7. Inner Planets They all have rocky surfaces, and they are warmer than the outer planets.
8. Earth is different from the other inner planets. It has a watery surface. It is the only planet with a lot of oxygen in its atmosphere. Earth has plant life and animal life.
11. Outer Planets are made mostly of frozen gases. Their surfaces are colder than the inner planets because they are farther away from the sun. Most outer planets have many moons.
12. Pluto is different from other outer planets. It is the smallest planet in the solar system.