This prominent circular feature, known as the Richat Structure, in the Sahara desert of Mauritania is often noted by astronauts because it forms a conspicuous bull-eye on the otherwise rather featureless expanse of the desert.
This prominent circular feature, known as the Richat Structure, in the Sahara desert of Mauritania is often noted by astronauts because it forms a conspicuous bull-eye on the otherwise rather featureless expanse of the desert.