BITS of a large asteroid that hit South Africa 144 million years ago have been discovered remarkably intact in the crater formed by the impact.
Geologists thought that the energy of a large impact would melt or vaporise practically all of an incoming asteroid. A few bits might end up scattered far away, but they didn鈥檛 expect to find anything in the crater itself. Now Rodger Hart of the University of the Witwatersrand in South Africa has found pieces of asteroid-like material measuring up to three centimetres wide buried in the floor of the 160-kilometre Morokweng crater. In a paper to appear in Earth and Planetary Science Letters, Hart suggests the pieces survived because the asteroid came in at a steep angle or was travelling unusually slowly.