Eratosthenian

lunar mare

lunar mare in the far north of the Moon

lunar mare

lunar impact crater

lunar mare

lunar crater

The Eratosthenian period in the lunar geologic timescale runs from 3.2 billion years ago to 1.1 billion years ago. It is named after the crater Eratosthenes, which displays characteristics typical of craters of this age, including a surface that is not significantly eroded by subsequent impacts, but which also does not possess a ray system. The massive basaltic volcanism of the Imbrian period tapered off and ceased during this long span of lunar time. The youngest lunar lava flows identified from orbital images are tentatively placed near the end of this period.

mountain on the Moon

Moon crater

lunar impact crater

lunar impact crater

lunar crater

lunar impact crater

lunar impact crater

lunar impact crater

lunar crater

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