Handy tables of orbits, mass, rotation periods and tilts for the planets and their moons in the Solar System.

The orbits of the planets

Name

Sidereal Period

Perihelion (AU)

Aphelion (AU)

Inclination (degrees)

Mercury

87.97d

0.31

0.47

7.0

Venus

224.70d

0.72

0.73

3.4

Earth

365.26d

0.98

1.02

0.0

Mars

686.98d

1.38

1.67

1.8

Jupiter

11.86y

4.95

5.45

1.3

Saturn

29.46y

9.01

10.07

2.5

Uranus

84.01y

18.28

20.09

0.8

Neptune

164.79y

29.80

30.32

1.8

The Sidereal Period is the time taken by the planet to return to the same place in its orbit, relative to the stars.

Perihelion and Aphelion are the planet's closest and furthest distances from the Sun, measured in Astronomical Units (AU). 1 AU is defined by the average distance from the Earth to the Sun.

The globes of the planets

Name

Equatorial Diameter (km)

Oblateness

Mass (Earth=1)

Rotation Period

Tilt (degrees)

Mercury

4878

0.0

0.06

58.65d

7

Venus

12,100

0.0

0.82

243d

177

Earth

12,756

0.0034

1.00

23.934h

23

Mars

6794

0.005

0.11

24.623h

25

Jupiter

142,800

0.065

317.89

9.842h

3

Saturn

120,000

0.108

95.17

10.233h

27

Uranus

52,400

0.03

14.56

16-28h

98

Neptune

48,400

0.02

17.24

18-20h

30

Pluto

2445

0.0

0.002

6.39d

118?

Oblateness is a measure of how the planet's figure departs from a sphere.

The Rotation Period for each planet is the period relative to the stars. This is slightly different from the period relative to the Sun, which for the Earth we call the day.

For two of the planets, Venus and Uranus, the inclination of the rotation axis is large and the planets (and Uranus's satellites) rotate in the reverse sense to that of their orbits. Otherwise, all the planets, their satellites (and the Sun) rotate and move around the Sun with the same sense of rotation.

Satellites

Planet

 

Satellite

Mean Distance (103 km)

Mean Period (days)

Diameter (km)

Earth

 

Moon

384

27.322

3,476

Mars

I

Phobos

9.38

0.319

28, 22, 18

 

II

Deimos

23.46

1.262

16, 12, 10

Jupiter

XVI

Metis

127.96

0.295

40

 

XV

Adrastea

128.98

0.298

24, 20, 16

 

V

Amalthea

181.3

0.498

270, 170, 150

 

XIV

Thebe

221.9

0.675

110,90

 

I

Io

421.6

1.769

3,652

 

II

Europa

670.9

3.551

3,138

 

III

Ganymede

1,070

7.155

5,262

 

IV

Callisto

1,880

16.689

4,800

 

XIII

Leda

11,094

238.7

10

 

VI

Himalia

11,480

250.6

180

 

X

Lysithia

11,720

259.2

20

 

VII

Elara

11,737

259.7

80

 

XII

Ananke

21,200

631

20

 

XI

Carme

22,600

692

30

 

VIII

Pasiphae

23,500

735

40

 

IX

Sinope

23,700

758

30

Saturn

XV

Atlas

137.67

0.602

38, 26

 

XVI

Prometheus

139.35

0.613

140, 100, 74

 

XVII

Pandora

141.70

0.629

110, 84, 66

 

X

Janus

151.47

0.695

220, 190, 160

 

XI

Epimetheus

151.42

0.694

140, 114, 100

 

I

Mimus

185.54

0.942

392

 

II

Enceladus

238.04

1.370

500

 

III

Tethys

294.67

1.888

1,060

 

XIII

Telesto

294.67

1.888

24, 22

 

XIV

Calypso

294.67

1.888

30, 24, 16

 

IV

Dione

377.42

2.737

1,120

 

XII

Helene

377.42

2.737

36,

 

V

Rhea

527.04

4.518

1,530

 

VI

Titan

1,221.86

15.495

5,150

 

VII

Hyperion

1,481.1

21.277

350, 234, 200

 

VIII

Iapetus

3561.3

79.331

1,460

 

IX

Pheobe

12,954

550.4

220

Uranus

VI

Cordelia

49.8

0.335

15

 

VII

Ophelia

53.8

0.376

20

 

VIII

Bianca

59.1

0.433

50

 

IX

Cressida

61.75

0.463

70

 

X

Desdemona

62.7

0.475

50

 

XI

Juliet

64.35

0.493

70

 

XII

Portia

66.09

0.513

90

 

XIII

Rosalind

69.92

0.558

50

 

XIV

Belinda

75.3

0.622

50

 

XV

Puck

86.01

0.762

170

 

V

Miranda

129.4

1.414

480

 

I

Ariel

191.0

2.520

1,170

 

II

Umbriel

266.3

4.144

1,190

 

III

Titania

435.9

8.706

1,560

 

IV

Oberon

583.5

13.463

1,550

Neptune

III

Naiad

48.2

0.30

50

 

IV

Thalassa

50.0

0.31

90

 

V

Despina

52.5

0.33

140

 

VI

Galatea

62.0

0.43

160

 

VII

Larissa

73.6

0.55

200

 

VIII

Proteus

117.6

1.12

420

 

I

Triton

354.8

5.877

3,500

 

II

Nereid

5,510

360.21

400

Pluto

I

Charon

19.7

6.387

 

Notes

  • Apart from the following the orbital planes of all satellites are within 5 degrees of that of their primary.
  • The Moon is between 18-28 degrees.
  • Jupiter XIII,VI,X and VII are at about 28 degrees. XII, XI, VIII and IX are at about 150 degrees.
  • Saturn VIII is at 15 degrees and IX is at 175.
  • Uranus I is at 159 degrees and II is at 28.
  • Pluto I is at 99 degrees.
  • The Rings of Saturn have diameters from 134000km to 480000km. The rings about the other planets are not visible from Earth.
  • Where several values are given for the diameter, this indicates that the satellite is markedly non-spherical. The numbers represent diameters along perpendicular axes.

The periods given are sidereal periods of rotation about the planet. The mean distances are given in thousands of kilometres.

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