What on Earth is that? The Richat Structure in the Sahara Desert
of Mauritania is easily visible from space because it is nearly
50 kilometers across. Once thought to be an impact crater, the
flat middle and lack of shock-altered rock indicates otherwise.
The possibility that the Richat Structure was formed by a also
seems improbable because of the lack of a dome of igneous or
volcanic rock. Rather, the layered of the Richat structure is
now thought by many to have been caused by uplifted rock
sculpted by The above image was captured by the onboard the
orbiting orbiting Why the Richat Structure is nearly circular
remains a mystery.