Minor planet

A minor planet is an astronomical object in direct orbit around the Sun (or more broadly, any star with a planetary system) that is neither a planet nor exclusively classified as a comet. Before 2006 the International Astronomical Union (IAU) officially used the term minor planet, but during that year's meeting it reclassified minor planets and comets into dwarf planets and small Solar System bodies (SSSBs).Solar System → Local Interstellar Cloud → Local Bubble → Gould Belt → Orion Arm → Milky Way → Milky Way subgroup → Local Group → Local Sheet → Virgo Supercluster → Laniakea Supercluster → Observable universe → UniverseEach arrow (→) may be read as 'within' or 'part of'. A minor planet is an astronomical object in direct orbit around the Sun (or more broadly, any star with a planetary system) that is neither a planet nor exclusively classified as a comet. Before 2006 the International Astronomical Union (IAU) officially used the term minor planet, but during that year's meeting it reclassified minor planets and comets into dwarf planets and small Solar System bodies (SSSBs). Minor planets can be dwarf planets, asteroids, trojans, centaurs, Kuiper belt objects, and other trans-Neptunian objects. As of 2019, the orbits of 794,832 minor planets were archived at the Minor Planet Center, 541,128 of which had received permanent numbers (for the complete list, see index). The first minor planet to be discovered was Ceres in 1801. The term minor planet has been used since the 19th century to describe these objects. The term planetoid has also been used, especially for larger (planetary) objects such as those the International Astronomical Union (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 is sufficient to achieve hydrostatic equilibrium and form an ellipsoidal shape. All other minor planets and comets are called small Solar System bodies. The IAU stated that the term minor planet may still be used, but the term small Solar System body will be preferred. However, for purposes of numbering and naming, the traditional distinction between minor planet and comet is still used. Hundreds of thousands of minor planets have been discovered within the Solar System and thousands more are discovered each month. The Minor Planet Center has documented over 213 million observations and 794,832 minor planets, of which 541,128 have orbits known well enough to be assigned permanent official numbers. Of these, 21,922 have official names. As of 19 May 2019, the lowest-numbered unnamed minor planet is (3708) 1974 FV1, and the highest-numbered named minor planet is 518523 Bryanshumaker.