The list of minor planets consists of more than 700 partial lists, each containing 1000 minor planets grouped into 10 tables. The data is sourced from the
Minor Planet Center (MPC) and expanded with data from the
JPL SBDB (mean-diameter), Johnston's archive (sub-classification) and others
(see detailed field descriptions below). For an overview of all existing partial lists,
see . The information given for a minor planet includes a
permanent and
provisional designation
(), a citation that links to the
meanings of minor planet names (only if named), the discovery date, location, and credited
discoverers ( and ), a category with a more refined classification than the principal grouping represented by the background color
(), a mean-diameter, sourced from JPL's
SBDB or otherwise calculated estimates in italics
(), and a reference (Ref) to the corresponding pages at MPC and JPL SBDB. The MPC may credit one or several astronomers, a
survey or similar program, or even the
observatory site with the discovery. In the first column of the table, an existing stand-alone article is linked in boldface, while (self-)redirects are never linked. Discoverers, discovery site and category are only linked if they differ from the preceding catalog entry.
Example The example above shows five catalog entries from
one of the partial lists. All five asteroids were discovered at
Palomar Observatory by the
Palomar–Leiden survey (PLS). The MPC directly credits the survey's principal investigators, that is, the astronomers
Cornelis van Houten,
Ingrid van Houten-Groeneveld and
Tom Gehrels. (This is the only instance where the list of minor planets diverges from the
Discovery Circumstances in the official MPC list.)
189004 Capys, discovered on 16 October 1977, is the only named minor planet among these five. Its background color indicates that it is a
Jupiter trojan (from the
Trojan camp at Jupiter's ), estimated to be approximately 12 kilometers in diameter. All other objects are smaller asteroids from the inner (white), central (light-grey) and outer regions (dark grey) of the
asteroid belt. The provisional designation for all objects is an uncommon
survey designation.
Designation After discovery, minor planets generally receive a
provisional designation, e.g. , then a leading sequential number in parentheses, e.g. , turning it into a permanent designation (numbered minor planet). Optionally, a name can be given, replacing the provisional part of the designation, e.g. . (On Wikipedia, named minor planets also drop their parentheses.) In modern times, a minor planet receives a sequential number only after it has been observed several times over at least 4 oppositions. Minor planets whose orbits are not (yet) precisely known are known by their provisional designation. This rule was not necessarily followed in earlier times, and some bodies received a number but subsequently became
lost minor planets. The 2000 recovery of , which had been lost for nearly 89 years, eliminated the last numbered lost asteroid. Only after a number is assigned is the minor planet eligible to receive a name. Usually the discoverer has up to 10 years to pick a name; many minor planets now remain unnamed. Especially towards the end of the twentieth century, large-scale automated asteroid discovery programs such as
LINEAR have increased the pace of discoveries so much that the vast majority of minor planets will most likely never receive names. For these reasons, the sequence of numbers only approximately matches the timeline of discovery. In extreme cases, such as lost minor planets, there may be a considerable mismatch: for instance the high-numbered was originally discovered in 1937, but it was lost until 2003. Only after it was rediscovered could its orbit be established and a number assigned.
Discoverers The MPC credits more than 1,000 professional and amateur astronomers as
discoverers of minor planets. Many of them have discovered only a few minor planets or even just co-discovered a single one. Moreover, a discoverer does not need to be a human being. There are about 300 programs, surveys and observatories
credited as discoverers. Among these, a small group of U.S. programs and surveys actually account for most of all discoveries made so far
(see pie chart). As the total of numbered minor planets is growing by the tens of thousands every year, all statistical figures are constantly changing. In contrast to the Top 10 discoverers displayed in this articles, the MPC summarizes the total of discoveries somewhat differently, that is by a distinct group of discoverers. For example, bodies discovered in the
Palomar–Leiden Survey are directly credited to the program's principal investigators.
Discovery site Observatories, telescopes and
surveys that report
astrometric observations of
small Solar System bodies to the Minor Planet Center receive a numeric or alphanumeric
MPC code such as
675 for the
Palomar Observatory, or
G96 for the
Mount Lemmon Survey. On numbering, the MPC may directly credit such an observatory or program as the discoverer of an object, rather than one or several astronomers.
Category In this catalog, minor planets are classified into one of 8 principal orbital groups and highlighted with a distinct color. These are: The vast majority of minor planets are evenly distributed between the inner-, central and outer parts of the
asteroid belt, which are separated by the two
Kirkwood gaps at 2.5 and 2.82
AU. Nearly 97.5% of all minor planets are main-belt asteroids (MBA), while
Jupiter trojans,
Mars-crossing and
near-Earth asteroids each account for less than 1% of the overall population. Only a small number of
distant minor planets, that is the
centaurs and
trans-Neptunian objects, have been numbered so far. In the partial lists, table column "category" further refines this principal grouping: • main-belt asteroids show their
family membership based on the synthetic
hierarchical clustering method by
Nesvorný (2014), •
resonant asteroids are displayed by their numerical ratio and include the
Hildas (3:2),
Thules (4:3) and
Griquas (2:1), while the Jupiter trojans (1:1) display whether they belong to the
Greek () or
Trojan camp (), •
Hungaria asteroids (H), are labelled in italics (
H), when they are not members of the collisional family • near-Earth objects are divided into the
Aten (ATE),
Amor (AMO),
Apollo (APO), and
Atira (IEO) group, with some of them being
potentially hazardous asteroids (PHA), and/or larger than one kilometer in diameter (
+1km) as determined by the MPC. • trans-Neptunian objects are divided into dynamical subgroups including
cubewanos (
hot or cold),
scattered disc objects,
plutinos and other
Neptunian resonances, •
comet-like and/or retrograde objects with a
TJupiter value below 2 are tagged with
damocloid, •
other unusual objects based on MPC's and Johnston's lists are labelled
unusual, •
binary and
trinary asteroids with companions are tagged with "moon" and link to their corresponding entry in
minor-planet moon, • objects with an exceptionally long or short
rotation period are tagged with "slow" (period of 100+ hours) or "fast" (period of less than 2.2 hours) and link to their corresponding entry in
List of slow rotators and
List of fast rotators, respectively. • minor planets which also received a periodic-comet number (such as ) link to the
List of numbered comets : (a) NEO-subgroups with number of members:
Aten (286),
Amor (1,641),
Apollo (1,966), and
Atira (13) asteroids. : (b) Including 14 unclassified bodies: (). : (c) This chart has been created using a classification scheme adopted from and with data provided by the
JPL Small-Body Database.
Diameter If available, a minor planet's
mean diameter in meters (m) or kilometers (km) is taken from the
NEOWISE mission of NASA's
Wide-field Infrared Survey Explorer, which the
Small-Body Database has also adopted. Mean diameters are rounded to two significant figures if smaller than 100 kilometers. , ~15.3% (135,623) of numbered minor plants have a known diameter. Estimates are in italics and calculated from a magnitude-to-diameter conversion, using an assumed
albedo derived from the body's orbital parameters or, if available, from a
family-specific mean albedo
(also see asteroid family table). == Main index ==