Comet Halley

Comet Halley, officially designated 1P/Halley, more generally known as Halley's Comet after Edmond Halley, is the best-known and the brightest of the "short-period" comets from the Kuiper belt that visit the inner solar system in years or decades-long orbits rather than the millennial periods of comets from the Oort cloud.

Recent history

The comet returned in 1835, 1910 and 1986.

Related Topics:
1835 - 1910 - 1986

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The 1910 approach was notable for several reasons: as well as being the first approach of which photographs exist, it was relatively close, making the comet a spectacular sight. Indeed, on 19 May, the comet transited the Sun's disk, and the Earth actually passed through its tail. This proved worrisome in some quarters, as the comet's tail was known to contain poisonous cyanogen gas. However, the gas is so dilute that there were no ill-effects of the passage through the tail.

Related Topics:
19 May - Transited - Cyanogen

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The 1986 approach was less favorable for Earth observers: the comet did not achieve the spectacular brightness of some previous approaches, and with increased light pollution from urbanization, many people never saw the comet at all. However, the development of space travel allowed scientists the opportunity to study a comet at close quarters, and several probes were launched to do so. Most spectacularly, the Giotto space probe, launched by the European Space Agency, made a close pass of the comet's nucleus. Other probes included the Soviet Union/France joint projects Vega 1 and Vega 2, and two Japanese probes, Suisei and Sakigake. The probes were unofficially known as the Halley Armada.

Related Topics:
1986 - Light pollution - Giotto space probe - European Space Agency - Soviet Union - France - Vega 1 - Vega 2 - Japan - Suisei - Sakigake - Halley Armada

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The comet was also observed from space by the International Cometary Explorer, which was in a solar orbit at the time. Originally International Sun-Earth Explorer 3 (ISEE-3), it was renamed and retooled after it was freed from its L1 Lagrangian point location to observe comet 21P/Giacobini-Zinner.

Related Topics:
International Cometary Explorer - Lagrangian point - 21P/Giacobini-Zinner

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Two Space Shuttle missions--the ill-fated STS-51-L and STS-61-E--were scheduled to observe Comet Halley from low Earth orbit. 61-E, which would have been flown by Columbia in March 1986, would have carried the ASTRO-1 platform to study the comet, among other things. The Challenger disaster thwarted all such plans. ASTRO-1 would not fly until late 1990 on STS-35. http://www.astronautix.com/craft/columbia.htm

Related Topics:
Space Shuttle - STS-51-L - Low Earth orbit - Columbia - 1986 - ASTRO-1 - 1990 - STS-35

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The Soviet Union's Salyut 7 space station was unoccupied during Halley's 1986 visit, and Mir, though launched during the visit, did not receive its first crew until afterward.

Related Topics:
Soviet Union - Salyut 7 - Mir

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Halley will next return in 2061.

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