Here's why:
* Gas giants are large planets composed primarily of hydrogen and helium (like Jupiter, Saturn, Uranus, and Neptune).
* Terrestrial planets are smaller and rockier, with solid surfaces (like Mercury, Venus, Earth, and Mars).
Pluto is classified as a dwarf planet. It's smaller than the terrestrial planets and lacks the gravitational dominance required to clear its orbital path of other objects, a defining characteristic of a planet.
