Mars Index - Top Ten MER Images - Top Raw Images
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In this mosaic of microscopic images, a 5-centimeter-wide (2-inch-wide) circular depression surrounded by fine clumps of dust exposes a smooth, dark surface interspersed with light-colored specks. From the top left to the bottom right is a thin, jagged crack filled with light-colored material.
Circles of Success
Concentric circles of repeated grinding show off the rover's handiwork.

Image Credit: NASA/JPL/Cornell/USGS