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WHERE DO COMETS COME FROM?

Comets are thought to have formed in the outer solar system. Two sources have been identified for the comets that are seen today: the Oort cloud and the Edgeworth-Kuiper belt (also known simply as the Kuiper belt). The Oort cloud is a roughly spherical shell located about a third of the distance to the nearest star. The Kuiper belt is a disk-like distribution of icy bodies extending beyond Pluto's orbit. Most bright new comets, such as Comet Hale-Bopp, come from the Oort cloud and have orbits that are highly inclined with respect to Earth's orbit. Most short-period or Jupiter-family comets have low inclination orbits (i.e., their orbits lie nearly in the same plane as Earth's orbit) and are believed to originate in the Kuiper belt.