In astronomy, what term is given to a miniature moon?

A moonlet, minor moon, minor natural satellite, or minor satellite is a particularly small natural satellite orbiting a planet, dwarf planet, or other minor planet.

Up until 1995, moonlets were only hypothetical components of Saturn's F-ring structure, when the Earth passed through Saturn's ring plane. The Hubble Space Telescope and the European Southern Observatory both captured objects orbiting close or near the F-ring. In 2004, Cassini caught an object 4-5km in diameter on the outer ring of the F-ring and then 5 hours later on the inner F-ring, showing that the object had orbited.

Three different types of small moons have been called moonlets:

A belt of objects embedded in a planetary ring, especially around Saturn, such as those in the A Ring, S/2009 S 1 in the B Ring ("propeller" moonlets), and those in the F Ring.

Occasionally asteroid moons, such as those of 87 Sylvia (8th-largest asteroid in the asteroid belt).

A subsatellite is a natural or artificial satellite that orbits a natural satellite, i.e. a "moon of a moon".