Terrestrial planet Terrestrial planet 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, i.e. Mercury, Venus, Earth, and Mars. The terms "terrestrial planet" and "telluric planet" are derived from Latin words for Earth ("Terra" and "Tellus"), as these planets are, in terms of structure, "Earth-like". Terrestrial planets have a solid planetary surface, making them substantially different from the larger giant planets, which are composed mostly of some combination of hydrogen, helium, and water existing in various
Terminus (planet) Terminus (planet) Terminus is a fictional planet at the edge of the Galaxy in Isaac Asimov's "Foundation Series", home of the Foundation (later capital of the Foundation Federation). Terminus is the sole planet orbiting an isolated star. Its nearest inhabited neighbor is Anacreon, 8 parsecs (26 light years) away, and it lies approximately 10,000 parsecs from the capital of the First Galactic Empire, Trantor, near the galactic center. There are almost no visible stars in its sky, only the huge lens of the Milky Way Galaxy. The nearby stars of the Province of Anacreon are known as "The Diamonds", with