- Earth's Moon: It is Earth's only natural satellite, and the fifth largest moon in the Solar System. The average centre-to-centre distance from the Earth to the Moon is 384,403 km which is about thirty times the diameter of the Earth. The Moon has a diameter of 3,474 km. The volume of the Moon is close to 1/50th that of Earth. The gravitational pull at its surface is about 1/6th of Earth's. The Moon makes a complete orbit around the Earth every 27.3 days, and the periodic variations in the geometry of the Earth-Moon-Sun system are responsible for the lunar phases that repeat every 29.5 days.
- Jupiter's moons
Sixty-three moons orbiting Jupiter have been discovered.
Inner moons Metis · Adrastea · Amalthea · Thebe
Galilean moons Io · Europa · Ganymede · Callisto
Themisto
Himalia group Leda · Himalia · Lysithea · Elara ·
S/2000 J 11
Carpo · S/2003 J 12
Ananke group core Ananke · Praxidike · Harpalyke ·
Iocaste · Euanthe · Thyone
peripheral Euporie · S/2003 J 3 · S/2003 J 18 · Thelxinoe
· Helike · Orthosie · S/2003 J 16 · Hermippe
· Mneme · S/2003 J 15
Carme group S/2003 J 17 · S/2003 J 10 · Pasithee ·
Chaldene · Arche · Isonoe · Erinome · Kale ·
Aitne · Taygete · S/2003 J 9 · Carme · S/2003
J 5 · S/2003 J 19 · Kalyke · Eukelade · Kallichore
Pasiphaë group Eurydome · S/2003 J 23 · Hegemone ·
Pasiphaë · Sponde · Cyllene · Megaclite ·
S/2003 J 4 · Callirrhoe · Sinope · Autonoe ·
Aoede · Kore
S/2003 J 2
-Mars' Moons
Mars has two tiny natural moons, Phobos and Deimos, which are thought to
be captured asteroids.
Name Diameter (km) Mass (kg) Semi-major
axis (km) Orbital
period (h) Average moonrise
period (h)
Phobos 22.2 km 1.08×1016 9377 km 7.66 11.12 h
Deimos 12.6 km 2×1015 23,460 km 30.35 131
- Mercury's Moon
Mercury has no known moon.
- Neptune's Moons
Neptune has thirteen known moons. The largest by far is Triton; it is the
only one massive enough to have achieved hydrostatic equilibrium.
Name Diameter (km) Mass
(1016 kg) Semi-major axis (km) Orbital period‡ (d) Inclination (°)
to Neptune's Equator
Naiad
67 ~19 48,227 0.294 4.7°
Thalassa
83 ~35 50,075 0.311 0.2°
Despina
152 ~210 52,526 0.335 0.1°
Galatea
175 212 61,953 0.429 0.1°
Larissa
195 ~420 73,548 0.555 0.2°
Proteus
418 ~4,400 117,647 1.122 0.6°
Triton
2707 2,140,000 354,800 ?5.877 156.8°
Nereid
340 ~2,200 5,513,400 360.14 27.6°
Halimede
60 ~9 15,728,000 ?1879.71
Sao
38 ~9 22,422,000 2914.07
Laomedeia
38 ~9 23,571,000 3167.85
Psamathe
28 ~1.5 46,695,000 ?9115.91
Neso
60 ~9 48,387,000
(0.32 AU)
?9373.99
- Pluto's Moons
Pluto has three known moons. The largest, Charon, is proportionally larger,
compared to its primary, than any other satellite of a known planet or dwarf
planet in the solar system. Nix and Hydra, are much smaller.
Name Mean diameter (km) Mass (×1021 kg) Semi-major
axis (km) Orbital period (days) Eccentricity Inclination
(to Pluto's equator)
Pluto 2306 ± 20 13.05 ± 0.07 2390 6.387230 0 -
Charon 1207 ± 3 1.52 ± 0.06 19 571 ± 4 6.387230 0 (0.000%
± 0.007%) 0.00° ± 0.014°
Nix 46-137 < 0.002 48 675 ± 120 24.856 ± 0.001 ~0 (0.2%
± 0.2%) 0.04° ± 0.22°
Hydra 61-167 < 0.002 64 780 ± 90 38.206 ± 0.001 0.5% ±
0.1% 0.22° ± 0.12°
- Saturn's Moons
Saturn has 60 named natural satellites, many of which may be as small as
two-to-three kilometres across, plus hundreds of observed "moonlets"
only a few tens or hundreds of meters across in the A Ring. Seven of these
moons are large enough to have achieved hydrostatic equilibrium and so would
be considered dwarf planets if they were in orbit about the Sun; indeed
one of them, Titan, is massive enough to retain an atmosphere denser than
our own.
Name Diameter (km) Semi-major
axis (km) Orbital
period (d) Inclination (°)
(to Saturn's
equator)
moonlets 0.06 to 0.14 130,000
Pan 30 (35 × 35 × 23) 133,584 +0.57505 0.001°
Daphnis 6 ? 8 136,505 +0.59408 [ ? 0°
Atlas 31 (46 × 38 × 19) 137,670 +0.60169 [ 0.003°
Prometheus 86 (119 × 87 × 61) 139,380 +0.61299 [ 0.008°
Pandora 81 (103 × 80 × 64) 141,720 +0.62850 [ 0.050°
Epimetheus 113 (135 × 108 × 105) 151,422 +0.69433 0.335°
Janus 179 (193 × 173 × 137) 151,472 +0.69466 0.165°
Mimas 397 (415 × 394 × 381) 185,404 +0.942422 1.566°
Methone 3 194,440 +1.00957 0.007°
Anthe ~2 197,700 1.03650 0.1°
Pallene 4 212,280 +1.15375 0.181°
Enceladus 504 (513 × 503 × 497) 237,950 +1.370218 0.010°
Tethys 1066 (1081 × 1062 × 1055) 294,619 +1.887802 0.168°
Telesto 24 (29 × 22 × 20) 1.158°
Calypso 21 (30 × 23 × 14) 1.473°
Dione 1123 (1128 × 1122 × 1121) 377,396 +2.736915 0.002°
Helene 33 (36 × 32 × 30) 0.212°
Polydeuces 3.5 0.177°
Rhea 1529 (1535 × 1525 × 1526) 527,108 +4.518212 0.327°
Titan 5151 1,221,930 +15.94542 1.634°
Hyperion 292 (360 × 280 × 225) 1,481,010 +21.27661 0.568°
Iapetus 1472 (1494 × 1498 × 1425) 3,560,820 +79.3215 7.570°
Kiviuq ~16 11 294 800 +448.16 49.087°
Ijiraq ~12 11 355 316 +451.77 50.212°
Phoebe 220 (230 × 220 × 210) 12 869 700 ?545.09 173.047°
Paaliaq ~22 15 103 400 +692.98 46.151°
Skathi ~8 15 672 500 ?732.52 149.084°
Albiorix ~32 16 266 700 +774.58 38.042°
S/2007 S 2 ~6 16 560 000 ?792.96 176.68°
Bebhionn ~6 17 153 520 +838.77 40.484°
Erriapus ~10 17 236 900 +844.89 38.109°
Skoll ~6 17 473 800 ?862.37 155.624°
Siarnaq ~40 17 776 600 +884.88 45.798°
Tarqeq ~7 17 910 600 +894.86 49.904°
S/2004 S 13 ~6 18 056 300 ?905.85 167.379°
Greip ~6 18 065 700 ?906.56 172.666°
Hyrrokkin ~8 18 168 300 ?914.29 153.272°
Jarnsaxa ~6 18 556 900 ?943.78 162.861°
Tarvos ~15 18 562 800 +944.23 34.679°
Mundilfari ~7 18 725 800 ?956.70 169.378°
S/2006 S 1 ~6 18 930 200 ?972.41 154.232°
S/2004 S 17 ~4 19 099 200 ?985.45 166.881°
Bergelmir ~6 19 104 000 ?985.83 157.384°
Narvi ~7 19 395 200 ?1008.45 137.292°
Suttungr ~7 19 579 000 ?1022.82 174.321°
Hati ~6 19 709 300 ?1033.05 163.131°
S/2004 S 12 ~5 19 905 900 ?1048.54 164.042°
Farbauti ~5 19 984 800 ?1054.78 158.361°
Thrymr ~7 20 278 100 ?1078.09 174.524°
Aegir ~6 20 482 900 ?1094.46 167.425°
S/2007 S 3 ~5 20 518 500 ~ ?1100 177.22°
Bestla ~7 20 570 000 ?1101.45 147.395°
S/2004 S 7 ~6 20 576 700 ?1101.99 165.596°
S/2006 S 3 ~6 21 076 300 ?1142.37 150.817°
Fenrir ~4 21 930 644 ?1212.53 162.832°
Surtur ~6 22 288 916 ?1242.36 166.918°
Kari ~7 22 321 200 ?1245.06 148.384°
Ymir ~18 22 429 673 ?1254.15 172.143°
Loge ~6 22 984 322 ?1300.95 166.539°
Fornjot ~6 24 504 879 ?1432.16 167.886°
- Uranus' Moons
Uranus has twenty-seven named moons. Five of them are massive enough to
have achieved hydrostatic equilibrium and so would be considered dwarf planets
if they were in orbit about the Sun.
Name
Mean diameter (km) Mass (kg) Semi-major
axis (km) Orbital period (day) Inclination (°)
(to Uranus' equator)
Cordelia 42 ± 6 5.0×1016? 49,751 0.335034 0.08479°
Ophelia 46 ± 8 5.1×1016? 53,764 0.376400 0.1036°
Bianca 54 ± 4 9.2×1016? 59,165 0.434579 0.193°
Cressida 82 ± 4 3.4×1017? 61,766 0.463570 0.006°
Desdemona 68 ± 8 2.3×1017? 62,658 0.473650 0.11125°
Juliet 106 ± 8 8.2×1017? 64,360 0.493065 0.065°
Portia 140 ± 8 1.7×1018? 66,097 0.513196 0.059°
Rosalind 72 ± 12 2.5×1017? 69,927 0.558460 0.279°
Cupid ~ 18 3.8×1015? 74,800 0.618 0.1°
Belinda 90 ± 16 4.9×1017? 75,255 0.623527 0.031°
Perdita 30 ± 6 1.8×1016? 76,420 0.638 0.0°
Puck 162 ± 4 2.9×1018? 86,004 0.761833 0.3192°
Mab ~ 25 1.0×1016? 97,734 0.923 0.1335°
Miranda 471.6 ± 1.4 (6.6 ± 0.7)×1019 129,390 1.413479
4.232°
Ariel 1157.8 ± 1.2 (1.35 ± 0.12)×1021 191,020 2.520379
0.260°
Umbriel 1169.4 ± 5.6 (1.17 ± 0.13)×1021 266,300 4.144177
0.205°
Titania 1577.8 ± 3.6 (3.53 ± 0.09)×1021 435,910 8.705872
0.340°
Oberon 1522.8 ± 5.2 (3.01 ± 0.07)×1021 583,520 13.463239
0.058°
Francisco ~ 22 7.2×1015? 4,276,000 -266.56* 147.459°
Caliban ~ 72 2.5×1017? 7,231,000 -579.73* 139.885°
Stephano ~ 32 2.2×1016? 8,004,000 -677.37* 141.873°
Trinculo ~ 18 3.9×1015? 8,504,000 -749.24* 166.252°
Sycorax ~ 150 2.3×1018? 12,179,000 -1288.28* 152.456°
Margaret ~ 20 5.4×1015? 14,345,000 +1687.01 51.455°
Prospero ~ 50 8.5×1016? 16,256,000 -1978.29* 146.017°
Setebos ~ 48 7.5×1016? 17,418,000 -2225.21* 145.883°
Ferdinand ~ 20 5.4×1015? 20,901,000 -2887.21* 167.346°
- Venus' Moon
Until now no moon has been discovered around Venus.
- Natural satellite, or Moon: It is an object that orbits a planet or other
body larger than itself and which is not man-made. Such objects are often
called moons. The term is normally used to identify non-artificial satellites
of planets, dwarf planets, or minor planets. There are 240 known moons within
the Solar System, including 165 orbiting the planets, 4 orbiting dwarf planets,
and dozens more orbiting small solar system bodies. Other stars and their
planets are very likely to have natural satellites, although none have yet
been observed.