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
Ego the Living Planet the Fantastic Four as they were off planet at the time, fighting Ego. The superpowered quartet attempted to defeat Ego by removing the power cell from one of the attached, propulsion engines, which the Thing attempts to throw into Ego's "brain". In response, an angered Ego attempts to counter with his remaining engines but, with one engine now deactivated, the other propels the now-out-of-control planet into the Sun, its gravitational pull breaking apart Ego's substance. Ego, however, slowly reforms from a few surviving particles and repairs the propulsion unit. Ego then digests a number of Dire Wraiths to replenish its