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Moons in our Solar System

As of October 2008, there are known natural moons orbiting planets in our Solar System. moons orbit the "full-size" planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune), while moons orbit the smaller "dwarf planets" (Ceres, Pluto, Haumea, Makemake, and Eris).

year
discovered
discoverer distance from
planet (km)
diameter
(km)
orbital period
(days)
Mercury - Moons
Venus - Moons
Earth - Moon
Moon (or Luna) ? ? 384,400 3476 27.322
Mars - Moons
Deimos 1877 A. Hall 23,460 8 1.263
Phobos 1877 A. Hall 9,270 28 X 20 0.319

Jupiter - Moons
year
discovered
discoverer distance from
planet (km)
diameter
(km)
orbital period
(days)
Adrastea 1979 Jewitt & Danielson 128,980 26 X 16 0.298
Aitne 2001 S. Sheppard, D. Jewitt, & J. Kleyna 23,547,000 3 736
Amalthea 1892 E. Barnard 181,300 262 X 134 0.498
Ananke 1951 S. Nicholson 21,200,000 20 631
Aoede 2003 S. Sheppard, D. Jewitt, & J. Kleyna 23,807,655 4 748.8
Arche 2002 S. Sheppard 23,064,000 3 715.6
Autonoe 2001 S. Sheppard, D. Jewitt, & J. Kleyna 24,122,000 4 753
Callisto 1610 Galileo 1,883,000 4,800 16.689
Carme 1938 S. Nicholson 22,600,000 30 692
Callirrhoe 2000 Spacewatch Project
Minor Planet Center
24,200,000 10 774
Carpo 2003 S. Sheppard, D. Jewitt, & J. Kleyna 17,100,000 3 456.5
Chaldene 2000 S. Sheppard, D. Jewitt, Y. Fernandez, & G. Magnier 23,179,000 3.8 741
Cyllene 2003 S. Sheppard, D. Jewitt, & J. Kleyna 24,000,000 2 737.8
Elara 1905 C. Perrine 11,737,000 80 259.65
Erinome 2000 S. Sheppard, D. Jewitt, Y. Fernandez, & G. Magnier 23,279,000 3.2 672
Euanthe 2001 S. Sheppard, D. Jewitt, & J. Kleyna 21,017,000 3 622
Eukelade 2003 S. Sheppard, D. Jewitt, & J. Kleyna 24,557,295 4 746.4
Euporie 2001 S. Sheppard, D. Jewitt, & J. Kleyna 19,394,000 2 534
Europa 1610 Galileo 670,900 3126 3.551
Eurydome 2001 S. Sheppard, D. Jewitt, & J. Kleyna 23,219,000 3 713
Ganymede 1610 Galileo 1,070,000 5276 7.155
Harpalyke 2000 S. Sheppard, D. Jewitt, Y. Fernandez, & G. Magnier 21,105,000 4.3 595
Hegemone 2003 S. Sheppard, D. Jewitt, & J. Kleyna 24,514,095 3 781.6
Helike 2003 S. Sheppard, D. Jewitt, & J. Kleyna 10,972,830 4 233.8
Hermippe 2001 S. Sheppard, D. Jewitt, & J. Kleyna 21,252,000 4 630
Himalia 1904 C. Perrine 11,480,000 170 250.57
Io 1610 Galileo 421,600 3,629 1.769
Iocaste 2000 S. Sheppard, D. Jewitt, Y. Fernandez, & G. Magnier 21,269,000 5.2 657
Isonone 2000 S. Sheppard, D. Jewitt, Y. Fernandez, & G. Magnier 23,217,000 3.8 712
Kale 2001 S. Sheppard, D. Jewitt, & J. Kleyna 23,124,000 2 609
Kallichore 2003 S. Sheppard, D. Jewitt, & J. Kleyna 22,395,390 2 683.0
Kalyke 2000 S. Sheppard, D. Jewitt, Y. Fernandez, & G. Magnier 23,583,000 5.2 760
Kore 2003 S. Sheppard, D. Jewitt, & J. Kleyna 24,543,000 2 779.2
Leda 1974 C. Kowal 11,094,000 10 238.72
Lysithea 1938 S. Nicholson 11,720,000 24 259.22
Magaclite 2000 S. Sheppard, D. Jewitt, Y. Fernandez, & G. Magnier 23,806,000 5.4 771
Metis 1979 S. Sunnott 127,960 40 0.295
Mneme 2003 Scott S. Sheppard & B. Gladman 21,069,000 2 620.04
Orthosie 2001 S. Sheppard, D. Jewitt, & J. Kleyna 21,168,000 2 617
Pasiphae 1908 P. Melotte 23,500,000 36 735
Pasithee 2001 S. Sheppard, D. Jewitt, & J. Kleyna 23,029,000 2 715
Praxidike 2000 S. Sheppard, D. Jewitt, Y. Fernandez, & G. Magnier 21,147,000 6.8 632
Sinope 1914 S. Nicholson 23,700,700 28 758
Sponde 2001 S. Sheppard, D. Jewitt, & J. Kleyna 23,808,000 2 732
S/2000 J11 2000 S. Sheppard, D. Jewitt, Y. Fernandez, & G. Magnier 12,555,000 4.0 284.3
S/2003 J2 2003 S. Sheppard, D. Jewitt, & J. Kleyna 28,570,410 2 982.5
S/2003 J3 2003 S. Sheppard, D. Jewitt, & J. Kleyna 18,339,885 2 504.0
S/2003 J4 2003 S. Sheppard, D. Jewitt, & J. Kleyna 23,257,920 2 723.2
S/2003 J5 2003 S. Sheppard, D. Jewitt, & J. Kleyna 24,084,180 4 759.7
S/2003 J9 2003 S. Sheppard, D. Jewitt, & J. Kleyna 22,441,680 1 683.0
S/2003 J10 2003 S. Sheppard, D. Jewitt, & J. Kleyna 24,249,600 2 767.0
S/2003 J12 2003 S. Sheppard, D. Jewitt, & J. Kleyna 19,002,480 1 533.3
S/2003 J15 2003 S. Sheppard, D. Jewitt, & J. Kleyna 22,000,000 2 668.4
S/2003 J16 2003 S. Sheppard, D. Jewitt, & J. Kleyna 21,000,000 2 595.4
S/2003 J17 2003 S. Sheppard, D. Jewitt, & J. Kleyna 22,000,000 2 690.3
S/2003 J18 2003 S. Sheppard, D. Jewitt, & J. Kleyna 20,700,000 2 606.3
S/2003 J19 2003 S. Sheppard, D. Jewitt, & J. Kleyna 22,800,000 2 701.3
S/2003 J 23 2003 Scott S. Sheppard

23,563,000

2 732.44
Taygete 2000 S. Sheppard, D. Jewitt, Y. Fernandez, & G. Magnier 23,360,000 5.0 687
Thebe 1979 S. Synnott 221,900 100 0.675
Thelxinoe 2003 Scott S. Sheppard & B. Gladman 21,162,000 2 628.09
Themisto 1975 C. Kowal & E. Roemer 7,507,000 8 130.07
Thyone 2001 S. Sheppard, D. Jewitt, & J. Kleyna 21,312,000 4 615

Saturn - Moons
year
discovered
discoverer distance from
planet (km)
diameter
(km)
orbital period
(days)
Aegir
2005 D. Jewitt, S. Sheppard, J. Kleyna 20,735,000 6 1,116.5
Albiorix 2000 Gladman et al. 16,392,000 30 783
Anthe 2004 Cassini Imaging Team 197,700 1 1.04
Atlas 1980 R. Terrile 137,640 37 X 27 0.602
Bebhionn
2005 D. Jewitt, S. Sheppard, J. Kleyna 17,119,000 6 834.8
Bergelmir
2005 D. Jewitt, S. Sheppard, J. Kleyna 19,338,000 6 1,005.9
Bestla
2005 D. Jewitt, S. Sheppard, J. Kleyna 20,129,000 7 1,083.6
Calypso 1980 B. Smith 294,660 30 X 16 1.888

Daphnis

2005 Cassini Imaging Science Team 136,500 7 0.594
Dione 1684 G. Cassini 377,400 1120 2.737
Enceladus 1789 W. Herschel 238,020 498 1.370
Epimetheus 1966 R. Walker 151,422 138 X 110 0.694
Erriapo 2000 Intl. Team of 8 Astronomers 17,611,000 10 871.17
Farbauti
2005 D. Jewitt, S. Sheppard, J. Kleyna 20,390,000 5 1,086.1
Fenrir
2005 D. Jewitt, S. Sheppard, J. Kleyna 22,453,000 4 1,260.3
Fornjot
2005 D. Jewitt, S. Sheppard, J. Kleyna 25,108,000 6 1,490.9
Greip
2006 S. Sheppard, D. Jewitt, J. Kleyna 18,206,000 6 921.2
Hati
2005 D. Jewitt, S. Sheppard, J. Kleyna 19,856,000 6 1,038.7
Helene 1980 Laques & Lecacheux 377,400 36 X 28 2.737
Hyperion 1848 W. Bond 1,481,000 360 X 226 21.277
Hyrokkin
2006 S. Sheppard, D. Jewitt, J. Kleyna 18,437,000 8 931.8
Iapetus 1671 G. Cassini 3,561,300 1436 79.3215
Ijiraq 2000 Intl. Team of 8 Astronomers 11,440,000 14 451.48
Janus 1966 A. Dollfus 151,472 190 X 154 0.695
Jarnsaxa
2006 S. Sheppard, D. Jewitt, J. Kleyna 18,811,000 6 964.7
Kari
2006 S. Sheppard, D. Jewitt, J. Kleyna 22,118,000 7 1,233.6
Kiviuq 2000 Intl. Team of 8 Astronomers 11,365,000 17 449.22
Loge
2006 S. Sheppard, D. Jewitt, J. Kleyna 23,065,000 6 1,312.0
Methone 2004 C.C. Porco et al./Cassini 194,000 3 1.01
Mimas 1789 W. Herschel 185,520 398 0.942
Mundilfari 2000 Intl. Team of 8 Astronomers 18,709,000 7 951.38
Narvi 2003 Scott S. Sheppard, David Jewitt, and Jan Kleyna 18,719,000 8 956.2
Paaliaq 2000 Intl. Team of 8 Astronomers 15,199,000 25 686.92
Pallene 2004 C.C. Porco et al./Cassini 211,000 4 1.14
Pan 1990 M. Showalter 133,630 19.32 0.5750
Pandora 1980 S. Collins 141,700 110 X 62 0.629
Phoebe 1898 W. Pickering 12,952,000 220 550.48
Polydeuces 2004 C.C. Porco et al./Cassini 377,400 4 2.74
Prometheus 1980 S. Collins 139,350 148 X 68 0.613
Rhea 1672 G. Cassini 527,040 1528 4.518
Siarnaq 2000 Intl. Team of 8 Astronomers 18,160,000 45 893.07
Skathi 2000 Intl. Team of 8 Astronomers 15,645,000 8 728.93
Skoll
2006 S. Sheppard, D. Jewitt, J. Kleyna 17,665,000 6 878.3

Surtur

2006 S. Sheppard, D. Jewitt, J. Kleyna 22,707,000 6 1,297.7
Suttungr 2000 Gladman et al. 19,470,000 7 1016.8
S/2004 S07
2004 D. Jewitt, S. Sheppard, J. Kleyna 19,800,000 6 1,103
S/2004 S12
2004 D. Jewitt, S. Sheppard, J. Kleyna 19,650,000 5 1,048
S/2004 S13
2004 D. Jewitt, S. Sheppard, J. Kleyna 18,450,000 6 906
S/2004 S17
2004 D. Jewitt, S. Sheppard, J. Kleyna 18,600,000 4 986
S/2006 S1
2006 S. Sheppard, D. Jewitt, J. Kleyna 18,981,135 6 970
S/2006 S3
2006 S. Sheppard, D. Jewitt, J. Kleyna 21,132,000 6 1,142
S/2007 S2
2007 S. Sheppard, D. Jewitt, J. Kleyna 16,560,000 6 800
S/2007 S3
2007 S. Sheppard, D. Jewitt, J. Kleyna 20,518,500 5 1,100
Tarqeq
2007 S. Sheppard, D. Jewitt, J. Kleyna 18,009,000 7 887.5
Tarvos 2000 Intl. Team of 8 Astronomers 18,239,000 16 925.70
Telesto 1980 B. Smith 294,660 30 X 16 1.888
Tethys 1684 G. Cassini 294,660 1060 1.888
Thrymr 2000 Intl. Team of 8 Astronomers 20,470,000 7 1088.89
Titan 1655 C. Huygens 1,221,850 5150 15.945
Ymir 2000 Intl. Team of 8 Astronomers 23,096,000 20 1312.37

Uranus - Moons
year
discovered
discoverer distance from
planet (km)
diameter
(km)
orbital period
(days)
Ariel 1851 W. Lassell 191,240 1160 2.520
Belinda 1986 Voyager 2 75,260 66 0.624
Bianca 1986 Voyager 2 75,260 42 0.433
Caliban 1997 Gladman, Nicholson, Burns, & Kavelaars 7,200,000 80 579.5
Cordelia 1986 Voyager 2 49,750 26 0.335
Cressida 1986 Voyager 2 61,770 62 0.464
Cupid 2003 M. Showalter & J. Lissauer 74,800 12 0.618
Desdemona 1986 Voyager 2 62,660 54 0.474
Ferdinand 2001 M. Holman & B. Gladman et al 20,901,000 21 2,823.4
Francisco 2001 M. Holman & B. Gladman et al 4,276,000 22 266.6
Juliet 1986 Voyager 2 64,360 84 0.493
Mab 2003 M. Showalter & J. Lissauer 97,734 16 0.923
Margaret 2003 S. Sheppard 14,688,700 11 1,694.8
Miranda 1948 G. Kuiper 129,780 472 1.414
Oberon 1787 W. Herschel 582,600 1526 13.463
Ophelia 1986 Voyager 2 53,440 30.4 0.3764
Perdita 1986 E. Karkoschka/Voyager 2 76,420 20 0.638
Portia 1986 Voyager 2 66,085 108 0.513
Prospero 1999 Kavelaars, Gladman, Holman et al 16,256,000 30 5.346
Puck 1985 Voyager 2 86,010 154 0.762
Rosalind 1986 Voyager 2 69,941 54 0.558
Setebos 1999 Kavelaars, Gladman, Holman et al 17,418,000 47 2,234.8
Stephano 1999 Kavelaars, Gladman, Holman et al 8,004,000 32 677.4
Sycorax 1997 Gladman, Nicholson, Burns, & Kavelaars 12,200,000 160 1283.39
Titania 1787 W. Herschel 435,840 1,578 8.706
Trinculo 2001 M. Holman, J. Kavelaars & D. Milisavljevic 8,578,000 10 759.0
Umbriel 1851 W. Lassel 265,970 1190 4.144

Neptune - Moons
year
discovered
discoverer distance from
planet (km)
diameter
(km)
orbital period
(days)
Despina 1989 Voyager 2 62,000 160 0.40
Galatea 1989 Voyager 2 52,500 140 0.33
Halimede 2002 M. Holman & J.J. Kavelaars 15,686,000 60 1,874.83
Larissa 1989 Voyager 2 73,600 200 0.56
Laomedeia 2002 M. Holman & J.J. Kavelaars 22,613,200 38 2,980.4
Naiad 1989 Voyager 2 48,200 50 0.30
Nereid 1949 G. Kuiper 5,513,400 340 360.16
Neso 2002 Holman & Gladman et al 47,279,670 60 9,007.1
Proteus 1989 Voyager 2 117,600 420 1.12
Psamathe 2003 D. Jewitt, J. Kleyna & S. Sheppard 46,738,000 38 9,136.11
Sao 2002 M. Holman & J.J. Kavelaars 22,337,190 38 2,925.6
Thalassa 1989 Voyager 2 50,000 90 0.31
Triton 1846 W. Lassel 354,800 2705 5.877

Dwarf Planets

Ceres - 0 Moons

Pluto - Moons
year
discovered
discoverer distance from
planet (km)
diameter
(km)
orbital period
(days)
Charon 1978 J. Christy 19,571 1,207 6.387
Nix 2005 H.A. Weaver, S.A. Stern, et al. 48,675 44-130 24.856
Hydra 2005 H.A. Weaver, S.A. Stern, et al. 64,780 44-130 38.206

Haumea - Moons
year
discovered
discoverer distance from
planet (km)
diameter
(km)
orbital period
(days)
Namaka 2005 H.A. Weaver, S.A. Stern, et al. ~39,000 ~170 34.7
Hi'iaka 2005 H.A. Weaver, S.A. Stern, et al. 49,500 ~310 49.12

Makemake - 0 Moons

Eris - Moon
year
discovered
discoverer distance from
planet (km)
diameter
(km)
orbital period
(days)
Dysnomia 2005 M. Brown, M. van Dam, A. Bouches, D. Le Mignant 30,000-36,000 ~300 ~14

Last modified October 9, 2008 by Randy Russell.

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