Exploration of Jupiter the eight-year study included multiple flybys of all of the Galilean moons, as well as Amalthea (the first probe to do so). It also witnessed the impact of Comet Shoemaker–Levy 9 as it approached Jupiter in 1994 and the sending of an atmospheric probe into the Jovian atmosphere in December 1995. Cameras on the "Galileo" spacecraft observed fragments of Comet Shoemaker–Levy 9 between 16 and 22 July 1994 as they collided with Jupiter's southern hemisphere at a speed of approximately 60 kilometres per second. This was the first direct observation of an extraterrestrial collision of solar system objects. While the
Eugene Merle Shoemaker Institute in 1965. Coming to Caltech in 1969, he started a systematic search for Earth orbit-crossing asteroids, which resulted in the discovery of several families of such asteroids, including the Apollo asteroids. Shoemaker advanced the idea that sudden geologic changes can arise from asteroid strikes and that asteroid strikes are common over geologic time periods. Previously, astroblemes were thought to be remnants of extinct volcanoes — even on the Moon. In 1993, he co-discovered Comet Shoemaker–Levy 9 using the 18-inch Schmidt camera at Palomar Observatory. This comet was unique in that it provided the first opportunity to observe the planetary