In astronomy, a regular moon is a natural satellite following a relatively close and prograde orbit with little orbital inclination or eccentricity. They are believed to have formed in orbit about their primary, as opposed to irregular moons, which were captured.

The eight planets of the Solar System host at least 57 regular satellites combined: one around Earth, eight around Jupiter, 23 named regular ones around Saturn (not counting hundreds or thousands of moonlets), 18 known ones around Uranus, and 7 small regular ones around Neptune. (Neptune's largest moon, Triton, appears to have been captured.) It is thought that Pluto's five moons and Haumea's two were formed in orbit about those dwarf planets out of debris created in giant collisions.

Most regular moons are known to be tidally locked to their parent planet; the one known exception is Saturn's Hyperion, which exhibits chaotic rotation.

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