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 Magic School Bus Lost in the Solar System the book. Most notably, in the episode, Janet's bragging about herself does not appear to be empty bragging and she constantly raves about how "proof" is needed for all extraordinary claims, prompting her to force Arnold to collect "proof" from every planet in the solar system, so she can prove to the students in her class that she actually traveled to all the planets. Also in this one Arnold surprisingly suggests going to outer space himself to prove to Janet the truth. Also, instead of remaining in the asteroid belt, Ms. Frizzle uses her jet pack to fly off to