<P> It was once expected that any icy body larger than approximately 200 km in radius was likely to be in hydrostatic equilibrium (HE). However, Rhea is the smallest body where detailed measurements have been made and are consistent with hydrostatic equilibrium, whereas Iapetus is the largest determined not to be in hydrostatic equilibrium, bracketing a radius of 750 km . </P> <P> For simplicity and comparative purposes, the values are manually calculated assuming a sphericity of 1 . 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 giant planets, the "radius" is the point at which the atmosphere reaches 1 bar of atmospheric pressure . The radius of Saturn's main rings is 136,775 km . </P> <Table> <Tr> <Th> Body </Th> <Th> Image </Th> <Th_colspan="2"> Radius </Th> <Th_colspan="2"> Volume </Th> <Th_colspan="2"> Mass </Th> <Th> Density </Th> <Th_colspan="2"> Gravity </Th> <Th> Type </Th> <Th> Shape </Th> <Th> #</Th> </Tr> <Tr> <Th> (km) </Th> <Th> (R) </Th> <Th> (10 km) </Th> <Th> (V) </Th> <Th> (10 kg) </Th> <Th> (M) </Th> <Th> (g / cm) </Th> <Th> (m / s) </Th> <Th> (⊕) </Th> </Tr> <Tr> <Td> Sun </Td> <Td> </Td> <Td> 7005696342000000000 ♠ 696 342 ± 65 </Td> <Td> 109.3 </Td> <Td> 1,414,300,000 </Td> <Td> 1,305,700 </Td> <Td> 1,988,550,000 </Td> <Td> 333,000 </Td> <Td> 1.408 </Td> <Td> 274.0 </Td> <Td> 27.94 </Td> <Td> star </Td> <Td> round (HE) </Td> <Td> </Td> </Tr> <Tr> <Td> Jupiter </Td> <Td> </Td> <Td> 7004699110000000000 ♠ 69 911 ± 6 </Td> <Td> 10.97 </Td> <Td> 1,431,280 </Td> <Td> 1,321 </Td> <Td> 1,898,600 </Td> <Td> 317.83 </Td> <Td> 1.326 </Td> <Td> 24.79 </Td> <Td> 2.528 </Td> <Td> planet (gas giant); has rings </Td> <Td> round (HE) </Td> <Td> </Td> </Tr> <Tr> <Td> Saturn </Td> <Td> </Td> <Td> 7004582320000000000 ♠ 58 232 ± 6 (w / o rings) </Td> <Td> 9.140 </Td> <Td> 827,130 </Td> <Td> 764 </Td> <Td> 568,460 </Td> <Td> 95.162 </Td> <Td> 0.687 </Td> <Td> 10.445 </Td> <Td> 1.065 </Td> <Td> planet (gas giant); has rings </Td> <Td> round (HE) </Td> <Td> </Td> </Tr> <Tr> <Td> Uranus </Td> <Td> </Td> <Td> 7004253620000000000 ♠ 25 362 ± 7 </Td> <Td> 3.981 </Td> <Td> 68,340 </Td> <Td> 63.1 </Td> <Td> 86,832 </Td> <Td> 14.536 </Td> <Td> 1.27 </Td> <Td> 8.69 </Td> <Td> 0.90 </Td> <Td> planet (ice giant); has rings </Td> <Td> round (HE) </Td> <Td> </Td> </Tr> <Tr> <Td> Neptune </Td> <Td> </Td> <Td> 7004246220000000000 ♠ 24 622 ± 19 </Td> <Td> 3.865 </Td> <Td> 62,540 </Td> <Td> 57.7 </Td> <Td> 102,430 </Td> <Td> 17.147 </Td> <Td> 1.638 </Td> <Td> 11.15 </Td> <Td> 1.137 </Td> <Td> planet (ice giant); has rings </Td> <Td> round (HE) </Td> <Td> 5 </Td> </Tr> <Tr> <Td> Earth </Td> <Td> </Td> <Td> 7003637100000000000 ♠ 6371. 0 ± 0.01 </Td> <Td> </Td> <Td> 1,083.21 </Td> <Td> </Td> <Td> 5,973.6 </Td> <Td> </Td> <Td> 5.514 </Td> <Td> 9.80665 </Td> <Td> </Td> <Td> planet (terrestrial) </Td> <Td> round (HE) </Td> <Td> 6 </Td> </Tr> <Tr> <Td> Venus </Td> <Td> </Td> <Td> 7003605180000000000 ♠ 6051. 8 ± 1.0 (w / o gas) </Td> <Td> 0.9499 </Td> <Td> 928.43 </Td> <Td> 0.857 </Td> <Td> 4,868.5 </Td> <Td> 0.815 </Td> <Td> 5.243 </Td> <Td> 8.872 </Td> <Td> 0.905 </Td> <Td> planet (terrestrial) </Td> <Td> round (HE) </Td> <Td> 7 </Td> </Tr> <Tr> <Td> Mars </Td> <Td> </Td> <Td> 7003338950000000000 ♠ 3389. 5 ± 0.2 </Td> <Td> 0.5320 </Td> <Td> 163.18 </Td> <Td> 0.151 </Td> <Td> 641.85 </Td> <Td> 0.107 </Td> <Td> 3.9335 ± 0.0004 </Td> <Td> 3.7 </Td> <Td> 0.38 </Td> <Td> planet (terrestrial) </Td> <Td> round (HE) </Td> <Td> 8 </Td> </Tr> <Tr> <Td> Ganymede Jupiter III </Td> <Td> </Td> <Td> 7003263410000000000 ♠ 2634. 1 ± 0.3 </Td> <Td> 0.4135 </Td> <Td> 76.30 </Td> <Td> 0.0704 </Td> <Td> 148.2 </Td> <Td> 0.0248 </Td> <Td> 1.936 </Td> <Td> 1.428 </Td> <Td> 0.15 </Td> <Td> moon of Jupiter </Td> <Td> round (HE) </Td> <Td> 9 </Td> </Tr> <Tr> <Td> Titan Saturn VI </Td> <Td> </Td> <Td> 7003257600000000000 ♠ 2576 ± 2 (w / o gas) </Td> <Td> 0.4043 </Td> <Td> 71.52 </Td> <Td> 0.0660 </Td> <Td> 134.5 </Td> <Td> 0.0225 </Td> <Td> 1.8798 ± 0.0044 </Td> <Td> 1.354 </Td> <Td> 0.14 </Td> <Td> moon of Saturn </Td> <Td> round (HE) </Td> <Td> 10 </Td> </Tr> <Tr> <Td> Mercury </Td> <Td> </Td> <Td> 7003243969999999999 ♠ 2439. 7 ± 1.0 </Td> <Td> 0.3829 </Td> <Td> 60.83 </Td> <Td> 0.0562 </Td> <Td> 330.2 </Td> <Td> 0.0553 </Td> <Td> 5.427 </Td> <Td> 3.7 </Td> <Td> 0.38 </Td> <Td> planet (terrestrial) </Td> <Td> round (HE) </Td> <Td> 11 </Td> </Tr> <Tr> <Td> Callisto Jupiter IV </Td> <Td> </Td> <Td> 7003241030000000000 ♠ 2410. 3 ± 1.5 </Td> <Td> 0.3783 </Td> <Td> 58.65 </Td> <Td> 0.0541 </Td> <Td> 107.6 </Td> <Td> 0.018 </Td> <Td> 1.8344 ± 0.0034 </Td> <Td> 1.23603 </Td> <Td> 0.126 </Td> <Td> moon of Jupiter </Td> <Td> round (HE) </Td> <Td> 12 </Td> </Tr> <Tr> <Td> Io Jupiter I </Td> <Td> </Td> <Td> 7003182160000000000 ♠ 1821. 6 ± 0.5 </Td> <Td> 0.2859 </Td> <Td> 25.32 </Td> <Td> 0.0234 </Td> <Td> 89.3 </Td> <Td> 0.015 </Td> <Td> 3.528 ± 0.006 </Td> <Td> 1.797 </Td> <Td> 0.183 </Td> <Td> moon of Jupiter </Td> <Td> round (HE) </Td> <Td> 13 </Td> </Tr> <Tr> <Td> Moon Earth I </Td> <Td> </Td> <Td> 7003173710000000000 ♠ 1737. 1 </Td> <Td> 0.2727 </Td> <Td> 21.958 </Td> <Td> 0.0203 </Td> <Td> 73.5 </Td> <Td> 0.0123 </Td> <Td> 3.3464 </Td> <Td> 1.625 </Td> <Td> 0.166 </Td> <Td> moon of Earth </Td> <Td> round (HE) </Td> <Td> 14 </Td> </Tr> <Tr> <Td> Europa Jupiter II </Td> <Td> </Td> <Td> 7003156080000000000 ♠ 1560. 8 ± 0.5 </Td> <Td> 0.2450 </Td> <Td> 15.93 </Td> <Td> 0.0147 </Td> <Td> 48 </Td> <Td> 0.008035 </Td> <Td> 3.013 ± 0.005 </Td> <Td> 1.316 </Td> <Td> 0.134 </Td> <Td> moon of Jupiter </Td> <Td> round (HE) </Td> <Td> 15 </Td> </Tr> <Tr> <Td> Triton Neptune I </Td> <Td> </Td> <Td> 7003135340000000000 ♠ 1353. 4 ± 0.9 </Td> <Td> 0.2124 </Td> <Td> 10.38 </Td> <Td> 0.0096 </Td> <Td> 21.5 </Td> <Td> 0.003599 </Td> <Td> 2.061 </Td> <Td> 0.782 </Td> <Td> 0.0797 </Td> <Td> moon of Neptune </Td> <Td> round (HE) </Td> <Td> 16 </Td> </Tr> <Tr> <Td> Pluto 134340 </Td> <Td> </Td> <Td> 7003118600000000000 ♠ 1186 ± 2 </Td> <Td> 0.186 </Td> <Td> 6.95 </Td> <Td> 0.0064 </Td> <Td> 13.105 </Td> <Td> 0.0022 </Td> <Td> 1.87 ± 0.02 </Td> <Td> 0.61 </Td> <Td> 0.062 </Td> <Td> dwarf planet; plutino; multiple </Td> <Td> round (HE) </Td> <Td> 17 </Td> </Tr> <Tr> <Td> Eris 136199 </Td> <Td> </Td> <Td> 7003116300000000000 ♠ 1163 ± 6 </Td> <Td> 0.1825 </Td> <Td> 6.59 </Td> <Td> 0.006 </Td> <Td> 16.7 </Td> <Td> 0.0028 </Td> <Td> 2.52 ± 0.05 </Td> <Td> 0.659 </Td> <Td> 0.0672 </Td> <Td> dwarf planet; SDO; binary </Td> <Td> round (HE) </Td> <Td> 18 </Td> </Tr> <Tr> <Td> Titania Uranus III </Td> <Td> </Td> <Td> 7002788400000000000 ♠ 788.4 ± 0.6 </Td> <Td> 0.1237 </Td> <Td> 2.06 </Td> <Td> 0.0019 </Td> <Td> 3.526 </Td> <Td> 0.00059 </Td> <Td> 1.711 ± 0.005 </Td> <Td> 0.378 </Td> <Td> 0.0385 </Td> <Td> moon of Uranus </Td> <Td> round </Td> <Td> 19 </Td> </Tr> <Tr> <Td> 2007 OR 225088 </Td> <Td> </Td> <Td> 7002767000000000000 ♠ 767 + 38 − 113 </Td> <Td> 0.1200 </Td> <Td> 1.88 </Td> <Td> 0.0017 </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> resonant KBO (3: 10) </Td> <Td> unknown </Td> <Td> 20 </Td> </Tr> <Tr> <Td> Rhea Saturn V </Td> <Td> </Td> <Td> 7002763800000000000 ♠ 763.8 ± 1.0 </Td> <Td> 0.1199 </Td> <Td> 1.87 </Td> <Td> 0.0017 </Td> <Td> 2.3166 </Td> <Td> 0.00039 </Td> <Td> 1.236 ± 0.005 </Td> <Td> 0.26 </Td> <Td> 0.027 </Td> <Td> moon of Saturn </Td> <Td> round (HE, disputed) </Td> <Td> 21 </Td> </Tr> <Tr> <Td> Oberon Uranus IV </Td> <Td> </Td> <Td> 7002761400000000000 ♠ 761.4 ± 2.6 </Td> <Td> 0.1195 </Td> <Td> 1.85 </Td> <Td> 0.0017 </Td> <Td> 3.014 </Td> <Td> 0.0005 </Td> <Td> 1.63 ± 0.05 </Td> <Td> 0.347 </Td> <Td> 0.035 </Td> <Td> moon of Uranus </Td> <Td> round </Td> <Td> 22 </Td> </Tr> <Tr> <Td> Iapetus Saturn VIII </Td> <Td> </Td> <Td> 7002734500000000000 ♠ 734.5 ± 2.8 </Td> <Td> 0.1153 </Td> <Td> 1.55 </Td> <Td> 0.0014 </Td> <Td> 1.9739 </Td> <Td> 0.00033 </Td> <Td> 1.088 ± 0.013 </Td> <Td> 0.223 </Td> <Td> 0.0227 </Td> <Td> moon of Saturn </Td> <Td> round (not in HE) </Td> <Td> 23 </Td> </Tr> <Tr> <Td> Makemake 136472 </Td> <Td> </Td> <Td> 7002715000000000000 ♠ 715 + 19 − 11 </Td> <Td> 0.112 </Td> <Td> 1.7 </Td> <Td>. 0016 </Td> <Td> </Td> <Td> </Td> <Td> 2.3 ± 0.9 </Td> <Td> </Td> <Td> </Td> <Td> dwarf planet; cubewano </Td> <Td> round </Td> <Td> 24 </Td> </Tr> <Tr> <Td> Haumea 136108 </Td> <Td> </Td> <Td> 7002620000000000000 ♠ 620 + 34 − 29 </Td> <Td> 0.097 </Td> <Td> 1.3--1.6 </Td> <Td> 0.001 </Td> <Td> 4.006 </Td> <Td> 0.00067 </Td> <Td> 2.55 </Td> <Td> 0.44 </Td> <Td> 0.045 </Td> <Td> dwarf planet; resonant KBO (7: 12); trinary </Td> <Td> round (scalene ellipsoid) </Td> <Td> 25 </Td> </Tr> <Tr> <Td> Charon Pluto I </Td> <Td> </Td> <Td> 7002606000000000000 ♠ 606 ± 3 </Td> <Td> 0.0951 </Td> <Td> 0.87 </Td> <Td> 0.0008 </Td> <Td> 1.52 </Td> <Td> 0.00025 </Td> <Td> 1.702 ± 0.021 </Td> <Td> 0.279 </Td> <Td> 0.028 </Td> <Td> moon of Pluto </Td> <Td> round </Td> <Td> 26 </Td> </Tr> <Tr> <Td> Umbriel Uranus II </Td> <Td> </Td> <Td> 7002584700000000000 ♠ 584.7 ± 2.8 </Td> <Td> 0.0918 </Td> <Td> 0.84 </Td> <Td> 0.0008 </Td> <Td> 1.2 </Td> <Td> 0.00020 </Td> <Td> 1.39 ± 0.16 </Td> <Td> 0.234 </Td> <Td> 0.024 </Td> <Td> moon of Uranus </Td> <Td> round </Td> <Td> 27 </Td> </Tr> <Tr> <Td> Ariel Uranus I </Td> <Td> </Td> <Td> 7002578900000000000 ♠ 578.9 ± 0.6 </Td> <Td> 0.0909 </Td> <Td> 0.81 </Td> <Td> 0.0007 </Td> <Td> 1.35 </Td> <Td> 0.000226 </Td> <Td> 1.66 ± 0.15 </Td> <Td> 0.269 </Td> <Td> 0.027 </Td> <Td> moon of Uranus </Td> <Td> round </Td> <Td> 28 </Td> </Tr> <Tr> <Td> Dione Saturn IV </Td> <Td> </Td> <Td> 7002561400000000000 ♠ 561.4 ± 0.4 </Td> <Td> 0.0881 </Td> <Td> 0.73 </Td> <Td> 0.0007 </Td> <Td> 1.096 </Td> <Td> 0.000183 </Td> <Td> 1.478 ± 0.003 </Td> <Td> 0.232 </Td> <Td> 0.0237 </Td> <Td> moon of Saturn </Td> <Td> round (not in HE) </Td> <Td> 29 </Td> </Tr> <Tr> <Td> Quaoar 50000 </Td> <Td> </Td> <Td> 7002555000000000000 ♠ 555 ± 3 </Td> <Td> 0.0871 </Td> <Td> </Td> <Td> </Td> <Td> 1.4 ± 0.1 </Td> <Td> 0.0002 </Td> <Td> 2.2 ± 0.4 </Td> <Td> 0.125 </Td> <Td> 0.0127 </Td> <Td> cubewano; binary </Td> <Td> unknown </Td> <Td> 30 </Td> </Tr> <Tr> <Td> Tethys Saturn III </Td> <Td> </Td> <Td> 7002531100000000000 ♠ 531.1 ± 0.6 </Td> <Td> 0.0834 </Td> <Td> 0.624 </Td> <Td> 0.0006 </Td> <Td> 0.6173 </Td> <Td> 0.000103 </Td> <Td> 0.984 ± 0.003 </Td> <Td> 0.145 </Td> <Td> 0.015 </Td> <Td> moon of Saturn </Td> <Td> round (not in HE) </Td> <Td> 31 </Td> </Tr> <Tr> <Td> Sedna 90377 </Td> <Td> </Td> <Td> 7002500000000000000 ♠ 500 ± 80 </Td> <Td> 0.0785 </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> sednoid; detached object </Td> <Td> unknown </Td> <Td> 32 </Td> </Tr> <Tr> <Td> Ceres </Td> <Td> </Td> <Td> 7002473000000000000 ♠ 473 </Td> <Td> 0.0742 </Td> <Td> 0.433 </Td> <Td> 0.0004 </Td> <Td> 0.939 </Td> <Td> 0.000157 </Td> <Td> 2.17 </Td> <Td> 0.29 </Td> <Td> 0.030 </Td> <Td> dwarf planet; belt asteroid </Td> <Td> round (HE) </Td> <Td> 33 </Td> </Tr> <Tr> <Td> 2002 MS 307261 </Td> <Td> </Td> <Td> 7002467000000000000 ♠ 467 ± 24 </Td> <Td> 0.0733 </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> cubewano </Td> <Td> unknown </Td> <Td> 34 </Td> </Tr> <Tr> <Td> Orcus 90482 </Td> <Td> </Td> <Td> 7002458000000000000 ♠ 458 ± 13 </Td> <Td> 0.0719 </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> 2.47 </Td> <Td> </Td> <Td> </Td> <Td> plutino; binary </Td> <Td> unknown </Td> <Td> 35 </Td> </Tr> <Tr> <Td> Salacia 120347 </Td> <Td> </Td> <Td> 7002425000000000000 ♠ 425 ± 23 </Td> <Td> 0.0667 </Td> <Td> </Td> <Td> </Td> <Td> 0.45 ±? </Td> <Td> </Td> <Td> 1.16 + 0.59 − 0.36 </Td> <Td> </Td> <Td> </Td> <Td> cubewano; binary </Td> <Td> unknown </Td> <Td> 36 </Td> </Tr> <Tr> <Th_colspan="14"> Notes: <Dl> <Dd> Name of body, including alternative names using Roman numerals to designate moons (such as "Jupiter I" for Io), and numbers to designate minor planets </Dd> <Dd> Mean radius including uncertainties </Dd> <Dd> Given as surface gravity (1 bar for gaseous planets) </Dd> <Dd> Ranking by radius of the largest bodies in the Solar System, may not reflect the latest updates of measured radii </Dd> <Dd> star giant planet terrestrial planet the Moon, moon of Earth moon of Jupiter moon of Saturn moon of Uranus moon of Neptune moon of Pluto </Dd> </Dl> </Th> </Tr> </Table> <Tr> <Th> Body </Th> <Th> Image </Th> <Th_colspan="2"> Radius </Th> <Th_colspan="2"> Volume </Th> <Th_colspan="2"> Mass </Th> <Th> Density </Th> <Th_colspan="2"> Gravity </Th> <Th> Type </Th> <Th> Shape </Th> <Th> #</Th> </Tr>

Largest moon in the solar system compared to earth