• 300km radius asteroid orbiting between 8.5 and 18.9AU from the Sun, from just within the orbit of Saturn to that of Uranus. This orbit is considered unstable and Chiron’s future may involve either collision with a planet or gravitational ejection from the solar system. Asteroid 2060 in official nomenclature, Chiron is a member of the Kuiper belt and is one of a group of four known ‘Centaurs’, small bodies beyond Saturn, which must be representatives of a far larger population. Despite its designation, Chiron is in fact a massive comet nucleus about 150km across, not an asteroid, and displays a coma.