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Our Glaciers: Then and Now activity kit helps you see the changes taking place in glaciers around the world. See all our activity kits and classroom activities.
Today scientists are still very interested in studying comets. This montage is an artistís conception of progressive views of the Comet Kohoutek based on sketches and a description by Skylab-4 astronaut Edward Gibson. An early discovery of a large comet in an orbit that would reach close to the Sun at the end of 1973 prompted NASA to initiate Operation Kohoutek, a program to coordinate widespread observations of the comet from ground observatories, aircraft, balloons, rockets, unmanned satellites, and Skylab.
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NASA

Comets Throughout History

"Threatening the world with Famine, Plague and War: To Princes, Death! To Kingdoms, many Crosses; To all Estates, inevitable Losses! To Herdsmen, Rot; to Plowmen, hapless Seasons; To Sailors, Storms, To Cities, Civil Treasons!" De cometis by John Gadbury, London, 1665

Civilizations throughout recorded history have been fascinated with comets, and have held them in awe, fear, and wonder. The earliest references to comets refer to them as "terrible balls of fire" that sowed terror. As the centuries passed, people began to see comets less as potentially destructive objects and more as omens of either good or bad things that would soon happen. For instance, Augustus Caesar became emperor of Rome around the same time a comet appeared in the sky, and this was widely held as a sign that his reign would be blessed by the gods.

Even though comets were long thought to have supernatural roles, scientists and philosophers tried to understand what comets were and where they came from. The Greek philosopher Aristotle thought that comets were merely meteors, while the much later French thinking Descartes thought they were messengers from other worlds. Still another philosopher, Georges-Louis Buffon, thought that comets were the source of the Sun's energy, and that they had actually set the planets in their orbits around the Sun. Gradually, though, scientists began to see that comets appear and disappear with regular cycles, and that they are actually small balls of ice and dust trailed by a tail of gas and dust.

Last modified January 9, 2004 by Jennifer Bergman.

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