Planet Properties
The best method of illustrating the differences between the planets is with the use of tables, so the differences and similarities stand out. Some basic information about the planets would make a good start so that you can compare their various attributes (such as distance from the Sun, equatorial diameter, etc.). The tables below display this information. (Illingworth, 1994; and other sources.)
| Planet | Siderial Period |
Perihelion (AU) |
Aphelion (AU) |
Inclination (degrees) |
Axial Tilt (deg) |
Axial Period (d, h, m) |
|---|---|---|---|---|---|---|
| Mercury | 87.97 d | 0.31 | 0.47 | 7.0 | 0.0 | 58, 15, 30.5 |
| Venus | 224.70 d | 0.72 | 0.73 | 3.4 | 177.3 | 243, 0, 14.4, R |
| Earth | 365.26 d | 0.98 | 1.02 | 0.0 | 23.45 | 0, 23, 56.1 |
| Mars | 686.98 d | 1.38 | 1.67 | 1.9 | 25.19 | 1, 0, 37.4 |
| Jupiter | 11.86 y | 4.95 | 5.46 | 1.3 | 3.12 | 0, 9, 55.5 |
| Saturn | 29.46 y | 9.01 | 10.04 | 2.5 | 26.73 | 0, 10, 39.4 |
| Uranus | 84.01 y | 18.31 | 20.07 | 0.8 | 97.86 | 0, 15, 36.0, R |
| Neptune | 164.79 y | 29.76 | 30.36 | 1.8 | 29.56 | 0, 18, 25.9 |
| Pluto | 248.59 y | 29.73 | 49.33 | 17.1 | 118 | 6, 9, 16.8, R |
| Planet | Equatorial Diameter (km) |
Oblateness | Mass (Earth = 1) |
Density (water = 1) |
Albedo (geom.) |
No. of Satellites |
| Mercury | 4, 878 | 0.000 | 0.06 | 5.4 | 0.11 | 0 |
| Venus | 12, 104 | 0.000 | 0.82 | 5.2 | 0.65 | 0 |
| Earth | 12, 756 | 0.003 | 1.00 | 5.5 | 0.37 | 1 |
| Mars | 6, 795 | 0.005 | 0.11 | 3.9 | 0.15 | 2 |
| Jupiter | 142, 985 | 0.065 | 317.83 | 1.3 | 0.52 | 16 + R |
| Saturn | 120, 537 | 0.108 | 95.16 | 0.7 | 0.47 | 18 + R |
| Uranus | 51, 119 | 0.030 | 14.50 | 1.3 | 0.51 | 17 + R |
| Neptune | 50, 538 | 0.026 | 17.20 | 1.8 | 0.41 | 8 + R |
| Pluto | 2, 320 | 0.000 | 0.003 | 1.1 | 0.3 | 1 |