Use these up-to-date tables to learn about the moons of the solar system, including the plethora of Jupiter's moons and the weird menagerie of Saturn's moons.

Pandora
Cassini snapped this image of Saturn's moon Pandora on December 21, 2016, from a range of 25,200 miles (40,500 kilometers).
NASA / JPL / Space Science Institute

Discovering a new moon in the solar system used to be a rare event. After Gerard Kuiper found Uranus's moon Miranda in 1948 and Seth Nicholson found Jupiter's Ananke in 1951, the total count of natural planetary satellites stood at 31: Jupiter led with 12, followed by Saturn (9), Uranus (5), Neptune (2), Mars (2), and Earth (1). (Notably, Mercury and Venus are the only planets in the solar system that do not have moons.)

In the ensuing three decades, finding solar system moons largely fell to NASA spacecraft. After Voyager 2's flyby of Neptune in 1989, the total number of solar system moons had nearly doubled to 60. However, the advent of sensitive electronic cameras has put ground-based observers back in the driver's seat, resulting in several dozens of finds over the past few years. Indeed, some of the new objects are so small, only a few kilometers across, that they stretch the traditional notion of what constitutes a "moon." Sometimes faint objects appear fleetingly in images and are never seen again; others require patient follow-up observations over months or years to confirm that they orbit a planet.

While comets bear the surname(s) of their discoverer(s), and observers retain naming rights for asteroids, those who spot planetary moons must yield naming privilege to the International Astronomical Union. By convention, the IAU does not name a satellite until its orbit is known precisely — a threshold sometimes not reached until decades after the initial discovery.

The following is a tabulation of known planetary satellites, last updated in February 2019. As of then, the count stood at 185, distributed as follows: Earth 1, Mars 2, Jupiter 79, Saturn 62, Uranus 27, Neptune 14. Among the IAU-approved dwarf planets, Pluto has 5, Eris 1, Makemake 1, and Haumea 2. However, the locations of seven Jovian and seven Saturnian moonlets are known so poorly that they are effectively lost.

In the table below and on the following pages, the diameter of each satellite and the orbital distance from its planet's center (semimajor axis) are in kilometers; eccentricity (Ecc.) is the elongation of the satellite's orbit; and inclination is the tilt of its orbit plane, in degrees, with respect to the planet's equatorial plane (for inner moons) or the ecliptic plane (for outer moons). Names of "lost" objects are shown in italics.

List of Confirmed Moons in the Solar System

Satellite
Diameter
(km)
Visual
magnitude
Distance
(km)
Orbital
period (days)
Eccen-
tricity
Inclina-
tion (°)
EARTH
Moon 3,474 –12.7 384,400 27.3 0.055 5.1
MARS
Phobos 22 11.4 9,380 0.3 0.015 1.1
Deimos 12 12.5 23,460 1.3 0.000 1.8

List of Confirmed Moons in the Solar System

Satellite
Diameter
(km)
Visual
magnitude
Distance
(km)
Orbital
period (days)
Eccen-
tricity
Inclina-
tion (°)
JUPITER
Metis 44 17.5 128,000 0.3 0.001 0.0
Adrastea 16 18.7 129,000 0.3 0.002 0.1
Amalthea 168 14.1 181,400 0.5 0.003 0.4
Thebe 98 16.0 221,900 0.7 0.018 1.1
Io 3,643 5.0 421,800 1.8 0.004 0.0
Europa 3,122 5.3 671,100 3.6 0.009 0.5
Ganymede 5,262 4.6 1,070,400 7.2 0.001 0.2
Callisto 4,821 5.7 1,882,700 16.7 0.007 0.2
Themisto 9 21.0 7,507,000 130.0 0.242 43.1
Leda 18 20.2 11,165,000 240.9 0.164 27.5
Himalia 160 14.8 11,461,000 250.6 0.162 27.5
Ersa 3 22.9 11,483,000 252.0 0.094 30.6
Pandia 3 23.0 11,525,000 252.1 0.180 28.2
Lysithea 38 18.2 11,717,000 259.2 0.112 27.7
Elara 78 16.6 11,741,000 259.6 0.217 26.6
Dia 4 22.4 12,118,000 287.0 0.211 28.2
Carpo 3 23.0 16,989,000 456.1 0.430 51.4
Valetudo 1 24.0 18,980,000 533.3 0.222 34.0
S/2003 J12 1 23.9 19,002,500 433.3 0.376 145.8
Euporie 2 23.1 19,302,000 550.7 0.144 145.6
Eupheme 2 23.4 20,221,000 583.9 0.197 147.6
S/2003 J18 2 23.4 20,274,000 588.0 0.105 146.4
S/2010 J2 1 23.9 20,307,150 588.1 0.307 150.4
S/2017 J7 2 23.6 20,627,000 602.6 0.215 143.4
S/2016 J1 1 24.0 20,650,850 602.7 0.141 139.8
S/2017 J3 2 23.4 20,694,000 606.3 0.148 147.9
Orthosie 2 23.1 20,721,000 622.6 0.281 145.9
Ananke 28 18.9 20,741,000 610.0 0.244 148.9
Euanthe 3 22.8 20,799,000 620.6 0.232 148.9
Thyone 4 22.3 20,940,000 627.3 0.229 148.5
S/2003 J16 2 23.3 21,000,000 595.4 0.230 148.5
Mneme 2 23.3 21,069,000 620.0 0.227 148.6
Harpalyke 4 22.2 21,105,000 623.3 0.226 148.6
Hermippe 4 22.1 21,131,000 633.9 0.210 150.7
Praxidike 7 21.2 21,147,000 625.3 0.230 149.0
Thelxinoe 2 23.5 21,162,000 628.1 0.221 151.4
Helike 4 22.6 21,263,000 634.8 0.156 154.8
Iocaste 5 21.8 21,269,000 631.5 0.216 149.4
S/2017 J9 3 22.8 21,487,000 639.2 0.229 152.7
Kale 2 23.0 22,407,000 686.7 0.260 165.0
S/2003 J9 1 23.7 22,441,700 683.0 0.269 164.5
S/2017 J6 2 23.5 22,455,000 683.0 0.557 155.2
S/2011 J1 2 23.7 22,462,000 686.6 0.233 163.3
S/2003 J19 2 23.7 22,757,000 697.6 0.257 166.7
Philophrosyne 2 23.5 22,820,000 701.3 0.194 143.6
Eurydome 3 22.7 22,865,000 717.3 0.276 150.3
Arche 3 22.8 22,931,000 723.9 0.259 165.0
Autonoe 4 22.0 23,039,000 762.7 0.334 152.9
Pasithee 2 23.2 23,096,000 719.5 0.267 165.1
Herse 2 23.4 23,097,000 715.4 0.200 164.2
Chaldene 4 22.5 23,179,000 723.8 0.251 165.2
Isonoe 4 22.5 23,217,000 725.5 0.246 165.2
Aitne 3 22.7 23,231,000 730.2 0.264 165.1
S/2017 J5 2 23.5 23,232,000 719.5 0.284 164.3
S/2017 J8 1 24 23,232,700 719.6 0.312 164.7
S/2003 J4 2 23.0 23,257,900 723.2 0.204 144.9
Erinome 3 22.8 23,279,000 728.3 0.266 164.9
S/2017 J2 2 23.5 23,303,000 723.1 0.236 166.4
S/2010 J1 2 23.3 23,314,300 723.2 0.320 163.2
Taygete 5 21.9 23,360,000 732.2 0.252 165.2
S/2011 J2 1 23.6 23,463,900 730.5 0.332 153.6
Sponde 2 23.0 23,487,000 748.3 0.312 151.0
S/2017 J1 2 23.8 23,547,100 734.2 0.397 149.2
Kalyke 5 21.8 23,583,000 743.0 0.245 165.2
Pasiphae 58 16.9 23,624,000 708.0 0.409 151.4
Eukelade 4 22.6 23,661,000 746.4 0.272 165.5
Eirene 4 22.5 23,731,800 759.7 0.220 163.1
Megaclite 6 21.7 23,806,000 752.8 0.421 152.8
Carme 46 17.9 23,926,000 756.1 0.253 164.9
Sinope 38 18.3 23,939,000 724.5 0.250 158.1
Hegemone 3 22.8 23,947,000 739.6 0.328 155.2
Aoede 4 22.5 23,981,000 761.5 0.432 158.3
Kallichore 2 23.7 24,043,000 764.7 0.264 165.5
S/2003 J23 2 23.6 24,055,500 759.7 0.309 149.2
Callirrhoe 7 20.8 24,102,000 758.8 0.283 147.1
S/2003 J10 2 23.6 24,249,600 767.0 0.214 164.1
Cyllene 2 23.2 24,349,000 737.8 0.319 149.3
Kore 2 23.6 24,543,000 779.2 0.325 145.0
S/2003 J2 2 23.2 28,570,000 982.5 0.380 151.8

List of Confirmed Moons in the Solar System

Satellite
Diameter
(km)
Visual
magnitude
Distance
(km)
Orbital
period (days)
Eccen-
tricity
Inclina-
tion (°)
SATURN
S/2009 S1 0.3 28.0 117,000 0.6 0.000 0.0
Pan 28 19.4 133,580 0.6 0.000 0.0
Daphnis 7 24.0 136,500 0.6 0.003 0.0
Atlas 32 18.5 137,770 0.6 0.001 0.0
Prometheus 86 15.8 139,430 0.6 0.002 0.0
Pandora 81 16.4 141,810 0.6 0.004 0.1
Janus 178 14.4 151,450 0.7 0.010 0.2
Epimetheus 113 15.6 151,450 0.7 0.016 0.4
Aegaeon 0.5 25 167,420 0.8 0.000 0.0
Mimas 397 12.8 185,540 0.9 0.020 1.6
Methone 3 23 194,400 1.0 0.000 0.0
Anthe 2 24.0 196,900 1.0 0.001 0.2
Pallene 4 23 212,280 1.2 0.004 0.0
Enceladus 499 11.8 238,040 1.4 0.000 0.0
Tethys 1,060 10.2 294,670 1.9 0.000 1.1
Telesto 25 18.5 294,720 1.9 0.000 1.2
Calypso 21 18.7 294,720 1.9 0.001 1.5
Polydeuces 4 23.0 377,200 2.7 0.019 0.2
Dione 1,118 10.4 377,420 2.7 0.002 0.0
Helene 31 18.4 377,440 2.7 0.000 0.2
Rhea 1,528 9.6 527,070 4.5 0.000 0.3
Titan 5,150 8.4 1,221,860 16.0 0.029 0.3
Hyperion 283 14.4 1,500,930 21.3 0.023 0.6
Iapetus 1,436 11.0 3,560,850 79.3 0.029 8.3
Kiviuq 14 22.0 11,384,000 449.2 0.332 46.7
Ijiraq 10 22.6 11,408,000 451.4 0.272 47.5
Phoebe 220 16.4 12,947,920 548.0 0.163 175.2
Paaliaq 19 21.3 15,204,000 687.0 0.332 46.2
Skathi 6 23.6 15,635,000 728.1 0.272 152.6
S/2004 S37 4 25.1 16,003,300 752.9 0.506 164.0
S/2007 S2 6 24.4 16,055,000 759.7 0.237 176.7
Albiorix 26 20.5 16,393,000 783.5 0.480 34.1
Bebhionn 6 24.1 17,116,000 834.9 0.468 35.1
S/2004 S31 4 24.9 17,402,800 853.8 0.242 48.1
S/2004 S29 4 24.9 17,470,700 858.8 0.472 44.4
Erriapus 9 23.0 17,602,000 871.1 0.472 34.5
Skoll 6 24.5 17,668,000 878.2 0.464 161.0
Tarqeq 7 23.9 17,962,000 885.2 0.168 46.3
Siarnaq 32 20.1 18,182,000 895.5 0.280 45.8
Tarvos 13 22.1 18,243,000 926.4 0.538 33.7
S/2004 S13 6 24.5 18,406,000 933.5 0.259 168.8
Hyrrokkin 8 23.5 18,440,000 931.9 0.336 151.5
Greip 6 24.4 18,457,000 937.1 0.315 174.8
Mundilfari 6 23.8 18,653,000 952.8 0.210 167.4
S/2006 S1 6 24.6 18,780,000 962.2 0.141 156.2
S/2007 S3 5 24.9 18,938,000 977.8 0.185 177.6
S/2004 S20 4 25.0 19,211,000 990.2 0.204 163.1
Bergelmir 6 24.2 19,336,300 1,005.8 0.142 158.6
Narvi 8 24.0 19,349,000 1,003.9 0.430 145.7
Jarnsaxa 6 24.7 19,354,000 1,006.9 0.218 163.6
S/2004 S17 4 25.2 19,448,000 1,014.6 0.180 168.2
Suttungr 6 23.9 19,468,000 1,016.7 0.114 175.8
S/2004 S27 4 24.5 19,776,700 1,033.0 0.120 167.1
Hati 6 24.4 19,868,000 1,040.2 0.371 165.8
S/2004 S12 5 24.8 19,886,000 1,046.1 0.327 165.3
Bestla 7 23.8 20,209,000 1,088.0 0.514 145.1
S/2004 S22 3 25.3 20,379,900 1,080.4 0.257 177.4
Farbauti 5 24.7 20,390,000 1,086.7 0.241 156.5
Thrymr 6 23.9 20,418,000 1,092.0 0.466 177.7
S/2004 S30 3 25.4 20,424,000 1,084.1 0.113 156.3
S/2004 S25 3 25.2 20,544,500 1,095.0 0.457 173.3
Aegir 6 24.4 20,751,000 1,117.8 0.252 166.7
S/2004 S7 6 24.5 21,000,000 1,140.2 0.529 165.7
S/2006 S3 6 24.6 21,308,400 1,161.5 0.379 158.6
S/2004 S23 4 24.8 21,427,000 1,164.3 0.399 177.7
S/2004 S32 4 25.0 21,564,200 1,175.3 0.262 158.5
S/2004 S28 4 24.9 21,791,300 1,197.2 0.133 171.0
S/2004 S35 4 24.6 21,953,200 1,208.1 0.182 176.4
Kari 7 23.9 22,093,000 1,231.2 0.470 152.8
Fenrir 4 25.0 22,454,000 1,260.4 0.135 165.0
S/2004 S39 2 25.5 22,790,400 1,277.5 0.081 167.6
Surtur 6 24.8 22,941,000 1,297.1 0.446 170.0
S/2004 S38 4 25.1 23,006,200 1,295.8 0.381 155.0
Loge 6 24.6 23,059,000 1,311.4 0.187 167.7
Ymir 16 21.7 23,128,000 1,315.1 0.334 173.5
S/2004 S24 3 25.2 23,231,300 1,317.6 0.049 36.8
S/2004 S36 3 25.3 23,698,700 1,354.2 0.667 147.6
S/2004 S33 4 25.0 23,764,800 1,361.5 0.417 161.5
S/2004 S21 3 25.4 23,810,400 1,365.1 0.312 154.6
S/2004 S34 3 25.3 24,358,900 1,412.5 0.267 165.7
Fornjot 6 24.6 25,146,000 1,494.1 0.208 170.4
S/2004 S26 4 25.0 26,737,800 1,624.2 0.148 171.3

List of Confirmed Moons in the Solar System

Satellite
Diameter
(km)
Visual
magnitude
Distance
(km)
Orbital
period (days)
Eccen-
tricity
Inclina-
tion (°)
URANUS
Cordelia 40 23.6 49,800 0.3 0.000 0.1
Ophelia 23 23.3 53,800 0.4 0.010 0.1
Bianca 51 22.5 59,200 0.4 0.001 0.2
Cressida 80 21.6 61,800 0.5 0.000 0.0
Desdemona 64 22.0 62,700 0.5 0.000 0.1
Juliet 94 21.1 64,400 0.5 0.001 0.1
Portia 135 20.4 66,100 0.5 0.000 0.1
Rosalind 72 21.8 69,900 0.6 0.000 0.3
Cupid 10 26 74,390 0.6 0.001 0.1
Belinda 81 21.5 75,300 0.6 0.000 0.0
Perdita 40 23.6 76,420 0.6 0.000 0.5
Puck 162 19.8 86,000 0.8 0.000 0.3
Mab 10 26 97,740 0.9 0 0.1
Miranda 472 15.8 129,900 1.4 0.001 4.3
Ariel 1,158 13.7 190,900 2.5 0.001 0.0
Umbriel 1,169 14.5 266,000 4.1 0.004 0.1
Titania 1,578 13.5 436,300 8.7 0.001 0.1
Oberon 1,523 13.7 583,500 13.5 0.001 0.1
Francisco 12 25 4,282,900 267.1 0.132 147.2
Caliban 89 22.4 7,231,100 579.7 0.181 140.9
Stephano 20 24.1 8,007,400 677.5 0.225 143.8
Trinculo 10 25.4 8,505,200 749.4 0.219 167.0
Sycorax 190 20.8 12,179,400 1,288.4 0.522 159.4
Margaret 11 25.2 14,146,700 1,661.0 0.677 57.4
Prospero 30 20.8 16,267,800 1,978.4 0.444 151.2
Setebos 30 23.3 17,420,400 2,225.1 0.591 158.2
Ferdinand 12 25.1 20,430,000 2,790.0 0.399 169.8
NEPTUNE
Naiad 58 24.6 48,230 0.3 0.000 4.7
Thalassa 80 23.9 50,070 0.3 0.000 0.1
Despina 148 22.5 52,530 0.3 0.000 0.1
Galatea 158 22.4 61,950 0.4 0.001 0.0
Larissa 192 22.0 73,550 0.6 0.001 0.2
Hippocamp 34 26.5 105,300 0.9 0.000 0.0
Proteus 416 20.3 117,650 1.1 0.001 0.1
Triton 2,707 13.5 354,760 5.9 0.000 156.9
Nereid 340 19.7 5,513,820 360.1 0.751 7.1
Halimede 54 24.2 16,611,000 1,879.1 0.265 112.7
Sao 31 25.4 22,228,000 2,912.7 0.137 53.5
Laomedeia 37 25 23,567,000 3,171.3 0.400 37.9
Psamathe 36 25.1 48,096,000 9,074.3 0.380 126.3
Neso 43 24.7 49,285,000 9,740.7 0.571 136.4
PLUTO
Charon 1,186 17.3 17,536 6.4 0.002 96.1
Styx 10 27 42,000 20.2 0.000 96.2
Nix 100 23.4 48,708 24.9 0.003 96.2
Kerberos 20 26 59000 32.1 0.000 96.2
Hydra 150 23 64,749 38.2 0.005 96.4
ERIS
Dysnomia 200 23 37,350 15.8 0.007 142
MAKEMAKE
S/2015 (136472) 1 175 25.2 >21,000 >12
HAUMEA
Namaka 170 21.9 25,660 18.3 0.249 113.0
Hi'iaka 310 20.6 49,880 49.5 0.051 126.4

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