A terrestial planet is a planet in the inner solar system
(Mercury, Venus, Earth and Mars are terrestial planets). These
planets are mostly made of rocks.
Mercury is a terrestial planet, therefore it is made of
There are four planets that are made out of gas: Jupiter,
Saturn, Urans and Neptune.
These planets are called the "gas giants" . The other four
planets (Earth, Mercury, Venus and Mars) are mostly made out of