Animation of the asteroids 951 Gaspra, 21 Lutetia and 243 Ida, which have all been visited by spacecraft. 951 Gaspra (left) became the first asteroid visited by a space probe, when Galileo passed in on its way to Jupiter, on 29th October 1991. It orbits on the inner edge of the Asteroid Belt, and measures some 18x10x9 kilometres in size. Galileo also passed 243 Ida (right), on 28th August 1993. It orbits in the main Asteroid Belt, and is 60x25x19km in size. 21 Lutetia was visited by the Rosetta spacecraft in July 2012. It is 121x101x75km in size. The asteroids are not associated in the Solar System, and are shown together for display purposes.