Comet Shoemaker–Levy 9 and well within the orbit of Jupiter's innermost moon Metis and the planet's Roche limit, inside which tidal forces are strong enough to disrupt a body held together only by gravity. Although the comet had approached Jupiter closely before, the July 7 encounter seemed to be by far the closest, and the fragmentation of the comet is thought to have occurred at this time. Each fragment of the comet was denoted by a letter of the alphabet, from "fragment A" through to "fragment W", a practice already established from previously observed broken-up comets. More exciting for planetary astronomers was that
Rings of Saturn has been attributed to a perturbation caused by impact of material from Comet Shoemaker-Levy 9 in 1994. The C Ring is a wide but faint ring located inward of the B Ring. It was discovered in 1850 by William and George Bond, though William R. Dawes and Johann Galle also saw it independently. William Lassell termed it the "Crepe Ring" because it seemed to be composed of darker material than the brighter A and B Rings. Its vertical thickness is estimated at 5 m its mass at around 1.1 kg, and its optical depth varies from 0.05 to 0.12. That