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
Wonders of the Solar System greenhouse planet Venus, a planet often referred to as "Earth's twin", and compares it to the vulcan geology of the Deccan Plateau. An example of Earth's interconnectivity with the solar system reveals that Jupiter's gravitational effect could potentially send an asteroid through the Asteroid Belt on a collision course with Earth, as evidenced by Meteor Crater. The same gravitational force is also shown to give the Jovian moon Io geological life (given the absence of meteor impact evidence there) as paralleled by the volcanism of Erta Ale in Ethiopia. All in all, with the universal laws of physics at play