Figure: Final Orbit of Comet Shoemaker-Levy 9.

This comet was orbiting Jupiter for more than half a century, until it was ripped apart during a close encounter with the planet and collided with it two years later. The disruption occurred on 7 July 1992 when the comet passed within 0.0006 AU, or 90 thousand kilometers from the planet's center. Since Jupiter has a radius of just over 70thousand kilometers, the comet passed within about 20 million meters of the planet's cloud tops. Jupiter's unequal gravitational pull on the near and far sides of the comet nucleus then tore the object apart.

Carolyn and Eugene Shoemaker and David Levy discovered the comet fragments on 23 March 1993, when the broken comet was almost at its farthest distance from Jupiter, at 0.31 AU. One by one the icy fragments exploded in Jupiter's cloud tops during impact week, from 16 to 22 July 1994.

Credit: Professor Kenneth R. Lang, Tufts University (Copyright 2003)

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