Scientists are investigating the ripples and textures seen in these images, taken by cameras on NASA's Mars Exploration Rover Opportunity from its position on the southeast side of the rim of "Endurance" Crater. The largest image was taken by the rover's navigation camera; the inset was taken by the panoramic camera; and the highlighted strip within the inset was taken by the microscopic imager on the rover's instrument deployment device, or "robotic arm." Scientists are hoping to determine more about the aqueous history that formed the sulfate outcrops seen in "Eagle" Crater, "Fram" Crater and on the rim of Endurance Crater.