Mare Cognitum

lunar basin

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June 30, 2026

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Mare Cognitum is a lunar basin on the Moon, a large, dark plain visible from Earth. The term "mare" (Latin for "sea") was historically used by astronomers like Galileo to describe these dark areas, though they are actually ancient basins filled with congealed lava flows, not water. These basins, formed by large impacts billions of years ago, are often associated with mascons, regions of excess gravitational attraction due to dense magma upwelling from the Moon's interior. Mare Cognitum is one of these prominent features that contribute to the patterns seen as the "man in the Moon".123

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Moon
First robotic missions
…of Ranger 7 was named Mare Cognitum for the new knowledge gained, a major example of which was the discovery that even small lunar features have been mostly subdued from incessant meteorite impacts.
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…of Ranger 7 was named Mare Cognitum for the new knowledge gained, a major example of which was the discovery that even small lunar features have been mostly subdued from incessant meteorite impacts.
Read More