Portal:Systems science/Article/1
The Solar System consists of the Sun and the other celestial objects gravitationally bound to it: the eight planets, their 165 known moons, three dwarf planets (Ceres, Eris, and Pluto) and their four known moons, and billions of small bodies. This last category includes asteroids, Kuiper belt objects, comets, meteoroids, and interplanetary dust.
In broad terms, the charted regions of the Solar System consist of the Sun, four terrestrial inner planets, an asteroid belt composed of small rocky bodies, four gas giant outer planets, and a second belt, called the Kuiper belt, composed of icy objects. Beyond the Kuiper belt lies the scattered disc, the heliopause, and ultimately the hypothetical Oort cloud.