Dwarf planets
The five recognised worlds
Rounded, but not in charge
The dividing line is gravitational dominance. A dwarf planet has enough gravity to pull itself into a sphere, but not enough to have swept its orbital lane clear of other objects. Ceres is the odd one out — the only dwarf planet in the inner solar system, and the largest body in the asteroid belt, holding about a third of the belt’s entire mass. The other four live out in the cold, among the icy bodies of the Kuiper Belt and beyond.
Eris is the heavyweight: slightly smaller than Pluto but around 27% more massive, and its discovery in 2005 is what triggered the debate that reclassified Pluto. Haumea is one of the strangest objects known — spinning so fast, once every four hours, that it has been stretched into an egg shape, with two moons and its own ring.
Pluto is the only dwarf planet you can currently fly to on this site: find it far beyond Neptune in the interactive view.
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Every figure on this page is a real, rounded value checked against primary sources. Found something out of date? See how we keep it accurate.