The Dwarf Planet Haumea

The Dwarf Planet Haumea

Haumea is a dwarf planet located in the Kuiper belt.  The little planetoid was discovered in December 2004 by a team of Caltech astronomers.  It is about a third the size of Pluto.  The team initially called it “Santa” but, in keeping with the IAU’s naming convention for Kuiper belt objects they eventually named the worldlet after a matronly fertility goddess from Hawaiian mythology.

Artist's conception of Haumea and its pink spot

Artist’s conception of Haumea and its pink spot

Although Haumea is typical of other dwarf planets in the Oort cloud in that it is a hunk of rock covered with ice, there are a couple of very unique things about the body.  Most notably Haumea is shaped like a lozenge (as opposed to being mostly spherical like other planets).   Astronomers believe that Haumea has sufficient gravity to overcome the compressive strength of its material.  In other words it chould be approximately spherical, however the planet is rotating with such velocity that it has become spindle shaped—like a water balloon thrown in a rifling spiral.

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The extreme rapidity of Haumea’s rotation is its other defining characteristic.  It rotates more rapidly than any planetlike object with a diameter greater than 100 kilometers.   Haumea rotates completely every 3.9 hours so days there are incredibly short (although its huge orbit takes 283 years to complete—so years are long).  It is believed that Haumea’s breakneck spin comes from a titanic collision with some other Oort belt object.  Haumea’s two dinky moons were probably also created by the impact.  Haumea has a large red spot on it–perhaps because of the presence of minerals–or the fractured perturbance left by an impact.