NASA's Mars Exploration Rover Opportunity used its panoramic camera to capture this raw image looking across Endeavour crater during the rover's 2,686th Martian day, or sol, of work on Mars (August 14, 2011).
Opportunity had arrived at the western rim of 13-mile-diameter (21-kilometer-diameter) Endeavour crater five days earlier. The distant horizon in this image is a portion of the east-northeastern rim of Endeavour. The large rock on the left in the foreground, informally named "Tisdale 1," is about 30 inches (about 80 centimeters) tall. It is part of a group of rocks that appear to have been ejected by the excavation of Odyssey crater on the rim of Endeavour crater.
Photo credit: NASA/JPL-Caltech/Cornell/Arizona State University