The Richat Structure: The Eye of the Earth

Spectacular formation remains a puzzle
The Richat Structure, Oudane, Mauritania, is not really a structure but a huge circular formation (50 km in diameter - 30 miles), that resembles an eye when looked upon from space. Originally thought to be a crater, this volcanic dome is most likely a product of erosion, an ancient geological artifact in the middle of featureless Maur Adrar desert, in Africa's Western Sahara. The earliest space missions used it as a landmark, the adventurous 4x4 enthusiasts consider it to be their playground, and scientists are still debating its origin.

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