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The Comparative Size of
The Planets


Earth and The Larger Planets

The name 'planets' is derived from the Greek meaning 'wanderers' and was originally applied to the the seven bright bodies that could easily be seen to change their positions in the sky.

Two of these were not planets at all but our Sun and our moon.

  • Planets are generally divided into two groups;
    Mercury, Venus, Earth and Mars are comparable in size and are known as 'terrestrial' planets.

  • Jupiter, Saturn, Neptune and Uranus, all much larger in size, though having a lower density, are known as the 'major' planets.

Pluto should, by virtue of of its position in the system, be a 'major' planet and by its size, a 'terrestrial' planet.

Because it does not obey Bode's Law, Pluto remains outside of these norms.

Pluto has been declared to not be a planet because its orbit often enters that of Neptune and the scientists claim that only the largest body within an orbit can be a planet.


Distance
from Sun
(million km)
Diameter
at equator
(km)
Gravity
(Earth = 1)
Mercury
58
4 991
0.27
Venus
108
12 397
0.86
Earth
150
12 761
1
Mars
228
6 762
0.37
Jupiter
778
142 807
2.64
Saturn
1 427
120 900
1.17
Uranus
2 870
47 173
0.92
Neptune
4 503
44 597
1.44
Pluto
5 909
5 796
?

Note: As of 2006 the world's scientific community
has rejected Pluto as a planet

Earth and The Smaller Planets


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