text:
April 17

Pre-1600

 * 1080 – Harald III of Denmark dies and is succeeded by Canute IV, who would later be the first Dane to be canonized.
 * 1349 – The rule of the Bavand dynasty in Mazandaran is brought to an end by the murder of Hasan II.
 * 1362 – Kaunas Castle falls to the Teutonic Order after a month-long siege.
 * 1492 – Spain and Christopher Columbus sign the Capitulations of Santa Fe for his voyage to Asia to acquire spices.
 * 1521 – Trial of Martin Luther over his teachings begins during the assembly of the Diet of Worms. Initially intimidated, he asks for time to reflect before answering and is given a stay of one day.
 * 1524 – Giovanni da Verrazzano reaches New York harbor.

1601–1900

 * 1797 – Sir Ralph Abercromby attacks San Juan, Puerto Rico, in what would be one of the largest invasions of the Spanish territories in the Americas.
 * 1797 – Citizens of Verona begin an unsuccessful eight-day rebellion against the French occupying forces.
 * 1861 – The state of Virginia's secession convention votes to secede from the United States; Virginia later becomes the eighth state to join the Confederate States of America.
 * 1863 – American Civil War: Grierson's Raid begins: Troops under Union Army Colonel Benjamin Grierson attack central Mississippi.
 * 1864 – American Civil War: The Battle of Plymouth begins: Confederate forces attack Plymouth, North Carolina.
 * 1869 – Morelos is admitted as the 27th state of Mexico.
 * 1876 – Catalpa rescue: The rescue of six Fenian prisoners from Fremantle Prison in Western Australia.
 * 1895 – The Treaty of Shimonoseki between China and Japan is signed. This marks the end of the First Sino-Japanese War, and the defeated Qing Empire is forced to renounce its claims on Korea and to concede the southern portion of the Fengtian province, Taiwan and the Penghu to Japan.

1901–present

 * 1905 – The Supreme Court of the United States decides Lochner v. New York, which holds that the "right to free contract" is implicit in the due process clause of the Fourteenth Amendment to the United States Constitution.
 * 1907 – The Ellis Island immigration center processes 11,747 people, more than on any other day.
 * 1912 – Russian troops open fire on striking goldfield workers in northeast Siberia, killing at least 150.
 * 1931 – After negotiations between Catalan and Spanish provisional governments, the Catalan Republic proclaimed in April 14 becomes the Generalitat de Catalunya, the autonomous government of Catalonia within the Spanish Republic.
 * 1941 – World War II: The Axis powers invasion of Yugoslavia is completed when it signs an armistice with Germany and Italy.
 * 1942 – French prisoner of war General Henri Giraud escapes from his castle prison in Königstein Fortress.
 * 1944 – Forces of the Communist-controlled Greek People's Liberation Army attack the smaller National and Social Liberation resistance group, which surrenders. Its leader Dimitrios Psarros is murdered.
 * 1945 – World War II: Montese, Italy, is liberated from Nazi forces.
 * 1945 – Historian Tran Trong Kim is appointed the Prime Minister of the Empire of Vietnam.
 * 1946 – The last French troops are withdrawn from Syria.
 * 1951 – The Peak District becomes the United Kingdom's first National Park.
 * 1961 – Bay of Pigs Invasion: A group of Cuban exiles financed and trained by the CIA lands at the Bay of Pigs in Cuba with the aim of ousting Fidel Castro.
 * 1969 – Sirhan Sirhan is convicted of assassinating Robert F. Kennedy.
 * 1969 – Communist Party of Czechoslovakia chairman Alexander Dubček is deposed.
 * 1970 – Apollo program: The damaged Apollo 13 spacecraft returns to Earth safely.
 * 1971 – The Provisional Government of Bangladesh is formed.
 * 1975 – The Cambodian Civil War ends. The Khmer Rouge captures the capital Phnom Penh and Cambodian government forces surrender.
 * 1978 – Mir Akbar Khyber is assassinated, provoking the Saur Revolution in Afghanistan.
 * 1982 – Constitution Act, 1982 Patriation of the Canadian constitution in Ottawa by Proclamation of Elizabeth II, Queen of Canada.
 * 1986 – An alleged state of war lasting 335 years between the Netherlands and the Isles of Scilly declared peace bringing an end to any hypothetical war that may have been legally considered to exist.
 * 1992 – The Katina P is deliberately run aground off Maputo, Mozambique, and 60,000 tons of crude oil spill into the ocean.
 * 1998 – Space Shuttle Columbia is launched on STS-90, the final Spacelab mission.
 * 2003 – Anneli Jäätteenmäki takes office as the first female prime minister of Finland.
 * 2006 – A Palestinian suicide bomber detonates an explosive device in a Tel Aviv restaurant, killing 11 people and injuring 70.
 * 2013 – An explosion at a fertilizer plant in the city of West, Texas, kills 15 people and injures 160 others.
 * 2014 – NASA's Kepler space telescope confirms the discovery of the first Earth-size planet in the habitable zone of another star.
 * 2021 – The funeral of Prince Philip, Duke of Edinburgh, takes place at St George's Chapel, Windsor Castle.

Pre-1600

 * 1277 – Michael IX Palaiologos, Byzantine emperor (d. 1320)
 * 1455 – Andrea Gritti, Doge of Venice (d. 1538)
 * 1497 – Pedro de Valdivia, Spanish conquistador, conquered northern Chile (d. 1553)
 * 1573 – Maximilian I, Elector of Bavaria (d. 1651)
 * 1586 – John Ford, English poet and playwright (d. 1639)
 * 1598 – Giovanni Battista Riccioli, Italian priest and astronomer (d. 1671)

1601–1900

 * 1620 – Marguerite Bourgeoys, French-Canadian nun and saint, founded the Congregation of Notre Dame of Montreal (d. 1700)
 * 1635 – Edward Stillingfleet, British theologian and scholar (d. 1699)
 * 1683 – Johann David Heinichen, German composer and theorist (d. 1729)
 * 1710 – Henry Erskine, 10th Earl of Buchan, Scottish politician (d. 1767)
 * 1734 – Taksin, King of Thailand (d. 1782)
 * 1741 – Samuel Chase, American lawyer and jurist (d. 1811)
 * 1750 – François de Neufchâteau, French academic and politician, French Minister of the Interior (d. 1828)
 * 1756 – Dheeran Chinnamalai, Indian commander (d. 1805)
 * 1766 – Collin McKinney, American surveyor, merchant, and politician (d. 1861)
 * 1794 – Carl Friedrich Philipp von Martius, German botanist and explorer (d. 1868)
 * 1798 – Étienne Bobillier, French mathematician and academic (d. 1840)
 * 1799 – Eliza Acton, English food writer and poet (d. 1859)
 * 1814 – Josif Pančić, Serbian botanist and academic (d. 1888)
 * 1816 – Thomas Hazlehurst, English architect and philanthropist (d. 1876)
 * 1820 – Alexander Cartwright, American firefighter and (disputed) inventor of baseball (d. 1892)
 * 1833 – Jean-Baptiste Accolay, Belgian violinist, composer, and conductor (d. 1900)
 * 1837 – J. P. Morgan, American banker and financier, founded J.P. Morgan & Co. (d. 1913)
 * 1842 – Maurice Rouvier, French businessman and politician, 53rd Prime Minister of France (d. 1911)
 * 1849 – William R. Day, American jurist and politician, 36th United States Secretary of State (d. 1923)
 * 1852 – Cap Anson, American baseball player and manager (d. 1922)
 * 1863 – Augustus Edward Hough Love, English mathematician and theorist (d. 1940)
 * 1865 – Ursula Ledóchowska, Polish-Austrian nun and saint, founded the Congregation of the Ursulines of the Agonizing Heart of Jesus (d. 1939)
 * 1866 – Ernest Starling, English physiologist and academic (d. 1927)
 * 1875 – Aleksander Tõnisson, Estonian general and politician, 5th Estonian Minister of War (d. 1941)
 * 1877 – Matsudaira Tsuneo, Japanese diplomat (d. 1949)
 * 1878 – Emil Fuchs, German-American lawyer and businessman (d. 1961)
 * 1878 – Demetrios Petrokokkinos, Greek tennis player (d. 1942)
 * 1879 – Henri Tauzin, French hurdler (d. 1918)
 * 1882 – Artur Schnabel, Polish pianist and composer (d. 1951)
 * 1888 – Herms Niel, German soldier, trombonist, and composer (d. 1954)
 * 1891 – George Adamski, Polish-American ufologist and author (d. 1965)
 * 1895 – Robert Dean Frisbie, American soldier and author (d. 1948)
 * 1896 – Señor Wences, Spanish-American ventriloquist (d. 1999)
 * 1897 – Nisargadatta Maharaj, Indian philosopher and educator (d. 1981)
 * 1897 – Thornton Wilder, American novelist and playwright (d. 1975)
 * 1897 – Edouard Wyss-Dunant, Swiss physician and mountaineer (d. 1983)
 * 1899 – Aleksander Klumberg, Estonian decathlete and coach (d. 1958)

1901–present

 * 1903 – Nicolas Nabokov, Russian-American composer and educator (d. 1978)
 * 1903 – Gregor Piatigorsky, Ukrainian-American cellist and educator (d. 1976)
 * 1903 – Morgan Taylor, American hurdler and coach (d. 1975)
 * 1905 – Louis Jean Heydt, American journalist and actor (d. 1960)
 * 1905 – Arthur Lake, American actor (d. 1987)
 * 1906 – Sidney Garfield, American physician, co-founded Kaiser Permanente (d. 1984)
 * 1909 – Alain Poher, French politician, President of France (d. 1996)
 * 1910 – Evangelos Averoff, Greek historian and politician, Greek Minister of Defence (d. 1990)
 * 1910 – Ivan Goff, Australian screenwriter and producer (d. 1999)
 * 1910 – Helenio Herrera, French footballer and manager (d. 1997)
 * 1911 – Hervé Bazin, French author and poet (d. 1996)
 * 1911 – Lester Rodney, American soldier and journalist (d. 2009)
 * 1912 – Marta Eggerth, Hungarian-American actress and singer (d. 2013)
 * 1914 – George Davis, American art director (d. 1984)
 * 1914 – Mac Raboy, American illustrator (d. 1967)
 * 1915 – Martin Clemens, Scottish soldier (d. 2009)
 * 1915 – Joe Foss, American general and politician, 20th Governor of South Dakota (d. 2003)
 * 1915 – Regina Ghazaryan, Armenian painter (d. 1999)
 * 1916 – Win Maung, 3rd President of Union of Myanmar (d. 1989)
 * 1916 – A. Thiagarajah, Sri Lankan educator and politician (d. 1981)
 * 1916 – Sirimavo Bandaranaike, Prime Minister of Sri Lanka, world's first female prime minister (d. 2000)
 * 1918 – William Holden, American actor (d. 1981)
 * 1919 – Gilles Lamontagne, Canadian lieutenant and politician, 24th Lieutenant Governor of Quebec (d. 2016)
 * 1919 – Chavela Vargas, Costa Rican-Mexican singer-songwriter and actress (d. 2012)
 * 1920 – Edmonde Charles-Roux, French journalist and author (d. 2016)
 * 1923 – Lindsay Anderson, English actor, director, and screenwriter (d. 1994)
 * 1923 – Solly Hemus, American baseball player, coach, and manager (d. 2017)
 * 1923 – Neville McNamara, Australian air marshal (d. 2014)
 * 1923 – Gianni Raimondi, Italian lyric tenor (d. 2008)
 * 1923 – Harry Reasoner, American soldier and journalist (d. 1991)
 * 1924 – Kenneth Norman Jones, Australian public servant (d. 2022)
 * 1924 – Donald Richie, American-Japanese author and critic (d. 2013)
 * 1925 – René Moawad, Lebanese lawyer and politician, 13th President of Lebanon (d. 1989)
 * 1926 – Joan Lorring, British actress (d. 2014)
 * 1926 – Gerry McNeil, Canadian ice hockey player and manager (d. 2004)
 * 1927 – Margot Honecker, East German politician and First Lady (d. 2016)
 * 1928 – Victor Lownes, American businessman (d. 2017)
 * 1928 – Cynthia Ozick, American short story writer, novelist, and essayist
 * 1928 – Heinz Putzl, Austrian fencer
 * 1928 – Fabien Roy, Canadian accountant and politician (d. 2023)
 * 1929 – James Last, German-American bassist, composer, and bandleader (d. 2015)
 * 1930 – Chris Barber, English trombonist and bandleader (d. 2021)
 * 1931 – John Barrett, English tennis player and sportscaster
 * 1931 – Malcolm Browne, American journalist and photographer (d. 2012)
 * 1934 – Don Kirshner, American songwriter and producer (d. 2011)
 * 1934 – Peter Morris, Australian-English surgeon and academic (d. 2022)
 * 1935 – Bud Paxson, American broadcaster, founded Home Shopping Network and Pax TV (d. 2015)
 * 1936 – Urs Wild, Swiss chemist (d. 2022)
 * 1937 – Ronald Hamowy, Canadian historian and academic (d. 2012)
 * 1937 – Ferdinand Piëch, Austrian-German engineer and businessman (d. 2019)
 * 1938 – Ben Barnes, American businessman and politician, 36th Lieutenant Governor of Texas
 * 1938 – Doug Lewis, Canadian lawyer and politician, 41st Canadian Minister of Justice
 * 1938 – Ronald H. Miller, American theologian, author, and academic (d. 2011)
 * 1938 – Kerry Wendell Thornley, American theorist and author (d. 1988)
 * 1939 – Robert Miller, American art dealer (d. 2011)
 * 1940 – Eric Dancer, English businessman and politician, Lord Lieutenant of Devon
 * 1940 – Billy Fury, English singer-songwriter (d. 1983)
 * 1940 – John McCririck, English journalist (d. 2019)
 * 1940 – Chuck Menville, American animator and screenwriter (d. 1992)
 * 1940 – Anja Silja, German soprano and actress
 * 1940 – Agostino Vallini, Italian cardinal and vicar general of Rome
 * 1941 – Lagle Parek, Estonian architect and politician, Estonian Minister of the Interior
 * 1942 – Buster Williams, American jazz bassist
 * 1942 – Dnyaneshwar Agashe, Indian businessman and cricketer (d. 2009)
 * 1943 – Richard Allen Epstein, American lawyer, author, and academic
 * 1946 – Clare Francis, English sailor and author
 * 1947 – Nigel Emslie, Lord Emslie, Scottish lawyer and judge
 * 1947 – Richard Field, English lawyer and judge
 * 1947 – Sherrie Levine, American photographer
 * 1947 – Tsutomu Wakamatsu, Japanese baseball player, coach, and manager
 * 1948 – Jan Hammer, Czech pianist, composer, and producer
 * 1948 – Alice Harden, American educator and politician (d. 2012)
 * 1948 – Pekka Vasala, Finnish runner
 * 1951 – Olivia Hussey, Argentinian-English actress
 * 1951 – Börje Salming, Swedish ice hockey player and businessman (d. 2022)
 * 1952 – Joe Alaskey, American voice actor (d. 2016)
 * 1952 – Pierre Guité, Canadian ice hockey player
 * 1952 – John McColl, English general and politician, Lieutenant Governor of Jersey
 * 1952 – Željko Ražnatović, Serbian commander "Arkan" (d. 2000)
 * 1952 – John Robertson, Scottish businessman and politician
 * 1954 – Riccardo Patrese, Italian race car driver
 * 1954 – Roddy Piper, Canadian professional wrestler and actor (d. 2015)
 * 1954 – Michael Sembello, American singer-songwriter and guitarist
 * 1955 – Todd Lickliter, American basketball player and coach
 * 1955 – Pete Shelley, English singer-songwriter and guitarist (d. 2018)
 * 1955 – Mike Stroud, English physician and explorer
 * 1956 – Colin Tyre, Lord Tyre, Scottish lawyer and judge
 * 1957 – Teri Austin, Canadian actress
 * 1957 – Afrika Bambaataa, American disc jockey
 * 1957 – Dwane Casey, American basketball coach
 * 1957 – Nick Hornby, English novelist, essayist, lyricist, and screenwriter
 * 1957 – Julia Macur, English lawyer and judge
 * 1957 – Frank McDonough, British historian
 * 1958 – Laslo Babits, Canadian javelin thrower (d. 2013)
 * 1959 – Sean Bean, English actor
 * 1959 – Jimmy Mann, Canadian ice hockey player
 * 1959 – Li Meisu, Chinese shot putter
 * 1960 – Vladimir Polyakov, Russian pole vaulter
 * 1961 – Norman Cowans, Jamaican-English cricketer
 * 1961 – Boomer Esiason, American football player and sportscaster
 * 1961 – Bella Freud, English fashion designer
 * 1962 – Paul Nicholls, English jockey and trainer
 * 1964 – Ken Daneyko, Canadian ice hockey player and sportscaster
 * 1964 – Maynard James Keenan, American singer-songwriter and producer
 * 1964 – Rachel Notley, Canadian politician
 * 1964 – Lela Rochon, American actress
 * 1966 – Vikram, Indian actor and singer
 * 1967 – Henry Ian Cusick, Peruvian-Scottish actor
 * 1967 – Kimberly Elise, American actress
 * 1967 – Marquis Grissom, American baseball player and coach
 * 1967 – Ian Jones, New Zealand rugby player
 * 1967 – Barnaby Joyce, Australian politician, 17th Deputy Prime Minister of Australia
 * 1967 – Liz Phair, American singer-songwriter and guitarist
 * 1968 – Julie Fagerholt, Danish fashion designer
 * 1968 – Phil Henderson, American basketball player and coach (d. 2013)
 * 1968 – Eric Lamaze, Canadian jockey
 * 1968 – Roger Twose, New Zealand cricketer
 * 1968 – Richie Woodhall, English boxer and trainer
 * 1970 – Redman, American rapper, producer, and actor
 * 1971 – Claire Sweeney, English actress
 * 1972 – Gary Bennett, American baseball player
 * 1972 – Tony Boselli, American football player and sportscaster
 * 1972 – Jennifer Garner, American actress
 * 1972 – Muttiah Muralitharan, Sri Lankan cricketer
 * 1972 – Yuichi Nishimura, Japanese footballer and referee
 * 1972 – Terran Sandwith, Canadian ice hockey player
 * 1973 – Katrin Koov, Estonian architect
 * 1973 – Brett Maher, Australian basketball player and sportscaster
 * 1973 – Theo Ratliff, American basketball player
 * 1974 – Mikael Åkerfeldt, Swedish singer-songwriter, guitarist, and producer
 * 1974 – Victoria Beckham, English singer and fashion designer
 * 1975 – Heidi Alexander, English politician
 * 1975 – Travis Roy, American ice hockey player (d. 2020)
 * 1976 – Maurice Wignall, Jamaican hurdler and long jumper
 * 1977 – Chad Hedrick, American speed skater
 * 1977 – Frederik Magle, Danish composer, organist, and pianist
 * 1978 – Monika Bergmann-Schmuderer, German skier
 * 1978 – Lindsay Hartley, American actress
 * 1978 – Jason White, Scottish rugby player
 * 1979 – Eric Brewer, Canadian ice hockey player
 * 1979 – Marija Šestak, Serbian-Slovenian triple jumper
 * 1980 – Fabián Vargas, Colombian footballer
 * 1980 – Curtis Woodhouse, English footballer, boxer, and manager
 * 1981 – Jenny Meadows, English runner
 * 1981 – Hanna Pakarinen, Finnish singer-songwriter
 * 1981 – Ryan Raburn, American baseball player
 * 1981 – Chris Thompson, English runner
 * 1981 – Zhang Yaokun, Chinese footballer
 * 1982 – Brad Boyes, Canadian ice hockey player
 * 1982 – Chuck Kobasew, Canadian ice hockey player
 * 1982 – Tyron Woodley, American mixed martial artist
 * 1983 – Stanislav Chistov, Russian ice hockey player
 * 1983 – Roberto Jiménez, Peruvian footballer
 * 1983 – Andrea Marcato, Italian rugby player
 * 1984 – Pablo Sebastián Álvarez, Argentinian footballer
 * 1984 – Jed Lowrie, American baseball player
 * 1984 – Raffaele Palladino, Italian footballer
 * 1985 – Rooney Mara, American actress
 * 1985 – Luke Mitchell, Australian actor and model
 * 1985 – Jo-Wilfried Tsonga, French tennis player
 * 1986 – Romain Grosjean, French race car driver
 * 1988 – Takahiro Moriuchi, Japanese singer-songwriter
 * 1989 – Paraskevi Papachristou, Greek triple jumper
 * 1989 – Avi Kaplan, singer and songwriter
 * 1990 – Jonathan Brown, Welsh footballer
 * 1992 – Lachlan Maranta, Australian rugby league footballer
 * 1992 – Jo Jinho, South Korean singer
 * 1994 – Alanna Goldie, Canadian fencer
 * 1994 – Yang Hongseok, South Korean singer and actor
 * 1995 – Jung Wheein, South Korean singer
 * 1996 – Lorna Fitzgerald, British actress
 * 1996 – Caitlin Parker, Australian boxer
 * 1996 – Helene Spilling, Norwegian dancer
 * 1998 – Suppapong Udomkaewkanjana (Saint), Thai actor and singer
 * 2001 – Shin Ryujin, South Korean rapper, singer and dancer

Pre-1600

 * 485 – Proclus, Greek mathematician and philosopher (b. 412)
 * 617 – Donnán of Eigg, Irish priest and saint
 * 648 – Xiao, empress of the Sui dynasty
 * 744 – Al-Walid II, Umayyad caliph (b. 706)
 * 818 – Bernard of Italy, Frankish king (b. 797)
 * 858 – Benedict III, pope of the Catholic Church
 * 1071 – Manuel Komnenos, Byzantine military commander (b. c. 1045)
 * 1080 – Harald III of Denmark (b. 1041)
 * 1111 – Robert of Molesme, Christian saint and abbot (b. 1027)
 * 1298 – Árni Þorláksson, Icelandic bishop (b. 1237)
 * 1321 – Infanta Branca of Portugal, daughter of King Afonso III of Portugal (b. 1259)
 * 1331 – Robert de Vere, 6th Earl of Oxford, English nobleman (b. 1257)
 * 1344 – Constantine II, King of Armenia
 * 1355 – Marin Falier, Doge of Venice (b. 1285)
 * 1427 – John IV, Duke of Brabant (b. 1403)
 * 1539 – George, Duke of Saxony (b. 1471)
 * 1574 – Joachim Camerarius, German scholar and translator (b. 1500)

1601–1900

 * 1669 – Antonio Bertali, Italian violinist and composer (b. 1605)
 * 1680 – Kateri Tekakwitha, Mohawk-born Native American saint (b. 1656)
 * 1695 – Juana Inés de la Cruz, Mexican poet and scholar (b. 1651)
 * 1696 – Marie de Rabutin-Chantal, marquise de Sévigné, French author (b. 1626)
 * 1711 – Joseph I, Holy Roman Emperor (b. 1678)
 * 1713 – David Hollatz, Polish pastor and theologian (b. 1648)
 * 1764 – Johann Mattheson, German lexicographer and composer (b. 1681)
 * 1790 – Benjamin Franklin, American inventor, publisher, and politician, 6th President of Pennsylvania (b. 1706)
 * 1799 – Richard Jupp, English surveyor and architect (b. 1728)
 * 1840 – Hannah Webster Foster, American journalist and author (b. 1758)
 * 1843 – Samuel Morey, American engineer (b. 1762)
 * 1882 – George Jennings, English engineer and plumber, invented the flush toilet (b. 1810)
 * 1888 – E. G. Squier, American archaeologist and journalist (b. 1821)
 * 1892 – Alexander Mackenzie, Scottish-Canadian politician, 2nd Prime Minister of Canada (b. 1822)

1901–present

 * 1919 – Svetozar Ćorović, Serbian novelist (b. 1875)
 * 1921 – Manwel Dimech, Maltese journalist, author, and philosopher (b. 1860)
 * 1923 – Laurence Ginnell, Irish lawyer and politician (b. 1852)
 * 1930 – Alexander Golovin, Russian painter and stage designer (b. 1863)
 * 1933 – Kote Marjanishvili, Georgian director and playwright (b. 1872)
 * 1936 – Charles Ruijs de Beerenbrouck, Dutch lawyer and politician, 28th Prime Minister of the Netherlands (b. 1873)
 * 1942 – Jean Baptiste Perrin, French-American physicist and chemist, Nobel Prize laureate (b. 1870)
 * 1944 – J. T. Hearne, English cricketer and coach (b. 1867)
 * 1944 – Dimitrios Psarros, Greek lieutenant, founded the National and Social Liberation (b. 1893)
 * 1946 – Juan Bautista Sacasa, Nicaraguan medical doctor, politician and 20th President of Nicaragua (b. 1874)
 * 1948 – Kantarō Suzuki, Japanese admiral and politician, 42nd Prime Minister of Japan (b. 1868)
 * 1954 – Lucrețiu Pătrășcanu, Romanian lawyer and politician, Romanian Minister of Justice (b. 1900)
 * 1960 – Eddie Cochran, American singer-songwriter and guitarist (b. 1938)
 * 1961 – Elda Anderson, American physicist and health researcher (b. 1899)
 * 1967 – Red Allen, American singer and trumpet player (b. 1908)
 * 1975 – Sarvepalli Radhakrishnan, Indian philosopher and politician, 2nd President of India (b. 1888)
 * 1976 – Henrik Dam, Danish biochemist and physiologist, Nobel Prize laureate (b. 1895)
 * 1977 – William Conway, Irish cardinal (b. 1913)
 * 1983 – Felix Pappalardi, American singer-songwriter, bass player, and producer (b. 1939)
 * 1984 – Claude Provost, Canadian-American ice hockey player (b. 1933)
 * 1986 – Marcel Dassault, French businessman, founded Dassault Aviation (b. 1892)
 * 1987 – Cecil Harmsworth King, English publisher (b. 1901)
 * 1987 – Dick Shawn, American actor (b. 1923)
 * 1988 – Louise Nevelson, Ukrainian-American sculptor and educator (b. 1900)
 * 1990 – Ralph Abernathy, American minister and activist (b. 1936)
 * 1993 – Turgut Özal, Turkish engineer and politician, 8th president of Turkey (b. 1927)
 * 1993 – Gamal Hamdan, Egyptian scholar and geographer (b. 1928)
 * 1994 – Roger Wolcott Sperry, American psychologist and biologist, Nobel Prize laureate (b. 1913)
 * 1995 – Frank E. Resnik, American sergeant and businessman (b. 1928)
 * 1996 – Piet Hein, Danish poet and mathematician (b. 1905)
 * 1997 – Chaim Herzog, Israeli general, lawyer, and politician, 6th President of Israel (b. 1918)
 * 1998 – Linda McCartney, American photographer, activist, and musician (b. 1941)
 * 2003 – Robert Atkins, American physician and cardiologist, created the Atkins diet (b. 1930)
 * 2003 – H. B. Bailey, American race car driver (b. 1936)
 * 2003 – John Paul Getty, Jr., American-English philanthropist (b. 1932)
 * 2003 – Earl King, American blues singer, guitarist and songwriter (b. 1934)
 * 2003 – Yiannis Latsis, Greek businessman (b. 1910)
 * 2004 – Edmond Pidoux, Swiss author and poet (b. 1908)
 * 2006 – Jean Bernard, French physician and haematologist (b. 1907)
 * 2006 – Scott Brazil, American director and producer (b. 1955)
 * 2006 – Henderson Forsythe, American actor (b. 1917)
 * 2007 – Kitty Carlisle, American actress, singer, socialite and game show panelist (b. 1910)
 * 2008 – Aimé Césaire, Caribbean-French poet and politician (b. 1913)
 * 2008 – Danny Federici, American organist and accordion player (b. 1950)
 * 2011 – Eric Gross, Austrian-Australian pianist and composer (b. 1926)
 * 2011 – Michael Sarrazin, Canadian actor (b. 1940)
 * 2011 – Robert Vickrey, American artist and author (b. 1926)
 * 2012 – Leila Berg, English journalist and author (b. 1917)
 * 2012 – J. Quinn Brisben, American educator and politician (b. 1934)
 * 2012 – Dimitris Mitropanos, Greek singer (b. 1948)
 * 2012 – Nityananda Mohapatra, Indian journalist, poet, and politician (b. 1912)
 * 2012 – Jonathan V. Plaut, American rabbi and author (b. 1942)
 * 2012 – Stanley Rogers Resor, American soldier, lawyer, and politician, 9th United States Secretary of the Army (b. 1917)
 * 2013 – Carlos Graça, São Toméan politician, Prime Minister of São Tomé and Príncipe (b. 1931)
 * 2013 – Bi Kidude, Tanzanian Taarab singer (b. ≈1910)
 * 2013 – Yngve Moe, Norwegian bass player and songwriter (b. 1957)
 * 2013 – V. S. Ramadevi, Indian politician, 13th Governor of Karnataka (b. 1934)
 * 2014 – Gabriel García Márquez, Colombian journalist and author, Nobel Prize laureate (b. 1927)
 * 2014 – Bernat Klein, Serbian-Scottish fashion designer and painter (b. 1922)
 * 2014 – Wojciech Leśnikowski, Polish–American architect and academic (b. 1938)
 * 2014 – Karpal Singh, Malaysian lawyer and politician (b. 1940)
 * 2015 – Robert P. Griffin, American soldier, lawyer, and politician (b. 1923)
 * 2015 – Scotty Probasco, American businessman and philanthropist (b. 1928)
 * 2015 – Jeremiah J. Rodell, American general (b. 1921)
 * 2015 – A. Alfred Taubman, American businessman and philanthropist (b. 1924)
 * 2016 – Chyna, American wrestler (b. 1969)
 * 2016 – Doris Roberts, American actress (b. 1925)
 * 2018 – Barbara Bush, American political matriarch and literacy advocate, First Lady of the United States (1989–1993), and Second Lady of the United States (1981–1989) (b. 1925)
 * 2018 – Carl Kasell, American radio personality (b. 1934)
 * 2019 – Alan García, Peruvian lawyer and politician, 61st and 64th President of Peru (b. 1949)
 * 2022 – Radu Lupu, Romanian pianist (b. 1945)

Holidays and observances

 * Christian feast day:
 * Donnán of Eigg
 * Henry Heath
 * Kateri Tekakwitha (Canada)
 * Robert of Molesme
 * Shemon bar Sabbae
 * April 17 (Eastern Orthodox liturgics)
 * Evacuation Day (Syria), celebrates the recognition of the independence of Syria from France in 1946.
 * FAO Day (Iraq)
 * Flag Day (American Samoa)
 * Malbec World Day
 * Women's Day (Gabon)
 * World Hemophilia Day

title: April 17


text:
Alan Ayckbourn

Sir Alan Ayckbourn (born 12 April 1939) is a prolific British playwright and director. He has written and produced as of 2024, 90 full-length plays in Scarborough and London and was, between 1972 and 2009, the artistic director of the Stephen Joseph Theatre in Scarborough, where all but four of his plays have received their first performance. More than 40 have subsequently been produced in the West End, at the Royal National Theatre or by the Royal Shakespeare Company since his first hit Relatively Speaking opened at the Duke of York's Theatre in 1967.

Major successes include Absurd Person Singular (1975), The Norman Conquests trilogy (1973), Bedroom Farce (1975), Just Between Ourselves (1976), A Chorus of Disapproval (1984), Woman in Mind (1985), A Small Family Business (1987), Man of the Moment (1988), House & Garden (1999) and Private Fears in Public Places (2004). His plays have won numerous awards, including seven London Evening Standard Awards. They have been translated into over 35 languages and are performed on stage and television throughout the world. Ten of his plays have been staged on Broadway, attracting two Tony nominations, and one Tony award.

Childhood
Ayckbourn was born in Hampstead, London. His mother, Irene Worley ("Lolly") (1906–1998), was a writer of short stories who published under the name "Mary James". His father, Horace Ayckbourn (1904–1965), was an orchestral violinist and was the lead violinist at the London Symphony Orchestra. His parents, who separated shortly after World War II, never married, and Ayckbourn's mother divorced her first husband to marry again in 1948.

Ayckbourn wrote his first play at Wisborough Lodge (a preparatory school in the village of Wisborough Green) when he was about 10. While he was at prep school as a boarder, his mother wrote to tell him she was marrying Cecil Pye, a bank manager. His new family consisted of his mother, his stepfather and Christopher, his stepfather's son by an earlier marriage. This relationship too, reportedly ran into difficulties early on.

Ayckbourn attended Haileybury and Imperial Service College, in the village of Hertford Heath and, while there, he toured Europe and America with the school's Shakespeare company.

Adult life
After leaving school at 17, Ayckbourn took several temporary jobs in various places before starting a temporary position at the Scarborough Library Theatre, where he was introduced to the artistic director, Stephen Joseph. It is said that Joseph became both a mentor and father figure for Ayckbourn until his untimely death in 1967, and Ayckbourn has consistently spoken highly of him.

Ayckbourn's career was briefly interrupted when he was called up for National Service. He was swiftly discharged, officially on medical grounds, but it is suggested that a doctor who noticed his reluctance to join the Armed Forces deliberately failed the medical as a favour. Although Ayckbourn continued to move wherever his career took him, he settled in Scarborough, eventually buying Longwestgate House, which had previously been owned by his mentor, Joseph.

In 1957, Ayckbourn married Christine Roland, another member of the Library Theatre company. Ayckbourn's first two plays were, in fact, written jointly with her under the pseudonym of "Roland Allen". They had two sons, Steven and Philip. However, the marriage had difficulties, which eventually led to their separation in 1971. Ayckbourn said that his relationship with Roland became easy once they agreed their marriage was over. About this time, he shared a home with Heather Stoney, an actress he had first met ten years earlier. Like his mother, neither he nor Roland sought an immediate divorce and it was not until thirty years later, in 1997, that they were formally divorced and Ayckbourn married Stoney. One side effect of the timing is that, when Ayckbourn was awarded a knighthood a few months before the divorce, both his first and second wives were entitled to take the title of Lady Ayckbourn.

In February 2006, he suffered a stroke in Scarborough, and stated: "I hope to be back on my feet, or should I say my left leg, as soon as possible, but I know it is going to take some time. In the meantime I am in excellent hands and so is the Stephen Joseph Theatre." He left hospital after eight weeks and returned to directing after six months. The following year, Ayckbourn announced he would step down as artistic director of the Stephen Joseph Theatre. He continues, however, to write and direct his own work at the theatre.

Influence on plays
Since the time Ayckbourn's plays became established in the West End, interviewers have raised the question of whether his work is autobiographical. There is no clear answer to this question. There has been only one biography, written by Paul Allen, which primarily covers his career in the theatre. Ayckbourn has frequently said he sees aspects of himself in all of his characters. In Bedroom Farce (1975), for example, he admitted to being, in some respects, all four of the men in the play. It has been suggested that, after Ayckbourn himself, the person who is used most often in his plays is his mother, particularly as Susan in Woman in Mind (1985).

What is less clear is the extent to which events in Ayckbourn's life have influenced his writing. It is true that the theme of marriages in difficulty was heavily present throughout his plays in the early seventies, at about the time his own marriage was coming to an end. However, by that time, he had also witnessed the failure of his parents' relationships and those of some of his friends. Which relationships, if any, he drew on for his plays, is unclear. In Paul Allen's biography, Ayckbourn is briefly compared with Dafydd and Guy in A Chorus of Disapproval (1984). Both characters feel themselves to be in trouble and there was speculation that Ayckbourn himself might have felt the same way. At the time, he had reportedly become seriously involved with another actress, which threatened his relationship with Stoney. It is unclear whether this had any effect on the writing; Paul Allen's view is that Ayckbourn did not use his personal experiences to write his plays.

It is possible that Ayckbourn wrote plays with himself and his own situation in mind but, as Ayckbourn is portrayed as a guarded and private man, it is hard to imagine him exposing his own life in his plays to any great degree. In the biography, Paul Allen writes, with regard to a suggestion in Cosmopolitan that Ayckbourn's plays were becoming autobiographical: "If we take that to mean that his plays tell his own life story, he still hasn't started."

Early career and acting
On leaving school, Ayckbourn's theatrical career began immediately, when his French master introduced him to Sir Donald Wolfit. Ayckbourn joined Wolfit on tour to the Edinburgh Festival Fringe as an acting assistant stage manager (a role that involved both acting and stage management) for three weeks. His first experiences on the professional stage were various roles in The Strong are Lonely by Fritz Hochwälder. In the following year, Ayckbourn appeared in six other plays at the Connaught Theatre, Worthing and the Thorndike theatre, Leatherhead.

In 1957, Ayckbourn was employed by the director Stephen Joseph at the Library Theatre, Scarborough, the predecessor to the modern Stephen Joseph Theatre. Again, his role was initially as acting stage manager. This employment led to Ayckbourn's first professional script commission, in 1958. When he complained about the quality of a script he was performing, Joseph challenged him to write a better one. The result was The Square Cat, written under the pseudonym Roland Allen and first performed in 1959. In this play, Ayckbourn himself played the character of Jerry Watiss.

In 1962, after thirty-four appearances in plays at the Library Theatre, including four of his own, Ayckbourn moved to Stoke-on-Trent to help set up the Victoria Theatre (now the New Vic), where he appeared in a further eighteen plays. His final appearance in one of his own plays was as the Crimson Gollywog in the disastrous children's play Christmas v Mastermind. He left the Stoke company in 1964, officially to commit his time to the London production of Mr. Whatnot, but reportedly because was having trouble working with the artistic director, Peter Cheeseman. By now, his career as a writer was coming to fruition and his acting career was sidelined.

His final role on stage was as Jerry in Two for the Seesaw by William Gibson, at the Civic Theatre in Rotherham. He was left stranded on stage because Heather Stoney (his future wife) was unable to re-appear due to her props not being ready for use. This led to his conclusion that acting was more trouble than it was worth. The assistant stage manager on the production, Bill Kenwright, would go on to become one of the UK's most successful producers.

Writing
Ayckbourn's first play, The Square Cat, was sufficiently popular locally to secure further commissions, although neither this nor the following three plays had much impact beyond Scarborough. After his transfer to Victoria Theatre in Stoke-on-Trent, Christmas v Mastermind, flopped; this play is now universally regarded as Ayckbourn's greatest disaster.

Ayckbourn's fortunes revived in 1963 with Mr. Whatnot, which also premiered at the Victoria Theatre. This was the first play that Ayckbourn was sufficiently happy with to allow continued performances today, and the first play to receive a West End performance. However, the West End production flopped, in part due to misguided casting. After this, Ayckbourn experimented by collaborating with comedians, first writing a monologue for Tommy Cooper, and later with Ronnie Barker, who played Lord Slingsby-Craddock in the London production of Mr Whatnot in 1964, on the scripts for LWT's Hark at Barker. Ayckbourn used the pseudonym Peter Caulfield because he was under exclusive contract to the BBC at the time.

In 1965, back at the Scarborough Library Theatre, Meet my Father was produced, and later retitled Relatively Speaking. This time, the play was a massive success, both in Scarborough and in the West End, earning Ayckbourn a congratulatory telegram from Noël Coward. This was not quite the end of Ayckbourn's hit-and-miss record. His next play, The Sparrow ran for only three weeks at Scarborough but the following play, How the Other Half Loves, secured his runaway success as a playwright.

The height of Ayckbourn's commercial success came with plays such as Absurd Person Singular (1975), The Norman Conquests trilogy (1973), Bedroom Farce (1975) and Just Between Ourselves (1976). These plays focused heavily on marriage in the British middle classes. The only failure during this period was a 1975 musical with Andrew Lloyd Webber, Jeeves; even this did little to dent Ayckbourn's career.

From the 1980s, Ayckbourn moved away from the recurring theme of marriage to explore other contemporary issues. One example was Woman in Mind, a play performed entirely from the perspective of a woman going through a nervous breakdown. He also experimented with unconventional ways of writing plays: Intimate Exchanges, for example, has one beginning and sixteen possible endings, and in House & Garden, two plays take place simultaneously on two separate stages. He also diversified into children's theatre, such as Mr A's Amazing Maze Plays and musical plays, such as By Jeeves (a more successful rewrite of the original Jeeves).

With a résumé of over seventy plays, of which more than forty have played at the National Theatre or in the West End, Alan Ayckbourn is one of England's most successful living playwrights. Despite his success, honours and awards (which include a prestigious Laurence Olivier Award), Alan Ayckbourn remains a relatively anonymous figure, dedicated to regional theatre. Throughout his writing career, all but four of his plays premiered at the Stephen Joseph Theatre in Scarborough in its three different locations.

Ayckbourn received the CBE in 1987 and was knighted in the 1997 New Year Honours. It is frequently claimed (but not proved) that Alan Ayckbourn is the most performed living English playwright, and the second most performed of all time, after Shakespeare.

Although Ayckbourn's plays no longer dominate the theatrical scene on the scale of his earlier works, he continues to write. Among major success has been Private Fears in Public Places, which had a hugely successful Off-Broadway run at 59E59 Theaters and, in 2006, was made into a film, Cœurs, directed by Alain Resnais. After Ayckbourn suffered a stroke, there was uncertainty as to whether he could continue to write. The play that premiered immediately after his stroke, If I Were You, had been written before his illness; the first play written afterwards, Life and Beth, premiered in the summer of 2008. Ayckbourn continues to write for the Stephen Joseph Theatre on the invitation of his successor as artistic director, Chris Monks. The first new play under this arrangement, My Wonderful Day, was performed in October 2009.

Ayckbourn continues to experiment with theatrical form. The play Roundelay opened in September 2014; before each performance, members of the audience are invited to extract five coloured ping pong balls from a bag, leaving the order in which each of the five acts is played left to chance, and allowing 120 possible permutations. In Arrivals and Departures (2013), the first half of the play is told from the point of view of one character, only for the second half to dramatise the same events from the point of view of another.

Many of Ayckbourn's plays, including Private Fears in Public Places, Intimate Exchanges, My Wonderful Day and Neighbourhood Watch, have had their New York premiere at 59E59 Theaters as part of the annual Brits Off Broadway Festival.

In 2019, Ayckbourn had published his first novel, The Divide, which had previously been showcased during a reading at the Stephen Joseph Theatre.

As a consequence of the Covid lockdown, Ayckbourn's 2020 play, Anno Domino, was recorded as a radio production, with Ayckbourn and his wife Heather playing all the roles. Similarly, Ayckbourn's Covid-period 2021 play, The Girl Next Door, was streamed online and made available behind a paywall on the Stephen Joseph Theatre's website.

In 2022, the first Ayckbourn play in around 60 years premiered in a venue other than Scarborough: All Lies at the Old Laundry in Bowness-on-Windermere.

Directing
Although Ayckbourn is best known as a writer, it is said that he only spends 10% of his time writing plays. Most of the remaining time is spent directing.

Ayckbourn began directing at the Scarborough Library Theatre in 1961, with a production of Gaslight by Patrick Hamilton. During that year and the next, he directed five other plays in Scarborough and, after transferring to the Victoria Theatre, in 1963 directed a further six plays. Between 1964 and 1967, much of his time was taken up by various productions of his early successes, Mr. Whatnot and Relatively Speaking and he directed only one play, The Sparrow, which he wrote and which was later withdrawn. In 1968, he resumed directing plays regularly, mostly at Scarborough. At this time he also worked as a radio drama producer for the BBC, based in Leeds.

At first, his directing career was kept separate from his writing career. It was not until 1963 that Ayckbourn directed a play of his own (a revival of Standing Room Only) and 1967 before he directed a premiere of his own (The Sparrow). The London premieres remained in the hands of other directors for longer; the first of his own plays to be directed by him in London was Bedroom Farce, in 1977.

After the death of Stephen Joseph in 1967, the Director of Productions was appointed on an annual basis. Ayckbourn was offered the position in 1969 and 1970, succeeding Rodney Wood, but he handed the position over to Caroline Smith in 1971, having spent most that year in the US with How the Other Half Loves. He became Director of Productions again in 1972 and, on 12 November of that year, he was made the permanent artistic director of the theatre.

In mid-1986, Ayckbourn accepted an invitation to work as a visiting director for two years at the National Theatre in London, to form his own company, and perform a play in each of the three auditoria, provided at least one was a new play of his own. He used a stock company that included performers such as Michael Gambon, Polly Adams and Simon Cadell. The three plays became four: Tons of Money by Will Evans and Valentine, with adaptations by Ayckbourn (Lyttelton); Arthur Miller's A View From the Bridge (Cottesloe); his own play A Small Family Business (Olivier) and John Ford's 'Tis Pity She's a Whore (Olivier again). During this time, Ayckbourn shared his role of artistic director of the Stephen Joseph Theatre with Robin Herford and returned in 1987 to direct the premiere of Henceforward....

He announced in 1999 that he would step back from directing the work of other playwrights, to concentrate on his own plays, the last one being Rob Shearman's Knights in Plastic Armour in 1999; he made one exception in 2002, when he directed the world premiere of Tim Firth's The Safari Party.

In 2002, following a dispute over the Duchess Theatre's handling of Damsels in Distress, Ayckbourn sharply criticised both this and the West End's treatment of theatre in general and, in particular, their casting of celebrities. Although he did not explicitly say he would boycott the West End, he did not return to direct in there again until 2009, with a revival of Woman in Mind. He did, however, allow other West End producers to revive Absurd Person Singular in 2007 and The Norman Conquests in 2008.

Ayckbourn suffered a stroke in February 2006 and returned to work in September; the premiere of his 70th play If I Were You at the Stephen Joseph Theatre came the following month.

He announced in June 2007 that he would retire as artistic director of the Stephen Joseph Theatre after the 2008 season. His successor, Chris Monks, took over at the start of the 2009–2010 season but Ayckbourn remained to direct premieres and revivals of his work at the theatre, beginning with How the Other Half Loves in June 2009.

In March 2010, he directed an in-the-round revival of his play Taking Steps at the Orange Tree Theatre, winning universal press acclaim.

In July 2014, Ayckbourn directed a musical adaptation of The Boy Who Fell into A Book, with musical adaptation and lyrics by Paul James and music by Eric Angus and Cathy Shostak. The show ran in The Stephen Joseph Theatre and received critical acclaim.

Honours and awards

 * 1973: Evening Standard Award, Best Comedy, for Absurd Person Singular
 * 1974: Evening Standard Award, Best Play, for The Norman Conquests
 * 1977: Evening Standard Award, Best Play, for Just Between Ourselves
 * 1981: Honorary Doctor of Letters degree (Litt.D.) from University of Hull
 * 1985: Evening Standard Award, Best Comedy, for A Chorus of Disapproval
 * 1985: Laurence Olivier Award, Best Comedy, for A Chorus of Disapproval
 * 1986: Freedom of the Borough of Scarborough.
 * 1987: Evening Standard Award, Best Play, for A Small Family Business
 * 1987: Plays and Players Award
 * 1987: Honorary Doctor of Letters degree (Litt.D.) from Keele University
 * 1987: Honorary Doctor of Letters degree (Litt.D.) from University of Leeds
 * 1987: Commander of the Order of the British Empire (CBE)
 * 1989: Evening Standard Award, Best Comedy, for Henceforward...
 * 1990: Evening Standard Award, Best Comedy, for Man of the Moment
 * 1997: Knight Bachelor
 * 1998: Honorary Doctor of the University degree (D.Univ.) from Open University
 * 2008: Induction into the American Theater Hall of Fame
 * 2009: Laurence Olivier Special Award
 * 2009: The Critics' Circle annual award for Distinguished Service to the Arts
 * 2011: Honorary Doctor of Letters degree (Litt.D.) from York St. John University

Ayckbourn also sits on the Council of the Society of Authors. He is also a longtime patron of Next Stage Theatre Company, an amateur theatre company based in Bath.

One-act plays
Alan Ayckbourn has written eight one-act plays. Five of them (Mother Figure, Drinking Companion, Between Mouthfuls, Gosforth's Fete and Widows Might) were written for Confusions, first performed in 1974.

The other three one-act plays are:
 * Countdown, first performed in 1962, most well known as part of Mixed Doubles, a set of short one-act plays and monologues contributed by nine different authors.
 * Ernie's Incredible Illucinations, written in 1969 for a collection of short plays and intended for performance by schools.
 * A Cut in the Rates, performed at the Stephen Joseph Theatre in 1984, and filmed for a BBC documentary.

Books

 * Ayckbourn, Alan (2019) The Divide. UK: PS Publishing. ISBN 978-1-786364-47-0.
 * Ayckbourn, Alan (2019) The Divide. UK: PS Publishing. ISBN 978-1-786364-47-0.
 * Ayckbourn, Alan (2019) The Divide. UK: PS Publishing. ISBN 978-1-786364-47-0.

Film adaptations of Ayckbourn plays
Plays adapted as films include:

 * A Chorus of Disapproval (play) filmed as A Chorus of Disapproval (1988 film), directed by Michael Winner;
 * Intimate Exchanges (play) filmed as Smoking/No Smoking (1993 film), directed by Alain Resnais;
 * The Revengers' Comedies (play) filmed as The Revengers' Comedies (also known as Sweet Revenge), directed by Malcolm Mowbray;
 * Private Fears in Public Places (play) filmed as Cœurs (2006 film) directed by Alain Resnais.
 * Life of Riley (play) filmed as Life of Riley (2014 film) directed by Alain Resnais.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Alan Ayckbourn


text:
Alpha Centauri

Alpha Centauri (α Centauri, α Cen, or Alpha Cen) is a triple star system in the southern constellation of Centaurus. It consists of three stars: Rigil Kentaurus (α Centauri A), Toliman (α Centauri B), and Proxima Centauri (α Centauri C). Proxima Centauri is the closest star to the Sun at 4.2465 light-years (1.3020 pc).

α Centauri A and B are Sun-like stars (class G and K, respectively) that together form the binary star system α Centauri AB. To the naked eye, these two main components appear to be a single star with an apparent magnitude of −0.27. It is the brightest star in the constellation and the third-brightest in the night sky, outshone by only Sirius and Canopus.

α Centauri A has 1.1 times the mass and 1.5 times the luminosity of the Sun, while α Centauri B is smaller and cooler, at 0.9 solar mass and less than 0.5 solar luminosity. The pair orbit around a common centre with an orbital period of 79 years. Their elliptical orbit is eccentric, so that the distance between A and B varies from 35.6 astronomical units, or about the distance between Pluto and the Sun, to 11.2 , or about the distance between Saturn and the Sun.

α Centauri C, or Proxima Centauri, is a small faint red dwarf (class M). Though not visible to the naked eye, Proxima Centauri is the closest star to the Sun at a distance of 1.30 pc, slightly closer than α Centauri AB. Currently, the distance between Proxima Centauri and α Centauri AB is about 13000 AU, equivalent to about 430 times the radius of Neptune's orbit.

Proxima Centauri has two confirmed planets: Proxima b, an Earth-sized planet in the habitable zone discovered in 2016, and Proxima d, a candidate sub-Earth which orbits very closely to the star, announced in 2022. The existence of Proxima c, a mini-Neptune 1.5 astronomical unit away discovered in 2019, is controversial. α Centauri A may have a Neptune-sized planet in the habitable zone, though it is not yet known with certainty to be planetary in nature and could be an artifact of the discovery mechanism. α Centauri B has no known planets: Planet α Cen Bb, purportedly discovered in 2012, was later disproven, and no other planet has yet been confirmed.

Etymology and nomenclature
α Centauri (Latinised to Alpha Centauri) is the system's designation given by J. Bayer in 1603. It belongs to the constellation Centaurus, named after the half human, half horse creature in Greek mythology. Hercules accidentally wounded the centaur and placed him in the sky after his death. Alpha Centauri marks the right front hoof of the Centaur. The common name Rigil Kentaurus is a Latinisation of the Arabic translation رجل القنطورس Rijl al-Qinṭūrus, meaning "the Foot of the Centaur". Qinṭūrus is the Arabic transliteration of the Greek $Κένταυρος$ (Kentaurus). The name is frequently abbreviated to Rigil Kent or even Rigil, though the latter name is better known for Rigel ($−21.4$ Orionis).

An alternative name found in European sources, Toliman, is an approximation of the Arabic الظليمان aẓ-Ẓalīmān (in older transcription, aṭ-Ṭhalīmān), meaning 'the (two male) Ostriches', an appellation Zakariya al-Qazwini had applied to the pair of stars Lambda and Mu Sagittarii; it was often not clear on old star maps which name was intended to go with which star (or stars), and the referents changed over time.

A third name that has been used is Bungula. Its origin is not known, but it may have been coined from the Greek letter beta ($−18.6$) and Latin ungula 'hoof', originally for Beta Centauri (the other hoof).

α Centauri C was discovered in 1915 by Robert T. A. Innes, who suggested that it be named Proxima Centaurus,. The name Proxima Centauri later became more widely used and is now listed by the International Astronomical Union (IAU) as the approved proper name; commonly, it is frequently abbreviated to Proxima.

In 2016, the Working Group on Star Names of the IAU, having decided to attribute proper names to individual component stars rather than to multiple systems, approved the name Rigil Kentaurus as being restricted to α Centauri A and the name Proxima Centauri  for α Centauri C. On 10 August 2018, the IAU approved the name Toliman  for α Centauri B.

Observation
To the naked eye, α Centauri AB appears to be a single star, the brightest in the southern constellation of Centaurus. Their apparent angular separation varies over about 80 years between 2 and 22 arcseconds (the naked eye has a resolution of 60 arcsec), but through much of the orbit, both are easily resolved in binoculars or small telescopes. At −0.27 apparent magnitude (combined for A and B magnitudes ), Alpha Centauri is a first-magnitude star and is fainter only than Sirius and Canopus. It is the outer star of The Pointers or The Southern Pointers, so called because the line through Beta Centauri (Hadar/Agena), some 4.5° west, points to the constellation Crux—the Southern Cross. The Pointers easily distinguish the true Southern Cross from the fainter asterism known as the False Cross.

South of about 29° South latitude, α Cen is circumpolar and never sets below the horizon. North of about 29° N latitude, Alpha Centauri never rises. Alpha Centauri lies close to the southern horizon when viewed from the 29° North latitude to the equator (close to Hermosillo and Chihuahua City in Mexico; Galveston, Texas; Ocala, Florida; and Lanzarote, the Canary Islands of Spain), but only for a short time around its culmination. The star culminates each year at local midnight on 24 April and at local 9 p.m. on 8 June.

As seen from Earth, Proxima Centauri is 2.2° southwest from α Centauri AB ; this distance is about four times the angular diameter of the Moon. Proxima Centauri appears as a deep-red star of a typical apparent magnitude of 11.1 in a sparsely populated star field, requiring moderately sized telescopes to be seen. Listed as V645 Cen in the General Catalogue of Variable Stars, version 4.2, this UV Ceti star or "flare star" can unexpectedly brighten rapidly by as much as 0.6 magnitude at visual wavelengths, then fade after only a few minutes. Some amateur and professional astronomers regularly monitor for outbursts using either optical or radio telescopes. In August 2015, the largest recorded flares of the star occurred, with the star becoming 8.3 times brighter than normal on 13 August, in the B band (blue light region).

Alpha Centauri may be inside the G-cloud of the Local Bubble, and its nearest known system is the binary brown dwarf system Luhman 16, at 3.6 ly from Alpha Centauri.

Observational history

Alpha Centauri is listed in the 2nd century the star catalog appended to Ptolemy's Almagest. He gave its ecliptic coordinates, but texts differ as to whether the ecliptic latitude reads 44° 10′ South or 41° 10′ South. (Presently the ecliptic latitude is 43.5° South, but it has decreased by a fraction of a degree since Ptolemy's time due to proper motion.) In Ptolemy's time, Alpha Centauri was visible from Alexandria, Egypt, at 31° N, but, due to precession, its declination is now –60° 51′ South, and it can no longer be seen at that latitude. English explorer Robert Hues brought Alpha Centauri to the attention of European observers in his 1592 work Tractatus de Globis, along with Canopus and Achernar, noting:

"Now, therefore, there are but three Stars of the first magnitude that I could perceive in all those parts which are never seene here in England. The first of these is that bright Star in the sterne of Argo which they call Canobus [Canopus]. The second [Achernar] is in the end of Eridanus. The third [Alpha Centauri] is in the right foote of the Centaure."

The binary nature of Alpha Centauri AB was recognized in December 1689 by Jean Richaud, while observing a passing comet from his station in Puducherry. Alpha Centauri was only the third binary star to be discovered, preceded by Mizar AB and Acrux.

The large proper motion of Alpha Centauri AB was discovered by Manuel John Johnson, observing from Saint Helena, who informed Thomas Henderson at the Royal Observatory, Cape of Good Hope of it. The parallax of Alpha Centauri was subsequently determined by Henderson from many exacting positional observations of the AB system between April 1832 and May 1833. He withheld his results, however, because he suspected they were too large to be true, but eventually published them in 1839 after Bessel released his own accurately determined parallax for 61 Cygni in 1838. For this reason, Alpha Centauri is sometimes considered as the second star to have its distance measured because Henderson's work was not fully acknowledged at first. (The distance of Alpha Centauri from the Earth is now reckoned at 4.396 light-years or 4.396 ly.)

Later, John Herschel made the first micrometrical observations in 1834. Since the early 20th century, measures have been made with photographic plates.

By 1926, William Stephen Finsen calculated the approximate orbit elements close to those now accepted for this system. All future positions are now sufficiently accurate for visual observers to determine the relative places of the stars from a binary star ephemeris. Others, like D. Pourbaix (2002), have regularly refined the precision of new published orbital elements.

Robert T. A. Innes discovered Proxima Centauri in 1915 by blinking photographic plates taken at different times during a proper motion survey. These showed large proper motion and parallax similar in both size and direction to those of α Centauri AB, which suggested that Proxima Centauri is part of the α Centauri system and slightly closer to Earth than α Centauri AB. As such, Innes concluded that Proxima Centauri was the closest star to Earth yet discovered.

Kinematics

All components of α Centauri display significant proper motion against the background sky. Over centuries, this causes their apparent positions to slowly change. Proper motion was unknown to ancient astronomers. Most assumed that the stars were permanently fixed on the celestial sphere, as stated in the works of the philosopher Aristotle. In 1718, Edmond Halley found that some stars had significantly moved from their ancient astrometric positions.

In the 1830s, Thomas Henderson discovered the true distance to α Centauri by analysing his many astrometric mural circle observations. He then realised this system also likely had a high proper motion. In this case, the apparent stellar motion was found using Nicolas Louis de Lacaille's astrometric observations of 1751–1752, by the observed differences between the two measured positions in different epochs.

Calculated proper motion of the centre of mass for α Centauri AB is about 3620 mas/y (milliarcseconds per year) toward the west and 694 mas/y toward the north, giving an overall motion of 3686 mas/y in a direction 11° north of west. The motion of the centre of mass is about 6.1 arcmin each century, or 1.02° each millennium. The speed in the western direction is 23.0 km/s and in the northerly direction 4.4 km/s. Using spectroscopy the mean radial velocity has been determined to be around 22.4 km/s towards the Solar System. This gives a speed with respect to the Sun of 32.4 km/s, very close to the peak in the distribution of speeds of nearby stars.

Since α Centauri AB is almost exactly in the plane of the Milky Way as viewed from Earth, many stars appear behind it. In early May 2028, α Centauri A will pass between the Earth and a distant red star, when there is a 45% probability that an Einstein ring will be observed. Other conjunctions will also occur in the coming decades, allowing accurate measurement of proper motions and possibly giving information on planets.

Predicted future changes

Based on the system's common proper motion and radial velocities, α Centauri will continue to change its position in the sky significantly and will gradually brighten. For example, in about 6,200 CE, α Centauri's true motion will cause an extremely rare first-magnitude stellar conjunction with Beta Centauri, forming a brilliant optical double star in the southern sky. It will then pass just north of the Southern Cross or Crux, before moving northwest and up towards the present celestial equator and away from the galactic plane. By about 26,700 CE, in the present-day constellation of Hydra, α Centauri will reach perihelion at 0.90 pc away, though later calculations suggest that this will occur in 27,000 AD. At its nearest approach, α Centauri will attain a maximum apparent magnitude of −0.86, comparable to present-day magnitude of Canopus, but it will still not surpass that of Sirius, which will brighten incrementally over the next 60,000 years, and will continue to be the brightest star as seen from Earth (other than the Sun) for the next 210,000 years.

Stellar system
Alpha Centauri is a triple star system, with its two main stars, A and B, together comprising a binary component. The AB designation, or older A×B, denotes the mass centre of a main binary system relative to companion star(s) in a multiple star system. AB-C refers to the component of Proxima Centauri in relation to the central binary, being the distance between the centre of mass and the outlying companion. Because the distance between Proxima (C) and either of Alpha Centauri A or B is similar, the AB binary system is sometimes treated as a single gravitational object.

Orbital properties

The A and B components of Alpha Centauri have an orbital period of 79.762 years. Their orbit is moderately eccentric, as it has an eccentricity of almost 0.52; their closest approach or periastron is 11.2 AU, or about the distance between the Sun and Saturn; and their furthest separation or apastron is 35.6 AU, about the distance between the Sun and Pluto. The most recent periastron was in August 1955 and the next will occur in May 2035; the most recent apastron was in May 1995 and will next occur in 2075.

Viewed from Earth, the apparent orbit of A and B means that their separation and position angle (PA) are in continuous change throughout their projected orbit. Observed stellar positions in 2019 are separated by 4.92 arcsec through the PA of 337.1°, increasing to 5.49 arcsec through 345.3° in 2020. The closest recent approach was in February 2016, at 4.0 arcsec through the PA of 300°. The observed maximum separation of these stars is about 22 arcsec, while the minimum distance is 1.7 arcsec. The widest separation occurred during February 1976, and the next will be in January 2056.

Alpha Centauri C is about 13000 AU from Alpha Centauri AB, equivalent to about 5% of the distance between Alpha Centauri AB and the Sun. Until 2017, measurements of its small speed and its trajectory were of too little accuracy and duration in years to determine whether it is bound to Alpha Centauri AB or unrelated.

Radial velocity measurements made in 2017 were precise enough to show that Proxima Centauri and Alpha Centauri AB are gravitationally bound. The orbital period of Proxima Centauri is approximately $79.762$ years, with an eccentricity of 0.5, much more eccentric than Mercury's. Proxima Centauri comes within $17.493$ of AB at periastron, and its apastron occurs at $0.519$.

Physical properties

Asteroseismic studies, chromospheric activity, and stellar rotation (gyrochronology) are all consistent with the Alpha Centauri system being similar in age to, or slightly older than, the Sun. Asteroseismic analyses that incorporate tight observational constraints on the stellar parameters for the Alpha Centauri stars have yielded age estimates of $79.243$ Gyr, $205.073$ Gyr, 5.2 ± 1.9 Gyr, 6.4 Gyr, and $1,875.66$ Gyr. Age estimates for the stars based on chromospheric activity (Calcium H & K emission) yield 4.4 ± 2.1 Gyr, whereas gyrochronology yields $231.519$ Gyr. Stellar evolution theory implies both stars are slightly older than the Sun at 5 to 6 billion years, as derived by their mass and spectral characteristics.

From the orbital elements, the total mass of Alpha Centauri AB is about – or twice that of the Sun. The average individual stellar masses are about and, respectively, though slightly different masses have also been quoted in recent years, such as  and , totalling. Alpha Centauri A and B have absolute magnitudes of +4.38 and +5.71, respectively.

Alpha Centauri A
Alpha Centauri A, also known as Rigil Kentaurus, is the principal member, or primary, of the binary system. It is a solar-like main-sequence star with a similar yellowish colour, whose stellar classification is spectral type G2-V; it is about 10% more massive than the Sun, with a radius about 22% larger. When considered among the individual brightest stars in the night sky, it is the fourth-brightest at an apparent magnitude of +0.01, being slightly fainter than Arcturus at an apparent magnitude of −0.05.

The type of magnetic activity on Alpha Centauri A is comparable to that of the Sun, showing coronal variability due to star spots, as modulated by the rotation of the star. However, since 2005 the activity level has fallen into a deep minimum that might be similar to the Sun's historical Maunder Minimum. Alternatively, it may have a very long stellar activity cycle and is slowly recovering from a minimum phase.

Alpha Centauri B
Alpha Centauri B, also known as Toliman, is the secondary star of the binary system. It is a main-sequence star of spectral type K1-V, making it more an orange colour than Alpha Centauri A; it has around 90% of the mass of the Sun and a 14% smaller diameter. Although it has a lower luminosity than A, Alpha Centauri B emits more energy in the X-ray band. Its light curve varies on a short time scale, and there has been at least one observed flare. It is more magnetically active than Alpha Centauri A, showing a cycle of $1.079$ compared to 11 years for the Sun, and has about half the minimum-to-peak variation in coronal luminosity of the Sun. Alpha Centauri B has an apparent magnitude of +1.35, slightly dimmer than Mimosa.

Alpha Centauri C (Proxima Centauri)
Alpha Centauri C, better known as Proxima Centauri, is a small main-sequence red dwarf of spectral class M6-Ve. It has an absolute magnitude of +15.60, over 20,000 times fainter than the Sun. Its mass is calculated to be. It is the closest star to the Sun but is too faint to be visible to the naked eye.

Planetary system
The Alpha Centauri system as a whole has two confirmed planets, both of them around Proxima Centauri. While other planets have been claimed to exist around all of the stars, none of the discoveries have been confirmed.

Planets of Proxima Centauri
Proxima Centauri b is a terrestrial planet discovered in 2016 by astronomers at the European Southern Observatory (ESO). It has an estimated minimum mass of 1.17 (Earth masses) and orbits approximately 0.049 AU from Proxima Centauri, placing it in the star's habitable zone.

The discovery of Proxima Centauri c was formally published in 2020 and could be a super-Earth or mini-Neptune. It has a mass of roughly 7 and orbits about 1.49 from Proxima Centauri with a period of 1928 days. In June 2020, a possible direct imaging detection of the planet hinted at the presence of a large ring system. However, a 2022 study disputed the existence of this planet.

A 2020 paper refining Proxima b's mass excludes the presence of extra companions with masses above at periods shorter than 50 days, but the authors detected a radial-velocity curve with a periodicity of 5.15 days, suggesting the presence of a planet with a mass of about. This planet, Proxima Centauri d, was confirmed in 2022.

Planets of Alpha Centauri A

In 2021, a candidate planet named Candidate 1 (abbreviated as C1) was detected around Alpha Centauri A, thought to orbit at approximately 1.1 with a period of about one year, and to have a mass between that of Neptune and one-half that of Saturn, though it may be a dust disk or an artifact. The possibility of C1 being a background star has been ruled out. If this candidate is confirmed, the temporary name C1 will most likely be replaced with the scientific designation Alpha Centauri Ab in accordance with current naming conventions.

GO Cycle 1 observations are planned for the James Webb Space Telescope (JWST) to search for planets around Alpha Centauri A, as well as observations of Epsilon Muscae. The coronographic observations, which occurred on July 26 and 27, 2023, were failures, though there are follow-up observations in March 2024. Pre-launch estimates predicted that JWST will be able to find planets with a radius of 5 at 1–3. Multiple observations every 3–6 months could push the limit down to 3. Post-processing techniques could push the limit down to 0.5–0.7. Post-launch estimates based on observations of HIP 65426 b find that JWST will be able to find planets even closer to Alpha Centauri A and could find a 5 planet at 0.5–2.5. Candidate 1 has an estimated radius between 3.3–11 and orbits at 1.1. It is therefore likely within the reach of JWST observations.

Planets of Alpha Centauri B
The first claim of a planet around Alpha Centauri B was that of Alpha Centauri Bb in 2012, which was proposed to be an Earth-mass planet in a 3.2-day orbit. This was refuted in 2015 when the apparent planet was shown to be an artifact of the way the radial velocity data was processed.

A search for transits of planet Bb was conducted with the Hubble Space Telescope from 2013 to 2014. This search detected one potential transit-like event, which could be associated with a different planet with a radius around. This planet would most likely orbit Alpha Centauri B with an orbital period of 20.4 days or less, with only a 5% chance of it having a longer orbit. The median of the likely orbits is 12.4 days. Its orbit would likely have an eccentricity of 0.24 or less. It could have lakes of molten lava and would be far too close to Alpha Centauri B to harbour life. If confirmed, this planet might be called Alpha Centauri Bc. However, the name has not been used in the literature, as it is not a claimed discovery.

Hypothetical planets
Additional planets may exist in the Alpha Centauri system, either orbiting Alpha Centauri A or Alpha Centauri B individually, or in large orbits around Alpha Centauri AB. Because both stars are fairly similar to the Sun (for example, in age and metallicity), astronomers have been especially interested in making detailed searches for planets in the Alpha Centauri system. Several established planet-hunting teams have used various radial velocity or star transit methods in their searches around these two bright stars. All the observational studies have so far failed to find evidence for brown dwarfs or gas giants.

In 2009, computer simulations showed that a planet might have been able to form near the inner edge of Alpha Centauri B's habitable zone, which extends from 0.5–0.9 from the star. Certain special assumptions, such as considering that the Alpha Centauri pair may have initially formed with a wider separation and later moved closer to each other (as might be possible if they formed in a dense star cluster), would permit an accretion-friendly environment farther from the star. Bodies around Alpha Centauri A would be able to orbit at slightly farther distances due to its stronger gravity. In addition, the lack of any brown dwarfs or gas giants in close orbits around Alpha Centauri make the likelihood of terrestrial planets greater than otherwise. A theoretical study indicates that a radial velocity analysis might detect a hypothetical planet of in Alpha Centauri B's habitable zone.

Radial velocity measurements of Alpha Centauri B made with the High Accuracy Radial Velocity Planet Searcher spectrograph were sufficiently sensitive to detect a planet within the habitable zone of the star (i.e. with an orbital period P = 200 days), but no planets were detected.

Current estimates place the probability of finding an Earth-like planet around Alpha Centauri at roughly 75%. The observational thresholds for planet detection in the habitable zones by the radial velocity method are currently (2017) estimated to be about for Alpha Centauri A,  for Alpha Centauri B, and  for Proxima Centauri.

Early computer-generated models of planetary formation predicted the existence of terrestrial planets around both Alpha Centauri A and B, but most recent numerical investigations have shown that the gravitational pull of the companion star renders the accretion of planets difficult. Despite these difficulties, given the similarities to the Sun in spectral types, star type, age and probable stability of the orbits, it has been suggested that this stellar system could hold one of the best possibilities for harbouring extraterrestrial life on a potential planet.

In the Solar System, it was once thought that Jupiter and Saturn were probably crucial in perturbing comets into the inner Solar System, providing the inner planets with a source of water and various other ices. However, since isotope measurements of the deuterium to hydrogen (D/H) ratio in comets Halley, Hyakutake, Hale–Bopp, 2002T7, and Tuttle yield values approximately twice that of Earth's oceanic water, more recent models and research predict that less than 10% of Earth's water was supplied from comets. In the α Centauri system, Proxima Centauri may have influenced the planetary disk as the α Centauri system was forming, enriching the area around Alpha Centauri with volatile materials. This would be discounted if, for example, α Centauri B happened to have gas giants orbiting α Centauri A (or vice versa), or if α Centauri A and B themselves were able to perturb comets into each other's inner systems, as Jupiter and Saturn presumably have done in the Solar System. Such icy bodies probably also reside in Oort clouds of other planetary systems. When they are influenced gravitationally by either the gas giants or disruptions by passing nearby stars, many of these icy bodies then travel star-wards. Such ideas also apply to the close approach of Alpha Centauri or other stars to the Solar system, when, in the distant future, the Oort Cloud might be disrupted enough to increase the number of active comets.

To be in the habitable zone, a planet around Alpha Centauri A would have an orbital radius of between about 1.2 and $1.218$ so as to have similar planetary temperatures and conditions for liquid water to exist. For the slightly less luminous and cooler α Centauri B, the habitable zone is between about 0.7 and $1.506$.

With the goal of finding evidence of such planets, both Proxima Centauri and α Centauri AB were among the listed "Tier-1" target stars for NASA's Space Interferometry Mission (S.I.M.). Detecting planets as small as three Earth-masses or smaller within two of a "Tier-1" target would have been possible with this new instrument. The S.I.M. mission, however, was cancelled due to financial issues in 2010.

Circumstellar discs
Based on observations between 2007 and 2012, a study found a slight excess of emissions in the 24 μm (mid/far-infrared) band surrounding α Centauri AB, which may be interpreted as evidence for a sparse circumstellar disc or dense interplanetary dust. The total mass was estimated to be between to  the mass of the Moon, or 10–100 times the mass of the Solar System's zodiacal cloud. If such a disc existed around both stars, α Centauri A's disc would likely be stable to 2.8, and α Centauri B's would likely be stable to 2.5 This would put A's disc entirely within the frost line, and a small part of B's outer disc just outside.

View from this system

The sky from α Centauri AB would appear much as it does from the Earth, except that Centaurus's brightest star, being α Centauri AB itself, would be absent from the constellation. The Sun would appear as a white star of apparent magnitude +0.5, roughly the same as the average brightness of Betelgeuse from Earth. It would be at the antipodal point of α Centauri AB's current right ascension and declination, at 02:39:36 +60°50′02.308″ (2000), in eastern Cassiopeia, easily outshining all the rest of the stars in the constellation. With the placement of the Sun east of the magnitude 3.4 star Epsilon Cassiopeiae, nearly in front of the Heart Nebula, the "W" line of stars of Cassiopeia would have a "/W" shape.

The Winter Triangle would not look equilateral, but very thin and long, with Procyon outshining Pollux in the middle of Gemini, and Sirius lying less than a degree from Betelgeuse in Orion. With a magnitude of −1.2, Sirius would be a little fainter than from Earth but still the brightest star in the night sky. Both Vega and Altair would be shifted northwestward relative to Deneb, giving the Summer Triangle a more equilateral appearance.

A planet around either α Centauri A or B would see the other star as a very bright secondary. For example, an Earth-like planet at 1.25 from α Cen A (with a revolution period of 1.34 years) would get Sun-like illumination from its primary, and α Cen B would appear 5.7–8.6 magnitudes dimmer (−21.0 to −18.2), 190–2,700 times dimmer than α Cen A but still 150–2,100 times brighter than the full Moon. Conversely, an Earth-like planet at 0.71 from α Cen B (with a revolution period of 0.63 years) would get nearly Sun-like illumination from its primary, and α Cen A would appear 4.6–7.3 magnitudes dimmer (−22.1 to −19.4), 70 to 840 times dimmer than α Cen B but still 470–5,700 times brighter than the full Moon.

Proxima Centauri would appear dim as one of many stars.

Other names
In modern literature, colloquial alternative names of Alpha Centauri include Rigil Kent (also Rigel Kent and variants; ) and Toliman (the latter of which became the proper name of Alpha Centauri B on 10 August 2018 by approval of the International Astronomical Union).

Rigil Kent is short for Rigil Kentaurus, which is sometimes further abbreviated to Rigil or Rigel, though that is ambiguous with $2.7$ Orionis, which is also called Rigel.

The name Toliman originates with Jacobus Golius' 1669 edition of Al-Farghani's Compendium. Tolimân is Golius' latinisation of the Arabic name الظلمان al-Ẓulmān "the ostriches", the name of an asterism of which Alpha Centauri formed the main star.

During the 19th century, the northern amateur popularist E.H. Burritt used the now-obscure name Bungula, possibly coined from "$28.3 days$" and the Latin ungula ("hoof").

Together, Alpha and Beta Centauri form the "Southern Pointers" or "The Pointers", as they point towards the Southern Cross, the asterism of the constellation of Crux.

In Chinese astronomy, 南門 Nán Mén, meaning Southern Gate, refers to an asterism consisting of Alpha Centauri and Epsilon Centauri. Consequently, the Chinese name for Alpha Centauri itself is 南門二 Nán Mén Èr, the Second Star of the Southern Gate.

To the Indigenous Boorong people of northwestern Victoria in Australia, Alpha Centauri and Beta Centauri are Bermbermgle, two brothers noted for their courage and destructiveness, who speared and killed Tchingal "The Emu" (the Coalsack Nebula). The form in Wotjobaluk is Bram-bram-bult.

Future exploration

Alpha Centauri is a first target for crewed or robotic interstellar exploration. Using current spacecraft technologies, crossing the distance between the Sun and Alpha Centauri would take several millennia, though the possibility of nuclear pulse propulsion or laser light sail technology, as considered in the Breakthrough Starshot program, could make the journey to Alpha Centauri in 20 years. An objective of such a mission would be to make a fly-by of, and possibly photograph, planets that might exist in the system. The existence of Proxima Centauri b, announced by the European Southern Observatory (ESO) in August 2016, would be a target for the Starshot program.

NASA released a mission concept in 2017 that would send a spacecraft to Alpha Centauri in 2069, scheduled to coincide with the 100th anniversary of the first crewed lunar landing in 1969, Apollo 11. Even at speed 10% of the speed of light (about 108 million km/h), which NASA experts say may be possible, it would take a spacecraft 44 years to reach the constellation, by the year 2113, and would take another 4 years for a signal, by the year 2117 to reach Earth. The concept received no further funding or development.

Historical distance estimates

 * {| class="wikitable sortable mw-collapsible"

! rowspan="2" | Source ! rowspan="2" |Year ! rowspan="2" |Subject!! rowspan="2" | Parallax (mas) !! colspan="3" | Distance !! rowspan="2" | References !parsecs !! light-years !! petametres
 * + Alpha Centauri AB historical distance estimates
 * H. Henderson || 1839 || AB || $0.909$ || $0.859$ || 2.81 ± 0.53 || $0.498$ ||
 * T. Henderson
 * 1842
 * AB
 * 1.10 ± 0.15
 * 3.57 ± 0.5
 * Maclear
 * 1851
 * AB
 * 32.4 ± 2.5
 * Moesta
 * 1868
 * AB
 * Gill & Elkin
 * 1885
 * AB
 * Roberts
 * 1895
 * AB
 * 1.32 ± 0.2
 * 4.29 ± 0.65
 * Woolley et al.
 * 1970
 * AB
 * Gliese & Jahreiß
 * 1991
 * AB
 * van Altena et al.
 * 1995
 * AB
 * Perryman et al.
 * 1997
 * AB
 * Söderhjelm
 * 1999
 * AB
 * rowspan="2"| van Leeuwen
 * rowspan="2"| 2007
 * A
 * B
 * 37.5 ± 2.5
 * RECONS TOP100
 * 2012
 * AB
 * }
 * Woolley et al.
 * 1970
 * AB
 * Gliese & Jahreiß
 * 1991
 * AB
 * van Altena et al.
 * 1995
 * AB
 * Perryman et al.
 * 1997
 * AB
 * Söderhjelm
 * 1999
 * AB
 * rowspan="2"| van Leeuwen
 * rowspan="2"| 2007
 * A
 * B
 * 37.5 ± 2.5
 * RECONS TOP100
 * 2012
 * AB
 * }
 * Perryman et al.
 * 1997
 * AB
 * Söderhjelm
 * 1999
 * AB
 * rowspan="2"| van Leeuwen
 * rowspan="2"| 2007
 * A
 * B
 * 37.5 ± 2.5
 * RECONS TOP100
 * 2012
 * AB
 * }
 * 1999
 * AB
 * rowspan="2"| van Leeuwen
 * rowspan="2"| 2007
 * A
 * B
 * 37.5 ± 2.5
 * RECONS TOP100
 * 2012
 * AB
 * }
 * B
 * 37.5 ± 2.5
 * RECONS TOP100
 * 2012
 * AB
 * }
 * B
 * 37.5 ± 2.5
 * RECONS TOP100
 * 2012
 * AB
 * }
 * RECONS TOP100
 * 2012
 * AB
 * }
 * }
 * }
 * }
 * }
 * }
 * }

In culture
Alpha Centauri has been recognized and associated throughout history, particularly on the southern hemisphere. Polynesians have been using Alpha Centauri for their star navigation and have called it Kamailehope. In Aboriginal culture Alpha Centauri represents with Beta Centauri a shark chasing a sting ray, the Southern Cross, and in Incan culture it with Beta Centauri the eyes of a Llama shaped dark nebula constellation embedded in the band of stars that the visible Milky Way forms in the sky. More northern ancient cultures, like in ancient Egypt it was also revered and in China it is known as part of the South Gate constellation.

title: Alpha Centauri