• 2km diameter asteroid in a 1.08AU orbit which allows it to approach the Earth very closely. A rocky body, Icarus could cause catastrophic tidal, seismic and other effects if it hit the Earth – a possibility which has given rise to a disaster movie and studies of the possibility of using nuclear weapons to prevent the collision. In the early 1990s a US lobby for world preparations against such a disaster was active, although its real target may have been the unemployment and budget cuts faced by military scientists in need of new projects after the end of the Cold War.