Terrestrial planets
- These are smallish planets made out of rock (density between 4
and 6X water).
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- They are large enough that they have melted and the dense material settled to the center leading to iron/nickel cores.
- Range in mass from 6% to 1 Earth mass.
- They have very thin atmospheres, if any, and dry.
- Earth is only about 0.2% water.
