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
3rd Rock from the Sun how he was abducted by the "3rd Rock" producers and forced to work on their production. A Post-it note is attached to the foreword, apparently written by Dick Solomon, stating he does not know why the foreword is there, but that Lithgow is an Earth actor who appeared in "some helicopter movie". 3rd Rock from the Sun 3rd Rock from the Sun is an American sitcom that aired from 1996 to 2001 on NBC. The show is about four extraterrestrials who are on an expedition to Earth, which they consider to be a very insignificant planet. The extraterrestrials pose as