Exploratour - Evolution of the Solar System
The Earth and Mars are examples of two planets which are next to each other in space. One might think that because they are neighbors that they would have a similar history, but this is not so. Early in its history Earth did separate into layers. Earth has a well-shaped core and a strong magnetosphere. The interior of Mars seems only to be partially separated into layers. Mars has a small core, a weak magnetic field. A lot of its iron seems to have remained on the surface and in the rocks of the surface. This helps give the planet a reddish-borwn look which is why we call it the "Red Planet". This means that these two planets had a different history.
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