This impact crater in the Nilosyrtis region of Mars contains numerous layers exposed along its floor. These layers formed long after the impact event and are likely deposits of dust and ice.
Also present are dunes of dark sand that probably blew in from the surrounding terrain. (Image is less than 5 km [3 mi] across and is 299 km [186 mi] above the surface. For full images including scale bars, visit the source link.)
Larger image
www.uahirise.org/ESP_025001_2255
NASA/JPL/UArizona
