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a large round pit caused by the impact of a meteoroid on the moon's surface


large, dark, flat areas on the moon


mountains on the moon


the movement of an object around another object


a single complete turn (axial or orbital)


(astronomy) the particular appearance of a body's state of illumination (especially one of the recurring shapes of the part of Earth's moon that is illuminated by the sun)

lunar cycle

the continuous waxing and waning phases of the moon

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