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, a moon of Saturn
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 Miranda, a moon of Uranus, in 1948 and Seth Nicholson found Ananke, a moon of Jupiter, in 1951, the total count of natural planetary satellites stood at 31: Jupiter's moons numbered 12, followed by the moons of 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.

Hyperion, a moon of Saturn
Hyperion, a porous, almost loufa-like moon of Saturn was imaged during a close flyby of NASA's Cassini spacecraft.
NASA / ESA

The following tables contains all the known moons of the solar system, including the dozens of moons of Jupiter, Saturn, Uranus, and Neptune, last updated in October 2019. As of then, the count stood at 214, distributed as follows: Earth 1, Mars 2, Jupiter 79, Saturn 82, 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, the diameter of each satellite and the orbital distance from its planet's center (semimajor axis) are in kilometers; eccentricity 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.

Moons of Earth and Mars


Planet/

Satellite
Diameter
(km)
Visual
magnitude
Distance
(km)
Orbital
period (days)
Eccen-
tricity
Inclina-
tion (°)
EARTH      
Moon3,474–12.7384,40027.30.0555.1
MARS      
Phobos2211.49,3800.30.0151.1
Deimos1212.523,4601.30.0001.8

Moons of Jupiter


Satellite
Diameter
(km)
Visual
magnitude
Distance
(km)
Orbital
period (days)
Eccen-
tricity
Inclina-
tion (°)
Metis4417.5128,0000.30.0010.0
Adrastea1618.7129,0000.30.0020.1
Amalthea16814.1181,4000.50.0030.4
Thebe9816.0221,9000.70.0181.1
Io3,6435.0421,8001.80.0040.0
Europa3,1225.3671,1003.60.0090.5
Ganymede5,2624.61,070,4007.20.0010.2
Callisto4,8215.71,882,70016.70.0070.2
Themisto921.07,507,000130.00.24243.1
Leda1820.211,165,000240.90.16427.5
Himalia16014.811,461,000250.60.16227.5
Ersa322.911,483,000252.00.09430.6
Pandia323.011,525,000252.10.18028.2
Lysithea3818.211,717,000259.20.11227.7
Elara7816.611,741,000259.60.21726.6
Dia422.412,118,000287.00.21128.2
Carpo323.016,989,000456.10.43051.4
Valetudo124.018,980,000533.30.22234.0
S/2003 J12123.919,002,500433.30.376145.8
Euporie223.119,302,000550.70.144145.6
Eupheme223.420,221,000583.90.197147.6
S/2003 J18223.420,274,000588.00.105146.4
S/2010 J2123.920,307,150588.10.307150.4
S/2017 J7223.620,627,000602.60.215143.4
S/2016 J1124.020,650,850602.70.141139.8
S/2017 J3223.420,694,000606.30.148147.9
Orthosie223.120,721,000622.60.281145.9
Ananke2818.920,741,000610.00.244148.9
Euanthe322.820,799,000620.60.232148.9
Thyone422.320,940,000627.30.229148.5
S/2003 J16223.321,000,000595.40.230148.5
Mneme223.321,069,000620.00.227148.6
Harpalyke422.221,105,000623.30.226148.6
Hermippe422.121,131,000633.90.210150.7
Praxidike721.221,147,000625.30.230149.0
Thelxinoe223.521,162,000628.10.221151.4
Helike422.621,263,000634.80.156154.8
Iocaste521.821,269,000631.50.216149.4
S/2017 J9322.821,487,000639.20.229152.7
Kale223.022,407,000686.70.260165.0
S/2003 J9123.722,441,700683.00.269164.5
S/2017 J6223.522,455,000683.00.557155.2
S/2011 J1223.722,462,000686.60.233163.3
S/2003 J19223.722,757,000697.60.257166.7
Philophrosyne223.522,820,000701.30.194143.6
Eurydome322.722,865,000717.30.276150.3
Arche322.822,931,000723.90.259165.0
Autonoe422.023,039,000762.70.334152.9
Pasithee223.223,096,000719.50.267165.1
Herse223.423,097,000715.40.200164.2
Chaldene422.523,179,000723.80.251165.2
Isonoe422.523,217,000725.50.246165.2
Aitne322.723,231,000730.20.264165.1
S/2017 J5223.523,232,000719.50.284164.3
S/2017 J812423,232,700719.60.312164.7
S/2003 J4223.023,257,900723.20.204144.9
Erinome322.823,279,000728.30.266164.9
S/2017 J2223.523,303,000723.10.236166.4
S/2010 J1223.323,314,300723.20.320163.2
Taygete521.923,360,000732.20.252165.2
S/2011 J2123.623,463,900730.50.332153.6
Sponde223.023,487,000748.30.312151.0
S/2017 J1223.823,547,100734.20.397149.2
Kalyke521.823,583,000743.00.245165.2
Pasiphae5816.923,624,000708.00.409151.4
Eukelade422.623,661,000746.40.272165.5
Eirene422.523,731,800759.70.220163.1
Megaclite621.723,806,000752.80.421152.8
Carme4617.923,926,000756.10.253164.9
Sinope3818.323,939,000724.50.250158.1
Hegemone322.823,947,000739.60.328155.2
Aoede422.523,981,000761.50.432158.3
Kallichore223.724,043,000764.70.264165.5
S/2003 J23223.624,055,500759.70.309149.2
Callirrhoe720.824,102,000758.80.283147.1
S/2003 J10223.624,249,600767.00.214164.1
Cyllene223.224,349,000737.80.319149.3
Kore223.624,543,000779.20.325145.0
S/2003 J2223.228,570,000982.50.380151.8

Moons of Saturn


Satellite
Diameter
(km)
Visual
magnitude
Distance
(km)
Orbital
period (days)
Eccen-
tricity
Inclina-
tion (°)
S/2009 S10.328.0117,0000.60.0000.0
Pan2819.4133,5800.60.0000.0
Daphnis724.0136,5000.60.0030.0
Atlas3218.5137,7700.60.0010.0
Prometheus8615.8139,4300.60.0020.0
Pandora8116.4141,8100.60.0040.1
Janus17814.4151,4500.70.0100.2
Epimetheus11315.6151,4500.70.0160.4
Aegaeon0.525167,4200.80.0000.0
Mimas39712.8185,5400.90.0201.6
Methone323194,4001.00.0000.0
Anthe224.0196,9001.00.0010.2
Pallene423212,2801.20.0040.0
Enceladus49911.8238,0401.40.0000.0
Tethys1,06010.2294,6701.90.0001.1
Telesto2518.5294,7201.90.0001.2
Calypso2118.7294,7201.90.0011.5
Polydeuces423.0377,2002.70.0190.2
Dione1,11810.4377,4202.70.0020.0
Helene3118.4377,4402.70.0000.2
Rhea1,5289.6527,0704.50.0000.3
Titan5,1508.41,221,86016.00.0290.3
Hyperion28314.41,500,93021.30.0230.6
Iapetus1,43611.03,560,85079.30.0298.3
Kiviuq1422.011,384,000449.20.33246.7
Ijiraq1022.611,408,000451.40.27247.5
Phoebe22016.412,947,920548.00.163175.2
Paaliaq1921.315,204,000687.00.33246.2
Skathi623.615,635,000728.10.272152.6
S/2004 S37425.116,003,300752.90.506164.0
S/2007 S2624.416,055,000759.70.237176.7
Albiorix2620.516,393,000783.50.48034.1
Bebhionn624.117,116,000834.90.46835.1
S/2004 S31424.917,402,800853.80.24248.1
S/2004 S29424.917,470,700858.80.47244.4
Erriapus923.017,602,000871.10.47234.5
Skoll624.517,668,000878.20.464161.0
Tarqeq723.917,962,000885.20.16846.3
Siarnaq3220.118,182,000895.50.28045.8
Tarvos1322.118,243,000926.40.53833.7
S/2004 S13624.518,406,000933.50.259168.8
Hyrrokkin823.518,440,000931.90.336151.5
Greip624.418,457,000937.10.315174.8
Mundilfari623.818,653,000952.80.210167.4
S/2006 S1624.618,780,000962.20.141156.2
S/2007 S3524.918,938,000977.80.185177.6
S/2004 S20425.019,211,000990.20.204163.1
Bergelmir624.219,336,3001,005.80.142158.6
Narvi824.019,349,0001,003.90.430145.7
Jarnsaxa624.719,354,0001,006.90.218163.6
S/2004 S17425.219,448,0001,014.60.180168.2
Suttungr623.919,468,0001,016.70.114175.8
S/2004 S27424.519,776,7001,033.00.120167.1
Hati624.419,868,0001,040.20.371165.8
S/2004 S12524.819,886,0001,046.10.327165.3
Bestla723.820,209,0001,088.00.514145.1
S/2004 S22325.320,379,9001,080.40.257177.4
Farbauti524.720,390,0001,086.70.241156.5
Thrymr623.920,418,0001,092.00.466177.7
S/2004 S30325.420,424,0001,084.10.113156.3
S/2004 S25325.220,544,5001,095.00.457173.3
Aegir624.420,751,0001,117.80.252166.7
S/2004 S7624.521,000,0001,140.20.529165.7
S/2006 S3624.621,308,4001,161.50.379158.6
S/2004 S23424.821,427,0001,164.30.399177.7
S/2004 S32425.021,564,2001,175.30.262158.5
S/2004 S28424.921,791,3001,197.20.133171.0
S/2004 S35424.621,953,2001,208.10.182176.4
Kari723.922,093,0001,231.20.470152.8
Fenrir425.022,454,0001,260.40.135165.0
S/2004 S39225.522,790,4001,277.50.081167.6
Surtur624.822,941,0001,297.10.446170.0
S/2004 S38425.123,006,2001,295.80.381155.0
Loge624.623,059,0001,311.40.187167.7
Ymir1621.723,128,0001,315.10.334173.5
S/2004 S24325.223,231,3001,317.60.04936.8
S/2004 S36325.323,698,7001,354.20.667147.6
S/2004 S33425.023,764,8001,361.50.417161.5
S/2004 S21325.423,810,4001,365.10.312154.6
S/2004 S34325.324,358,9001,412.50.267165.7
Fornjot624.625,146,0001,494.10.208170.4
S/2004 S26425.026,737,8001,624.20.148171.3

Moons of Uranus


Satellite
Diameter
(km)
Visual
magnitude
Distance
(km)
Orbital
period (days)
Eccen-
tricity
Inclina-
tion (°)
Cordelia4023.649,8000.30.0000.1
Ophelia2323.353,8000.40.0100.1
Bianca5122.559,2000.40.0010.2
Cressida8021.661,8000.50.0000.0
Desdemona6422.062,7000.50.0000.1
Juliet9421.164,4000.50.0010.1
Portia13520.466,1000.50.0000.1
Rosalind7221.869,9000.60.0000.3
Cupid102674,3900.60.0010.1
Belinda8121.575,3000.60.0000.0
Perdita4023.676,4200.60.0000.5
Puck16219.886,0000.80.0000.3
Mab102697,7400.900.1
Miranda47215.8129,9001.40.0014.3
Ariel1,15813.7190,9002.50.0010.0
Umbriel1,16914.5266,0004.10.0040.1
Titania1,57813.5436,3008.70.0010.1
Oberon1,52313.7583,50013.50.0010.1
Francisco12254,282,900267.10.132147.2
Caliban8922.47,231,100579.70.181140.9
Stephano2024.18,007,400677.50.225143.8
Trinculo1025.48,505,200749.40.219167.0
Sycorax19020.812,179,4001,288.40.522159.4
Margaret1125.214,146,7001,661.00.67757.4
Prospero3020.816,267,8001,978.40.444151.2
Setebos3023.317,420,4002,225.10.591158.2
Ferdinand1225.120,430,0002,790.00.399169.8

Moons of Neptune


Satellite
Diameter
(km)
Visual
magnitude
Distance
(km)
Orbital
period (days)
Eccen-
tricity
Inclina-
tion (°)
Naiad5824.648,2300.30.0004.7
Thalassa8023.950,0700.30.0000.1
Despina14822.552,5300.30.0000.1
Galatea15822.461,9500.40.0010.0
Larissa19222.073,5500.60.0010.2
Hippocamp3426.5105,3000.90.0000.0
Proteus41620.3117,6501.10.0010.1
Triton2,70713.5354,7605.90.000156.9
Nereid34019.75,513,820360.10.7517.1
Halimede5424.216,611,0001,879.10.265112.7
Sao3125.422,228,0002,912.70.13753.5
Laomedeia372523,567,0003,171.30.40037.9
Psamathe3625.148,096,0009,074.30.380126.3
Neso4324.749,285,0009,740.70.571136.4

Moons of Pluto


Satellite
Diameter
(km)
Visual
magnitude
Distance
(km)
Orbital
period (days)
Eccen-
tricity
Inclina-
tion (°)
Charon1,18617.317,5366.40.00296.1
Styx102742,00020.20.00096.2
Nix10023.448,70824.90.00396.2
Kerberos20265900032.10.00096.2
Hydra1502364,74938.20.00596.4

Moons of Other Kuiper Belt Objects


Object/

Satellite
Diameter
(km)
Visual
magnitude
Distance
(km)
Orbital
period (days)
Eccen-
tricity
Inclina-
tion (°)
ERIS      
Dysnomia2002337,35015.80.007142
MAKEMAKE      
S/2015 (136472) 117525.2>21,000>12
HAUMEA      
Namaka17021.925,66018.30.249113.0
Hi'iaka31020.649,88049.50.051126.4

Comments


You must be logged in to post a comment.