A terrestrial planet, telluric planet or rocky planet is a planet that is composed primarily of silicate rocks or metals. Within the Solar System, the terrestrial planets are the inner planets closest to the Sun. The terms are derived from Latin words for Earth (Terra and Tellus), as these planets are, in terms of composition, "Earth-like".
Terrestrial planets have a solid planetary surface, making them substantially different from the much larger gas giants, which are composed mostly of some combination of hydrogen, helium, and water existing in various physical states.
Read more about Terrestrial Planet: Structure, Solar Terrestrial Planets, Extrasolar Terrestrial Planets, Types
Famous quotes containing the word planet:
“Have you not budged an inch, then? Such is the daily news. Its facts appear to float in the atmosphere.... We should wash ourselves clean of such news. Of what consequence, though our planet explode, if there is no character involved in the explosion? In health we have not the least curiosity about such events. We do not live for idle amusement. I would not run round a corner to see the world blow up.”
—Henry David Thoreau (1817–1862)