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The locking of the rotation of a body to its revolution around another body through gravitational forcing. (also known as spin orbit lock)
The lunar lowlands filled by successive flows of dark lava; from the Latin word for sea. (singular "mare").
A narrow, winding valley on the moon caused by ancient lava flows along narrow channels.
Meteorite of microscopic size. These meteorites are especially important for airless worlds as they produce regolith (ex: the moon).
The age of a geological feature referred to other features. For example, relative ages reveal that the lunar maria are younger than the highlands.
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