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Solar system data

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
Pluto 247.7y 29.6 49.3 17.2

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, <30
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 <1,200

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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