Haumea (Dwarf Planet) - Haumea (Paperback)

Chapters: Haumea. Source: Wikipedia. Pages: 29. Not illustrated. Free updates online. Purchase includes a free trial membership in the publisher's book club where you can select from more than a million books without charge. Excerpt: Haumea, formal designation 136108 Haumea, is a dwarf planet in the Kuiper belt. Its mass is one-third the mass of Pluto. It was discovered in 2004 by a team headed by Mike Brown of Caltech at the Palomar Observatory in the United States and, in 2005, by a team headed by J. L. Ortiz at the Sierra Nevada Observatory in Spain, though the latter claim has been contested. On September 17, 2008, it was designated a dwarf planet by the International Astronomical Union (IAU) and named after Haumea, the Hawaiian goddess of childbirth. Haumea's extreme elongation makes it unique among known trans-Neptunian objects (TNOs). Although its shape has not been directly observed, calculations from its light curve suggest it is an ellipsoid, with its greatest axis twice as long as its shortest. Nonetheless, its gravity is believed sufficient for it to have relaxed into hydrostatic equilibrium, thereby meeting the definition of a dwarf planet. This elongation, along with its unusually rapid rotation, high density, and high albedo (from a surface of crystalline water ice), are thought to be the results of a giant collision, which left Haumea the largest member of a collisional family that includes several large TNOs and its two known moons. The nominal libration of Haumea in a rotating frame, with Neptune stationary. (See 2 Pallas for an example of non-librating.)Haumea is a plutoid, a technical term used to describe dwarf planets beyond Neptune's orbit. Its status as a dwarf planet means it is presumed to be massive enough to have been rounded by its own gravity but not to have cleared its neighbourhood of similar objects. Although Haumea appears to be far from spherical, its ellipsoidal shape is thought to result...More: http: //booksllc.net/?id=233372