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SpaceSurprise 4/5Difficulty 3/5Reviewed on September 13, 2026

The Moon is moving away from Earth by about 3.8 centimetres per year.

Why it is true

The gravitational interaction between Earth and the Moon transfers angular momentum to the lunar orbit. Measurements with retroreflectors left by the Apollo missions confirm that the distance increases by a few centimetres per year.

Source: NASA

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