This is because Haumea spins very quickly on its axis. A day on the small world would only be 4 hours long. Because of its rapid rotation, the world is flattened into a somewhat egg-like shape known as an ellipsoid. ... This allowed the team to confirm Haumea's spheroidal shape.

How did Haumea get its shape?

Billions of years ago, a large object may have collided with the body, knocking most of the surface ice away and imparting a rapid spin to Haumea. The spin, in turn, elongated Haumea into its unusual shape. The moons of Haumea may have once been part of its surface, forming much like Earth's moon did after a collision.

Why does Haumea have a unique shape?

Originally designated 2003 EL61 (and nicknamed Santa by one discovery team), Haumea is located in the Kuiper Belt, a donut-shaped region of icy bodies beyond the orbit of Neptune. ... The fast spin distorts Haumea's shape, making this dwarf planet look like a football.