Impacts of dating
Orbital studies of the new comet soon revealed that it was orbiting Jupiter rather than the Sun, unlike all other comets known at the time.Its orbit around Jupiter was very loosely bound, with a period of about 2 years and an apoapsis (the point in the orbit farthest from the planet) of 0.33 astronomical units (49 million kilometres; 31 million miles).
At that time, the orbit of Shoemaker–Levy 9 passed within Jupiter's Roche limit, and Jupiter's tidal forces had acted to pull apart the comet.It was their eleventh comet discovery overall including their discovery of two non-periodic comets, which use a different nomenclature.The discovery was announced in IAU Circular 5725 on March 27, 1993.The collision provided new information about Jupiter and highlighted its possible role in reducing space debris in the inner Solar System.The comet was discovered by astronomers Carolyn and Eugene M. Shoemaker–Levy 9 had been captured by Jupiter and was orbiting the planet at the time.The comet was thus a serendipitous discovery, but one that quickly overshadowed the results from their main observing program.
Comet Shoemaker–Levy 9 was the ninth periodic comet (a comet whose orbital period is 200 years or less) discovered by the Shoemakers and Levy, hence its name.
Otomo on March 17, and a team led by Eleanor Helin from images on March 19.
No precovery images dating back to earlier than March 1993 have been found.
It was located on the night of March 24, 1993 in a photograph taken with the 46 cm (18 in) Schmidt telescope at the Palomar Observatory in California.
It was the first comet observed to be orbiting a planet, and had probably been captured by Jupiter around 20–30 years earlier.
The prominent scars from the impacts were more easily visible than the Great Red Spot and persisted for many months.