to five years in jail on corruption charges. + +On 22 June 2022, junta authorities ordered that all further legal proceedings against Suu Kyi will take place in prison venues, instead of a courtroom. No explanation of the decision was given. Citing unidentified sources, the BBC reported that Suu Kyi was also moved on 22 June from house arrest, where she had had close companions, to solitary confinement in a specially-built area inside a prison in Nay Pyi Taw. This is the same prison in which Win Myint had similarly been placed in solitary confinement. The military confirmed that Suu Kyi had been moved to prison. + +On 15 August 2022, sources following Aung San Suu Kyi's court proceedings said that she was sentenced to an additional six years' imprisonment after being found guilty on four corruption charges, bringing her overall sentences to 17 years in prison. In September 2022, she was convicted of election fraud and breaching the state's secrets act and sentenced to a total of six years in prison for both convictions, increasing her overall sentence to 23 years in prison. By 12 October 2022, she had been sentenced to 26 years imprisonment on ten charges in total, including five corruption charges. On 30 December 2022, her trials ended with another conviction and an additional sentence of seven years' imprisonment for corruption. Aung San Suu Kyi's final sentence is of 33 years in prison. + +On 12 July 2023, Thailand's foreign minister Don Pramudwinai said at the ASEAN Foreign Ministers' Meeting in Jakarta that he met with Aung San Suu Kyi during his visit to Myanmar. On 1 August 2023, the military junta granted Suu Kyi a partial pardon, reducing her sentence to a total of 27 years in prison. Prior to the pardon, she was moved from prison to a VIP government residence, according to an official from NLD party. + +However, it was reported that since the beginning of September 2023, she is back in prison. The exact time when she was sent back to prison is unknown. Since January, Aung San Suu Kyi and her lawyers are trying to get six corruption charges overturned. To this date, the requests are repeatedly denied. + +Political beliefs + +Asked what democratic models Myanmar could look to, she said: "We have many, many lessons to learn from various places, not just the Asian countries like South Korea, Taiwan, Mongolia, and Indonesia." She also cited "eastern Europe and countries, which made the transition from communist autocracy to democracy in the 1980s and 1990s, and the Latin American countries, which made the transition from military governments. And we cannot of course forget South Africa, because although it wasn't a military regime, it was certainly an authoritarian regime." She added: "We wish to learn from everybody who has achieved a transition to democracy, and also ... our great strong point is that, because we are so far behind everybody else, we can also learn which mistakes we should avoid." + +In a nod to the deep US political divide between Republicans led by Mitt Romney and the Democrats by Obama—then battling to win the 2012 presidential election—she stressed, "Those of you who are familiar with American politics I'm sure understand the need for negotiated compromise." + +Related organisations + + Freedom Now, a Washington, D.C.-based non-profit organisation, was retained in 2006 by a member of her family to help secure Aung San Suu Kyi's release from house arrest. The organisation secured several opinions from the UN Working Group on Arbitrary Detention that her detention was in violation of international law; engaged in political advocacy such as spearheading a letter from 112 former Presidents and Prime Ministers to UN Secretary-General Ban Ki-moon urging him to go to Burma to seek her release, which he did six weeks later; and published numerous op-eds and spoke widely to the media about her ongoing detention. Its representation of her ended when she was released from house arrest on 13 November 2010. + Aung San Suu Kyi has been an honorary board member of International IDEA and ARTICLE 19 since her detention, and has received support from these organisations. + The Vrije Universiteit Brussel and the University of Louvain (UCLouvain), both located in Belgium, granted her the title of Doctor Honoris Causa. + In 2003, the Freedom Forum recognised Aung San Suu Kyi's efforts to promote democracy peacefully with the Al Neuharth Free Spirit of the Year Award, in which she was presented over satellite because she was under house arrest. She was awarded one million dollars. + In June of each year, the U.S. Campaign for Burma organises hundreds of "Arrest Yourself" house parties around the world in support of Aung San Suu Kyi. At these parties, the organisers keep themselves under house arrest for 24 hours, invite their friends, and learn more about Burma and Aung San Suu Kyi. + The Freedom Campaign, a joint effort between the Human Rights Action Center and US Campaign for Burma, looks to raise worldwide attention to the struggles of Aung San Suu Kyi and the people of Burma. + The Burma Campaign UK is a UK-based NGO (Non-Governmental Organisation) that aims to raise awareness of Burma's struggles and follow the guidelines established by the NLD and Aung San Suu Kyi. + St Hugh's College, Oxford, where she studied, had a Burmese theme for their annual ball in support of her in 2006. The university later awarded her an honorary doctorate in civil law on 20 June 2012 during her visit to her alma mater. + Aung San Suu Kyi is the official patron of The Rafto Human Rights House in Bergen, Norway. She received the Thorolf Rafto Memorial Prize in 1990. + She was made an honorary free person of the City of Dublin, Ireland in November 1999, although a space had been left on the roll of signatures to symbolize her continued detention. This was subsequently revoked on 13 December 2017. + In November 2005 the human rights group Equality Now proposed Aung Sun Suu Kyi as a potential candidate, among other qualifying women, for the position of U.N. Secretary General. In the proposed list of qualified women Aung San Suu Kyi was recognised by Equality Now as the Prime Minister-Elect of Burma. + The UN' special envoy to Myanmar, Ibrahim Gambari, met Aung San Suu Kyi on 10 March 2008 before wrapping up his trip to the military-ruled country. + Aung San Suu Kyi was an honorary member of The Elders, a group of eminent global leaders brought together by Nelson Mandela. Her ongoing detention meant that she was unable to take an active role in the group, so The Elders placed an empty chair for her at their meetings. The Elders have consistently called for the release of all political prisoners in Burma. Upon her election to parliament, she stepped down from her post. + In 2010, Aung San Suu Kyi was given an honorary doctorate from the University of Johannesburg. + In 2011, Aung San Suu Kyi was named the Guest Director of the 45th Brighton Festival. + She was part of the international jury of Human Rights Defenders and Personalities who helped to choose a universal Logo for Human Rights in 2011. + In June 2011, the BBC announced that Aung San Suu Kyi was to deliver the 2011 Reith Lectures. The BBC covertly recorded two lectures with Aung San Suu Kyi in Burma, which were then smuggled out of the country and brought back to London. The lectures were broadcast on BBC Radio 4 and the BBC World Service on 28 June 2011 and 5 July 2011. + 8 March 2012, Canadian Foreign Affairs Minister John Baird presented Aung San Suu Kyi a certificate of honorary Canadian citizenship and an informal invitation to visit Canada. The honorary citizenship was revoked in September 2018 due to the Rohingya conflict. + In April 2012, British Prime Minister David Cameron became the first leader of a major world power to visit Aung San Suu Kyi and the first British prime minister to visit Burma since the 1950s. In his visit, Cameron invited Aung San Suu Kyi to Britain where she would be able to visit her 'beloved' Oxford, an invitation which she later accepted. She visited Britain on 19 June 2012. + In 2012 she received the Honorary degree of Doctor of Civil Law from the University of Oxford. + In May 2012, Aung San Suu Kyi received the inaugural Václav Havel Prize for Creative Dissent of the Human Rights Foundation. + 29 May 2012 PM Manmohan Singh of India visited Aung San Suu Kyi. In his visit, PM invited Aung San Suu Kyi to India as well. She started her six-day visit to India on 16 November 2012, where among the places she visited was her alma mater Lady Shri Ram College in New Delhi. +In 2012, Aung San Suu Kyi set up the charity Daw Khin Kyi Foundation to improve health, education and living standards in underdeveloped parts of Myanmar. The charity was named after Aung San Suu Kyi's mother. Htin Kyaw played a leadership role in the charity before his election as President of Myanmar. The charity runs a Hospitality and Catering Training Academy in Kawhmu Township, in Yangon Region, and runs a mobile library service which in 2014 had 8000 members. + Seoul National University in South Korea conferred an honorary doctorate degree to Aung San Suu Kyi in February 2013. + University of Bologna, Italy conferred an honorary doctorate degree in philosophy to Aung San Suu Kyi in October 2013. + Monash University, The Australian National University, University of Sydney and University of Technology, Sydney conferred an honorary degree to Aung San Suu Kyi in November 2013. + +In popular culture + +The life of Aung San Suu Kyi and her husband Michael Aris is portrayed in Luc Besson's 2011 film The Lady, in which they are played by Michelle Yeoh and David Thewlis. Yeoh visited Aung San Suu Kyi in 2011 before the film's release in November. In the John Boorman's 1995 film Beyond Rangoon, Aung San Suu Kyi was played by Adelle Lutz. + +Irish songwriters Damien Rice and Lisa Hannigan released in 2005 the single "Unplayed Piano", in support of the Free Aung San Suu Kyi 60th Birthday Campaign that was happening at the time. U2's Bono wrote the song "Walk On" in tribute to Aung San Suu Kyi (and wore a shirt with her name and image upon it), and he publicized her plight during the U2 360° Tour, 2009–2011. Saxophonist Wayne Shorter composed a song titled "Aung San Suu Kyi". It appears on his albums 1+1 (with pianist Herbie Hancock) and Footprints Live!. + +Health problems +Aung San Suu Kyi underwent surgery for a gynecological condition in September 2003 at Asia Royal Hospital during her house arrest. She also underwent minor foot surgery in December 2013 and eye surgery in April 2016. In June 2012, her doctor Tin Myo Win said that she had no serious health problems, but weighed only , had low blood pressure, and could become weak easily. + +After being arrested and detained on 1 February 2021, there were concerns that Aung San Suu Kyi's health is deteriorating. However, according to military's spokesperson Zaw Min Tun, special attention is given to her health and living condition. Don Pramudwinai also said that "she was in good health, both physically and mentally". + +Although a junta spokesperson claimed that she is in good health, since being sent back to prison in September 2023, it is reported that her health condition is worsening and "suffering a series of toothache and unable to eat". Her request to see a dentist had been denied. Her son is urging the junta to allow Aung San Suu Kyi to receive medical assistance. + +Books + Freedom from Fear (1991) + Letters from Burma (1991) + Let's Visit Nepal (1985) (ISBN 978-0222009814) + +Honours + List of honours of Aung San Suu Kyi + +See also + + List of civil rights leaders + List of Nobel laureates affiliated with Kyoto University + State Counsellor of Myanmar + List of foreign ministers in 2017 + List of current foreign ministers + +Notes + +References + +Bibliography + + Miller, J. E. (2001). Who's Who in Contemporary Women's Writing. Routledge. + Reid, R., Grosberg, M. (2005). Myanmar (Burma). Lonely Planet. . + Stewart, Whitney (1997). Aung San Suu Kyi: Fearless Voice of Burma. Twenty-First Century Books. . + +Further reading + Combs, Daniel. Until the World Shatters: Truth, Lies, and the Looting of Myanmar (2021). + + Aung San Suu Kyi (Modern Peacemakers) (2007) by Judy L. Hasday, + The Lady: Aung San Suu Kyi: Nobel Laureate and Burma's Prisoner (2002) by Barbara Victor, , or 1998 hardcover: + The Lady and the Peacock: The Life of Aung San Suu Kyi (2012) by Peter Popham, + Perfect Hostage: A Life of Aung San Suu Kyi (2007) by Justin Wintle, + Tyrants: The World's 20 Worst Living Dictators (2006) by David Wallechinsky, + Aung San Suu Kyi (Trailblazers of the Modern World) (2004) by William Thomas, + No Logo: No Space, No Choice, No Jobs (2002) by Naomi Klein + Mental culture in Burmese crisis politics: Aung San Suu Kyi and the National League for Democracy (ILCAA Study of Languages and Cultures of Asia and Africa Monograph Series) (1999) by Gustaaf Houtman, + Aung San Suu Kyi: Standing Up for Democracy in Burma (Women Changing the World) (1998) by Bettina Ling + Prisoner for Peace: Aung San Suu Kyi and Burma's Struggle for Democracy (Champions of Freedom Series) (1994) by John Parenteau, + Des femmes prix Nobel de Marie Curie à Aung San Suu Kyi, 1903–1991 (1992) by Charlotte Kerner, Nicole Casanova, Gidske Anderson, + Aung San Suu Kyi, towards a new freedom (1998) by Chin Geok Ang + Aung San Suu Kyi's struggle: Its principles and strategy (1997) by Mikio Oishi + Finding George Orwell in Burma (2004) by Emma Larkin + Character Is Destiny: Inspiring Stories Every Young Person Should Know and Every Adult Should Remember (2005) by John McCain, Mark Salter. Random House + + Under the Dragon: A Journey Through Burma (1998/2010) by Rory MacLean + +External links + + Aung San Suu Kyi's website (Site appears to be inactive. Last posting was in July 2014) + + + + + + +|- + +|- + +|- + +|- + +|- + +|- + +|- + +|- + +|- + +|- + +|- + +|- + +|- + + +Prime Ministers of Myanmar +21st-century women prime ministers +1945 births +20th-century Burmese women writers +20th-century Burmese writers +21st-century Burmese politicians +21st-century Burmese women politicians +21st-century Burmese women writers +21st-century Burmese writers +Alumni of SOAS University of London +Alumni of St Hugh's College, Oxford +Amnesty International prisoners of conscience held by Myanmar +Buddhist pacifists +Burmese activists +Burmese democracy activists +Burmese human rights activists +Burmese Nobel laureates +Burmese pacifists +Burmese prisoners and detainees +Burmese revolutionaries +Burmese socialists +Burmese Theravada Buddhists +Burmese women activists +Burmese women diplomats +Burmese women in politics +Civil rights activists +Congressional Gold Medal recipients +Family of Aung San +Fellows of St Hugh's College, Oxford +Fellows of the Royal College of Surgeons of Edinburgh +Female foreign ministers +Female heads of government +Foreign ministers of Myanmar +Gandhians +Heads of government who were later imprisoned +Honorary Companions of the Order of Australia +International Simón Bolívar Prize recipients +Lady Shri Ram College alumni +Leaders ousted by a coup +Living people +Members of Pyithu Hluttaw +National League for Democracy politicians +Nobel Peace Prize laureates +Nonviolence advocates +Olof Palme Prize laureates +Activists from Yangon +Politicians from Yangon +People stripped of honorary degrees +Presidential Medal of Freedom recipients +Prisoners and detainees of Myanmar +Recipients of the Four Freedoms Award +Sakharov Prize laureates +Women civil rights activists +Women government ministers of Myanmar +Women Nobel laureates +Women opposition leaders +Abraham Joshua Heschel (January 11, 1907 – December 23, 1972) was a Polish-American rabbi and one of the leading Jewish theologians and Jewish philosophers of the 20th century. Heschel, a professor of Jewish mysticism at the Jewish Theological Seminary of America, authored a number of widely read books on Jewish philosophy and was a leader in the civil rights movement. + +Biography +Abraham Joshua Heschel was born in Warsaw in 1907 as the youngest of six children of Moshe Mordechai Heschel and Reizel Perlow Heschel. He was descended from preeminent European rabbis on both sides of his family. His paternal great-great-grandfather and namesake was Rebbe Avraham Yehoshua Heshel of Apt in present-day Poland. His mother was also a descendant of Avraham Yehoshua Heshel and other Hasidic dynasties. His siblings were Sarah, Dvora Miriam, Esther Sima, Gittel, and Jacob. Their father Moshe died of influenza in 1916 when Abraham was nine. He was tutored by a Gerrer Hasid who introduced him to the thought of Rabbi Menachem Mendel of Kotzk. + +After a traditional yeshiva education and studying for Orthodox rabbinical ordination (semicha), Heschel pursued his doctorate at the University of Berlin and rabbinic ordination at the non-denominational Hochschule für die Wissenschaft des Judentums. There he studied under notable scholars including Hanoch Albeck, Ismar Elbogen, Julius Guttmann, Alexander Guttmann, and Leo Baeck. His mentor in Berlin was David Koigen. Heschel later taught Talmud at the Hochschule. He joined a Yiddish poetry group, Jung Vilna, and in 1933, published a volume of Yiddish poems, Der Shem Hamefoyrosh: Mentsch, dedicated to his father. + +In late October 1938, when Heschel was living in a rented room in the home of a Jewish family in Frankfurt, he was arrested by the Gestapo and deported to Poland in the Polenaktion. He spent ten months lecturing on Jewish philosophy and Torah at Warsaw's Institute for Jewish Studies. Six weeks before the German invasion of Poland, Heschel left Warsaw for London with the help of Julian Morgenstern, president of Hebrew Union College, who had been working to obtain visas for Jewish scholars in Europe and Alexander Guttmann, later his colleague in Cincinnati, who secretly re-wrote his ordination certificate to meet American visa requirements. + +Heschel's sister Esther was killed in a German bombing. His mother was murdered by the Nazis, and two other sisters, Gittel and Devorah, died in Nazi concentration camps. He never returned to Germany, Austria or Poland. He once wrote, "If I should go to Poland or Germany, every stone, every tree would remind me of contempt, hatred, murder, of children killed, of mothers burned alive, of human beings asphyxiated." + +Heschel arrived in New York City in March 1940. He served on the faculty of Hebrew Union College (HUC), the main seminary of Reform Judaism, in Cincinnati for five years. In 1946, he took a position at the Jewish Theological Seminary of America (JTS) in New York City, the main seminary of Conservative Judaism. He served as professor of Jewish ethics and Mysticism until his death in 1972. At the time of his death, Heschel lived near JTS at 425 Riverside Drive in Manhattan. + +Heschel married Sylvia Straus, a concert pianist, on December 10, 1946, in Los Angeles. Their daughter, Susannah Heschel, became a Jewish scholar in her own right. + +Ideology + +Heschel explicated many facets of Jewish thought, including studies on medieval Jewish philosophy, Kabbalah, and Hasidic philosophy. According to some scholars, he was more interested in spirituality than in critical text study; the latter was a specialty of many scholars at JTS. He was not given a graduate assistant for many years and he was mainly relegated to teach in the education school or the Rabbinical school, not in the academic graduate program. Heschel became friendly with his colleague Mordecai Kaplan. Though they differed in their approaches to Judaism, they had a very cordial relationship and visited each other's homes from time to time. + +Heschel believed that the teachings of the Hebrew prophets were a clarion call for social action in the United States and inspired by this belief, he worked for African Americans' civil rights and spoke out against the Vietnam War. + +He also criticized what he specifically called "pan-halakhism", or an exclusive focus upon religiously compatible behavior to the neglect of the non-legalistic dimension of rabbinic tradition. + +Heschel is notable as a recent proponent of what one scholar calls the "Nachmanidean" school of Jewish thought - emphasizing the mutually dependent relationship between God and man - as opposed to the "Maimonidean" school in which God is independent and unchangeable. In Heschel's language, the "Maimonidean" perspective is associated with Rabbi Yishmael and the "Nachmanidean" perspective with Rabbi Akiva; according to Heschel neither perspective should be adopted in isolation, but rather both are interwoven with the other. + +Heschel described kabbalah as an outgrowth of classical rabbinic sources which describe God's dependence on man to implement the divine plan for the world. This contrasts with scholars like Gershon Scholem who saw kabbalah as reflecting the influence of non-Jewish thought. While Scholem's school focused on the metaphysics and history of kabbalistic thought, Heschel focused on kabbalistic descriptions of the human religious experience. In recent years, a growing body of kabbalah scholarship has followed Heschel's emphasis on the mystical experience of kabbalah and on its continuity with earlier Jewish sources. + +Influence outside Judaism + +Heschel is a widely read Jewish theologian whose most influential works include Man Is Not Alone, God in Search of Man, The Sabbath, and The Prophets. At the Second Vatican Council, as a representative of American Jews, Heschel persuaded the Catholic Church to eliminate or modify passages in its liturgy which demeaned the Jews, or referred to an expected conversion of the Jews to Christianity. His theological works argued that religious experience is a fundamentally human impulse, not just a Jewish one. He believed that no religious community could claim a monopoly on religious truth. For these and other reasons, Martin Luther King Jr. called Heschel "a truly great prophet." Heschel actively participated in the Civil Rights movement, and was a participant in the third Selma to Montgomery march, accompanying Dr. King and John Lewis. + +Published works + The Earth Is the Lord's: The Inner World of the Jew in Eastern Europe. 1949. + Man Is Not Alone: A Philosophy of Religion. 1951. + The Sabbath: Its Meaning for Modern Man. 1951. + Man's Quest for God: Studies in Prayer and Symbolism. 1954. + God in Search of Man: A Philosophy of Judaism. 1955. + The Prophets. 1962. + Who Is Man? 1965. + Israel: An Echo of Eternity. 1969. + A Passion for Truth. 1973. + I asked for Wonder: A spiritual anthology. 1983. + Heavenly Torah: As Refracted Through the Generations. 2005. + ; Theology of Ancient Judaism. [Hebrew]. 2 vols. London: Soncino Press, 1962. Third volume, New York: Jewish Theological Seminary, 1995. + The Ineffable Name of God: Man: Poems. 2004. + . [Yiddish]. 2 v. (694 p.) Tel-Aviv: ha-Menorah, 1973. Added t.p.: Kotzk: the struggle for integrity (A Hebrew translation of vol. 1, Jerusalem: Magid, 2015). + (). 45 p. Originally published: New-York: Shoken, 1946. + +Man Is Not Alone (1951) +Man Is Not Alone: A Philosophy of Religion offers Heschel's views on how people can comprehend God. Judaism views God as being radically different from humans, so Heschel explores the ways that Judaism teaches that a person may have an encounter with the ineffable. A recurring theme in this work is the radical amazement that people feel when experiencing the presence of the Divine. Heschel then goes on to explore the problems of doubts and faith; what Judaism means by teaching that God is one; the essence of humanity and the problem of human needs; the definition of religion in general and of Judaism in particular; and human yearning for spirituality. He offers his views as to Judaism being a pattern for life. + +The Sabbath (1951) +The Sabbath: Its Meaning for Modern Man is a work on the nature and celebration of Shabbat, the Jewish Sabbath. It is rooted in the thesis that Judaism is a religion of time, not space, and that the Sabbath symbolizes the sanctification of time. Heschel wrote that "Technical civilization is man's conquest of space. It is a triumph frequently achieved by sacrificing an essential ingredient of existence, namely, time." And that "To enhance our power in the world of space is our main objective" while warning that "We have often suffered from degradation by poverty, now we are threatened with degradation through power." + +God in Search of Man (1955) +God in Search of Man: A Philosophy of Judaism is a companion volume to Man Is Not Alone. In this book Heschel discusses the nature of religious thought, how thought becomes faith, and how faith creates responses in the believer. He discusses ways that people can seek God's presence, and the radical amazement that we receive in return. He offers a criticism of nature worship; a study of humanity's metaphysical loneliness, and his view that we can consider God to be in search of humanity. The first section concludes with a study of Jews as a chosen people. Section two deals with the idea of revelation, and what it means for one to be a prophet. This section gives us his idea of revelation as an event, as opposed to a process. This relates to Israel's commitment to God. Section three discusses his views of how a Jew should understand the nature of Judaism as a religion. He discusses and rejects the idea that mere faith (without law) alone is enough, but then cautions against rabbis he sees as adding too many restrictions to Jewish law. He discusses the need to correlate ritual observance with spirituality and love, the importance of Kavanah (intention) when performing mitzvot. He engages in a discussion of religious behaviorism—when people strive for external compliance with the law, yet disregard the importance of inner devotion. + +The Prophets (1962) +This work started out as his PhD thesis in German, which he later expanded and translated into English. Originally published in a two-volume edition, this work studies the books of the Hebrew prophets. It covers their lives and the historical context that their missions were set in, summarizes their work, and discusses their psychological state. In it Heschel puts forward what would become a central idea in his theology: that the prophetic (and, ultimately, Jewish) view of God is best understood not as anthropomorphic (that God takes human form) but rather as anthropopathic—that God has human feelings. + +In his book The Prophets, Abraham Joshua Heschel describes the unique aspect of the Jewish prophets as compared to other similar figures. Whereas other nations have soothsayers and diviners who attempt to discover the will of their gods, according to Heschel the Hebrew prophets are characterized by their experience of what he calls theotropism—God turning towards humanity. Heschel argues for the view of Hebrew prophets as receivers of the "Divine Pathos", of the wrath and sorrow of God over his nation that has forsaken him. In this view, prophets do not speak for God so much as they remind their audience of God's voice for the voiceless, the poor and oppressed. + +He writes: + +Torah min HaShamayim (1962) +Many consider Heschel's Torah min HaShamayim BeAspaklariya shel HaDorot, (Torah from Heaven in the mirror of the generations) to be his masterwork. The three volumes of this work are a study of classical rabbinic theology and aggadah, as opposed to halakha (Jewish law). It explores the views of the rabbis in the Mishnah, Talmud and Midrash about the nature of Torah, the revelation of God to mankind, prophecy, and the ways that Jews have used scriptural exegesis to expand and understand these core Jewish texts. In this work, Heschel views the 2nd century sages Rabbi Akiva and Ishmael ben Elisha as paradigms for the two dominant world-views in Jewish theology + +Two Hebrew volumes were published during his lifetime by Soncino Press, and the third Hebrew volume was published posthumously by JTS Press in the 1990s. A new edition, including an expanded third volume, due to manuscripts which were found and edited by Dr. Dror Bondi, was published by Magid Press in 2021. An English translation of all three volumes, with notes, essays and appendices, was translated and edited by Rabbi Gordon Tucker, entitled Heavenly Torah: As Refracted Through the Generations. In its own right it can be the subject of intense study and analysis, and provides insight into the relationship between God and Man beyond the world of Judaism and for all Monotheism. + +Who is Man? (1965) +Heschel discusses the nature and role of man. In these three lectures, originally delivered in somewhat different form as The Raymond Fred West Memorial Lectures at Stanford University in May 1963, Dr. Heschel inquires into the logic of being human: What is meant by being human? What are the grounds on which to justify a human being's claim to being human? In the author's words, “We have never been as openmouthed and inquisitive, never as astonished and embarrassed at our ignorance about man. We know what he makes, but we do not know what he is or what to expect of him. Is it not conceivable that our entire civilization is built upon a misinterpretation of man? Or that the tragedy of man is due to the fact that he is a being who has forgotten the question: Who is Man? The failure to identify himself, to know what is authentic human existence, leads him to assume a false identity, to pretend to be what he is unable to be or to not accepting what is at the very root of his being. Ignorance about man is not lack of knowledge, but false knowledge.” + +Prophetic Inspiration After the Prophets (1966) +Heschel wrote a series of articles, originally in Hebrew, on the existence of prophecy in Judaism after the destruction of the Holy Temple in Jerusalem in 70 CE. These essays were translated into English and published as Prophetic Inspiration After the Prophets: Maimonides and Others by the American Judaica publisher Ktav. + +The publisher of this book states, "The standard Jewish view is that prophecy ended with the ancient prophets, somewhere early in the Second Temple era. Heschel demonstrated that this view is not altogether accurate. Belief in the possibility of continued prophetic inspiration, and belief in its actual occurrence existed throughout much of the medieval period, and it even exists in modern times. Heschel's work on prophetic inspiration in the Middle Ages originally appeared in two long Hebrew articles. In them, he concentrated on the idea that prophetic inspiration was even possible in post-Talmudic times, and, indeed, it had taken place at various schools in various times, from the Geonim to Maimonides and beyond." + +Awards and commemoration +1970: National Jewish Book Award in the Jewish Thought category for Israel: An Echo of Eternity +Five schools have been named for Heschel, in Buenos Aires, Argentina the rabbinical School of the Seminario Rabinico Latinoamericano, the Upper West Side of New York City, Northridge, California, Agoura Hills, California, and Toronto, Ontario, Canada. In 2009, a highway in Missouri was named "Dr. Abraham Joshua Heschel Highway" after a Springfield, Missouri area Neo-Nazi group cleaned the stretch of highway as part of an "Adopt-A-Highway" plan. Heschel's daughter, Susannah, has objected to the adoption of her father's name in this context. + +Heschel's papers are held in the Rubenstein Rare Book & Manuscript Library at Duke University. + +On 17 October 2022, John Paul II Catholic University of Lublin inaugurated the Abraham J. Heschel Center for Catholic-Jewish Relations, attended by Catholic and Jewish figures, including Rabbi Abraham Skorka, Susannah Heschel, Latin Patriarch of Jerusalem Archbishop Pierbattista Pizzaballa, and Archbishop Stanisław Budzik of Lublin. Pope Francis has welcomed the establishment of the Heschel Center. + +See also + + List of peace activists + +References + +Further reading +Abraham Joshua Heschel: Prophetic Witness & Spiritual Radical: Abraham Joshua Heschel in America, 1940–1972, biography by Edward K. Kaplan + "The Encyclopedia of Hasidism" edited by Rabinowicz, Tzvi M.: Jason Aronson, Inc., 1996. + +External links + + Guide to the Abraham Joshua Heschel Papers, David M. Rubenstein Rare Book & Manuscript Library, Duke University. + Heschel's role in Vatican II and his advocacy of interreligious respect + Alan Brill Review of Heavenly Torah + Arnold Jacob Wolf Review of Heavenly Torah + David Blumenthal review of Heavenly Torah + About Rabbi A. J. Heschel The Heschel Center for Environmental Learning and Leadership + +1907 births +1972 deaths +Activists for African-American civil rights +American Conservative rabbis +American ethicists +American Jewish theologians +American pacifists +Hebrew Union College – Jewish Institute of Religion faculty +Humboldt University of Berlin alumni +Jewish pacifists +Jewish Theological Seminary of America faculty +Rabbis from Cincinnati +Rabbis from Warsaw +Philosophers of Judaism +Philosophers of religion +Polish emigrants to the United States +Polish ethicists +Selma to Montgomery marches +Activists from Ohio +Jewish poets +Yiddish-language poets +Participants in the Second Vatican Council +Jewish American writers +Jewish ethicists +American Jewish anti-racism activists +American anti–Vietnam War activists +Jewish emigrants from Nazi Germany to the United States +African American–Jewish relations +20th-century American philosophers +20th-century American rabbis +20th-century Polish philosophers +Hochschule für die Wissenschaft des Judentums alumni +The Aberdeen Bestiary (Aberdeen University Library, Univ Lib. MS 24) is a 12th-century English illuminated manuscript bestiary that was first listed in 1542 in the inventory of the Old Royal Library at the Palace of Westminster. Due to similarities, it is often considered to be the "sister" manuscript of the Ashmole Bestiary. The connection between the ancient Greek didactic text Physiologus and similar bestiary manuscripts is also often noted. Information about the manuscript's origins and patrons are circumstantial, although the manuscript most likely originated from the 13th century and was owned by a wealthy ecclesiastical patron from north or south England. Currently, the Aberdeen Bestiary resides in the Aberdeen University Library in Scotland. + +History +The Aberdeen Bestiary and the Ashmole Bestiary are considered by Xenia Muratova, a professor of art history, to be "the work of different artists belonging to the same artistic milieu." Due to their "striking similarities" they are often compared and described by scholars as being "sister manuscripts." The medievalist scholar M. R. James considered the Aberdeen Bestiary ''a replica of Ashmole 1511" a view echoed by many other art historians. + +Provenance +The original patron of both the Aberdeen and Ashmole Bestiary was considered to be a high-ranking member of society such as a prince, king or another high ranking church official or monastery. However, since the section related to monastery life that was commonly depicted within the Aviarium manuscript was missing the original patron remains uncertain but it appears less likely to be a church member. The Aberdeen Bestiary was kept in Church and monastic settings for a majority of its history. However at some point it entered into the English royal collections library. The royal Westminster Library shelf stamp of King Henry the VIII is stamped on the side of the bestiary. How King Henry acquired the manuscript remains unknown although it was probably taken from a monastery. The manuscript appears to have been well-read by the family based on the amount of reading wear on the edges of the pages. Around the time King James of Scotland became the King of England the bestiary was passed along to the Marischal College, Aberdeen. The manuscript is in fragmented condition as many illuminations on folios were removed individually as miniatures likely not for monetary but possibly for personal reasons. The manuscript currently is in the Aberdeen Library in Scotland where it has remained since 1542. + +Description + +Materials +The Aberdeen bestiary is a gilded decorated manuscript featuring large miniatures and some of the finest pigment, parchment and gold leaf from its time. Some portions of the manuscript such as folio eight recto even feature tarnished silver leaf. The original patron was wealthy enough to afford such materials so that the artists and scribes could enjoy creative freedom while creating the manuscripts. The artists were professionally trained and experimented with new techniques - such as heavy washes mixed with light washes and dark thick lines and use of contrasting color. The aqua color that is in the Aberdeen Bestiary is not present in the Ashmole Bestiary. The Aberdeen manuscript is loaded with filigree flora design and champie style gold leaf initials. Canterbury is considered to be the original location of manufacture as the location was well known for manufacturing high-end luxury books during the thirteen century. Its similarities with the Canterbury Paris Psalter tree style also further draws evidence of this relation. + +Style +The craftsmanship of both Ashmole and Aberdeen bestiary suggest similar artists and scribes. Both the Ashmole and Aberdeen bestiary were probably made within 10 years of each other due to their stylistic and material similarities and the fact that both are crafted with the finest materials of their time. Stylistically both manuscripts are very similar but the Aberdeen has figures that are both more voluminous and less energetic than those of the Ashmole Bestiary. The color usage has been suggested as potentially Biblical in meaning as color usage had different interpretations in the early 13th century. The overall style of the human figures as well as color usage is very reminiscent of Roman mosaic art especially with the attention to detail in the drapery. Circles and ovals semi-realistically depict highlights throughout the manuscript. The way that animals are shaded in a Romanesque fashion with the use of bands to depict volume and form, which is similar to an earlier 12th-century Bury Bible made at Bury St.Edmunds. This Bestiary also shows stylistic similarities with the Paris Psalters of Canterbury. The Aviary section is similar to the Aviariium which is a well-known 12th century monastic text. The deviation from traditional color usage can be seen in the tiger, satyr, and unicorn folios as well as many other folios. The satyr in the Aberdeen Bestiary when compared to the satyr section of the slightly older Worksop bestiary is almost identical. There are small color notes in the Aberdeen Bestiary that are often seen in similar manuscripts dating between 1175 and 1250 which help indicate that it was made near the year 1200 or 1210. These notes are similar to many other side notes written on the sides of pages throughout the manuscript and were probably by the painter to remind himself of special circumstances, these note occur irregularly throughout the text. + +Illuminations +Folio page 1 to 3 recto depicts the Genesis 1:1-25 which is represented with a large full page illumination Biblical Creation scene in the manuscript. Folio 5 recto shows Adam, a large figure surrounded by gold leaf and towering over others, with the theme of 'Adam naming the animals' - this starts the compilation of the bestiary portion within the manuscript. Folio 5 verso depicts quadrupeds, livestock, wild beasts, and the concept of the herd. Folio 7 to 18 recto depicts large cats and other beasts such as wolves, foxes and dogs. Many pages from the start of the manuscript's bestiary section such as 11 verso featuring a hyena shows small pin holes which were likely used to map out and copy artwork to a new manuscript. Folio 20 verso to 28 recto depicts livestock such as sheep, horses, and goats. Small animals like cats and mice are depicted on folio 24 to 25. Pages 25 recto to 63 recto feature depictions of birds and folio 64 recto to 80 recto depicts reptiles, worms and fish. 77 recto to 91 verso depicts trees and plants and other elements of nature such as the nature of man. The end folios of the manuscript from 93 recto to 100 recto depicts the nature of stones and rocks. + +Seventeen of the Aberdeen manuscript pages are pricked for transfer in a process called pouncing such as clearly seen in the hyena folio as well as folio 3 recto and 3 verso depicting Genesis 1:26-1:28, 31, 1:1-2. The pricking must have been done shortly after the creation of the Adam and Eve folio pages since there is not damage done to nearby pages. Other pages used for pouncing include folio 7 recto to 18 verso which is the beginning of the beasts portion of the manuscript and likely depicted a lions as well as other big cats such as leopards, panthers and their characteristic as well as other large wild and domesticated beasts. + +Missing Folios +On folio 6 recto there was likely intended to be a depiction of a lion as in the Ashmole bestiary, but in this instance the pages were left blank although there are markings of margin lines. In comparison to the Ashmole bestiary, on 9 verso some leaves are missing which should have likely contained imagery of the antelope (Antalops), unicorn (Unicornis), lynx (Lynx), griffin (Gryps), part of elephant (Elephans). Near folio 21 verso two illuminations of the ox (Bos), camel (Camelus), dromedary (Dromedarius), ass (Asinus), onager (Onager) and part of horse (Equus) are also assumed to be missing. Also missing from folio 15 recto on are some leaves which should have contained crocodile (Crocodilus), manticore (Mantichora) and part of parandrus (Parandrus). These missing folios are assumed from comparisons between the Ashmole and other related bestiaries. + +Contents + + Folio 1 recto : Creation of heaven and earth (Genesis, 1: 1–5). (Full page) + Folio 1 verso: Creation of the waters and the firmament (Genesis, 1: 6–8) + Folio 2 recto : Creation of the birds and fishes (Genesis, 1: 20–23) + Folio 2 verso : Creation of the animals (Genesis, 1: 24–25) + Folio 3 recto : Creation of man (Genesis, 1: 26–28, 31; 2: 1–2) + Folio 5 recto : Adam names the animals (Isidore of Seville, Etymologiae, Book XII, i, 1–2) + Folio 5 verso : Animal (Animal) (Isidore of Seville, Etymologiae, Book XII, i, 3) + Folio 5 verso : Quadruped (Quadrupes) (Isidore of Seville, Etymologiae, Book XII, i, 4) + Folio 5 verso : Livestock (Pecus) (Isidore of Seville, Etymologiae, Book XII, i, 5–6) + Folio 5 verso : Beast of burden (Iumentum) (Isidore of Seville, Etymologiae, Book XII, i, 7) + Folio 5 verso : Herd (Armentum) (Isidore of Seville, Etymologiae, Book XII, i, 8) + +Beasts (Bestiae) + + Folio 7 recto : Lion (Leo) (Physiologus, Chapter 1; Isidore of Seville, Etymologiae, Book XII, ii, 3–6) + Folio 8 recto : Tiger (Tigris) (Isidore of Seville, Etymologiae, Book XII, ii, 7) + Folio 8 verso : Pard (Pard) (Isidore of Seville, Etymologiae, Book XII, ii, 10–11) + Folio 9 recto : Panther (Panther) (Physiologus, Chapter 16; Isidore of Seville, Etymologiae, Book XII, ii, 8–9) + Folio 10 recto : Elephant (Elephans) (Isidore of Seville, Etymologiae, Book XII, ii, 14; Physiologus, Chapter 43; Ambrose, Hexaemeron, Book VI, 35; Solinus, Collectanea rerum memorabilium, xxv, 1–7) + Folio 11 recto : Beaver (Castor) + Folio 11 recto : Ibex (Ibex) (Hugh of Fouilloy, II, 15) + Folio 11 verso : Hyena (Yena) (Physiologus, Chapter 24; Solinus, Collectanea rerum memorabilium, xxvii, 23–24) + Folio 12 recto : Crocotta (Crocotta) (Solinus, Collectanea rerum memorabilium, xxvii, 26) + Folio 12 recto : Bonnacon (Bonnacon) (Solinus, Collectanea rerum memorabilium, xl, 10–11) + Folio 12 verso : Ape (Simia) + Folio 13 recto : Satyr (Satyrs) + Folio 13 recto : Deer (Cervus) + Folio 14 recto : Goat (Caper) + Folio 14 verso : Wild goat (Caprea) + Folio 15 recto : Monoceros (Monoceros) (Solinus, Collectanea rerum memorabilium, lii, 39–40) + Folio 15 recto : Bear (Ursus) + Folio 15 verso : Leucrota (Leucrota) (Solinus, Collectanea rerum memorabilium, lii, 34) + Folio 16 recto : Parandrus (Parandrus) (Solinus, Collectanea rerum memorabilium, xxx, 25) + Folio 16 recto : Fox (Vulpes) + Folio 16 verso : Yale (Eale) (Solinus, Collectanea rerum memorabilium, lii, 35) + Folio 16 verso : Wolf (Lupus) + Folio 18 recto : Dog (Canis) + +Livestock (Pecora) + + Folio 20 verso : Sheep (Ovis) (Isidore of Seville, Etymologiae, Book XII, i, 9; Ambrose, Hexaemeron, Book VI, 20) + Folio 21 recto : Wether (Vervex) (Isidore of Seville, Etymologiae, Book XII, i, 10) + Folio 21 recto : Ram (Aries) (Isidore of Seville, Etymologiae, Book XII, i, 11) + Folio 21 recto : Lamb (Agnus) (Isidore of Seville, Etymologiae, Book XII, i, 12; Ambrose, Hexaemeron, Book VI, 28) + Folio 21 recto : He-goat (Hircus) (Isidore of Seville, Etymologiae, Book XII, i, 14) + Folio 21 verso : Kid (Hedus) (Isidore of Seville, Etymologiae, Book XII, i, 13) + Folio 21 verso : Boar (Aper) (Isidore of Seville, Etymologiae, Book XII, i, 27) + Folio 21 verso : Bullock (Iuvencus) (Isidore of Seville, Etymologiae, Book XII, i, 28) + Folio 21 verso : Bull (Taurus) (Isidore of Seville, Etymologiae, Book XII, i, 29) + Folio 22 recto : Horse (Equus) (Isidore of Seville, Etymologiae, Book XII, i, 41–56; Hugh of Fouilloy, III, xxiii) + Folio 23 recto : Mule (Mulus) (Isidore of Seville, Etymologiae, Book XII, i, 57–60) + +Small animals (Minuta animala) + + Folio 23 verso : Cat (Musio) (Isidore of Seville, Etymologiae, Book XII, ii, 38) + Folio 23 verso : Mouse (Mus) (Isidore of Seville, Etymologiae, Book XII, iii, 1) + Folio 23 verso : Weasel (Mustela) (Isidore of Seville, Etymologiae, Book XII, iii, 2; Physiologus, Chapter 21) + Folio 24 recto : Mole (Talpa) (Isidore of Seville, Etymologiae, Book XII, iii, 5) + Folio 24 recto : Hedgehog (Ericius) (Isidore of Seville, Etymologiae, Book XII, iii, 7; Ambrose, Hexaemeron, VI, 20) + Folio 24 verso : Ant (Formica) (Physiologus, 12; Ambrose, Hexaemeron, Book VI, 16, 20) + +Birds (Aves) + + Folio 25 recto : Bird (Avis) + Folio 25 verso : Dove (Columba) + Folio 26 recto : Dove and hawk (Columba et Accipiter) + Folio 26 verso : Dove (Columba) + Folio 29 verso : North wind and South wind (Aquilo et Auster ventus) + Folio 30 recto : Hawk (Accipiter) + Folio 31 recto : Turtle dove (Turtur) + Folio 32 verso : Palm tree (Palma) + Folio 33 verso : Cedar (Cedrus) + Folio 34 verso : Pelican (Pellicanus) - Orange and blue + Folio 35 verso : Night heron (Nicticorax) + Folio 36 recto : Hoopoe (Epops) + Folio 36 verso : Magpie (Pica) + Folio 37 recto : Raven (Corvus) + Folio 38 verso : Cock (Gallus) + Folio 41 recto : Ostrich (Strutio) + Folio 44 recto : Vulture (Vultur) + Folio 45 verso : Crane (Grus) + Folio 46 verso : Kite (Milvus) + Folio 46 verso : Parrot (Psitacus) + Folio 47 recto : Ibis (Ibis) + Folio 47 verso : Swallow (Yrundo) + Folio 48 verso : Stork (Ciconia) + Folio 49 verso : Blackbird (Merula) + Folio 50 recto : Eagle-owl (Bubo) + Folio 50 verso : Hoopoe (Hupupa) + Folio 51 recto : Little owl (Noctua) + Folio 51 recto : Bat (Vespertilio) + Folio 51 verso : Jay (Gragulus) + Folio 52 verso : Nightingale (Lucinia) + Folio 53 recto : Goose (Anser) + Folio 53 verso : Heron (Ardea) + Folio 54 recto : Partridge (Perdix) + Folio 54 verso : Halcyon (Alcyon) + Folio 55 recto : Coot (Fulica) + Folio 55 recto : Phoenix (Fenix) + Folio 56 verso : Caladrius (Caladrius) + Folio 57 verso : Quail (Coturnix) + Folio 58 recto : Crow (Cornix) + Folio 58 verso : Swan (Cignus) + Folio 59 recto : Duck (Anas) + Folio 59 verso : Peacock (Pavo) + Folio 61 recto : Eagle (Aquila) + Folio 63 recto : Bee (Apis) + +Snakes and Reptiles (Serpentes) + + Folio 64 verso : Perindens tree (Perindens) + Folio 65 verso : Snake (Serpens) + Folio 65 verso : Dragon (Draco) + Folio 66 recto : Basilisk (Basiliscus) + Folio 66 verso : Regulus (Regulus) + Folio 66 verso : Viper (Vipera) + Folio 67 verso : Asp (Aspis) + Folio 68 verso : Scitalis (Scitalis) + Folio 68 verso : Amphisbaena (Anphivena) + Folio 68 verso : Hydrus (Ydrus) + Folio 69 recto : Boa (Boa) + Folio 69 recto : Iaculus (Iaculus) + Folio 69 verso : Siren (Siren) + Folio 69 verso : Seps (Seps) + Folio 69 verso : Dipsa (Dipsa) + Folio 69 verso : Lizard (Lacertus) + Folio 69 verso : Salamander (Salamandra) + Folio 70 recto : Saura (Saura) + Folio 70 verso : Newt (Stellio) + Folio 71 recto : Of the nature of Snakes (De natura serpentium) + +Worms (Vermes) + + Folio 72 recto : Worms (Vermis) + +Fish (Pisces) + + Folio 72 verso : Fish (Piscis) + Folio 73 recto : Whale (Balena) + Folio 73 recto : Serra (Serra) + Folio 73 recto : Dolphin (Delphinus) + Folio 73 verso : Sea-pig (Porcus marinus) + Folio 73 verso : Crocodile (Crocodrillus) + Folio 73 verso : Mullet (Mullus) + Folio 74 recto : Fish (Piscis) + +Trees and Plants (Arbories) + + Folio 77 verso : Tree (Arbor) + Folio 78 verso : Fig (Ficus) + Folio 79 recto : Again of trees (Item de arboribus) + Folio 79 recto : Mulberry + Folio 79 recto : Sycamore + Folio 79 recto : Hazel + Folio 79 recto : Nuts + Folio 79 recto : Almond + Folio 79 recto : Chestnut + Folio 79 recto : Oak + Folio 79 verso : Beech + Folio 79 verso : Carob + Folio 79 verso : Pistachio + Folio 79 verso : Pitch pine + Folio 79 verso : Pine + Folio 79 verso : Fir + Folio 79 verso : Cedar + Folio 80 recto : Cypress + Folio 80 recto : Juniper + Folio 80 recto : Plane + Folio 80 recto : Oak + Folio 80 recto : Ash + Folio 80 recto : Alder + Folio 80 verso : Elm + Folio 80 verso : Poplar + Folio 80 verso : Willow + Folio 80 verso : Osier + Folio 80 verso : Box + +Nature of Man (Natura hominis) + + Folio 80 verso : Isidorus on the nature of man (Ysidorus de natura hominis) + Folio 89 recto : Isidorus on the parts of man's body (Ysidorus de membris hominis) + Folio 91 recto : Of the age of man (De etate hominis) + +Stones (Lapides) + + Folio 93 verso : Fire-bearing stone (Lapis ignifer) + Folio 94 verso : Adamas stone (Lapis adamas) + Folio 96 recto : Myrmecoleon (Mermecoleon) + Folio 96 verso : Verse (Versus) + Folio 97 recto : Stone in the foundation of the wall (Lapis in fundamento muri) + Folio 97 recto : The first stone, Jasper + Folio 97 recto : The second stone, Sapphire + Folio 97 recto : The third stone, Chalcedony + Folio 97 verso : The fourth stone, Smaragdus + Folio 98 recto : The fifth stone, Sardonyx + Folio 98 recto : The sixth stone, Sard + Folio 98 verso : The seventh stone, Chrysolite + Folio 98 verso : The eighth stone, Beryl + Folio 99 recto : The ninth stone, Topaz + Folio 99 verso : The tenth stone, Chrysoprase + Folio 99 verso : The eleventh stone, Hyacinth + Folio 100 recto : The twelfth stone, Amethyst + Folio 100 recto : Of stones and what they can do (De effectu lapidum) + +Gallery + +See also + Bestiary + List of medieval bestiaries + Physiologus +Ashmole Bestiary +Paris Psalter +Aviarium + +References + +External links + + The Aberdeen Bestiary Project - University of Aberdeen, Online version of the bestiary. + David Badke, The Medieval Bestiary : Manuscript: Univ. Lib. MS 24 (Aberdeen Bestiary) + +Bestiaries +University of Aberdeen +12th-century illuminated manuscripts +Biology books +Works of unknown authorship +The Latin American Integration Association / Asociación Latinoamericana de Integración / Associação Latino-Americana de Integração (LAIA / ALADI) is an international and regional scope organization. It was created on 12 August 1980 by the 1980 Montevideo Treaty, replacing the Latin American Free Trade Association (LAFTA/ALALC). Currently, it has 13 member countries, and any of the Latin American States may apply for accession. + +Objectives +The development of the integration process developed within the framework of the ALADI aims at promoting the harmonious and balanced socio-economic development of the region, and its long-term objective is the gradual and progressive establishment of a Latin-American single market. + +Basic functions + Promotion and regulation of reciprocal trade + Economic complementation + Development of economic cooperation actions contributing to the markets extension. + +General principles + Pluralism in political and economic matters; + Progressive convergence of partial actions for the establishment of a Latin-American Common Market; + Flexibility; + Differential treatments based on the development level of the member countries; and + Multiple forms of trade agreements. + +Integration mechanisms +The ALADI promotes the establishment of an area of economic preferences within the region, in order to create a Latin-American common market, through three mechanisms: + A Regional Tariff Preference applied to goods from the member countries compared to tariffs in-force for third countries. + Regional Scope Agreements, those in which all member countries participate. + Partial Scope Agreements, those wherein two or more countries of the area participate. + +The Relatively Less Economically Developed Countries of the region (Bolivia, Ecuador and Paraguay) benefit from a preferential system, through the lists of markets opening offered by the countries in favor of the Relatively Less Economically Developed Countries; special programs of cooperation (business rounds, pre-investment, financing, technological support); and countervailing measures in favor of the land-locked countries, the full participation of such countries in the integration process is sought. +The ALADI includes in its legal structure the strongest sub-regional, plurilateral and bilateral integration agreements arising in growing numbers in the continent. As a result, the ALADI – as an institutional and legal framework or “umbrella” of the regional integration- develops actions in order to support and foster these efforts for the progressive establishment of a common economic space. + +Member states + +Accession of other Latin American countries + +The 1980 Montevideo Treaty is open to the accession of any Latin-American country. On 26 August 1999, the first accession to the 1980 Montevideo Treaty was executed, with the incorporation of the Republic of Cuba as a member country of the ALADI. On 10 May 2012, the Republic of Panama became the thirteenth member country of the ALADI. Likewise, the accession of the Republic of Nicaragua was accepted in the Sixteenth Meeting of the Council of Ministers (Resolution 75 (XVI)), held on 11 August 2011. + +Currently, Nicaragua moves towards the fulfillment of conditions for becoming a member country of the ALADI. + +The ALADI opens its field of actions for the rest of Latin America through multilateral links or partial agreements with other countries and integration areas of the continent (Article 25). The Latin-American Integration Association also contemplates the horizontal cooperation with other integration movements in the world and partial actions with third developing countries or their respective integration areas (Article 27). + +Institutional structure + +Council of Ministers of Foreign Affairs +The Council of Ministers is the supreme body of the ALADI, and adopts the decisions for the superior political management of the integration process. +It is constituted by the Ministers of Foreign Affairs of the member countries. Notwithstanding, when one of such member countries assigns the competence of the integration affairs to a different Minister or Secretary of State, the member countries may be represented, with full powers, by the respective Minister or Secretary. It is convened by the Committee of Representatives, meets and makes decisions with the presence of all the member countries. + +Evaluation and Convergence Conference +It is in charge, among others, of analyzing the functioning of the integration process in all its aspects, promoting the convergence of the partial scope agreements seeking their progressive multilateralization, and promoting greater scope actions as regards economic integration. It is made up of Plenipotentiaries of the member countries. + +Committee of Representatives +It is the permanent political body and negotiating forum of the ALADI, where all the initiatives for the fulfillment of the objectives established by the 1980 Montevideo Treaty are analyzed and agreed on. It is composed of a Permanent Representative of each member country with right to one vote and an Alternate Representative. It meets regularly every 15 days and its Resolutions are adopted by the affirmative vote of two thirds of the member countries. + +General Secretariat +It is the technical body of the ALADI, and it may propose, evaluate, study and manage for the fulfillment of the objectives of the ALADI. It is composed of technical and administrative personnel, and directed by a Secretary-General, who has the support of two Undersecretaries, elected for a three-year period, renewable for the same term. + +Secretaries general + + 1980–1984 Julio César Schupp (Paraguay) + 1984–1987 Juan José Real (Uruguay) + 1987–1990 Norberto Bertaina (Argentina) + 1990–1993 Jorge Luis Ordóñez (Colombia) + 1993–1999 Antônio José de Cerqueira Antunes (Brasil) + 2000–2005 Juan Francisco Rojas Penso (Venezuela) + 2005–2008 Didier Opertti (Uruguay) + 2008–2009 Bernardino Hugo Saguier-Caballero (Paraguay) + 2009–2011 José Félix Fernández Estigarribia (Paraguay) + 2011–2017 Carlos Álvarez (Argentina) + 2017– Alejandro de la Peña Navarrete (Mexico) + +See also + + Free trade + Free trade area + International trade + Central America Free Trade Agreement + Free Trade Area of the Americas + Latin American economy + Trade bloc + Mercosur + Andean Community of Nations + Union of South American Nations + Central American Integration System + Caribbean Community + Latin American Economic System + Latin American Parliament + PetroCaribe + +References + +Latin America +Trade blocs +United Nations General Assembly observers +Organizations based in Montevideo +Organizations established in 1980 +Palermo, Montevideo +International organizations based in the Americas +Aircraft spotting, or planespotting, is a hobby consisting of tracking the movement of aircraft, which is usually accomplished by photography or videography. Besides monitoring aircraft, planespotting enthusiasts (who are usually called planespotters) also record information regarding airports, air traffic control communications, airline routes, and more. + +History and evolution +Aviation enthusiasts have been watching airplanes and other aircraft since aviation began. However, as a hobby (distinct from active/wartime work), planespotting did not appear until the second half of the 20th century. + +During World War II and the subsequent Cold War some countries encouraged their citizens to become "planespotters" in an "observation corps" or similar public body for reasons of public security. Britain had the Royal Observer Corps which operated between 1925 and 1995. A journal called The Aeroplane Spotter was published in January 1940. The publication included a glossary that was refined in 2010 and published online. + +The development of technology and global resources enabled a revolution in plane-spotting. Point and shoot cameras, DSLRs & walkie talkies significantly changed the hobby. With the help of the internet, websites such as FlightAware and Flightradar24 have made it possible for spotters to track and locate specific aircraft from all across the world. Websites specifically for aircraft, such as airliners.net, and social networking services, such as Twitter, Facebook and Instagram, allow spotters to record their sightings and upload their photos or see pictures of aircraft spotted by other people worldwide. + +Techniques + +When spotting aircraft, observers generally notice the key attributes of an aircraft, such as a distinctive noise from its engine, the number of contrails it is producing, or its callsign. Observers can also assess the size of the aircraft and the number, type, and position of its engines. Another distinctive attribute is the position of wings relative to the fuselage and the degree to which they are swept rearwards. The wings may be above the fuselage, below it, or fixed at midpoint. The number of wings indicates whether it is a monoplane, biplane or triplane. The position of the tailplane relative to the fin(s) and the shape of the fin are other attributes. The configuration of the landing gear can be distinctive, as well as the size and shape of the cockpit and passenger windows along with the layout of emergency exits and doors. + +Other features include the speed, cockpit placement, colour scheme or special equipment that changes the silhouette of the aircraft. Taken together these traits will enable the identification of an aircraft. If the observer is familiar with the airfield being used by the aircraft and its normal traffic patterns, he or she is more likely to leap quickly to a decision about the aircraft's identity – they may have seen the same type of aircraft from the same angle many times. This is particularly prevalent if the aircraft spotter is spotting commercial aircraft, operated by airlines that have a limited fleet. + +Spotters use equipment such as ADS-B decoders to track the movements of aircraft. The two most famous devices used are the AirNav Systems RadarBox and Kinetic Avionics SBS series. Both of them read and process the radar data and show the movements on a computer screen. Another tool that spotters can use are apps such as FlightRadar24 or Flightaware, where they can look at arrival and departure schedules and track the location of aircraft that have their transponder on. Most of the decoders also allow the exporting of logs from a certain route or airport. + +Spotting styles + +Some spotters will note and compile the markings, a national insignia or airline livery or logo, a squadron badge or code letters in the case of a military aircraft. Published manuals allow more information to be deduced, such as the delivery date or the manufacturer's construction number. Camouflage markings differ, depending on the surroundings in which that aircraft is expected to operate. + +In general, most spotters attempt to see as many aircraft of a given type, a particular airline, or a particular subset of aircraft such as business jets, commercial airliners, military and/or general aviation aircraft. Some spotters attempt to see every airframe and are known as "frame spotters." Others are keen to see every registration worn by each aircraft. + +Ancillary activities might include listening-in to air traffic control transmissions (using radio scanners, where that is legal), liaising with other "spotters" to clear up uncertainties as to what aircraft have been seen at specific times or in particular places. Several internet mailing list groups have been formed to help communicate aircraft seen at airports, queries and anomalies. These groups can cater to certain regions, certain aircraft types, or may appeal to a wider audience. The result is that information on aircraft movements can be delivered worldwide in a real-time fashion to spotters. + +The hobbyist might travel long distances to visit different airports, to see an unusual aircraft, or to view the remains of aircraft withdrawn from use. Air shows usually draw large numbers of spotters as they are opportunities to enter airfields and air bases worldwide that are usually closed to the public and to see displayed aircraft at close range. Some aircraft may be placed in the care of museums (see Aviation archaeology) – or perhaps be cannibalized in order to repair a similar aircraft already preserved. + +Aircraft registrations can be found in books, with online resources, or in monthly magazines from enthusiast groups. Most spotters maintained books of different aircraft fleets and would underline or check each aircraft seen. Each year, a revised version of the books would be published and the spotter would need to re-underline every aircraft seen. With the development of commercial aircraft databases spotters were finally able to record their sightings in an electronic database and produce reports that emulated the underlined books. + +Legal ramifications +The legal repercussions of the hobby were dramatically shown in November 2001 when fourteen aircraft spotters (twelve British, two Dutch) were arrested by Greek police after being observed at an open day at the Greek Air Force base at Kalamata. They were charged with espionage and faced a possible 20-year prison sentence if found guilty. After being held for six weeks, they were eventually released on $11,696 (£9,000) bail, and the charges reduced to the misdemeanor charge of illegal information collection. Confident of their innocence they returned for their trial in April, 2002 and were stunned to be found guilty, with eight of the group sentenced to three years, the rest for one year. At their appeal a year later, all were acquitted. + +As airport watch groups +In the wake of the targeting of airports by terrorists, enthusiasts' organisations and police in the UK have cooperated in creating a code of conduct for planespotters, in a similar vein to guidelines devised for train spotters. By asking enthusiasts to contact police if spotters believe they see or hear something suspicious, this is an attempt to allow enthusiasts to continue their hobby while increasing security around airports. Birmingham and Stansted pioneered this approach in Britain and prior to the 2012 London Olympics, RAF Northolt introduced a Flightwatch scheme based on the same cooperative principles. These changes are also being made abroad in countries such as Australia, where aviation enthusiasts are reporting suspicious or malicious actions to police. + +The organisation of such groups has now been echoed in parts of North America. For example, the Bensenville, Illinois police department have sponsored an Airport Watch group at the Chicago O'Hare Airport. Members are issued identification cards and given training to accurately record and report unusual activities around the airport perimeter. (Members are not permitted airside.) Meetings are attended and supported by the FBI, Chicago Department of Aviation and the TSA who also provide regular training to group members. The Bensenville program was modeled on similar programs in Toronto, Ottawa and Minneapolis. + +In 2009, a similar airport watch group was organized between airport security and local aircraft spotters at Montréal–Pierre Elliott Trudeau International Airport. As of 2016, the group has 46 members and a special phone number to use to contact police if suspicious activity is seen around the airport area. + +Extraordinary rendition +Following the events of 9/11, information collected by planespotters helped uncover what is known as extraordinary rendition by the CIA. Information on unusual movements of rendition aircraft provided data that was mapped by critical geographers such as Trevor Paglen and the Institute for Applied Autonomy. These data and maps led first to news reports and then to a number of governmental and inter-governmental investigations. + +See also + + Bus spotting + Car spotting + Train spotting + Satellite watching + +References + +External links + +SpottersWiki: The Ultimate Airport Spotting Guide +Airport Spotting Websites & Resources +Spotter Guide +JetPhotos (part of the Flightradar24) +Planespotters.net +Spotters.Aero (Ukrainian Spotter's Site) + +Aviation photography +Observation hobbies +Advertising is the practice and techniques employed to bring attention to a product or service. Advertising aims to put a product or service in the spotlight in hopes of drawing it attention from consumers. It is typically used to promote a specific good or service, but there are wide range of uses, the most common being the commercial advertisement. + +Commercial advertisements often seek to generate increased consumption of their products or services through "branding", which associates a product name or image with certain qualities in the minds of consumers. On the other hand, ads that intend to elicit an immediate sale are known as direct-response advertising. Non-commercial entities that advertise more than consumer products or services include political parties, interest groups, religious organizations and governmental agencies. Non-profit organizations may use free modes of persuasion, such as a public service announcement. Advertising may also help to reassure employees or shareholders that a company is viable or successful. + +In the 19th century, soap businesses were among the first to employ large-scale advertising campaigns. Thomas J. Barratt was hired by Pears to be its brand manager—the first of its kind—and in addition to creating slogans and images he recruited West End stage actress and socialite Lillie Langtry to become the poster-girl for Pears, making her the first celebrity to endorse a commercial product. Modern advertising originated with the techniques introduced with tobacco advertising in the 1920s, most significantly with the campaigns of Edward Bernays, considered the founder of modern, "Madison Avenue" advertising. + +Worldwide spending on advertising in 2015 amounted to an estimated . Advertising's projected distribution for 2017 was 40.4% on TV, 33.3% on digital, 9% on newspapers, 6.9% on magazines, 5.8% on outdoor and 4.3% on radio. Internationally, the largest ("Big Five") advertising agency groups are Omnicom, WPP, Publicis, Interpublic, and Dentsu. + +In Latin, advertere means "to turn towards". + +History + +Egyptians used papyrus to make sales messages and wall posters. Commercial messages and political campaign displays have been found in the ruins of Pompeii and ancient Arabia. Lost and found advertising on papyrus was common in ancient Greece and ancient Rome. Wall or rock painting for commercial advertising is another manifestation of an ancient advertising form, which is present to this day in many parts of Asia, Africa, and South America. The tradition of wall painting can be traced back to Indian rock art paintings that date back to 4000 BC. + +In ancient China, the earliest advertising known was oral, as recorded in the Classic of Poetry (11th to 7th centuries BC) of bamboo flutes played to sell confectionery. Advertisement usually takes in the form of calligraphic signboards and inked papers. A copper printing plate dated back to the Song dynasty used to print posters in the form of a square sheet of paper with a rabbit logo with "Jinan Liu's Fine Needle Shop" and "We buy high-quality steel rods and make fine-quality needles, to be ready for use at home in no time" written above and below is considered the world's earliest identified printed advertising medium. + +In Europe, as the towns and cities of the Middle Ages began to grow, and the general population was unable to read, instead of signs that read "cobbler", "miller", "tailor", or "blacksmith", images associated with their trade would be used such as a boot, a suit, a hat, a clock, a diamond, a horseshoe, a candle or even a bag of flour. Fruits and vegetables were sold in the city square from the backs of carts and wagons and their proprietors used street callers (town criers) to announce their whereabouts. The first compilation of such advertisements was gathered in "Les Crieries de Paris", a thirteenth-century poem by Guillaume de la Villeneuve. + +18th-19th century: Newspaper Advertising + +In the 18th century advertisements started to appear in weekly newspapers in England. These early print advertisements were used mainly to promote books and newspapers, which became increasingly affordable with advances in the printing press; and medicines, which were increasingly sought after. However, false advertising and so-called "quack" advertisements became a problem, which ushered in the regulation of advertising content. + +In the United States, newspapers grew quickly in the first few decades of the 19th century, in part due to advertising. By 1822, the United States had more newspaper readers than any other country. About half of the content of these newspapers consisted of advertising, usually local advertising, with half of the daily newspapers in the 1810s using the word "advertiser" in their name. + +In June 1836, French newspaper La Presse was the first to include paid advertising in its pages, allowing it to lower its price, extend its readership and increase its profitability and the formula was soon copied by all titles. Around 1840, Volney B. Palmer established the roots of the modern day advertising agency in Philadelphia. In 1842 Palmer bought large amounts of space in various newspapers at a discounted rate then resold the space at higher rates to advertisers. The actual ad – the copy, layout, and artwork – was still prepared by the company wishing to advertise; in effect, Palmer was a space broker. The situation changed when the first full-service advertising agency of N.W. Ayer & Son was founded in 1869 in Philadelphia. Ayer & Son offered to plan, create, and execute complete advertising campaigns for its customers. By 1900 the advertising agency had become the focal point of creative planning, and advertising was firmly established as a profession. + Around the same time, in France, Charles-Louis Havas extended the services of his news agency, Havas to include advertisement brokerage, making it the first French group to organize. At first, agencies were brokers for advertisement space in newspapers. + +Late 19th century: Modern Advertising + +Thomas J. Barratt of London has been called "the father of modern advertising". Working for the Pears soap company, Barratt created an effective advertising campaign for the company products, which involved the use of targeted slogans, images and phrases. One of his slogans, "Good morning. Have you used Pears' soap?" was famous in its day and into the 20th century. In 1882, Barratt recruited English actress and socialite Lillie Langtry to become the poster-girl for Pears, making her the first celebrity to endorse a commercial product. + +Becoming the company's brand manager in 1865, listed as the first of its kind by the Guinness Book of Records, Barratt introduced many of the crucial ideas that lie behind successful advertising and these were widely circulated in his day. He constantly stressed the importance of a strong and exclusive brand image for Pears and of emphasizing the product's availability through saturation campaigns. He also understood the importance of constantly reevaluating the market for changing tastes and mores, stating in 1907 that "tastes change, fashions change, and the advertiser has to change with them. An idea that was effective a generation ago would fall flat, stale, and unprofitable if presented to the public today. Not that the idea of today is always better than the older idea, but it is different – it hits the present taste." + +Enhanced advertising revenues was one effect of the Industrial Revolution in Britain. Thanks to the revolution and the consumers it created, by the mid-19th century biscuits and chocolate became products for the masses, and British biscuit manufacturers were among the first to introduce branding to distinguish grocery products. One the world's first global brands, Huntley & Palmers biscuits were sold in 172 countries in 1900, and their global reach was reflected in their advertisements. + +20th century + +As a result of massive industrialization, advertising increased dramatically in the United States. In 1919 it was 2.5 percent of gross domestic product (GDP) in the US, and it averaged 2.2 percent of GDP between then and at least 2007, though it may have declined dramatically since the Great Recession. + +Industry could not benefit from its increased productivity without a substantial increase in consumer spending. This contributed to the development of mass marketing designed to influence the population's economic behavior on a larger scale. In the 1910s and 1920s, advertisers in the U.S. adopted the doctrine that human instincts could be targeted and harnessed – "sublimated" into the desire to purchase commodities. Edward Bernays, a nephew of Sigmund Freud, became associated with the method and is sometimes called the founder of modern advertising and public relations. Bernays claimed that:In other words, selling products by appealing to the rational minds of customers (the main method used prior to Bernays) was much less effective than selling products based on the unconscious desires that Bernays felt were the true motivators of human action. "Sex sells" became a controversial issue, with techniques for titillating and enlarging the audience posing a challenge to conventional morality. + +In the 1920s, under Secretary of Commerce Herbert Hoover, the American government promoted advertising. Hoover himself delivered an address to the Associated Advertising Clubs of the World in 1925 called 'Advertising Is a Vital Force in Our National Life." In October 1929, the head of the U.S. Bureau of Foreign and Domestic Commerce, Julius Klein, stated "Advertising is the key to world prosperity." This was part of the "unparalleled" collaboration between business and government in the 1920s, according to a 1933 European economic journal. + +The tobacco companies became major advertisers in order to sell packaged cigarettes. The tobacco companies pioneered the new advertising techniques when they hired Bernays to create positive associations with tobacco smoking. + +Advertising was also used as a vehicle for cultural assimilation, encouraging workers to exchange their traditional habits and community structure in favor of a shared "modern" lifestyle. An important tool for influencing immigrant workers was the American Association of Foreign Language Newspapers (AAFLN). The AAFLN was primarily an advertising agency but also gained heavily centralized control over much of the immigrant press. + +At the turn of the 20th century, advertising was one of the few career choices for women. Since women were responsible for most household purchasing done, advertisers and agencies recognized the value of women's insight during the creative process. In fact, the first American advertising to use a sexual sell was created by a woman – for a soap product. Although tame by today's standards, the advertisement featured a couple with the message "A skin you love to touch". + +In the 1920s, psychologists Walter D. Scott and John B. Watson contributed applied psychological theory to the field of advertising. Scott said, "Man has been called the reasoning animal but he could with greater truthfulness be called the creature of suggestion. He is reasonable, but he is to a greater extent suggestible". He demonstrated this through his advertising technique of a direct command to the consumer. + +Radio from the 1920s + +In the early 1920s, the first radio stations were established by radio equipment manufacturers, followed by non-profit organizations such as schools, clubs and civic groups who also set up their own stations. Retailer and consumer goods manufacturers quickly recognized radio's potential to reach consumers in their home and soon adopted advertising techniques that would allow their messages to stand out; slogans, mascots, and jingles began to appear on radio in the 1920s and early television in the 1930s. + +The rise of mass media communications allowed manufacturers of branded goods to bypass retailers by advertising directly to consumers. This was a major paradigm shift which forced manufacturers to focus on the brand and stimulated the need for superior insights into consumer purchasing, consumption and usage behaviour; their needs, wants and aspirations. The earliest radio drama series were sponsored by soap manufacturers and the genre became known as a soap opera. Before long, radio station owners realized they could increase advertising revenue by selling 'air-time' in small time allocations which could be sold to multiple businesses. By the 1930s, these advertising spots, as the packets of time became known, were being sold by the station's geographical sales representatives, ushering in an era of national radio advertising. + +By the 1940s, manufacturers began to recognize the way in which consumers were developing personal relationships with their brands in a social/psychological/anthropological sense. Advertisers began to use motivational research and consumer research to gather insights into consumer purchasing. Strong branded campaigns for Chrysler and Exxon/Esso, using insights drawn research methods from psychology and cultural anthropology, led to some of the most enduring campaigns of the 20th century. + +Commercial television in the 1950s +In the early 1950s, the DuMont Television Network began the modern practice of selling advertisement time to multiple sponsors. Previously, DuMont had trouble finding sponsors for many of their programs and compensated by selling smaller blocks of advertising time to several businesses. This eventually became the standard for the commercial television industry in the United States. However, it was still a common practice to have single sponsor shows, such as The United States Steel Hour. In some instances the sponsors exercised great control over the content of the show – up to and including having one's advertising agency actually writing the show. The single sponsor model is much less prevalent now, a notable exception being the Hallmark Hall of Fame. + +Cable television from the 1980s +The late 1980s and early 1990s saw the introduction of cable television and particularly MTV. Pioneering the concept of the music video, MTV ushered in a new type of advertising: the consumer tunes in for the advertising message, rather than it being a by-product or afterthought. As cable and satellite television became increasingly prevalent, specialty channels emerged, including channels entirely devoted to advertising, such as QVC, Home Shopping Network, and ShopTV Canada. + +Internet from the 1990s + +With the advent of the ad server, online advertising grew, contributing to the "dot-com" boom of the 1990s. Entire corporations operated solely on advertising revenue, offering everything from coupons to free Internet access. At the turn of the 21st century, some websites, including the search engine Google, changed online advertising by personalizing ads based on web browsing behavior. This has led to other similar efforts and an increase in interactive advertising. + +The share of advertising spending relative to GDP has changed little across large changes in media since 1925. In 1925, the main advertising media in America were newspapers, magazines, signs on streetcars, and outdoor posters. Advertising spending as a share of GDP was about 2.9 percent. By 1998, television and radio had become major advertising media; by 2017, the balance between broadcast and online advertising had shifted, with online spending exceeding broadcast. Nonetheless, advertising spending as a share of GDP was slightly lower – about 2.4 percent. + +Guerrilla marketing involves unusual approaches such as staged encounters in public places, giveaways of products such as cars that are covered with brand messages, and interactive advertising where the viewer can respond to become part of the advertising message. This type of advertising is unpredictable, which causes consumers to buy the product or idea. This reflects an increasing trend of interactive and "embedded" ads, such as via product placement, having consumers vote through text messages, and various campaigns utilizing social network services such as Facebook or Twitter. + +The advertising business model has also been adapted in recent years. In media for equity, advertising is not sold, but provided to start-up companies in return for equity. If the company grows and is sold, the media companies receive cash for their shares. + +Domain name registrants (usually those who register and renew domains as an investment) sometimes "park" their domains and allow advertising companies to place ads on their sites in return for per-click payments. These ads are typically driven by pay per click search engines like Google or Yahoo, but ads can sometimes be placed directly on targeted domain names through a domain lease or by making contact with the registrant of a domain name that describes a product. Domain name registrants are generally easy to identify through WHOIS records that are publicly available at registrar websites. + +Classification + +Advertising may be categorized in a variety of ways, including by style, target audience, geographic scope, medium, or purpose. For example, in print advertising, classification by style can include display advertising (ads with design elements sold by size) vs. classified advertising (ads without design elements sold by the word or line). Advertising may be local, national or global. An ad campaign may be directed toward consumers or to businesses. The purpose of an ad may be to raise awareness (brand advertising), or to elicit an immediate sale (direct response advertising). The term above the line (ATL) is used for advertising involving mass media; more targeted forms of advertising and promotion are referred to as below the line (BTL). The two terms date back to 1954 when Procter & Gamble began paying their advertising agencies differently from other promotional agencies. In the 2010s, as advertising technology developed, a new term, through the line (TTL) began to come into use, referring to integrated advertising campaigns. + +Traditional media +Virtually any medium can be used for advertising. Commercial advertising media can include wall paintings, billboards, street furniture components, printed flyers and rack cards, radio, cinema and television adverts, web banners, mobile telephone screens, shopping carts, web popups, skywriting, bus stop benches, human billboards and forehead advertising, magazines, newspapers, town criers, sides of buses, banners attached to or sides of airplanes ("logojets"), in-flight advertisements on seatback tray tables or overhead storage bins, taxicab doors, roof mounts and passenger screens, musical stage shows, subway platforms and trains, elastic bands on disposable diapers, doors of bathroom stalls, stickers on apples in supermarkets, shopping cart handles (grabertising), the opening section of streaming audio and video, posters, and the backs of event tickets and supermarket receipts. Any situation in which an "identified" sponsor pays to deliver their message through a medium is advertising. + +Television Television advertising is one of the most expensive types of advertising; networks charge large amounts for commercial airtime during popular events. The annual Super Bowl football game in the United States is known as the most prominent advertising event on television – with an audience of over 108 million and studies showing that 50% of those only tuned in to see the advertisements. During the 2014 edition of this game, the average thirty-second ad cost US$4 million, and $8 million was charged for a 60-second spot. Virtual advertisements may be inserted into regular programming through computer graphics. It is typically inserted into otherwise blank backdrops or used to replace local billboards that are not relevant to the remote broadcast audience. Virtual billboards may be inserted into the background where none exist in real-life. This technique is especially used in televised sporting events. Virtual product placement is also possible. An infomercial is a long-format television commercial, typically five minutes or longer. The name blends the words "information" and "commercial". The main objective in an infomercial is to create an impulse purchase, so that the target sees the presentation and then immediately buys the product through the advertised toll-free telephone number or website. Infomercials describe and often demonstrate products, and commonly have testimonials from customers and industry professionals. + +Radio Radio advertisements are broadcast as radio waves to the air from a transmitter to an antenna and a thus to a receiving device. Airtime is purchased from a station or network in exchange for airing the commercials. While radio has the limitation of being restricted to sound, proponents of radio advertising often cite this as an advantage. Radio is an expanding medium that can be found on air, and also online. According to Arbitron, radio has approximately 241.6 million weekly listeners, or more than 93 percent of the U.S. population. + +Online Online advertising is a form of promotion that uses the Internet and World Wide Web for the expressed purpose of delivering marketing messages to attract customers. Online ads are delivered by an ad server. Examples of online advertising include contextual ads that appear on search engine results pages, banner ads, in pay per click text ads, rich media ads, Social network advertising, online classified advertising, advertising networks and e-mail marketing, including e-mail spam. A newer form of online advertising is Native Ads; they go in a website's news feed and are supposed to improve user experience by being less intrusive. However, some people argue this practice is deceptive. + +Domain names Domain name advertising is most commonly done through pay per click web search engines, however, advertisers often lease space directly on domain names that generically describe their products. When an Internet user visits a website by typing a domain name directly into their web browser, this is known as "direct navigation", or "type in" web traffic. Although many Internet users search for ideas and products using search engines and mobile phones, a large number of users around the world still use the address bar. They will type a keyword into the address bar such as "geraniums" and add ".com" to the end of it. Sometimes they will do the same with ".org" or a country-code Top Level Domain (TLD such as ".co.uk" for the United Kingdom or ".ca" for Canada). When Internet users type in a generic keyword and add .com or another top-level domain (TLD) ending, it produces a targeted sales lead. Domain name advertising was originally developed by Oingo (later known as Applied Semantics), one of Google's early acquisitions. + +Product placements is when a product or brand is embedded in entertainment and media. For example, in a film, the main character can use an item or other of a definite brand, as in the movie Minority Report, where Tom Cruise's character John Anderton owns a phone with the Nokia logo clearly written in the top corner, or his watch engraved with the Bulgari logo. Another example of advertising in film is in I, Robot, where main character played by Will Smith mentions his Converse shoes several times, calling them "classics", because the film is set far in the future. I, Robot and Spaceballs also showcase futuristic cars with the Audi and Mercedes-Benz logos clearly displayed on the front of the vehicles. Cadillac chose to advertise in the movie The Matrix Reloaded, which as a result contained many scenes in which Cadillac cars were used. Similarly, product placement for Omega Watches, Ford, VAIO, BMW and Aston Martin cars are featured in recent James Bond films, most notably Casino Royale. In "Fantastic Four: Rise of the Silver Surfer", the main transport vehicle shows a large Dodge logo on the front. Blade Runner includes some of the most obvious product placement; the whole film stops to show a Coca-Cola billboard. + +Print Print advertising describes advertising in a printed medium such as a newspaper, magazine, or trade journal. This encompasses everything from media with a very broad readership base, such as a major national newspaper or magazine, to more narrowly targeted media such as local newspapers and trade journals on very specialized topics. One form of print advertising is classified advertising, which allows private individuals or companies to purchase a small, narrowly targeted ad paid by the word or line. Another form of print advertising is the display ad, which is generally a larger ad with design elements that typically run in an article section of a newspaper. + +Outdoor + +Billboards, also known as hoardings in some parts of the world, are large structures located in public places which display advertisements to passing pedestrians and motorists. Most often, they are located on main roads with a large amount of passing motor and pedestrian traffic; however, they can be placed in any location with large numbers of viewers, such as on mass transit vehicles and in stations, in shopping malls or office buildings, and in stadiums. The form known as street advertising first came to prominence in the UK by Street Advertising Services to create outdoor advertising on street furniture and pavements. Working with products such as Reverse Graffiti, air dancers and 3D pavement advertising, for getting brand messages out into public spaces. Sheltered outdoor advertising combines outdoor with indoor advertisement by placing large mobile, structures (tents) in public places on temporary bases. The large outer advertising space aims to exert a strong pull on the observer, the product is promoted indoors, where the creative decor can intensify the impression. Mobile billboards are generally vehicle mounted billboards or digital screens. These can be on dedicated vehicles built solely for carrying advertisements along routes preselected by clients, they can also be specially equipped cargo trucks or, in some cases, large banners strewn from planes. The billboards are often lighted; some being backlit, and others employing spotlights. Some billboard displays are static, while others change; for example, continuously or periodically rotating among a set of advertisements. Mobile displays are used for various situations in metropolitan areas throughout the world, including: target advertising, one-day and long-term campaigns, conventions, sporting events, store openings and similar promotional events, and big advertisements from smaller companies. + +Point-of-sale In-store advertising is any advertisement placed in a retail store. It includes placement of a product in visible locations in a store, such as at eye level, at the ends of aisles and near checkout counters (a.k.a. POP – point of purchase display), eye-catching displays promoting a specific product, and advertisements in such places as shopping carts and in-store video displays. + +Novelties Advertising printed on small tangible items such as coffee mugs, T-shirts, pens, bags, and such is known as novelty advertising. Some printers specialize in printing novelty items, which can then be distributed directly by the advertiser, or items may be distributed as part of a cross-promotion, such as ads on fast food containers. + +Celebrity endorsements Advertising in which a celebrity endorses a product or brand leverages celebrity power, fame, money, popularity to gain recognition for their products or to promote specific stores' or products. Advertisers often advertise their products, for example, when celebrities share their favorite products or wear clothes by specific brands or designers. Celebrities are often involved in advertising campaigns such as television or print adverts to advertise specific or general products. The use of celebrities to endorse a brand can have its downsides, however; one mistake by a celebrity can be detrimental to the public relations of a brand. For example, following his performance of eight gold medals at the 2008 Olympic Games in Beijing, China, swimmer Michael Phelps' contract with Kellogg's was terminated, as Kellogg's did not want to associate with him after he was photographed smoking marijuana. Celebrities such as Britney Spears have advertised for multiple products including Pepsi, Candies from Kohl's, Twister, NASCAR, and Toyota. + +Aerial Using aircraft, balloons or airships to create or display advertising media. Skywriting is a notable example. + +New media approaches +A new advertising approach is known as advanced advertising, which is data-driven advertising, using large quantities of data, precise measuring tools and precise targeting. Advanced advertising also makes it easier for companies which sell ad-space to attribute customer purchases to the ads they display or broadcast. + +Increasingly, other media are overtaking many of the "traditional" media such as television, radio and newspaper because of a shift toward the usage of the Internet for news and music as well as devices like digital video recorders (DVRs) such as TiVo. + +Online advertising began with unsolicited bulk e-mail advertising known as "e-mail spam". Spam has been a problem for e-mail users since 1978. As new online communication channels became available, advertising followed. The first banner ad appeared on the World Wide Web in 1994. Prices of Web-based advertising space are dependent on the "relevance" of the surrounding web content and the traffic that the website receives. + +In online display advertising, display ads generate awareness quickly. Unlike search, which requires someone to be aware of a need, display advertising can drive awareness of something new and without previous knowledge. Display works well for direct response. Display is not only used for generating awareness, it is used for direct response campaigns that link to a landing page with a clear 'call to action'. + +As the mobile phone became a new mass medium in 1998 when the first paid downloadable content appeared on mobile phones in Finland, mobile advertising followed, also first launched in Finland in 2000. By 2007 the value of mobile advertising had reached $2 billion and providers such as Admob delivered billions of mobile ads. + +More advanced mobile ads include banner ads, coupons, Multimedia Messaging Service picture and video messages, advergames and various engagement marketing campaigns. A particular feature driving mobile ads is the 2D barcode, which replaces the need to do any typing of web addresses, and uses the camera feature of modern phones to gain immediate access to web content. 83 percent of Japanese mobile phone users already are active users of 2D barcodes. + +Some companies have proposed placing messages or corporate logos on the side of booster rockets and the International Space Station. + +Unpaid advertising (also called "publicity advertising"), can include personal recommendations ("bring a friend", "sell it"), spreading buzz, or achieving the feat of equating a brand with a common noun (in the United States, "Xerox" = "photocopier", "Kleenex" = tissue, "Vaseline" = petroleum jelly, "Hoover" = vacuum cleaner, and "Band-Aid" = adhesive bandage). However, some companies oppose the use of their brand name to label an object. Equating a brand with a common noun also risks turning that brand into a generic trademark – turning it into a generic term which means that its legal protection as a trademark is lost. + +Early in its life, The CW aired short programming breaks called "Content Wraps", to advertise one company's product during an entire commercial break. The CW pioneered "content wraps" and some products featured were Herbal Essences, Crest, Guitar Hero II, CoverGirl, and Toyota. + +A new promotion concept has appeared, "ARvertising", advertising on augmented reality technology. + +Controversy exists on the effectiveness of subliminal advertising (see mind control), and the pervasiveness of mass messages (propaganda). + +Rise in new media + +With the Internet came many new advertising opportunities. Pop-up, Flash, banner, pop-under, advergaming, and email advertisements (all of which are often unwanted or spam in the case of email) are now commonplace. Particularly since the rise of "entertaining" advertising, some people may like an advertisement enough to wish to watch it later or show a friend. In general, the advertising community has not yet made this easy, although some have used the Internet to widely distribute their ads to anyone willing to see or hear them. In the last three quarters of 2009, mobile and Internet advertising grew by 18% and 9% respectively, while older media advertising saw declines: −10.1% (TV), −11.7% (radio), −14.8% (magazines) and −18.7% (newspapers). Between 2008 and 2014, U.S. newspapers lost more than half their print advertising revenue. + +Niche marketing +Another significant trend regarding future of advertising is the growing importance of the niche market using niche or targeted ads. Also brought about by the Internet and the theory of the long tail, advertisers will have an increasing ability to reach specific audiences. In the past, the most efficient way to deliver a message was to blanket the largest mass market audience possible. However, usage tracking, customer profiles and the growing popularity of niche content brought about by everything from blogs to social networking sites, provide advertisers with audiences that are smaller but much better defined, leading to ads that are more relevant to viewers and more effective for companies' marketing products. Among others, Comcast Spotlight is one such advertiser employing this method in their video on demand menus. These advertisements are targeted to a specific group and can be viewed by anyone wishing to find out more about a particular business or practice, from their home. This causes the viewer to become proactive and actually choose what advertisements they want to view. +Niche marketing could also be helped by bringing the issue of colour into advertisements. Different colours play major roles when it comes to marketing strategies, for example, seeing the blue can promote a sense of calmness and gives a sense of security which is why many social networks such as Facebook use blue in their logos. +Google AdSense is an example of niche marketing. Google calculates the primary purpose of a website and adjusts ads accordingly; it uses keywords on the page (or even in emails) to find the general ideas of topics disused and places ads that will most likely be clicked on by viewers of the email account or website visitors. + +Crowdsourcing + +The concept of crowdsourcing has given way to the trend of user-generated advertisements. User-generated ads are created by people, as opposed to an advertising agency or the company themselves, often resulting from brand sponsored advertising competitions. For the 2007 Super Bowl, the Frito-Lays division of PepsiCo held the "Crash the Super Bowl" contest, allowing people to create their own Doritos commercials. Chevrolet held a similar competition for their Tahoe line of SUVs. Due to the success of the Doritos user-generated ads in the 2007 Super Bowl, Frito-Lays relaunched the competition for the 2009 and 2010 Super Bowl. The resulting ads were among the most-watched and most-liked Super Bowl ads. In fact, the winning ad that aired in the 2009 Super Bowl was ranked by the USA Today Super Bowl Ad Meter as the top ad for the year while the winning ads that aired in the 2010 Super Bowl were found by Nielsen's BuzzMetrics to be the "most buzzed-about". Another example of companies using crowdsourcing successfully is the beverage company Jones Soda that encourages consumers to participate in the label design themselves. + +This trend has given rise to several online platforms that host user-generated advertising competitions on behalf of a company. Founded in 2007, Zooppa has launched ad competitions for brands such as Google, Nike, Hershey's, General Mills, Microsoft, NBC Universal, Zinio, and Mini Cooper. Crowdsourcing remains controversial, as the long-term impact on the advertising industry is still unclear. + +Globalization + +Advertising has gone through five major stages of development: domestic, export, international, multi-national, and global. For global advertisers, there are four, potentially competing, business objectives that must be balanced when developing worldwide advertising: building a brand while speaking with one voice, developing economies of scale in the creative process, maximising local effectiveness of ads, and increasing the company's speed of implementation. Born from the evolutionary stages of global marketing are the three primary and fundamentally different approaches to the development of global advertising executions: exporting executions, producing local executions, and importing ideas that travel. + +Advertising research is key to determining the success of an ad in any country or region. The ability to identify which elements and/or moments of an ad contribute to its success is how economies of scale are maximized. Once one knows what works in an ad, that idea or ideas can be imported by any other market. Market research measures, such as Flow of Attention, Flow of Emotion and branding moments provide insight into what is working in an ad in any country or region because the measures are based on the visual, not verbal, elements of the ad. + +Foreign public messaging + +Foreign governments, particularly those that own marketable commercial products or services, often promote their interests and positions through the advertising of those goods because the target audience is not only largely unaware of the forum as a vehicle for foreign messaging but also willing to receive the message while in a mental state of absorbing information from advertisements during television commercial breaks, while reading a periodical, or while passing by billboards in public spaces. A prime example of this messaging technique is advertising campaigns to promote international travel. While advertising foreign destinations and services may stem from the typical goal of increasing revenue by drawing more tourism, some travel campaigns carry the additional or alternative intended purpose of promoting good sentiments or improving existing ones among the target audience towards a given nation or region. It is common for advertising promoting foreign countries to be produced and distributed by the tourism ministries of those countries, so these ads often carry political statements and/or depictions of the foreign government's desired international public perception. Additionally, a wide range of foreign airlines and travel-related services which advertise separately from the destinations, themselves, are owned by their respective governments; examples include, though are not limited to, the Emirates airline (Dubai), Singapore Airlines (Singapore), Qatar Airways (Qatar), China Airlines (Taiwan/Republic of China), and Air China (People's Republic of China). By depicting their destinations, airlines, and other services in a favorable and pleasant light, countries market themselves to populations abroad in a manner that could mitigate prior public impressions. + +Diversification +In the realm of advertising agencies, continued industry diversification has seen observers note that "big global clients don't need big global agencies any more". This is reflected by the growth of non-traditional agencies in various global markets, such as Canadian business TAXI and SMART in Australia and has been referred to as "a revolution in the ad world". + +New technology + +The ability to record shows on digital video recorders (such as TiVo) allow watchers to record the programs for later viewing, enabling them to fast forward through commercials. Additionally, as more seasons of pre-recorded box sets are offered for sale of television programs; fewer people watch the shows on TV. However, the fact that these sets are sold, means the company will receive additional profits from these sets. + +To counter this effect, a variety of strategies have been employed. Many advertisers have opted for product placement on TV shows like Survivor. Other strategies include integrating advertising with internet-connected program guidess (EPGs), advertising on companion devices (like smartphones and tablets) during the show, and creating mobile apps for TV programs. Additionally, some like brands have opted for social television sponsorship. + +The emerging technology of drone displays has recently been used for advertising purposes. + +Education +In recent years there have been several media literacy initiatives, and more specifically concerning advertising, that seek to empower citizens in the face of media advertising campaigns. + +Advertising education has become popular with bachelor, master and doctorate degrees becoming available in the emphasis. A surge in advertising interest is typically attributed to the strong relationship advertising plays in cultural and technological changes, such as the advance of online social networking. A unique model for teaching advertising is the student-run advertising agency, where advertising students create campaigns for real companies. Organizations such as the American Advertising Federation establish companies with students to create these campaigns. + +Purposes +Advertising is at the front of delivering the proper message to customers and prospective customers. The purpose of advertising is to inform the consumers about their product and convince customers that a company's services or products are the best, enhance the image of the company, point out and create a need for products or services, demonstrate new uses for established products, announce new products and programs, reinforce the salespeople's individual messages, draw customers to the business, and to hold existing customers. + +Sales promotions and brand loyalty +Sales promotions are another way to advertise. Sales promotions are double purposed because they are used to gather information about what type of customers one draws in and where they are, and to jump start sales. Sales promotions include things like contests and games, sweepstakes, product giveaways, samples coupons, loyalty programs, and discounts. The ultimate goal of sales promotions is to stimulate potential customers to action. + +Criticisms + +While advertising can be seen as necessary for economic growth, it is not without social costs. Unsolicited commercial e-mail and other forms of spam have become so prevalent as to have become a major nuisance to users of these services, as well as being a financial burden on internet service providers. Advertising is increasingly invading public spaces, such as schools, which some critics argue is a form of child exploitation. This increasing difficulty in limiting exposure to specific audiences can result in negative backlash for advertisers. In tandem with these criticisms, the advertising industry has seen low approval rates in surveys and negative cultural portrayals. + +One of the most controversial criticisms of advertisement in the present day is that of the predominance of advertising of foods high in sugar, fat, and salt specifically to children. Critics claim that food advertisements targeting children are exploitive and are not sufficiently balanced with proper nutritional education to help children understand the consequences of their food choices. Additionally, children may not understand that they are being sold something, and are therefore more impressionable. Michelle Obama has criticized large food companies for advertising unhealthy foods largely towards children and has requested that food companies either limit their advertising to children or advertise foods that are more in line with dietary guidelines. The other criticisms include the change that are brought by those advertisements on the society and also the deceiving ads that are aired and published by the corporations. Cosmetic and health industry are the ones which exploited the highest and created reasons of concern. + +A 2021 study found that for more than 80% of brands, advertising had a negative return on investment. Unsolicited ads have been criticized as attention theft. + +Regulation +There have been increasing efforts to protect the public interest by regulating the content and the influence of advertising. Some examples include restrictions for advertising alcohol, tobacco or gambling imposed in many countries, as well as the bans around advertising to children, which exist in parts of Europe. Advertising regulation focuses heavily on the veracity of the claims and as such, there are often tighter restrictions placed around advertisements for food and healthcare products. + +The advertising industries within some countries rely less on laws and more on systems of self-regulation. Advertisers and the media agree on a code of advertising standards that they attempt to uphold. The general aim of such codes is to ensure that any advertising is 'legal, decent, honest and truthful'. Some self-regulatory organizations are funded by the industry, but remain independent, with the intent of upholding the standards or codes like the Advertising Standards Authority in the UK. + +In the UK, most forms of outdoor advertising such as the display of billboards is regulated by the UK Town and County Planning system. Currently, the display of an advertisement without consent from the Planning Authority is a criminal offense liable to a fine of £2,500 per offense. In the US, many communities believe that many forms of outdoor advertising blight the public realm. As long ago as the 1960s in the US, there were attempts to ban billboard advertising in the open countryside. Cities such as São Paulo have introduced an outright ban with London also having specific legislation to control unlawful displays. + +Some governments restrict the languages that can be used in advertisements, but advertisers may employ tricks to try avoiding them. In France for instance, advertisers sometimes print English words in bold and French translations in fine print to deal with Article 120 of the 1994 Toubon Law limiting the use of English. + +The advertising of pricing information is another topic of concern for governments. In the United States for instance, it is common for businesses to only mention the existence and amount of applicable taxes at a later stage of a transaction. In Canada and New Zealand, taxes can be listed as separate items, as long as they are quoted up-front. In most other countries, the advertised price must include all applicable taxes, enabling customers to easily know how much it will cost them. + +Theory + +Hierarchy-of-effects models + +Various competing models of hierarchies of effects attempt to provide a theoretical underpinning to advertising practice. + The model of Clow and Baack clarifies the objectives of an advertising campaign and for each individual advertisement. The model postulates six steps a buyer moves through when making a purchase: + Awareness + Knowledge + Liking + Preference + Conviction + Purchase + Means-end theory suggests that an advertisement should contain a message or means that leads the consumer to a desired end-state. + Leverage points aim to move the consumer from understanding a product's benefits to linking those benefits with personal values. + +Marketing mix + +The marketing mix was proposed by professor E. Jerome McCarthy in the 1960s. It consists of four basic elements called the "four Ps". Product is the first P representing the actual product. Price represents the process of determining the value of a product. Place represents the variables of getting the product to the consumer such as distribution channels, market coverage and movement organization. The last P stands for Promotion which is the process of reaching the target market and convincing them to buy the product. + +In the 1990s, the concept of four Cs was introduced as a more customer-driven replacement of four P's. There are two theories based on four Cs: Lauterborn's four Cs (consumer, cost, communication, convenience) + and Shimizu's four Cs (commodity, cost, communication, channel) in the 7Cs Compass Model (Co-marketing). Communications can include advertising, sales promotion, public relations, publicity, personal selling, corporate identity, internal communication, SNS, and MIS. + +Research + +Advertising research is a specialized form of research that works to improve the effectiveness and efficiency of advertising. It entails numerous forms of research which employ different methodologies. Advertising research includes pre-testing (also known as copy testing) and post-testing of ads and/or campaigns. + +Pre-testing includes a wide range of qualitative and quantitative techniques, including: focus groups, in-depth target audience interviews (one-on-one interviews), small-scale quantitative studies and physiological measurement. The goal of these investigations is to better understand how different groups respond to various messages and visual prompts, thereby providing an assessment of how well the advertisement meets its communications goals. + +Post-testing employs many of the same techniques as pre-testing, usually with a focus on understanding the change in awareness or attitude attributable to the advertisement. With the emergence of digital advertising technologies, many firms have begun to continuously post-test ads using real-time data. This may take the form of A/B split-testing or multivariate testing. + +Continuous ad tracking and the Communicus System are competing examples of post-testing advertising research types. + +Semiotics + +Meanings between consumers and marketers depict signs and symbols that are encoded in everyday objects. Semiotics is the study of signs and how they are interpreted. Advertising has many hidden signs and meanings within brand names, logos, package designs, print advertisements, and television advertisements. Semiotics aims to study and interpret the message being conveyed in (for example) advertisements. Logos and advertisements can be interpreted at two levels – known as the surface level and the underlying level. The surface level uses signs creatively to create an image or personality for a product. These signs can be images, words, fonts, colors, or slogans. The underlying level is made up of hidden meanings. The combination of images, words, colors, and slogans must be interpreted by the audience or consumer. The "key to advertising analysis" is the signifier and the signified. The signifier is the object and the signified is the mental concept. A product has a signifier and a signified. The signifier is the color, brand name, logo design, and technology. The signified has two meanings known as denotative and connotative. The denotative meaning is the meaning of the product. A television's denotative meaning might be that it is high definition. The connotative meaning is the product's deep and hidden meaning. A connotative meaning of a television would be that it is top-of-the-line. + +Apple's commercials used a black silhouette of a person that was the age of Apple's target market. They placed the silhouette in front of a blue screen so that the picture behind the silhouette could be constantly changing. However, the one thing that stays the same in these ads is that there is music in the background and the silhouette is listening to that music on a white iPod through white headphones. Through advertising, the white color on a set of earphones now signifies that the music device is an iPod. The white color signifies almost all of Apple's products. + +The semiotics of gender plays a key influence on the way in which signs are interpreted. When considering gender roles in advertising, individuals are influenced by three categories. Certain characteristics of stimuli may enhance or decrease the elaboration of the message (if the product is perceived as feminine or masculine). Second, the characteristics of individuals can affect attention and elaboration of the message (traditional or non-traditional gender role orientation). Lastly, situational factors may be important to influence the elaboration of the message. + +There are two types of marketing communication claims-objective and subjective. Objective claims stem from the extent to which the claim associates the brand with a tangible product or service feature. For instance, a camera may have auto-focus features. Subjective claims convey emotional, subjective, impressions of intangible aspects of a product or service. They are non-physical features of a product or service that cannot be directly perceived, as they have no physical reality. For instance the brochure has a beautiful design. Males tend to respond better to objective marketing-communications claims while females tend to respond better to subjective marketing communications claims. + +Voiceovers are commonly used in advertising. Most voiceovers are done by men, with figures of up to 94% having been reported. There have been more female voiceovers in recent years, but mainly for food, household products, and feminine-care products. + +Gender effects on comprehension +According to a 1977 study by David Statt, females process information comprehensively, while males process information through heuristic devices such as procedures, methods or strategies for solving problems, which could have an effect on how they interpret advertising. According to this study, men prefer to have available and apparent cues to interpret the message, whereas females engage in more creative, associative, imagery-laced interpretation. Later research by a Danish team found that advertising attempts to persuade men to improve their appearance or performance, whereas its approach to women aims at transformation toward an impossible ideal of female presentation. In Paul Suggett's article "The Objectification of Women in Advertising" he discusses the negative impact that these women in advertisements, who are too perfect to be real, have on women, as well as men, in real life. Advertising's manipulation of women's aspiration to these ideal types as portrayed in film, in erotic art, in advertising, on stage, within music videos and through other media exposures requires at least a conditioned rejection of female reality and thereby takes on a highly ideological cast. Studies show that these expectations of women and young girls negatively affect their views about their bodies and appearances. These advertisements are directed towards men. Not everyone agrees: one critic viewed this monologic, gender-specific interpretation of advertising as excessively skewed and politicized. There are some companies like Dove and aerie that are creating commercials to portray more natural women, with less post production manipulation, so more women and young girls are able to relate to them. + +More recent research by Martin (2003) reveals that males and females differ in how they react to advertising depending on their mood at the time of exposure to the ads and on the affective tone of the advertising. When feeling sad, males prefer happy ads to boost their mood. In contrast, females prefer happy ads when they are feeling happy. The television programs in which ads are embedded influence a viewer's mood state. Susan Wojcicki, author of the article "Ads that Empower Women don't just Break Stereotypes—They're also Effective" discusses how advertising to women has changed since the first Barbie commercial, where a little girl tells the doll that, she wants to be just like her. Little girls grow up watching advertisements of scantily clad women advertising things from trucks to burgers and Wojcicki states that this shows girls that they are either arm candy or eye candy. + +Alternatives +Other approaches to revenue include donations, paid subscriptions, microtransactions, and data monetization. Websites and applications are "ad-free" when not using advertisements at all for revenue. For example, the online encyclopaedia Wikipedia provides free content by receiving funding from charitable donations. + +"Fathers" of advertising + Late 1700s – Benjamin Franklin (1706–1790) – "father of advertising in America" + Late 1800s – Thomas J. Barratt (1841–1914) of London – called "the father of modern advertising" by T.F.G. Coates + Early 1900s – J. Henry ("Slogan") Smythe, Jr of Philadelphia – "world's best known slogan writer" + Early 1900s – Albert Lasker (1880–1952) – the "father of modern advertising"; defined advertising as "salesmanship in print, driven by a reason why" + Mid-1900s – David Ogilvy (1911–1999) – advertising tycoon, founder of Ogilvy & Mather, known as the "father of advertising" + +Influential thinkers in advertising theory and practice + + N. W. Ayer & Son – probably the first advertising agency to use mass media (i.e. telegraph) in a promotional campaign + Claude C. Hopkins (1866–1932) – popularised the use of test campaigns, especially coupons in direct mail, to track the efficiency of marketing spend + Ernest Dichter (1907–1991) – developed the field of motivational research, used extensively in advertising + E. St. Elmo Lewis (1872–1948) – developed the first hierarchy of effects model (AIDA) used in sales and advertising + Arthur Nielsen (1897–1980) – founded one of the earliest international advertising agencies and developed ratings for radio & TV + David Ogilvy (1911–1999) – pioneered the positioning concept and advocated of the use of brand image in advertising + Charles Coolidge Parlin (1872–1942) – regarded as the pioneer of the use of marketing research in advertising + Rosser Reeves (1910–1984) – developed the concept of the unique selling proposition (USP) and advocated the use of repetition in advertising + Al Ries (1926–2022) – advertising executive, author and credited with coining the term "positioning" in the late 1960s + Daniel Starch (1883–1979) – developed the Starch score method of measuring print media effectiveness (still in use) + J Walter Thompson – one of the earliest advertising agencies + +See also + + Advertisements in schools + Advertorial + Annoyance factor + Bibliography of advertising + Branded content + Commercial speech + Comparative advertising + Conquesting + Copywriting + Demo mode + Direct-to-consumer advertising + Family in advertising + Graphic design + Gross rating point + History of Advertising Trust + Informative advertising + Integrated marketing communications + List of advertising awards + Local advertising + Market overhang + Media planning + Meta-advertising + Mobile marketing + Performance-based advertising + Promotional mix + Senior media creative + Shock advertising + Viral marketing + World Federation of Advertisers + +References +Notes + +Further reading + + Arens, William, and Michael Weigold. Contemporary Advertising: And Integrated Marketing Communications (2012) + Belch, George E., and Michael A. Belch. Advertising and Promotion: An Integrated Marketing Communications Perspective (10th ed. 2014) + Biocca, Frank. Television and Political Advertising: Volume I: Psychological Processes (Routledge, 2013) + Chandra, Ambarish, and Ulrich Kaiser. "Targeted advertising in magazine markets and the advent of the internet." Management Science 60.7 (2014) pp: 1829–1843. + Chen, Yongmin, and Chuan He. "Paid placement: Advertising and search on the internet*." The Economic Journal 121#556 (2011): F309–F328. online + Johnson-Cartee, Karen S., and Gary Copeland. Negative political advertising: Coming of age (2013) + McAllister, Matthew P. and Emily West, eds. HardcoverThe Routledge Companion to Advertising and Promotional Culture (2013) + McFall, Elizabeth Rose Advertising: a cultural economy (2004), cultural and sociological approaches to advertising + Moriarty, Sandra, and Nancy Mitchell. Advertising & IMC: Principles and Practice (10th ed. 2014) + Okorie, Nelson. The Principles of Advertising: concepts and trends in advertising (2011) + Reichert, Tom, and Jacqueline Lambiase, eds. Sex in advertising: Perspectives on the erotic appeal (Routledge, 2014) + Sheehan, Kim Bartel. Controversies in contemporary advertising (Sage Publications, 2013) + Vestergaard, Torben and Schrøder, Kim. The Language of Advertising. Oxford: Basil Blackwell, 1985. + Splendora, Anthony. "Discourse", a Review of Vestergaard and Schrøder, The Language of Advertising in Language in Society Vol. 15, No. 4 (Dec., 1986), pp. 445–449 + +History + + Brandt, Allan. The Cigarette Century (2009) + Crawford, Robert. But Wait, There's More!: A History of Australian Advertising, 1900–2000 (2008) + Ewen, Stuart. Captains of Consciousness: Advertising and the Social Roots of Consumer Culture. New York: McGraw-Hill, 1976. + Fox, Stephen R. The mirror makers: A history of American advertising and its creators (University of Illinois Press, 1984) + Friedman, Walter A. Birth of a Salesman (Harvard University Press, 2005), In the United States + Jacobson, Lisa. Raising consumers: Children and the American mass market in the early twentieth century (Columbia University Press, 2013) + Jamieson, Kathleen Hall. Packaging the presidency: A history and criticism of presidential campaign advertising (Oxford University Press, 1996) + Laird, Pamela Walker. Advertising progress: American business and the rise of consumer marketing (Johns Hopkins University Press, 2001.) + Lears, Jackson. Fables of abundance: A cultural history of advertising in America (1995) + Liguori, Maria Chiara. "North and South: Advertising Prosperity in the Italian Economic Boom Years." Advertising & Society Review (2015) 15#4 + Meyers, Cynthia B. A Word from Our Sponsor: Admen, Advertising, and the Golden Age of Radio (2014) + Mazzarella, William. Shoveling smoke: Advertising and globalization in contemporary India (Duke University Press, 2003) + Moriarty, Sandra, et al. Advertising: Principles and practice (Pearson Australia, 2014), Australian perspectives + Nevett, Terence R. Advertising in Britain: a history (1982) + Oram, Hugh. The advertising book: The history of advertising in Ireland (MOL Books, 1986) + Presbrey, Frank. "The history and development of advertising." Advertising & Society Review (2000) 1#1 online + Saunders, Thomas J. "Selling under the Swastika: Advertising and Commercial Culture in Nazi Germany." German History (2014): ghu058. + Short, John Phillip. "Advertising Empire: Race and Visual Culture in Imperial Germany." Enterprise and Society (2014): khu013. + Sivulka, Juliann. Soap, sex, and cigarettes: A cultural history of American advertising (Cengage Learning, 2011) + Spring, Dawn. "The Globalization of American Advertising and Brand Management: A Brief History of the J. Walter Thompson Company, Proctor and Gamble, and US Foreign Policy." Global Studies Journal (2013). 5#4 + Stephenson, Harry Edward, and Carlton McNaught. The Story of Advertising in Canada: A Chronicle of Fifty Years (Ryerson Press, 1940) + Tungate, Mark. Adland: a global history of advertising (Kogan Page Publishers, 2007.) + West, Darrell M. Air Wars: Television Advertising and Social Media in Election Campaigns, 1952–2012 (Sage, 2013) + +External links + + Hartman Center for Sales, Advertising & Marketing History at Duke University + Duke University Libraries Digital Collections: + Ad*Access, over 7,000 U.S. and Canadian advertisements, dated 1911–1955, includes World War II propaganda. + Emergence of Advertising in America, 9,000 advertising items and publications dating from 1850 to 1940, illustrating the rise of consumer culture and the birth of a professionalized advertising industry in the United States. + AdViews, vintage television commercials + ROAD 2.0, 30,000 outdoor advertising images + Medicine & Madison Avenue, documents advertising of medical and pharmaceutical products + Art & Copy, a 2009 documentary film about the advertising industry + + +Articles containing video clips +Communication design +Promotion and marketing communications +Business models +In the field of artificial intelligence, the most difficult problems are informally known as AI-complete or AI-hard, implying that the difficulty of these computational problems, assuming intelligence is computational, is equivalent to that of solving the central artificial intelligence problem—making computers as intelligent as people, or strong AI. To call a problem AI-complete reflects an attitude that it would not be solved by a simple specific algorithm. + +AI-complete problems are hypothesised to include computer vision, natural language understanding, and dealing with unexpected circumstances while solving any real-world problem. + +Currently, AI-complete problems cannot be solved with modern computer technology alone, but would also require human computation. This property could be useful, for example, to test for the presence of humans as CAPTCHAs aim to do, and for computer security to circumvent brute-force attacks. + +History +The term was coined by Fanya Montalvo by analogy with NP-complete and NP-hard in complexity theory, which formally describes the most famous class of difficult problems. Early uses of the term are in Erik Mueller's 1987 PhD dissertation and in Eric Raymond's 1991 Jargon File. + +AI-complete problems +AI-complete problems are hypothesized to include: + + AI peer review (composite natural language understanding, automated reasoning, automated theorem proving, formalized logic expert system) + Bongard problems + Computer vision (and subproblems such as object recognition) + Natural language understanding (and subproblems such as text mining, machine translation, and word-sense disambiguation) + Autonomous driving + Dealing with unexpected circumstances while solving any real world problem, whether it's navigation or planning or even the kind of reasoning done by expert systems. + +Machine translation + +To translate accurately, a machine must be able to understand the text. It must be able to follow the author's argument, so it must have some ability to reason. It must have extensive world knowledge so that it knows what is being discussed — it must at least be familiar with all the same commonsense facts that the average human translator knows. Some of this knowledge is in the form of facts that can be explicitly represented, but some knowledge is unconscious and closely tied to the human body: for example, the machine may need to understand how an ocean makes one feel to accurately translate a specific metaphor in the text. It must also model the authors' goals, intentions, and emotional states to accurately reproduce them in a new language. In short, the machine is required to have wide variety of human intellectual skills, including reason, commonsense knowledge and the intuitions that underlie motion and manipulation, perception, and social intelligence. Machine translation, therefore, is believed to be AI-complete: it may require strong AI to be done as well as humans can do it. + +Software brittleness + +Current AI systems can solve very simple and/or restricted versions of AI-complete problems, but never in their full generality. When AI researchers attempt to "scale up" their systems to handle more complicated, real-world situations, the programs tend to become excessively brittle without commonsense knowledge or a rudimentary understanding of the situation: they fail as unexpected circumstances outside of its original problem context begin to appear. When human beings are dealing with new situations in the world, they are helped immensely by the fact that they know what to expect: they know what all things around them are, why they are there, what they are likely to do and so on. They can recognize unusual situations and adjust accordingly. A machine without strong AI has no other skills to fall back on. + +DeepMind published a work in May 2022 in which they trained a single model to do several things at the same time. The model, named Gato, can "play Atari, caption images, chat, stack blocks with a real robot arm and much more, deciding based on its context whether to output text, joint torques, button presses, or other tokens." + +Formalization +Computational complexity theory deals with the relative computational difficulty of computable functions. By definition, it does not cover problems whose solution is unknown or has not been characterised formally. Since many AI problems have no formalisation yet, conventional complexity theory does not allow the definition of AI-completeness. + +To address this problem, a complexity theory for AI has been proposed. It is based on a model of computation that splits the computational burden between a computer and a human: one part is solved by computer and the other part solved by human. This is formalised by a human-assisted Turing machine. The formalisation defines algorithm complexity, problem complexity and reducibility which in turn allows equivalence classes to be defined. + +The complexity of executing an algorithm with a human-assisted Turing machine is given by a pair , where the first element represents the complexity of the human's part and the second element is the complexity of the machine's part. + +Results +The complexity of solving the following problems with a human-assisted Turing machine is: + + Optical character recognition for printed text: + Turing test: + for an -sentence conversation where the oracle remembers the conversation history (persistent oracle): + for an -sentence conversation where the conversation history must be retransmitted: + for an -sentence conversation where the conversation history must be retransmitted and the person takes linear time to read the query: + ESP game: + Image labelling (based on the Arthur–Merlin protocol): + Image classification: human only: , and with less reliance on the human: . + +See also + ASR-complete + List of unsolved problems in computer science + Synthetic intelligence + Practopoiesis + +References + +Artificial intelligence +Computational problems +Archaeoastronomy (also spelled archeoastronomy) is the interdisciplinary or multidisciplinary study of how people in the past "have understood the phenomena in the sky, how they used these phenomena and what role the sky played in their cultures". Clive Ruggles argues it is misleading to consider archaeoastronomy to be the study of ancient astronomy, as modern astronomy is a scientific discipline, while archaeoastronomy considers symbolically rich cultural interpretations of phenomena in the sky by other cultures. It is often twinned with ethnoastronomy, the anthropological study of skywatching in contemporary societies. Archaeoastronomy is also closely associated with historical astronomy, the use of historical records of heavenly events to answer astronomical problems and the history of astronomy, which uses written records to evaluate past astronomical practice. + +Archaeoastronomy uses a variety of methods to uncover evidence of past practices including archaeology, anthropology, astronomy, statistics and probability, and history. Because these methods are diverse and use data from such different sources, integrating them into a coherent argument has been a long-term difficulty for archaeoastronomers. Archaeoastronomy fills complementary niches in landscape archaeology and cognitive archaeology. Material evidence and its connection to the sky can reveal how a wider landscape can be integrated into beliefs about the cycles of nature, such as Mayan astronomy and its relationship with agriculture. Other examples which have brought together ideas of cognition and landscape include studies of the cosmic order embedded in the roads of settlements. + +Archaeoastronomy can be applied to all cultures and all time periods. The meanings of the sky vary from culture to culture; nevertheless there are scientific methods which can be applied across cultures when examining ancient beliefs. It is perhaps the need to balance the social and scientific aspects of archaeoastronomy which led Clive Ruggles to describe it as "a field with academic work of high quality at one end but uncontrolled speculation bordering on lunacy at the other". + +History + +Two hundred years before John Michell wrote the above, there were no archaeoastronomers and there were no professional archaeologists, but there were astronomers and antiquarians. Some of their works are considered precursors of archaeoastronomy; antiquarians interpreted the astronomical orientation of the ruins that dotted the English countryside as William Stukeley did of Stonehenge in 1740, while John Aubrey in 1678 and Henry Chauncy in 1700 sought similar astronomical principles underlying the orientation of churches. Late in the nineteenth century astronomers such as Richard Proctor and Charles Piazzi Smyth investigated the astronomical orientations of the pyramids. + +The term archaeoastronomy was advanced by Elizabeth Chesley Baity (following the suggestion of Euan MacKie) in 1973, but as a topic of study it may be much older, depending on how archaeoastronomy is defined. Clive Ruggles says that Heinrich Nissen, working in the mid-nineteenth century was arguably the first archaeoastronomer. Rolf Sinclair says that Norman Lockyer, working in the late 19th and early 20th centuries, could be called the 'father of archaeoastronomy'. Euan MacKie would place the origin even later, stating: "...the genesis and modern flowering of archaeoastronomy must surely lie in the work of Alexander Thom in Britain between the 1930s and the 1970s". + +In the 1960s the work of the engineer Alexander Thom and that of the astronomer Gerald Hawkins, who proposed that Stonehenge was a Neolithic computer, inspired new interest in the astronomical features of ancient sites. The claims of Hawkins were largely dismissed, but this was not the case for Alexander Thom's work, whose survey results of megalithic sites hypothesized widespread practice of accurate astronomy in the British Isles. Euan MacKie, recognizing that Thom's theories needed to be tested, excavated at the Kintraw standing stone site in Argyllshire in 1970 and 1971 to check whether the latter's prediction of an observation platform on the hill slope above the stone was correct. There was an artificial platform there and this apparent verification of Thom's long alignment hypothesis (Kintraw was diagnosed as an accurate winter solstice site) led him to check Thom's geometrical theories at the Cultoon stone circle in Islay, also with a positive result. MacKie therefore broadly accepted Thom's conclusions and published new prehistories of Britain. In contrast a re-evaluation of Thom's fieldwork by Clive Ruggles argued that Thom's claims of high accuracy astronomy were not fully supported by the evidence. Nevertheless, Thom's legacy remains strong, Edwin C. Krupp wrote in 1979, "Almost singlehandedly he has established the standards for archaeo-astronomical fieldwork and interpretation, and his amazing results have stirred controversy during the last three decades." His influence endures and practice of statistical testing of data remains one of the methods of archaeoastronomy. + +The approach in the New World, where anthropologists began to consider more fully the role of astronomy in Amerindian civilizations, was markedly different. They had access to sources that the prehistory of Europe lacks such as ethnographies and the historical records of the early colonizers. Following the pioneering example of Anthony Aveni, this allowed New World archaeoastronomers to make claims for motives which in the Old World would have been mere speculation. The concentration on historical data led to some claims of high accuracy that were comparatively weak when compared to the statistically led investigations in Europe. + +This came to a head at a meeting sponsored by the International Astronomical Union (IAU) in Oxford in 1981. The methodologies and research questions of the participants were considered so different that the conference proceedings were published as two volumes. Nevertheless, the conference was considered a success in bringing researchers together and Oxford conferences have continued every four or five years at locations around the world. The subsequent conferences have resulted in a move to more interdisciplinary approaches with researchers aiming to combine the contextuality of archaeological research, which broadly describes the state of archaeoastronomy today, rather than merely establishing the existence of ancient astronomies, archaeoastronomers seek to explain why people would have an interest in the night sky. + +Relations to other disciplines + +Archaeoastronomy has long been seen as an interdisciplinary field that uses written and unwritten evidence to study the astronomies of other cultures. As such, it can be seen as connecting other disciplinary approaches for investigating ancient astronomy: astroarchaeology (an obsolete term for studies that draw astronomical information from the alignments of ancient architecture and landscapes), history of astronomy (which deals primarily with the written textual evidence), and ethnoastronomy (which draws on the ethnohistorical record and contemporary ethnographic studies). + +Reflecting Archaeoastronomy's development as an interdisciplinary subject, research in the field is conducted by investigators trained in a wide range of disciplines. Authors of recent doctoral dissertations have described their work as concerned with the fields of archaeology and cultural anthropology; with various fields of history including the history of specific regions and periods, the history of science and the history of religion; and with the relation of astronomy to art, literature and religion. Only rarely did they describe their work as astronomical, and then only as a secondary category. + +Both practicing archaeoastronomers and observers of the discipline approach it from different perspectives. Other researchers relate archaeoastronomy to the history of science, either as it relates to a culture's observations of nature and the conceptual framework they devised to impose an order on those observations or as it relates to the political motives which drove particular historical actors to deploy certain astronomical concepts or techniques. Art historian Richard Poss took a more flexible approach, maintaining that the astronomical rock art of the North American Southwest should be read employing "the hermeneutic traditions of western art history and art criticism" Astronomers, however, raise different questions, seeking to provide their students with identifiable precursors of their discipline, and are especially concerned with the important question of how to confirm that specific sites are, indeed, intentionally astronomical. + +The reactions of professional archaeologists to archaeoastronomy have been decidedly mixed. Some expressed incomprehension or even hostility, varying from a rejection by the archaeological mainstream of what they saw as an archaeoastronomical fringe to an incomprehension between the cultural focus of archaeologists and the quantitative focus of early archaeoastronomers. Yet archaeologists have increasingly come to incorporate many of the insights from archaeoastronomy into archaeology textbooks and, as mentioned above, some students wrote archaeology dissertations on archaeoastronomical topics. + +Since archaeoastronomers disagree so widely on the characterization of the discipline, they even dispute its name. All three major international scholarly associations relate archaeoastronomy to the study of culture, using the term Astronomy in Culture or a translation. Michael Hoskin sees an important part of the discipline as fact-collecting, rather than theorizing, and proposed to label this aspect of the discipline Archaeotopography. Ruggles and Saunders proposed Cultural Astronomy as a unifying term for the various methods of studying folk astronomies. Others have argued that astronomy is an inaccurate term, what are being studied are cosmologies and people who object to the use of logos have suggested adopting the Spanish cosmovisión. + +When debates polarise between techniques, the methods are often referred to by a colour code, based on the colours of the bindings of the two volumes from the first Oxford Conference, where the approaches were first distinguished. Green (Old World) archaeoastronomers rely heavily on statistics and are sometimes accused of missing the cultural context of what is a social practice. Brown (New World) archaeoastronomers in contrast have abundant ethnographic and historical evidence and have been described as 'cavalier' on matters of measurement and statistical analysis. Finding a way to integrate various approaches has been a subject of much discussion since the early 1990s. + +Methodology + +There is no one way to do archaeoastronomy. The divisions between archaeoastronomers tend not to be between the physical scientists and the social scientists. Instead, it tends to depend on the location and/or kind of data available to the researcher. In the Old World, there is little data but the sites themselves; in the New World, the sites were supplemented by ethnographic and historic data. The effects of the isolated development of archaeoastronomy in different places can still often be seen in research today. Research methods can be classified as falling into one of two approaches, though more recent projects often use techniques from both categories. + +Green archaeoastronomy +Green archaeoastronomy is named after the cover of the book Archaeoastronomy in the Old World. It is based primarily on statistics and is particularly apt for prehistoric sites where the social evidence is relatively scant compared to the historic period. The basic methods were developed by Alexander Thom during his extensive surveys of British megalithic sites. + +Thom wished to examine whether or not prehistoric peoples used high-accuracy astronomy. He believed that by using horizon astronomy, observers could make estimates of dates in the year to a specific day. The observation required finding a place where on a specific date the Sun set into a notch on the horizon. A common theme is a mountain that blocked the Sun, but on the right day would allow the tiniest fraction to re-emerge on the other side for a 'double sunset'. The animation below shows two sunsets at a hypothetical site, one the day before the summer solstice and one at the summer solstice, which has a double sunset. + +To test this idea he surveyed hundreds of stone rows and circles. Any individual alignment could indicate a direction by chance, but he planned to show that together the distribution of alignments was non-random, showing that there was an astronomical intent to the orientation of at least some of the alignments. His results indicated the existence of eight, sixteen, or perhaps even thirty-two approximately equal divisions of the year. The two solstices, the two equinoxes and four cross-quarter days, days halfway between a solstice and the equinox were associated with the medieval Celtic calendar. While not all these conclusions have been accepted, it has had an enduring influence on archaeoastronomy, especially in Europe. + +Euan MacKie has supported Thom's analysis, to which he added an archaeological context by comparing Neolithic Britain to the Mayan civilization to argue for a stratified society in this period. To test his ideas he conducted a couple of excavations at proposed prehistoric observatories in Scotland. Kintraw is a site notable for its four-meter high standing stone. Thom proposed that this was a foresight to a point on the distant horizon between Beinn Shianaidh and Beinn o'Chaolias on Jura. This, Thom argued, was a notch on the horizon where a double sunset would occur at midwinter. However, from ground level, this sunset would be obscured by a ridge in the landscape, and the viewer would need to be raised by two meters: another observation platform was needed. This was identified across a gorge where a platform was formed from small stones. The lack of artifacts caused concern for some archaeologists and the petrofabric analysis was inconclusive, but further research at Maes Howe and on the Bush Barrow Lozenge led MacKie to conclude that while the term 'science' may be anachronistic, Thom was broadly correct upon the subject of high-accuracy alignments. + +In contrast Clive Ruggles has argued that there are problems with the selection of data in Thom's surveys. Others have noted that the accuracy of horizon astronomy is limited by variations in refraction near the horizon. A deeper criticism of Green archaeoastronomy is that while it can answer whether there was likely to be an interest in astronomy in past times, its lack of a social element means that it struggles to answer why people would be interested, which makes it of limited use to people asking questions about the society of the past. Keith Kintigh wrote: "To put it bluntly, in many cases it doesn't matter much to the progress of anthropology whether a particular archaeoastronomical claim is right or wrong because the information doesn't inform the current interpretive questions." Nonetheless, the study of alignments remains a staple of archaeoastronomical research, especially in Europe. + +Brown archaeoastronomy +In contrast to the largely alignment-oriented statistically led methods of green archaeoastronomy, brown archaeoastronomy has been identified as being closer to the history of astronomy or to cultural history, insofar as it draws on historical and ethnographic records to enrich its understanding of early astronomies and their relations to calendars and ritual. The many records of native customs and beliefs made by Spanish chroniclers and ethnographic researchers means that brown archaeoastronomy is often associated with studies of astronomy in the Americas. + +One famous site where historical records have been used to interpret sites is Chichen Itza. Rather than analyzing the site and seeing which targets appear popular, archaeoastronomers have instead examined the ethnographic records to see what features of the sky were important to the Mayans and then sought archaeological correlates. One example which could have been overlooked without historical records is the Mayan interest in the planet Venus. This interest is attested to by the Dresden codex which contains tables with information about Venus's appearances in the sky. These cycles would have been of astrological and ritual significance as Venus was associated with Quetzalcoatl or Xolotl. Associations of architectural features with settings of Venus can be found in Chichen Itza, Uxmal, and probably some other Mesoamerican sites. + +The Temple of the Warriors bears iconography depicting feathered serpents associated with Quetzalcoatl or Kukulcan. This means that the building's alignment towards the place on the horizon where Venus first appears in the evening sky (when it coincides with the rainy season) may be meaningful. However, since both the date and the azimuth of this event change continuously, a solar interpretation of this orientation is much more likely. + +Aveni claims that another building associated with the planet Venus in the form of Kukulcan, and the rainy season at Chichen Itza is the Caracol. This is a building with a circular tower and doors facing the cardinal directions. The base faces the most northerly setting of Venus. Additionally the pillars of a stylobate on the building's upper platform were painted black and red. These are colours associated with Venus as an evening and morning star. However the windows in the tower seem to have been little more than slots, making them poor at letting light in, but providing a suitable place to view out. In their discussion of the credibility of archaeoastronomical sites, Cotte and Ruggles considered the interpretation that the Caracol is an observatory site was debated among specialists, meeting the second of their four levels of site credibility. + +Aveni states that one of the strengths of the brown methodology is that it can explore astronomies invisible to statistical analysis and offers the astronomy of the Incas as another example. The empire of the Incas was conceptually divided using ceques, radial routes emanating from the capital at Cusco. Thus there are alignments in all directions which would suggest there is little of astronomical significance, However, ethnohistorical records show that the various directions do have cosmological and astronomical significance with various points in the landscape being significant at different times of the year. In eastern Asia archaeoastronomy has developed from the history of astronomy and much archaeoastronomy is searching for material correlates of the historical record. This is due to the rich historical record of astronomical phenomena which, in China, stretches back into the Han dynasty, in the second century BC. + +A criticism of this method is that it can be statistically weak. Schaefer in particular has questioned how robust the claimed alignments in the Caracol are. Because of the wide variety of evidence, which can include artefacts as well as sites, there is no one way to practice archaeoastronomy. Despite this it is accepted that archaeoastronomy is not a discipline that sits in isolation. Because archaeoastronomy is an interdisciplinary field, whatever is being investigated should make sense both archaeologically and astronomically. Studies are more likely to be considered sound if they use theoretical tools found in archaeology like analogy and homology and if they can demonstrate an understanding of accuracy and precision found in astronomy. Both quantitative analyses and interpretations based on ethnographic analogies and other contextual evidence have recently been applied in systematic studies of architectural orientations in the Maya area and in other parts of Mesoamerica. + +Source materials +Because archaeoastronomy is about the many and various ways people interacted with the sky, there are a diverse range of sources giving information about astronomical practices. + +Alignments + +A common source of data for archaeoastronomy is the study of alignments. This is based on the assumption that the axis of alignment of an archaeological site is meaningfully oriented towards an astronomical target. Brown archaeoastronomers may justify this assumption through reading historical or ethnographic sources, while green archaeoastronomers tend to prove that alignments are unlikely to be selected by chance, usually by demonstrating common patterns of alignment at multiple sites. + +An alignment is calculated by measuring the azimuth, the angle from north, of the structure and the altitude of the horizon it faces The azimuth is usually measured using a theodolite or a compass. A compass is easier to use, though the deviation of the Earth's magnetic field from true north, known as its magnetic declination must be taken into account. Compasses are also unreliable in areas prone to magnetic interference, such as sites being supported by scaffolding. Additionally a compass can only measure the azimuth to a precision of a half a degree. + +A theodolite can be considerably more accurate if used correctly, but it is also considerably more difficult to use correctly. There is no inherent way to align a theodolite with North and so the scale has to be calibrated using astronomical observation, usually the position of the Sun. Because the position of celestial bodies changes with the time of day due to the Earth's rotation, the time of these calibration observations must be accurately known, or else there will be a systematic error in the measurements. Horizon altitudes can be measured with a theodolite or a clinometer. + +Artifacts +For artifacts such as the Sky Disc of Nebra, alleged to be a Bronze Age artefact depicting the cosmos, the analysis would be similar to typical post-excavation analysis as used in other sub-disciplines in archaeology. An artefact is examined and attempts are made to draw analogies with historical or ethnographical records of other peoples. The more parallels that can be found, the more likely an explanation is to be accepted by other archaeologists. + +A more mundane example is the presence of astrological symbols found on some shoes and sandals from the Roman Empire. The use of shoes and sandals is well known, but Carol van Driel-Murray has proposed that astrological symbols etched onto sandals gave the footwear spiritual or medicinal meanings. This is supported through citation of other known uses of astrological symbols and their connection to medical practice and with the historical records of the time. + +Another well-known artefact with an astronomical use is the Antikythera mechanism. In this case analysis of the artefact, and reference to the description of similar devices described by Cicero, would indicate a plausible use for the device. The argument is bolstered by the presence of symbols on the mechanism, allowing the disc to be read. + +Art and inscriptions + +Art and inscriptions may not be confined to artefacts, but also appear painted or inscribed on an archaeological site. Sometimes inscriptions are helpful enough to give instructions to a site's use. For example, a Greek inscription on a stele (from Itanos) has been translated as:"Patron set this up for Zeus Epopsios. Winter solstice. Should anyone wish to know: off 'the little pig' and the stele the sun turns." From Mesoamerica come Mayan and Aztec codices. These are folding books made from Amatl, processed tree bark on which are glyphs in Mayan or Aztec script. The Dresden codex contains information regarding the Venus cycle, confirming its importance to the Mayans. + +More problematic are those cases where the movement of the Sun at different times and seasons causes light and shadow interactions with petroglyphs. A widely known example is the Sun Dagger of Fajada Butte at which a glint of sunlight passes over a spiral petroglyph. The location of a dagger of light on the petroglyph varies throughout the year. At the summer solstice a dagger can be seen through the heart of the spiral; at the winter solstice two daggers appear to either side of it. It is proposed that this petroglyph was created to mark these events. Recent studies have identified many similar sites in the US Southwest and Northwestern Mexico. It has been argued that the number of solstitial markers at these sites provides statistical evidence that they were intended to mark the solstices. The Sun Dagger site on Fajada Butte in Chaco Canyon, New Mexico, stands out for its explicit light markings that record all the key events of both the solar and lunar cycles: summer solstice, winter solstice, equinox, and the major and minor lunar standstills of the Moon's 18.6 year cycle. In addition at two other sites on Fajada Butte, there are five light markings on petroglyphs recording the summer and winter solstices, equinox and solar noon. Numerous buildings and interbuilding alignments of the great houses of Chaco Canyon and outlying areas are oriented to the same solar and lunar directions that are marked at the Sun Dagger site. + +If no ethnographic nor historical data are found which can support this assertion then acceptance of the idea relies upon whether or not there are enough petroglyph sites in North America that such a correlation could occur by chance. It is helpful when petroglyphs are associated with existing peoples. This allows ethnoastronomers to question informants as to the meaning of such symbols. + +Ethnographies +As well as the materials left by peoples themselves, there are also the reports of other who have encountered them. The historical records of the Conquistadores are a rich source of information about the pre-Columbian Americans. Ethnographers also provide material about many other peoples. + +Aveni uses the importance of zenith passages as an example of the importance of ethnography. For peoples living between the tropics of Cancer and Capricorn there are two days of the year when the noon Sun passes directly overhead and casts no shadow. In parts of Mesoamerica this was considered a significant day as it would herald the arrival of rains, and so play a part in the cycle of agriculture. This knowledge is still considered important amongst Mayan Indians living in Central America today. The ethnographic records suggested to archaeoastronomers that this day may have been important to the ancient Mayans. There are also shafts known as 'zenith tubes' which illuminate subterranean rooms when the Sun passes overhead found at places like Monte Albán and Xochicalco. It is only through the ethnography that we can speculate that the timing of the illumination was considered important in Mayan society. Alignments to the sunrise and sunset on the day of the zenith passage have been claimed to exist at several sites. However, it has been shown that, since there are very few orientations that can be related to these phenomena, they likely have different explanations. + +Ethnographies also caution against over-interpretation of sites. At a site in Chaco Canyon can be found a pictograph with a star, crescent and hand. It has been argued by some astronomers that this is a record of the 1054 Supernova. However recent reexaminations of related 'supernova petroglyphs' raises questions about such sites in general. Cotte and Ruggles used the Supernova petroglyph as an example of a completely refuted site and anthropological evidence suggests other interpretations. The Zuni people, who claim a strong ancestral affiliation with Chaco, marked their sun-watching station with a crescent, star, hand and sundisc, similar to those found at the Chaco site. + +Ethnoastronomy is also an important field outside of the Americas. For example, anthropological work with Aboriginal Australians is producing much information about their Indigenous astronomies and about their interaction with the modern world. + +Recreating the ancient sky + +Once the researcher has data to test, it is often necessary to attempt to recreate ancient sky conditions to place the data in its historical environment. + +Declination + +To calculate what astronomical features a structure faced a coordinate system is needed. The stars provide such a system. On a clear night observe the stars spinning around the celestial pole can be observed. This point is +90° of the North Celestial Pole or −90° observing the Southern Celestial Pole. The concentric circles the stars trace out are lines of celestial latitude, known as declination. The arc connecting the points on the horizon due East and due West (if the horizon is flat) and all points midway between the Celestial Poles is the Celestial Equator which has a declination of 0°. The visible declinations vary depending where you are on the globe. Only an observer on the North Pole of Earth would be unable to see any stars from the Southern Celestial Hemisphere at night (see diagram below). Once a declination has been found for the point on the horizon that a building faces it is then possible to say whether a specific body can be seen in that direction. + +Solar positioning +While the stars are fixed to their declinations the Sun is not. The rising point of the Sun varies throughout the year. It swings between two limits marked by the solstices a bit like a pendulum, slowing as it reaches the extremes, but passing rapidly through the midpoint. If an archaeoastronomer can calculate from the azimuth and horizon height that a site was built to view a declination of +23.5° then he or she need not wait until 21 June to confirm the site does indeed face the summer solstice. For more information see History of solar observation. + +Lunar positioning +The Moon's appearance is considerably more complex. Its motion, like the Sun, is between two limits—known as lunistices rather than solstices. However, its travel between lunistices is considerably faster. It takes a sidereal month to complete its cycle rather than the year-long trek of the Sun. This is further complicated as the lunistices marking the limits of the Moon's movement move on an 18.6 year cycle. For slightly over nine years the extreme limits of the Moon are outside the range of sunrise. For the remaining half of the cycle the Moon never exceeds the limits of the range of sunrise. However, much lunar observation was concerned with the phase of the Moon. The cycle from one New Moon to the next runs on an entirely different cycle, the Synodic month. Thus when examining sites for lunar significance the data can appear sparse due to the extremely variable nature of the Moon. See Moon for more details. + +Stellar positioning + +Finally there is often a need to correct for the apparent movement of the stars. On the timescale of human civilisation the stars have largely maintained the same position relative to each other. Each night they appear to rotate around the celestial poles due to the Earth's rotation about its axis. However, the Earth spins rather like a spinning top. Not only does the Earth rotate, it wobbles. The Earth's axis takes around 25,800 years to complete one full wobble. The effect to the archaeoastronomer is that stars did not rise over the horizon in the past in the same places as they do today. Nor did the stars rotate around Polaris as they do now. In the case of the Egyptian pyramids, it has been shown they were aligned towards Thuban, a faint star in the constellation of Draco. The effect can be substantial over relatively short lengths of time, historically speaking. For instance a person born on 25 December in Roman times would have been born with the Sun in the constellation Capricorn. In the modern period a person born on the same date would have the Sun in Sagittarius due to the precession of the equinoxes. + +Transient phenomena + +Additionally there are often transient phenomena, events which do not happen on an annual cycle. Most predictable are events like eclipses. In the case of solar eclipses these can be used to date events in the past. A solar eclipse mentioned by Herodotus enables us to date a battle between the Medes and the Lydians, which following the eclipse failed to happen, to 28 May, 585 BC. Other easily calculated events are supernovae whose remains are visible to astronomers and therefore their positions and magnitude can be accurately calculated. + +Some comets are predictable, most famously Halley's Comet. Yet as a class of object they remain unpredictable and can appear at any time. Some have extremely lengthy orbital periods which means their past appearances and returns cannot be predicted. Others may have only ever passed through the Solar System once and so are inherently unpredictable. + +Meteor showers should be predictable, but some meteors are cometary debris and so require calculations of orbits which are currently impossible to complete. Other events noted by ancients include aurorae, sun dogs and rainbows all of which are as impossible to predict as the ancient weather, but nevertheless may have been considered important phenomena. + +Major topics of archaeoastronomical research + +The use of calendars +A common justification for the need for astronomy is the need to develop an accurate calendar for agricultural reasons. Ancient texts like Hesiod's Works and Days, an ancient farming manual, would appear to partially confirm this: astronomical observations are used in combination with ecological signs, such as bird migrations to determine the seasons. Ethnoastronomical studies of the Hopi of the southwestern United States indicate that they carefully observed the rising and setting positions of the Sun to determine the proper times to plant crops. However, ethnoastronomical work with the Mursi of Ethiopia shows that their luni-solar calendar was somewhat haphazard, indicating the limits of astronomical calendars in some societies. All the same, calendars appear to be an almost universal phenomenon in societies as they provide tools for the regulation of communal activities. + +One such example is the Tzolk'in calendar of 260 days. Together with the 365-day year, it was used in pre-Columbian Mesoamerica, forming part of a comprehensive calendrical system, which combined a series of astronomical observations and ritual cycles. Archaeoastronomical studies throughout Mesoamerica have shown that the orientations of most structures refer to the Sun and were used in combination with the 260-day cycle for scheduling agricultural activities and the accompanying rituals. The distribution of dates and intervals marked by orientations of monumental ceremonial complexes in the area along the southern Gulf Coast in Mexico, dated to about 1100 to 700 BCE, represents the earliest evidence of the use of this cycle. + +Other peculiar calendars include ancient Greek calendars. These were nominally lunar, starting with the New Moon. In reality the calendar could pause or skip days with confused citizens inscribing dates by both the civic calendar and ton theoi, by the moon. The lack of any universal calendar for ancient Greece suggests that coordination of panhellenic events such as games or rituals could be difficult and that astronomical symbolism may have been used as a politically neutral form of timekeeping. Orientation measurements in Greek temples and Byzantine churches have been associated to deity's name day, festivities, and special events. + +Myth and cosmology + +Another motive for studying the sky is to understand and explain the universe. In these cultures myth was a tool for achieving this, and the explanations, while not reflecting the standards of modern science, are cosmologies. + +The Incas arranged their empire to demonstrate their cosmology. The capital, Cusco, was at the centre of the empire and connected to it by means of ceques, conceptually straight lines radiating out from the centre. These ceques connected the centre of the empire to the four suyus, which were regions defined by their direction from Cusco. The notion of a quartered cosmos is common across the Andes. Gary Urton, who has conducted fieldwork in the Andean villagers of Misminay, has connected this quartering with the appearance of the Milky Way in the night sky. In one season it will bisect the sky and in another bisect it in a perpendicular fashion. + +The importance of observing cosmological factors is also seen on the other side of the world. The Forbidden City in Beijing is laid out to follow cosmic order though rather than observing four directions. The Chinese system was composed of five directions: North, South, East, West and Centre. The Forbidden City occupied the centre of ancient Beijing. One approaches the Emperor from the south, thus placing him in front of the circumpolar stars. This creates the situation of the heavens revolving around the person of the Emperor. The Chinese cosmology is now better known through its export as feng shui. + +There is also much information about how the universe was thought to work stored in the mythology of the constellations. The Barasana of the Amazon plan part of their annual cycle based on observation of the stars. When their constellation of the Caterpillar-Jaguar (roughly equivalent to the modern Scorpius) falls they prepare to catch the pupating caterpillars of the forest as they fall from the trees. The caterpillars provide food at a season when other foods are scarce. + +A more well-known source of constellation myth are the texts of the Greeks and Romans. The origin of their constellations remains a matter of vigorous and occasionally fractious debate. + +The loss of one of the sisters, Merope, in some Greek myths may reflect an astronomical event wherein one of the stars in the Pleiades disappeared from view by the naked eye. + +Giorgio de Santillana, professor of the History of Science in the School of Humanities at the Massachusetts Institute of Technology, along with Hertha von Dechend believed that the old mythological stories handed down from antiquity were not random fictitious tales but were accurate depictions of celestial cosmology clothed in tales to aid their oral transmission. The chaos, monsters and violence in ancient myths are representative of the forces that shape each age. They believed that ancient myths are the remains of preliterate astronomy that became lost with the rise of the Greco-Roman civilization. Santillana and von Dechend in their book Hamlet's Mill, An Essay on Myth and the Frame of Time (1969) clearly state that ancient myths have no historical or factual basis other than a cosmological one encoding astronomical phenomena, especially the precession of the equinoxes. Santillana and von Dechend's approach is not widely accepted. + +Displays of power + +By including celestial motifs in clothing it becomes possible for the wearer to make claims the power on Earth is drawn from above. It has been said that the Shield of Achilles described by Homer is also a catalogue of constellations. In North America shields depicted in Comanche petroglyphs appear to include Venus symbolism. + +Solsticial alignments also can be seen as displays of power. When viewed from a ceremonial plaza on the Island of the Sun (the mythical origin place of the Sun) in Lake Titicaca, the Sun was seen to rise at the June solstice between two towers on a nearby ridge. The sacred part of the island was separated from the remainder of it by a stone wall and ethnographic records indicate that access to the sacred space was restricted to members of the Inca ruling elite. Ordinary pilgrims stood on a platform outside the ceremonial area to see the solstice Sun rise between the towers. + +In Egypt the temple of Amun-Re at Karnak has been the subject of much study. Evaluation of the site, taking into account the change over time of the obliquity of the ecliptic show that the Great Temple was aligned on the rising of the midwinter Sun. The length of the corridor down which sunlight would travel would have limited illumination at other times of the year. + +In a later period the Serapeum of Alexandria was also said to have contained a solar alignment so that, on a specific sunrise, a shaft of light would pass across the lips of the statue of Serapis thus symbolising the Sun saluting the god. + +Major sites of archaeoastronomical interest + +Clive Ruggles and Michel Cotte recently edited a book on heritage sites of astronomy and archaeoastronomy which discussed a worldwide sample of astronomical and archaeoastronomical sites and provided criteria for the classification of archaeoastronomical sites. + +Newgrange + +Newgrange is a passage tomb in the Republic of Ireland dating from around 3,300 to 2,900 BC For a few days around the Winter Solstice light shines along the central passageway into the heart of the tomb. What makes this notable is not that light shines in the passageway, but that it does not do so through the main entrance. Instead it enters via a hollow box above the main doorway discovered by Michael O'Kelly. It is this roofbox which strongly indicates that the tomb was built with an astronomical aspect in mind. In their discussion of the credibility of archaeoastronomical sites, Cotte and Ruggles gave Newgrange as an example of a Generally accepted site, the highest of their four levels of credibility. Clive Ruggles notes: + +Egypt + +Since the first modern measurements of the precise cardinal orientations of the pyramids by Flinders Petrie, various astronomical methods have been proposed for the original establishment of these orientations. It was recently proposed that this was done by observing the positions of two stars in the Plough / Big Dipper which was known to Egyptians as the thigh. It is thought that a vertical alignment between these two stars checked with a plumb bob was used to ascertain where north lay. The deviations from true north using this model reflect the accepted dates of construction. + +Some have argued that the pyramids were laid out as a map of the three stars in the belt of Orion, although this theory has been criticized by reputable astronomers. The site was instead probably governed by a spectacular hierophany which occurs at the summer solstice, when the Sun, viewed from the Sphinx terrace, forms—together with the two giant pyramids—the symbol Akhet, which was also the name of the Great Pyramid. Further, the south east corners of all the three pyramids align towards the temple of Heliopolis, as first discovered by the Egyptologist Mark Lehner. + +The astronomical ceiling of the tomb of Senenmut (BC) contains the Celestial Diagram depicting circumpolar constellations in the form of discs. Each disc is divided into 24 sections suggesting a 24-hour time period. Constellations are portrayed as sacred deities of Egypt. The observation of lunar cycles is also evident. + +El Castillo + +El Castillo, also known as Kukulcán's Pyramid, is a Mesoamerican step-pyramid built in the centre of Mayan center of Chichen Itza in Mexico. Several architectural features have suggested astronomical elements. Each of the stairways built into the sides of the pyramid has 91 steps. Along with the extra one for the platform at the top, this totals 365 steps, which is possibly one for each day of the year (365.25) or the number of lunar orbits in 10,000 rotations (365.01). + +A visually striking effect is seen every March and September as an unusual shadow occurs around the equinoxes. Light and shadow phenomena have been proposed to explain a possible architectural hierophany involving the sun at Chichén Itzá in a Maya Toltec structure dating to about 1000 CE. A shadow appears to descend the west balustrade of the northern stairway. The visual effect is of a serpent descending the stairway, with its head at the base in light. Additionally the western face points to sunset around 25 May, traditionally the date of transition from the dry to the rainy season. The intended alignment was, however, likely incorporated in the northern (main) facade of the temple, as it corresponds to sunsets on May 20 and July 24, recorded also by the central axis of Castillo at Tulum. The two dates are separated by 65 and 300 days, and it has been shown that the solar orientations in Mesoamerica regularly correspond to dates separated by calendrically significant intervals (multiples of 13 and 20 days). In their discussion of the credibility of archaeoastronomical sites, Cotte and Ruggles used the "equinox hierophany" at Chichén Itzá as an example of an Unproven site, the third of their four levels of credibility. + +Stonehenge + +Many astronomical alignments have been claimed for Stonehenge, a complex of megaliths and earthworks in the Salisbury Plain of England. The most famous of these is the midsummer alignment, where the Sun rises over the Heel Stone. However, this interpretation has been challenged by some archaeologists who argue that the midwinter alignment, where the viewer is outside Stonehenge and sees the Sun setting in the henge, is the more significant alignment, and the midsummer alignment may be a coincidence due to local topography. In their discussion of the credibility of archaeoastronomical sites, Cotte and Ruggles gave Stonehenge as an example of a Generally accepted site, the highest of their four levels of credibility. + +As well as solar alignments, there are proposed lunar alignments. The four station stones mark out a rectangle. The short sides point towards the midsummer sunrise and midwinter sunset. The long sides if viewed towards the south-east, face the most southerly rising of the Moon. Aveni notes that these lunar alignments have never gained the acceptance that the solar alignments have received. The Heel Stone azimuth is one-seventh of circumference, matching the latitude of Avebury, while summer solstice sunrise azimuth is no longer equal to the construction era direction. + +Maeshowe + +This is an architecturally outstanding Neolithic chambered tomb on the mainland of Orkney, Scotland—probably dating to the early 3rd millennium BC, and where the setting Sun at midwinter shines down the entrance passage into the central chamber (see Newgrange). In the 1990s further investigations were carried out to discover whether this was an accurate or an approximate solar alignment. Several new aspects of the site were discovered. In the first place the entrance passage faces the hills of the island Hoy, about 10 miles away. Secondly, it consists of two straight lengths, angled at a few degrees to each other. Thirdly, the outer part is aligned towards the midwinter sunset position on a level horizon just to the left of Ward Hill on Hoy. Fourthly the inner part points directly at the Barnhouse standing stone about 400m away and then to the right end of the summit of Ward Hill, just before it dips down to the notch between it at Cuilags to the right. This indicated line points to sunset on the first Sixteenths of the solar year (according to A. Thom) before and after the winter solstice and the notch at the base of the right slope of the Hill is at the same declination. Fourthly a similar 'double sunset' phenomenon is seen at the right end of Cuilags, also on Hoy; here the date is the first Eighth of the year before and after the winter solstice, at the beginning of November and February respectively—the Old Celtic festivals of Samhain and Imbolc. This alignment is not indicated by an artificial structure but gains plausibility from the other two indicated lines. Maeshowe is thus an extremely sophisticated calendar site which must have been positioned carefully in order to use the horizon foresights in the ways described. + +Uxmal + +Uxmal is a Mayan city in the Puuc Hills of Yucatán Peninsula, Mexico. The Governor's Palace at Uxmal is often used as an exemplar of why it is important to combine ethnographic and alignment data. The palace is aligned with an azimuth of 118° on the pyramid of Cehtzuc. This alignment corresponds approximately to the southernmost rising and, with a much greater precision, to the northernmost setting of Venus; both phenomena occur once every eight years. By itself this would not be sufficient to argue for a meaningful connection between the two events. The palace has to be aligned in one direction or another and why should the rising of Venus be any more important than the rising of the Sun, Moon, other planets, Sirius et cetera? The answer given is that not only does the palace point towards significant points of Venus, it is also covered in glyphs which stand for Venus and Mayan zodiacal constellations. Moreover, the great northerly extremes of Venus always occur in late April or early May, coinciding with the onset of the rainy season. The Venus glyphs placed in the cheeks of the Maya rain god Chac, most likely referring to the concomitance of these phenomena, support the west-working orientation scheme. + +Chaco Canyon + +In Chaco Canyon, the center of the ancient Pueblo culture in the American Southwest, numerous solar and lunar light markings and architectural and road alignments have been documented. These findings date to the 1977 discovery of the Sun Dagger site by Anna Sofaer. Three large stone slabs leaning against a cliff channel light and shadow markings onto two spiral petroglyphs on the cliff wall, marking the solstices, equinoxes and the lunar standstills of the 18.6 year cycle of the moon. Subsequent research by the Solstice Project and others demonstrated that numerous building and interbuilding alignments of the great houses of Chaco Canyon are oriented to solar, lunar and cardinal directions. In addition, research shows that the Great North Road, a thirty-five mile engineered "road", was constructed not for utilitarian purposes but rather to connect the ceremonial center of Chaco Canyon with the direction north. + +Lascaux Cave + +In recent years, new research has suggested that the Lascaux cave paintings in France may incorporate prehistoric star charts. Michael Rappenglueck of the University of Munich argues that some of the non-figurative dot clusters and dots within some of the figurative images correlate with the constellations of Taurus, the Pleiades and the grouping known as the "Summer Triangle". Based on her own study of the astronomical significance of Bronze Age petroglyphs in the Vallée des Merveilles and her extensive survey of other prehistoric cave painting sites in the region—most of which appear to have been selected because the interiors are illuminated by the setting Sun on the day of the winter solstice—French researcher Chantal Jègues-Wolkiewiez has further proposed that the gallery of figurative images in the Great Hall represents an extensive star map and that key points on major figures in the group correspond to stars in the main constellations as they appeared in the Paleolithic. Appliying phylogenetics to myths of the Cosmic Hunt, Julien d'Huy suggested that the palaeolithic version of this story could be the following: there is an animal that is a horned herbivore, especially an elk. One human pursues this ungulate. The hunt locates or gets to the sky. The animal is alive when it is transformed into a constellation. It forms the Big Dipper. This story may be represented in the famous Lascaux shaft 'scene' + +Fringe archaeoastronomy + +Archaeoastronomy owes something of this poor reputation among scholars to its occasional misuse to advance a range of pseudo-historical accounts. During the 1930s, Otto S. Reuter compiled a study entitled Germanische Himmelskunde, or "Teutonic Skylore". The astronomical orientations of ancient monuments claimed by Reuter and his followers would place the ancient Germanic peoples ahead of the Ancient Near East in the field of astronomy, demonstrating the intellectual superiority of the "Aryans" (Indo-Europeans) over the Semites. + +More recently Gallagher, Pyle, and Fell interpreted inscriptions in West Virginia as a description in Celtic Ogham alphabet of the supposed winter solstitial marker at the site. The controversial translation was supposedly validated by a problematic archaeoastronomical indication in which the winter solstice Sun shone on an inscription of the Sun at the site. Subsequent analyses criticized its cultural inappropriateness, as well as its linguistic and archaeoastronomical claims, to describe it as an example of "cult archaeology". + +Archaeoastronomy is sometimes related to the fringe discipline of Archaeocryptography, when its followers attempt to find underlying mathematical orders beneath the proportions, size, and placement of archaeoastronomical sites such as Stonehenge and the Pyramid of Kukulcán at Chichen Itza. + +India + +Since the 19th century, numerous scholars have sought to use archaeoastronomical calculations to demonstrate the antiquity of Ancient Indian Vedic culture, computing the dates of astronomical observations ambiguously described in ancient poetry to as early as 4000 BC. David Pingree, a historian of Indian astronomy, condemned "the scholars who perpetrate wild theories of prehistoric science and call themselves archaeoastronomers." + +Organisations and publications +There are currently three academic organisations for scholars of archaeoastronomy. ISAACthe International Society for Archaeoastronomy and Astronomy in Culturewas founded in 1995 and now sponsors the Oxford conferences and Archaeoastronomy – the Journal of Astronomy in Culture. SEAC – La Société Européenne pour l'Astronomie dans la Culture +is slightly older; it was created in 1992. SEAC holds annual conferences in Europe and publishes refereed conference proceedings on an annual basis. There is also SIACLa Sociedad Interamericana de Astronomía en la Cultura, primarily a Latin American organisation which was founded in 2003. In 2009, the Society for Cultural Astronomy in the American Southwest (SCAAS) was founded, a regional organisation focusing on the astronomies of the native peoples of the Southwestern United States; it has since held seven meetings and workshops. Two new organisations focused on regional archaeoastronomy were founded in 2013: ASIA – the Australian Society for Indigenous Astronomy in Australia and SMART – the Society of Māori Astronomy Research and Traditions in New Zealand. Additionally, in 2017, the Romanian Society for Cultural Astronomy ex was founded. It holds an annual international conference and has published the first monograph on archaeo- and ethnoastronomy in Romania (2019). + +Additionally the Journal for the History of Astronomy publishes many archaeoastronomical papers. For twenty-seven volumes (from 1979 to 2002) it published an annual supplement Archaeoastronomy. The Journal of Astronomical History and Heritage (National Astronomical Research Institute of Thailand), Culture & Cosmos (University of Wales, UK) and Mediterranean Archaeology and Archaeometry (University of Aegean, Greece) also publish papers on archaeoastronomy. + +Various national archaeoastronomical projects have been undertaken. Among them is the program at the Tata Institute of Fundamental Research named "Archaeo Astronomy in Indian Context" that has made interesting findings in this field. + +See also + +References + +Citations + +Bibliography + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +   + + + + + + + + + + + + + + + + + + + + + + + . reprinted in Michael H. Shank, ed., The Scientific Enterprise in Antiquity and the Middle Ages (Chicago: Univ. of Chicago Pr., 2000), pp. 30–39. + + + + + + + + + + Three volumes; 217 articles. + + + + + + + + + + + + + + + + + Šprajc, Ivan (2015). Governor's Palace at Uxmal. In: Handbook of Archaeoastronomy and Ethnoastronomy, ed. by Clive L. N. Ruggles, New York: Springer, pp. 773–81 + + Šprajc, Ivan, and Pedro Francisco Sánchez Nava (2013). Astronomía en la arquitectura de Chichén Itzá: una reevaluación. Estudios de Cultura Maya XLI: 31–60. + +Further reading + +External links + + Astronomy before History - A chapter from The Cambridge Concise History of Astronomy, Michael Hoskin ed., 1999. + Clive Ruggles: images, bibliography, software, and synopsis of his course at the University of Leicester. + Traditions of the Sun – NASA and others exploring the world's ancient observatories. + Ancient Observatories: Timeless Knowledge NASA Poster on ancient (and modern) observatories. + Astronomy is the most ancient of the sciences. (About Kazakh folk astronomy) + + +Ancient astronomy +Astronomical sub-disciplines +Archaeological sub-disciplines +Traditional knowledge +Articles containing video clips +Andrzej Sapkowski (; born 21 June 1948) is a Polish fantasy writer, essayist, translator and a trained economist. He is best known for his six-volume series of books The Witcher, which revolves around the eponymous "witcher," a monster-hunter, Geralt of Rivia. It began with the publication of Sword of Destiny (1992), and was completed with the publication of standalone prequel novel Season of Storms (2013). The saga has been popularized through television, stage, comic books, video games and translated into 37 languages making him the second most-translated Polish science fiction and fantasy writer after Stanisław Lem. + +He was born in Łódź and initially pursued a career as an economist after graduating from the University of Łódź. He turned to writing, first as a translator and later as an author of fantasy books, following the success of his first short story The Witcher published in 1986 in the Fantastyka magazine. + +Described as the "Polish Tolkien", he wrote ten novels and eight short story collections, which sold over 30 million copies worldwide. The influence of Slavic mythology is seen as a characteristic feature of many of his works. He is a five-time recipient of the Zajdel Award, Poland's most popular science fiction and fantasy prize, as well as many other awards and honors including David Gemmell Award, World Fantasy Life Achievement Award and the Medal for Merit to Culture – Gloria Artis. + +Early life +He was born on 21 June 1948 in Łódź, in central Poland. His father served in the Polish People's Army and participated in the Battle of Berlin. After the end of World War II, his parents lived near Nowa Sól before settling in Łódź. He attended the Bolesław Prus High School No. 21. He also studied economics at the University of Łódź, and before turning to writing, he had worked as a senior sales representative for a foreign trade company. He started his literary career as a translator, in particular, of science fiction. Among the first works translated by him was The Words of Guru by Cyril M. Kornbluth. + +Career + +Major works +He says he wrote his first short story, The Witcher (1986), ("Wiedźmin", also translated "The Hexer" or "Spellmaker"), on a whim, in order to enter a contest by Polish science fiction and fantasy magazine Fantastyka. In an interview, he said that being a businessman at the time and thus familiar with marketing, he knew how to sell, and indeed, he won third prize. The story was published in Fantastyka in 1986 and was enormously successful both with readers and critics. Sapkowski has created a cycle of tales based on the world of "The Witcher", comprising three collections of short stories and eight novels. This cycle and his other works have made him one of the best-known fantasy authors in Poland in the 1990s. + +The main character of "The Witcher" is Geralt of Rivia, trained as a monster hunter since childhood. Geralt exists in a morally ambiguous universe, yet manages to maintain his own coherent code of ethics. At the same time cynical and noble, Geralt has been compared to Raymond Chandler's signature character Philip Marlowe. The world in which these adventures take place is heavily influenced by Slavic mythology. + +In her review of Blood of Elves, Alice Wybrew of Total Sci-Fi writes that "Moving effortlessly between moments of wrought emotion and staggeringly effective action, to lengthy periods of political discussion and war stratagems, Sapkowski addresses every aspect of a good fantasy novel eloquently and with ease. His style reads as easily as David Gemmel, but hits harder and deeper than his late fantasy comrade. Creating a world that is both familiar and comfortable, it is through his inventive use of character manipulation that he generates a new and realistic experience". Alex Jay of Polygon further observes that within Sapkowski's fantasy tales, "there are parallels to the complicated history of ethnic strife and resistance to oppression in Central and Eastern Europe". The depictions of the disputes between nonhumans and humans "echo real-world disputes over territory and citizenship that draw dividing lines according to race, nationality, or ethnicity". + +In 2001, he published the Manuscript Discovered in a Dragon's Cave, an original and personal guide to fantasy literature. It was written in the form of an encyclopaedia and the author discusses in it the history of the literary genre, well-known fantasy heroes, descriptions of magic terminology as well as major works of notable writers including J.R.R. Tolkien's The Hobbit and The Lord of the Rings, Robert E. Howard's Conan, C.S. Lewis's The Chronicles of Narnia, Ursula K. Le Guin's Earthsea, Roger Zelazny's The Chronicles of Amber, J.K. Rowling's Harry Potter or George R.R. Martin's A Song of Ice and Fire. + +Sapkowski's next book series was The Hussite Trilogy set in the 15th century at the time of the Hussite Wars with Reinmar of Bielawa as the main protagonist. Mariusz Czubaj writes: + +Although The Hussite Trilogy proved less popular compared to The Witcher, it has been described as the author's "magnum opus". Published between 2002 and 2006, the series was released as an audiobook in 2019. + +In August 2023, Sapkowski announced he was working on a new novel from The Witcher universe during an on-line meeting with his Ukrainian fans. He added that his work on the book "may take a year, but no longer" giving it a potential expected publication date at some point in 2024. + +Legal dispute with CD Projekt +In October 2018, he filed a lawsuit against CD Projekt demanding 60 million zloty ($16.1 million) in royalty payments from the company for using the Witcher universe in their computer games. The lawsuit was launched despite the fact that Sapkowski had sold the video game rights to the Witcher for a single sum, rather than through a royalties contract. Sapkowski and his lawyers based their lawsuit on Article 44 of the Copyright and Related Rights Act. + +CD Projekt released a statement claiming that the author's demands are groundless and that the company had legitimately and legally acquired copyright to Sapkowski's works. His decision was criticized by many commentators and gaming journalists including Dmitry Glukhovsky, the author of Metro 2033, who described him as "an old fool" and noted that without the gaming franchise, the Witcher series "would never get this crazy international readership" and would have remained popular only in Central and Eastern Europe. + +On 20 December 2019, the writer and the company resolved the lawsuit with an amicable settlement. The company stated this deal was made in an effort "to maintain good relations with authors of works which have inspired CD Projekt Red's own creations." The details of this arrangement were not made public. + +Personal life + +Sapkowski resides in his hometown of Łódź in central Poland. He had a son named Krzysztof (1972–2019), who was an avid reader of the Polish Fantastyka magazine, and for whom he wrote the first Witcher story, who has since deceased. + +Sapkowski is a member of the Polish Writers' Association. In an interview, he mentioned that his favorite writers included Ernest Hemingway, Mikhail Bulgakov, Raymond Chandler and Umberto Eco. + +In 2005, Stanisław Bereś conducted a lengthy interview with Sapkowski that was eventually published in a book form as Historia i fantastyka. + +Translations and adaptations of Sapkowski's works +Sapkowski's books have been translated into Bulgarian, Chinese, Croatian, Czech, Dutch, English, Estonian, Finnish, French, Georgian, German, Hungarian, Italian, Korean, Lithuanian, Norwegian, Persian, Portuguese, Romanian, Russian, Serbian, Slovak, Spanish, Swedish, Turkish, and Ukrainian. An English translation of The Last Wish short story collection was published by Gollancz in 2007. From 2008, the Witcher saga is published by Gollancz. The English translation of Sapkowski's novel Blood of Elves won the David Gemmell Legend Award in 2009. + +In the years 1993–1995, a six-issue comic book series entitled The Witcher was released in the Komiks magazine by Prószyński i S-ka publishing house. The comic was written by Maciej Parowski and illustrated by Bogusław Polch. The comics were the first attempt to portray the Witcher universe outside the novels. Since 2014, a comic book series The Witcher has been published by the American publisher Dark Horse Comics. The stories presented in the series are mostly originals, written not by Andrzej Sapkowski but by other writers; the exception being volume 2, Fox Children, which adapted a story from the anthology Season of Storms. + +In 2001, a television series based on the Witcher cycle was released in Poland and internationally, entitled Wiedźmin (The Hexer). A film by the same title was compiled from excerpts of the television series but both have been critical and box office failures. + +In 2009, Russian heavy metal band Esse staged The Road with No Return, a rock opera based on the works by Sapkowski. Yevgeny Pronin is the author of the libretto and the composer of much of the opera's music. The premiere of the opera took place the same year in Rostov-on-Don and was subsequently released as a DVD in 2012. + +The Polish game developer, CD Projekt Red, created a role-playing game series based on The Witcher universe. The first game, titled simply The Witcher, was first released in October 2007. The sequel, The Witcher 2: Assassins of Kings was released in 2011. The third game in the trilogy, The Witcher 3: Wild Hunt, was released in May 2015. The game shipped over 40 million copies, making it one of the best selling video games of all time. + +In May 2017, Netflix commissioned The Witcher, an English-language adaptation of the book series. The Witcher television series premiered on Netflix on 20 December 2019. Sapkowski served for a while as a creative consultant on the project. The popularity of the Netflix show led to Sapkowski topping Amazon's list of best-selling authors ahead of J.K. Rowling and Stephen King. A spin-off anime The Witcher: Nightmare of the Wolf, produced by Lauren Schmidt Hissrich, premiered in 2021. + +In September 2017, a musical Wiedźmin (The Witcher) directed by Wojciech Kościelniak was premiered at the Musical Theatre in Gdynia. + +The Witcher: Blood Origin is a fantasy miniseries created by Declan de Barra and Lauren Schmidt Hissrich adapted from The Witcher book series which serves as a prequel to the Netflix television series. It was released on Netflix in December 2022. + +Awards and recognition +Sapkowski is a recipient of numerous awards and honours both Polish and foreign including: + +2016: World Fantasy Award—Life Achievement for The Witcher saga +2012: Tähtifantasia Award (Finland) for his short story Sword of Destiny translated from Polish by Tapani Kärkkäinen; Science Fiction & Fantasy Translation Award nomination for his novel Spellmaker, translated from the Polish by Michael Kandel +2011: FantLab's Book of the Year Award (Russia) for his short story Żmija (Viper) in the Best Translated Novella or Short Story category +2010: European Science Fiction Society "European Grand Master" honorary award +2009: David Gemmell Legend Award +2008: Honorary citizenship of the city of Łódź +2003: Ignotus Award (Spain) for The Last Wish in the Best Anthology category and for Muzykanci (The Musicians) in the Best Foreign Short Story category; Nike Award nomination (Poland's top literary prize) for his novel Narrenturm +2002: Janusz A. Zajdel for his novel Narrenturm +1997: Polityka's Passport award, which is awarded annually to artists who have strong prospects for international success +1996: European Science Fiction Society Hall of Fame: author +1995: Raczyński Library Award for lifetime achievements +1994: Janusz A. Zajdel Award for his novel Krew elfów (Blood of Elves) +1993: Ikaros Award (Czech Republic); Janusz A. Zajdel Award for his short story W leju po bombie (In a Bomb Crater) +1992: Janusz A. Zajdel Award for his short story Miecz przeznaczenia (Sword of Destiny) +1990: Janusz A. Zajdel Award for his short story Mniejsze zło (The Lesser of Two Evils) + +Orders +2014: Silver Medal Gloria Artis, conferred by the Ministry of Culture and National Heritage of the Republic of Poland + +Bibliography + +The Witcher Saga + +Short story collections +The Witcher (pl:Wiedźmin, 1986), 5 stories. Currently out of print, although 4 of its stories were reprinted in The Last Wish along with new material, while the fifth story was reprinted in Something ends, Something begins and The Malady and Other Stories. +Sword of Destiny (Miecz przeznaczenia, 1992), 6 stories. English edition: 2015 +The Last Wish (Ostatnie życzenie, 1993), 7 stories. English edition: 2007 (in US: 2008). Its stories (including both its original stories and the stories which it republishes from The Witcher) take place before Sword of Destiny even though it was published later. +The short story "The Hexer" in the English anthology Chosen by Fate: Zajdel Award Winner Anthology (by SuperNOVA in cooperation with the Silesian Club of Fantasy Literature, 2000) is an English translation by Agnieszka Fulińska of the short story "The Witcher" which had previously been published in Polish in The Witcher and The Last Wish. The Last Wish was later translated into English in full. +The short story "Spellmaker" in the English anthology A Polish Book of Monsters (edited and translated by Michael Kandel, 2010) is another translation of the short story "The Witcher" which had previously been published in The Witcher, The Last Wish, and Chosen by Fate: Zajdel Award Winner Anthology. +Something Ends, Something Begins (pl:Coś się kończy, coś się zaczyna, 2000), 8 stories. Only two of its stories are related to The Witcher saga ("The Road with No Return" and the titular "Something Ends, Something Begins"). +The Malady and Other Stories (:pl:Maladie i inne opowiadania, 2012), 10 stories. It includes the 8 stories from Something ends, Something begins plus two new stories that aren't related to The Witcher saga. The only one of its stories that was translated into English is the titular "The Malady" which was published in 2014 under the title The Malady and Other Stories, although that English publication didn't include the other 9 stories from the Polish collection of the same name. + +Pentalogy +Blood of Elves (Krew elfów, 1994). English edition: 2009 +Time of Contempt (Czas pogardy, 1995). English edition: 27 June 2013 +Baptism of Fire (Chrzest ognia, 1996). English edition: 6 March 2014 +The Tower of Swallows (Wieża Jaskółki, 1997). English edition: May 2016 +Lady of the Lake (Pani Jeziora, 1999). English edition: 14 March 2017 + +Standalone Prequel novel + Season of Storms (Sezon burz, 2013). English edition: 22 May 2018 – set between the short stories in The Last Wish + +Hussite Trilogy +The Tower of Fools (Narrenturm, 2002). English edition: 2020 +Warriors of God (Boży bojownicy, 2004) +Light Perpetual (Lux perpetua, 2006) + +Other novels +Viper (Żmija, 2009), a stand-alone novel set during the Soviet–Afghan War + +Other works +The Eye of Yrrhedes (Oko Yrrhedesa, 1995), roleplaying game +The World of King Arthur. Maladie (Świat króla Artura. Maladie, 1995), essay and an illustrated short story set in Arthurian mythology +Manuscript Discovered in a Dragon's Cave (Rękopis znaleziony w Smoczej Jaskini, 2001), fantasy encyclopedic compendium + +See also +Polish literature +Science fiction and fantasy in Poland +List of Polish writers +Stanisław Lem +Jacek Dukaj +Janusz A. Zajdel Award +Toss a Coin to Your Witcher +Gwent: The Witcher Card Game +The Witcher: Monster Slayer + +References + +External links + +Andrzej Sapkowski's official site + + Andrzej Sapkowski at Culture.pl +Canon of fantasy literature, by Andrzej Sapkowski + + +1948 births +Living people +People from Łódź +Polish fantasy writers +20th-century Polish novelists +21st-century Polish novelists +Polish male novelists +Polish male short story writers +20th-century Polish male writers +21st-century Polish male writers +20th-century short story writers +21st-century short story writers +Writers of historical fiction set in the Middle Ages +Polish translators +Polish economists +Constructed language creators +University of Łódź alumni +Recipients of the Silver Medal for Merit to Culture – Gloria Artis +World Fantasy Award-winning writers +Slavic mythology in popular culture +Works based on Slavic mythology +Writers from Łódź +People from Łódź Voivodeship +Janusz A. Zajdel Award winners +An ammeter (abbreviation of Ampere meter) is an instrument used to measure the current in a circuit. Electric currents are measured in amperes (A), hence the name. For direct measurement, the ammeter is connected in series with the circuit in which the current is to be measured. An ammeter usually has low resistance so that it does not cause a significant voltage drop in the circuit being measured. + +Instruments used to measure smaller currents, in the milliampere or microampere range, are designated as milliammeters or microammeters. Early ammeters were laboratory instruments that relied on the Earth's magnetic field for operation. By the late 19th century, improved instruments were designed which could be mounted in any position and allowed accurate measurements in electric power systems. It is generally represented by letter 'A' in a circuit. + +History + +The relation between electric current, magnetic fields and physical forces was first noted by Hans Christian Ørsted in 1820, who observed a compass needle was deflected from pointing North when a current flowed in an adjacent wire. The tangent galvanometer was used to measure currents using this effect, where the restoring force returning the pointer to the zero position was provided by the Earth's magnetic field. This made these instruments usable only when aligned with the Earth's field. Sensitivity of the instrument was increased by using additional turns of wire to multiply the effect – the instruments were called "multipliers". + +The word rheoscope as a detector of electrical currents was coined by Sir Charles Wheatstone about 1840 but is no longer used to describe electrical instruments. The word makeup is similar to that of rheostat (also coined by Wheatstone) which was a device used to adjust the current in a circuit. Rheostat is a historical term for a variable resistance, though unlike rheoscope may still be encountered. + +Types + +Some instruments are panel meters, meant to be mounted on some sort of control panel. Of these, the flat, horizontal or vertical type is often called an edgewise meter. + +Moving-coil + +The D'Arsonval galvanometer is a moving coil ammeter. It uses magnetic deflection, where current passing through a coil placed in the magnetic field of a permanent magnet causes the coil to move. The modern form of this instrument was developed by Edward Weston, and uses two spiral springs to provide the restoring force. The uniform air gap between the iron core and the permanent magnet poles make the deflection of the meter linearly proportional to current. These meters have linear scales. Basic meter movements can have full-scale deflection for currents from about 25 microamperes to 10 milliamperes. + +Because the magnetic field is polarised, the meter needle acts in opposite directions for each direction of current. A DC ammeter is thus sensitive to which polarity it is connected in; most are marked with a positive terminal, but some have centre-zero mechanisms +and can display currents in either direction. A moving coil meter indicates the average (mean) of a varying current through it, +which is zero for AC. For this reason, moving-coil meters are only usable directly for DC, not AC. + +This type of meter movement is extremely common for both ammeters and other meters derived from them, such as voltmeters and ohmmeters. + +Moving magnet +Moving magnet ammeters operate on essentially the same principle as moving coil, except that the coil is mounted in the meter case, and a permanent magnet moves the needle. Moving magnet Ammeters are able to carry larger currents than moving coil instruments, often several tens of Amperes, because the coil can be made of thicker wire and the current does not have to be carried by the hairsprings. Indeed, some Ammeters of this type do not have hairsprings at all, instead using a fixed permanent magnet to provide the restoring force. + +Electrodynamic +An electrodynamic ammeter uses an electromagnet instead of the permanent magnet of the d'Arsonval movement. This instrument can respond to both alternating and direct current and also indicates true RMS for AC. See Wattmeter for an alternative use for this instrument. + +Moving-iron + +Moving iron ammeters use a piece of iron which moves when acted upon by the electromagnetic force of a fixed coil of wire. The moving-iron meter was invented by Austrian engineer Friedrich Drexler in 1884. +This type of meter responds to both direct and alternating currents (as opposed to the moving-coil ammeter, which works on direct current only). The iron element consists of a moving vane attached to a pointer, and a fixed vane, surrounded by a coil. As alternating or direct current flows through the coil and induces a magnetic field in both vanes, the vanes repel each other and the moving vane deflects against the restoring force provided by fine helical springs. The deflection of a moving iron meter is proportional to the square of the current. Consequently, such meters would normally have a nonlinear scale, but the iron parts are usually modified in shape to make the scale fairly linear over most of its range. Moving iron instruments indicate the RMS value of any AC waveform applied. Moving iron ammeters are commonly used to measure current in industrial frequency AC circuits. + +Hot-wire + +In a hot-wire ammeter, a current passes through a wire which expands as it heats. Although these instruments have slow response time and low accuracy, they were sometimes used in measuring radio-frequency current. +These also measure true RMS for an applied AC. + +Digital +In much the same way as the analogue ammeter formed the basis for a wide variety of derived meters, including voltmeters, the basic mechanism for a digital meter is a digital voltmeter mechanism, and other types of meter are built around this. + +Digital ammeter designs use a shunt resistor to produce a calibrated voltage proportional to the current flowing. This voltage is then measured by a digital voltmeter, through use of an analog-to-digital converter (ADC); the digital display is calibrated to display the current through the shunt. Such instruments are often calibrated to indicate the RMS value for a sine wave only, but many designs will indicate true RMS within limitations of the wave crest factor. + +Integrating + +There is also a range of devices referred to as integrating ammeters. +In these ammeters the current is summed over time, giving as a result the product of current and time; which is proportional to the electrical charge transferred with that current. These can be used for metering energy (the charge needs to be multiplied by the voltage to give energy) or for estimating the charge of a battery or capacitor. + +Picoammeter +A picoammeter, or pico ammeter, measures very low electric current, usually from the picoampere range at the lower end to the milliampere range at the upper end. Picoammeters are used where the current being measured is below the limits of sensitivity of other devices, such as multimeters. + +Most picoammeters use a "virtual short" technique and have several different measurement ranges that must be switched between to cover multiple decades of measurement. Other modern picoammeters use log compression and a "current sink" method that eliminates range switching and associated voltage spikes. +Special design and usage considerations must be observed in order to reduce leakage current which may swamp measurements such as special insulators and driven shields. Triaxial cable is often used for probe connections. + +Application + +Ammeters must be connected in series with the circuit to be measured. For relatively small currents (up to a few amperes), an ammeter may pass the whole of the circuit current. For larger direct currents, a shunt resistor carries most of the circuit current and a small, accurately-known fraction of the current passes through the meter movement. For alternating current circuits, a current transformer may be used to provide a convenient small current to drive an instrument, such as 1 or 5 amperes, while the primary current to be measured is much larger (up to thousands of amperes). The use of a shunt or current transformer also allows convenient location of the indicating meter without the need to run heavy circuit conductors up to the point of observation. In the case of alternating current, the use of a current transformer also isolates the meter from the high voltage of the primary circuit. A shunt provides no such isolation for a direct-current ammeter, but where high voltages are used it may be possible to place the ammeter in the "return" side of the circuit which may be at low potential with respect to earth. + +Ammeters must not be connected directly across a voltage source since their internal resistance is very low and excess current would flow. Ammeters are designed for a low voltage drop across their terminals, much less than one volt; the extra circuit losses produced by the ammeter are called its "burden" on the measured circuit(I). + +Ordinary Weston-type meter movements can measure only milliamperes at most, because the springs and practical coils can carry only limited currents. To measure larger currents, a resistor called a shunt is placed in parallel with the meter. The resistances of shunts is in the integer to fractional milliohm range. Nearly all of the current flows through the shunt, and only a small fraction flows through the meter. This allows the meter to measure large currents. Traditionally, the meter used with a shunt has a full-scale deflection (FSD) of , so shunts are typically designed to produce a voltage drop of when carrying their full rated current. + +To make a multi-range ammeter, a selector switch can be used to connect one of a number of shunts across the meter. It must be a make-before-break switch to avoid damaging current surges through the meter movement when switching ranges. + +A better arrangement is the Ayrton shunt or universal shunt, invented by William E. Ayrton, which does not require a make-before-break switch. It also avoids any inaccuracy because of contact resistance. In the figure, assuming for example, a movement with a full-scale voltage of 50 mV and desired current ranges of 10 mA, 100 mA, and 1 A, the resistance values would be: R1 = 4.5 ohms, R2 = 0.45 ohm, R3 = 0.05 ohm. And if the movement resistance is 1000 ohms, for example, R1 must be adjusted to 4.525 ohms. + +Switched shunts are rarely used for currents above 10 amperes. + +Zero-center ammeters are used for applications requiring current to be measured with both polarities, common in scientific and industrial equipment. Zero-center ammeters are also commonly placed in series with a battery. In this application, the charging of the battery deflects the needle to one side of the scale (commonly, the right side) and the discharging of the battery deflects the needle to the other side. A special type of zero-center ammeter for testing high currents in cars and trucks has a pivoted bar magnet that moves the pointer, and a fixed bar magnet to keep the pointer centered with no current. The magnetic field around the wire carrying current to be measured deflects the moving magnet. + +Since the ammeter shunt has a very low resistance, mistakenly wiring the ammeter in parallel with a voltage source will cause a short circuit, at best blowing a fuse, possibly damaging the instrument and wiring, and exposing an observer to injury. + +In AC circuits, a current transformer can be used to convert the large current in the main circuit into a smaller current more suited to a meter. Some designs of transformer are able to directly convert the magnetic field around a conductor into a small AC current, typically either or at full rated current, that can be easily read by a meter. In a similar way, accurate AC/DC non-contact ammeters have been constructed using Hall effect magnetic field sensors. A portable hand-held clamp-on ammeter is a common tool for maintenance of industrial and commercial electrical equipment, which is temporarily clipped over a wire to measure current. Some recent types have a parallel pair of magnetically soft probes that are placed on either side of the conductor. + +See also + +Clamp meter +Class of accuracy in electrical measurements +Electric circuit +Electrical measurements +Electrical current#Measurement +Electronics +List of electronics topics +Measurement category +Multimeter +Ohmmeter +Rheoscope +Voltmeter + +Notes + +References + +External links + + — from Lessons in Electric Circuits series main page + +Electrical meters +Electronic test equipment +Flow meters +Amanda Hesser (born 1971) is an American food writer, editor, cookbook author and entrepreneur. Most notably, she was the food editor of The New York Times Magazine, the editor of T Living, a quarterly publication of The New York Times, author of The Essential New York Times Cookbook which was a New York Times bestseller, and co-founder and CEO of Food52. + +Biography +After finishing her first book, in 1997, Hesser was hired as a food reporter for The New York Times where she wrote more than 750 stories. While at the Times, Hesser wrote about the influence of Costco on the wine industry, and how the Farmer Consumer Advisory Committee made decisions for the New York City Greenmarket. She was also among the first to write about Ferran Adrià of El Bulli in a major American publication. + +Hesser was involved in two cases of conflict of interest while working at the Times. In 2004, she awarded the restaurant Spice Market a three-star rating without disclosing that the year before, the restaurant's owner, Jean-Georges Vongerichten, had provided a complimentary jacket blurb for her book Cooking for Mr. Latte. In 2007, Hesser published a favorable review of Vegetable Harvest by Patricia Wells without noting that in 1999, Wells had provided a jacket blurb for Hesser's book The Cook and the Gardener. In both cases, the Times subsequently pointed out the conflicts of interest with editors' notes. + +While Hesser left the Times in March 2008 to focus on the development of Food52, she continued to write the "Recipe Redux" feature for the Times magazine until February 27, 2011. + +As co-founder and CEO of Food52, she has raised two rounds of investment from parties including Lerer Hippeau Ventures and Bertelsmann Digital Media Investments. Food52 has won numerous notable awards, including the James Beard Foundation Award for Publication of the Year (2012) and the International Association of Culinary Professionals Award for Best Website (2013). In February 2017, noting that 92 percent of the company was white, she and her co-founder Merrill Stubbs "issued a statement about the ways in which the company intended to redress a lack of racial equality in its workplace." By the following January, "they published a follow-up letter updating readers on the progress of their efforts, stating that their staff had been reduced to being 76 percent white." + +Hesser was featured in Food & Wine'''s 40 under 40 list, was named one of the 50 most influential women in food by Gourmet magazine, and had a cameo as herself in the film Julie & Julia. + +Hesser lives in Brooklyn Heights with her husband, Tad Friend, a staff writer for The New Yorker, and their two children. + +Bibliography + +BooksThe Cook and the Gardener (W. W. Norton & Company, 1999)Cooking for Mr. Latte: A Food Lover's Courtship, with Recipes (W. W. Norton & Company, 2004) [Collected Food Diary columns she wrote from 2000 to 2002]Eat, Memory: Great Writers at the Table, a Collection of Essays from the New York Times (W. W. Norton & Company, 2009) [Edited 26 previously published essays]The Essential New York Times Cookbook: Classic Recipes for a New Century (W. W. Norton & Company, 2010)The Food52 Cookbook: 140 Winning Recipes from Exceptional Home Cooks (William Morrow Cookbooks, 2011)The Food52 Cookbook, Volume 2: Seasonal Recipes from Our Kitchens to Yours (William Morrow Cookbooks, 2012)Food52 Genius Recipes: 100 Recipes That Will Change the Way You Cook (Ten Speed Press, 2015)Food52 Vegan: 60 Vegetable-Driven Recipes for Any Kitchen (Ten Speed Press, 2015)Food52 Baking: 60 Sensational Treats You Can Pull Off in a Snap (Ten Speed Press, 2015)Food52 A New Way to Dinner: A Playbook of Recipes and Strategies for the Week Ahead (Ten Speed Press, 2016)Food52 Mighty Salads: 60 New Ways to Turn Salad into Dinner (Ten Speed Press, 2017)Food52 Ice Cream and Friends: 60 Recipes and Riffs for Sorbets, Sandwiches, No-Churn Ice Creams, and More (Ten Speed Press, 2017)Food52 Any Night Grilling: 60 Ways to Fire Up Dinner (and More) (Ten Speed Press, 2018)Food52 Genius Desserts: 100 Recipes That Will Change the Way You Bake (Ten Speed Press, 2018) + +eBooks + "Food 52 Holiday Recipes & Party Planning Guide: A cookbook, instruction manual, and entertaining battle plan" (Open Air Publishing, 2011) + +Anthologized worksWomen Who Eat (2003)Best Food Writing (2002, 2004)The Art of Eating (2004)Alone in the Kitchen with an Eggplant (2007)Eat, Memory: Great Writers at the Table'' (2009) + +References + +External links + + +1972 births +Living people +American food writers +Women food writers +Women cookbook writers +People from Brooklyn Heights +American women chief executives +American company founders +American women company founders +International Association of Culinary Professionals award winners +21st-century American women +An anxiolytic (; also antipanic or anti-anxiety agent) is a medication or other intervention that reduces anxiety. This effect is in contrast to anxiogenic agents which increase anxiety. Anxiolytic medications are used for the treatment of anxiety disorders and their related psychological and physical symptoms. + +Nature of anxiety +Anxiety is a naturally-occurring emotion and response. When anxiety levels exceed the tolerability of a person, anxiety disorders may occur. People with anxiety disorders can exhibit fear responses, such as defensive behaviors, high levels of alertness, and negative emotions. Those with anxiety disorders may have concurrent psychological disorders, such as depression. Anxiety disorders are classified using six possible clinical assessments: + +Different types of anxiety disorders will share some general symptoms while having their own distinctive symptoms. This explains why people with different types of anxiety disorders will respond differently to different classes of anti-anxiety medications. + +Etiology +The etiology of anxiety disorder remains unknown. There are several contributing factors that are still yet to be proved to cause anxiety disorders. These factors include childhood anxiety, drug induction by central stimulant drugs, metabolic diseases or having depressive disorder. + +Medications +Anti-anxiety medication is any drug that can be taken or prescribed for the treatment of anxiety disorders, which may be mediated by neurotransmitters like norepinephrine, serotonin, dopamine, and gamma-aminobutyric acid (GABA) in the central nervous system. Anti-anxiety medication can be classified into six types according to their different mechanisms: antidepressants, benzodiazepines, azapirones, antiepileptics, antipsychotics, and beta blockers. + +Antidepressants include selective serotonin reuptake inhibitors (SSRIs), serotonin–norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCA), monoamine oxidase inhibitor (MAOI). SSRIs are used in all types of anxiety disorders while SNRIs are used for generalized anxiety disorder (GAD). Both of them are considered as first-line anti-anxiety medications. TCAs are second-line treatment as they cause more significant adverse effects when compared to the first-line treatment. Benzodiazepines are effective in emergent and short-term treatment of anxiety disorders due to their fast onset but carry the risk of dependence. Buspirone is indicated for GAD, which has much slower onset but with the advantage of less sedating and withdrawal effects. + +History +The first monoamine oxidase inhibitor (MAOI), iproniazid, was discovered accidentally when developing the new antitubercular drug isoniazid. The drug was found to induce euphoria and improve the patient's appetite and sleep quality. + +The first tricyclic antidepressant, imipramine, was originally developed and studied to be an antihistamine alongside other first-generation antihistamines of the time, such as promethazine. TCAs can increase the level of norepinephrine and serotonin by inhibiting their reuptake transport proteins. The majority of TCAs exert greater effect on norepinephrine, which leads to side effects like drowsiness and memory loss. + +In order to be more effective on serotonin agonism and avoid anticholinergic and antihistaminergic side effects, selective serotonin reuptake inhibitors (SSRI) were researched and introduced to treat anxiety disorders. The first SSRI, fluoxetine (Prozac), was discovered in 1974 and approved by FDA in 1987. After that, other SSRIs like sertraline (Zoloft), paroxetine (Paxil), and escitalopram (Lexapro) have entered the market. + +The first serotonin norepinephrine reuptake inhibitor (SNRI), venlafaxine (Effexor), entered the market in 1993. SNRIs can target serotonin and norepinephrine transporters while avoiding imposing significant effects on other adrenergic (α1, α2, and β), histamine (H1), muscarinic, dopamine, or postsynaptic serotonin receptors. + +Classifications +There are six groups of anti-anxiety medications available that have been proven to be clinically significant in treatment of anxiety disorders. The groups of medications are as follows. + +Antidepressants +Medications that are indicated for both anxiety disorders and depression. Selective serotonin reuptake inhibitors (SSRIs) and serotonin–norepinephrine reuptake inhibitors (SNRIs) are new generations of antidepressants. They have a much lower adverse effect profile than older antidepressants like monoamine oxidase inhibitors (MAOIs) and tricyclic antidepressant (TCAs). Therefore, SSRIs and SNRIs are now the first-line agent in treating long term anxiety disorders, given their applications and significance in all six types of disorders. + +Benzodiazepines +Benzodiazepines are used for acute anxiety and could be added along with current use of SSRIs to stabilize a treatment. Long-term use in treatment plans is not recommended. Different kinds of benzodiazepine will vary in its pharmacological profile, including its strength of effect and time taken for metabolism. The choice of the benzodiazepine will depend on the corresponding profiles. + +Benzodiazepines are used for emergent or short-term management. They are not recommended as the first-line anti-anxiety drugs, but they can be used in combination with SSRIs/SNRIs during the initial treatment stage. Indications include panic disorder, sleep disorders, seizures, acute behavioral disturbance, muscle spasm and premedication and sedation for procedures. + +Azapirones +Buspirone can be useful in GAD but not particularly effective in treating phobias, panic disorder or social anxiety disorders. It is a safer option for long-term use as it does not cause dependence like benzodiazepines. + +Antiepileptics + +Antiepileptics are rarely prescribed as an off-label treatment for anxiety disorders and post-traumatic stress disorders. There have been some suggestions that they may help with GAD, panic disorder and phobic symptoms but there is currently not enough research or conclusive data suggesting they are more effective than a placebo. + +Antipsychotics +Olanzapine and risperidone are atypical antipsychotics which are also effective in GAD and PTSD treatment. However, there is a higher chance of experiencing adverse effects than the other anti-anxiety medications. + +Beta-adrenoceptor antagonists +Propranolol is originally used for high blood pressure and heart diseases. It can also be used to treat anxiety with symptoms like tremor or increased heart rate. They work on the nervous system and alleviate the symptoms as a relief. Propranolol is also commonly used for public speaking when one is nervous. + +Mechanism of action + +Selective serotonin reuptake inhibitors (SSRI) and serotonin and norepinephrine reuptake inhibitors (SNRI) +Both SSRIs and SNRIs are reuptake inhibitors of a class of nerve signal transduction chemical called neurotransmitters. Serotonin and norepinephrine are neurotransmitters that are related to nervous control in mood regulation. The level of neurotransmitters are regulated by the nerve through reuptake to avoid accumulation of the neurotransmitter at the endings of nerve fiber. By reuptaking the produced neurotransmitter, the level will go back down and ready to go back up upon excitation from a new nerve signal. However the level of patients with anxiety disorders are usually low or their nerve fibers are insensitive to the neurotransmitters. SSRIs and SNRIs will then block the channel of reuptake and increase the level of the neurotransmitter. The nerve fibers will originally inhibit further production of neurotransmitters upon the increase. However the prolonged increase will eventually desensitize the nerve about the change in level. Therefore, the action of both SSRIs and SNRIs will take 4–6 weeks to exert their full effect. + +Benzodiazepine +Benzodiazepines bind selectively to the GABA receptor, which is the receptor protein found in the nervous system and is in control of the nervous response. Benzodiazepine will increase the entry of chloride ions into the cells by improving the binding between GABA and GABA receptors and then the better opening of the channel for chloride ion passage. The high level of chloride ion inside the nerve cells makes the nerve more difficult to depolarize and inhibit further nerve signal transduction. The excitability of the nerves then reduces and the nervous system slows down. Therefore, the drug can alleviate symptoms of anxiety disorder and make the person less nervous. + +Clinical use + +Selective serotonin reuptake inhibitors +Selective serotonin reuptake inhibitors (SSRIs) are a class of medications used in the treatment of depression, anxiety disorders, OCD and some personality disorders. SSRIs are the first-line anti-anxiety medications. Serotonin is one of the crucial neurotransmitters in mood enhancement, and increasing serotonin level produces an anti-anxiety effect. SSRIs increase the serotonin level in the brain by inhibiting serotonin uptake pumps on serotonergic systems, without interactions with other receptors and ion channels. SSRIs are beneficial in both acute response and long-term maintenance treatment for both depression and anxiety disorder. + +SSRIs can increase anxiety initially due to negative feedback through the serotonergic autoreceptors; for this reason a concurrent benzodiazepine can be used until the anxiolytic effect of the SSRI occurs. + +The SSRIs paroxetine and escitalopram are USFDA approved to treat generalized anxiety disorder. + +Therapeutic use + +Adverse effect +The common early side effects of SSRIs include nausea and loose stool, which can be solved by discontinuing the treatment. Headache, dizziness, insomnia are the common early side effects as well. + +Sexual dysfunction, anorgasmia, erectile dysfunction, and reduced libido are common adverse side effects of SSRIs. Sometimes they may persist after the cessation of treatment. + +Withdrawal symptoms like dizziness, headache and flu-like symptoms (fatigue/myalgia/loose stool) may occur if SSRI is stopped suddenly. The brain is incapable of upregulating the receptors to sufficient levels especially after discontinuation of the drugs with short half life like paroxetine. Both fluoxetine and its active metabolite have a long half life therefore it causes the least withdrawal symptoms. + +Serotonin–norepinephrine reuptake inhibitors +Serotonin–norepinephrine reuptake inhibitor (SNRIs) include venlafaxine and duloxetine drugs. Venlafaxine, in extended release form, and duloxetine, are indicated for the treatment of GAD. SNRIs are as effective as SSRIs in the treatment of anxiety disorders. + +Tricyclic antidepressants +Tricyclic antidepressants (TCAs) have anxiolytic effects; however, side effects are often more troubling or severe and overdose is dangerous. They are considered effective, but have generally been replaced by antidepressants that cause different adverse effects. Examples include imipramine, doxepin, amitriptyline, nortriptyline and desipramine. + +Therapeutic use + +Contraindication +TCAs may cause drug poisoning in patients with hypotension, cardiovascular diseases and arrhythmias. + +Tetracyclic antidepressants + +Mirtazapine has demonstrated anxiolytic effect comparable to SSRIs while rarely causing or exacerbating anxiety. Mirtazapine's anxiety reduction tends to occur significantly faster than SSRIs. + +Monoamine oxidase inhibitors +Monoamine oxidase inhibitors (MAOIs) are first-generation antidepressants effective for anxiety treatment but their dietary restrictions, adverse effect profile and availability of newer medications have limited their use. MAOIs include phenelzine, isocarboxazid and tranylcypromine. Pirlindole is a reversible MAOI that lacks dietary restriction. + +Barbiturates +Barbiturates are powerful anxiolytics but the risk of abuse and addiction is high. Many experts consider these drugs obsolete for treating anxiety but valuable for the short-term treatment of severe insomnia, though only after benzodiazepines or non-benzodiazepines have failed. + +Benzodiazepines +Benzodiazepines are prescribed to quell panic attacks. Benzodiazepines are also prescribed in tandem with an antidepressant for the latent period of efficacy associated with many ADs for anxiety disorder. There is risk of benzodiazepine withdrawal and rebound syndrome if BZDs are rapidly discontinued. Tolerance and dependence may occur. The risk of abuse in this class of medication is smaller than in that of barbiturates. Cognitive and behavioral adverse effects are possible. + +Benzodiazepines include: +alprazolam (Xanax), bromazepam, +chlordiazepoxide (Librium), +clonazepam (Klonopin), +diazepam (Valium), +lorazepam (Ativan), +oxazepam, +temazepam, and Triazolam. + +Therapeutic use + +Adverse effect +Benzodiazepines lead to central nervous system depression, resulting in common adverse effects like drowsiness, oversedation, light-headedness. Memory impairment can be a common adverse effect especially in elderly, hypersalivation, ataxia, slurred speech, psychomotor effects. + +Sympatholytics +Sympatholytics are a group of anti-hypertensives which inhibit activity of the sympathetic nervous system. Beta blockers reduce anxiety by decreasing heart rate and preventing shaking. Beta blockers include propranolol, oxprenolol, and metoprolol. The alpha-1 agonist prazosin could be effective for PTSD. The alpha-2 agonists clonidine and guanfacine have demonstrated both anxiolytic and anxiogenic effects. + +Miscellaneous + +Buspirone +Buspirone (Buspar) is a 5-HT1A receptor agonist used to treated generalized anxiety disorder. If an individual has taken a benzodiazepine, buspirone will be less effective. + +Pregabalin +Pregabalin (Lyrica) produces anxiolytic effect after one week of use comparable to lorazepam, alprazolam, and venlafaxine with more consistent psychic and somatic anxiety reduction. Unlike BZDs, it does not disrupt sleep architecture nor does it cause +cognitive or psychomotor impairment. + +Hydroxyzine +Hydroxyzine (Atarax) is an antihistamine originally approved for clinical use by the FDA in 1956. Hydroxyzine has a calming effect which helps ameliorate anxiety. Hydroxyzine efficacy is comparable to benzodiazepines in the treatment of generalized anxiety disorder. + +Phenibut +Phenibut (Anvifen, Fenibut, Noofen) is an anxiolytic used in Russia. Phenibut is a GABAB receptor agonist, as well as an antagonist at α2δ subunit-containing voltage-dependent calcium channels (VDCCs), similarly to gabapentinoids like gabapentin and pregabalin. The medication is not approved by the FDA for use in the United States, but is sold online as a supplement. + +Temgicoluril +Temgicoluril (Mebicar) is an anxiolytic produced in Latvia and used in Eastern Europe. Temgicoluril has an effect on the structure of limbic-reticular activity, particularly on the hypothalamus, as well as on all four basic neuromediator systems – γ aminobutyric acid (GABA), choline, serotonin and adrenergic activity. Temgicoluril decreases noradrenaline, increases serotonin, and exerts no effect on dopamine. + +Fabomotizole +Fabomotizole (Afobazole) is an anxiolytic drug launched in Russia in the early 2000s. Its mechanism of action is poorly-defined, with GABAergic, NGF and BDNF release promoting, MT1 receptor agonism, MT3 receptor antagonism, and sigma receptor agonism thought to have some involvement. + +Bromantane +Bromantane is a stimulant drug with anxiolytic properties developed in Russia during the late 1980s. Bromantane acts mainly by facilitating the biosynthesis of dopamine, through indirect genomic upregulation of relevant enzymes (tyrosine hydroxylase (TH) and aromatic L-amino acid decarboxylase (AAAD)). + +Emoxypine +Emoxypine is an antioxidant that is also a purported anxiolytic. Its chemical structure resembles that of pyridoxine, a form of vitamin B6. + +Menthyl isovalerate +Menthyl isovalerate is a flavoring food additive marketed as a sedative and anxiolytic drug in Russia under the name Validol. + +Racetams +Some racetam based drugs such as aniracetam can have an antianxiety effect. + +Alpidem +Alpidem is a nonbenzodiazepine anxiolytic with similar anxiolytic effectiveness as benzodiazepines but reduced sedation and cognitive, memory, and motor impairment. It was marketed briefly in France but was withdrawn from the market due to liver toxicity. + +Etifoxine +Etifoxine has similar anxiolytic effects as benzodiazepine drugs, but does not produce the same levels of sedation and ataxia. Further, etifoxine does not affect memory and vigilance, and does not induce rebound anxiety, drug dependence, or withdrawal symptoms. + +Alcohol +Alcohol is sometimes used as an anxiolytic by self-medication. fMRI can measure the anxiolytic effects of alcohol in the human brain. + +Alternatives to medication +Cognitive behavioral therapy (CBT) is an effective treatment for panic disorder, social anxiety disorder, generalized anxiety disorder, and obsessive–compulsive disorder, while exposure therapy is the recommended treatment for anxiety related phobias. Healthcare providers can guide those with anxiety disorder by referring them to self-help resources. Sometimes medication is combined with psychotherapy but research has not found a benefit of combined pharmacotherapy and psychotherapy versus monotherapy. + +If CBT is found ineffective, both the Canadian and American medical associations then suggest the use of medication. + +See also + +Categories + +References + +External links + + +Anxiety disorder treatment +Drug classes defined by psychological effects +Antipsychotics, also known as neuroleptics, are a class of psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but also in a range of other psychotic disorders. They are also the mainstay together with mood stabilizers in the treatment of bipolar disorder. + + +Prior research has shown that use of any antipsychotic is associated with smaller brain tissue volumes, including white matter reduction and that this brain shrinkage is dose dependent and time dependent. A more recent controlled trial suggests that second generation antipsychotics combined with intensive psychosocial therapy may potentially prevent pallidal brain volume loss in first episode psychosis. + + +The use of antipsychotics may result in many unwanted side effects such as involuntary movement disorders, gynecomastia, impotence, weight gain and metabolic syndrome. Long-term use can produce adverse effects such as tardive dyskinesia, tardive dystonia, and tardive akathisia. + +Prevention of these adverse effects is possible through concomitant medication strategies including use of beta-blockers. Currently, treatments for tardive diseases are not well established. + +First-generation antipsychotics (e.g. chlorpromazine), known as typical antipsychotics, were first introduced in the 1950s, and others were developed until the early 1970s. Second-generation antipsychotics, known as atypical antipsychotics, were introduced firstly with clozapine in the early 1970s followed by others (e.g. risperidone). Both generations of medication block receptors in the brain for dopamine, but atypicals tend to act on serotonin receptors as well. Neuroleptic, originating from (neuron) and (take hold of)—thus meaning "which takes the nerve"—refers to both common neurological effects and side effects. + +Medical uses +Antipsychotics are most frequently used for the following conditions: + Schizophrenia + Schizoaffective disorder most commonly in conjunction with either an antidepressant (in the case of the depressive subtype) or a mood stabiliser (in the case of the bipolar subtype). Antipsychotics can also be used as standalone mood stabiliser medications. + Bipolar disorder (acute mania and mixed episodes) may be treated with either typical or atypical antipsychotics, although atypical antipsychotics are usually preferred because they tend to have more favourable adverse effect profiles and, according to a recent meta-analysis, they tend to have a lower liability for causing conversion from mania to depression. + Psychotic depression. In this indication it is a common practice for the psychiatrist to prescribe a combination of an atypical antipsychotic and an antidepressant as this practice is best supported by the evidence. + Treatment resistant depression as an adjunct to standard antidepressant therapy. + +Antipsychotics are generally not recommended for treating behavioral problems associated with dementia, given that the risk of use tends to be greater than the potential benefit. The same can be said for insomnia, in which they are not recommended as first-line therapy. There are evidence-based indications for using antipsychotics in children (e.g. tic disorder, bipolar disorder, psychosis), but the use of antipsychotics outside of those contexts (e.g. to treat behavioral problems) warrants significant caution. + +Antipsychotics are used to treat tics associated with Tourette syndrome. Aripiprazole, an atypical antipsychotic, is used as add-on medication to ameliorate sexual dysfunction as a symptom of selective serotonin reuptake inhibitor antidepressants in women. Quetiapine is used to treat generalized anxiety disorder. + +Schizophrenia + +Antipsychotic drug treatment is a key component of schizophrenia treatment recommendations by the National Institute of Health and Care Excellence (NICE), the American Psychiatric Association, and the British Society for Psychopharmacology. The main aim of treatment with antipsychotics is to reduce the positive symptoms of psychosis, that include delusions and hallucinations. There is mixed evidence to support a significant impact of antipsychotic use on primary negative symptoms (such as apathy, lack of emotional affect, and lack of interest in social interactions) or on cognitive symptoms (memory impairments, reduced ability to plan and execute tasks). In general, the efficacy of antipsychotic treatment in reducing positive symptoms appears to increase with the severity of baseline symptoms. All antipsychotic medications work relatively the same way: by antagonizing D2 dopamine receptors. However, there are some differences when it comes to typical and atypical antipsychotics. For example, atypical antipsychotic medications have been seen to lower the neurocognitive impairment associated with schizophrenia more than conventional antipsychotics, although the reasoning and mechanics of this are still unclear to researchers. + +Applications of antipsychotic drugs in the treatment of schizophrenia include prophylaxis for those showing symptoms that suggest that they are at high risk of developing psychosis; treatment of first-episode psychosis; maintenance therapy (a form of prophylaxis, maintenance therapy aims to maintain therapeutic benefit and prevent symptom relapse); and treatment of recurrent episodes of acute psychosis. + +Prevention of psychosis and symptom improvement +Test batteries such as the PACE (Personal Assessment and Crisis Evaluation Clinic) and COPS (Criteria of Prodromal Syndromes), which measure low-level psychotic symptoms and cognitive disturbances, are used to evaluate people with early, low-level symptoms of psychosis. Test results are combined with family history information to identify patients in the "high-risk" group; they are considered to have a 20–40% risk of progression to frank psychosis within two years. These patients are often treated with low doses of antipsychotic drugs with the goal of reducing their symptoms and preventing progression to frank psychosis. While generally useful for reducing symptoms, clinical trials to date show little evidence that early use of antipsychotics improves long-term outcomes in those with prodromal symptoms, either alone or in combination with cognitive-behavioral therapy. + +First-episode psychosis +First-episode psychosis (FEP) is the first time that psychotic symptoms are presented. NICE recommends that all people presenting with first-episode psychosis be treated with both an antipsychotic drug and cognitive behavioral therapy (CBT). NICE further recommends that those expressing a preference for CBT alone be informed that combination treatment is more effective. A diagnosis of schizophrenia is not made at this time as it takes longer to be determined by both DSM-5 and ICD-11, and only around 60% of those presenting with a first episode of psychosis will later be diagnosed with schizophrenia. + +The conversion rate for a first episode of drug induced psychosis to bipolar disorder or schizophrenia is lower, with 30% of people converting to either bipolar disorder or schizophrenia. NICE makes no distinction between substance-induced psychosis and any other form of psychosis. The rate of conversion differs for different classes of drugs. + +Pharmacological options for the specific treatment of FEP have been discussed in recent reviews. The goals of treatment for FEP include reducing symptoms and potentially improving long-term treatment outcomes. Randomized clinical trials have provided evidence for the efficacy of antipsychotic drugs in achieving the former goal, with first-generation and second generation antipsychotics showing about equal efficacy. The evidence that early treatment has a favorable effect on long-term outcomes is equivocal. + +Recurrent psychotic episodes +Placebo-controlled trials of both first- and second-generation antipsychotic drugs consistently demonstrate the superiority of active drugs over placebos in suppressing psychotic symptoms. A large meta-analysis of 38 trials of antipsychotic drugs in schizophrenia with acute psychotic episodes showed an effect size of about 0.5. There is little or no difference in efficacy among approved antipsychotic drugs, including both first- and second-generation agents. The efficacy of such drugs is suboptimal. Few patients achieve complete resolution of symptoms. Response rates, calculated using various cutoff values for symptom reduction, are low, and their interpretation is complicated by high placebo response rates and selective publication of clinical trial results. + +Maintenance therapy +The majority of patients treated with an antipsychotic drug will experience a response within four weeks. The goals of continuing treatment are to maintain suppression of symptoms, prevent relapse, improve quality of life, and support engagement in psychosocial therapy. + +Maintenance therapy with antipsychotic drugs is clearly superior to placebo in preventing relapse but is associated with weight gain, movement disorders, and high dropout rates. A 3-year trial following persons receiving maintenance therapy after an acute psychotic episode found that 33% obtained long-lasting symptom reduction, 13% achieved remission, and only 27% experienced satisfactory quality of life. The effect of relapse prevention on long term outcomes is uncertain, as historical studies show little difference in long term outcomes before and after the introduction of antipsychotic drugs. + +While maintenance therapy clearly reduces the rate of relapses requiring hospitalization, a large observational study in Finland found that, in people that eventually discontinued antipsychotics, the risk of being hospitalized again for a mental health problem or dying increased the longer they were dispensed (and presumably took) antipsychotics prior to stopping therapy. If people did not stop taking antipsychotics, they remained at low risk for relapse and hospitalization compared to those that did. The authors speculated that the difference may be because the people that discontinued treatment after a longer time had more severe mental illness than those that discontinued antipsychotic therapy sooner. + +A significant challenge in the use of antipsychotic drugs for the prevention of relapse is the poor rate of adherence. In spite of the relatively high rates of adverse effects associated with these drugs, some evidence, including higher dropout rates in placebo arms compared to treatment arms in randomized clinical trials, suggests that most patients who discontinue treatment do so because of suboptimal efficacy. If someone experiences psychotic symptoms due to nonadherence, they may be compelled to receive treatment through a process called involuntary commitment, in which they can be forced to accept treatment (including antipsychotics). A person can also be committed to treatment outside of a hospital, called outpatient commitment. + +Antipsychotics in long-acting injectable (LAI), or "depot", form have been suggested as a method of decreasing medication nonadherence (sometimes also called non-compliance). NICE advises LAIs be offered to patients when preventing covert, intentional nonadherence is a clinical priority. LAIs are used to ensure adherence in outpatient commitment. A meta-analysis found that LAIs resulted in lower rates of rehospitalization with a hazard ratio of 0.83; however, these results were not statistically significant (the 95% confidence interval was 0.62 to 1.11). + +Bipolar disorder + +Antipsychotics are routinely used, often in conjunction with mood stabilisers such as lithium/valproate, as a first-line treatment for manic and mixed episodes associated with bipolar disorder. The reason for this combination is the therapeutic delay of the aforementioned mood stabilisers (for valproate therapeutic effects are usually seen around five days after treatment is commenced whereas lithium usually takes at least a week before the full therapeutic effects are seen) and the comparatively rapid antimanic effects of antipsychotic drugs. The antipsychotics have a documented efficacy when used alone in acute mania/mixed episodes. + +At least five atypical antipsychotics (lumateperone, cariprazine, lurasidone, olanzapine, and quetiapine) have also been found to possess efficacy in the treatment of bipolar depression as a monotherapy, whereas only olanzapine and quetiapine have been proven to be effective broad-spectrum (i.e. against all three types of relapse—manic, mixed and depressive) prophylactic (or maintenance) treatments in patients with bipolar disorder. A recent Cochrane review also found that olanzapine had a less favourable risk/benefit ratio than lithium as a maintenance treatment for bipolar disorder. + +The American Psychiatric Association and the UK National Institute for Health and Care Excellence recommend antipsychotics for managing acute psychotic episodes in schizophrenia or bipolar disorder, and as a longer-term maintenance treatment for reducing the likelihood of further episodes. They state that response to any given antipsychotic can be variable so that trials may be necessary, and that lower doses are to be preferred where possible. A number of studies have looked at levels of "compliance" or "adherence" with antipsychotic regimes and found that discontinuation (stopping taking them) by patients is associated with higher rates of relapse, including hospitalization. + +Dementia +Psychosis and agitation develop in as many as 80 percent of people living in nursing homes. Despite a lack of FDA approval and black-box warnings, atypical antipsychotics are very often prescribed to people with dementia. An assessment for an underlying cause of behavior is needed before prescribing antipsychotic medication for symptoms of dementia. Antipsychotics in old age dementia showed a modest benefit compared to placebo in managing aggression or psychosis, but this is combined with a fairly large increase in serious adverse events. Thus, antipsychotics should not be used routinely to treat dementia with aggression or psychosis, but may be an option in a few cases where there is severe distress or risk of physical harm to others. Psychosocial interventions may reduce the need for antipsychotics. In 2005, the FDA issued an advisory warning of an increased risk of death when atypical antipsychotics are used in dementia. In the subsequent 5 years, the use of atypical antipsychotics to treat dementia decreased by nearly 50%. + +Major depressive disorder +A number of atypical antipsychotics have some benefits when used in addition to other treatments in major depressive disorder. Aripiprazole, quetiapine extended-release, and olanzapine (when used in conjunction with fluoxetine) have received the Food and Drug Administration (FDA) labelling for this indication. There is, however, a greater risk of side effects with their use compared to using traditional antidepressants. The greater risk of serious side effects with antipsychotics is why, e.g., quetiapine was denied approval as monotherapy for major depressive disorder or generalized anxiety disorder, and instead was only approved as an adjunctive treatment in combination with traditional antidepressants. + +Other +Besides the above uses antipsychotics may be used for obsessive–compulsive disorder, post-traumatic stress disorder, personality disorders, Tourette syndrome, autism and agitation in those with dementia. Evidence however does not support the use of atypical antipsychotics in eating disorders or personality disorder. The atypical antipsychotic risperidone may be useful for obsessive–compulsive disorder. The use of low doses of antipsychotics for insomnia, while common, is not recommended as there is little evidence of benefit as well as concern regarding adverse effects. Some of the more serious adverse effects may also occur at the low doses used, such as dyslipidemia and neutropenia, and a recent network meta-analysis of 154 double-blind, randomized controlled trials of drug therapies vs. placebo for insomnia in adults found that quetiapine did not demonstrated any short-term benefits in sleep quality. Low dose antipsychotics may also be used in treatment of impulse-behavioural and cognitive-perceptual symptoms of borderline personality disorder. Despite the lack of evidence supporting the benefit of antipsychotics in people with personality disorders, 1 in 4 who do not have a serious mental illness are prescribed them in UK primary care. Many people receive these medication for over a year, contrary to NICE guidelines. + +In children they may be used in those with disruptive behavior disorders, mood disorders and pervasive developmental disorders or intellectual disability. Antipsychotics are only weakly recommended for Tourette syndrome, because although they are effective, side effects are common. The situation is similar for those on the autism spectrum. +Much of the evidence for the off-label use of antipsychotics (for example, for dementia, OCD, PTSD, personality disorders, Tourette's) was of insufficient scientific quality to support such use, especially as there was strong evidence of increased risks of stroke, tremors, significant weight gain, sedation, and gastrointestinal problems. A UK review of unlicensed usage in children and adolescents reported a similar mixture of findings and concerns. A survey of children with pervasive developmental disorder found that 16.5% were taking an antipsychotic drug, most commonly for irritability, aggression, and agitation. Both risperidone and aripiprazole have been approved by the US FDA for the treatment of irritability in autistic children and adolescents. A review in the UK found that the use of antipsychotics in England doubled between 2000 and 2019. Children were prescribed antipsychotics for conditions for which there is no approval, such as autism. + +Aggressive challenging behavior in adults with intellectual disability is often treated with antipsychotic drugs despite lack of an evidence base. A recent randomized controlled trial, however, found no benefit over placebo and recommended that the use of antipsychotics in this way should no longer be regarded as an acceptable routine treatment. + +Antipsychotics may be an option, together with stimulants, in people with ADHD and aggressive behavior when other treatments have not worked. They have not been found to be useful for the prevention of delirium among those admitted to hospital. + +Typicals vs atypicals +It is unclear whether the atypical (second-generation) antipsychotics offer advantages over older, first generation antipsychotics. Amisulpride, olanzapine, risperidone and clozapine may be more effective but are associated with greater side effects. Typical antipsychotics have equal drop-out and symptom relapse rates to atypicals when used at low to moderate dosages. + +Clozapine is an effective treatment for those who respond poorly to other drugs ("treatment-resistant" or "refractory" schizophrenia), but it has the potentially serious side effect of agranulocytosis (lowered white blood cell count) in less than 4% of people. + +Due to bias in the research the accuracy of comparisons of atypical antipsychotics is a concern. + +In 2005, a US government body, the National Institute of Mental Health published the results of a major independent study (the CATIE project). No other atypical studied (risperidone, quetiapine, and ziprasidone) did better than the typical perphenazine on the measures used, nor did they produce fewer adverse effects than the typical antipsychotic perphenazine, although more patients discontinued perphenazine owing to extrapyramidal effects compared to the atypical agents (8% vs. 2% to 4%). + +Atypical antipsychotics do not appear to lead to improved rates of medication adherence compared to typical antipsychotics. + +Many researchers question the first-line prescribing of atypicals over typicals, and some even question the distinction between the two classes. In contrast, other researchers point to the significantly higher risk of tardive dyskinesia and other extrapyramidal symptoms with the typicals and for this reason alone recommend first-line treatment with the atypicals, notwithstanding a greater propensity for metabolic adverse effects in the latter. The UK government organization NICE recently revised its recommendation favoring atypicals, to advise that the choice should be an individual one based on the particular profiles of the individual drug and on the patient's preferences. + +The re-evaluation of the evidence has not necessarily slowed the bias toward prescribing the atypicals. + +Adverse effects + +Generally, more than one antipsychotic drug should not be used at a time because of increased adverse effects. + +Some atypicals are associated with considerable weight gain, diabetes and the risk of metabolic syndrome. Unwanted side effects cause people to stop treatment, resulting in relapses. +Risperidone (atypical) has a similar rate of extrapyramidal symptoms to haloperidol (typical). A rare but potentially lethal condition of neuroleptic malignant syndrome (NMS) has been associated with the use of antipsychotics. Through its early recognition, and timely intervention rates have declined. However, an awareness of the syndrome is advised to enable intervention. Another less rare condition of tardive dyskinesia can occur due to long-term use of antipsychotics, developing after months or years of use. It is more often reported with use of typical antipsychotics. Very rarely antipsychotics may cause tardive psychosis. + +Clozapine is associated with side effects that include weight gain, tiredness, and hypersalivation. More serious adverse effects include seizures, NMS, neutropenia, and agranulocytosis (lowered white blood cell count) and its use needs careful monitoring. + +Clozapine is also associated with thromboembolism (including pulmonary embolism), myocarditis, and cardiomyopathy. A systematic review of clozapine-associated pulmonary embolism indicates that this adverse effect can often be fatal, and that it has an early onset, and is dose-dependent. The findings advised the consideration of using a prevention therapy for venous thromboembolism after starting treatment with clozapine, and continuing this for six months. Constipation is three times more likely to occur with the use of clozapine, and severe cases can lead to ileus and bowel ischemia resulting in many fatalities. Very rare clozapine adverse effects include periorbital edema due to several possible mechanisms (e.g. inhibition of platelet-derived growth factor receptors leading to increased vascular permeability, antagonism of renal dopamine receptors with electrolyte and fluid imbalance and immune-mediated hypersensitivity reactions). + +However, the risk of serious adverse effects from clozapine is low, and there are the beneficial effects to be gained of a reduced risk of suicide, and aggression. Typical antipsychotics and atypical risperidone can have a side effect of sexual dysfunction. Clozapine, olanzapine, and quetiapine are associated with beneficial effects on sexual functioning helped by various psychotherapies. + +By rate +Common (≥ 1% and up to 50% incidence for most antipsychotic drugs) adverse effects of antipsychotics include: + Dysphoria and apathy (due to dopamine receptor blockade) + Sedation (particularly common with asenapine, clozapine, olanzapine, quetiapine, chlorpromazine and zotepine) + Headaches + Dizziness + Diarrhea + Anxiety + Extrapyramidal side effects (particularly common with first-generation antipsychotics), which include: +- Akathisia, an often distressing sense of inner restlessness. +- Dystonia, an abnormal muscle contraction +- Pseudoparkinsonism, symptoms that are similar to what people with Parkinson's disease experience, including tremulousness and drooling + Hyperprolactinaemia (rare for those treated with clozapine, quetiapine and aripiprazole), which can cause: +- Galactorrhoea, the unusual secretion of breast milk. +- Gynaecomastia, abnormal growth of breast tissue +- Sexual dysfunction (in both sexes) +- Osteoporosis + Orthostatic hypotension + Weight gain (particularly prominent with clozapine, olanzapine, quetiapine and zotepine) + Anticholinergic side-effects (common for olanzapine, clozapine; less likely on risperidone) such as: +- Blurred vision +- Constipation +- Dry mouth (although hypersalivation may also occur) +- Reduced perspiration + Tardive dyskinesia appears to be more frequent with high-potency first-generation antipsychotics, such as haloperidol, and tends to appear after chronic and not acute treatment. It is characterized by slow (hence the tardive) repetitive, involuntary and purposeless movements, most often of the face, lips, legs, or torso, which tend to resist treatment and are frequently irreversible. The rate of appearance of TD is about 5% per year of use of antipsychotic drug (whatever the drug used) + breast cancer: a systematic review and meta-analysis of observational studies with over 2 million individuals estimated an association between antipsychotic use and breast cancer by over 30%. + +Rare/Uncommon (<1% incidence for most antipsychotic drugs) adverse effects of antipsychotics include: + Blood dyscrasias (e.g., agranulocytosis, leukopenia, and neutropaenia), which is more common in patients on clozapine. + Metabolic syndrome and other metabolic problems such as type II diabetes mellitus — particularly common with clozapine, olanzapine and zotepine. In American studies African Americans appeared to be at a heightened risk for developing type II diabetes mellitus. Evidence suggests that females are more sensitive to the metabolic side effects of first-generation antipsychotic drugs than males. Metabolic adverse effects appear to be mediated by the following mechanisms: +- Causing weight gain by antagonizing the histamine H1 and serotonin 5-HT2C receptors and perhaps by interacting with other neurochemical pathways in the central nervous system. + Neuroleptic malignant syndrome, a potentially fatal condition characterized by: +- Autonomic instability, which can manifest with tachycardia, nausea, vomiting, diaphoresis, etc. +- Hyperthermia — elevated body temperature. +- Mental status change (confusion, hallucinations, coma, etc.) +- Muscle rigidity +- Laboratory abnormalities (e.g., elevated creatine kinase, reduced iron plasma levels, electrolyte abnormalities, etc.) + Pancreatitis + QT interval prolongation — more prominent in those treated with amisulpride, pimozide, sertindole, thioridazine and ziprasidone. + Torsades de pointes + Seizures, particularly in people treated with chlorpromazine and clozapine. + Thromboembolism + Myocardial infarction + Stroke + Pisa syndrome + +Long-term effects + +Some studies have found decreased life expectancy associated with the use of antipsychotics, and argued that more studies are needed. Antipsychotics may also increase the risk of early death in individuals with dementia. Antipsychotics typically worsen symptoms in people with depersonalisation disorder. Antipsychotic polypharmacy (prescribing two or more antipsychotics at the same time for an individual) is a common practice but not evidence-based or recommended, and there are initiatives to curtail it. Similarly, the use of excessively high doses (often the result of polypharmacy) continues despite clinical guidelines and evidence indicating that it is usually no more effective but is usually more harmful. A meta-analysis of observational studies with over two million individuals has suggested a moderate association of antipsychotic use with breast cancer. + +Loss of grey matter and other brain structural changes over time are observed amongst people diagnosed with schizophrenia. Meta-analyses of the effects of antipsychotic treatment on grey matter volume and the brain's structure have reached conflicting conclusions. A 2012 meta-analysis concluded that grey matter loss is greater in patients treated with first generation antipsychotics relative to those treated with atypicals, and hypothesized a protective effect of atypicals as one possible explanation. A second meta-analysis suggested that treatment with antipsychotics was associated with increased grey matter loss. Animal studies found that monkeys exposed to both first- and second-generation antipsychotics experience significant reduction in brain volume, resulting in an 8-11% reduction in brain volume over a 17–27 month period. + +The National Association of State Mental Health Program Directors said that antipsychotics are not interchangeable and it is recommend including trying at least one weight-neutral treatment for those patients with potential metabolic issues. + +Subtle, long-lasting forms of akathisia are often overlooked or confused with post-psychotic depression, in particular when they lack the extrapyramidal aspect that psychiatrists have been taught to expect when looking for signs of akathisia. + +Adverse effect on cognitive function and increased risk of death in people with dementia along with worsening of symptoms has been described in the literature. + +Discontinuation + +The British National Formulary recommends a gradual withdrawal when discontinuing antipsychotics to avoid acute withdrawal syndrome or rapid relapse. Symptoms of withdrawal commonly include nausea, vomiting, and loss of appetite. Other symptoms may include restlessness, increased sweating, and trouble sleeping. Less commonly there may be a feeling of the world spinning, numbness, or muscle pains. Symptoms generally resolve after a short period of time. + +There is tentative evidence that discontinuation of antipsychotics can result in psychosis. It may also result in recurrence of the condition that is being treated. Rarely tardive dyskinesia can occur when the medication is stopped. + +Unexpected psychotic episodes have been observed in patients withdrawing from clozapine. This is referred to as supersensitivity psychosis, not to be equated with tardive dyskinesia. + +Tardive dyskinesia may abate during withdrawal from the antipsychotic agent, or it may persist. + +Withdrawal effects may also occur when switching a person from one antipsychotic to another, (it is presumed due to variations of potency and receptor activity). Such withdrawal effects can include cholinergic rebound, an activation syndrome, and motor syndromes including dyskinesias. These adverse effects are more likely during rapid changes between antipsychotic agents, so making a gradual change between antipsychotics minimises these withdrawal effects. The British National Formulary recommends a gradual withdrawal when discontinuing antipsychotic treatment to avoid acute withdrawal syndrome or rapid relapse. The process of cross-titration involves gradually increasing the dose of the new medication while gradually decreasing the dose of the old medication. + +City and Hackney Clinical Commissioning Group found more than 1,000 patients in their area in July 2019 who had not had regular medication reviews or health checks because they were not registered as having serious mental illness. On average they had been taking these drugs for six years. If this is typical of practice in England more than 100,000 patients are probably in the same position. + +List of agents + +Clinically used antipsychotic medications are listed below by drug group. Trade names appear in parentheses. A 2013 review has stated that the division of antipsychotics into first and second generation is perhaps not accurate. + +Notes: + +† indicates drugs that are no longer (or were never) marketed in English-speaking countries. + +‡ denotes drugs that are no longer (or were never to begin with) marketed in the United States. Some antipsychotics are not firmly placed in either first-generation or second-generation classes. + +# denotes drugs that have been withdrawn worldwide. + +First-generation (typical) + +Butyrophenones + + Benperidol‡ + Bromperidol† + Droperidol‡ + Haloperidol + Moperone (discontinued)† + Pipamperone (discontinued)† + Timiperone † + +Diphenylbutylpiperidines + Fluspirilene ‡ + Penfluridol ‡ + Pimozide + +Phenothiazines + + Acepromazine † — although it is mostly used in veterinary medicine. + Chlorpromazine