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
The Impossible Planet The Impossible Planet "The Impossible Planet" is the eighth episode of the second series of the British science fiction television series "Doctor Who", which was first broadcast on BBC One on 3 June 2006. It is the first part of a two-part story. The second part, "The Satan Pit", was broadcast on 10 June. The episode is set on Krop Tor, a planet orbiting a black hole. In the episode, a human expedition group drilling on the planet is terrorised by a creature calling itself the Beast (Gabriel Woolf), which possesses the Ood slaves in the humans' base. The TARDIS