List of minor planets

The list of minor planets contains hundreds of thousands numbered minor planets, including Pluto. For an overview, see § Main index.

Growing number of discovered minor planets since 1995.
This list includes all minor planets, that are:

•      numbered but unnamed
•      numbered and named

while unnumbered minor planets have no discoverers yet defined and are not part of this list (    ).

This is a list of numbered minor planets in the Solar System, in numerical order. As of July 2017 there are 496,815 numbered minor planets, and 237,441 unnumbered.^[1] Only 21,009 or approximately 4% of all numbered minor planets are currently named, mostly for people and figures from mythology and fiction.^[1] The Jupiter trojan (3708) 1974 FV1 is currently the lowest-numbered unnamed minor planet.^[2] Minor planets also include dwarf planets of which 5 have been officially recognized by the IAU with potentially hundreds more to follow in the future.

For specific lists on physical, orbital and other properties, as well as on discovery circumstances and other aspects, see § Specific minor planet lists

Partial lists

The list of minor planets consists of nearly 500 partial lists, each containing 1000 minor planets grouped in 10 tables. The data is sourced from the Minor Planet Center (MPC). For an overview of all existing partial lists, see § Main index.

Example

The example above shows the beginning of the first table in partial list 189,001 to 190,000. It has the columns § Designation showing its permanent (number and name) and provisional designation, § Discovery, giving the date and location of its discovery, and column § Discoverers, for people, surveys, programs and observatories that are officially credited with its discovery. In the column "category" an asteroid's membership to a family, group and/or camp is displayed. The catalog table also contains a reference column that externally links to the body's dedicated page at the Minor Planet Center's website and to the corresponding entry in meanings of minor planet names (latter for named minor planets only).

In this example, all 5 bodies were discovered at Palomar Observatory by a trio of astronomers: Cornelis van Houten, Ingrid van Houten-Groeneveld and Tom Gehrels. The row's color represents a minor planet's orbital group—cyan is used for Jupiter trojans, while a white, light-grey and dark-grey color is used for asteroids of the inner, middle and outer regions of the asteroid belt, respectively. For more information, see § Orbital groups. As only 189004 Capys has been named yet, the other four bodies only display their number in the permanent designation column. The provisional designation displayed in this example is an uncommon survey designation.

•   LINEAR: 147,523 (30.7%)
•   Spacewatch: 129,357 (26.9%)
•   Mt. Lemmon Surv.: 50,178 (10.4%)
•   NEAT: 40,942 (8.5%)
•   CSS: 25,370 (5.3%)
•   LONEOS: 21,872 (4.5%)
•   van Houtens + Gehrels: 4,625 (1.0%)
•   Eric Walter Elst: 3,867 (0.8%)
•   WISE: 2,978 (0.6%)
•   Siding Spring Surv.: 2,727 (0.6%)
•   All others: 51,367 (10.7%)

Top discoverers of minor planets (corrected MPC-figures),^[3] out of a total of 480,806 numbered bodies (slices are linked to articles)^[4]

Discoverers

The MPC credits more than 1000 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 thousands on a monthly basis, all statistical figures are constantly changing. Note that the MPC summarizes the total of discoveries somewhat differently (typically by distinct group of discoverers), for example, bodies discovered in the Palomar–Leiden Survey are directly credited to the trio of astronomers as displayed in the above table.

Designation

After discovery, minor planets generally receive a provisional designation, e.g. 1989 AC, then a leading sequential number in parenthesis, e.g. (4179) 1989 AC, turning it into a permanent designation (numbered minor planet). Optionally, a name can be given, replacing the provisional part of the designation, e.g. 4179 Toutatis. (Note that on Wikipedia, named minor planets also drop their parenthesis.)

In modern times, a minor planet receives a sequential number only after it has been observed several times over at least 4 oppositions.^[5] 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. In 2000, 719 Albert was the last numbered asteroids to be recovered after having been lost for nearly 89 years.^[6]

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 remain unnamed. Especially towards the end of the twentieth century, with large-scale automated asteroid discovery programs such as LINEAR, the pace of discoveries has increased so much that it seems likely that the vast majority of minor planets will never receive names.

For the reasons mentioned above, 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 69230 Hermes was originally discovered in 1937, but it was a lost until 2003. Only after it was rediscovered could its orbit be established and a number assigned.

Discovery

All observatories that officially are a site where minor planets are discovered have received a numeric or alphanumeric code such as 675 for the Palomar Observatory, or I41 for the Palomar Transient Factory, a dedicated survey that runs at Palomar Mountain.

Orbital groups

In the partial lists, numbered minor planets (MPs) are categorized into one of 8 distinct orbital groups. These are the near-Earth asteroids, the Mars-crossing asteroids, the inner-, middle- and outer main-belt asteroids (MBA), the Jupiter trojans, the centaurs and the trans-Neptunian objects. A minor planet's orbital group is represented by the background color of the table row (see § Example). This classification is exclusively based on the body's relevant orbital elements, that is, its semi-major axis (a) and eccentricity (e). From these elements its perihelion (q) and aphelion (Q) can be derived.^[4]

Colorized orbital group	MPs (#)	MPs (%)	Distribution	Orbital criteria
Near-Earth object(a)	2,471	0.50%		q < 1.3 AU
Mars-crosser	4,787	0.96%		1.3 AU < q < 1.666 AU; a < 3.2 AU
MBA (inner)	165,684	33.35%		a < 2.5 AU; q > 1.666 AU
MBA (middle)	173,618	34.95%		2.5 AU < a < 2.82 AU; q > 1.666 AU
MBA (outer)	145,085	29.20%		2.82 AU < a < 4.6 AU; q > 1.666 AU
Jupiter trojan	4,713	0.95%		4.6 AU < a < 5.5 AU; e < 0.3
Centaur	88	0.02%		5.5 AU < a < 30.1 AU
Trans-Neptunian object	348	0.07%		a > 30.1 AU
Total (numbered)	496,815(b)	100%		Source: JPL's SBDB[4]

^(a) NEOs can be further divided into Aten (208), Amor (1,011), Apollo (1,246) and Atira (6) asteroids

^(b) Including 21 unclassified bodies: 6144 Kondojiro, 8373 Stephengould, 9767 Midsomer Norton, (18916) 2000 OG₄₄, (32511) 2001 NX₁₇, (96177) 1984 BC, (115916) 2003 WB₈, (119047) 2001 HM₁₂, (136620) 1994 JC, (144870) 2004 MA₈, (241944) 2002 CU₁₄₇, (275618) 2000 AU₂₄₂, (301964) 2000 EJ₃₇, (306418) 1998 KK₅₆, (322713) 2000 KD₄₁, (363135) 2001 QQ₁₉₉, (405058) 2001 TX₁₆, (477587) 2010 JT₈₆, (487496) 2014 SE₂₈₈, (490171) 2008 UD₂₅₃, (494667) 2001 WX₁ (colored as   for being unclassified).

The vast majority of numbered minor planets are from the asteroid belt. Approximately 97.5% are evenly distributed between the inner-, middle and outer asteroid belt, which are separated by the two Kirkwood gaps at 2.5 and 2.82 AU. They are followed by the Jupiter trojans, Mars-crossers and near-Earth asteroids, which account for less than 1% of the overall population each. Only a small number of centaurs and trans-Neptunian objects have been numbered so far.

With the exception of using 2.5–2.82 AU for main belt asteroids of the middle region, and adding the orbital criteria of q > 1.666 AU for outer MBAs, the above table agrees with the definitions given at JPL's SBDB. There are a few minor planets that remain unclassified based on the defined orbital criteria. Five of these bodies have a semi-major axis too large to be an outer main-belt asteroid, and an orbit too eccentric to be classified as a Jupiter trojan (JPL classifies these bodies simply as "asteroids", while the MPC, which never distinguishes between inner, outer and middle MBAs, classifies them as "main-belt asteroids"). The others are Mars-crossers (as per MPC) with (mostly) a semi-major axis of that of an outer-MBA (as per JPL).

Main index

This is an overview of all existing partial lists of numbered minor planets. Each table stands for 100,000 minor planets, each cell for a specific partial list of 1,000 sequentially numbered bodies. For an introduction, see § top

Numberings 1–100,000

Numberings 100,001–200,000

Numberings 200,001–300,000

Numberings 300,001–400,000

Numberings 400,001–500,000

Specific minor planet lists

Euler diagram showing the types of bodies in the Solar System (see Small Solar System body).

The following are lists of minor planets by physical properties, orbital properties, or discovery circumstances: selves into a sphere.

• List of exceptional asteroids (physical properties)
  • List of slow rotators (minor planets)
  • List of fast rotators (minor planets)
• List of instrument-resolved minor planets
• List of Jupiter trojans (Greek camp)
• List of Jupiter trojans (Trojan camp)
• List of minor planets visited by spacecraft
• List of minor planet moons
• List of minor-planet groups
• List of named minor planets (alphabetical)
• List of named minor planets (numerical)
• List of exceptional asteroids
• List of possible dwarf planets
• List of trans-Neptunian objects
• List of unnumbered minor planets (about 32% of minor planets as of July 2017)
• Meanings of minor planet names
  • List of minor planets named after people
  • List of minor planets named after places
  • List of minor planets named after rivers
  • List of minor planets named after animals and plants

See also

• Binary asteroid
• Dwarf planets – Pluto, Ceres, Eris, Haumea, and Makemake
• Kuiper belt
• Minor-planet moon
• Trans-Neptunian object

Other lists

• List of comets
• Planet § Objects formerly considered planets

References

Further reading

• Dictionary of Minor Planet Names, 5th ed.: Prepared on Behalf of Commission 20 Under the Auspices of the International Astronomical Union, Lutz D. Schmadel, ISBN 3-540-00238-3
• The Names of the Minor Planets, Paul Herget, 1968, OCLC 224288991

External links

• NASA Near Earth Object Program
• PDS Asteroid Data Archive
• SBN Small Bodies Data Archive
• JPL Minor Planet Database for physical and orbital data (of any Small Solar System Body or dwarf planet)
• Scott Manley's timelapse animation of Asteroid Discovery 1980–2012 on YouTube (min. 3:13)

Minor Planet Center

• Lists and plots: Minor Planets
• MPC Discovery Circumstances (minor planets by number)
• List of the Potentially Hazardous Asteroids (PHAs)
• Asteroid Hazards, Part 1: What Makes an Asteroid a Hazard? on YouTube (min. 6:04)
• Asteroid Hazards, Part 2: The Challenge of Detection on YouTube (min. 7:14)
• Asteroid Hazards, Part 3: Finding the Path on YouTube (min. 5:38)