Opportunity on Endeavour's rim
Opportunity is not at the edge of Odyssey's rim -- that is a large boulder. Opportunity blends a little better with the dusty ground, and is a small spot slightly more than one crater diameter to the right of Odyssey.
Opportunity travelled nearly three years to reach this rim because it contains rocks even more ancient than the rocks of Meridiani Planum, which the rover has been exploring since 2004, and hence may teach us something about an even more ancient era in Martian history.
Original image data dated on or about September 10, 2011.
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