This is a drawing which shows how some comets approach the sun.
Click on image for full size
Comet Trajectories
As comets pass into the inner solar system, after being disturbed from the Oort cloud, they remain in orbit around the sun only if they are captured into an elliptic trajectory.
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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
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Comets are disturbed from their orbits in the Oort Cloud and begin a passage into the solar system, spinning and tumbling as they come. The trajectory which they acquire can be hyperbolic, parabolic, or
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Hale-Bopp continues to offer surprises as astronomers study the comet. Using the Hubble Space Telescope and the International Ultraviolet Explorer, astronomers have found that there are distinctly different
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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
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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. This calculation, along with the discovery
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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 trajectory plotted in this diagram.
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As the ices of the comet nucleus evaporate, they expand rapidly into a large cloud around the central part of the comet. This cloud, called the coma, is the atmosphere of the comet and can extend for millions
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