Dwarf planets, artwork. A dwarf planet is a planetary-mass object orbiting the Sun, but not a true planet or a satellite. They are massive enough for their self- gravities to crush them into sphere but they have not cleared the neighborhood of other material around their orbits. Cerss, for example, orbits in the asteroid belt, its orbit shared with those of the 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. This illustration shows the five currently confirmed dwarf planets in the Solar System – as of 2018. From left to right they are Pluto, Eris, Makemake, Ceres and Haumea. Haumea has an ellipsoidal shape rather than a sphere, owing to its rapid spin. The Earth is shown as far left to add a sense of scale. |