Moons of Saturn

The planet Saturn has 274 moons with confirmed and stable orbits. Sixty-three of these have officially been named, after Titans, Giants, or minor Greek or Roman gods.[1] Most of these moons are very small: 248 of the above total are less than 10 km (6 mi) in diameter.[2] Saturn also has many moonlets, extremely tiny particles within Saturn's rings that orbit the planet.

Confirmed moons

The moons of Saturn that were announced by 2018 are listed here by orbital period (or semi-major axis), from shortest to longest. Moons massive enough for their surfaces to have collapsed into a spheroid are highlighted in bold, while the irregular moons are listed in red, orange and gray background.
Key
†
Major icy moons		 ♠
Titan		 ‡
Inuit group		 ♦
Gallic group		 ♣
Norse group
Order Label
[a]		 Name Pronunciation Image Diameter (km)[b] Mass
(×1015 kg) [c]		 Semi-major axis (km) [d] Orbital period (d)[d][e] Inclination [d][f] Eccentricity Position Discovery
year		 Discoverer
1 S/2009 S 1—≈ 0.3< 0.0001≈ 117000≈ 0.47≈ 0°≈ 0outer B Ring2009Cassini
(moonlets)—A noisy image showing a few bright dots marked by circles0.04 to 0.4 (Earhart)< 0.0001≈ 130000≈ 0.55≈ 0°≈ 0Three 1000 km bands within A Ring2006Cassini
2XVIII Pan/ˈpæn/A bright fuzzy band (rings of Saturn) is running from the left to right. In the center a bright irregularity shaped body is superimposed on its upper edge. A narrow grayish band, which is a part of the main band, partially covers the body.28.2±2.6
(34 × 31 × 20)		4.95±0.75133584+0.575050.001°0.000035in Encke Division1990M. Showalter
3XXXV Daphnis/ˈdæfnɪs/Two bright bands run from the left to right. In the narrow gap between them (Keeler gap), which has wavy edges, a small oblong object can be seen.7.6±1.6
(9 × 8 × 6)		0.084±0.012136505+0.59408≈ 0°≈ 0in Keeler Gap2005Cassini
4XV Atlas/ˈætləs/An irregularly shaped body is fully illuminated. The body, which looks like a cone viewed from the south pole, is elongated downward.30.2±1.8
(41 × 35 × 19)		6.6±0.045137670+0.601690.003°0.0012outer A Ring shepherd1980Voyager 2
5XVI Prometheus/proʊˈmiːθiəs/An irregularly shaped oblong body is fully illuminated. It is elongated in the direction from the right to left. Its surface is covered by craters. There is valley at the top.86.2±5.4
(136 × 79 × 59)		159.5±1.5139380+0.612990.008°0.0022inner F Ring shepherd1980Voyager 2
6XVII Pandora/pænˈdɔːrə/An irregularly shaped body is half illuminated from the bottom. The terminator runs from the left to right. The surface is covered by numerous craters.81.4±3.0
(104 × 81 × 64)		137.1±1.9141720+0.628500.050°0.0042outer F Ring Shepherd1980Voyager 2
7aXI Epimetheus/ɛpɪˈmiːθiəs/A partially-illuminated irregular body, which has a shape remotely resembling a cube. The body's surface consists of ridges and valleys and is covered by craters.116.2±3.6
(130 × 114 × 106)		526.6±0.6151422+0.694330.335°0.0098co-orbital with Janus1977J. Fountain, and S. Larson
7bX Janus/ˈdʒeɪnəs/An irregular body, whose outline looks like an approximate circle in this image. It is illuminated from the bottom-left. The terminator runs from the top-left to bottom-right. The surface is covered by craters.179.0±2.8
(203 × 185 × 153)		1897.5±0.6151472+0.694660.165°0.0068co-orbital with Epimetheus1966A. Dollfus
9LIII Aegaeon/iːˈdʒiːən/Image of Aegaeon.≈ 0.5≈ 0.0001167500+0.808120.001°0.0002G Ring moonlet2008Cassini
10I †Mimas/ˈmaɪməs/A spherical body is half illuminated from the left. The terminator runs from the top to bottom in the vicinity of the right limb. A large crater with a central peak sits on the terminator slightly to the right and above the center of the body. It makes the body look like the Death Star. There are numerous smaller craters.396.4±0.8
(416 × 393 × 381)		37493±31185404+0.9424221.566°0.0202 1789W. Herschel
11XXXII Methone/mɪˈθoʊniː/From May 2012 flyby3.2±1.2≈ 0.02194440+1.009570.007°0.0001Alkyonides2004Cassini
12XLIX Anthe/ˈænθiː/1.8≈ 0.0015197700+1.050890.1°0.0011Alkyonides2007Cassini
13XXXIII Pallene/pəˈliːniː/In the center is Pallene, a moon of Saturn5.0±1.2
(6 × 6 × 4)		≈ 0.05212280+1.153750.181°0.0040Alkyonides2004Cassini
14II †Enceladus/ɛnˈsɛlədəs/A spherical body is half illuminated from the right. The terminator runs from the top to bottom in the vicinity of the left limb. In the center and at the top there are heavily cratered areas.504.2±0.4
(513 × 503 × 497)		108022±101237950+1.3702180.010°0.0047Generates the E ring1789W. Herschel
15III †Tethys/ˈtiːθɪs/A spherical heavily cratered body is illuminated from the bottom. The terminator runs from the left to right in the vicinity of the top limb. There is a wide curved graben running from the center of the body to the bottom. It is Ithaca Chasma.1062±1.2
(1077 × 1057 × 1053)		617449±132294619+1.8878020.168°0.0001 1684G. Cassini
15aXIII Telesto/tɪˈlɛstoʊ/24.8±0.8
(33 × 24 × 20)		≈ 9.41294619+1.8878021.158°0.000leading Tethys trojan1980B. Smith, H. Reitsema, S. Larson, and J. Fountain
15bXIV Calypso/kəˈlɪpsoʊ/An oblong reddish body is seen in this low resolution image.21.4±1.4
(30 × 23 × 14)		≈ 6.3294619+1.8878021.473°0.000trailing Tethys trojan1980D. Pascu, P. Seidelmann, W. Baum, and D. Currie
18IV †Dione/daɪˈoʊniː/A spherical body is half illuminated from the right. The terminator is running from the top to bottom slightly to the left off the center. The central part of the body is smooth and has only a few craters. A heavily cratered terrain is near the right limb. A part of a large crater is intersected by the terminator in the lower-left corner. To the left of it there is a long crack running parallel to the terminator.1122.8±0.8
(1128 × 1123 × 1119)		1095452±168377396+2.7369150.002°0.0022 1684G. Cassini
18aXII Helene/ˈhɛlɪniː/An irregularly shaped body illuminated from the left. Its surface is covered by numerous impact craters.35.2±0.8
(43 × 38 × 26)		≈ 24.46377396+2.7369150.212°0.0022leading Dione trojan1980P. Laques and J. Lecacheux
18bXXXIV Polydeuces/pɒliˈdjuːsiːz/A small oblong body is barely resolved in this image.2.6±0.8
(3 × 2 × 1)		≈ 0.03377396+2.7369150.177°0.0192trailing Dione trojan2004Cassini
21V †Rhea/ˈriːə/A spherical body is almost fully illuminated. The terminator is running near the top edge. The surface is covered by numerous craters. Two partially overlapping large craters can be seen above the center. One that is younger is above and to the right from the older one.1527.0±1.2
(1530 × 1526 × 1525)		2306518±353527108+4.5182120.327°0.001258 1672G. Cassini
22VI ♠Titan/ˈtaɪtən/An orange spherical body is half illuminated from the right. The terminator is running from the top to bottom slightly to the left off the center. Both limb and terminator are fuzzy due to light scattering in the atmosphere.5149.46±0.18
(5149 × 5149 × 5150)		134520000±200001221930+15.945420.3485°0.0288 1655C. Huygens
23VII †Hyperion/haɪˈpɪəriən/An irregularly shaped oblong body is illuminated from the left. The terminator is near the right limb. The body is elongated in the top-bottom direction. The surface is punctured by numerous impact craters, which make it look like a sponge or cheese.270±8
(360 × 266 × 205)		5620±501481010+21.276610.568°0.123006in 4:3 resonance with Titan1848W. Bond
G. Bond
W. Lassell
24VIII †Iapetus/aɪˈæpɪtəs/A walnut shaped body illuminated from the bottom-left. The terminator runs from the top to right along the top-right limb. An equatorial ridge runs from the left to right and is convex in the direction of the bottom-left. Above and below it there are dark areas. Above the upper dark area and below the lower one there are bright poles. There numerous craters. Three among them are very large: one sits on the limb at the right another is in the center above the ridge. The third is below the ridge near the left limb.1468.6±5.6
(1491 × 1491 × 1424)		1805635±3753560820+79.321515.47°0.028613 1671G. Cassini
25XXIV ‡Kiviuq/ˈkɪviək/≈ 16≈ 2.7911294800+448.1649.087°0.3288Inuit group2000B. Gladman, J. Kavelaars, et al.
26XXII ‡Ijiraq/ˈiːɪrɒk/≈ 12≈ 1.1811355316+451.7750.212°0.3161Inuit group2000B. Gladman, J. Kavelaars, et al.
27IX ♣†Phoebe/ˈfiːbiː/An approximately spherical heavily cratered body is illuminated from the bottom-right. The terminator runs near the left and top limbs. There is huge crater at the top, which affects the shape, and another slightly smaller at the bottom.213.0±1.4
(219 × 217 × 204)		8292±1012869700−545.09173.047°0.156242Norse group1899W. Pickering
28XX ‡Paaliaq/ˈpɑːliɒk/≈ 22≈ 7.2515103400+692.9846.151°0.3631Inuit group2000B. Gladman, J. Kavelaars, et al.
29XXVII ♣Skathi/ˈskɒði/≈ 8≈ 0.3515672500−732.52149.084°0.246Norse (Skathi) Group2000B. Gladman, J. Kavelaars, et al.
30XXVI ♦Albiorix/ˌælbiˈɒrɪks/≈ 32≈ 22.316266700+774.5838.042°0.477Gallic group2000M. Holman
31  ♣S/2007 S 2—≈ 6≈ 0.1516560000−792.96176.68°0.2418Norse group2007S. Sheppard, D. Jewitt, J. Kleyna, B. Marsden
32XXXVII ♦Bebhionn/bɛˈviːn/≈ 6≈ 0.1517153520+838.7740.484°0.333Gallic group2004S. Sheppard, D. Jewitt, J. Kleyna
33XXVIII ♦Erriapus/ɛriˈæpəs/≈ 10≈ 0.6817236900+844.8938.109°0.4724Gallic group2000B. Gladman, J. Kavelaars, et al.
34XLVII ♣Skoll/ˈskɒl/≈ 6≈ 0.1517473800−862.37155.624°0.418Norse (Skathi) group2006S. Sheppard, D. Jewitt, J. Kleyna
35XXIX ‡Siarnaq/ˈsiːɑːrnək/≈ 40≈ 43.517776600+884.8845.798°0.24961Inuit group2000B. Gladman, J. Kavelaars, et al.
36LII ‡Tarqeq/ˈtɑːrkeɪk/≈ 7≈ 0.2317910600+894.8649.904°0.1081Inuit group2007S. Sheppard, D. Jewitt, J. Kleyna
37  ♣S/2004 S 13—≈ 6≈ 0.1518056300−905.85167.379°0.261Norse group2004S. Sheppard, D. Jewitt, J. Kleyna
38LI ♣Greip/ˈɡreɪp/≈ 6≈ 0.1518065700−906.56172.666°0.3735Norse group2006S. Sheppard, D. Jewitt, J. Kleyna
39XLIV ♣Hyrrokkin/hɪˈrɒkɪn/≈ 8≈ 0.3518168300−914.29153.272°0.3604Norse (Skathi) group2006S. Sheppard, D. Jewitt, J. Kleyna
40L ♣Jarnsaxa/jɑːrnˈsæksə/≈ 6≈ 0.1518556900−943.78162.861°0.1918Norse group2006S. Sheppard, D. Jewitt, J. Kleyna
41XXI ♦Tarvos/ˈtɑːrvəs/≈ 15≈ 2.318562800+944.2334.679°0.5305Gallic group2000B. Gladman, J. Kavelaars, et al.
42XXV ♣Mundilfari/mʊndəlˈværi/≈ 7≈ 0.2318725800−956.70169.378°0.198Norse group2000B. Gladman, J. Kavelaars, et al.
43  ♣S/2006 S 1—≈ 6≈ 0.1518930200−972.41154.232°0.1303Norse (Skathi) group2006S. Sheppard, D.C. Jewitt, J. Kleyna
44  ♣S/2004 S 17—≈ 4≈ 0.0519099200−985.45166.881°0.226Norse group2004S. Sheppard, D. Jewitt, J. Kleyna
45XXXVIII ♣Bergelmir/bɛərˈjɛlmɪər/≈ 6≈ 0.1519104000−985.83157.384°0.152Norse (Skathi) group2004S. Sheppard, D. Jewitt, J. Kleyna
46XXXI ♣Narvi/ˈnɑːrvi/≈ 7≈ 0.2319395200−1008.45137.292°0.320Norse (Narvi) group2003S. Sheppard, D. Jewitt, J. Kleyna
47XXIII ♣Suttungr/ˈsʊtʊŋɡər/≈ 7≈ 0.2319579000−1022.82174.321°0.131Norse group2000B. Gladman, J. Kavelaars, et al.
48XLIII ♣Hati/ˈhɑːti/≈ 6≈ 0.1519709300−1033.05163.131°0.291Norse group2004S. Sheppard, D. Jewitt, J. Kleyna
49  ♣S/2004 S 12—≈ 5≈ 0.0919905900−1048.54164.042°0.396Norse group2004S. Sheppard, D. Jewitt, J. Kleyna
50XL ♣Farbauti/fɑːrˈbaʊti/≈ 5≈ 0.0919984800−1054.78158.361°0.209Norse (Skathi) group2004S. Sheppard, D. Jewitt, J. Kleyna
51XXX ♣Thrymr/ˈθrɪmər/≈ 7≈ 0.2320278100−1078.09174.524°0.453Norse group2000B. Gladman, J. Kavelaars, et al.
52XXXVI ♣Aegir/ˈaɪ.ɪər/≈ 6≈ 0.1520482900−1094.46167.425°0.237Norse group2004S. Sheppard, D. Jewitt, J. Kleyna
53  ♣S/2007 S 3—≈ 5≈ 0.0920518500≈ −1100177.22°0.130Norse group2007S. Sheppard, D. Jewitt, J. Kleyna
54XXXIX ♣Bestla/ˈbɛstlə/≈ 7≈ 0.2320570000−1101.45147.395°0.5145Norse (Narvi) group2004S. Sheppard, D. Jewitt, J. Kleyna
55  ♣S/2004 S 7—≈ 6≈ 0.1520576700−1101.99165.596°0.5299Norse group2004S. Sheppard, D. Jewitt, J. Kleyna
56  ♣S/2006 S 3—≈ 6≈ 0.1521076300−1142.37150.817°0.4710Norse (Skathi) group2006S. Sheppard, D. Jewitt, J. Kleyna
57XLI ♣Fenrir/ˈfɛnrɪər/≈ 4≈ 0.0521930644−1212.53162.832°0.131Norse group2004S. Sheppard, D. Jewitt, J. Kleyna
58XLVIII ♣Surtur/ˈsɜːrtər/≈ 6≈ 0.1522288916−1242.36166.918°0.3680Norse group2006S. Sheppard, D. Jewitt, J. Kleyna
59XLV ♣Kari/ˈkɑːri/≈ 7≈ 0.2322321200−1245.06148.384°0.3405Norse (Skathi) group2006S. Sheppard, D. Jewitt, J. Kleyna
60XIX ♣Ymir/ˈɪmɪər/≈ 18≈ 3.9722429673−1254.15172.143°0.3349Norse group2000B. Gladman, J. Kavelaars, et al.
61XLVI ♣Loge/ˈlɔɪ.eɪ/≈ 6≈ 0.1522984322−1300.95166.539°0.1390Norse group2006S. Sheppard, D. Jewitt, J. Kleyna
62XLII ♣Fornjot/ˈfɔːrnjɒt/≈ 6≈ 0.1524504879−1432.16167.886°0.186Norse group2004S. Sheppard, D. Jewitt, J. Kleyna

Unconfirmed moons

The following objects (observed by Cassini) have not been confirmed as solid bodies. It is not yet clear if these are real satellites or merely persistent clumps within the F Ring.

Name Image Diameter (km) Semi-major
axis (km)		 Orbital
period (d)		 Position Discovery year
S/2004 S 6A bright narrow band runs from the top to bottom. To the right of it in the diffuse halo the is a bright small object.≈ 3–5≈ 140130+0.61801uncertain objects around the F Ring2004
S/2004 S 3/S 4[g]≈ 3–5≈ 140300≈ +0.6192004

Hypothetical moons

Two moons were claimed to be discovered by different astronomers but never seen again. Both moons were said to orbit between Titan and Hyperion.

  • Chiron which was supposedly sighted by Hermann Goldschmidt in 1861, but never observed by anyone else.
  • Themis was allegedly discovered in 1905 by astronomer William Pickering, but never seen again. Nevertheless, it was included in numerous almanacs and astronomy books until the 1960s.

See Also

List Of Natural Satellites

References

Citations


  1. ↑ "Saturn: Moons". Solar System Exploration: Planets. National Aeronautics and Space Administration. 2011. Archived from the original on 2011-03-16. Retrieved 2011-04-21.
  2. ↑ "About Saturn & Its Moons". Cassini Solstice Mission. National Aeronautics and Space Administration. 2011. Retrieved 2011-06-25.

Notes

  1. ↑ A confirmed moon is given a permanent designation by the IAU consisting of a name and a Roman numeral. The nine moons that were known before 1900 (of which Phoebe is the only irregular) are numbered in order of their distance from Saturn; the rest are numbered in the order by which they received their permanent designations. Nine small moons of the Norse group and S/2009 S 1 have not yet received a permanent designation.
  2. ↑ The diameters and dimensions of the inner moons from Pan through Janus, Methone, Pallene, Telepso, Calypso, Helene, Hyperion and Phoebe were taken from Thomas 2010, Table 3. Diameters and dimensions of Mimas, Enceladus, Tethys, Dione, Rhea and Iapetus are from Thomas 2010, Table 1. The approximate sizes of other satellites are from the website of Scott Sheppard.
  3. ↑ Masses of the large moons were taken from Jacobson, 2006. Masses of Pan, Daphnis, Atlas, Prometheus, Pandora, Epimetheus, Janus, Hyperion and Phoebe were taken from Thomas, 2010, Table 3. Masses of other small moons were calculated assuming a density of 1.3 g/cm3.
  4. 1 2 3 The orbital parameters were taken from Spitale, et al. 2006, IAU-MPC Natural Satellites Ephemeris Service, and NASA/NSSDC.
  5. ↑ Negative orbital periods indicate a retrograde orbit around Saturn (opposite to the planet's rotation).
  6. ↑ To Saturn's equator for the regular satellites, and to the ecliptic for the irregular satellites
  7. ↑ S/2004 S 4 was most likely a transient clump—it has not been recovered since the first sighting.
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