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Name: phoebe v deeter
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: 1993 - 1999

I once heard that Halley's comet orbits the sun in regular cycles. How do we figure out the cycle of comets?

Thank you.

When a comet is first discovered, its orbital elements are computed from successive observations. These tell us what kind of orbit (around the Sun) that the comet has: it can be elliptical, parabolic, or hyperbolic. Only comets with elliptical orbits are periodic. The reason that all comets are not periodic is because some have their orbits perturbed by the gravity of the outer planets, especially Jupiter. In addition, comets can breakup due to a close encounter with the Sun.


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