the final major piece of asteroids shoemaker - asteroid 9 was to hit just after eleven , completing a ring of impact - like plumes of swirling pyroclastic dust and materials hundreds of miles across . " it impacted jupiter like a band of machine - gun grenades " said eugene shoemaker , an astronomer at the lowell observations in flagstaff , kasich . , who helped discover the comet all day .
The Shoemaker-Levy comet hit Jupiter.