List of gravitationally rounded objects of the Solar System

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Template:Short description Template:Featured list Template:Use dmy dates Template:Contains special characters This is a list of most likely gravitationally rounded objects (GRO) of the Solar System, which are objects that have a rounded, ellipsoidal shape due to their own gravity (but are not necessarily in hydrostatic equilibrium). Apart from the Sun itself, these objects qualify as planets according to common geophysical definitions of that term. The radii of these objects range over three orders of magnitude, from planetary-mass objects like dwarf planets and some moons to the planets and the Sun. This list does not include small Solar System bodies, but it does include a sample of possible planetary-mass objects whose shapes have yet to be determined. The Sun's orbital characteristics are listed in relation to the Galactic Center, while all other objects are listed in order of their distance from the Sun.

Star

Template:Main

The Sun is a G-type main-sequence star. It contains almost 99.9% of all the mass in the Solar System.[1]

Sun[2][3]
Symbol (image)Template:Ref label
Symbol (Unicode)Template:Ref label ☉
Discovery year Prehistoric
Mean distance
from the Galactic Center 		km
light years 		≈ 2.5Template:E
≈ 26,000
Mean radius km
:ETemplate:Ref label 		695,508
109.3
Surface area km2
:ETemplate:Ref label 		6.0877Template:E
11,990
Volume km3
:ETemplate:Ref label 		1.4122Template:E
1,300,000
Mass kg
:ETemplate:Ref label 		1.9855Template:E
332,978.9
Gravitational parameter m3/s2 1.327×1020
Density g/cm3 1.409
Equatorial gravity m/s2
g 		274.0
27.94
Escape velocity km/s 617.7
Rotation period daysTemplate:Ref label 25.38
Orbital period about Galactic Center[4] million years 225–250
Mean orbital speed[4] km/s ≈ 220
Axial tiltTemplate:Ref label to the ecliptic deg. 7.25
Axial tiltTemplate:Ref label to the galactic plane deg. 67.23
Mean surface temperature K 5,778
Mean coronal temperature[5] K 1–2Template:E
Photospheric composition H, He, O, C, Fe, S

Planets

Template:Main

In 2006, the International Astronomical Union (IAU) defined a planet as a body in orbit around the Sun that was large enough to have achieved hydrostatic equilibrium and to have "cleared the neighbourhood around its orbit".[6] The practical meaning of "cleared the neighborhood" is that a planet is comparatively massive enough for its gravitation to control the orbits of all objects in its vicinity. In practice, the term "hydrostatic equilibrium" is interpreted loosely. Mercury is round but not actually in hydrostatic equilibrium, but it is universally regarded as a planet nonetheless.[7]

According to the IAU's explicit count, there are eight planets in the Solar System; four terrestrial planets (Mercury, Venus, Earth, and Mars) and four giant planets, which can be divided further into two gas giants (Jupiter and Saturn) and two ice giants (Uranus and Neptune). When excluding the Sun, the four giant planets account for more than 99% of the mass of the Solar System.

Template:Clear right

Key
* Terrestrial planet
° Gas giant
× Ice giant
  *Mercury[8][9][10] *Venus[11][12][10] *Earth[13][14][10] *Mars[15][16][10] °Jupiter[17][18][10] °Saturn[19][20][10] ×Uranus[21][22] ×Neptune[23][24][10]
SymbolTemplate:Ref label or
Symbol (Unicode)Template:Ref label ☿ ♀ 🜨 ♂ ♃ ♄ ⛢ or ♅ ♆
Discovery year Prehistoric Prehistoric Prehistoric Prehistoric Prehistoric Prehistoric 1781 1846
Mean distance
from the Sun 		km
AU 		57,909,175
0.38709893 		108,208,930
0.72333199 		149,597,890
1.00000011 		227,936,640
1.52366231 		778,412,010
5.20336301 		1,426,725,400
9.53707032 		2,870,972,200
19.19126393 		4,498,252,900
30.06896348
Equatorial radius km
:ETemplate:Ref label 		2,440.53
0.3826 		6,051.8
0.9488 		6,378.1366
1 		3,396.19
0.53247 		71,492
11.209 		60,268
9.449 		25,559
4.007 		24,764
3.883
Surface area km2
:ETemplate:Ref label 		75,000,000
0.1471 		460,000,000
0.9020 		510,000,000
1 		140,000,000
0.2745 		64,000,000,000
125.5 		44,000,000,000
86.27 		8,100,000,000
15.88 		7,700,000,000
15.10
Volume km3
:ETemplate:Ref label 		6.083Template:E
0.056 		9.28Template:E
0.857 		1.083Template:E
1 		1.6318Template:E
0.151 		1.431Template:E
1,321.3 		8.27Template:E
763.62 		6.834Template:E
63.102 		6.254Template:E
57.747
Mass kg
:ETemplate:Ref label 		3.302Template:E
0.055 		4.8690Template:E
0.815 		5.972Template:E
1 		6.4191Template:E
0.107 		1.8987Template:E
318 		5.6851Template:E
95 		8.6849Template:E
14.5 		1.0244Template:E
17
Gravitational parameter m3/s2 2.203×1013 3.249×1014 3.986×1014 4.283×1013 1.267×1017 3.793×1016 5.794×1015 6.837×1015
Density g/cm3 5.43 5.24 5.52 3.940 1.33 0.70 1.30 1.76
Equatorial gravity m/s2
g 		3.70
0.377 		8.87
0.904 		9.8
1.00 		3.71
0.378 		24.79
2.528 		10.44
1.065 		8.87
0.904 		11.15
1.137
Escape velocity km/s 4.25 10.36 11.18 5.02 59.54 35.49 21.29 23.71
Rotation periodTemplate:Ref label days 58.646225 243.0187 0.99726968 1.02595675 0.41354 0.44401 0.71833 0.67125
Orbital periodTemplate:Ref label days
years 		87.969
0.2408467 		224.701
0.61519726 		365.256363
1.0000174 		686.971
1.8808476 		4,332.59
11.862615 		10,759.22
29.447498 		30,688.5
84.016846 		60,182
164.79132
Mean orbital speed km/s 47.8725 35.0214 29.7859 24.1309 13.0697 9.6724 6.8352 5.4778
Eccentricity 0.20563069 0.00677323 0.01671022 0.09341233 0.04839266 0.05415060 0.04716771 0.00858587
InclinationTemplate:Ref label deg. 7.00 3.39 0[13] 1.85 1.31 2.48 0.76 1.77
Axial tiltTemplate:Ref label deg. 0.0 177.3Template:Ref label 23.44 25.19 3.12 26.73 97.86Template:Ref label 28.32
Mean surface temperature K 440–100 730 287 227 152 Template:Ref label 134 Template:Ref label 76 Template:Ref label 73 Template:Ref label
Mean air temperatureTemplate:Ref label K 288 165 135 76 73
Atmospheric composition He,  Na+
K+  		CO2, N2, SO2 N2, O2, Ar, CO2 CO2, N2
Ar 		H2, He H2, He H2, He
CH4 		H2, He
CH4
Number of known moonsTemplate:Ref label 0 0 1 2 95 146 28 16
Rings? No No No No Yes Yes Yes Yes
Planetary discriminantTemplate:Ref labelTemplate:Ref label 9.1Template:E 1.35Template:E 1.7Template:E 1.8Template:E 6.25Template:E 1.9Template:E 2.9Template:E 2.4Template:E

Dwarf planets

Template:Main Template:See also

Dwarf planets are bodies orbiting the Sun that are massive and warm enough to have achieved hydrostatic equilibrium, but have not cleared their neighbourhoods of similar objects. Since 2008, there have been five dwarf planets recognized by the IAU, although only Pluto has actually been confirmed to be in hydrostatic equilibrium[25] (Ceres is close to equilibrium, though some anomalies remain unexplained).[26] Ceres orbits in the asteroid belt, between Mars and Jupiter. The others all orbit beyond Neptune.

Key
† Asteroid belt
‡ Kuiper belt
§ Scattered disc
× Sednoid
†Template:Dwarfplanet[27] ‡Template:Dwarfplanet[28][29] ‡Template:Dwarfplanet[30][31][32] ‡Template:Dwarfplanet[33][34] §Template:Dwarfplanet[35]
SymbolTemplate:Ref label or
Symbol (Unicode)Template:Ref label ⚳ ♇ or ⯓ 🝻 🝼 ⯰
Minor planet number 1 134340 136108 136472 136199
Discovery year 1801 1930 2004 2005 2005
Mean distance
from the Sun 		km
AU 		413,700,000
2.766 		5,906,380,000
39.482 		6,484,000,000
43.335 		6,850,000,000
45.792 		10,210,000,000
67.668
Mean radius km
:ETemplate:Ref label 		473
0.0742 		1,188.3[10]
0.186 		816
Template:Small
0.13[36][37] 		715
0.11[38] 		1,163
0.18[39]
Volume km3
:ETemplate:Ref label 		4.21Template:E
0.00039Template:Ref label 		6.99Template:E
0.0065 		1.98Template:E
0.0018 		1.7Template:E
0.0016Template:Ref label 		6.59Template:E
0.0061Template:Ref label
Surface area km2
:ETemplate:Ref label 		2,770,000
0.0054Template:Ref label 		17,700,000
0.035 		8,140,000
0.016Template:Ref label 		6,900,000
0.0135Template:Ref label 		17,000,000
0.0333Template:Ref label
Mass kg
:ETemplate:Ref label 		9.39Template:E
0.00016 		1.30Template:E
0.0022 		4.01 ± 0.04Template:E
0.0007[40] 		≈ 3.1Template:E
0.0005 		1.65Template:E
0.0028
Gravitational parameter m3/s2 6.263 × 1010 8.710 × 1011 2.674 × 1011 2.069 × 1011 1.108 × 1012
Density g/cm3 2.16 1.87 2.02[36] 2.03 2.43
Equatorial gravity m/s2
g 		0.27Template:Ref label
0.028 		0.62
0.063 		0.63Template:Ref label
0.064 		0.40
0.041 		0.82Template:Ref label
0.084
Escape velocity km/sTemplate:Ref label 0.51 1.21 0.91 0.54 1.37
Rotation periodTemplate:Ref label days 0.3781 6.3872 0.1631 0.9511 15.7859
Orbital periodTemplate:Ref label years 4.599 247.9 283.8 306.2 559
Mean orbital speed km/s 17.882 4.75 4.48Template:Ref label 4.40Template:Ref label 3.44Template:Ref label
Eccentricity 0.080 0.249 0.195 0.161 0.436
InclinationTemplate:Ref label deg. 10.59 17.14 28.21 28.98 44.04
Axial tiltTemplate:Ref label deg. 4 119.6Template:Ref label ≈ 126Template:Ref label ? ≈ 78
Mean surface temperatureTemplate:Ref label K 167[41] 40[42] <50[43] 30 30
Atmospheric composition H2O N2, CH4, CO ? N2, CH4[44] N2, CH4[45]
Number of known moonsTemplate:Ref label 0 5 2[46] 1[47] 1[48]
Rings? No No Yes ? ?
Planetary discriminantTemplate:Ref labelTemplate:Ref label 0.33 0.077 0.023 0.02 0.10

Astronomers usually refer to solid bodies such as Ceres as dwarf planets, even if they are not strictly in hydrostatic equilibrium. They generally agree that several other trans-Neptunian objects (TNOs) may be large enough to be dwarf planets, given current uncertainties. However, there has been disagreement on the required size. Early speculations were based on the small moons of the giant planets, which attain roundness around a threshold of 200 km radius.[49] However, these moons are at higher temperatures than TNOs and are icier than TNOs are likely to be. Estimates from an IAU question-and-answer press release from 2006, giving 800 km radius and Template:Val mass as cut-offs that normally would be enough for hydrostatic equilibrium, while stating that observation would be needed to determine the status of borderline cases.[50] Many TNOs in the 200–500 km radius range are dark and low-density bodies, which suggests that they retain internal porosity from their formation, and hence are not planetary bodies (as planetary bodies have sufficient gravitation to collapse out such porosity).[51]

In 2023, Emery et al. wrote that near-infrared spectroscopy by the James Webb Space Telescope (JWST) in 2022 suggests that Sedna, Gonggong, and Quaoar underwent internal melting, differentiation, and chemical evolution, like the larger dwarf planets Pluto, Eris, Haumea, and Makemake, but unlike "all smaller KBOs". This is because light hydrocarbons are present on their surfaces (e.g. ethane, acetylene, and ethylene), which implies that methane is continuously being resupplied, and that methane would likely come from internal geochemistry. On the other hand, the surfaces of Sedna, Gonggong, and Quaoar have low abundances of CO and CO2, similar to Pluto, Eris, and Makemake, but in contrast to smaller bodies. This suggests that the threshold for dwarf planethood in the trans-Neptunian region is around 500 km radius.[52]

In 2024, Kiss et al. found that Quaoar has an ellipsoidal shape incompatible with hydrostatic equilibrium for its current spin. They hypothesised that Quaoar originally had a rapid rotation and was in hydrostatic equilibrium, but that its shape became "frozen in" and did not change as it spun down due to tidal forces from its moon Weywot.[53] If so, this would resemble the situation of Saturn's moon Iapetus, which is too oblate for its current spin.[54][55] Iapetus is generally still considered a planetary-mass moon nonetheless,[56] though not always.[57]

The table below gives Orcus, Quaoar, Gonggong, and Sedna as additional consensus dwarf planets; slightly smaller Salacia, which is larger than 400 km radius, has been included as a borderline case for comparison, (and is therefore italicized).

‡Orcus[58] ‡Salacia[59] ‡Quaoar[60] §Gonggong[61] ×Sedna[62]
SymbolTemplate:Ref label
Symbol (Unicode)Template:Ref label 🝿 🝾 🝽 ⯲
Minor-planet number 90482 120347 50000 225088 90377
Discovery year 2004 2004 2002 2007 2003
Semi-major axis km
AU 		5,896,946,000
39.419 		6,310,600,000
42.18 		6,535,930,000
43.69 		10,072,433,340
67.33 		78,668,000,000
525.86
Mean radiusTemplate:Ref label km
:ETemplate:Ref label 		458.5[63]
0.0720 		423[64]
0.0664 		555[65]
0.0871 		615[66]
0.0982 		497.5[67]
0.0780
Surface areaTemplate:Ref label km2
:ETemplate:Ref label 		2,641,700
0.005179 		2,248,500
0.004408 		3,870,800
0.007589 		4,932,300
0.009671 		3,110,200
0.006098
VolumeTemplate:Ref label km3
:ETemplate:Ref label 		403,744,500
0.000373 		317,036,800
0.000396 		716,089,900
0.000661 		1,030,034,600
0.000951 		515,784,000
0.000476
MassTemplate:Ref label kg
:ETemplate:Ref label 		5.48Template:E[68]
0.0001 		4.9Template:E[64]
0.0001 		1.20Template:E[69]
0.0002 		1.75Template:E[66]
0.0003 		?
DensityTemplate:Ref label g/cm3 Template:Val[68] Template:Val[64] ≈ Template:Val Template:Val ?
Equatorial gravityTemplate:Ref label m/s2
g 		Template:Gr
0.017 		Template:Gr
0.018 		Template:Gr
0.025 		Template:Gr
0.029 		?
Escape velocityTemplate:Ref label km/s Template:V2 Template:V2 Template:V2 Template:V2 ?
Rotation periodTemplate:Ref label days 9.54?[68] ? 0.7367[69] 0.9333 0.4280[70]
Orbital periodTemplate:Ref label years 247.49 273.98 287.97 552.52 12,059
Mean orbital speed km/s 4.68 4.57 4.52 3.63 1.04
Eccentricity 0.226 0.106 0.038 0.506 0.855
InclinationTemplate:Ref label deg. 20.59 23.92 7.99 30.74 11.93
Axial tiltTemplate:Ref label deg. ? ? 13.6[69] or 14.0[71] ? ?
Mean surface temperatureTemplate:Ref label K ≈ 42 ≈ 43 ≈ 41 ≈ 30 ≈ 12
Number of known moons 1[72] 1 1[73] 1 0
Rings? ? ? Yes[69] ? ?
Planetary discriminantTemplate:Ref labelTemplate:Ref label 0.003 <0.1 0.0015 <0.1 ?Template:Ref label
Absolute magnitude (H) 2.3 4.1 2.71 1.8 1.5

As for objects in the asteroid belt, none are generally agreed as dwarf planets today among astronomers other than Ceres. The second- through fifth-largest asteroids have been discussed as candidates. Vesta (radius Template:Val), the second-largest asteroid, appears to have a differentiated interior and therefore likely was once a dwarf planet, but it is no longer very round today.[74] Pallas (radius Template:Val), the third-largest asteroid, appears never to have completed differentiation and likewise has an irregular shape. Vesta and Pallas are nonetheless sometimes considered small terrestrial planets anyway by sources preferring a geophysical definition, because they do share similarities to the rocky planets of the inner solar system.[56] The fourth-largest asteroid, Hygiea (radius Template:Val), is icy. The question remains open if it is currently in hydrostatic equilibrium: while Hygiea is round today, it was probably previously catastrophically disrupted and today might be just a gravitational aggregate of the pieces.[75] The fifth-largest asteroid, Interamnia (radius Template:Val), is icy and has a shape consistent with hydrostatic equilibrium for a slightly shorter rotation period than it now has.[76]

Satellites

Template:Main Template:Further

There are at least 19 natural satellites in the Solar System that are known to be massive enough to be close to hydrostatic equilibrium: seven of Saturn, five of Uranus, four of Jupiter, and one each of Earth, Neptune, and Pluto. Alan Stern calls these satellite planets, although the term major moon is more common. The smallest natural satellite that is gravitationally rounded is Saturn I Mimas (radius Template:Val). This is smaller than the largest natural satellite that is known not to be gravitationally rounded, Neptune VIII Proteus (radius Template:Val).

Several of these were once in equilibrium but are no longer: these include Earth's moon[77] and all of the moons listed for Saturn apart from Titan and Rhea.[55] The status of Callisto, Titan, and Rhea is uncertain, as is that of the moons of Uranus, Pluto[25] and Eris.[51] The other large moons (Io, Europa, Ganymede, and Triton) are generally believed to still be in equilibrium today. Other moons that were once in equilibrium but are no longer very round, such as Saturn IX Phoebe (radius Template:Val), are not included. In addition to not being in equilibrium, Mimas and Tethys have very low densities and it has been suggested that they may have non-negligible internal porosity,[78][79] in which case they would not be satellite planets.

The moons of the trans-Neptunian objects (other than Charon) have not been included, because they appear to follow the normal situation for TNOs rather than the moons of Saturn and Uranus, and become solid at a larger size (900–1000 km diameter, rather than 400 km as for the moons of Saturn and Uranus). Eris I Dysnomia and Orcus I Vanth, though larger than Mimas, are dark bodies in the size range that should allow for internal porosity, and in the case of Dysnomia a low density is known.[51]

Satellites are listed first in order from the Sun, and second in order from their parent body. For the round moons, this mostly matches the Roman numeral designations, with the exceptions of Iapetus and the Uranian system. This is because the Roman numeral designations originally reflected distance from the parent planet and were updated for each new discovery until 1851, but by 1892, the numbering system for the then-known satellites had become "frozen" and from then on followed order of discovery. Thus Miranda (discovered 1948) is Uranus V despite being the innermost of Uranus' five round satellites. The missing Saturn VII is Hyperion, which is not large enough to be round (mean radius Template:Val).

Key
🜨 Satellite of Earth
♃ Satellite of Jupiter
♄ Satellite of Saturn
⛢ Satellite of Uranus
♆ Satellite of Neptune
♇ Satellite of Pluto
🜨Moon[80] ♃Io[81] ♃Europa[82] ♃Ganymede[83] ♃Callisto[84] ♄MimasTemplate:Ref label ♄EnceladusTemplate:Ref label ♄TethysTemplate:Ref label ♄DioneTemplate:Ref label ♄RheaTemplate:Ref label
Roman numeral designation Earth I Jupiter I Jupiter II Jupiter III Jupiter IV Saturn I Saturn II Saturn III Saturn IV Saturn V
SymbolTemplate:Ref label ☾ JI JII JIII JIV SI SII SIII SIV SV
Symbol (Unicode)Template:Ref label ☾
Discovery year Prehistoric 1610 1610 1610 1610 1789 1789 1684 1684 1672
Mean distance
from primary 		km 384,399 421,600 670,900 1,070,400 1,882,700 185,520 237,948 294,619 377,396 527,108
Mean radius km
:ETemplate:Ref label 		1,737.1
0.272 		1,815
0.285 		1,569
0.246 		2,634.1
0.413 		2,410.3
0.378 		198.30
0.031 		252.1
0.04 		533
0.084 		561.7
0.088 		764.3
0.12
Surface areaTemplate:Ref label 1Template:E km2 37.93 41.910 30.9 87.0 73 0.49 0.799 3.57 3.965 7.337
VolumeTemplate:Ref label 1Template:E km3 22 25.3 15.9 76 59 0.033 0.067 0.63 0.8 1.9
Mass 1Template:E kg 7.3477 8.94 4.80 14.819 10.758 0.00375 0.0108 0.06174 0.1095 0.2306
DensityTemplate:Ref label g/cm3 3.3464 3.528 3.01 1.936 1.83 1.15 1.61 0.98 1.48 1.23
Equatorial gravityTemplate:Ref label m/s2
g 		1.622
0.1654 		1.796
0.1831 		1.314
0.1340 		1.428
0.1456 		1.235
0.1259 		0.0636
0.00649 		0.111
0.0113 		0.145
0.0148 		0.231
0.0236 		0.264
0.0269
Escape velocityTemplate:Ref label km/s 2.38 2.56 2.025 2.741 2.440 0.159 0.239 0.393 0.510 0.635
Rotation period daysTemplate:Ref label 27.321582
(sync)Template:Ref label 		1.7691378
(sync) 		3.551181
(sync) 		7.154553
(sync) 		16.68902
(sync) 		0.942422
(sync) 		1.370218
(sync) 		1.887802
(sync) 		2.736915
(sync) 		4.518212
(sync)
Orbital period about primary daysTemplate:Ref label 27.32158 1.769138 3.551181 7.154553 16.68902 0.942422 1.370218 1.887802 2.736915 4.518212
Mean orbital speedTemplate:Ref label km/s 1.022 17.34 13.740 10.880 8.204 14.32 12.63 11.35 10.03 8.48
Eccentricity 0.0549 0.0041 0.009 0.0013 0.0074 0.0202 0.0047 0.02 0.002 0.001
Inclination to primary's equator deg. 18.29–28.58 0.04 0.47 1.85 0.2 1.51 0.02 1.51 0.019 0.345
Axial tiltTemplate:Ref labelTemplate:Ref label deg. 6.68 0.000405
± 0.00076[85] 		0.0965
± 0.0069[85] 		0.155
± 0.065[85] 		≈ 0–2[85]Template:Ref label ≈ 0 ≈ 0 ≈ 0 ≈ 0 ≈ 0
Mean surface temperatureTemplate:Ref label K 220 130 102 110[86] 134 64 75 64 87 76
Atmospheric composition Ar, He
Na, K, H 		SO2[87] O2[88] O2[89] O2, CO2[90] H2O, N2
CO2, CH4[91]
♄TitanTemplate:Ref label ♄IapetusTemplate:Ref label ⛢MirandaTemplate:Ref label ⛢ArielTemplate:Ref label ⛢UmbrielTemplate:Ref label ⛢TitaniaTemplate:Ref label ⛢OberonTemplate:Ref label ♆Triton[92] ♇Charon[28]
Roman numeral designation Saturn VI Saturn VIII Uranus V Uranus I Uranus II Uranus III Uranus IV Neptune I Pluto I
Symbol SVI SVIII UV UI UII UIII UIV NI PI
Discovery year 1655 1671 1948 1851 1851 1787 1787 1846 1978
Mean distance
from primary 		km 1,221,870 3,560,820 129,390 190,900 266,000 436,300 583,519 354,759 17,536
Mean radius km
:ETemplate:Ref label 		2,576
0.404 		735.60
0.115 		235.8
0.037 		578.9
0.091 		584.7
0.092 		788.9
0.124 		761.4
0.119 		1,353.4
0.212 		603.5
0.095
Surface areaTemplate:Ref label 1Template:E km2 83.0 6.7 0.70 4.211 4.296 7.82 7.285 23.018 4.580
VolumeTemplate:Ref label 1Template:E km3 71.6 1.67 0.055 0.81 0.84 2.06 1.85 10 0.92
Mass 1Template:E kg 13.452 0.18053 0.00659 0.135 0.12 0.35 0.3014 2.14 0.152
DensityTemplate:Ref label g/cm3 1.88 1.08 1.20 1.67 1.40 1.72 1.63 2.061 1.65
Equatorial gravityTemplate:Ref label m/s2
g 		1.35
0.138 		0.22
0.022 		0.08
0.008 		0.27
0.028 		0.23
0.023 		0.39
0.040 		0.35
0.036 		0.78
0.080 		0.28
0.029
Escape velocityTemplate:Ref label km/s 2.64 0.57 0.19 0.56 0.52 0.77 0.73 1.46 0.58
Rotation period daysTemplate:Ref label 15.945
(sync)Template:Ref label 		79.322
(sync) 		1.414
(sync) 		2.52
(sync) 		4.144
(sync) 		8.706
(sync) 		13.46
(sync) 		5.877
(sync) 		6.387
(sync)
Orbital period about primary days 15.945 79.322 1.4135 2.520 4.144 8.706 13.46 5.877 6.387
Mean orbital speedTemplate:Ref label km/s 5.57 3.265 6.657 5.50898 4.66797 3.644 3.152 4.39 0.2
Eccentricity 0.0288 0.0286 0.0013 0.0012 0.005 0.0011 0.0014 0.00002 0.0022
Inclination to primary's equator deg. 0.33 14.72 4.22 0.31 0.36 0.14 0.10 157Template:Ref label 0.001
Axial tiltTemplate:Ref labelTemplate:Ref label deg. ≈ 0.3[93] ≈ 0 ≈ 0 ≈ 0 ≈ 0 ≈ 0 ≈ 0 ≈ 0.7[94] ≈ 0
Mean surface temperatureTemplate:Ref label K 93.7[95] 130 59 58 61 60 61 38[96] 53
Atmospheric composition N2, CH4[97] N2, CH4[98]

See also

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Notes

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Unless otherwise citedTemplate:Ref label

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Manual calculations (unless otherwise cited)

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Individual calculations

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Other notes

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References

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