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Luni-solar tidal friction pushes the Moon outward by roughly four centimetres each year. The figure is taken from NASA Science, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

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The Moon is slowly drifting away from Earth

Luni-solar tidal friction pushes the Moon outward by roughly four centimetres each year

The Moon moves about 3.8 centimetres further away from Earth every year. Gravitational pulls between Earth's oceans and the Moon create tidal bulges that drag against planetary rotation, gradually transferring energy to the lunar orbit and pushing it into a wider path.

Full moon partially obscured by atmosphere — NASA · Public domain · source

Where this comes from

NASA Science

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Tags: moon, orbit, tides

The Moon is slowly drifting away from Earth: the short answers

Where does this come from, and can I check it?: Luni-solar tidal friction pushes the Moon outward by roughly four centimetres each year. The figure is taken from NASA Science, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a space fact?: Yes. It sits on the Space shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.