List of Solar System objects by size

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Masses of the largest objects (click to enlarge)

This is a list of Solar System objects by size, arranged in descending order of mean volumetric radius, and subdivided into several size classes. These lists can also be sorted according to an object's mass and, for the largest objects, volume, density and surface gravity, insofar as these values are available. This list contains the Sun, the planets, dwarf planets, many of the larger small Solar System bodies (which includes the asteroids), all named natural satellites, and a number of smaller objects of historical or scientific interest, such as comets and near-Earth objects.

The ordering may be different depending on whether one chooses radius or mass, because some objects are denser than others. For instance, Uranus is bigger than Neptune but less massive, and although Ganymede and Titan are larger than Mercury, they have less than half its mass. This means some objects in the lower tables, despite their smaller radii, may be more massive than objects in the upper tables because they have a higher density.

Many trans-Neptunian objects (TNOs) have been discovered, and their approximate locations in this list are shown, even though there can be a large uncertainty in their measurement.

Solar System objects more massive than 1021 kilograms (one yottagram [Yg]) are known or expected to be approximately spherical. Astronomical bodies relax into rounded shapes (ellipsoids), achieving hydrostatic equilibrium, when the gravity of their mass is sufficient to overcome the structural strength of their material. These are dubbed "regular". Objects made of ice become regular more easily than those made of rock, and many icy objects are spheroidal at far lower sizes. The cutoff boundary for regularity is somewhere between 100 km and 200 km in radius.[1]

The larger objects in the mass range between 1018 kg to 1021 kg (1 to 1000 zettagrams [Zg]), such as Tethys, Ceres, and Mimas, have relaxed to an oblate-spheroid equilibrium due to their gravity, whereas the less massive rubble piles (e.g. Amalthea and Janus) are roughly rounded, but not spherical, dubbed "irregular".

Spheroidal bodies typically have some polar flattening due to the centrifugal force from their rotation, and can sometimes even have quite different equatorial diameters (scalene ellipsoids such as Haumea). Unlike bodies such as Haumea, the "irregular"-shaped bodies, however, deviate significantly from the shape of an ellipsoid.

There can be difficulty in figuring out the diameter (within a factor of about 2) for typical objects beyond Saturn. (See 2060 Chiron as an example.) For TNOs there is some confidence in the diameters, but for non-binary TNOs there is no real confidence in the masses/densities. Many TNOs are often just assumed to have Pluto's density of 2.0 g/cm3, but it is just as likely that they have a comet-like density of only 0.5 g/cm3.[2] For example, if a TNO is poorly assumed to have a mass of 3.59×1020 kg based on a radius of 350 km with a density of 2 g/cm3 and is later discovered to only have a radius of 175 km with a density of 1 g/cm3, the mass estimate would be only 2.24×1019 kg.

The sizes and masses of many of the moons of Jupiter and Saturn are fairly well known due to numerous observations and interactions of the Galileo and Cassini orbiters. But many of the moons with a radius less than ~100 km, such as Jupiter's Himalia, still have unknown masses.[3] Again, as we get further from the Sun than Saturn, things get less clear. There has not yet been an orbiter around Uranus or Neptune for long-term study of their moons. For the small outer irregular moons of Uranus, such as Sycorax, which were not discovered by the Voyager 2 flyby, even different NASA web pages, such as the National Space Science Data Center[4] and JPL Solar System Dynamics,[3] have somewhat contradictory size and albedo estimates depending on which research paper is being cited.

Data for objects has varying reliability including uncertainties in the figures for mass and radius, and irregularities in the shape and density, with accuracy often depending on how close it is to Earth or if it has been visited by a probe.

List[edit]

Objects above ≈400 km in radius[edit]

It was once thought that everything above this size is probably in hydrostatic equilibrium (HE), though some bodies listed near the end might not be if their estimated or measured size were "grossly in error" or their composition primarily rocky.[5] However, Rhea is the smallest body where detailed measurements have been made and are consistent with hydrostatic equilibrium,[6] whereas Iapetus is the largest determined not to be in hydrostatic equilibrium,[7] though it does have an ellipsoidal shape (i.e. it is round).

A lot of the values are manually calculated assuming sphericity. The size of solid bodies does not include an object's atmosphere. For example, Titan looks bigger than Ganymede, but its solid body is smaller. For the gas giants, the "radius" is the point at which the atmosphere reaches 1 bar of atmospheric pressure.[8] The radius of Saturn's main rings is 136,775 km.

Body Image Mean radius
(km)
Mean radius
(R)
Volume
(109 km3)
Volume
(V)
Mass
×1021 kg
(Yg)
Mass
(M)
Density
g/cm3
Surface gravity
(m/s2)
Surface gravity
()
Type of object Shape
Sun The Sun by the Atmospheric Imaging Assembly of NASA's Solar Dynamics Observatory - 20100819.jpg 696342±65[9] 109.3 1,414,300,000 1,305,700 1,988,550,000 333,000 1.408 274.0 28.02 star round (HE)
Jupiter Jupiter by Cassini-Huygens.jpg 69911±6 10.97 1,431,280 1,321 1,898,600 317.83 1.326 24.79 2.535 planet (gas giant)—has rings round (HE)
Saturn Saturn closeup.jpg 58232±6
(w/o rings)
9.14 827,130 764 568,460 95.159 0.687 10.445 1.06 planet (gas giant)—has rings round (HE)
Uranus Uranus2.jpg 25362±7 3.98 68,340 63.1 86,832 14.536 1.27 8.87 0.90 planet (gas giant)—has rings round (HE)
Neptune Neptune.jpg 24622±19 3.86 62,540 57.7 102,430 17.147 1.638 11.15 1.140 planet (gas giant)—has rings round (HE)
Earth The Earth seen from Apollo 17.jpg 6371.0 1 1,083.21 1 5,973.6 1 5.514 9.78033 0.99732 planet (terrestrial) round (HE)
Venus Venus-real.jpg 6051.8±1.0
(w/o gas)
0.950 928.43 0.857 4,868.5 0.815 5.243 8.872 0.905 planet (terrestrial) round (HE)
Mars Mars Valles Marineris.jpeg 3389.5±0.2 0.532 163.18 0.151 641.85 0.107 3.9335±0.0004 3.7 0.38 planet (terrestrial) round (HE)
Ganymede
Jupiter III
Noaa ganymede.jpg 2634.1±0.3 0.413 76.30 0.0704 148.2 0.0248 1.936 1.428 0.15 satellite of Jupiter round (HE)
Titan
Saturn VI
Two Halves of Titan.png 2576±2
(w/o gas)
0.404 71.52 0.0660 134.5 0.0225 1.8798±0.0044 1.354 0.14 satellite of Saturn round (HE)
Mercury Mercury in color - Prockter07 centered.jpg 2439.7±1.0 0.383 60.83 0.0562 330.2 0.0553 5.427 3.7 0.38 planet (terrestrial) round (HE)
Callisto
Jupiter IV
Callisto.jpg 2410.3±1.5 0.378 58.65 0.0541 107.6 0.018 1.8344±0.0034 1.23603 0.126 satellite of Jupiter round (HE)
Io
Jupiter I
Io highest resolution true color.jpg 1821.6±0.5 0.286 25.32 0.0234 89.3 0.015 3.528±0.006 1.797 0.183 satellite of Jupiter round (HE)
Moon
Earth I
FullMoon2010.jpg 1737.1 0.273 21.958 0.0203 73.5 0.0123 3.3464 1.625 0.166 satellite of Earth round (HE)
Europa
Jupiter II
Europa-moon.jpg 1560.8±0.5 0.245 15.93 0.0147 48 0.00803 3.013±0.005 1.316 0.134 satellite of Jupiter round (HE)
Triton
Neptune I
Triton Voyager 2.jpg 1353.4±0.9 0.212 10.38 0.0096 21.5 0.00359 2.061 0.782 0.0797 satellite of Neptune round
PlutoR
134340
Pluto-map-hs-2010-06-c180.jpg 1184±10[10] 0.185 7 0.0066 13.105 0.0022 2.03±0.06 0.61 0.062 dwarf planetplutino round
ErisR
136199
Eris and dysnomia2.jpg 1163±6[11] 0.182 7 0.007 16.7[12] 0.0027 2.52±0.05 0.662 0.0677 dwarf planetSDObinary round
Titania
Uranus III
Titania (moon) color cropped.jpg 788.4±0.6 0.124 2.06 0.0019 3.526 0.00059 1.711±0.005 0.378 0.0385 satellite of Uranus round
Rhea
Saturn V
PIA07763 Rhea full globe5.jpg 763.8±1.0 0.12 1.87 0.0017 2.3166 0.00039 1.236±0.005 0.26 0.027 satellite of Saturn round (HE)
Oberon
Uranus IV
Voyager 2 picture of Oberon.jpg 761.4±2.6 0.12 1.85 0.0017 3.014 0.0005 1.63±0.05 0.347 0.035 satellite of Uranus round
Iapetus
Saturn VIII
Iapetus as seen by the Cassini probe - 20071008.jpg 734.5±2.8 0.113 1.55 0.0014 1.9739 0.00033 1.088±0.013 0.223 0.0227 satellite of Saturn round (not in technical HE)
MakemakeR
136472
Makemake hubble.png 715±7 1.7 3 0.00067 1.7[13] 0.4 dwarf planetcubewano round
HaumeaR
136108
715[14] 0.117 1.3–1.6 0.001 4.006 0.00069 2.55[15] 0.44 0.045 dwarf planetresonant KBO (7:12)—trinary round (scalene ellipsoid)
2007 OR10
225088
640±100[16] 0.1 1.0981 0.00101 resonant KBO (3:10) unknown
Charon
Pluto I
Charon.png 603.5±1.5 0.095 0.87 0.0008 1.52 0.00025 1.65±0.06 0.279 0.028 satellite of Pluto round
Umbriel
Uranus II
Umbriel moon 1.gif 584.7±2.8 0.092 0.84 0.0008 1.2 0.00020 1.39±0.16 0.234 0.024 satellite of Uranus round
Ariel
Uranus I
Ariel-NASA.jpg 578.9±0.6 0.091 0.81 0.0008 1.35 0.00022 1.66±0.15 0.269 0.027 satellite of Uranus round
Dione
Saturn IV
Dione-PIA07746.jpg 561.4±0.4 0.088 0.73 0.0007 1.096 0.000183 1.478±0.003 0.232 0.0236 satellite of Saturn round (not in technical HE)
Quaoar
50000
Quaoar PRC2002-17e.jpg 555±3 1.6[17] 0.0003 2.2±0.4[18] 0.125 cubewanobinary unknown
Tethys
Saturn III
PIA07738 Tethys mosaic contrast-enhanced.jpg 531.1±0.6 0.083 0.624 0.0006 0.6173 0.000103 0.984±0.003[19] 0.145 0.015 satellite of Saturn round (not in technical HE)
SednaRA
90377
Sedna PRC2004-14d.jpg 500±80 0.08 sednoid[20] unknown
Ceres
1
Ceres optimized.jpg 476.2±1.7[21] 0.076 0.437 0.0004 0.95 0.000159 2.077±0.036 0.27 0.0275 dwarf planetbelt asteroid round
2002 MS4
307261
467±24 0.07 cubewano[20] unknown
OrcusR
90482
458±13 0.07 2.47[22] plutinobinary unknown
Salacia
120347
425±23 0.07 1.16+0.59
−0.36
[23]
cubewanobinary unknown

Objects between ≈400 and ≈200 km in radius[edit]

Most objects in this size range are expected to be round. All the satellites except Proteus are round, though those that have their shapes carefully measured are not in technical hydrostatic equilibrium (HE). The asteroid 10 Hygiea is not, and 2 Pallas and 4 Vesta are borderline. Like the satellites, TNOs in this size range are expected to be round, assuming the estimated size is correct.

Body Image Mean radius
(km)
Mass
×1021 kg
(Yg)
Density

g/cm3
Type of object Shape
2002 AW197R
55565
380±20 cubewano unknown
2013 FY27 376 SDO unknown
2003 AZ84R
208996
360±30 plutinobinary unknown
2002 UX25R
55637
350±10 0.82[24] cubewanobinary unknown
Varda9
174567
350±40 cubewanobinary unknown
2004 GV9R
90568
340±40 cubewano unknown
Dysnomia
Eris I
340±30 satellite of Eris unknown
2005 RN439
145452
340±40 cubewano unknown
Varuna*
20000
334[25] 0.37 0.992[15] cubewano unknown
IxionR
28978
325+130
−110
plutino unknown
2007 JJ43
278361
ca. 300 cubewano unknown
2007 UK1269
229762
300±40 SDO unknown
Chaos
19521
300±70 cubewano unknown
2010 KZ39 ca. 300 cubewano[26] unknown
2012 VP113 ca. 300 sednoid unknown
2010 RF43 ca. 300 SDO unknown
2005 RM439
145451
ca. 300 SDO unknown
2001 UR1639
42301
ca. 300 SDO[20] unknown
2002 TC302
84522
290±50 resonant KBO (2:5) unknown
2003 UZ4139 ca. 280 plutino unknown
2008 ST291 ca. 280 SDO unknown
2010 RE64 ca. 280 SDO unknown
2010 FX86 ca. 280 cubewano unknown
2002 XV93 280±10 plutino[20] unknown
2006 QH1819 ca. 280 SDO unknown
Pallas$
2
PallasHST2007.jpg 270±10 0.211 2.8[27] belt asteroid uncertain
2004 XR190 ca. 270 SDO[20] unknown
Vesta$
4
Vesta full mosaic.jpg 262.7±0.1[28] 0.259076±0.000001 3.456[28] belt asteroid rounded (not in technical hydrostatic equilibrium:
frozen-in ellipsoidal shape and large impact basins)[29][30]
2003 VS2
84922
260±20 plutino[20] unknown
2004 TY364*
120348
ca. 260 cubewano unknown
2010 VK201 ca. 260 cubewano[20] unknown
2003 QX113 ca. 250 SDO[20] unknown
Enceladus
Saturn II
Enceladus from Voyager.jpg 252.1±0.2 0.1080±0.0001 1.609±0.005 satellite of Saturn round (not in technical HE: frozen-in ellipsoidal shape)
2005 UQ5139
202421
250±40 cubewano unknown
2010 TY53 unknown extended centaur[20] unknown
2011 GM27 unknown SDO unknown
2006 HH123 unknown unknown unknown
2010 TJ unknown SDO[20] unknown
2010 VZ98 unknown SDO[20] unknown
2011 FW62 unknown cubewano unknown
2010 EK139 240±70 SDO unknown
Miranda
Uranus V
Miranda.jpg 235.8±0.7 0.0659±0.0075 1.20±0.15 satellite of Uranus round
2005 TB190
145480
230±30 detached object[20] unknown
1999 DE9
26375
230±20 resonant KBO (2:5) unknown
2003 FY128
120132
230±10 SDO[20] unknown
HuyaR
38628
229±5 plutino unknown
2002 KX149
119951
unknown cubewano unknown
2002 VR128
84719
220±20 plutino[20] unknown
2002 WC19
119979
unknown twotinobinary unknown
10 Hygiea$ 215±4 belt asteroid irregular
Proteus
Neptune VIII (8)
Proteus (Voyager 2).jpg 210±7 0.044 1.3[31] satellite of Neptune irregular
2005 QU1829
303775
210±40 SDO[20] unknown
2004 NT33 210±40 cubewano[20] unknown
1999 CD158 ca. 210 resonant KBO (4:7) unknown
2004 PF115
175113
203±43 plutino unknown
1998 SN165*
35671
200±20 cubewano unknown
2001 QF298 200±20 plutino[20] unknown
2000 YW134*
82075
ca. 200 SDO[20] unknown
1996 GQ21*
26181
ca. 200 SDO[20] unknown

Selected objects between 200 and 100 km in radius[edit]

Satellites of Saturn
Satellites of Neptune

Objects between 200 and 100 km in radius (400 and 200 km in diameter). The largest of these may lie above the boundary for hydrostatic equilibrium, but most are irregular. Most of the trans-Neptunian objects listed with a radius smaller than 200 km have "assumed sizes based on a generic albedo of 0.09" since they are too far away to directly measure their sizes with existing instruments. Mass switches from 1021 kg to 1018 kg (Zg). Main-belt asteroids have orbital elements constrained by (2.0 AU < a < 3.2 AU; q > 1.666 AU) according to JPL Solar System Dynamics (JPLSSD).[32] This list is not complete, missing many poorly known TNOs.[20]

Body Image Mean radius
(km)
Mass
×1018 kg
(Zg)
Type of object Shape
Mimas
Saturn I
Mimas moon.jpg 198.2±0.4 37.49±0.03 satellite of Saturn round (smallest known body currently having an ellipsoidal shape,
but it is technically not in hydrostatic equilibrium)
Hiʻiaka
Haumea I
195[33] 20 satellite of Haumea unknown
Vanth
Orcus I
190±50[22] satellite of Orcus unknown
Ilmarë
Varda I
180±20 satellite of Varda unknown
1996 TL66
15874
170±10 SDO unknown
Nereid
Neptune II
Nereid-Voyager2.jpg
170±30 satellite of Neptune irregular
2004 XA192
230965
170±60 SDO unknown
2001 FP185
82158
166±28 SDO unknown
Interamnia M
704
163±1 37 belt asteroidF-type irregular
Europa$
52
52Eur-LB1-richfield.jpg
158±4 16.5 belt asteroidC-type irregular[34]
Davida$
511
145±10 43.8 belt asteroidC-type irregular
Sylvia$
87
CMSylvia.png
143±5 14.78 belt asteroid (outer)—X-typetrinary irregular[34]
Actaea
Salacia I
140±10 satellite of 120347 Salacia unknown
Cybele$
65
136±6 17.8 belt asteroid (outer)—C-type irregular
Juno$
3
Juno 4 wavelengths.jpg
136±11[35] 26.7 belt asteroidS-type irregular[34]
Hyperion
Saturn VII
Hyperion true.jpg
135±4 5.58 satellite of Saturn irregular
Eunomia$
15
134±7 31.2 belt asteroidS-type irregular[34]
Camilla$
107
129±7 11.2 belt asteroid (outer)—C-typebinary irregular[36]
EuphrosyneM
31
128±3 6.23 belt asteroidC-type irregular
16 Psyche$ 127±2 21.9 belt asteroidM-type irregular
2005 RR43
145453
126[37] cubewanoHaumea family unknown
Chariklo
10199
124±9 centaur unknown—has rings
Sila9
79360
125±50 11 cubewanobinary (Nunam) unknown
BambergaM
324
117±4 10 belt asteroidC-type
Patientia
451
117±5 belt asteroid irregular
Chiron*
2060
95P/Chiron
116±7 centaur unknown
Thisbe $
88
113±6 10.5 M belt asteroidB-type irregular[36]
Hektor
624
624Hektor-LB1-mag15.jpg
113±8 10 Jupiter trojan (L4)—binary irregular
Ceto
65489
112±10 5.4[38] extended centaurbinary unknown
Herculina
532
111±2 belt asteroidS-type irregular[34]
Doris
48
111±4 belt asteroid irregular
Nunam
79360
110±50 satellite of Sila unknown
EugeniaM
45
107 ± 2 5.69 belt asteroidF-typetrinary irregular[34]
Phoebe $
Saturn IX
Phoebe cassini.jpg
106.5±0.7 8.29±0.01 satellite of Saturn formerly round[39]
Amphitrite$
29
106±3 11.8 belt asteroidS-type irregular[34]
Bienor
54598
105±15 centaur unknown
Deucalion
53311
ca. 105 cubewano unknown
Diotima
423
104±3 belt asteroidC-type irregular[40]
EgeriaM
13
104±4 16.3 belt asteroidG-type irregular
Fortuna $
19
104±6 12.7 belt asteroidG-type irregular
Aurora
94
102±2 belt asteroid irregular[41]
Iris$
7
7Iris-LB1-richfield-mag10.jpg
100±5 13.6 belt asteroidS-type irregular
Daphne
41
41Daphne-Keck.jpg
100±5 belt asteroid irregular
Themis M
24
100±10 11.3 belt asteroidC-typeThemis family

Selected objects between 100 and 50 km in radius[edit]

Satellites of Jupiter
Satellites of Saturn
Satellites of Uranus
Satellites of Neptune

Objects 100 and 50 km in radius (200 km to 100 km in average diameter). The listed objects currently include most objects in the asteroid belt and moons of the gas giants in this size range, but many newly discovered objects in the outer Solar System are missing, such as those included in the following reference.[20] Asteroid spectral types are mostly Tholen, but some might be SMASS.

Body Image Mean radius
(km)
Mass
×1018 kg
(Zg)
Type of object/Notes
702 Alauda
702Ala-mag13-occult.jpg
97±2 6.05 Main-belt asteroidC-typebinary
Larissa
Neptune VII (7)
Larissa 1.jpg
97±3 Satellite of Neptune
Ursula
375
375Ursula-LB1.jpg
96±2 Main-belt asteroid
121 HermioneM 121Hermione (Lightcurve Inversion).png 95 km[42] 5.38 Outer main-belt asteroidC-typebinary
372 Palma 96±2 Main-belt asteroid
9 Metis$ 95 ± ?? 11.3 Main-belt asteroid
128 Nemesis 92±3 7 Main-belt asteroidC-type
6 Hebe $ 93 ± ?? 12.8 Main-belt asteroidS-type
5145 Pholus 92±8 6.6 Centaur
154 Bertha 93±1 Main-belt asteroidC-type
76 Freia 92±2 6.5 Outer main-belt asteroidCybele
130 ElektraM 91±6 6.6 Main-belt AsteroidG-typebinary
Rhadamanthus
38083
40–140 Kuiper belt object
Janus$
Saturn X (10)
PIA12714 Janus crop.jpg
89.5±1.4 1.912 Satellite of Saturn
259 Aletheia 95±3 5.97 Main-belt asteroid
Galatea
Neptune VI (6)
Galatea moon.jpg
88±4 2.12 Satellite of Neptune
88611 Teharonhiawako 80 ± ?? Trans-Neptunian objectcubewanobinary
42355 Typhon 81±4 Trans-Neptunian objectbinary
120 Lachesis 87 ± ?? 5.5 Main-belt asteroid
747 Winchester 85±3 Main-belt Asteroid
153 Hilda 85 ± ?? 5.2 Main-belt asteroidHildas
Himalia M
Jupiter VI (6)
Cassini-Huygens Himalia.jpg
85 ± ?? 4.19 [43] Satellite of JupiterHimalia group
Namaka
Haumea II
assumed ca. 85 2 Satellite of Haumea
Puck
Uranus XV (15)
Puck.png
81±2[44] Satellite of Uranus
96 Aegle 84 ± 3 5.1 Main-belt asteroid
241 Germania 89 ± 4 5.05 Main-belt asteroidC-type
194 Prokne 85 ± 3 5 Main-belt asteroidC-type
566 Stereoskopia 84[45] Outer main-belt asteroidCybele
Amalthea
Jupiter V (5)
Amalthea (moon).png
84±2 2.08 ± 0.15 Satellite of Jupiter$
911 Agamemnon 83 ± ?? Jupiter trojan
22 Kalliope 90 ± 2 8.09M Main-belt asteroidM-typebinary
66652 Borasisi 70–90?[citation needed] Trans-Neptunian objectcubewanobinary
386 Siegena 85 ± 4 Main-belt asteroidC-type
59 Elpis 82 ± 3 Main-belt asteroid
1437 Diomedes 82 ± 2 4.6 Jupiter trojan
444 GyptisM 82 ± 5 12.5 Main-belt asteroidC-type
409 Aspasia 88 ± 2 4.42 Main-belt asteroidC-type
20461 Dioretsa unknown Centaur[46]Damocloid
209 Dido 70 ± 5 4.28 Main-belt asteroidC-type
334 Chicago 84 ± 4 Main-belt asteroidC-type
804 Hispania 74 ± 2 9.95 Main-belt asteroidP-type
185 Eunike 80 ± 3 4.09 Main-belt asteroid
139 Juewa 81 ± 4 4 Main-belt asteroid
85 Io 80 ± ?? 3.4 Main-belt asteroid
165 Loreley 82 ± 4 3.91 Main-belt asteroidC-type
790 Pretoria 80.49[37] Outer main-belt asteroidCybele
173 Ino 80 ± 3 Main-belt asteroidC-type
Altjira 9
148780
60–100 Trans-Neptunian objectcubewano
354 Eleonora 77 ± 3 Main-belt asteroidS-type
39 Laetitia 76.9[37] 3.5 Main-belt asteroid
14 Irene 76 ± ?? 8.2 Main-belt asteroid
89 Julia 74 ± 4 3.6 Main-belt asteroidS-type
536 Merapi 76 ± 2 Main-belt asteroid
776 Berbericia 76 ± 2 Main-belt asteroid
145 Adeona 75 ± 3 3.6 Main-belt asteroidAdena
150 Nuwa 73 ± 5 3.62 Main-belt asteroidC-type
Despina
Neptune V (5)
Despina.jpg
75±3 Satellite of Neptune
Sycorax
Uranus XVII (17)
75 (assumed) 2.3 Satellite of Uranus
Manwë
385446
ca. 75 Resonant KBO (4:7)
Sycorax
Uranus XVII (17)
75 (assumed) 2.3 Satellite of Uranus
49 Pales M 74.9[47] 2.69 Main-belt asteroidC-type
S/2007 (148780) 1
Altjira I
50–90 Secondary of 148780 Altjira
117 Lomia ca. 70 3.4 Main-belt asteroidC-type
238 Hypatia ca. 70 Main-belt asteroidC-type
168 Sibylla ca. 70 3.42 Main-belt asteroidC-type
283 EmmaM ca. 70 1.38 Main-belt asteroidbinary
51 Nemausa ca. 70 Main-belt asteroid
106 Dione ca. 70 Main-belt asteroidG-type
137 Meliboea ca. 70 3.2 Main-belt asteroid
20 Massalia$ ca. 70 5.67 Main-belt asteroid
211 Isolda ca. 70 3.07 Main-belt asteroidC-type
1172 Äneas ca. 70 Jupiter trojan
144 Vibilia ca. 70 3 Main-belt asteroid
508 Princetonia ca. 70 Main-belt asteroid
895 Helio ca. 70 Main-belt asteroidB-type
361 Bononia ca. 70 Main-belt asteroidD-type
420 Bertholda ca. 70 Main-belt asteroidP-type
93 Minerva ca. 70 2.9 Main-belt asteroidC-typetrinary
617 Patroclus ca. 70 Jupiter trojanbinary
308 Polyxo ca. 70 Main-belt asteroidT-type
18 Melpomene ca. 70 3 Main-belt asteroid
268 Adorea ca. 70 Main-belt asteroid
349 Dembowska ca. 70 Main-belt asteroidR-type
489 Comacina ca. 70 Main-belt asteroid
69 Hesperia ca. 70 2.76 Main-belt asteroidM-type
54 Alexandra ca. 70 Main-belt asteroid
762 Pulcova ca. 70 Main-belt asteroidC-typebinary
Pabu
Borasisi I
ca. 70 Secondary of 66652 Borasisi
196 Philomela ca. 70 Main-belt asteroidS-type
212 Medea ca. 70 2.64 Main-belt asteroid
95 Arethusa ca. 70 2.6 Main-belt asteroid
Portia
Uranus XII (12)
68±4 1.7 Satellite of Uranus
588 Achilles ca. 70 Jupiter trojan
690 Wratislavia
690Wrat-mag13-100yrs.jpg
ca. 70 Main-belt asteroid
111 Ate ca. 70 Main-belt asteroidC-type
247 Eukrate ca. 70 Main-belt asteroidC-type
705 Erminia ca. 70 Main-belt asteroid
471 Papagena ca. 70 Main-belt asteroidC-type
Phorcys
Ceto I
86±5 1.67[38] Satellite of 65489 Ceto
147 Protogeneia ca. 70 2.5 Main-belt asteroid
Menoetius
Patroclus I
ca. 70 Secondary of 617 Patroclus
344 Desiderata ca. 70 Main-belt asteroidC-type
146 Lucina ca. 70 2.4 Main-belt asteroid
141 Lumen ca. 70 1.6 Main-belt asteroidC-type
356 Liguria ca. 70 Main-belt asteroid
11 Parthenope ca. 70 6.15M Main-belt asteroid
187 Lamberta ca. 70 2.37 Main-belt asteroidC-type
419 Aurelia ca. 60 Main-belt asteroidF-type
200 Dynamene ca. 60 Main-belt asteroid
8 Flora 8Flora (Lightcurve Inversion).png ca. 60 8.47 Main-belt asteroidS-typeFlora
712 Boliviana ca. 60 Main-belt asteroidX-type
654 Zelinda ca. 60 Main-belt asteroid
426 Hippo ca. 60 Main-belt asteroid
47 Aglaja pic ca. 60 Main-belt asteroidC-type
279 Thule ca. 60 Main-belt asteroidD-type
92 Undina ca. 60 2.1 Main-belt asteroidM-type
1173 Anchises ca. 60 Jupiter trojan
1143 Odysseus ca. 60 Jupiter trojan (L4)
469 Argentina ca. 60 Main-belt asteroidCybele
159 Aemilia ca. 60 1.4 Main-belt asteroid
405 Thia ca. 60 Main-belt asteroidC-type
602 Marianna ca. 60 Main-belt asteroid
46 Hestia ca. 60 3.5[48]–21[49] Main-belt asteroid
216 Kleopatra Kleopatra.jpg ca. 60 Main-belt asteroidM-typetrinary
104 Klymene ca. 60 2 Main-belt asteroid
410 Chloris ca. 60 Main-belt asteroidC-type
134 Sophrosyne ca. 60 2 Main-belt asteroid
328 Gudrun ca. 60 1.94 Main-belt asteroidS-type
1867 Deiphobus ca. 60 Jupiter trojan
68 Leto ca. 60 Main-belt asteroidS-type
70 Panopaea ca. 60 Main-belt asteroidC-type
Sawiskera
Teharonhiawako I
ca. 60 Secondary of 88611 Teharonhiawako
127 Johanna ca. 60 Main-belt asteroid
276 Adelheid ca. 60 Main-belt asteroid
176 Iduna ca. 60 Main-belt asteroidG-type
156 Xanthippe ca. 60 Main-belt asteroidS-type
28 Bellona ca. 60 Main-belt asteroidC-type
86 Semele ca. 60 Main-belt asteroidC-type
78 Diana ca. 60 Main-belt asteroidC-type
381 Myrrha ca. 60 Main-belt asteroidC-type
225 Henrietta ca. 60 1.83 Main-belt asteroidC-typeCybele
618 Elfriede ca. 60 Main-belt asteroidC-type
105 Artemis ca. 60 1.8 Main-belt asteroidC-type
81 Terpsichore ca. 60 Main-belt asteroidC-type
5 Astraea ca. 60 2.9 Main-belt asteroid
74 Galatea ca. 60 1.8 Main-belt asteroidC-type
350 Ornamenta ca. 60 Main-belt asteroidC-type
772 Tanete ca. 60 Main-belt asteroidC-type
476 Hedwig ca. 60 Main-belt asteroid
1093 Freda ca. 60 Main-belt asteroid
171 Ophelia ca. 60 Main-belt asteroidC-typeThemis
909 Ulla ca. 60 Main-belt asteroid
3317 Paris ca. 60 Jupiter trojan
203 Pompeja ca. 60 Main-belt asteroid
3063 Makhaon ca. 60 1.6 Jupiter trojan
2006 SQ372
308933
ca. 60 TNO
38 Leda ca. 60 1.6 Main-belt asteroid
360 Carlova ca. 60 Main-belt asteroid
521 Brixia ca. 60 Main-belt asteroid
490 Veritas ca. 60 Main-belt asteroid—Veritas
466 Tisiphone ca. 60 Main-belt asteroidC-type
53 Kalypso ca. 60 Main-belt asteroid
2241 Alcathous ca. 60 Jupiter trojan
388 Charybdis ca. 60 Main-belt asteroidC-type
34 Circe ca. 60 1.5 Main-belt asteroidC-type
Epimetheus
Saturn XI (11)
PIA09813 Epimetheus S. polar region.jpg
58±2 0.5304[50] Satellite of Saturn$
596 Scheila ca. 60 Main-belt asteroid
56 Melete ca. 60 1.5 Main-belt asteroid
129 Antigone ca. 60 2 Main-belt asteroid—nickel–iron
12 Victoria ca. 60 Main-belt asteroidS-type
57 Mnemosyne ca. 60 Main-belt asteroid
545 Messalina ca. 60 Main-belt asteroid
2797 Teucer ca. 60 Jupiter trojan (L4)
2920 Automedon ca. 60 Jupiter trojan (L4)
91 Aegina ca. 50 1.4 Main-belt asteroidC-type
140 Siwa ca. 50 1.4 Main-belt asteroid
814 Tauris ca. 50 Main-belt asteroid
595 Polyxena ca. 50 Main-belt asteroid
230 Athamantis ca. 50 Main-belt asteroidS-type
659 Nestor ca. 50 Jupiter trojan
37 Fides ca. 50 1.3 Main-belt asteroidS-type
514 Armida ca. 50 Main-belt asteroid
23 Thalia ca. 50 1.3 Main-belt asteroidS-type
739 Mandeville ca. 50 Main-belt asteroidX-type
40 Harmonia ca. 50 1.3 Main-belt asteroidS-type
181 Eucharis ca. 50 1.2 Main-belt asteroidK-type
346 Hermentaria ca. 50 Main-belt asteroidS-type
357 Ninina ca. 50 Main-belt asteroid
506 Marion ca. 50 Main-belt asteroidC-type
365 Corduba ca. 50 Main-belt asteroidC-type
36 Atalante ca. 50 Main-belt asteroid
713 Luscinia ca. 50 Main-belt asteroidC-type
1269 Rollandia ca. 50 Main-belt asteroid
164 Eva ca. 50 Main-belt asteroidC-type
98 Ianthe ca. 50 1.2 Main-belt asteroidC-type
240 Vanadis ca. 50 Main-belt asteroidC-type
221 Eos ca. 50 Main-belt asteroidK-type
788 Hohensteina ca. 50 Main-belt asteroid
791 Ani ca. 50 Main-belt asteroid
1208 Troilus ca. 50 Jupiter trojan
192 Nausikaa ca. 50 Main-belt asteroidS-type
63 Ausonia ca. 50 1.1 Main-belt asteroidS-type
35 Leukothea ca. 50 1.1 Main-belt asteroidC-type
570 Kythera ca. 50 Main belt asteroid
233 Asterope ca. 50 Main belt asteroidT-type
4063 Euforbo ca. 50 Jupiter trojan
1583 Antilochus ca. 50 Jupiter trojan
1390 Abastumani ca. 50 Main-belt asteroid
522 Helga ca. 50 Main-belt asteroidCybele
175 Andromache ca. 50 Main-belt asteroidC-type
191 Kolga ca. 50 1.08 Main-belt asteroidC-type
663 Gerlinde ca. 50 Main-belt asteroid
626 Notburga ca. 50 Main-belt asteroid
387 Aquitania ca. 50 Main-belt asteroidS-type
42 Isis ca. 50 Main-belt asteroidS-type
30 Urania ca. 50 Main-belt asteroidS-type

Examples of objects between 50 km and 20 km in radius[edit]

There are easily tens of thousands of objects 50 km in radius or smaller[clarification needed], but only a fraction have been explored. The number of digits is not an endorsement of significant figures. The table switches from ×1018 kg to ×1015 kg (Eg), and many of these mass values are assumed. (See also: List of minor planets.)

Satellites of Jupiter
Satellites of Saturn
Satellites of Uranus
Satellites of Neptune
Satellites of Pluto
Body Image Mean radius
(km)
Mass
×1015 kg
(Eg)
Type of object
50 Virginia ca. 50 Asteroid
114 Kassandra ca. 50 1000 Main-belt asteroidT-type
1021 Flammario ca. 50 Asteroid
162 Laurentia ca. 50 Main-belt asteroid
401 Ottilia ca. 50 Main-belt asteroid
Thebe
Jupiter XIV (14)
Thebe.jpg
ca. 50 Satellite of Jupiter
148 Gallia ca. 50 980 Main-belt asteroidR-type
404 Arsinoe ca. 50 Main-belt asteroidC-type
27 Euterpe ca. 50 Main-belt asteroidS-type
773 Irmintraud ca. 50 AsteroidD-type
21 Lutetia ca. 50 1700 [51] Main-belt asteroidM-type
62 Erato ca. 50 910 Main-belt asteroidThemis
26 Proserpina ca. 45 900 Asteroid
345 Tercidina ca. 45 Main-belt asteroidC-type
Juliet
Uranus XI
ca. 45 Satellite of Uranus
58 Concordia ca. 45 850 Asteroid
229 Adelinda ca. 45 Main-belt asteroidC-type
379 Huenna ca. 45 480 Main-belt asteroidC-type
Nix
Pluto II
ca. 45 70 Satellite of Pluto
103 Hera ca. 45 790 Asteroid
17 Thetis
17Thetis-LB1.jpg
ca. 45 1200 Asteroid
143 Adria ca. 45 760 Main-belt asteroid
109 Felicitas ca. 45 750 Asteroid
100 Hekate ca. 45 1000 Asteroid
90 Antiope A ca. 45 410 AsteroidC-typebinary
227 Philosophia ca. 45 Main-belt asteroid
Prometheus $
Saturn XVI (16)
Prometheus 12-26-09a.jpg
ca. 45 156.6 Satellite of Saturn
110 Lydia ca. 45 670 Asteroid
Elara
Jupiter VII
ca. 45 Satellite of JupiterHimalia group
72 Feronia ca. 45 670 Asteroid
Thorondor
Manwë I
ca. 40 Satellite of Manwë
60558 Echeclus
174P/Echeclus
ca. 40 Centaur[52]
S/2000 (90) 1 ca. 40 Asteroid moon of 90 Antiope
71 Niobe ca. 40 610 Asteroid
102 Miriam ca. 40 Asteroid
97 Klotho ca. 40 590 Asteroid
61 Danae ca. 40 Asteroid
Thalassa
Neptune IV
ca. 40 Satellite of Neptune
122 Gerda ca. 40 570 Main-belt asteroidS-type
Pandora$
Saturn XVII (17)
Pandora PIA07632.jpg
ca. 40 135.6 Satellite of Saturn
83 Beatrix ca. 40 560 Main-belt asteroidX-type
32 Pomona ca. 40 Asteroid
Belinda
Uranus XIV (14)
Belinda.gif
ca. 40 Satellite of Uranus
115 Thyra ca. 40 Asteroid
Cressida
Uranus IX
ca. 40 Satellite of Uranus
135 Hertha ca. 40 Asteroid
84 Klio ca. 40 520 Asteroid
80 Sappho ca. 40 Asteroid
Echidna
Typhon I
44±3 Satellite of 42355 Typhon
1001 Gaussia ca. 40 Asteroid
58534 Logos ca. 40 270 Kuiper belt objectcubewanobinary
124 Alkeste ca. 40 470 Main-belt asteroidS-type
55576 Amycus ca. 40 Centaur
25 Phocaea ca. 40 Asteroid
Weywot
Quaoar I
ca. 35 Satellite of Quaoar
8405 Asbolus ca. 35 Centaur
112 Iphigenia ca. 35 Asteroid
Hydra
Pluto III
ca. 35 Satellite of Pluto
Rosalind*
Uranus XIII (13)
ca. 35 250 Satellite of Uranus
Caliban
Uranus XVI (16)
ca. 35 Satellite of Uranus
99 Dike ca. 35 390 Asteroid
66 Maja ca. 35 Asteroid
116 Sirona ca. 35 Main-belt asteroid
44 Nysa ca. 35 370 Main-belt asteroidE-type
10370 Hylonome ca. 35 Centaur
77 Frigga ca. 35 350 Asteroid
55 Pandora ca. 35 Asteroid
133 Cyrene ca. 35 310 Main-belt asteroidS-type
79 Eurynome ca. 35 Asteroid
Zoe
Logos I
ca. 35 Satellite of 58534 Logos
Naiad
Neptune III
Naiad Voyager.png
ca. 35 Satellite of Neptune
43 Ariadne ca. 35 Asteroid
101 Helena ca. 35 300 Asteroid
108 Hecuba ca. 30 390 Asteroid
Desdemona
Uranus X
ca. 30 Satellite of Uranus
Halimede*
Neptune IX
ca. 30 Satellite of Neptune
52975 Cyllarus ca. 30 Centaur
82 Alkmene ca. 30 Asteroid
60 Echo ca. 30 Asteroid
Crantor
83982
ca. 30 Centaur
Comet Hale–Bopp
C/1995 O1
Hale-bopp.jpg
ca. 30 Comet
Pasiphae*
Jupiter VIII
ca. 30 Satellite of Jupiter
7066 Nessus ca. 30 Centaur
Neso
Neptune XIII (13)
ca. 30 Satellite of Neptune
64 Angelina ca. 30 Main-belt asteroidE-type
67 Asia ca. 30 Asteroid
119 Althaea ca. 30 200 Main-belt asteroidS-type
75 Eurydike ca. 30 180 Main-belt asteroidM-type
142 Polana ca. 30 180 Main-belt asteroidF-type
253 Mathilde$
(253) mathilde crop.jpg
26.4 103.3 Main-belt asteroidC-type
52872 Okyrhoe ca. 25 Centaur
Bianca
Uranus VIII
ca. 25 92 Satellite of Uranus
Prospero
Uranus XVIII (18)
ca. 25 85 Satellite of Uranus
Setebos
Uranus XIX (19)
ca. 25 75 Satellite of Uranus
123 Brunhild ca. 25 Main-belt asteroid
4348 Poulydamas ca. 25 AsteroidJupiter Trojan
1000 Piazzia ca. 25 Main-belt asteroid
113 Amalthea ca. 25 100 Main-belt asteroid
Carme*
Jupiter XI
ca. 25 130 Satellite of JupiterCarme group
138 Tolosa ca. 25 99 Main-belt asteroidS-type
126 Velleda ca. 20 94 Main-belt asteroid
73 Klytia ca. 20 92 Asteroid
Sao
Neptune XI (11)
ca. 20 Satellite of Neptune
125 Liberatrix ca. 20 87 Main-belt asteroidM-type
Metis
Jupiter XVI (16)
Metis.jpg
ca. 20 36 Satellite of Jupiter
132 Aethra ca. 20 82 Main-belt asteroidM-type
Ophelia*
Uranus VII
ca. 20 53 Satellite of Uranus
Laomedeia
Neptune XII (12)
ca. 20 Satellite of Neptune
118 Peitho ca. 20 76 Main-belt asteroid
208 Lacrimosa ca. 20 73.9 Main-belt asteroidKoronisS-type
136 Austria ca. 20 68 Main-belt asteroidM-type
131 Vala ca. 20 69 Main-belt asteroid
Cordelia*
Uranus VI
ca. 20 44 Satellite of Uranus
Siarnaq
Saturn XXIX (29)
ca. 20 Satellite of Saturn

Examples of objects between 20 km and 1 km in radius[edit]

Satellites of Mars
Satellites of Jupiter
Satellites of Saturn
Satellites of Uranus
Satellites of Neptune
Satellites of Pluto
Body Image Mean
radius
(km)
Mass
×1015 kg
(Eg)
Type of object
167 Urda ca. 20 66.7 Main-belt asteroidKoronisS-type
Hidalgo
944
ca. 20 Centaur
Sinope*
Jupiter IX
ca. 20 76 Satellite of Jupiter
Psamathe*
Neptune X
ca. 20 37 Satellite of Neptune
29P/Schwassmann–
Wachmann
29P Schwassmann Wachmann.jpg ca. 20 Cometcentaur
Lysithea*
Jupiter X
ca. 20 63 Satellite of JupiterHimalia group
158 Koronis ca. 20 Main-belt asteroidKoronisS-type
Helene
Saturn XII (12)
Dione B
Helene over Saturn.jpg
17.6±0.4 km[53] 25 Satellite of SaturnDione trojan
226 Weringia ca. 15 Main-belt asteroidS-type
433 Eros$
Eros southern hemisphere overview.jpg
ca. 15 66.9 Near-Earth asteroidAmor
Stephano
Uranus XX (20)
ca. 15 22 Satellite of Uranus
Albiorix
Saturn XXVI (26)
ca. 15 Satellite of Saturn
1036 Ganymed ca. 15 33 Near-Earth asteroid
1815 Beethoven ca. 15 Main-belt asteroid
243 Ida
243 Ida large.jpg
15.7[54] 42 Main-belt asteroidKoronisS-typebinary
1655 Comas Solà 15.3±1.1[55] Belt asteroidB-type
Atlas$
Saturn XV (15)
Cassini Atlas N00084634 CL.png
15.1±0.9 km [53] 66 Satellite of Saturn
31824 Elatus ca. 15 Centaur
Perdita
Uranus XXV (25)
ca. 15 13 Satellite of Uranus
Pan$
Saturn XVIII (18)
Pan side view.jpg
14.1±1.3 km[56] 4.95[57] Satellite of Saturn
Linus
Kalliope I
ca. 15 60[58] Moon of 22 Kalliope
Ananke
Jupiter XII (12)
ca. 15 38.2 Satellite of Jupiter
Telesto
Saturn XIII (13) or Tethys B
Telesto cassini closeup.jpg
ca. 10 Satellite of SaturnTethys trojan
Phobos$
Mars I
Phobos colour 2008.jpg
11.267 10.7 Satellite of Mars
Paaliaq
Saturn XX (20)
ca. 10 8.2 Satellite of Saturn
Francisco
Uranus XXII (22)
ca. 10 7.2 Satellite of Uranus
Calypso
Saturn XIV (14) or Tethys C
N00151485 Calypso crop.jpg
ca. 10 Satellite of SaturnTethys trojan
Leda
Jupiter XIII (13)
ca. 10 11 Satellite of JupiterHimalia group
Ferdinand
Uranus XXIV (24)
ca. 10 5.4 Satellite of Uranus
Margaret
Uranus XXIII (23)
ca. 10 5.4 Satellite of Uranus
149 Medusa ca. 10 8 Main-belt asteroid
Romulus
Sylvia I
ca. 10 4 Moon of 87 Sylvia
Ymir
Saturn XIX (19)
ca. 10 Satellite of Saturn
Trinculo
Uranus XXI (21)
ca. 10 3.9 Satellite of Uranus
Cupid
Uranus XXVII (27)
ca. 10 3.8 Satellite of Uranus
S/2004 N 1 ca. 10 Satellite of Neptune
2002 Euler ca. 10 5.5 Asteroid
Adrastea
Jupiter XV (15)
Adrastea.jpg
ca. 10 2 Satellite of Jupiter
Kiviuq
Saturn XXIV (24)
ca. 10 Satellite of Saturn
2000 Herschel ca. 10 Main-belt asteroid[59]
Tarvos
Saturn XXI (21)
Tarvos from Cassini.jpg ca. 10 Satellite of Saturn
S/2006 (624) 1
Hektor I
ca. 10 Moon of 624 Hektor
2685 Masursky
Asteroid 2685Masurky.gif
ca. 10 5–11 Asteroid
Comet Comas Solà 4.2[60] Jupiter-family comet
(65407) 2002 RP120 ca. 5 3.1 Damocloid (retrograde) & possible ejected SDO
Bestla
Saturn XXXIX (39)
ca. 5 Satellite of Saturn
Kerberos
Pluto IV
ca. 10 Satellite of Pluto
Petit-Prince
Eugenia I
ca. 5 1.2 Moon of 45 Eugenia
Deimos$
Mars II
Deimos-MRO.jpg
ca. 5 1.48 Satellite of Mars
951 Gaspra
951 Gaspra.jpg
6.1 ± 0.4 [61] 2–3 Asteroid
Ijiraq
Saturn XXII (22)
ca. 5 Satellite of Saturn
S/2002 (121) 1
Hermione I
ca. 5 1.6 Moon of 121 Hermione
Halley's Comet
Halley's Comet, 1910.JPG
ca. 5 0.03[62] Comet
S/2001 (107) 1
Camilla I
ca. 5 1.5 Moon of 107 Camilla
Styx
Pluto V
ca. 10 Satellite of Pluto
Mab
Uranus XXVI (26)
ca. 5 Satellite of Uranus
Erriapus
Saturn XXVIII (28)
ca. 5 Satellite of Saturn
26858 Misterrogers ca. 5 Asteroid
Callirrhoe
Jupiter XVII (17)
ca. 5 Satellite of Jupiter
Themisto
Jupiter XVIII (18)
ca. 5 0.69 Satellite of Jupiter
Daphnis
Saturn XXXV (35)
Daphnis raw 2010 cropped.jpg
3.9±0.8 0.084[57] Satellite of Saturn
Remus
Sylvia II
ca. 5 0.2 Moon of 87 Sylvia
S/2003 (379) 1
Huenna I
ca. 5 Moon of 379 Huenna
9P/Tempel
PIA02127.jpg
2.8[63] 0.075 Comet
S/2003 (130) 1
Elektra I
ca. 5 0.4 Moon of 130 Elektra
S/2004 (45) 1
Eugenia II
ca. 5 Moon of 45 Eugenia
118401 LINEAR ca. 5 0.23 Main-belt comet
4179 Toutatis
Toutatis.jpg
ca. 5 0.05 Near-Earth asteroid
2867 Šteins
Steins.png
2.65 km[64] AsteroidE-type
3200 Phaethon ca. 5 0.14 AsteroidApolloB-type
3753 Cruithne < 5 .13 Asteroid & quasi-satellite of Earth
5535 Annefrank
Asteroid 5535 Annefrank.jpg
< 5 Asteroid
19P/Borrelly
Comet Borrelly Nucleus.jpg
2.4[65] Comet (Jupiter family)
2P/Encke
Comet Encke.jpg
< 5 Comet
C/1996 B2
Comet Hyakutake
Hyakutake Hubble.gif
< 5 Comet[66]
81P/Wild
Wild 2
Wild2 3.jpg
< 5 Comet
Pallene
Saturn XXXIII (33)
N00163156.jpg
< 5 0.043 Satellite of Saturn
Polydeuces
Saturn XXXIV (34)
Dione C
Polydeuces.jpg
< 5 0.03 Satellite of SaturnDione trojan
17P/Holmes
17pHolmes 071104 eder vga.jpg
< 5 Comet
Comet Churyumov–Gerasimenko
Comet 67P on 19 September 2014 NavCam mosaic.jpg
1.9 Comet
(53319) 1999 JM8
Asteroid 1999 JM8.gif
1.75[67] Asteroid
Methone
Saturn XXXII (32)
Methone PIA14633.jpg
1.6 ± 0.6 0.019 Satellite of Saturn
(285263) 1998 QE2
(285263) 1998 QE2, Goldstone, May 30, 2013.jpg
< 5 Near-Earth asteroid—Binary
4055 Magellan
CCD image of asteroid 4055 Magellan.png
< 5 AsteroidAmorV-type
9969 Braille
PIA01345.jpg
< 5 Asteroid
132524 APL
Asteroid 2002 JF56.jpg
< 5 Asteroid
(6178) 1986 DA < 5 0.002 AsteroidAmorM-type

Examples of objects below 1 km (1000 m) in radius[edit]

Satellites of Jupiter
Satellites of Saturn
Satellites of Uranus
Satellites of Neptune

In the asteroid belt alone there are estimated to be between 1.1 and 1.9 million objects with a radius above 0.5 km,[68] many of which are in the range 0.5–1.0 km. Countless more have a radius below 0.5 km.

Very few objects in this size range have been explored or even imaged. The exceptions are objects that have been visited by a probe, or have passed close enough to Earth to be imaged. Radius is by mean geometric radius. Number of digits not an endorsement of significant figures. Mass scale shifts from × 1015 to 1012 kg, which is 1015 grams (Petagram - Pg).

Body Image Mean
radius
(m)
Mass
×1012 kg
Type of object
1620 Geographos
Geographos.jpg
885[69] 4 Near-Earth asteroidApollo
1862 Apollo 850 5.1 Near-Earth asteroidApolloQ-type
(214869) 2007 PA8 ≈800[70] Near-Earth asteroidApollo
100000 Astronautica ≈800[71] Inner main-belt asteroid[72]
Dactyl
Ida I
Dactyl-HiRes.jpg 700 Moon of 243 Ida
1566 Icarus 700 2.9 Near-Earth asteroidApolloU-type
4769 Castalia 700[73] 1.3 Near-Earth asteroidApollo
(137108) 1999 AN10 650 Near-Earth asteroidApollo
(29075) 1950 DA
1950da color 150.jpg
600 3 Near-Earth asteroidApollo
(66391) 1999 KW4
1999 KW4 animated.gif
600 2.33 Mercury-crosser asteroidAten
46P/Wirtanen 600 Comet
103P/Hartley
Hartley 2
495296main epoxi-1-full full.jpg 570±80 0.3[74] Comet
3908 Nyx 520 5 Near-Earth asteroidAmorV-type
14827 Hypnos 450[75] Comet (dormant)[76]
2062 Aten 450[77] 0.76 Near-Earth asteroidAten
2007 CA19 432 1.2 Near-Earth asteroidApollo
6489 Golevka 350[78] Near-Earth asteroidApollo
25143 Itokawa 346 0.0358 Near-Earth asteroidApollo
2004 XP14 300 Near-Earth asteroidApollo
(144898) 2004 VD17 290 3[79] Near-Earth asteroidApollo
Aegaeon
Saturn LIII (53)
Aegaeon (2008 S1).jpg
250 Satellite of Saturn
2005 YU55[80]
308635
2005YU55-20111107.jpg
180[81] Near-Earth asteroidApolloPHO[82]
4660 Nereus
Nereus.jpg
165[83] Near-Earth asteroidApollo
99942 Apophis 2004MN4 Sormano.gif 162.5[84] 0.05[79] Near-Earth asteroidAtenPHO
S/2009 S 1
PIA11665 moonlet in B Ring cropped.jpg
150 Satellite of Saturn
2010 TK7 150 Earth trojanApollo
2007 TU24
2007 TU24 radar image 20080128.jpg
125[85] Near-Earth asteroidApolloPHO
2002 JE9 100 NEAApolloPHO
2010 XC15 100 NEAApolloPHO
1994 WR12 65[86] 0.002[79] Near-Earth asteroidAten
2009 FD 65[87] 0.0028[87] Near-Earth asteroidApollo
2008 HJ [ 18 [88] 0.000005 [88] Near-Earth asteroid & fast rotator (42 s)[88]
367943 Duende
2012 DA14
Radar-2012DA14-Goldstone.jpg 15 Near-Earth asteroid
1998 KY26 Asteroid 1998 KY26.faces model.jpg 15[89] Near-Earth asteroid & fast rotator (10 m)

Currently most of the objects of mass between 109 kg to 1012 kg (less than 1000 teragrams (Tg)) listed here are near-Earth asteroids. (See also: List of NEAs by distance from Sun.) 1994 WR12 has less mass than the Great Pyramid of Giza, 5.9 × 109 kg.

For more about very small objects in the Solar System, see meteoroid, micrometeoroid, and interplanetary dust cloud. (See also Visited/imaged bodies.)

Surface gravity[edit]

The surface gravity at the equator of a body can in most cases be accurately calculated using Newton's law of universal gravitation and centrifugal force.

The gravitational acceleration at the equator is given by Newton's law of universal gravitation. The formula that follows from this law is:

a_g = G \frac{m}{r^2}

where

ag is the magnitude of the gravitational acceleration
G is the gravitational constant
m is the mass of the celestial body
r is the equatorial radius of the celestial body (if this varies significantly, the mean equatorial radius is used)

The magnitude of the outward acceleration due to centrifugal force is given by

a_c = 4\pi^2\frac{r}{T^2}

where

T is the rotation period of the celestial body

The surface gravity at the equator is then given by

g = a_g - a_c
= \frac{G m}{r^2} - \frac{4\pi^2r}{T^2}

Notes[edit]

Using equatorial radius and assuming body is spherical
Using three radii and assuming body is spheroid
* Radius is known only very approximately
R Radius has been determined by various methods, such as optical (Hubble), thermal (Spitzer), or direct imaging via spacecraft
9 Unknown radius, generic assumed albedo of 0.09
$ Well studied asteroid or moon whose dimensions and mass are very well known. Asteroid sizes and masses taken from James Baer's (Bio) personal website.
M Mass has been determined by perturbation. For asteroids, see James Baer's personal website.
Note: For many of the well-determined moons, radii were taken from the JPL Solar System Dynamics page.
O Radius has been determined by an occultation

References[edit]

  1. ^ Mike Brown. "The Dwarf Planets". CalTech. Archived from the original on 2011-02-12. Retrieved 2008-09-25. 
  2. ^ D. T. Britt; G. J. Consol-magno SJ; W. J. Merline (2006). "Small Body Density and Porosity: New Data, New Insights". Lunar and Planetary Science XXXVII. Retrieved 2008-12-16. 
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Further reading[edit]

External links[edit]