As MESSENGER sped by Mercury on January 14, 2008, the Narrow Angle Camera, (NAC), of the Mercury Dual Imaging System, (MDIS), captured this image, which includes the edge of the planet against the blackness of space. Much of the foreground shows a portion of Caloris basin, one of the largest impact basins in the solar system. The large crater in the bottom middle of this image has a diameter of about 70 kilometers, (40 miles). Caloris basin is an area of particular interest to the MESSENGER science team, since understanding its formation can lead to insights about the nature of large impacts in the early solar system and the results of these catastrophic events. The two large craters are each surrounded by a 'halo' of dark material. The smaller of the two craters has an unusual pattern of bright, highly reflective material on its floor. The fact that both of these craters, which show different material characteristics, are located within Caloris basin provides information about the variety and complexity of processes that have shaped Mercury's surface.