Haumea

Haumea is a dwarf planet. It is about 1,560 km across – smaller than our Moon. Haumea spins once in just under 4 hours – faster than any other known body of its size. This has stretched it into an egg shape (about 2,000 x 1,500 x 1,000 km).

▶ View Haumea in the 3D model

Fact file

Type: Dwarf planet
Diameter: 1,560 km
Distance from the Sun: 6,452,000,000 km
Orbital period: 284.1 years
Temperature: -241 °C on average
Mass: 0.00067 Earth masses
Gravity: 0.04 times as strong as on Earth
Escape velocity: 0.9 km/s
Length of day: Only 3.9 hours – one of the fastest spinners in the Solar System
Number of moons: 2

Interesting facts about Haumea

Haumea spins once in just under 4 hours – faster than any other known body of its size. This has stretched it into an egg shape (about 2,000 x 1,500 x 1,000 km).
Haumea has a ring (discovered in 2017 during a stellar occultation) and two moons, Hiʻiaka and Namaka.
It is named after the Hawaiian goddess of fertility.

Frequently asked questions about Haumea

How big is Haumea?

Haumea has a diameter of 1,560 km. That is about 12% of the diameter of Earth.

How far is Haumea from the Sun?

Haumea is on average 6.45 billion km from the Sun. That is 43.13 astronomical units (AU). Sunlight takes about 6 hours to cover this distance.

How long is a year on Haumea?

Haumea takes 284.1 Earth years to travel once around the Sun.

How cold or warm is it on Haumea?

On Haumea the average temperature is −241 °C.

Name and discovery

After the Hawaiian goddess of fertility and childbirth.

Found in 2004/2005 – a team in the USA and one in Spain both claimed the discovery, a dispute that still echoes today.

Formation

Haumea was probably created by a huge collision in the early Kuiper Belt, which set it spinning rapidly and knocked off chunks of ice – these now form a “Haumea family” with similar orbits.

Atmosphere

No atmosphere; the surface is mostly almost pure water ice.

Exploration

So far observed only from Earth (including the 2017 stellar occultation, which revealed its shape, ring and brightness); no spacecraft is on its way.

Compared with Earth

Haumea is much smaller than our Moon, but extremely far away: from there the Sun would be just a bright star.

Moons of Haumea

NamakaNamaka is the smaller and inner of Haumea's two moons.HiʻiakaHiʻiaka is the larger and outer moon of Haumea, around 320 km across.

Test your knowledge of Haumea

Which dwarf planet is shaped like a rugby ball because it spins so fast?

Haumea. Haumea turns once on its axis in only about four hours – that stretches it into an ellipsoid.

The full quiz with points and badges is in the 3D model under “Explore”.

← Pluto Makemake →