Sigma 7

        This mosaic was acquired by the Mars Exploration Rover Opportunity on Sol 2585 (May 2, 2011). Sigma 7 was a NASA Project Mercury spacecraft in which Walter Schirra in 1962 achieved six Earth orbits. The larger sandy crater in the center of the mosaic is named Sigma 7 and is approximately 5 meters in diameter. The crater named Freedom 7 with exposed outcrop can be seen beyond Sigma 7 in the upper right of the mosaic. The other craters are unnamed.  Pancam's 753 nm, 535 nm, and 432 nm filters were used in this mosaic.  Two versions are available below at full resolution: an approximate true color rendering, and a false color stretch to enhance the subtle color differences in the scene.

Jim Bell
Pancam Instrument Lead
June 16, 2011