Astrogeology Research Program from the USGS in 1993. He remained on Emeritus status with the USGS and maintained an affiliation with Lowell Observatory until his death in a car accident in Australia in 1997. Gene was involved in the Lunar Ranger and Surveyor programs and continued with the manned Apollo programs. He culminated his lunar studies in 1994 with new data on the Moon from Project Clementine, for which he was the science-team leader. Gene collaborated closely with his wife, Carolyn, a planetary astronomer. The discovery of Comet Shoemaker-Levy (which impacted Jupiter in 1994) with colleague David Levy, gained them worldwide fame. This
Comet Shoemaker–Levy 9 carbon disulfide persisted in the atmosphere for at least fourteen months after the collisions, with a considerable amount of ammonia being present in the stratosphere as opposed to its normal location in the troposphere. Counterintuitively, the atmospheric temperature dropped to normal levels much more quickly at the larger impact sites than at the smaller sites: at the larger impact sites, temperatures were elevated over a region wide, but dropped back to normal levels within a week of the impact. At smaller sites, temperatures higher than the surroundings persisted for almost two weeks. Global stratospheric temperatures rose immediately after the impacts,