Mars Rover Opportunity does a self portrait on Sept. 11. Image credit: NASA/JPL-Caltech/Cornell University

The Mars Exploration Rover Opportunity took this self portrait on September 11, 2011 while exploring in the region of Endeavour crater called Cape York.

As of September 7, 2011 solar array energy production was 336 watt-hours, so it’s still pretty good.  The rover has traveled 20.86 miles on Mars so far.

The image is significant not because the ground it’s on, but that little American flag.  That flag is mounted on a piece of metal taken from the Twin Towers.  Sort of Oppy’s tribute.