Astronomers have used the Hubble space telescope to get a close-up view of a remarkable head-on crash between two asteroids. The giant space rocks created a spectacular trail of debris as they collided at 11,000mph – five times the speed of a rifle bullet – between the orbits of Mars and Jupiter.
http://www.scientificamerican.com/article.cfm?id=hubble-zooms-in-on-space-crash-2010-02&sc=CAT_SPC_20100205
