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
Definition of planet to 400 astronomical units from the star. A Mars-mass body at the orbit of Pluto clears its orbit. This metric, which leaves Pluto as a dwarf planet, applies to both the Solar System and to extrasolar systems. Some opponents of the definition have claimed that "clearing the neighbourhood" is an ambiguous concept. Mark Sykes, director of the Planetary Science Institute in Tucson, Arizona, and organiser of the petition, expressed this opinion to National Public Radio. He believes that the definition does not categorise a planet by composition or formation, but, effectively, by its location. He believes that a Mars-sized or