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37-550: As minor planet discoveries are confirmed, they are given a permanent number by the IAU 's Minor Planet Center (MPC), and the discoverers can then submit names for them, following the IAU's naming conventions . The list below concerns those minor planets in the specified number-range that have received names, and explains the meanings of those names. Official naming citations of newly named small Solar System bodies are approved and published in

74-463: 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

111-446: A Data Base of Physical and Dynamical Properties of Near Earth Asteroids. Environmental characteristics have three aspects: space environment, surface environment and internal environment, including geological, optical, thermal and radiological environmental properties, etc., which are the basis for understanding the basic properties of minor planets, carrying out scientific research, and are also an important reference basis for designing

148-568: A bulletin by IAU's Working Group for Small Bodies Nomenclature (WGSBN). Before May 2021, citations were published in MPC's Minor Planet Circulars for many decades. Recent citations can also be found on the JPL Small-Body Database (SBDB). Until his death in 2016, German astronomer Lutz D. Schmadel compiled these citations into the Dictionary of Minor Planet Names (DMP) and regularly updated

185-460: A false positive or become lost later on —called a provisionally designated minor planet . After the observation arc is accurate enough to predict its future location, a minor planet is formally designated and receives a number. It is then a numbered minor planet . Finally, in the third step, it may be named by its discoverers. However, only a small fraction of all minor planets have been named. The vast majority are either numbered or have still only

222-555: A name (e.g. 433 Eros ). The formal naming convention uses parentheses around the number, but dropping the parentheses is quite common. Informally, it is common to drop the number altogether or to drop it after the first mention when a name is repeated in running text. Minor planets that have been given a number but not a name keep their provisional designation, e.g. (29075) 1950 DA . Because modern discovery techniques are finding vast numbers of new asteroids, they are increasingly being left unnamed. The earliest discovered to be left unnamed

259-427: A provisional designation. Example of the naming process: A newly discovered minor planet is given a provisional designation . For example, the provisional designation 2002 AT 4 consists of the year of discovery (2002) and an alphanumeric code indicating the half-month of discovery and the sequence within that half-month. Once an asteroid's orbit has been confirmed, it is given a number, and later may also be given

296-556: A risk of impacting Earth in the few weeks following their discovery (see Potentially hazardous objects and § Videos ) . The Minor Planet Center was set up at the University of Cincinnati in 1947, under the direction of Paul Herget . Upon Herget's retirement on June 30, 1978, the MPC was moved to the Smithsonian Astrophysical Observatory, under the direction of Brian G. Marsden . From 2006 to 2015,

333-648: A somewhat larger surface soil layer size. Soil layers are inevitably subject to intense space weathering that alters their physical and chemical properties due to direct exposure to the surrounding space environment. In silicate-rich soils, the outer layers of Fe are reduced to nano-phase Fe (np-Fe), which is the main product of space weathering . For some small planets, their surfaces are more exposed as boulders of varying sizes, up to 100 metres in diameter, due to their weaker gravitational pull. These boulders are of high scientific interest, as they may be either deeply buried material excavated by impact action or fragments of

370-433: A variety of other rich geological effects on the surface of minor planets, such as mass wasting on slopes and impact crater walls, large-scale linear features associated with graben , and electrostatic transport of dust. By analysing the various geological processes on the surface of minor planets, it is possible to learn about the possible internal activity at this stage and some of the key evolutionary information about

407-480: Is condemned. The WGSBN publishes a comprehensive guideline for the naming rules of non-cometary small Solar System bodies. Minor planet 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

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444-506: Is similar to that of carbon- or iron-bearing meteorites, the interaction between the minor planets and the solar wind is likely to be unipolar induction , resulting in an external magnetic field for the minor planet. In addition, the magnetic fields of minor planets are not static; impact events, weathering in space and changes in the thermal environment can alter the existing magnetic fields of minor planets. At present, there are not many direct observations of minor planet magnetic fields, and

481-579: Is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory . The Minor Planet Center is the official worldwide organization in charge of collecting observational data for minor planets (such as asteroids ), calculating their orbits and publishing this information via

518-622: The Minor Planet Circulars . Under the auspices of the International Astronomical Union (IAU), it operates at the Smithsonian Astrophysical Observatory , which is part of the Center for Astrophysics along with the Harvard College Observatory . The MPC runs a number of free online services for observers to assist them in observing minor planets and comets. The complete catalogue of minor planet orbits (sometimes referred to as

555-721: The International Astronomical Union is dedicated to the Physical Study of Comets & Minor Planets. Archival data on the physical properties of comets and minor planets are found in the PDS Asteroid/Dust Archive. This includes standard asteroid physical characteristics such as the properties of binary systems, occultation timings and diameters, masses, densities, rotation periods, surface temperatures, albedoes, spin vectors, taxonomy, and absolute magnitudes and slopes. In addition, European Asteroid Research Node (E.A.R.N.), an association of asteroid research groups, maintains

592-450: The Kuiper belt and the scattered disc . As of October 2024 , there are 1,392,085 known objects, divided into 740,000 numbered , with only one of them recognized as a dwarf planet (secured discoveries) and 652,085 unnumbered minor planets, with only five of those officially recognized as a dwarf planet . The first minor planet to be discovered was Ceres in 1801, though it was called

629-503: The "Minor Planet Catalogue") may also be freely downloaded. In addition to astrometric data, the MPC collects light curve photometry of minor planets. A key function of the MPC is helping observers coordinate follow up observations of possible near-Earth objects (NEOs) via its NEO web form and blog, the Near-Earth Object Confirmation Page . The MPC is also responsible for identifying, and alerting to, new NEOs with

666-792: The MPC. The MPC periodically releases astrometric observations of minor planets, as well as of comets and natural satellites . These publications are the Minor Planet Circulars (MPCs), the Minor Planet Electronic Circulars (MPECs), and the Minor Planet Supplements (MPSs and MPOs). An extensive archive of publications in a PDF format is available at the Minor Planet Center's website. The archive's oldest publication dates back to 1 November 1977 (MPC 4937–5016). The Natural Satellites Ephemeris Service

703-471: The collection. Based on Paul Herget 's The Names of the Minor Planets , Schmadel also researched the unclear origin of numerous asteroids, most of which had been named prior to World War II. [REDACTED] This article incorporates text from this source, which is in the public domain : SBDB New namings may only be added to this list below after official publication as the preannouncement of names

740-506: The convection of the conductive fluid will generate a large and strong magnetic field . However, the size of a minor planet is generally small and most of the minor planets have a "crushed stone pile" structure, and there is basically no "dynamo" structure inside, so it will not generate a self-generated dipole magnetic field like the Earth. But some minor planets do have magnetic fields—on the one hand, some minor planets have remanent magnetism : if

777-459: The director of the MPC was Timothy Spahr , who oversaw a staff of five. From 2015 to 2021, the Minor Planet Center was headed by interim director Matthew Holman . Under his leadership, the MPC experienced a significant period of reorganization and growth, doubling both its staff size and the volume of observations processed per year. Upon Holman's resignation on February 9, 2021 (announced on February 19, 2021) Matthew Payne became acting director of

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814-458: 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

851-399: The fact that most minor planets are rubble pile structures, which are loose and porous, gives the impact action on the surface of minor planets its unique characteristics. On highly porous minor planets, small impact events produce spatter blankets similar to common impact events: whereas large impact events are dominated by compaction and spatter blankets are difficult to form, and the longer

888-697: The few existing planets detection projects generally carry magnetometers, with some targets such as Gaspra and Braille measured to have strong magnetic fields nearby, while others such as Lutetia have no magnetic field. Solar System   → Local Interstellar Cloud   → Local Bubble   → Gould Belt   → Orion Arm   → Milky Way   → Milky Way subgroup   → Local Group → Local Sheet → Virgo Supercluster → Laniakea Supercluster   → Local Hole   → Observable universe   → Universe Each arrow ( → ) may be read as "within" or "part of". Minor Planet Center The Minor Planet Center ( MPC )

925-469: The long-term interaction with the external environment, which may lead to some indication of the nature of the parent body's origin. Many of the larger planets are often covered by a layer of soil ( regolith ) of unknown thickness. Compared to other atmosphere-free bodies in the solar system (e.g. the Moon ), minor planets have weaker gravity fields and are less capable of retaining fine-grained material, resulting in

962-486: The lowest-numbered unnamed minor planet is (4596) 1981 QB , and the highest-numbered named minor planet is 594913 ꞌAylóꞌchaxnim . There are various broad minor-planet populations: All astronomical bodies in the Solar System need a distinct designation. The naming of minor planets runs through a three-step process. First, a provisional designation is given upon discovery—because the object still may turn out to be

999-420: The minor planet exploration mission, measuring the albedo and color changes of the planet surface is also the most basic method to directly know the difference in the material composition of the planet surface. The geological environment on the surface of minor planets is similar to that of other unprotected celestial bodies, with the most widespread geomorphological feature present being impact craters: however,

1036-462: The parent body had a magnetic field or if the nearby planetary body has a strong magnetic field, the rocks on the parent body will be magnetised during the cooling process and the planet formed by the fission of the parent body will still retain remanence, which can also be detected in extraterrestrial meteorites from the minor planets; on the other hand, if the minor planets are composed of electrically conductive material and their internal conductivity

1073-428: The payload of exploration missions Without the protection of an atmosphere and its own strong magnetic field, the minor planet's surface is directly exposed to the surrounding radiation environment. In the cosmic space where minor planets are located, the radiation on the surface of the planets can be divided into two categories according to their sources: one comes from the sun, including electromagnetic radiation from

1110-444: The periodic change of the planet's light curve, which can be observed by ground-based equipment, so as to obtain the planet's magnitude , rotation period , rotation axis orientation, shape, albedo distribution, and scattering properties. Generally speaking, the albedo of minor planets is usually low, and the overall statistical distribution is bimodal, corresponding to C-type (average 0.035) and S-type (average 0.15) minor planets. In

1147-399: The planet's parent body that have survived. The rocks provide more direct and primitive information about the material inside the minor planet and the nature of its parent body than the soil layer, and the different colours and forms of the rocks indicate different sources of material on the surface of the minor planet or different evolutionary processes. Usually in the interior of the planet,

Meanings of minor-planet names: 17001–18000 - Misplaced Pages Continue

1184-564: The planets receive such large impacts, the greater the overall density. In addition, statistical analysis of impact craters is an important means of obtaining information on the age of a planet surface. Although the Crater Size-Frequency Distribution (CSFD) method of dating commonly used on minor planet surfaces does not allow absolute ages to be obtained, it can be used to determine the relative ages of different geological bodies for comparison. In addition to impact, there are

1221-487: The publication of the Minor Planet Circular (MPC) of October 19, 2005, which saw the highest-numbered minor planet jump from 99947 to 118161. The first few asteroids were named after figures from Greek and Roman mythology , but as such names started to dwindle the names of famous people, literary characters, discoverers' spouses, children, colleagues, and even television characters were used. Commission 15 of

1258-400: The sun, and ionizing radiation from the solar wind and solar energy particles; the other comes from the sun outside the solar system, that is, galactic cosmic rays , etc. Usually during one rotation period of a minor planet, the albedo of a minor planet will change slightly due to its irregular shape and uneven distribution of material composition. This small change will be reflected in

1295-619: 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 8 November 2021 ,

1332-461: Was finally named 15760 Albion in January 2018. A few objects are cross-listed as both comets and asteroids, such as 4015 Wilson–Harrington , which is also listed as 107P/Wilson–Harrington . Minor planets are awarded an official number once their orbits are confirmed. With the increasing rapidity of discovery, these are now six-figure numbers. The switch from five figures to six figures arrived with

1369-517: Was for a long time (3360) 1981 VA , now 3360 Syrinx . In November 2006 its position as the lowest-numbered unnamed asteroid passed to (3708) 1974 FV 1 (now 3708 Socus ), and in May 2021 to (4596) 1981 QB . On rare occasions, a small object's provisional designation may become used as a name in itself: the then-unnamed (15760) 1992 QB 1 gave its "name" to a group of objects that became known as classical Kuiper belt objects ("cubewanos") before it

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