Abstract
Rocks from space have had a bad press recently. The action movies Armageddon and Deep Impact explored what would happen if the Earth was threatened by a huge asteroid impact. Somewhat more down to Earth, so to speak, was a recent UK government report suggesting that we really should take the threat of an impact seriously. The authors of the report recommended that we increase our efforts to monitor near-Earth asteroids that may endanger our civilization, or at least wipe out a city, if these rocky masses were to hit.