The surface of Mercury is revealed in this scene imaged by MESSENGER's Narrow Angle Camera (NAC) on the Mercury Dual Imaging System (MDIS) during the spacecraft's flyby on January 14, 2008. Resolution is about 250 meters per pixel (about 820 feet/pixel). For this image, the Sun is illuminating the scene from the top and north is to the left. The outer diameter of the large double ring crater at the center of the scene is about 260 km (about 160 miles). The crater appears to be filled with smooth plains material that may be volcanic in nature. Multiple chains of smaller secondary craters are also seen extending radially outward from the double ring crater. Double or multiple rings form in craters with very large diameters, often referred to as impact basins.