Sahara Desert of Mauritania
/ February 19, 2013
In the Sahara desert of Mauritania, this prominent circular feature has attracted attention since the earliest space missions. Why? Because in the otherwise rather featureless expanse of the desert, it forms a conspicuous bull’s-eye.
The site was initially interpreted as a meteorite impact structure because of its high degree of circularity, but according to NASA, it is now thought to be "merely a symmetrical uplift that has been laid bare by erosion."
Image courtesy of NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team