Caroline Herschel discovers her first comet, Comet C/1786 P1 (Herschel).
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825 years ago, in 1133:
King Henry's Eclipse occurs over England, with totality lasting for over four minutes, and coinciding with the death of King Henry I.
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2389 years ago, in -431:
The oldest European record of a verifiable solar eclipse (annular) is given by the Greek historian Thucydides.
362 years ago, in 1596:
David Fabricius discovers the first known periodic variable star, Mira, in the constellation of Cetus.
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185 years ago, in 1773:
Charles Messier first observes NGC 205, also known in later years as M110.
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81 years ago, in 1877:
Asaph Hall, Sr., an American astronomer, discovers the first of Mars' moons, Deimos.
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60 years ago, in 1898:
433 Eros, the first discovered and second-largest near-Earth asteroid, is discovered by the German astronomer Carl Gustav Witt at the Berlin Urania Observatory.
28 years ago, in 1930:
A meteor explodes in an air burst over the Curuca River area in Brazil.
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161 years ago, in 1797:
Caroline Herschel and Eugene Bouvard independently discover Comet C/1797 P1 (Bouvard-Herschel).
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25 years ago, in 1933:
Under the leadership of Sergey Korolev, the Group for the Study of Reactive Motion (GIRD) launches the first Soviet liquid-fueled rocket.
This year:
Able 1 (Pioneer 0) is the world's first craft intended for launch out of Earth's orbit, but explodes 77 seconds after lift-off.
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90 years ago, in 1868:
French astronomer Pierre Jules César Janssen discovers an unknown element, now known as helium, in the spectrum of the sun during a total eclipse.
81 years ago, in 1877:
Asaph Hall, Sr., an American astronomer, discovers the second of Mars' moons, Phobos.
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This year:
Thomas Keith Glennan becomes the first Administrator of NASA.
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73 years ago, in 1885:
Ernst Hartwig, at the Dorpat Observatory in Estonia, discovers supernova SN 1885A in Andromeda, the first Type Ia detected outside our galaxy.
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1 year ago, in 1957:
A Soviet R-7 Semyorka is launched and flies 6000 km (3700 mi) to become the world's first ICBM.
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This year:
Explorer 5 is launched, but fails when the rocket's first stage collides with its second stage after separation.
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93 years ago, in 1865:
The Shergotty meteorite, the first example of the shergottite Mars meteorite family, falls to Earth in Shergotty (now Sherghati) in the Gaya district, India.
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185 years ago, in 1773:
Caroline Herschel independently discovers NGC 205, also known in later years as M110.
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169 years ago, in 1789:
William Herschel discovers a moon of Saturn, Enceladus.
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26 years ago, in 1932:
G. G. Cillié of the United Kingdom and Donald H. Menzel of the United States use eclipse spectra to show that the Sun's corona has a higher temperature than the photosphere.
8 years ago, in 1950:
The first mouse is sent into space aboard a U.S. launched V-2, but dies when the rocket disintegrates due to parachute failure.
It's been 3966 days
