This circular formation is likely a collapse pit or an impact crater.
NASA/JPL-Caltech/Univ. of ArizonaIt looks like something you wouldn't want to fall into.
NASA's Mar Reconnaissance Orbiter peered down and caught sight of an unusual-looking pit formation in the region of the Red Planet's South Pole. It's late summer there, the sun is low and NASA notes, "subtle topography is accentuated in orbital images."
The space agency refers to the patterns created by carbon dioxide ice as "Swiss cheese terrain." The deep round formation is most likely a collapse pit -- a depression often caused by the ground sinking into a void below -- or an impact crater.
This isn't the first time NASA scientists have eyed a weird formation on Mars and asked, "Is that an impact crater?" An MRO image released in April shows a scaly-looking indentation, also located at the planet's South Pole area.
NASA released the pit image on Friday as another spectacular reminder of just how weird, wonderful and mysterious Mars can be.
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