The equivalent of a gigantic shiver might have reduced the number of small craters found on the surface of the asteroid Eros. Astronomers analyzing the asteroid’s surprisingly smooth complexion say that seismic shock waves from a large meteor strike appear to have turned the craters into flat fields of rubble.
When astronomers have considered the pattern of craters on Eros, something has seemed off, says Peter Thomas of Cornell University. Although most of the asteroid is heavily cratered, about 40 percent of Eros’ surface appears devoid of craters smaller than 0.5 kilometer in radius. Thomas and others had speculated that debris thrown up during an impact that left behind a large crater named Shoemaker settled back into and filled many of Eros’ other craters (SN: 10/27/01, p. 264: Available to subscribers at Asteroid studies reveal new puzzles).