'Dwarf planet' covered in crystal ice

2011-05-13 07:26
Paris - A bizarre mini-planet that orbits the Sun in deep space is covered with crystallised water, European astronomers reported on Thursday.

Around 2 000km long, the "dwarf planet" of Haumea lurks in the Kuiper Belt, which comprises rocks that move in a lonely orbit beyond Neptune.

Haumea, named after a Hawaiian goddess of fertility and childbirth, was discovered in 2004 but detailed views of it are very rare and even now its precise orbit and size are unknown.

New sightings by a team from the European Southern Observatory (ESO) using a giant telescope in the Chilean desert describe Haumea as having the shape of a "flattened rugby ball".

Despite its immense distance from Earth, Haumea shines brightly in space thanks to a reflective surface of water ice that covers a rocky body.

Energy sources

Three-quarters of Haumea and all of Hi'iaka, one of two satellites along with Namaka, have this icy coating, ESO said. The ice is unusual because it is crystalline, meaning that it has an ordered structure, it said in a press release.

Crystalline structures are destroyed by sunlight, so other energy sources are needed to keep the ice organised on Haumea and Hi'iaka, rather than meld into shapeless, amorphous frost.

The ESO scientists believe that two sources are available for doing this - a trio of radiogenic elements (potassium-40, thorium-232 and uranium-238) that lie beneath the icy crust and "tidal forces" provided by the gravitational give-and-take between Haumea and her daughters.

Haumea spins completely in less than four hours, giving it one of the fastest rotation speeds in the Solar System.

The mini-planet's strange shape may derive from the ultra-fast spin, which could have been conferred by a tangential collision with another space rock.

The whack could also have gouged out two splinters which became Hi'iaka and Namaka.

It is the fifth largest "dwarf planet", a category that was created in 2006 by the International Astronomical Union (IAU) and is headed by Pluto, which was formerly designated a full-fledged planet.

The two satellites of Haumea are named after the goddess' daughters. Hi'iaka measures around 400km across, and Namaka is around 200km.
Read more on:    astronomy

Join the conversation!

24.com encourages commentary submitted via MyNews24. Contributions of 200 words or more will be considered for publication.

We reserve editorial discretion to decide what will be published.
Read our comments policy for guidelines on contributions.

linking and moving

2015-04-22 07:36

24.com publishes all comments posted on articles provided that they adhere to our Comments Policy. Should you wish to report a comment for editorial review, please do so by clicking the 'Report Comment' button to the right of each comment.

Comment on this story
Comments have been closed for this article.

Inside News24


South African woman learns to surf at aged 70

Anthea Petzer just wants to learn how to stand on her yellow Australian surfboard and carve up the waves.



Extreme Kiteboarding in Pumping Conditions!
The Arctic becomes an unlikely surfing hotspot
A romantic holiday to beat the winter blues
Why should you do a 5k?

Book flights

Compare, Book, Fly

Traffic Alerts

The moon moves out of your sign this afternoon highlighting the need to connect to your deeper emotions and absorb all the...read more

There are new stories on the homepage. Click here to see them.


Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.

Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire 24.com network.


Location Settings

News24 allows you to edit the display of certain components based on a location. If you wish to personalise the page based on your preferences, please select a location for each component and click "Submit" in order for the changes to take affect.

Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.