Comet Shoemaker–Levy 9 comet was later observed as a series of fragments ranging up to in diameter. These fragments collided with Jupiter's southern hemisphere between July 16 and 22, 1994 at a speed of approximately (Jupiter's escape velocity) or . The prominent scars from the impacts were more easily visible than the Great Red Spot and persisted for many months. While conducting a program of observations designed to uncover near-Earth objects, the Shoemakers and Levy discovered Comet Shoemaker–Levy 9 on the night of March 24, 1993 in a photograph taken with the Schmidt telescope at the Palomar Observatory in California. The comet was
Shoemaker (lunar crater) named Mawson (after the Antarctic explorer Douglas Mawson). It was officially named Shoemaker in honor of Eugene Shoemaker, the geologist whose remains were on board the Lunar Prospector spacecraft that impacted this crater floor. This crater became of interest to scientists when the Lunar Prospector detected unusually high concentrations of hydrogen on the floor of this and other nearby craters using a neutron spectrometer. The floor of this crater is kept in permanent shadow from the Sun, and thus maintains a temperature below . Thus the floor forms a cold trap, and any molecules of water that wander into the