List of exceptional asteroids


The following is a collection of lists of exceptional asteroids in the Solar System. For the purposes of this article "asteroid" means minor planet up to the orbit of Neptune, which includes the likely dwarf planet Ceres, the Jupiter trojans and the centaurs. For a complete list of minor planets in numerical order, see List of minor planets.
Asteroids are given minor planet numbers, but not all minor planets are asteroids. Minor planet numbers are also given to objects of the Kuiper belt, which is similar to the asteroid belt but farther out around 30–60 AU, whereas asteroids are mostly between 2–3 AU from the Sun and at the orbit of Jupiter 5 AU from the Sun. Also, comets are not typically included under minor planet numbers, and have their own naming conventions.
Asteroids are given a unique sequential identifying number once their orbit is precisely determined. Prior to this, they are known only by their systematic name or provisional designation, such as.

Physical characteristics

Largest by diameter

Estimating the sizes of asteroids from observations is difficult due to their irregular shapes, varying albedo, and small angular diameter. For example, pure C-type asteroids are much darker than most. Asteroids with only one or two axes measured may have a falsely inflated geometric mean diameter if the unknown second or third axis is significantly smaller than the primary axis. Asteroid 16 Psyche has an IRAS diameter of 253 km, yet has a more recent and accurate geometric mean of only 186 km.
The number of bodies grows rapidly as the size decreases. Based on IRAS data there are about 140 main-belt asteroids with a diameter greater than 120 km. For a more complete list, see List of Solar System objects by size.
The inner asteroid belt has few large asteroids. Of those in the above list, only 4 Vesta, 19 Fortuna, 6 Hebe, 7 Iris and 9 Metis orbit there.

Most massive

Below are the nineteen most massive measured asteroids. Ceres, at a third the estimated mass of the asteroid belt, is as massive as the next seventeen largest put together. The masses of asteroids are calculated from perturbations they induce on the orbits of other asteroids, except for asteroids that have been visited by spacecraft or have an observable moon, where a direct mass determination is possible. Different sets of astrometric observations lead to different mass determinations; the biggest problem is accounting for the aggregate perturbations caused by all of the smaller asteroids.
NameMass
PrecisionApprox.
proportion
of all
asteroids
1 Ceres938.350.001% 31%
4 Vesta259.0760.0004% 8.6%
2 Pallas2016.5% 6.7%
10 Hygiea83.29.6% 2.9%
704 Interamnia38.84.6% 1.3%
511 Davida37.75.2% 1.3%
532 Herculina3317% 1.1%
15 Eunomia31.80.9% 1.1%
3 Juno28.616% 0.95%
16 Psyche22.7
24.1 		3.7%
13% 		0.76%
52 Europa22.77% 0.76%
88 Thisbe18.36% 0.61%
31 Euphrosyne17.02% 0.56%
13 Egeria15.927% 0.53%
29 Amphitrite15.24% 0.51%
87 Sylvia14.780.4% 0.49%
7 Iris13.759.5% 0.54%
48 Doris1250% 0.2%–0.4%
Total1868.0NA62.0%

, 7 Iris, 29 Amphitrite and 48 Doris, overlap with Europa or Psyche, so the first 12 asteroids in the chart above are likely to be the top dozen unless a hitherto unmeasured asteroid proves to be unexpectedly massive.
The largest asteroids with an accurately measured mass, because they have been studied by the probe Dawn, are 1 Ceres with a mass of, and 4 Vesta at. The third-largest asteroid with an accurately measured mass, because it has moons, is 87 Sylvia at.
For a more complete list, see List of Solar System objects by size. Other large asteroids such as 423 Diotima currently only have estimated masses.

Brightest from Earth

Only Vesta is regularly bright enough to be seen with the naked eye. The following asteroids can all reach an apparent magnitude brighter than or equal to the +8.3 attained by Saturn's moon Titan at its brightest, which was discovered 145 years before the first asteroid was found owing to its closeness to the easily observed Saturn.
None of the asteroids in the outer part of the asteroid belt can ever attain this brightness. Even Hygiea and Interamnia rarely reach magnitudes of above 10.0. This is due to the different distributions of spectral types within different sections of the asteroid belt: the highest-albedo asteroids are all concentrated closer to the orbit of Mars, and much lower albedo C and D types are common in the outer belt.
Those asteroids with very high eccentricities will only reach their maximum magnitude rarely, when their perihelion is very close to a heliocentric conjunction with Earth, or when the asteroid passes very close to Earth.
AsteroidMagnitude
when
brightest		Semi-
major
axis 		Eccentricity
of orbit		Diameter
Year of
discovery
99942 Apophis3.4*0.9220.1910.322004
4 Vesta5.202.3610.0891725291807
2 Pallas6.492.7730.2307255441802
1 Ceres6.652.7660.0799059521801
7 Iris6.732.3850.2314222001847
433 Eros6.81.4580.22272534 × 11 × 111898
6 Hebe7.52.4250.2017261861847
3 Juno7.52.6680.2581942331804
18 Melpomene7.52.2960.2187081411852
15 Eunomia7.92.6430.1871812681851
8 Flora7.92.2020.1562071281847
324 Bamberga8.02.6820.3382522291892
1036 Ganymed8.12.66570.533710321924
9 Metis8.12.3870.1214411901848
192 Nausikaa8.22.4040.2462161031879
20 Massalia8.32.4090.1428801451852

* Apophis will only achieve that brightness on April 13, 2029. It typically has an apparent magnitude of 20–22.

Slowest rotators

This list contains the slowest-rotating known minor planets with a period of at least 1000 hours, or 41 days, while most bodies have rotation periods between 2 and 20 hours. Also see Potentially slow rotators for minor planets with an insufficiently accurate period.
#Minor planet designationRotation period
ΔmagQuality
Orbit or familySpectral typeDiameter
Abs. mag
Refs
1.18800.62  NEOS0.78217.9
2.846 Lipperta16410.302  ThemisCBU:52.4110.26
3.2440 Educatio15610.802  FloraS6.5113.1
4.912 Maritima13320.183− MBA C82.14 9.30
5.9165 Raup13201.343− HungariaS4.6213.60
6.1235 Schorria12651.403  HungariaCX:5.0413.10
7.50719 Elizabethgriffin12560.422  EunomiaS3.4014.65
8.1234.20.692  VestianS2.9615.01
9.288 Glauke11700.903  MBA S32.2410.00
10.1167.40.802  MBA C5.3415.09
11.496 Gryphia10721.253  FloraS15.4711.61
12.4524 Barklajdetolli10691.262  FloraS7.1412.90
13.2675 Tolkien10600.752+FloraS9.8512.20
14.1007.70.862  MBA S1.5416.43

Fastest rotators

This list contains the fastest-rotating minor planets with a period of less than 100 seconds, or 0.027 hours. Bodies with a highly uncertain period, having a quality of less than 2, are highlighted in dark-grey. The fastest rotating bodies are all unnumbered near-Earth objects with a diameter of less than 100 meters .
Among the numbered minor planets with an unambiguous period solution are, a 60-meter sized stony NEO with a period of 352 seconds, as well as and, two main-belt asteroids, with a diameter of 0.86 and 2.25 kilometers and a period of 1.29 and 1.95 hours, respectively.

Orbital characteristics

Retrograde

s with orbital inclinations greater than 90° orbit in a retrograde direction., of the near-800,000 minor planets known, there are only 99 known retrograde minor planets. In comparison, there are over 2,000 comets with retrograde orbits. This makes retrograde minor planets the rarest group of all. High-inclination asteroids are either Mars-crossers or damocloids. Some of these are temporarily captured in retrograde resonance with the gas giants.
Minor planet
designation		Inclination First observed/
Discovery date		Condition codeObs. × arcCommentRefs
October 27, 2017079254—
September 21, 201817407—
October 8, 2015038805—
September 30, 2005112200Has a well-determined orbit
June 29, 2014696—
March 8, 201015—
September 13, 20150184680—
July 13, 201626075—
March 29, 2016091561—
August 5, 201418085—
January 20, 201539—
July 26, 20178720—
May 9, 2014095710—
April 16, 2013220—
January 20, 201346716Has a semi-major axis of 1254 AU, giving it the third largest semi-major axis of any known minor planet
April 14, 2010097888—
100.482°June 24, 20110364936—
101.295°July 6, 2017128014—
101.381°December 8, 2014023544—
101.828°January 17, 20131400—
103.396°May 31, 20081198550—
105.058°December 18, 200801608789—
105.113°August 14, 2016063879—
105.226°April 6, 201009072—
106.883°December 22, 201236674—
107.449°February 27, 20091584—
108.218°October 29, 20171638—
108.328°November 12, 200752204—
109.074°September 20, 201133654—
110.104°May 31, 20111234828—
110.226°October 5, 200551488—
110.504°May 21, 201071808—
112.224°November 1, 20054212Semi-major axis of 837AU, but has a somewhat short 81-day observation arc for such a large orbit
113.243°September 17, 201742160—
2016 LS114.338°June 27, 2015026688—
118.243°December 29, 2015033454—
118.797°July 28, 201023535—
118.970°September 4, 20020648554This outer-planet crosser is a damocloid and SDO.
121.179°August 5, 20108120—
123.886°June 2, 20107935—
125.356°June 8, 20130238336—
128.506°September 29, 201441334—
129.246°February 25, 2000242408A damocloid and SDO. Crosses all the outer planets except Neptune. Came within 0.03 AU of Ceres in 1930.
129.820°February 14, 2016023800—
130.333°July 5, 20130143510—
130.505°July 6, 20051662673—
133.437°September 1, 20064750Has an orbit with a data arc of 25 days
136.049°December 21, 201251066—
137.204°January 2, 201731785—
137.668°August 17, 2009143990—
138.330°October 9, 2016704—
139.682°December 23, 2016150718—
139.758°March 4, 2019576—
139.934°November 27, 20140115821—
140.773°July 1, 20100330022Perihelion at 9.4 AU, only has perihelion further out
141.645°November 24, 2011108—
143.912°January 25, 2010135032—
143.914°January 30, 2010374596Semi-major axis of 408 AU with perihelion at 6.1 AU in April 2012
144.034°November 1, 20120227052—
144.203°October 23, 201768442—
146.262°February 15, 20100129000—
146.883°April 18, 2012031408—
147.767°December 17, 20090195734—
148.419°November 5, 20160108624—
148.826°August 16, 2017145360—
150.148°March 5, 2006062310q=2.58 AU and period=274 yr
151.816°June 12, 19992905838A damocloid, Jupiter- and Saturn-crossing minor planet.
152.044°September 19, 20177590—
152.136°November 19, 20187351—
152.326°March 3, 20160181965—
152.438°February 2, 201751500—
154.367°April 29, 20090771834NEO that sometimes has the highest relative velocity to Earth of known objects that come within 0.5 AU of Earth. However, the relative velocity at 1 AU from the sun is less than 72 km/s.
154.736°June 6, 2013014148—
155.842°March 20, 2015748—
156.376°March 12, 201042460—
157.514°December 9, 201525580—
158.535°April 29, 2000225960—
159.092°December 9, 2015021120—
159.221°January 28, 201760—
160.027°October 9, 20123900—
2019 CR160.341°February 4, 2019136993—
20461 Dioretsa160.428°June 8, 19990256779most highly inclined known minor planet from June 8, 1999, to July 13, 2004
160.475°February 25, 20180261726—
160.735°May 4, 20176844—
161.695°June 23, 20150119280—
514107 Kaʻepaokaʻawela163.022°November 26, 2014074898A Jupiter co-orbital. First known example of a retrograde co-orbital asteroid with any of the planets. Might have an interstellar origin.
164.601°September 14, 200652849—
165.311°January 23, 20060207459—
165.525°July 13, 200423944Came within 0.80 AU of Saturn on 2007-Jun-05, most highly inclined known minor planet from 2004/07/13-2005/11/01
165.558°November 26, 20130186598—
167.030°February 28, 201626—
170.324°September 30, 200801058616—
170.569°October 26, 201434—
170.764°February 10, 201441938—
170.919°October 5, 20187270—
170.988°March 11, 2016018081—
172.138°June 3, 200648Has a data arc of only 2 days, but has a very high inclination
2005 VD172.872°November 1, 20050228965most highly inclined known minor planet from November 1, 2005, to June 1, 2013
175.095°June 1, 201361075Has the highest inclination of any known minor planet

the value given when the number of observations is multiplied by the observation arc; larger values are generally better than smaller values depending on residuals.

Highly inclined

Trojans

Viewed in detail

Spacecraft targets

NameDiameter
DiscoveredSpacecraftYearClosest
approach
Closest
approach
NotesLandmark
952Dawn2014–present '0.42Dawn took its first "close up" picture of Ceres in December 2014, and entered orbit in March 2015First likely dwarf planet visited by a spacecraft, largest asteroid visited by a spacecraft
529Dawn2011–20122100.76Dawn broke orbit on 5 September 2012 and headed to Ceres, where it arrived in March 2015First "big four" asteroid visited by a spacecraft, largest asteroid visited by a spacecraft at the time
120×100×80Rosetta201064.9Flyby on 10 July 2010Largest asteroid visited by a spacecraft at the time
56×24×21Galileo1993152Flyby; discovered DactylFirst asteroid with a moon visited by a spacecraft, largest asteroid visited by spacecraft at the time
66×48×46NEAR Shoemaker199749.5FlybyLargest asteroid visited by a spacecraft at the time
13×13×33NEAR Shoemaker1998–2001001998 flyby; 2000 orbited ; 2001 landingFirst asteroid landing, first asteroid orbited by a spacecraft, first near-Earth asteroid visited by a spacecraft
18.2×10.5×8.9Galileo1991262Flybyfirst asteroid visited by a spacecraft
4.6Rosetta2008800302FlybyFirst asteroid visited by the ESA
4.5×~2Chang'e 220120.70FlybyClosest asteroid flyby, first asteroid visited by China
4.0Stardust20021230Flyby
2.2×0.6Deep Space 119992612.7Flyby; followed by flyby of Comet Borrelly
0.5×0.3×0.2Hayabusa200500Landed; returned dust samples to EarthFirst asteroid with returned samples, smallest asteroid visited by a spacecraft, first asteroid visited by a non-NASA spacecraft
1.0Hayabusa22018–201900Multiple landers/rovers, sample returnFirst rovers on an asteroid
0.492OSIRIS-REx2018–present0 '0 Sample returnSmallest asteroid orbited, potentially hazardous object

Surface resolved by telescope or lightcurve

Landmark asteroids

Numbered minor planets that are also comets

NameCometary nameComment
2060 Chiron95P/ChironFirst centaur discovered in 1977, later identified to exhibit cometary behaviour. Also one of two minor planets known to have a ring system
4015 Wilson–Harrington107P/Wilson–HarringtonIn 1992, it was realized that asteroid 1979 VA's orbit matched it with the positions of the lost comet Wilson–Harrington
7968 Elst–Pizarro133P/Elst–PizarroDiscovered in 1996 as a comet, but orbitally matched to asteroid
60558 Echeclus174P/EcheclusCentaur discovered in 2000, comet designation assigned in 2006
118401 LINEAR176P/LINEAR Main-belt comet–asteroid discovered to have a coma on November 26, 2005

The above table lists only numbered asteroids that are also comets. Note there are several cases where a non-numbered minor planets turned out to be a comet, e.g. C/2001 OG108, which was provisionally designated.

Minor planets that were misnamed and renamed

In earlier times, before the modern numbering and naming rules were in effect, asteroids were sometimes given numbers and names before their orbits were precisely known. And in a few cases duplicate names were given to the same object. This led to a few cases where asteroids had to be renamed.
Minor planet nameDescription
330 AdalbertaAn object discovered March 18, 1892, by Max Wolf with provisional designation "1892 X" was named 330 Adalberta, but was lost and never recovered. In 1982 it was determined that the observations leading to the designation of 1892 X were stars, and the object never existed. The name and number 330 Adalberta was then reused for another asteroid discovered by Max Wolf on February 2, 1910, which had the provisional designation A910 CB.
525 Adelaide and 1171 RusthaweliaThe object A904 EB discovered March 14, 1904, by Max Wolf was named 525 Adelaide and was subsequently lost. Later, the object 1930 TA discovered October 3, 1930, by Sylvain Arend was named 1171 Rusthawelia. In those pre-computer days, it was not realized until 1958 that these were one and the same object. The name Rusthawelia was kept ; the name 525 Adelaide was reused for the object 1908 EKa discovered October 21, 1908, by Joel Hastings Metcalf.
715 Transvaalia and 933 SusiThe object 1911 LX discovered April 22, 1911, by H. E. Wood was named 715 Transvaalia. On April 23, 1920, the object 1920 GZ was discovered and named 933 Susi. In 1928 it was realized that these were one and the same object. The name Transvaalia was kept, and the name and number 933 Susi was reused for the object 1927 CH discovered February 10, 1927, by Karl Reinmuth.
864 Aase and 1078 MenthaThe object A917 CB discovered February 13, 1917, by Max Wolf was named 864 Aase, and the object 1926 XB discovered December 7, 1926, by Karl Reinmuth was named 1078 Mentha. In 1958 it was discovered that these were one and the same object. In 1974, this was resolved by keeping the name 1078 Mentha and reusing the name and number 864 Aase for the object 1921 KE, discovered September 30, 1921, by Karl Reinmuth.
1095 Tulipa and 1449 VirtanenThe object 1928 DC discovered February 24, 1928, by Karl Reinmuth was named 1095 Tulipa, and the object 1938 DO discovered February 20, 1938, by Yrjö Väisälä was named 1449 Virtanen. In 1966 it was discovered that these were one and the same object. The name 1449 Virtanen was kept and the name and number 1095 Tulipa was reused for the object 1926 GS discovered April 14, 1926, by Karl Reinmuth.
1125 China and 3789 ZhongguoThe object 1928 UF discovered October 25, 1928, by Zhang Yuzhe was named 1125 China, and was later lost. Later, the object was discovered on October 30, 1957, at Purple Mountain Observatory and was initially incorrectly believed to be the rediscovery of the object 1928 UF. The name and number 1125 China were then reused for the object, and 1928 UF remained lost. In 1986, the object was discovered and proved to be the real rediscovery of 1928 UF. This object was given the new number and name 3789 Zhongguo. Note Zhongguo is the Mandarin Chinese word for "China", in pinyin transliteration.
Asteroid 1317 and 787 MoskvaThe object 1914 UQ discovered April 20, 1914, by G. N. Neujmin was named 787 Moskva. The object 1934 FD discovered on March 19, 1934, by C. Jackson was given the sequence number 1317. In 1938, G. N. Neujmin found that asteroid 1317 and 787 Moskva were one and the same object. The sequence number 1317 was later reused for the object 1935 RC discovered on September 1, 1935, by Karl Reinmuth; that object is now known as 1317 Silvretta.

Landmark names

Asteroids were originally named after female mythological figures. Over time the rules loosened.
First asteroid with non-Classical and non-Latinized name: 64 Angelina
First asteroid with a non-feminine name: 139 Juewa or 141 Lumen
First asteroid with a non-feminized man's name: 903 Nealley
Lowest-numbered unnamed asteroid :

Landmark numbers

Many landmark numbers had specially chosen names for asteroids, and there was some debate about whether Pluto should have received number 10000, for example. This list includes some non-asteroids.

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