Animation of the asteroid 243 Ida. This is a main-belt asteroid, orbiting the Sun between the orbits of Mars and Jupiter. It is a member of the Koronis family of asteroids, thought to be fragments of a larger body destroyed in a collision some two billion years ago. Ida has an irregular shape, being some 54x24x15 kilometres in size. Ida was discovered in 1884, and was visited by the Galileo spacecraft on its way to Jupiter in 1993.