Distances of moons of other planets

Mark Pottenger

September 2006


With the recent naming of 136199 Eris and its moon Dysnomia, I saw a question on a discussion list about astrologically separating their interpretations. This prompted me to dig out a few numbers to see how practical such an effort might be, not just for Eris and Dysnomia, but for any planets and moons in our solar system.


I suggest not making such an attempt because planets and their moons are always conjunct. Most are so closely conjunct that separate interpretations would be very difficult. Among the larger moons, the greatest possible separation is about 11 minutes of arc for Jupiter’s Callisto—the rest of the large moons are visually closer to their planets than that. The largest possible visual separation of any moon from its planet is about 3 degrees for Jupiter’s farthest-flung moons—most planet-moon separations are much smaller.


The main astrological technique that comes to mind immediately to allow separate interpretations would require a program that includes planets’ moons as separate points in lists of timed hits (progressions or transits). Then you would need a lot of well-timed events to check against the differing moments of planet and moon aspects. High-order harmonics are another possible technique.


I don’t know if any astrological software even offers positions of planetary moons, though it could exist (I don’t try to keep track of everything that is available). Accurate positions would certainly be a lot of work since orbital information for moons is in a variety of different forms.


You can easily make an estimate of how far apart a planet and moon could appear from Earth. (You can find most of the number you need in Wikipedia more conveniently than by hunting through reference books.) If your data sources give a mix of astronomical units and kilometers, convert all data to AU first. (1 AU = 149,597,870.7 km.)

Assume the moon’s orbit is angled so that its maximum planetocentric distance is perpendicular to the line of sight from Earth. (In most cases, the actual angle will reduce the maximum separation from the viewpoint of Earth, so this gives you an upper limit.)

Calculate the moon’s maximum planetocentric distance as moon’s semi-major axis times (1 + eccentricity).

Calculate the planet’s perihelion distance as planet’s semi-major axis times (1 - eccentricity).

Subtract the Earth’s aphelion distance from the planet’s perihelion distance to get the closest possible approach of the two planets. (This is another approximation of a limiting value. The two planets could only get this close if the Earth’s aphelion and the planets perihelion were aligned in space, which will rarely be the case.)

Calculate the circumference of a circle at the two-planet closest approach distance as distance * 2 * Pi.

Divide the moon’s maximum planetocentric distance by the two-planet closest approach circumference. (We are ignoring straight line vs. circle issues here as negligible in light of all the other simplifying assumptions.) This gives you the maximum angle an observer on Earth could see between the planet and the moon. Convert to degrees, minutes or seconds. Remember that this is an estimated maximum and that actual separations (which would require a LOT more calculations) will usually be less. Also remember that for some moons this separation will NOT be along the ecliptic, so the maximum separation in zodiacal longitude will be a smaller value.


Visibile separation of planets and their moons

1 AU = 149,597,870.66 km

Planet:

Axis AU

Eccentricity

Perihelion

Aphelion

EarthMin AU

Circumf AU

Mercury

0.3870989

0.2056307

0.3074995

0.4666984

0.5165915

3.2458404

Venus

0.7233320

0.0067732

0.7184327

0.7282313

0.2550586

1.6025805

Earth

1.0000001

0.0167102

0.9832899

1.0167103

n/a

n/a

Mars

1.5236623

0.0934123

1.3813335

1.6659912

0.3646231

2.2909947

Jupiter

5.2033630

0.0483927

4.9515584

5.4551676

3.9682685

24.9333666

Saturn

9.5370703

0.0541506

9.0206322

10.0535084

8.0039219

50.2901245

Uranus

19.1912639

0.0471677

18.2860560

20.0964719

17.2693456

108.5064987

Neptune

30.0689635

0.0085859

29.8107953

30.3271317

28.7940849

180.9185714

Pluto

39.4816868

0.2488077

29.6583407

49.3050329

28.6416303

179.9606709

136199 Eris

67.6681000

0.4417700

37.7743635

97.5618365

36.7576531

230.9551461


Moon:

Axis in km

Axis in AU

Eccentricity

Peri

Ap

Fract. Of Circ

AsDegrees

AsMinutes

AsSeconds

1 AU Elong

ElongSecs

Moons of Mars

I Phobos

9,377

0.0000627

0.0150

0.0000617

0.0000636

0.0000278

0.0100

0.60

36.0



II Deimos

23,460

0.0001568

0.0004

0.0001568

0.0001569

0.0000685

0.0247

1.48

88.7



Moons of Jupiter

XVI Metis

127,690

0.0008536

0.0012

0.0008525

0.0008546

0.0000343

0.0123

0.74

44.4



XV Adrastea

128,690

0.0008602

0.0018

0.0008587

0.0008618

0.0000346

0.0124

0.75

44.8



V Amalthea

181,170

0.0012110

0.0031

0.0012073

0.0012148

0.0000487

0.0175

1.05

63.1

249.55

62.9

XIV Thebe

221,700

0.0014820

0.0177

0.0014557

0.0015082

0.0000605

0.0218

1.31

78.4

305.95

77.1

I Io

421,700

0.0028189

0.0041

0.0028073

0.0028304

0.0001135

0.0409

2.45

147.1



II Europa

671,034

0.0044856

0.0094

0.0044434

0.0045277

0.0001816

0.0654

3.92

235.3



III Ganymede

1,070,412

0.0071553

0.0011

0.0071474

0.0071631

0.0002873

0.1034

6.21

372.3



IV Callisto

1,882,709

0.0125851

0.0074

0.0124920

0.0126783

0.0005085

0.1831

10.98

659.0



Themisto

7,393,200

0.0494205

0.2116

0.0389631

0.0598779

0.0024015

0.8645

51.87

3112.4



Leda

11,097,245

0.0741805

0.1854

0.0604274

0.0879336

0.0035267

1.2696

76.18

4570.7



Himalia

11,432,435

0.0764211

0.1443

0.0653935

0.0874487

0.0035073

1.2626

75.76

4545.5



Lysithia

11,653,225

0.0778970

0.1132

0.0690791

0.0867149

0.0034779

1.2520

75.12

4507.3



Elara

11,683,115

0.0780968

0.1723

0.0646407

0.0915529

0.0036719

1.3219

79.31

4758.8



Carpo

17,144,875

0.1146064

0.2736

0.0832501

0.1459627

0.0058541

2.1075

126.45

7586.9



Euporie

19,088,435

0.1275983

0.0960

0.1153489

0.1398477

0.0056089

2.0192

121.15

7269.1



Thelxinoe

20,453,755

0.1367249

0.2685

0.1000143

0.1734355

0.0069560

2.5041

150.25

9014.9



Euanthe

20,464,855

0.1367991

0.2000

0.1094393

0.1641589

0.0065839

2.3702

142.21

8532.7



Helike

20,540,265

0.1373032

0.1375

0.1184240

0.1561824

0.0062640

2.2550

135.30

8118.1



Orthosie

20,567,970

0.1374884

0.2433

0.1040375

0.1709393

0.0068558

2.4681

148.09

8885.2



Iocaste

20,722,565

0.1385218

0.2874

0.0987106

0.1783330

0.0071524

2.5749

154.49

9269.5



Ananke

20,815,225

0.1391412

0.3963

0.0839995

0.1942828

0.0077921

2.8051

168.31

10098.5



Praxidike

20,823,950

0.1391995

0.1840

0.1135868

0.1648122

0.0066101

2.3796

142.78

8566.7



Harpalyke

21,063,815

0.1408029

0.2441

0.1064329

0.1751729

0.0070256

2.5292

151.75

9105.2



Hermippe

21,182,085

0.1415935

0.2290

0.1091686

0.1740184

0.0069793

2.5126

150.75

9045.2



Thyone

21,405,570

0.1430874

0.2526

0.1069435

0.1792313

0.0071884

2.5878

155.27

9316.2



Mneme

21,427,110

0.1432314

0.2214

0.1115200

0.1749428

0.0070164

2.5259

151.55

9093.3



Aitne

22,285,160

0.1489671

0.3927

0.0904677

0.2074665

0.0083208

2.9955

179.73

10783.8



Kale

22,409,210

0.1497963

0.2011

0.1196723

0.1799204

0.0072160

2.5978

155.87

9352.0



Taygete

22,438,650

0.1499931

0.3678

0.0948256

0.2051606

0.0082284

2.9622

177.73

10663.9



Chaldene

22,713,445

0.1518300

0.2916

0.1075564

0.1961036

0.0078651

2.8314

169.89

10193.2



Erinome

22,986,265

0.1536537

0.2552

0.1144413

0.1928661

0.0077353

2.7847

167.08

10024.9



Aoede

23,044,175

0.1540408

0.6012

0.0614315

0.2466501

0.0098924

3.5613

213.68

12820.5



Kallichore

23,111,825

0.1544930

0.2042

0.1229455

0.1860405

0.0074615

2.6861

161.17

9670.1



Kalyke

23,180,775

0.1549539

0.2140

0.1217938

0.1881140

0.0075447

2.7161

162.96

9777.9



Eurydome

23,230,860

0.1552887

0.3770

0.0967449

0.2138326

0.0085762

3.0874

185.25

11114.7



Pasithee

23,307,320

0.1557998

0.3289

0.1045573

0.2070424

0.0083038

2.9894

179.36

10761.8



Cyllene

23,396,270

0.1563944

0.4116

0.0920225

0.2207663

0.0088543

3.1875

191.25

11475.1



Eukelade

23,483,695

0.1569788

0.2829

0.1125695

0.2013881

0.0080771

2.9077

174.46

10467.9



Hegemone

23,702,510

0.1584415

0.4077

0.0938449

0.2230381

0.0089454

3.2203

193.22

11593.2



Arche

23,717,050

0.1585387

0.1492

0.1348847

0.1821927

0.0073072

2.6306

157.84

9470.1



Carme

23,734,465

0.1586551

0.3122

0.1091230

0.2081872

0.0083497

3.0059

180.35

10821.3



Isonoe

23,832,630

0.1593113

0.1665

0.1327860

0.1858366

0.0074533

2.6832

160.99

9659.5



Pasiphaë

24,094,770

0.1610636

0.2953

0.1135015

0.2086257

0.0083673

3.0122

180.73

10844.1



Sinope

24,214,390

0.1618632

0.2468

0.1219154

0.2018110

0.0080940

2.9138

174.83

10489.8



Sponde

24,252,625

0.1621188

0.4432

0.0902677

0.2339698

0.0093838

3.3782

202.69

12161.4



Autonoe

24,264,445

0.1621978

0.3690

0.1023468

0.2220488

0.0089057

3.2060

192.36

11541.8



Callirrhoe

24,356,030

0.1628100

0.2644

0.1197630

0.2058570

0.0082563

2.9723

178.34

10700.1



Megaclite

24,687,240

0.1650240

0.3078

0.1142296

0.2158184

0.0086558

3.1161

186.97

11217.9



Skipped several unnamed moons.

S/2003 J 2

30,290,845

0.2024818

0.1882

0.1643747

0.2405889

0.0096493

3.4737

208.42

12505.5



Moons of Saturn

XVIII Pan

133,584

0.0008930

0.0000

0.0008929

0.0008930

0.0000178

0.0064

0.38

23.0



XXXV Daphnis

136,505

0.0009125

0.0000

0.0009125

0.0009125

0.0000181

0.0065

0.39

23.5



XV Atlas

137,670

0.0009203

0.0012

0.0009192

0.0009214

0.0000183

0.0066

0.40

23.7



XVII Prometheus

139,380

0.0009317

0.0022

0.0009296

0.0009337

0.0000186

0.0067

0.40

24.1



XVII Pandora

141,720

0.0009473

0.0042

0.0009434

0.0009513

0.0000189

0.0068

0.41

24.5



XI Epimetheus

151,422

0.0010122

0.0098

0.0010023

0.0010221

0.0000203

0.0073

0.44

26.3



X Janus

151,472

0.0010125

0.0068

0.0010056

0.0010194

0.0000203

0.0073

0.44

26.3



I Mimas

185,404

0.0012393

0.0202

0.0012143

0.0012644

0.0000251

0.0091

0.54

32.6



XXXII Methone

194,440

0.0012998

0.0001

0.0012996

0.0012999

0.0000258

0.0093

0.56

33.5



XXXIII Pallene

212,280

0.0014190

0.0040

0.0014133

0.0014247

0.0000283

0.0102

0.61

36.7



II Enceladus

237,950

0.0015906

0.0047

0.0015831

0.0015981

0.0000318

0.0114

0.69

41.2



III Tethys

294,619

0.0019694

0.0000

0.0019694

0.0019694

0.0000392

0.0141

0.85

50.8



XIII Telesto

294,619

0.0019694

0.0000

0.0019694

0.0019694

0.0000392

0.0141

0.85

50.8



XIV Calypso

294,619

0.0019694

0.0000

0.0019694

0.0019694

0.0000392

0.0141

0.85

50.8



IV Dione

377,396

0.0025227

0.0022

0.0025172

0.0025283

0.0000503

0.0181

1.09

65.2



XII Helene

377,396

0.0025227

0.0022

0.0025172

0.0025283

0.0000503

0.0181

1.09

65.2



XXXIV Polydeuces

377,396

0.0025227

0.0192

0.0024743

0.0025712

0.0000511

0.0184

1.10

66.3



V Rhea

527,108

0.0035235

0.0013

0.0035191

0.0035279

0.0000702

0.0253

1.52

90.9



VI Titan

1,221,931

0.0081681

0.0289

0.0079322

0.0084040

0.0001671

0.0602

3.61

216.6



VII Hyperion

1,481,010

0.0098999

0.1230

0.0086822

0.0111177

0.0002211

0.0796

4.78

286.5



VIII Iapetus

3,560,820

0.0238026

0.0286

0.0231216

0.0244837

0.0004868

0.1753

10.52

631.0



XXIV Kiviuq

11,333,200

0.0757578

0.1560

0.0639396

0.0875760

0.0017414

0.6269

37.61

2256.9



XXII Ijiraq

11,372,000

0.0760171

0.3430

0.0499433

0.1020910

0.0020300

0.7308

43.85

2630.9



XI Pheobe

12,955,759

0.0866039

0.1562

0.0730728

0.1001350

0.0019911

0.7168

43.01

2580.5



XX Paaliaq

14,923,800

0.0997594

0.4330

0.0565636

0.1429553

0.0028426

1.0233

61.40

3684.0



XXVII Skathi

15,576,200

0.1041205

0.2460

0.0785068

0.1297341

0.0025797

0.9287

55.72

3343.3



XXVI Albiorix

16,401,600

0.1096379

0.5210

0.0525166

0.1667593

0.0033159

1.1937

71.62

4297.5



XXVIII Erriapo

17,408,700

0.1163700

0.5340

0.0542284

0.1785115

0.0035496

1.2779

76.67

4600.3



XXIX Siarnaq

17,905,700

0.1196922

0.4790

0.0623596

0.1770248

0.0035201

1.2672

76.03

4562.0



XXI Tarvos

18,160,200

0.1213934

0.5470

0.0549912

0.1877957

0.0037342

1.3443

80.66

4839.6



XXV Mundilfari

18,360,100

0.1227297

0.1980

0.0984292

0.1470302

0.0029236

1.0525

63.15

3789.0



XXXI Narvi

19,370,700

0.1294851

0.3200

0.0880499

0.1709204

0.0033987

1.2235

73.41

4404.7



XXIII Suttungr

19,666,700

0.1314638

0.1310

0.1142420

0.1486855

0.0029566

1.0644

63.86

3831.7



XXX Thrymr

20,810,300

0.1391083

0.4530

0.0760922

0.2021243

0.0040192

1.4469

86.81

5208.8



XIX Ymir

23,174,600

0.1549126

0.3580

0.0994539

0.2103714

0.0041832

1.5059

90.36

5421.4



Skipped several unnamed moons.

S/2004 S 8

23,608,900

0.1578157

0.1860

0.1284620

0.1871695

0.0037218

1.3398

80.39

4823.4



Moons of Uranus

VI Cordelia

49,752

0.0003326

0.0005

0.0003324

0.0003327

0.0000031

0.0011

0.07

4.0



VII Ophelia

53,764

0.0003594

0.0101

0.0003558

0.0003630

0.0000033

0.0012

0.07

4.3



VIII Bianca

59,165

0.0003955

0.0009

0.0003951

0.0003958

0.0000036

0.0013

0.08

4.7



IX Cressida

61,767

0.0004129

0.0002

0.0004128

0.0004130

0.0000038

0.0014

0.08

4.9



X Desdemona

62,659

0.0004188

0.0002

0.0004188

0.0004189

0.0000039

0.0014

0.08

5.0



XI Juliet

64,358

0.0004302

0.0006

0.0004300

0.0004305

0.0000040

0.0014

0.09

5.1



XII Portia

66,097

0.0004418

0.0001

0.0004418

0.0004419

0.0000041

0.0015

0.09

5.3



XIII Rosalind

69,927

0.0004674

0.0001

0.0004674

0.0004675

0.0000043

0.0016

0.09

5.6



XXVII Cupid

74,392

0.0004973

0.0013

0.0004966

0.0004979

0.0000046

0.0017

0.10

5.9



XIV Belinda

75,255

0.0005030

0.0001

0.0005030

0.0005031

0.0000046

0.0017

0.10

6.0



XXV Perdita

76,416

0.0005108

0.0030

0.0005093

0.0005123

0.0000047

0.0017

0.10

6.1



XV Puck

86,004

0.0005749

0.0001

0.0005749

0.0005749

0.0000053

0.0019

0.11

6.9



XXVI Mab

97,736

0.0006533

0.0025

0.0006517

0.0006550

0.0000060

0.0022

0.13

7.8



V Miranda

129,390

0.0008649

0.0013

0.0008638

0.0008660

0.0000080

0.0029

0.17

10.3



I Ariel

191,020

0.0012769

0.0012

0.0012754

0.0012784

0.0000118

0.0042

0.25

15.3



II Umbriel

266,000

0.0017781

0.0039

0.0017712

0.0017850

0.0000165

0.0059

0.36

21.3



III Titania

435,910

0.0029139

0.0011

0.0029107

0.0029171

0.0000269

0.0097

0.58

34.8



IV Oberon

583,520

0.0039006

0.0014

0.0038951

0.0039061

0.0000360

0.0130

0.78

46.7



XXII Francisco

4,276,000

0.0285833

0.1459

0.0244130

0.0327536

0.0003019

0.1087

6.52

391.2



XVI Caliban

7,231,000

0.0483362

0.1588

0.0406605

0.0560120

0.0005162

0.1858

11.15

669.0



XX Stephano

8,004,000

0.0535034

0.2295

0.0412244

0.0657825

0.0006063

0.2183

13.10

785.7



XXI Trinculo

8,578,000

0.0573404

0.2079

0.0454193

0.0692615

0.0006383

0.2298

13.79

827.3



XVII Sycorax

12,179,000

0.0814116

0.5224

0.0388822

0.1239410

0.0011422

0.4112

24.67

1480.3



XXIII Margaret

14,345,000

0.0958904

0.6608

0.0325260

0.1592548

0.0014677

0.5284

31.70

1902.1



XVIII Prospero

16,243,000

0.1085777

0.4431

0.0604669

0.1566885

0.0014440

0.5199

31.19

1871.5



XIX Setebos

17,501,000

0.1169870

0.5843

0.0486315

0.1853424

0.0017081

0.6149

36.90

2213.7



XXIV Ferdinand

20,901,000

0.1397146

0.3682

0.0882717

0.1911575

0.0017617

0.6342

38.05

2283.2



Moons of Neptune

III Naiad

48,227

0.0003224

0.0004

0.0003222

0.0003225

0.0000018

0.0006

0.04

2.3



IV Thalassa

50,075

0.0003347

0.0002

0.0003347

0.0003348

0.0000019

0.0007

0.04

2.4



V Despina

52,526

0.0003511

0.0002

0.0003510

0.0003512

0.0000019

0.0007

0.04

2.5



VI Galatea

61,953

0.0004141

0.0000

0.0004141

0.0004141

0.0000023

0.0008

0.05

3.0



VII Larissa

73,548

0.0004916

0.0014

0.0004910

0.0004923

0.0000027

0.0010

0.06

3.5



VIII Proteus

117,647

0.0007864

0.0005

0.0007860

0.0007868

0.0000043

0.0016

0.09

5.6



I Triton

354,800

0.0023717

0.0000

0.0023717

0.0023717

0.0000131

0.0047

0.28

17.0

488.49

17.0

II Nereid

5,513,400

0.0368548

0.7512

0.0091695

0.0645401

0.0003567

0.1284

7.71

462.3



S/2002 N 1

15,728,000

0.1051352

0.5711

0.0450925

0.1651779

0.0009130

0.3287

19.72

1183.2



S/2002 N 2

22,422,000

0.1498818

0.2931

0.1059515

0.1938122

0.0010713

0.3857

23.14

1388.4



S/2002 N 3

23,571,000

0.1575624

0.4237

0.0908032

0.2243216

0.0012399

0.4464

26.78

1606.9



X Psamathe

46,695,000

0.3121368

0.4499

0.1717065

0.4525671

0.0025015

0.9005

54.03

3241.9



S/2002 N 4

48,387,000

0.3234471

0.4945

0.1635025

0.4833917

0.0026719

0.9619

57.71

3462.7



Moons of Pluto

I Charon

19,571

0.0001308

0.0000

0.0001308

0.0001308

0.0000007

0.0003

0.02

0.9

0

0.000004

II Nix

48,675

0.0003254

0.0020

0.0003247

0.0003260

0.0000018

0.0007

0.04

2.3



III Hydra

64,780

0.0004330

0.0050

0.0004309

0.0004352

0.0000024

0.0009

0.05

3.1



Moons of Eris

Dysnomia

36,000

0.0002406

0.0000

0.0002406

0.0002406

0.0000010

0.0004

0.02

1.4




Most of the columns in the above table should be self-explanatory. AsDegrees, AsMinutes and AsSeconds are the answers to look at (mostly AsSeconds). “1 AU Elong” is a value I found in the Explanatory Supplement for a few moons and “ElongSecs” is that value converted to seconds of arc at the planet’s minimum distance from Earth. I included it as a cross-check of the calculations described (with all their simplifying assumptions).


For anyone who wants to plug in other values, here are two sample lines showing the calculations in the spreadsheet:

Mars 1.52366231 0.09341233 =B6*(1-C6) =B6*(1+C6) =D6-E5 =F6*2*3.14159265358979

I Phobos 9377 =B16/G1 0.015 =C16*(1-D16) =C16*(1+D16) =F16/G6 =G16*360 =H16*60 =I16*60


As you can see from the tables, the maximum possible separation between 136199 Eris and Dysnomia is only 1.4 seconds of arc. Given the angles and the current uncertainty of the Dysnomia data, the actual ecliptic separation is almost certainly less. This is EXTREMELY close for any astrological work. It is more than the mean error in tests of my Eris ephemeris against observations but less than my maximum error, so even if the orbital elements needed to calculate Dysnomia were available I would be VERY skeptical of any positions I could produce.


Pluto and Charon are a special case—really a double planet. The barycenter of the Pluto-Charon orbit is NOT below the surface of Pluto the way the Earth-Moon barycenter is below the surface of the Earth. If I read one value right in an astronomical reference book, the maximum visual separation of Pluto and Charon can’t exceed 0.000004 seconds of arc, so the point called Pluto in charts is really Pluto-Charon.


For practical purposes, if one is going to think about planetary moons at all, one should think of the astrological interpretation of the planet as actually interpreting the planet plus its moons. Thus, what astrologers really work with is:

Mars + Phobos + Deimos

Jupiter + Metis + Adrastea + Amalthea + Thebe + Io + Europa + Ganymede + Callisto + Themisto + Leda + Himalia + Lysithia + Elara + Carpo + Euporie + Thelxinoe + Euanthe + Helike + Orthosie + Iocaste + Ananke + Praxidike + Harpalyke + Hermippe + Thyone + Mneme + Aitne + Kale + Taygete + Chaldene + Erinome + Aoede + Kallichore + Kalyke + Eurydome + Pasithee + Cyllene + Eukelade + Hegemone + Arche + Carme + Isonoe + Pasiphaë + Sinope + Sponde + Autonoe + Callirrhoe + Megaclite + moons yet to be named

Saturn + Pan + Daphnis + Atlas + Prometheus + Pandora + Epimetheus + Janus + Mimas + Methone + Pallene + Enceladus + Tethys + Telesto + Calypso + Dione + Helene + Polydeuces + Rhea + Titan + Hyperion + Iapetus + Kiviuq + Ijiraq + Pheobe + Paaliaq + Skathi + Albiorix + Erriapo + Siarnaq + Tarvos + Mundilfari + Narvi + Suttungr + Thrymr + Ymir + moons yet to be named

Uranus + Cordelia + Ophelia + Bianca + Cressida + Desdemona + Juliet + Portia + Rosalind + Cupid + Belinda + Perdita + Puck + Mab + Miranda + Ariel + Umbriel + Titania + Oberon + Francisco + Caliban + Stephano + Trinculo + Sycorax + Margaret + Prospero + Setebos + Ferdinand

Neptune + Naiad + Thalassa + Despina + Galatea + Larissa + Proteus + Triton + Nereid + Psamathe + moons yet to be named

Pluto + Charon + Nix + Hydra

Eris + Dysnomia


2019 note: more moons have been discovered and/or named since I wrote this, but I won't expand the 2006 list, since the basic point won't be changed by more examples.


Copyright © 2006 Mark Pottenger


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