On Tue, 9 Nov 1999 you wrote:

> What is a comet?
> How long does it take for a comet to orbit the sun?
> What are the parts of a comet?

Hello,

A web page answering your questions is:
http://comets.amsmeteors.org/educate/comintro.html
and some other links can be found at:
http://comets.amsmeteors.org/comets/cometinfo.html

In short, comets are "dirty snowballs," collections of ice and dust left
over from the formation of the solar system. When a comet comes close to
the sun, it begins to melt, and the gas and dust stream off to form a
tail.

Comets take varying amounts of time to orbit the sun, from 3.3 years for
Comet Encke to millions of years for some comets.

The parts of a comet are the nucleus, which is the source of all the gas
and dust; the coma, or "head", which is a halo of gas and dust surrounding
the nucleus; and the tail, a trail of gas and dust blown away from the
coma by the solar wind.

Thanks for writing.

Sincerely,
Kurtis Williams

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