Terrestrial Planets

Rocky planets: Mercury, Venus, Earth, and Mars. These planets have physical characteristics, chemical composition and internal structure similar to the Earth. The terrestrial planets have 0.4% of the total mass of all the planets in the Solar System. Some large satellites of planets are also similar to the characteristics of the terrestrial planets, and may be considered to be members of this group that are in orbit about a larger planet (e.g., Moon, Io).