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Object Provisional Semi-Major Axis Diameter
Designation Comments or Radius (km)
 
Mercury (total moons): 0
Mercury Equator                    2,440         4,880
     
     
Venus (total moons): 0    
Venus Equator                  6,052       12,104
     
     
Earth (total moons): 1    
Earth Equator                  6,378       12,756
Moon              384,400         3,475
     
     
Mars (total moons):  2    
Mars Equator                  3,397         6,794
Phobos                  9,380              22
Deimos                23,460              12
Ceres (total moons): 0
Ceres Equator:                     425            850
         
Jupiter (total moons): 69        
Jupiter Equator                71,492      142,984
Halo ring inner edge 1979 J1R              100,000    
Halo ring outer edge 1979 J1R              122,000    
Main ring inner edge 1979 J2R              122,000    
Metis S/1979 J3 Amalthea Group              127,690              43
Adrastea S/1979 J1 Amalthea Group              128,690              16
Main ring outer edge 1979 J2R              129,000    
Inner Gossamer ring - inner edge 1979 J3R              129,200    
Amalthea V Amalthea Group              181,366            167
Inner Gossamer ring outer edge 1979 J3R              182,000    
Outer Gossamer ring inner edge              182,000    
Thebe S/1979 J2 Amalthea Group              221,889              99
Outer Gossamer ring outer edge              224,900    
Io I  Galilean              421,700         3,643
Europa II Galilean              671,034         3,122
Ganymede III Galilean            1,070,412         5,262
Callisto IV Galilean            1,882,709         4,821
Themisto S/1975 J1 Themisto Group            7,393,216               8
Leda XIII Himalia Group          11,187,781              20
Himalia VI Himalia Group          11,451,971            170
Lysithea X Himalia Group          11,740,560              36
Elara VII Himalia Group          11,778,034              86
S/2000 J11 S/2000 J11 Himalia Group          12,570,424               4
Carpo S/2003 J20 (?)          17,144,873               3
S/2003 J12 S/2003 J12 (?)          17,739,539               1
Euporie S/2001 J10 Ananke Group (?)          19,088,434               2
S/2003 J3 S/2003 J3 Ananke Group (?)          19,621,780               2
S/2003 J18 S/2003 J18 Ananke Group (?)          19,812,577               2
S/2011 J1 S/2011 J1          20,155,290               1
S/2010 J2 S/2010 J2          20,252,743               1
Thelxinoe S/2003 J22 Ananke Group (?)          20,453,753               2
Euanthe S/2001 J7 Ananke Group          20,464,854               3
Helike S/2003 J6 Ananke Group (?)          20,540,266               4
Orthosie S/2001 J9 Ananke Group (?)          20,567,971               2
S/2016 J1     S2016 J1   20,595,487    2   
Iocaste S/2000 J3 Ananke Group          20,722,566               5
S/2003 J16 S/2003 J16 Ananke Group          20,743,779               2
Praxidike S/2000 J7 Ananke Group          20,823,948               7
Harpalyke S/2000 J5 Ananke Group          21,063,814               4
Mneme S/2003 J21 Ananke Group          21,129,786               2
Hermippe S/2001 J3 Ananke Group (?)          21,182,086               4
Thyone S/2001 J2 Ananke Group          21,405,570               4
Ananke XII Ananke Group          21,454,952              16
Herse S/2003 J17 Carme Group          22,134,306               2
Aitne S/2001 J11 Carme Group          22,285,161               3
Kale S/2001 J8 Carme Group          22,409,207               2
Taygete S/2000 J9 Carme Group          22,438,648               5
S/2003 J19 S/2003 J19 Carme Group          22,709,061               2
Chaldene S/2000 J10 Carme Group          22,713,813               4
S/2003 J15 S/2003 J15 Ananke Group (?)          22,720,999               2
S/2003 J10 S/2003 J10 Carme Group (?)          22,730,813               2
S/2003 J23 S/2003 J23 Pasiphae Group          22,739,654               2
Erinome S/2000 J4 Carme Group          22,986,266               3
Aoede S/2003 J7 Pasiphae Group          23,044,175               4
Kallichore S/2003 J11 Carme Group (?)          23,111,823               2
Kalyke S/2000 J2 Carme Group          23,180,773               5
Carme XI Carme Group          23,197,992              46
Callirrhoe S/1999 J1 Pasiphae Group          23,214,986               9
Eurydome S/2001 J4 Pasiphae Group (?)          23,230,858               3
S/2010 J1 S/2010 J1          23,251,837               2
Pasithee S/2001 J6 Carme Group          23,307,318               2
S/2011 J2 S/2011 J2          23,329,710               1
Kore S/2003 J14 Pasiphae Group          23,345,093               2
Cylene S/2003 J13 Pasiphae Group          23,396,269               2
Eukelade S/2003 J1 Carme Group          23,483,694               4
S/2017 J1     S/2017 J1   23,483,983    2   
S/2003 J4 S/2003 J4 Pasiphae Group          23,570,790               2
Pasiphae VIII Carme Group          23,609,042              60
Hegemone S/2003 J8 Pasiphae Group          23,702,511               3
Arche S/2002 J1 Carme Group          23,717,051               3
Isonoe S/2000 J6 Carme Group          23,800,647               4
S/2003 J9 S/2003 J9 Carme Group          23,857,808               1
S/2003 J5 S/2003 J5 Carme Group          23,973,926               4
Sinope IX Pasiphae Group          24,057,865              38
Sponde S/2001 J5 Pasiphae Group          24,252,627               2
Autonoe S/2001 J1 Pasiphae Group          24,264,445               4
Megaclite S/2000 J8 Pasiphae Group          24,687,239               5
S/2003 J2 S/2003 J2 (?)          30,290,846               2
         
         
Saturn (total moons):   62        
Saturn Equator                60,268      120,536
D ring inner edge                66,900    
D ring outer edge                74,510    
C ring inner edge                74,658    
Columbo Gap - inner edge                  77,800    
Columbo Gap - outer edge                77,900    
Maxwell Gap - inner edge                87,500    
Maxwell Gap - outer edge                87,770    
Bond Gap - inner edge                88,690    
Bond Gap - outer edge                88,720    
Dawes Gap - inner edge                90,200    
Dawes Gap - outer edge                90,220    
C ring outer edge                92,000    
B ring inner edge                92,000    
S/2009 S1 S/2009 S1 In B Ring              117,000             0.3
B ring outer edge              117,580    
Cassini Division - inner edge              117,580    
Huygens Gap - inner edge              117,680    
Huygens Gap - outer edge              118,120    
Herschel Gap - inner edge              118,183    
Herschel Gap - outer edge              118,285    
Russell Gap - inner edge              118,597    
Russell Gap - outer edge              118,630    
Jeffreys Gap - inner edge              118,931    
Jeffreys Gap - outer edge              118,969    
Kuiper Gap - inner edge              119,403    
Kuiper Gap - outer edge              119,406    
Laplace Gap - inner edge              119,848    
Laplace Gap - outer edge              120,086    
Bessel Gap - inner edge              120,236    
Bessel Gap - outer edge              120,246    
Barnard gap - inner edge              120,305    
Barnard Gap - outer edge              120,318    
Cassini Division - outer edge              122,170    
A ring inner edge              122,170    
Encke Gap - inner edge              133,570    
Pan S/1981 S13 In Encke Division              133,583              26
Encke Gap - outer edge              133,895    
Daphnis S/2005 S1 In Keeler Gap              136,505               7
Keeler Gap - inner edge              136,530    
Keeler Gap - outer edge              136,565    
A ring outer edge              136,775    
Roche Division - inner edge              136,775    
Atlas S/1980 S28 Outer A Ring Shepherd              137,700              20
Roche Division - outer edge              139,380    
Prometheus S/1980 S27 Inner F Ring Shepherd              139,400              94
F Ring - inner edge Eccentric; clumped              140,180    
F Ring - outer edge Eccentric; clumped              140,244    
Pandora S/1980 S26 Outer F Ring Shepherd              141,700              81
Janus-Epimetheus Ring - inner edge              149,000    
Epimetheus S/1980 S3 Coorbital w/ Janus              151,400            117
Janus S/1980 S1 Coorbital w/ Epimetheus              151,500            181
Janus-Epimetheus Ring - outer edge              154,000    
Aegaeon S/2008 S1 Embedded in G Ring              167,500           0.25
G ring inner edge              170,000    
G ring outer edge              175,000    
E ring inner edge              181,000    
Mimas I               185,600            397
Methone S/2004 S1              194,000               3
R/2006 S5              194,000    
Anthe S/2007 S4              197,700               4
Pallene Ring - inner edge              211,000    
Pallene S/2004 S2              211,000               4
Pallene Ring - outer edge              213,500    
Enceladus II              238,100            499
Tethys III              294,700         1,060
Telesto S/1980 S13 Leading Tethys Trojan              294,700              24
Calypso S/1980 S25 Trailing Tethys Trojan              294,700              19
Dione IV              377,400         1,120
Helene S/1980 S6 Leading Dione Trojan              377,400              32
Polydeuces S/2004 S5 Trailing Dione Trojan              377,400               4
E ring outer edge              483,000    
Rhea V               527,100         1,528
Titan VI            1,221,900         5,151
Hyperion VII            1,464,100            266
Iapetus VIII            3,560,800         1,460
Phobe ring inner edge            6,000,000    
Kiviuq S/2000 S5 Inuit Group          11,110,000              14
Ijiraq S/2000 S6 Inuit Group          11,125,000              10
Phoebe ring outer edge          12,000,000    
Phoebe IX Norse Group          12,944,300            215
Paaliaq S/2000 S2 Inuit Group          15,200,000              19
Skathi S/2000 S8 Norse Group          15,539,000               6
Albiorix S/2000 S11 Gallic Group          16,182,000              26
S/2007 S2 S/2007 S2          16,523,162               6
Bebhionn S/2004 S11 Inuit Group          16,898,414               6
Erriapus S/2000 S10 Gallic Group          17,342,000               9
Skoll S/2006 S8          17,473,768               6
Siarnaq S/2000 S3 Inuit Group          17,531,000              32
Tarqeq S/2007 S1          17,911,000               7
Tarvos S/2000 S4 Gallic Group          17,982,000              13
S/2004 S13 S/2004 S13 Norse Group          18,056,257               6
Greip S/2006 S4          18,065,667               6
Hyrrokkin S/2004 S19          18,168,291               8
Mundilfari S/2000 S9 Norse Group          18,418,000               7
Jarnsaxa S/2006 S6          18,556,916               6
S/2006 S1 S/2006 S1          18,930,254               6
Narvi S/2003 S1 Norse Group          19,007,000               7
S/2004 S17 S/2004 S17 Norse Group          19,099,179               4
S/2007 S3 S/2007 S3          19,179,348               5
Bergelmir S/2004 S15 Norse Group          19,372,195               6
Suttungr S/2000 S12 Norse Group          19,459,000               6
Aegir S/2004 S10 Norse Group          19,614,391               6
Hati S/2004 S14 Norse Group          19,709,344               6
S/2004 S12 S/2004 S12 Norse Group          19,905,871               5
Thrymr S/2000 S7 Norse Group          19,941,000               6
Bestla S/2004 S18 Norse Group          19,958,738               7
Farbauti S/2004 S9 Norse Group          19,984,783               5
S/2004 S7 S/2004 S7 Norse Group          20,576,697               6
S/2006 S3 S/2006 S3          21,076,295               6
Fenrir S/2004 S16 Norse Group          21,930,648               4
Surtur S/2006 S7          22,243,637               6
Kari S/2006 S2          22,321,218               7
Loge S/2006 S5          22,984,326               6
Ymir S/2000 S1 Norse Group          23,041,000              18
Fornjot S/2004 S8 Norse Group          24,484,389               6
         
         
Uranus (total moons):  27        
Uranus Equator                25,559       51,118
Ring 6                41,837    
Ring 5                42,235    
Ring 4                42,571    
Alpha ring                44,718    
Beta ring                45,661    
Eta ring                47,176    
Gamma ring                47,626    
Delta ring                48,303    
Cordelia S/1986 U7 ε Ring Shepherd                49,800              40
Lambda ring                50,024    
Epsilon ring                51,149    
Ophelia S/1986 U8 ε Ring Shepherd                53,800              43
Bianca S/1986 U9                59,200              51
Cressida S/1986 U3                61,800              80
Desdemona S/1986 U6                62,700              64
Juliet S/1986 U2                64,400              94
Portia S/1986 U1                  66,100            135
Nu ring R/2003 U2                67,700    
Rosalind S/1986 U4                69,900              72
Cupid S/2003 U2                74,800              26
Belinda S/1986 U5                75,300              81
Perdita S/1986 U10                76,420              20
Puck S/1985 U1                86,000            162
Mu ring R/2003 U1                92,700    
Mab S/2003 U1 μ Ring Source                97,734              10
Miranda V              129,900            472
Ariel I              190,900         1,158
Umbriel II              266,000         1,169
Titania III              436,300         1,578
Oberon IV              583,500         1,523
Francisco S/2001_U3 Irregular, Inner            4,276,000              12
Caliban S/1997 U1 Irregular, Retrograde, Inner            7,231,000              98
Stephano S/1999 U2 Irregular, Retrograde, Inner            8,004,000              20
Trinculo S/2001 U1 Irregular, Retrograde, Inner            8,504,000              10
Sycorax S/1997 U2 Irregular, Retrograde, Outer          12,179,000            190
Margaret S/2003_U3 Irregular          14,345,000              11
Prospero S/1999 U3 Irregular, Retrograde, Outer          16,256,000              30
Setebos S/1999 U1 Irregular, Retrograde, Outer          17,418,000              30
Ferdinand S/2001_U2 Irregular, Retrograde, Outer          20,901,000              12
         
         
Neptune (total moons): 14        
Neptune Equator                24,776       49,552
Galle ring 1989 N3R                41,900    
Naiad S/1989 N6 Regular                48,227              66
Thalassa S/1989 N5 Regular                50,075              82
Despina S/1989 N3 Regular                52,526            150
LeVerrier ring 1989 N2R                53,200    
Lassell ring                53,200    
Arago ring                57,200    
Galatea S/1989 N4 Regular                61,953            176
Liberte ("Leading" ring arc)                62,900    
Egalite ("Equidistant" ring arc)                62,900    
Fraternite ("Following" ring arc)                62,900    
Courage ring arc                62,900    
Adams ring 1989 N1R                62,933    
Larissa S/1989 N2 Regular                73,548            194
S/2004 N1 S/2004 N1              105,300              20
Proteus S/1989 N1 Regular              117,647            420
Triton I Retrograde              354,800         2,707
Nereid II Irregular            5,513,400            340
Halimede S/2002_N1 Irregular, Retrograde          15,728,000              48
Sao S/2002_N2 Irregular          22,422,000              48
Laomedeia S/2002_N3 Irregular          23,571,000              48
Psamathe S/2003_N1 Irregular, Retrograde          46,695,000              60
Neso S/2002_N4 Irregular, Retrograde          48,387,000              28
         
         
Pluto (total moons):   5        
Pluto Equator                  1,180         2,360
Charon S/1978 P1                19,571         1,186
Styx S/2012 (134340) 1                42,000              25
Nix S/2005 P2                48,675            137
Kerberos S/2011 P1                59,000              34
Hydra S/2005 P1                64,780            167
         
         
Haumea (total moons): 2 2003 EL61 'Santa'        
Haumea Equator                     650         1,300
Namaka 'Blitzen'                39,000            170
Hi'iaka 'Rudolph'                49,500            310
         
         
Makemake (total moons): 0 2005 FY9        
Makemake Equator                     715         1,430
  S/2015 1 (136472) 'MK 2'    20,000    160
             
         
Eris (total moons): 1 2003 UB313  'Xena'        
Eris Equator                  1,163         2,326
Dysnomia   'Gabrielle'                37,370            684
 
 
Planet Moons: 173
Dwarf Planet Moons: 8
Total Moons: 181



(Moons in red have not been well-tracked and may have become "lost").