In 1965, astronauts James McDivitt and Ed White spotted a massive circular crater-like structure in the middle of the Sahara Desert. Called the “Eye of the Sahara”, the Richat Structure is now known to not be a crater, but a geological pimple. It is theorised to have been molten rock that never fully erupted on the surface that had also collapsed in on itself due to the dissolution of the limestone around its centre.
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