IAU Rules Pluto Still a Planet 244
scottyscout writes "NPR reports that Pluto has dodged a bullet.
An international panel has unanimously recommended that Pluto retain its title as a planet,
and it may be joined by other undersized objects that revolve around the sun.
Some astronomers had lobbied for reclassifying Pluto as its so tiny. And at least one major
museum has excluded Pluto from its planetary display. But sources tell NPR that under the
proposal, to be presented at a big meeting of astronomers in Prague next week for a vote,
Pluto would become part of a new class of small planets and several more objects could be
granted membership."
If they have such power,,, (Score:2, Funny)
Re:If they have such power,,, (Score:5, Informative)
Re:If they have such power,,, (Score:2, Flamebait)
Xena is a warrior princess, she's hot so she gets to be a planet. The other celestial objects sound ugly, I would never date a Sedna, unless she gave good head.
parent post overrated (Score:5, Funny)
Re:parent post overrated (Score:3, Funny)
*Goes back to masturbating to a Night Elf*
Re:If they have such power,,, (Score:5, Insightful)
Re:If they have such power,,, (Score:4, Interesting)
Various people (not generally astronomers) want a strict, reasonable definition of "Planet", but find that these either exclude Pluto, or include a vast number of things no one would really consider a planet.
Astronomers generally don't care. They know Plutos properties, and don't use "planet" as a terribly specific term. This is purely a laymans controversy. It's significant only because something you learned in grade school was an over-simplification. Experts understand the details, and exactly which over-simplification is better is not very interesting to them.
But since I'm a layman, my 2 cents:
Juptier and Earth aren't like each other. They also aren't like anything else in their repsective orbital neighborhoods. There's a whole lot of stuff that orbits the sun at roughly the same distance as Earth, and none of it is much like Earth. Ditto for Jupter and 6 other object whose names you know. There's a whole lot of stuff that orbits at similar distance as Pluto, and quite a bit of it is a lot like Pluto.
Somewhere in there is my own favorite over-simplification, which kicks out Pluto.
Preserve it for Posterity (Score:3, Funny)
I "relate to its inadequacy" (Score:5, Insightful)
-Earth's Diameter: 12,756.274 km
-Pluto's Diameter: 2306±20 km
-Jupiter's Diameter: 142,984 km
-Proportion of Earth to Pluter: 12756.274 / 2306 = 5.531
-Proportion of Jupiter to Earth: 142984 / 12756.274 = 11.209
Hmm... Jupiter has over twice the proportional difference with Earth as Earth has with Pluto. So I guess Jupiter wouldn't really consider Earth a real planet.
Personally, I think we should leave the little guy alone. Throw UB313 [wikipedia.org] in there as well. Just give it a cool name that fits in with that whole "my very educated mother..." thing.
Like the well learned and professional scientist said: "We'll call them dwarf planets or something".
--
"A man is asked if he is wise or not. He replies that he is otherwise" ~Mao Zedong
Re:I "relate to its inadequacy" (Score:2)
Re:I "relate to its inadequacy" (Score:5, Insightful)
But, shouldnt we also consider the fact that there is a high probability that pluto was not created from the accretion disk around the sun, from which other planets were formed ?
Especially the plane in which pluto revolves, which is very very different from other planetary planes, should also be taken into consideration, I guess.
A planet should not be just an object which revolves around a star. Rather it is something which should have formed when the star was formed. This we can very easily judge (provided we know) from the heavy metal content and the ratio, I guess.
But, I guess these should have been easily the first points in IAUs discussions. Otherwise, I am completely wrong in my assumptions
Re:I "relate to its inadequacy" (Score:5, Insightful)
Couldn't it be argued that the accretion disk includes the Kuiper Belt?
Re:I "relate to its inadequacy" (Score:5, Insightful)
The article also talked about how children would benefit from Pluto's planethood because it's a "misfit". Shouldn't we be classifying planets based on it's characteristics, not how it affects our culture or how people relate to it? If we classify things based on how people relate to them, we might as well call whales the "misfits of fish." It might be a totally incorrect classification, but at least obiese people have something to relate to now!
Re:I "relate to its inadequacy" (Score:2)
Well, laymen and astrologers. Care to know what having pluto in the third house means to you?
Excellent picture (Score:2, Informative)
Pluto via Hubble [npr.org]
Re:I "relate to its inadequacy" (Score:5, Funny)
Earth/5.5 = 2300km => Pluto is a planet
Pluto/5.5 = 420km => Vesta asteroid (450km) is a planet
Vesta/5.5 = 82km => 61 Danaë asteroid (82km) is a planet
61 Danaë/5.5 = 15km => 2685 Masursky asteroid is a planet
2685 Masursky/5.5 = 2.5km => 2002 JF56 asteroid is a planet
2002 JF56/5.5 = 455 meters => CN Tower (550m) is a planet
CN Tower/5.5 = 100m => Eyeglass orbital telescope would be a planet
Eyeglass/5.5 = 18m => The Titan Missle silo was a planet
Titan/5.5 = 10.7 feet => Your bathroom is a planet
Bathroom/5.5 = 2 feet => Your Mom is a planet! Oh, snap!
Re:I "relate to its inadequacy" (Score:2)
Ah, but then each object in the Oort cloud could possibly be considered a planet too. Damn.
Re:I "relate to its inadequacy" (Score:2)
Re:I "relate to its inadequacy" (Score:4, Funny)
Bathroom/5.5 = 2 feet => Your Mom is a planet! Oh, snap!
I like the way you reason, but I'd sooner call her a midget.
Re:I "relate to its inadequacy" (Score:5, Funny)
Re:I "relate to its inadequacy" (Score:3, Funny)
Re:I "relate to its inadequacy" (Score:2)
But who asked the Jovians?
We can't really use size relationships as a guideline here, or we could go as small as we wished.
The Plutonias would say a body 1/5th of that planet's size should be a planet too, then.
Ymir was a giant . . . (Score:3, Informative)
Re:I "relate to its inadequacy" (Score:2)
Who are these people, anyway? (Score:2, Funny)
Why should I listen to this "IAU" instead of to him?
Re:Who are these people, anyway? (Score:2)
But that didn't stop it from happening, merely delayed [wikipedia.org] it for 70 years.
The Terrorists are against Pluto... (Score:2, Informative)
All the better. (Score:2, Funny)
All the better to have them converge on Prague without the benefit of the latest in hair care products, and to all end up coiff'ed like Einstein.
Future objects (Score:5, Funny)
In other news, Pixar announces corporate sponsorship of IAU.
Re:Future objects (Score:2)
>
> In other news, Pixar announces corporate sponsorship of IAU.
In a followup to an earlier story, IAU has issued a statement rejecting the Pixar proposal as fucking Goofy.
Re:Future objects (Score:2)
Re:Future objects (Score:2)
Re:Future objects (Score:3, Funny)
Re:Future objects (Score:5, Funny)
That's what I love about Slashdot. Just when I think I can make out the murky bottom of the Marianas Trench with the thread's floodlights, someone shows up with a drill bit.
I don't get it (Score:4, Interesting)
Why not fix the "official" number of planets at nine, including the largest, nearest, and most well-known of the Kuyper Belt Objects, and leave it at that?
Pluto's nature won't change either way, and our understanding of it won't change either way. This kind of legalistic controversy just for the sake of legalistic controversy is getting pretty annoying.
Traditionally, Pluto has been a planet. Now, I'm not saying tradition trumps everything, but I see no reason why it shouldn't trump meaningless debate.
Let me know if I've got it all wrong, and there is actually meaningful debate on this topic.
Re:I don't get it (Score:2)
Assuming the latter is a meaningful debate, yes, there is a meaningful debate on this topic.
Re:I don't get it (Score:5, Interesting)
Because there's nothing the scientific community loves more than controversy, and this is beginning to rival the great Newton vs. Einstein debate, where some purists were not convinced that Einstein's theories were realistic. Clyde Tombaugh [wikipedia.org] discovered Pluto back in 1930 after a systematic search for planets beyond Neptune. He had to pore through photographic plates, trying to find the tiniest relative shift of an object in the starfield that would lead him to a body that was orbiting the Sun. That he found Pluto was remarkable for the time, and I think all this debate over Pluto's status is a disservice to him. Let sleeping dogs lie, let Pluto remain one of the original nine planets, and let's move on.
Re:I don't get it (Score:5, Interesting)
No, actually, I (and most of the astronomers in my peer group) do NOT enjoy the ongoing saga. We would like the whole matter to go away.
The real answer is
Editors know that "telling people that stuff they learned in elementary school is wrong" can pull emotional strings and get a rise out of some people ... and
that leads to profit.
Sigh.
Re:I don't get it (Score:2)
No, actually, I (and most of the astronomers in my peer group) do NOT enjoy the ongoing saga. We would like the whole matter to go away.
But it won't until the member body of the IAU stands up and says "Enough!" This whole controversy required exactly one meeting, where everyone could debate the issue, and then a consensus could be formed and a standard applied. But this has dragged on and on and on. Heck, this was a problem even before the influx of larger KBO's into the public consciousness. Astronomer
Re:I don't get it (Score:5, Insightful)
No, the overwhelming majority of astronomers were not. We don't care. Really. The issue "what is a planet?" has for most of us the same urgency and relevance that "what is a continent?" has for geologists.
There certainly _are_ topics on which there is vigorous debate in the astronomical community -- for example, the nature of gamma-ray bursts, or the accuracy and precision of the cosmological distance scale, or the physics of supernova explosions. But this isn't one of them. The issue exists solely because a very few people who (for some reason) are seeking publicity go to the media periodically with a "new twist" on this question.
Adding the question "is Pluto a planet" to the list of serious astronomical questions of the day does a disservice to those other questions.
Re:I don't get it (Score:2)
Nonsense. (Score:3, Informative)
This isn't even remotely like a dispute between two theories - it's a simply argument over nomenclature and science has no problem at all simultaneously supporting multiple naming conventions.
Re:I don't get it (Score:4, Informative)
I thought the set of planetary "rules" should be generic and work for our solar system to avoid controversies.
Scientists generally hate controversies as far as I know. That's why they try to search for unifying theories and theories that work, instead of keeping to invent random unprofessional theories to challenge other established ones with.
Why not fix the "official" number of planets (Score:2)
Re:Why not fix the "official" number of planets (Score:3, Informative)
"Planet", on the other hand, is an arbitrary term, convenient for differentiating between different types of celestial bodies, but not actually bound to a specific natural phenomenon or physical law or mathematical principle.
As susano said... (Score:2)
It's no big deal, really. No doubt when we reach other stars, we'll classify their planets according to which solar planets they resemble - and that will be as useful as any other definition.
Re:I don't get it (Score:4, Interesting)
However, it may be beneficial to allow political or corporate entities to lay claim to asteroids for purposes of development or mining. In fact, we may state that it is OK to change their orbits for economic gain. Let's decide that we aren't allowed to smash planets (or moons for that matter) into pieces to make mining easier. There are a lot of plans for deflecting an asteroid away from Earth, so can we deflect it to hit Mars instead? It would certainly make it easier to obtain the metals we want if it is already smashed into pieces. Is it OK to deflect it into another asteroid, but not a planet?
While these may seem like useless things to consider, we have learned the hard way that humans tend to exploit environments once they get their hands on them. It is only after destroying large areas that we decide we should protect what's left. Hopefully, we can create a good system to prevent that from happening with other planets and major solar system objects, while still getting the economic benefits of mining in space.
Re:I don't get it (Score:2)
And I have no problem with politicians and their constituents wrangling out a technical political and legal definition of planets, in order to better pursue political and economic gain.
My problem is with everybody thinking that any of this is at all relevant to the historical, social tradition of counting Pluto among the planets, or that we must now change our
Re:I don't get it (Score:2)
Re:I don't get it (Score:5, Interesting)
(If you're in astronomy for the money, you're crazy.)
Re:I don't get it (Score:2)
Pluto was named during The Time of Naming Planets. Therefore, for reasons of history and tradition, we count it among the planets, even though it's also a KBO.
All other KBOs were, or will be, named during The Time of Naming KBOs. Therefore, again for reasons of history and tradition, we count them among the KBOs, even the really big one really far out, that we haven't found yet.
People whose professions require precise technical terminology are still we
And that, in the end (Score:2)
Museum displays... (Score:5, Informative)
Hell, I can show you museums that show kind, gentle dinosaurs living in harmony with man [answersingenesis.org]. So what?
Re:Museum displays... (Score:2)
Hell, I can show you museums that show kind, gentle dinosaurs living in harmony with man. So what?
This museum [answersingenesis.org] is a parody site, right?
That does it! (Score:3, Funny)
Re:That does it! (Score:2)
May I suggest starting by dropping the Holy Hand Grenade of Antioch [wikipedia.org] on them?
Pluto must be happy to hear this... (Score:5, Funny)
Don't we have this covered already (Score:5, Funny)
Re:Don't we have this covered already (Score:2)
I assume the / at the end of the URL was accidental. How did it happen? I'm curious because you're not the only one I've seen do it.
Re:Don't we have this covered already (Score:2)
Thanks. Looking at my own history, I see that I actually do something similar on occasion as well: I would visit http://groups.google.com/group/alt.news.group/ [google.com] even though Google doesn't link to it with trailing slashes. Strange :)
You know... (Score:5, Funny)
Re:You know... (Score:2)
You have the Klingons near Uranus to thank for that.
Re:You know... (Score:2)
My suggested name is 'Urectum'
So answer me this.. (Score:2)
pluto is a representative planet (Score:2)
Inaccurate (Score:5, Informative)
The panel's recommendation is being reviewed by the International Astronomical Union's executive committee. In an interview last week, executive committee member Bob Williams said the definition proposed by the panel had some potential problems, and he was not at all sure if the astronomers voting in Prague this month would approve it.
"At this point, I don't feel confident enough to bet in favor of it," he said.
More than just tiny (Score:4, Informative)
Is a "planet" something that was created with the solar system, or is a "planet" simply something that has a moon? Right now, we're using the latter definition.
If you want to see another example of scientific retrenchment, check out Phylocode. For years biologists have been classifying species on a Linnaean 2D grid, inheritance and time, as if God somehow keeps all his evolutions in perfect lockstep. Phylocode, tree-based, uses the inheritance dimension only.
Re:More than just tiny (Score:5, Informative)
Pluto has a highly elliptical, out-of-plane orbit that crosses over Neptune's orbit, AND its orbit is 3/2 in phase with Neptune, suggesting that it was captured by Neptune's gravity.
Not quite, Pluto actually formed in the original Kuiper Belt [wikipedia.org], making it part of the original Solar System, not an object captured by Neptune. Its current orbit is the result of Neptune's gravity, yes, but Pluto was formed in orbit of the sun.
Is a "planet" something that was created with the solar system, or is a "planet" simply something that has a moon? Right now, we're using the latter definition.
Actually, neither Mercury nor Venus have moons, yet they're accepted as planets. The problem is not that an "incorrect" definition of planet is being used, it's that there is no clear definition of what constitutes a planet. This recommendation (the title is misleading, as no actual ruling was handed down) is merely part of a much larger debate on the definition of a planet [wikipedia.org].
Screw Pluto! (Score:2)
Absolute rubbish! (Score:2, Insightful)
Pluto Dodged A Bullet?! (Score:2)
Humans who have some ego/emotion/investment in the idea that Pluto be a planet, well that's another thing.
Re:Pluto Dodged A Bullet?! (Score:2)
Besides, consider how long Pluto had to dodge the bullet . . . with a bullet having an average speed of 1500 feet per second travelling a distance of 2.66 billion miles taking 1.40448 × 10000000000000 seconds to get there, it's not like it needed lightning reflexes or anything.
End of Science and the Modern Age (Score:5, Interesting)
As of now, the modern age is officially over and dystopic post-modern has begun.
Nope, you're wrong (Score:2)
" but strives for as much exactness as possible."
when you create a group, by definition not everyting in that group will be 100% defined by the group name.
It puts a silly arguement to bed. Thats all.
I don't really think there is a scientific term for 'planet' any how.
Do you bitch that a gas giant is called a planet?
Find your dystopia elsewhere.
Errr. Okay. (Score:3, Interesting)
"Planet" - like "hacker" has always been a very vaguely defined term and meant different things to different people. The line between "planet" and "Kuiper belt object" is as blurry as the line between two species of galapagos finch.
I've solved it in under 5 minutes (Score:2)
1. A planet is an object that orbits a star and has a mass greater than X and has a radius large enough to not be a black hole
2. A moon is an object that orbits a planet, planetoid, or astreroid
3. A planetoid is an object that orbits a star and has a mass greater than Y but less than X, and has a radius large enough to not be a
New solar system (Score:2)
The solar system consist of the Sun, the inner rocks, the asteroid belt, the gas giants, the Kuiper belt, and the Oort cloud.
This would probably give a better picture of the solar system, than the old model with a sun and nine planets.
(For historical resons, the inner rocks, the gas giants, and the first discovered object in the Kuiper belt, are called planets).
Re:End of Science and the Modern Age (Score:2)
Frankly, I think this whole argument is a bit of a distraction. It strikes me to be a lot of wasted time and energy. What type of object it is called doesn't change what the object is, unless somehow quantum mechanics applis to an object several thousands of km in diameter.
Re:End of Science and the Modern Age (Score:2)
Social acceptance is a good metric for whether a classification actually makes sense. Pluto looks, and acts very much unlike asteroids, and much more like recognized planets.
Science, however, really doesn't care about any of this. They will continue calling everything a 'body', as the boundry between planet and asteroid is really of no relevance to any of their work.
Of course, I'd like
Re:End of Science and the Modern Age (Score:3, Interesting)
I agree that Pluto does not look or act much like an asteroid, but I disagree that it looks or acts much like the recognized planets. The recognized plaents are the rocky planets plus the gas giants, and they all formed and lie in the planetary plane. Pluto looks and acts like thousands of other Kuiper objects. Kuiper objects are not formed in the same manner. Kupier objects do not lie in the planetary plane, except perh
Dodged a bullet?! (Score:2)
Doesn't qualify. (Score:5, Funny)
KeS
We should feel sorry for Pluto... (Score:2)
I'm pretty sure that (Score:2)
Historical importance... (Score:3, Insightful)
Pluto dodged a bullet? (Score:2)
The problem is not with just Pluto (Score:4, Insightful)
Re:The problem is not with just Pluto (Score:2)
1a) Orbits a star or
1b) Has a common center of orbit shared with another body that is outside both their masses, and orbits a star (this covers double planets, but not our Moon)
2) Has enough mass to maintain a roughly spherical shape (ignore the little stuff)
3) Has insufficient mass to produce heat (ignores the near-stars & stars)
4) Does not share its orbit with other bodies (excludes 'belts', regardless of object mass)
I imagine I've missed a few things. You'd need a na
Pluto, the definition of a planet, and the IAU (Score:5, Informative)
A number of years ago, the question of a definition of a planet was raised as a result of discoveries of "planets" outside of our solar system as well as a growing number of Kuiper Belt Object (KBO) discoveries in our solar system. The IAU Division of Planetary Systems Sciences technical committee wisely chose to delay a decision on a definition until a more significant body of data was obtained.
In the mean time, a well meaning but widely misunderstood suggestion from an esteemed Astronomer suggested that the planet Pluto also be given a nice round minor planet number (i.e., reserve the next multiple of 10000). His intent was to recognize the special nature of Pluto as a large member of the KBO (Kuiper Belt Object) family. He never intended to demote Pluto from planet status. However, the press took the phrase "making Pluto a minor planet" and blew the controversy way out of proportion.
An executive committee recommendation on Planet definition was formed to draft a proposal for a definition of a planet. Minutes from the IAU executive committee indicated that they favored definitions that were based on measurable physical properties over arbitrary values. For example, they signaled that they were NOT inclined to look favorably on proposals such as "limit the number of 9 planets", or proposals that set an arbitrary minimum size of a Planet.
Last January at the AAS conference, an IAU liaison announced that the IAU executive committee was scheduled to produce a report on its recommendations just prior to the IAU 26th IAU General Assembly in Prague (Aug 14 to 25, 2006). The liaison recommended that any final comments and recommendations be submitted to the exectuive committee at least a month prior to the IAU general assembly.
I was part of a group that submitted a recommendation that the definition of a Planet encompass a requirement that "it must orbit a primary fuser with sufficient mass to deform it into an spheroidal / oblate spheroidal shape". We realized that our proposal could result in redefining several bodies as planets including the large asteroid Ceres. We proposed that a new sub-class of Planets could be defined (again based on measurable physical properties) to acuminate these new dwarf planets.
We were told that a number of other groups had submitted similar of very similar proposals. I have not examined the executive committee report in detail, however it appears that IAU executive committee agrees, in principle, with such proposals.
On Tuesday 2006 August 22, 12:45-13:45 (local Prague time), in Forum Hall, executive committee recommendation on Planet definition will be presented. Based on the unanimous recommendation of the executive committee, I am hopeful of a favorable outcome form the IAU General assembly.
Canonization. (Score:2)
People arguing for and against the title, an official body deciding.
Geeze, just come up with a definition for a planet and stick with it.
Or just decide that whatever enough people call a planet is one.
You can call it a giant-dirtball-of-doom for all it matters.
Held together by gravity=yes. Chemisty = no. (Score:5, Interesting)
It's been suggested that the best way to decide what is or is not a planet is to determine if the mass is held together the force of gravity or electrostatic forces (like metal bonds).
If by gravity then it should be considered a planet. If by chemisty then it's just a hunk of rock.
This makes the most sense to me.
A proposed definition (Score:3, Interesting)
- Its primary orbit must be around a star
- It must be approximately spherical due to its own gravitational field being sufficient to make it so (the allowable eccentricity from a perfect spheroid would have to be defined)
- It is not itself a star
I see the following potential problems with this:
- It may be hard to judge shape accurately enough to tell if an object is close enough to spherical to qualify
- There may be very soft things that stay gravitationally round even when very small (what happens to a drop of mercury in space?)
- Given something such as a spheroidal asteroid smaller than Pluto, it may be difficult to distinguish if it's randomly spheroidal or spheroidal due to its own gravity.
Still, I like it better than other definitions I've seen.
Now proceed to tear it apart, add to it, etc.
Criteria (Score:3, Funny)
Because my wife always told me that it's not size, it's the technique.
Re:How Big Must a Planet be? (Score:2, Funny)
I am so sorry.
It's a familiar, if rather annoying figure (Score:2)
It has to be at least 8.2kAG
That's kilo-AlGores.
Though, like so many other cosmological units these days, it's not even a constant. Seems to be expanding (and making movies) under the pressure of hot gasses.
You hit the nail on the head (Score:2)
I could just as easily argue that saturn isn't a planet, it's a gas giant.
Re:How Big Must a Planet be? (Score:3, Interesting)
I don't think there is any distinction between planets and asteroids that is useful in Astronomy.
Besides, Pluto does not appear in Mr. Vem J Sun.
Re:How Big Must a Planet be? (Score:2)
Bingo! (Score:2)
It's funny you should mention that. ABC's season synopsis says that the upcoming episodes of Lost actually include plot elements that revolve around Iran's suppression of human rights on Pluto through the use of giant, underground, volcano-powered uber-magnets. Although it turns out that everyone's arthritis feels better, so it's sort of a wash.
Re:Heartwarming (Score:2, Flamebait)