Minor planet

A minor planet, according to the International Astronomical Union (IAU), is an astronomical object in direct orbit around the Sun that is exclusively classified as neither a planet nor a comet. Before 2006, the IAU officially used the term minor planet, but that year's meeting reclassified minor planets and comets into small Solar System bodies (SSSBs) and dwarf planets, including into the respective categories comets and Pluto, which were generally not considered minor planets. In contrast to the eight official planets of the Solar System, all minor planets fail to clear their orbital neighborhood. Minor planets include asteroids (near-Earth objects, Earth trojans, Mars trojans, Mars-crossers, main-belt asteroids and Jupiter trojans), as well as distant minor planets (Uranus trojans, Neptune trojans, centaurs and trans-Neptunian objects), most of which reside in the Kuiper belt and the scattered disc. As of June 2026, there are 1,544,016 known objects, divided into 895,910 numbered (secured discoveries) and 656,913 unnumbered minor planets. Approximately nine of the numbered minor planets are known or suspected to be dwarf planets. The first minor planet to be discovered was Ceres in 1801, though it was called a 'planet' at the time and an 'asteroid' soon after; the term minor planet was not introduced until 1841, and was considered a subcategory of 'planet' until 1932. The term planetoid has also been used, especially for larger, planetary objects such as those the IAU has called dwarf planets since 2006. Historically, the terms asteroid, minor planet, and planetoid have been more or less synonymous. This terminology has become more complicated by the discovery of numerous minor planets beyond the orbit of Jupiter, especially trans-Neptunian objects that are generally not considered asteroids. A minor planet seen releasing gas may be dually classified as a comet. Objects are called dwarf planets if their own gravity...