Vesta asteroid surface. Coloured composite image of the surface of the giant asteroid Vesta, showing the Antonia crater. This crater has a diameter of 17 kilometres. The light blue material is fine-grain material excavated from the lower crust. The southern edge of the crater was buried by coarser material shortly after the crater formed. The dark blue of the southern crater rim is due to shadowing of the blocky material. This image was created by assigning ratios of colour information collected from several colour filters in visible light and near-infrared light to maximise the subtle differences in lithology (the physical characteristics of rock units, such as colour, texture and composition). Image obtained by the framing camera on NASA's Dawn