Discovery date December 28, 2004
Orbital period: 285.4 years
Moons: 2 (known)
Dimensions: ~1,960×1,518×996 km
Average diameter: ~1,500 km
Mass: (4.2±0.1)×1021 kg
Mean density: 2.6–3.3 g/cm³
Equatorial surface gravity: 0.44 m/s²
Rotation: 3.91 hours
Temperature: 32±3 K
Apparent magnitude: 17.3
Haumea (pronounced: how-MAY-a ). Named for a Polynesian fertility goddess, shaped like a rugby football, and spinning around on its axis once every four hours, the last-named of the new planets is cold, enigmatic, and for astronomers controversial.
Named on September 17, 2008 after years of astronomical controversy surrounding her discovery, Haumea is by far the most eccentric and enigmatic of the new planets discovered beyond Pluto.
Briefly, the discovery controversy goes back to Dec 24, 2004 when California astronomer Mike Brown (no relation to your humble webmaster) and his colleagues discovered Haumea (and promptly nicknamed it Santa pending a final name). Brown and his group of astronomers also discovered the other five new planets discussed on this website.
Being altogether too trusting a soul, astronomer Brown and his team posted their technical data on the location of the planet in an obscure corner of their website. That data was then snitched by a Spanish team of astronomers who, using the Brown data to find Haumea, promptly claimed they had found the new planet.
Years of uproar ensued, peppered by bursts of nasty accusations and counter-accusations amongst the astronomers. Understand that astronomers have egos bigger than the orbits of the outer planets, and who gets credit for a discovery of a new planet is a very big deal in the astronomical profession.
In the end the International Astronomical Union, based in Paris, France, (the de facto arbiter of these sorts of things) accepted the planet name, Haumea, proposed by Brown, et al, a tacit acknowledgement that the IAU accepted that the Brown team were, in fact, the planet's discoverers.
Meanwhile, we astrologers had to wait patiently for this clash of scientific egos to resolve itself, for it is not until a new planet is both discovered and named that astrologers can get on with the business of determining the meaning of the planet and it's place in the metaphysical scheme of things.
The science of Haumea is fascinating in and of itself and leads us to the astrological meaning of the planet. Haumea's orbit is tilted on an angle, elliptical, and long. It takes Haumea 285 years to go around the Sun once. Compare that to Pluto's orbit of 248 years, and you can see Haumea is considerably further away from the Sun than Pluto, and hence a lot colder.
The Jet Propulsion Laboratory at NASA, which tracks planetary orbits amongs other things, has an interesting webpage illustrating Haumea's orbit. Click here for that page, providing your browswer supports java script. Note that NASA still uses the old temporary astronomical designation of 2003 EL61 to identify Haumea.
More unusual than Haumea's elliptically shaped orbit is the shape of the planet itself, similar to the shape of a rugby football. For Americans, this is similar to the elliptical shape of a US football, but without the pointed ends. Additionally, the planet tumbles end over end every four hours, the fastest rotation of any planet in the solar system. (See the animation at the top of this page which illustrates the rotation.)
See Wikipedia for details about Haumea's discovery controvery and scientific characteristics.
The science gets stranger. Haumea is virtually solid rock with a thin coat of water ice on the outside, and has two moons. Additionally, several smaller planetoids are in the same orbital path as Haumea, leading scientists to conclude that Haumea was once a larger planet, but due to an ancient collision, got broken up into smaller pieces which are still orbiting in the neighbourhood.
It was the breakup of planet in the hypothesized ancient collision (of unknown origin) which led scientists to name the planet Haumea.
Haumea's uniqueness doesn't end there. By 2017 researchers from the EU-funded project LUCKY STAR announced they had discovered that Haumea had a small ring around it, not as dramatic as the rings of Saturn, mind you, but a measureable ring nonetheless.
The ring is estimated to be 290 Km in radius, 70 Km in width and with a 50 % opacity. Prior to this discovery astronomers had thought that rings were principally to be found around the four outer planets of Jupiter, Saturn, Uranus and Neptune, although by 2014 a few of the Centaur bodies were discovered to have rings.
The ring rotates around the planet three times more slowly than the 3.9-hour rotation period of the planet itself. Likely the ring is made of rock and ice, and some astronomers speculate these frozen particles could be a result of the debris created by the impacts from stray rocks...well, maybe.
Another theory is the ring might have been created by the planet itself, as Haumea spins unusually fast and so it might be hurling particles out into orbit. If Haumea is doing that, then it's throwing all those bits and pieces out there quite a ways as the ring is about 1000 Km away from the planet.
The naming of Haumea is equally interesting. In one of his webpages astronomer Brown says:
"Haumea is the goddess of childbirth and fertility in Hawaiian mythology. Her many children sprang from different parts of her body. She takes many different forms and has experienced many different rebirths. As the goddess of the earth, she represents the element of stone.
"The name was chosen by David Rabinowitz of Yale University, one of the co-discoverers of Santa (along with me and Chad Trujillo of Gemini Observatory in Hawaii). He chose the name because Haumea is closely associated with stone, and Santa (as we knew it at the time) appeared to be made of nothing but rock.
"But the name is even better than that. Just like the Kuiper belt object Haumea is the central object in a cloud of Kuiper belt objects that are the pieces of it, the goddess Haumea is the mother of many other deities in Hawaiian mythology who are pieces pulled off of her body."
For an extensive discussion of Haumea's mythology, click here. This is the online Haumea chapter from Martha Beckwith's landmark 1940 book, Hawaiian Mythology, the entire version of which can be read here.