Haumea was discovered in 2003. It is a dwarf planet almost the same size as Pluto, yet weighs only a third as much.
Mass: 4.2 x 1021 kg
Orbit: between 3,000,000,000 – 5,000,000,000 km from the Sun
Haumea was first identified by astronomers at the Sierra Nevada Observatory in Spain. Photographs illustrating the existence of Haumea were taken in March 2003 by a team that was led by José Luis Ortiz Moreno. However, it wasn’t until 2005 that the same team identified Haumea as a potential dwarf planet from the prints. This was when the discovery was made public. The announcement was also made around the same time that the two known moons of Haumea, Hi’aka and Nakata, were found. In September 2008, Haumea was officially recognised as a dwarf planet and announced as such by the relevant governing bodies.
As an irregularly shaped body, it rotates faster than any other object of its size. It rotates all the way round on its axis every four hours. It is this quick rotation that is responsible for giving Haumea its unusual elongated shape. It is thought that a massive impact started its rapid spinning and a collision was also most probably responsible for the formation Haumea’s moons, Hi’aka and Namaka.
Hi’aka is the outer satellite of Haumea. Orbiting the dwarf planet in 47 days, it is the larger and brighter moon of the two. Namaka is the smaller moon. It completes an orbit in just 18 days and is the moon which is closest to Haumea.
Haumea is named after the Hawaiian goddess of childbirth and fertility. The two moons are named after Haumea’s daughters. Hi’aka is the goddess of Hawaii while Namaka is the name of a water spirit in the mythology of the islands. This is appropriate as Hi’aka and Namaka are thought to have been part of Haumea until an impact separated them from the main body.
Haumea’s composition is primarily rock which is covered with a thin layer of ice. In 2005, astronomers collected data which suggested crystalline water-ice features. It is one of the brightest dwarf planets after Pluto and Makemake. The light emitted from Haumea’s surface is variable due to its unusual shape. Predominantly seen as having a bright white surface, patches of dark red have also been observed on various occasions. This is indicative of carbon-rich substances being present on the surface of the dwarf planet.
Haumea orbits the Sun every 285 years. Along with the other dwarf planets, Eris and Pluto, Haumea is found in the Kuiper Belt, which is an area that lies past Neptune’s orbit containing many icy objects. Haumea is therefore technically known as a Plutoid, which is a word used to describe any dwarf planet in this region of space.