NASA's Mars Exploration Rover Opportunity used its navigation camera to take the exposures combined into this view of a 30 foot (9 meters) crater, informally named "Skylab," along the rover's route. The component images were taken during the 2,594th martian day, or sol, of the rover's work on Mars (May 12, 2011). The blocks of material ejected from the crater-digging impact sit on top of the sand ripples near the crater. This suggests, from the estimated age of the area's sand ripples, that the crater was formed within the past 100,000 years. The dark sand inside the crater attests to the mobility of fine sand in the recent era in this Meridiani Planum region of Mars.