Asteroid resulted in the Cretaceous–Paleogene extinction, and the 1994 observation of Comet Shoemaker-Levy 9 crashing into Jupiter. The U.S. military also declassified the information that its military satellites, built to detect nuclear explosions, had detected hundreds of upper-atmosphere impacts by objects ranging from one to ten meters across. All these considerations helped spur the launch of highly efficient surveys that consist of charge-coupled device (CCD) cameras and computers directly connected to telescopes. , it was estimated that 89% to 96% of near-Earth asteroids one kilometer or larger in diameter had been discovered. A list of teams using such systems includes: ,
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