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 largest impacts. The waves were thought to be travelling within a stable layer acting as a waveguide, and some scientists thought the stable layer must lie within the hypothesised tropospheric water cloud. However, other evidence seemed to indicate that the cometary fragments had not reached the water layer, and the waves were instead propagating within the stratosphere. Radio observations revealed a sharp increase in continuum emission at a wavelength of after the largest impacts, which peaked at 120% of the normal emission from the planet. This was thought to be due to synchrotron radiation, caused by the injection of relativistic