unusual dwarf planet orbiting the Sun in the Kuiper belt beyond Pluto. It was discovered in 2003 by a team of American astronomers at Cerro Tololo Inter-American Observatory. Originally called 2003 EL61, Haumea is named for the Hawaiian goddess of birth and fertility. Haumea is an elongated object, unusual for a dwarf planet; its dimensions are 980 × 750 × 500 km (610 × 470 × 310 miles). It has a fast rotation period of 3.9 hours, which may be the reason for Haumea's elongation. Eight other Kuiper belt objects have orbits similar to Haumea's; these objects and Haumea's fast rotation may have been caused by a collision of Haumea with some object in the distant past. Unlike most objects in the Kuiper belt, Haumea is not an equal mixture of ice and rock but has a thin icy crust covering a rocky interior. (The name Haumea alludes to this structure since the goddess Haumea is also associated with stone.) In 2005 two moons of Haumea were discovered and were subsequently named after daughters of Haumea. The larger moon, Hi‘iaka, is named after the goddess of the island of Hawaii and of the hula; the smaller moon, Namaka, is named after a water spirit. In September 2008 the International Astronomical Union designated Haumea as the fifth dwarf planet and the fourth plutoid.