Mysterious Martian Spheres

This NASA image shows small spherical objects captured by the Microscopic Imager on Mars Rover Opportunity and covers an area only about 2.4 inches across, so the individual spheres are up to about one-eighth of an inch (3 millimetres) in diameter.   Image credit: NASA/JPL-Caltech/Cornell Univ./ USGS/Modesto Junior College/AFP/GettyImages

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Opportunity was in an outcrop called “Kirkwood” in the Cape York segment of the western rim of Endeavour Crater.

Opportunity finds Mysterious Martian Spheres

Image credit Wikimedia

via NASA