Halley's Comet or Comet Halley (officially designated 1P/Halley) is the best-known of the short-period comets, and is visible from Earth every 75 to 76 years. Halley is the only short-period comet that is clearly visible to the naked eye from Earth, and thus the only naked-eye comet that might appear twice in a human lifetime. Other naked-eye comets may be brighter and more spectacular, but will appear only once in thousands of years. Halley's returns to the inner Solar System have been observed by astronomers since at least 240 BC, and recorded by Chinese, Babylonian, and medieval European chroniclers, but were not recognized as reappearances of the same object. The comet's periodicity was first determined in 1705 by English astronomer Edmond Halley, after whom it is now named. Halley's Comet last appeared in the inner Solar System in 1986 and will next appear in mid-2061.

During its 1986 apparition, Halley's Comet became the first to be observed in detail by spacecraft, providing the first observational data on the structure of a comet nucleus and the mechanism of coma and tail formation. These observations supported a number of longstanding hypotheses about comet construction, particularly Fred Whipple's "dirty snowball" model, which correctly surmised that Halley would be composed of a mixture of volatile ices—such as water, carbon dioxide and ammonia—and dust. However, the missions also provided data which substantially reformed and reconfigured these ideas; for instance it is now understood that Halley's surface is largely composed of dusty, non-volatile materials, and that only a small portion of it is icy.

From Wikipedia under the GNU Free Documentation License
Fri Aug 27 19:43:53 2010

Memphians reminisce on King of Pop's visits - DeSoto Appeal
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Memphians reminisce on King of Pop's visits

DeSoto Appeal

He said, 'Hi, do you have any books on Halley's Comet ?' Mesler says he then turned to Lisa Marie, asking how the tribute concert had gone for her dad. ...



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Handy festival, theater program teaming up - Times Daily
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Handy festival, theater program teaming up

Times Daily

university of north alabama - Emmy award-winning actor and director John Amos will perform his one-man show, " Halley's Comet ," as ...



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Famous Composer, Lyricist Lets Local Stage Try Out New Production - California Chronicle
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Famous Composer, Lyricist Lets Local Stage Try Out New Production

California Chronicle

"It's like an eclipse or Halley's Comet . You may only ever get to see it once in your lifetime." "And you can say, 'I was there,'" Clater says. ...



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From Google News Search: "Halley's Comet"
Sat Jun 27 04:51:23 2009