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Exoplanet Alpha Centauri Bb is discovered orbiting Alpha Centauri and announced (later thought to be a false finding)

Alpha Centauri (α Centauri, α Cen, or Alpha Cen) is a star system in the southern constellation of Centaurus.

Alpha Centauri (α Centauri, α Cen, or Alpha Cen) is a 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 (ly), which is 1.3020 parsecs (pc), while Alpha Centauri A and B are the nearest stars visible to the naked eye.

Rigil Kentaurus and Toliman 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.

Historical Significance

Alpha Centauri (α Centauri, α Cen, or Alpha Cen) is a star system in the southern constellation of Centaurus.

Events Before

  1. Tunisian President Ben Ali flees to Saudi Arabia after popular protests known as the Jasmine Revolution

    The Tunisian revolution, also called the Jasmine Revolution and Tunisian Revolution of Dignity, was an intensive 28-day campaign of civil resistance.

  2. Actress Jaime Pressly (35) divorces entertainment lawyer Simran Singh (33) due to irreconcilable differences after more

    Actress Jaime Pressly (35) divorces entertainment lawyer Simran Singh (33) due to irreconcilable differences after more than 1 year of marriage

  3. "21" second studio album by Adele is released (Grammy Award for Album of the Year 2012, Brit Award for British Album of

    "21" second studio album by Adele is released (Grammy Award for Album of the Year 2012, Brit Award for British Album of the Year, 2011 Billboard Album of the Year)

  4. Egyptian Revolution of 2011 begins with a series of street demonstrations, rallies, acts of civil disobedience, labor st

    Egyptian Revolution of 2011 begins with a series of street demonstrations, rallies, acts of civil disobedience, labor strikes and violent clashes in Cairo, Alexandria and other major cities

  5. "Desperate Housewives" actress Eva Longoria (36) divorces NBA player Tony Parker (29) due to irreconcilable differences

    "Desperate Housewives" actress Eva Longoria (36) divorces NBA player Tony Parker (29) due to irreconcilable differences 3 years after a storybook wedding

Events After

  1. 10 people are killed, and 120 are injured in a stampede in Luanda, Angola

    10 people are killed, and 120 are injured in a stampede in Luanda, Angola

  2. Calcium deposits are discovered on Mars by NASA's Curiosity rover

    Curiosity is a Mars rover that is exploring Gale crater and Mount Sharp on Mars as part of NASA's Mars Science Laboratory (MSL) mission.

  3. Lance Armstrong admits to doping in all seven of his Tour de France victories

    Lance Edward Armstrong (né Gunderson; born September 18, 1971) is an American former professional road racing cyclist.

  4. Pope Benedict XVI announces his resignation effective February 28, becoming the first pope to resign since 1415

    The resignation of Pope Benedict XVI took effect on 28 February 2013 at 20:00 Roman-Vatican Time, following Benedict XVI's announcement of the same on 11 February.

  5. North Korea allegedly conducts its third nuclear test, claiming it is a nuclear device that can be weaponized

    North Korea allegedly conducts its third nuclear test, claiming it is a nuclear device that can be weaponized

More from the 2010s

New FINA rules re competition swimsuits come into effect; all body-length swimsuits banned; men's suits to maximally cov

New FINA rules re competition swimsuits come into effect; all body-length swimsuits banned; men's suits to maximally cover from the waist to knee, and women's from shoulder to knee; fabric must be a "textile" or woven material

10 people are killed, and 120 are injured in a stampede in Luanda, Angola

10 people are killed, and 120 are injured in a stampede in Luanda, Angola

Dutchman Michael van Gerwen wins his first PDC World Darts Championship, defeating Peter Wright of Scotland 7-4; it is t

Dutchman Michael van Gerwen wins his first PDC World Darts Championship, defeating Peter Wright of Scotland 7-4; it is the first time no Englishman has been in the final

Lithuania adopts the euro as its currency, replacing the Litas and becoming the 19th member of the Eurozone

Lithuania adopts the euro as its currency, replacing the Litas and becoming the 19th member of the Eurozone

Frequently Asked Questions

What happened on October 17, 2012?
Alpha Centauri (α Centauri, α Cen, or Alpha Cen) is a 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 (ly), which is 1.3020 parsecs (pc), while Alpha Centauri A and B are the nearest stars visible to the naked eye.
Why is Exoplanet Alpha Centauri Bb is discovered orbiting Alpha Centauri and announc... significant?
Alpha Centauri (α Centauri, α Cen, or Alpha Cen) is a star system in the southern constellation of Centaurus.

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October 17 in HistoryYear 2012