HUBBLE FINDS 'TENTH PLANET' IS SLIGHTLY LARGER THAN PLUTO

PRESS RELEASE NO.: STScI-PR06-16

HUBBLE FINDS THAT THE 'TENTH PLANET' IS SLIGHTLY LARGER THAN PLUTO

NASA's Hubble Space Telescope has resolved the "tenth planet," nicknamed
"Xena," for the first time and has found that it is only just a little
larger than Pluto. Though previous ground-based observations suggested
that Xena was about 30 percent greater in diameter than Pluto, Hubble
observations taken on Dec. 9 and 10, 2005, yield a diameter of 1,490
miles (with an uncertainty of 60 miles) for Xena. Pluto's diameter, as
measured by Hubble, is 1,422 miles.

Xena is officially catalogued as 2003 UB313. It is the large object at
the bottom of this artist's concept. A portion of its surface is lit by
the Sun, located in the upper left corner of the image. Xena's
companion, Gabrielle, is located just above and to the left of Xena.

For electronic images and additional information about the research on
the Web, visit:
hubblesite.org/news/2006/16
www.nasa.gov/hubble

For more information, contact Robert Tindol, California Institute of
Technology, Pasadena, CA, (phone) 626-395-3631, (e-mail)
tindol@caltech.edu, or Mike Brown, California Institute of Technology,
Pasadena, CA, (phone) 626-395-8423, (e-mail) mbrown@gps.caltech.edu .

The Hubble Space Telescope is a project of international cooperation
between NASA and the European Space Agency. The Space Telescope Science
Institute in Baltimore conducts Hubble science operations. The Institute
is operated for NASA by the Association of Universities for Research in
Astronomy, Inc., Washington.

Now that's BIG news, there will be a lot of talk / argument for years to come now....

Keith..

Now that's BIG news, there will be a lot of talk / argument for years to come now....

Keith..

I doubt it. It's been estimated a 1.5 times the mass of pluto since last year.

The IAU isnt going to change its stance on pluto I dont think, I havent heard anything about the IAU working group on naming things for awhile now (since Guy Consolmagno mentioned it at his talk in Gonzaga). But it probably wont classify any more of these rocks as planets.

Pluto should stay a planet for historical reasons if none other.

Who cares what they are called really though. A rose by any other name and all that...

Cheers,
~Al

Al - I beg to differ Irrespective of whether the IAU come up with a naming solution that includes Xena ( :roll: ) as a new planet or consigns it to a lesser body group will not dampen the chatter and argument for a long time. Every time its mentioned in an article (for the forseeable future) it will either be as:

1. Xena, the newest addition to the planetary system or
2. Xena, the planet that isn't a planet...

And I bet your bottom dollar that as more and more data is gathered on its orbit, size, compostion etc etc, comparisons with Pluto etc will always abound.

I think the release above marks a critical difference in pasts data. Estimates have been confirmed. Hubble has determined conclusively for the first time that, even including errors, Xena is definately larger than Pluto. Before now, it was all estimates and 'possibles'.

I agree with you on the facts that Pluto should be not be relegated and what they ultimately call Xena will be p[retty much irrelevent (to me personally). But like Keith, I think this one is set to run and run....

Look - we're doing it now

Cheers!

Dave

Hi guys,

My view on all this is that now that Xena / UB313 has now been confirmed as larger than Pluto, it should be classified as the tenth planet. Pluto could be set as the minimum requirement for a planet in terms of size etc and if any other bodies bigger than Pluto out in the Kuiper Belt are found - then they would become planets also.

Otherwise you reclassify Pluto and all the Kuiper Belt objects in to their own separate category. This means there would 8 planets or ?? planets.

Neill

Hi guys,

My view on all this is that now that Xena / UB313 has now been confirmed as larger than Pluto, it should be classified as the tenth planet. Pluto could be set as the minimum requirement for a planet in terms of size etc and if any other bodies bigger than Pluto out in the Kuiper Belt are found - then they would become planets also.

Otherwise you reclassify Pluto and all the Kuiper Belt objects in to their own separate category. This means there would 8 planets or ?? planets.

Neill

i think we should demand the IAU sort it out pronto. just think of all the poor astrologers having to cast and recast their horrorscopes depending on which way the wind blows .
stephen.