Dwarf planets and moons, illustration. A dwarf planet is a planetary mass object orbiting the Sun that is not a true planet. They are massive enough for their self-gravities to crush them into spheres, but they have not cleared the neighborhood of other material around their orbits. Ceres, for example, shares its orbit with other asteroids. All the other dwarf planets so far known are found beyond Neptune, in a region of the Solar System full of debris called the Kuiper belt. Here are the five currently confirmed dwarf planets in the Solar System – as of 2018 – along with their known natural satellites, or moons. From left to right they are Pluto (with Charon, Hydra, Mix, Kerberos and Styx), Eris (with Dysnomia), Makemake, Ceres, and finally the oddly shaped Haumea (with Hiʻiaka and Namaka). Haumea is an ellipsoidal shape rather than a sphere, owing to its rapid spin. |