Minor-planet moon uncertain. There are 5 Jupiter trojans with a moon. Candidate binaries with an unconfirmed status are displayed on a dark background. There are only 2 centaurs with satellites, both of which are ring systems instead of moons. There are 87 trans-Neptunian objects known to have moons, with a total of 93 moons discovered. Candidate binaries with an unconfirmed status are displayed on a dark background. Minor-planet moon A minor-planet moon is an astronomical object that orbits a minor planet as its natural satellite. It is thought that many asteroids and Kuiper belt objects may possess moons, in some cases quite
Moons of Mars its 30-hour orbit, it takes 2.7 days to set in the west as it slowly falls behind the rotation of Mars. Both moons are tidally locked, always presenting the same face towards Mars. Since Phobos orbits Mars faster than the planet itself rotates, tidal forces are slowly but steadily decreasing its orbital radius. At some point in the future, when it approaches Mars closely enough (see Roche limit), Phobos will be broken up by these tidal forces. Several strings of craters on the Martian surface, inclined further from the equator the older they are, suggest that there may have been