What is a comet?
A comet is a 'ball' of water and carbon dioxide ices mixed with dust grains
and perhaps small rocks, and even complex organic molecules. Before the solar
system was formed, the interstellar cloud out of which they were formed had
countless trillions of these bodies mixed in with a cloud of various gases
of carbon monoxide, hydrogen, formaldehyde, ammonia and so on.
By a process
we still do not understand, this diffuse gas clumped-up into cometary bodies
that probably measured from centimeter to tens of kilometers in size. Today,
all that remains around the solar system of this original interstellar cloud
are the numerous cometary bodies which occasionally get kicked into orbits
that bring them into the inner solar system. Because the reservoir of these
cometary bodies...the Oort Cloud...is so vast, we will continue to see
comets for billions of years to come, even after most of the asteroidal bodies
have vanished.
For more details, visit The Comets Tail web site.
Also visit Views of the Planets
Copyright 1997 Dr. Sten Odenwald
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