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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