Asteroid 243 Ida. Mosaic of five frames showing the asteroid 243 Ida. Ida is a stony S class asteroid about 52 kilometres in length. It is a member of the Koronis family, thought to have originated from a larger body which broke up. Its surface is extensively cratered, with many large old craters. This shows that the surface is relatively ancient. The frames which were used to make this image were gathered by the Galileo spacecraft on its way to Jupiter. The frames were photographed using a Solid-State Imaging System at a distance of 3057 km to 3821 km, giving a resolution of around 35 metres per pixel. The image was made on 28 August 1993.