8 planets, not 9. Deal with it. (no spam)

[fable]

AP, PRAGUE, Czech Republic (Aug. 24) - Leading astronomers approved historic new planet guidelines Thursday -- downsizing Earth's neighborhood from nine principal heavenly bodies to eight by demoting distant Pluto.

cosmos, the International Astronomical Union stripped Pluto of the planetary status it has held since its discovery in 1930. The new definition of what is -- and isn't -- a planet fills a centuries-old black hole for scientists who have labored since Copernicus without one.

Fans of Pluto, which was discovered in 1930, are expected to go into orbit with the International Astronomical Union's decision to downgrade it. But under pressure from opponents, the organization has backed off its original plan to retain Pluto's status and bring three other objects into the cosmic club.

If the 2,500 astronomers from 75 nations meeting in Prague agree, Earth's neighborhood will officially shrink to eight planets from the traditional nine. "There would be only eight planets, plus the dwarf planets," said Japanese astronomer Junichi Watanabe, a member of the IAU's planet definition committee...

Resolutions being considered by the group, the official arbiter of heavenly bodies, would define a planet as "a celestial body that is in orbit around the sun, has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a ... nearly round shape, and has cleared the neighborhood around its orbit." Anything less would be either a dwarf planet, as in Pluto's case, or a "small solar system body," which would cover many asteroids, comets or other natural satellites...

Astronomers want to draw a sharp distinction between the eight "classical planets" - Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune - and Pluto, which is smaller than Earth's moon, no larger than many objects in its area and has an eccentric orbit. Joining it as dwarfs would be its largest moon, Charon; the asteroid Ceres, which was a planet in the 1800s before it got demoted; and an object known as 2003 UB313 recently discovered by Michael Brown of the California Institute of Technology in Pasadena, Calif. Nicknamed Xena, it is a slightly larger Kuiper Belt object.

Just a week ago, all three objects were poised to become planets under an initial draft definition that would have created a new class of planetary objects to be dubbed "plutons." But that idea left many astronomers cold, triggering days of spirited and sometimes combative debate that led to the latest proposal to dump Pluto. Many believe there's simply no scientific justification to grant full planet status to most of what's floating in the vast sea of rocks that reside in the Kuiper Belt - a mysterious, disc-shaped zone beyond Neptune containing thousands of comets and planetary objects.

Forget the term "pluton" - it's already history, replaced by "plutonium object." The IAU backed off after getting dozens of objecting e-mails from scientists, including geologists who pointed out - somewhat embarrassingly to astronomers - that "pluton" is already a prominent term in volcano science for deep igneous rock formations.

"What were they thinking?" said Allen F. Glazner, a geologist at the University of North Carolina. "It would be like botanists trying to distinguish between trees and shrubs and coming up with the term 'animal."'

[Xandax]

(Arrrg - here I was about to start posting the same thing and you stole it from me... grrrr.)


I can fully understand "them" and the need for classification of objects.
If Pluto was a planet, many other rocks would be as well, as they also mention in the article, and we'd have 12 planets so far in our solar system, and likely many more.
As for actual consequence, well then there isn't really any other then how we define the universe.
Astrologists would likely be the most hit by this (), but many in Denmark have already said that they would not stop calculating with Pluto because it has a large effect on people. And I'd almost expect such a opinion is pretty worldspread for such a field.

[Dowaco]

I think it was a good decision. As was pointed out, if Pluto is a planet then others would have to be as well. I can live with 8 planets.
All they have done is to create a new classification of small solar system bodies (SSSBs?) to gather up the larger objects into one pot. Pluto now fits better in this class then with the big boys.

[fable]

Originally Posted by Xandax

(Arrrg - here I was about to start posting the same thing and you stole it from me... grrrr.)

I live to serve.

Astrologists would likely be the most hit by this (),

In fact, Radio Nederland had an astrologist on a month or two ago when a Pluto-like object was discovered, and it was thought we'd have 10 planets, rather than 9. He was expansive, claiming that astronomers are now proving what astrologers have known all along, of course: that there are actually 12 planets, and we're playing catch-up. Of course, now that we're down to 8, the astrologers will probably shrug, complain about "blind scientists," and go on studying their charts that were out of date thousands of years ago. At least, such is my opinion, based on the fact that their first sign, Aries, is now several months into the year, instead of at its start, as it was when Babylon was staring at the skies.

[dragon wench]

IMO it's just semantics anyway, but I'm no astronomer

Seriously, I've taken a few courses in astronomy because it interests me, and from what I recall the distinction between moons and planets, not to mention all of those other lumps of rock in the galaxies, is a very grey area.

[VonDondu]

The traditional view of the solar system--i.e., a star with a few large objects in orbit on a single plane--has already been dismissed for good. Now we know that there are at least 180,000 sizable objects circling the sun and countless dust particles and other small objects. It just isn't a clean, neat diagram anymore.

Resolutions being considered by the group, the official arbiter of heavenly bodies, would define a planet as "a celestial body that is in orbit around the sun, has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a ... nearly round shape, and has cleared the neighborhood around its orbit."

I still see problems with this new definition. The last part about clearing the neighborhood around its orbit helps to clarify the distinction between the "classical planets" (which have supposedly cleared the neighborhood around their orbits) and Pluto (which has many "neighbors" in the Kuiper Belt). But the terminology is very imprecise. For example, what about moons? Can we really say that Jupiter has "cleared the neighborhood around its orbit" when it has at least 63 moons that we know of? Jupiter is surrounded by "neighbors" that it hasn't gobbled up. Saturn, with its famous rings, is even worse. The rings might look like pretty discs from a telescope, but they're actually a mess. What about the Earth itself (gasp) which is gradually losing its own moon (it will no longer circle the Earth in a few billion years)?

Besides, in the case of the inner planets, do they really deserve all the credit for clearing their respective neighborhoods? They never would have made it on their own if they were stuck in the Kuiper Belt. They had so much help from the sun, we're looking at favoritism on an astronomical scale.

On the flip side, doesn't Pluto deserve some credit for capturing a moon of its own? Essentially, Pluto is being discriminated against for being so far away from the sun. I really don't know the answer to this question, but how far away is Pluto's closest neighbor (excluding its own moon like all the other planets get to do, of course)? Is it any closer than the Earth's closest neighbor (not counting the Moon)? Are we saying that Pluto isn't a planet just because some object crosses its orbital path from such a distance that not even Jupiter could snag it up? If that's the case, then a planet's status essentially depends on its location, not merely on its own physical attributes. If you put Venus in the Kuiper Belt, it wouldn't be a planet anymore because there's no way it could ever clear the neighborhood around its new orbit. This definition stinks of cronyism, and I have a problem with it.

I'm not suggesting that we should call Pluto a "planet" just because some people want it to be called a planet or because we have sentimental reasons or because we've called it a "planet" since 1930 and we shouldn't change now. All I'm saying is that the new definition of "planet" leaves a lot to be desired and I would like to see it clarified with better, more precise scientific language.

[Aegis]

I am inclined to agree with you, VD. The new definition seems to do little to clear up the murky waters that already exisited within this issue. In fact, without going over what has already been said again, it almost appears as though the astronomical community is deflecting the whole issue.

[Masa]

I couldn't care less about pluto being a planet or not. It doesn't change anything.

[mr_sir]

I'm not that bothered by the fact there are only 8 planets but I feel sorry for all the writers of science text books and teachers as all their materials will be wrong

I've never really understood what makes a planet a planet rather than just a big rock in space. The thing that makes me curious is what would they do if they ever discovered evidence of life on these 'rocks'. Would they then be classed as a planet or just a rock with life on it? I can understand classifying rocks as moons if they orbit a planet, but how do they decide if something that orbits a star is actually a planet? It must be a pretty hard thing to classify.

[Chimaera182]

I'm really with Masa on this one. Pluto could be classified as a sun or a neutron star or a black hole, it doesn't change anything. People really don't need to be focusing so much on the outside when they should really be focusing within.

mr_sir: if a mass had life on it, it wouldn't change its classification. The presence of life doesn't change whether a planetary body is a planet or a moon; if humans develop cities on the moon like in several science fiction books/shows/movies, that won't make the moon a planet. The guidelines are based on the physical make-up of the "rock" itself. To draw from Star Wars, both Yavin IV and Endor were teeming with life, but they were still just moons, but then that's science fiction after all and can just as easily be wrong. But I just don't see astrologists calling a moon a planet just because there's life on it.

[VonDondu]

Originally Posted by mr_sir

I can understand classifying rocks as moons if they orbit a planet, but how do they decide if something that orbits a star is actually a planet? It must be a pretty hard thing to classify.

Um, that's what this discussion is all about.

Originally Posted by Chimaera182

mr_sir: if a mass had life on it, it wouldn't change its classification. The presence of life doesn't change whether a planetary body is a planet or a moon... The guidelines are based on the physical make-up of the "rock" itself...

That's not correct. The previous guidelines that dealt strictly with an object's physical characteritics (namely, having enough mass to make it round) never settled the question of whether Pluto or other Kuiper Belt objects should be called "planets". Under the old guidelines, even some of the moons out there were big enough to be called "planets". That was the whole problem. The new guidelines also include the stipulation that a "planet" is an object that "has cleared the neighborhood around its orbit". That has nothing to do with the physical make-up of the "rock" itself.

The way I read it, we're also talking about the location of the "rock" and its proximity to neighboring bodies, since only "rocks" that were lucky enough to be close enough to the sun to end up by themselves in their own "neighborhoods" can qualify as "planets". (For some reason, moons don't count as "neighbors".)

[Xandax]

Originally Posted by Chimaera182

I'm really with Masa on this one. Pluto could be classified as a sun or a neutron star or a black hole, it doesn't change anything. People really don't need to be focusing so much on the outside when they should really be focusing within.
<snip>

Well neither does defining a tree as a tree instead of a fish, yet we define every single aspect of existance we can, and lable it to create a common ground of understanding and communication.
As for what actual effect this will give - if any - is hard to predict, but currently I think the consequences are rather limitied, yet it is about the same to me as when they named a tree a tree.

I do however from a person interested in space and such find it interesting and fascinating that we now only have 8 planets in our solar system, as I would have if we suddenly had 12. (I'm more happy with 8 then 12, but mostly because it is easier to remember the names of the 8 then of the 12 )

[mr_sir]

Originally Posted by Chimaera182

mr_sir: if a mass had life on it, it wouldn't change its classification. The presence of life doesn't change whether a planetary body is a planet or a moon; if humans develop cities on the moon like in several science fiction books/shows/movies, that won't make the moon a planet.

What I meant was, what if in the future they discovered evidence of life forms on Pluto? Would this make them reconsider if it is a planet or just a giant oversized rock? Humans suddenly inhabiting a moon is a different situation. Its also different if there is evidence of life found on an asteroid or comet. I'm meaning a rock which is on the borderline between not being a planet and being a planet.

[fable]

Originally Posted by mr_sir

What I meant was, what if in the future they discovered evidence of life forms on Pluto? Would this make them reconsider if it is a planet or just a giant oversized rock?

Not if I underdstand this change correctly. They appear to be trying to come up with a formula for separating the planets created at the time of the solar system's formation from those objects that were "caught" from elsewhere, or spun out of a planet's orbit. So if life was discovered on a mini-planet, or a rock, or in the United States Congress, it would still count as life, however unusual that occurence might be.

[Rein]

Originally Posted by Chimaera182

People really don't need to be focusing so much on the outside when they should really be focusing within.

i've always been interested in the universe, and to hear that they are trying to classify objects in space gives me hope for the future. i don't agree with just focusing within. if that was the case then we would live our lives never going further than our solar system. the human race (because i belive in aliens) in conjunction with the earth, would be sheltered. that is if you could take in the possibility of other solar systems that are more advanced in their solar system evolution. And assuming that there could be other life that is overall further along in their planetary life span that got further into space than the pathetic evolution of our planet. Eventually the earth will be gone or life will cease, and tell me if i am right, the sooner we develope better technology the sooner we can prepare to evacuate this planet if need be. this of course wouldn't happen during our life but would benifit the existence of our race millions or billions of years from now.

i think that we need to get out there into the unknown and discover life already. pluto aroused many subjects and influenced many thoughts for discovering the creation of want to learn ethics. thats just my opinion though.

What if the human race survived the ultimate hazard, pluto could be on the flag that stands for the way we live (chaotic but with purpose) and the reason we will continue to live.