Three craters stretch across the Meridiani Planum region of Mars. The nearest is an old crater, almost worn away. It is 34 kilometres across. The second is covered in dark material, most likely a substance resembling volcanic ash. It is 50 kilometres wide. The third crater, more distant, is smaller at 15 kilometres wide. This crater too, has a dark floor, perhaps because material from the largest crater has been blown out in by the wind.
Credits: ESA/DLR/FU Berlin (G. Neukum).