Scientists: '10th planet' only slightly larger than Pluto (AP/CNN)

[eppur_se_muova]

Wednesday, April 12, 2006; Posted: 2:33 p.m. EDT (18:33 GMT)

LOS ANGELES, California (AP) -- An icy ball discovered last year in the outer solar system is only slightly larger than Pluto, casting doubt on previous estimates that the so-called 10th planet was significantly larger, scientists reported Tuesday.

Previous estimates by ground-based telescopes suggested the object known as 2003 UB313 was 30 percent bigger than Pluto.

But the latest measurement by the Hubble Space Telescope has a smaller margin of error and is probably a more accurate estimate, said lead researcher Michael Brown of the California Institute of Technology.

According to Hubble, UB313's diameter measures 1,490 miles (2,397 kilometers), give or take 60 miles (100 kilometers). Pluto is about 1,422 miles (2,288 kilometers) across.
***
more: http://www.cnn.com/2006/TECH/space/04/12/10th.planet.ap/index.html

But it's still smaller than Uranus.

[darkmaestro019]

1. WHAT is this so-called business?

:nuke: WHY WHY WHY

It's a PLANET, you dolts. Take your so-called article and and see if you can find a so-called copy editor who can fix your so-called writing!

Spare me the whining about the size thing. If it's in an independent orbit around the sun, it's a planet. If you have some kind of weight-category rule, then call it a planetoid or something. Don't you guys have word-counts? Or grasp that it's generally considered good writing not to use unnecessary words?



:argh:

EDIT: That's not directed at you, OP, I promise. And thank you for the article anyway, I dearly love various forms of space/science news. Badly written or otherwise. : )

[cosmic _mind]

3. I don't think i'd blame the writer either...

Isn't it the scientists who are bickering over how to classify this? Some don't even think Pluto should be considered a planet. As for the independent orbit - what about asteroids? Personally i would like to see someone authoritatively come out and say let's just call it a planet and be done it. But then, the discoverer wants to call it Xena. Seriously now, if you're gonna name a planet after a fictional tv character, it better be Kirk or Spock or even Picard! Xena?? Give me a break...;)

[darkmaestro019]

4. ha! I heard about that--

I know it's scientists in this case, but "so-called" (or those dang quotes) is always someone bickering over whether something is real or not and it drives me absolutely insane. If it's a hologram use the quotes--otherwise just say what you're saying and be done!

Xena?

I know she went all over Hell and Creation literally, ha, but I don't remember seeing her in space...

I'm voting for Spock or Picard : ) for childhood's sake. For seriousness, I'd suggest Proserpina though I think they used that already for something. Though we've already messed up our own theme, with Earth not being called Gaea--and why in the world did we go with the Roman copycats and not the Greek originals? :shrug:

That's a good point about the asteroids...how about, independent orbit, and a certain gravitational ability? I'm not sure what they use to decide, and apparently, neither are they.

[htuttle]

6. I think I read that they wanted a name that started with "X"

And since Pluto is technically named after a cartoon character, not a Roman god (seriously -- look it up...), they figured it would be acceptable to use the name of a TV character.

Or so I read shortly after they name it. No link handy, though.

[electron_blue]

11. it's not up to science writers to declare something a planet

And in fact, most planetary scientist would put UB313 & Pluto in the category of Kuiper Belt Objects, which all have independent orbits around the Sun.

I'm just sayin'.... calm down a little bit.

[Systematic Chaos]

2. Don't get me wrong - I love astronomy

But exactly HOW fine a point do we need to put on the diameter of some chunk of ice over 4 billion miles away? :eyes:

[sutz12]

5. Maybe it's the 'chunk of ice' thing

Perhaps some think a 'real' planet should be made of rock or be a gas giant like Jupiter, et al?

Just throwing out a question. I guess some would like to call it an oversized comet or something.

I thought they had some kind of convention or a commission for naming and labeling or something. Maybe the Repubs dismantled that one too.

[Solon]

7. Actually, that could be problematic...

Ceres, the largest Asteroid is like most other asteroids, mostly rocky Iron/Nickle with some Carbon thrown in. Personally, I would categorize actual planets as being objects in orbit of a Star that have enough Mass for a SIGNIFICANT atmosphere. All planets except perhaps Pluto would qualify for this, and remember, they all orbit the Sun, so they are planets, the only Moon in the Solar System with a significant atmosphere, Titan, orbits Saturn. Actually, remember, almost all the moons and smaller planetoids, like our own Moon have an atmosphere, but its practically insignificant, unlike even Mars, which only has an atmosphere that's one percent the pressure of Earth's at Sea Level.

Also, labeling is actually more complex than most people realize, Asteroids are objects that are rocky and most are present in either the Main Asteroid Belt or the smaller one further out in the Solar System. Some have eccentric orbits, but are still rocky and are Asteroids, and become Meteors when they fall onto a planet. A comet is an object mostly composed of ices(Water, Methane, Carbon Dioxide, etc.), and is in an eccentric orbit where it outgasses those ices when it comes close to the sun. Pluto, and all the other objects that are THAT far out and don't fall into the inner Solar System are Kuiper Belt Objects(KBOs), I didn't even mention the Oort Cloud, which is even further out, about 2 light years, half the distanct to Proxima Centauri the the Kentaurus Binary star system.

[sutz12]

8. Thanks for the clarifications, such as they are.

:)

[NNadir]

10. Your criteria would exclude the planet Mercury.

The existence of an atmosphere depends very much on temperature.

Pluto does, depending on the time of year, apparently have an atmosphere.

http://web.mit.edu/newsoffice/2003/pluto.html

[Solon]

12. See, that's the problem with trying to come up with "clean"...

classifications at all. Nature generally never agrees with it, too damned messy, but we humans LOVE labeling things. Hell, we could use other criteria besides atmosphere, if we were to say it had to have a Magnetosphere, as an example, Mercury is back in, but Venus and Mars, in addition to Pluto are out. To hell with it, let's just say that all objects that orbit the Sun are planets, that would give it what, about a trillion planets orbiting it?

[eppur_se_muova]

13. There's the whole point...all classifications are more or less arbitrary.

I'm just interested that we're getting more info about the Solar System.

[Odin2005]

9. The "is it a planet" arguments are rediculous

of course Pluto and Xenia are planets, but then so are Ceres, Sedna, Eros, and Halley's Commet, but they are all MINOR planets. the problem is were to set the line betweena major and minor planets. I like the suggestion by, IIRC, Isaac Asimov, to create an intermediate catagory called "mesoplanets."