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The Moon is receding, but not at a constant rate forever

Lunar laser ranging shows that the Moon’s average distance from Earth is currently increasing by about 3.8 cm per year. The cause is tidal interaction: Earth’s tides transfer some angular momentum in the system to the Moon’s orbit.

Illustration is AI-generated and conceptual; scale is not preserved.

Over time the Moon will appear smaller in the sky, and an era will arrive when it can no longer fully cover the Sun. NASA estimates this will be more than about 600 million years from now. This is an approximate outlook, not a precise forecast from linearly extending today’s 3.8 cm/year: tidal evolution changes over time. Partial and annular eclipses will remain possible.