Why are the inner planets rocky planets?
1 Answer
Aug 4, 2017
The inner planets are rocky because they are closer to the sun.
Explanation:
The planets formed from a protoplanetary disk of material orbiting around the sun. Planets for by material clumping together until there is a single body plus any moons in the orbit.
In the region where the inner planets formed all lighter and volatile compounds were gases. These gases also got blown further out by the solar wind.
The only materials which could clump together nearer the sun were the materials which went to make the rocky inner planets.
The volatiles could solidify further from the sun and went to make the gas and ice giant outer planets.
