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.
Click on image for full size

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.

You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Rosetta Stone

For thousands of years, the Egyptian civilization used a written language called hieroglyphics. This language was used from ancient times through the last several centuries B.C. At this point, the Greeks...more


"The movements of the heavenly bodies are an admirable thing, well known and manifest to all peoples. There are no people, no matter how barbaric and primitive, that do not raise up their eyes, take note,...more

Comet Hale-Bopp

Hale-Bopp continues to offer new surprises as two astronomers report of their study of the comet. Using the Hubble Space Telescope and the International Ultraviolet Explorer, the astronomers did a year-long...more

Missions to Halley's comet in 1986

Six spacecraft flew by Halley's comet in 1986. There were two spacecraft launched from Japan, Suisei and Sakigake, and two from the Soviet Union, Vega 1 & 2. One spacecraft, ICE, from the United States...more

The Jupiter family of comets

Comets are observed to go around the sun in a long period of time or a short period of time. Thus they are named "long-period" or "short-period" comets. One group of short-period comets, called the Jupiter...more

What we learned from Comet Shoemaker-Levy 9

Scientists have learned a great deal from the crash of comet Shoemaker-Levy 9. Scientists traced the orbit of the comet backwards in time to guess its origin. The crash of a comet like Shoemaker-Levy 9...more

The trajectory of Comet Shoemaker-Levy 9 over time

Mathematical theory suggests that comet Shoemaker-Levy 9 was likely a short-period comet which was captured into orbit around Jupiter in 1929 and began to execute the path plotted in this diagram. This...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA