The Solar System contains 1 star, 8 planets, and 63 major moons. It is divided into inner and outer planets, with the inner planets being smaller, rocky, and closer to the Sun, and the outer planets being larger, gaseous, and further from the Sun. In addition to planets and moons, the Solar System contains asteroids, comets, and meteoroids. Comets are dirty snowballs composed of dust, rock and frozen gases like methane and ammonia that reflect light from the Sun as they orbit.