Experts meet to decide Pluto's fate

[sun]

Pluto --the planet, may be downgraded by scientists, to something else

off of the BBC...this is part of the story,,, Astronomers to decide if Pluto is really a planet.....

"So far it looks like a stalemate," said Pavel Suchan of the IAU meeting's local organisation committee. "One half wants Pluto to remain a planet, the other half says Pluto is not worth being called a planet."

Here is the link to the entire story..http://news.bbc.co.uk/2/hi/science/nature/4789531.stm

[Romanesque]

Geez, whose idea was this? What a waste of time. =x

Experts have been arguing over Pluto since I was in gradeschool. In all that time, none of the literature ever suggested any sort of agreement. The more time passes, the more we find that falls outside older classifications; we can only expect this to continue. They'd have better spent their time trying to develop a new classification system, briefly mentioned in the article. Pluto's planetary status is a mere matter of semantics and personal opinion, by now.

--Romey

[sandwichman]

pLuTo PlAnEt P.R.E.I.D.E.

Seriously, Pluto's like the second coolest planet. If there's another planet behind it can't they just count that too :(

[tucsoncoyote]

well if you ever take a Space Trip . Don't go to Pluto, It's a Mickey Mouse Planet.

BA-Dum-DUM!

:coyote:

[MarineDweller]

Thanx for the link. Frankly to tell, ( no offense) this discussion is not needed at all. I mean come on, we still don't know, what exactly is the universe, so what's the point of discussing about planets? It could spark a lot of confusion:sad:

[EinBebop]

Lol.... when I read "decide it's fate", my first thought was, "Are we going to liberate it?" :anime:

[Temple Fugate]

Pluto is out there. Floating in space. Cold. Dead. There is no point to calling it a planet, nor is there a point in trying to remove it from official planet status. It's a frigging ROCK.

Scientists have better things to do, like finding aliens and getting us to Mars in two months instead of six. Pluto can wait until we actually have a reason to USE it for something.

[Gatomon41]

I also voice the opinion that this is a waste of time. Does it really matter if Pluto is a Planet or not?

[SilentBat18]

i third that opinion.... for all i care, pluto could just be an ice cube floating around a tall, cool glass of universe. whats important is that it still exists... um well not important to us since it doesnt really affect us all that much, but still important to the unverse i guess.

[Jave]

Unless Pluto diverts from its orbit and heads towards Earth to crash into it, I don't really care.

[mookie75]

I say let Pluto keep its planetary status. Just think of all the models of the solar system that were made for elementary school science fairs over the years...do we really want them all to be rendered inaccurate?! :D

Heck, one of the few truly interesting facts about our solar system -- the fact that Pluto isn't always the farthest planet from the sun -- would be lost if Pluto was demoted.

[Temple Fugate]

Heck, one of the few truly interesting facts about our solar system -- the fact that Pluto isn't always the farthest planet from the sun -- would be lost if Pluto was demoted.Well, it's a neat fact and all, but as of 1999, Pluto won't be the 8th planet again for another 6 or 7 generations. Try getting your kids all excited about that. :p

[Carolina Red]

If it actually orbits around the sun then we can consider UB313 a planet. It may even have civilized life for all we know.
THE NAME GAME

Many people say the sentence (called a mnemonic) "My Very Educated Mother Just Showed Us Nine Planets" as a way to remember the order of the planets.

Starting from the sun the planets are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto.

If 2003 UB313 is dubbed a planet, what new sentence will we use to remember it?

Source: NASA
And assuming that it would go under the Xena name that has been reported, it would be very difficult. And if the person who suggested the name suggested it based on television, I certainly don't think that the name would go on and get approved.

[Zach Logan]

Seeing Pluto has its own moon, Charon, I don't see why Pluto wouldn't be a planet. It may not be a gas giant, but it's still a planet

[Temple Fugate]

If 2003 UB313 is dubbed a planet, what new sentence will we use to remember it?I really hope they're not using the preservation of a mnemonic device to justify not declaring the existence of a 10th planet. At any rate, we should stop declaring new planets until we're 100% agreed that the ones we HAVE are actually planets.

BTW, many comets orbit the sun too. We don't call them planets. And what about the asteroid belt?

Are there any celestial bodies that aren't officially planets that have orbiting satellites? I think I heard about some asteroids having smaller asteroids orbiting them, but I can't remember for sure.

[Timmay]

I heard this morning.. that we may end up with 12 planets..
Ceres, Charon (Pluto's moon...), and Xena..(warrior princess!)

[Mynd Hed]

Oglethorpe: Mein Gott, arguing over such trivial matters vhen you could be genetically replicating me some snack cakes or corn-flavored chips! Vhat a bunch of NERDS!

Emory: Ooh, can they clone us a planet made out of mini-pizzas?

Oglethorpe: Ja, mini-pizzas would taste good to my pallet.

[Space Chief]

I heard this morning.. that we may end up with 12 planets..
Ceres, Charon (Pluto's moon...), and Xena..(warrior princess!)

Making Charon a planet makes sense, as I've always seen Pluto described as a "Double planet" anyway. I have no idea about Ceres, it's always been an asteroid to me.

Xena is just a temporary name-hopefully we'll have "Kobaia" as the final name.

[Gatomon41]

Hmm, looks like the commitee decided to actually expand the diffintion of a planet. At least they talked about something worthwile.

Off topic: I really hate the name Xena for any astronomical biody. Not that I hate the show, I love it, but I think it's cheap to name a planet after some pop culture reference. I say we name it Asimov instead :p

[Meson]

But Asimov isn't latin. The names of planets in our solar sysem have to have latin/roman origins (it's the law).


They say they already have 12 other candidates for planethood.

[purplehairedwonder]

They say they already have 12 other candidates for planethood.
Try coming up with a mnemonic device for that.

[Space Chief]

But Asimov isn't latin. The names of planets in our solar sysem have to have latin/roman origins (it's the law).




To hell with what the IAU says. They suck all the fun out of space anyway.

[Gatomon41]

But Asimov isn't latin. The names of planets in our solar sysem have to have latin/roman origins (it's the law).



That was a joke you know. SF fans would love to have planets named after our favorite authors.

Actually the IAU law does not state it has to be Latin in origin, since Latin is only used because it's apolitical, universal (in science), and traditional. The actual rules says you can't name anything after living people, any poltical figures after 1800's, or anyone of the major religions.

[Meson]

I was being sarcastic too...


There are reports that there might be 53 planets.

[Chrono1995]

Ceres being a planet just doesn't make sense. At all. The rest I can see easily, especially Charon.

[Gatomon41]

Ceres being a planet just doesn't make sense. At all. The rest I can see easily, especially Charon.

Actually, this is what Ceres looks like:

http://www.unknowncountry.com/img/news/092005/asteroids-1.jpg

Not really hard to see it cloud be a planet.

[Temple Fugate]

Actually, this is what Ceres looks like:

http://www.unknowncountry.com/img/news/092005/asteroids-1.jpg
Hmm. Looks a lot different from the manga.

Stop spreading slanderous lies! There are nine planets! NINE! We learned it in science so it must be true! :mad:

Unless they want to bump it up to an even count of 24. That I would be fine with.

[Meson]

What's wrong with having a dozen?

[Sr.Infierno]

Actually, this is what Ceres looks like:

http://www.unknowncountry.com/img/news/092005/asteroids-1.jpg

Not really hard to see it cloud be a planet.

'Looks like the front of Thor's costume.

[sun]

I know everyone is eager to know this important information...So, instead of starting a new thread,,just add on to this one, of immense importance..I hope everyone reads it...Evidently the crucial vote took place on 8/24/06, not 8/23...sorry.

Pluto loses status as a planet

http://newsimg.bbc.co.uk/media/images/42010000/jpg/_42010788_pluto_bbc_203.jpg Pluto's status has been contested for many years

Astronomers meeting in the Czech capital have voted to strip Pluto of its status as a planet.

Astronomers rejected a proposal that would have retained Pluto as a planet and brought three other objects into the cosmic club.
Pluto has been considered a planet since its discovery in 1930 by the American Clyde Tombaugh.
The vote effectively means the ninth planet will now be airbrushed out of school and university textbooks. (and all other media, like encyclopedias, Web Sites, Newspapers, etc.etc.etc.etc.....).




And when you lose your status like this..just think of what it means to "Pluto.".... Unable to defend itself in this time of distress....
What is a poor planet to do???







Here is the whole story
Off the BBC News....
http://news.bbc.co.uk/2/hi/in_depth/5282440.stm

[Lord Dalek]

Well... crap.

[EinBebop]

And when you lose your status like this..just think of what it means to "Pluto.".... Unable to defend itself in this time of distress....
What is a poor planet to do???Send in a UN peacekeeping force.

[Tenku]

Oh that's JUST GREAT.

Now that little jingle about the first letter of the planets is out the window. What about the pizza?! D:

[shoujoaifan]

As much as I love Pluto and all the wonderous celestrial bodies in our solar system, it basically is a celestrial body from the Kuiper Belt that is closer in orbit to the solar system than most asteroids and dwarf planets in the Kuiper Belt. Scientists NEED to classify things as they are in order to study and descibe them effectively.

But I DO have 2 problems with this:

1): The word "Planet" is like SO many terms for creatures and objects with MANY different regional names with just one scientific name.

Hell, the vernacular often confuses leopards and panthers together, while only one species is considered the "true" panther, etc. (Which species gets the official scientific name for panther and the other leopard was up to past scientists who more or less chose which to group of animals that could reproduce with each other but not the other species as "leopard", while the other was called "panther". To simplify, scientists could decide to rearrange the names of cats and dogs, the only difference would be that the two separate species would be called something else.)

Or for a simpler example, there are 2 kinds of orange fruits known in the vernacular as "pumpkins" , but they can't fertilize the other species, just the subspecies within their own species, even though they look and taste the same. Scientists then decided to call one "true" pumpkins, and the others "pumpkin-like squash". (This may not be the best example, since the pumpkin-like squash may or may not breed with normal squash, so there might be some sense behind it, but you get the general gist.)


2): They agreed that to qualify as a planet, a celestial body must be in orbit around a star while not itself being a star. It also must be large enough in mass "for its self-gravity to overcome rigid body forces so that it assumes a... nearly round shape, and has cleared the neighbourhood around its orbit."Pluto was automatically disqualified because its oblong orbit overlaps with Neptune's.

That's it.

That's IT.

That's ALL they could come up with?

C'mon guys, classify Pluto as part of the Kuiper Belt OF COURSE, as wonderous and mysterious as it is, as ANYTHING out there in the cosmos is, it basically IS a random dwarf planet from the Belt that was caught in a closer orbit than most, and its only other discernable difference between it and other Kuiper Belts bodies is that is a double darwf planet system with Charon. I still like it, but it is the truth, and nothing to be ashamed of. Dwarf planets and asteroids may not be as big or as grand as the big boys, but there still OUT THERE, these mysterious things we know so very little about, humanity having only gone to our local moon a handful of times-

-and hell, if you want to classify Pluto as a dwarf planet, then DO IT, I can support that, even though I'd rather have Pluto be a planet since A) I'm used to it being that way, and B) since it sounds better than and puts it up on a pedestal up their with the big boys of the Solar System, and C) for the sheer SIMPLICITY of keeping it as a planet, in the vernacular anyway, for historical and cultural reasons, as well as avoiding this whole debate. But even with all those reasons I would prefer it it as a planet, I can STILL get behind it as a dwarf planet to clear things up for scientific catergories, and more importantly, to keep studying as effective as possible, which needs categories in order to manage the mass amount of scientific knowledge in any and all fields-

-but THIS!?!:

They agreed that to qualify as a planet, a celestial body must be in orbit around a star while not itself being a star. It also must be large enough in mass "for its self-gravity to overcome rigid body forces so that it assumes a... nearly round shape, and has cleared the neighbourhood around its orbit."
Pluto was automatically disqualified because its oblong orbit overlaps with Neptune's. (My next rant depends if the reporter has all of the information, or if that's all the assembly has given.If that's all that's been given by the assembly, then here goes. My apology to the assembly (who won't read this anyway) if the reporter missed some key details.)




C'mon guys, just say you need Pluto described as a dwarf planet to simplify the necessary categories for describing our solar system in all its large and small wonders, don't come up with a lame reason like that.

If a planet didn't form a stable orbit that didn't "clear its neighborhood" but was dangerous for its existance if it would run into another planet, then said planet(s) would be destroyed already. Yeah, Pluto's orbit overlaps with Neptune's, but it doesn't run into it, so it's fine.

Or be HONEST (or if the assembly left it out by mistake, or the reporter forgot) and just say that the Kuiper Belts bodies have orbits similiar to Pluto, because Pluto is simliar to them, since Pluto is a body from the Kuiper Belt and thus has a similiar orbit to its brethern, except closer to the sun than the rest.

Give the WHOLE reason, explain WHY the orbit matters. (The above paragraph and the need to categorize for scientific efficiency.)




Seriously, Pluto being named a dwarf planet makes perfect sense from a scientific perspective, but the way they've gone about it, giving out only half-explained reasons, its unprofessional, and, well, its pretty damn unscientific.

(Unless the reporter only wrote down part of the explanation, or the editor shortened it up too much, or something...)

[True Noir]

This is incredibly disappointing to me. Pluto was my favorite planet.

[TheMecca]

Hundreds of scientists meet to decide if nobody really cared.
After a six-day vote, the outcome was clear: Nobody really did except nerds.

Edited so nobody would get offended: Just kidding.

[Temple Fugate]

-and hell, if you want to classify Pluto as a dwarf planet, then DO IT...I read most of your post before my brain started to hurt but I believe the article you read did not have the news that Pluto HAS been classified a dwarf. I heard it on the radio today, though they didn't give an explanation why it is so. Your argument seems very interesting, though, as you have a good point; Pluto is still an important part of our solar system, and learning about it is just as good as learning about much of anything out by the Kuiper Belt.

As for a new mnemonic device: I propose the very clear and simple "Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune." It's very easy, and you don't need to memorize an entire sentence on top of the eight full planet names.

[peacebyanymeans]

This is incredibly disappointing to me. Pluto was my favorite planet.
Really? Earth is my favorite planet, because, you know, it helps keep me from being dead.

[Conan-san]

As a Setsuna Meioh and Pluto (the robot) fan, my heart has been riped from it's chest by these logical fools.

[SAMaine]

As a Setsuna Meioh and Pluto (the robot) fan, my heart has been riped from it's chest by these logical fools.

Well, I know someone even more pissed...

Sailor Pluto: I feel insulted that the stellar body I am connected to has been demoted. I also don't want to be assoiated with Sailor Ceres or Sailor... umm... whoever the hell that is.

Sailor Ceres: I wanted to be a real Sailor Scout! T_T

Sailor "Xena": I am a warrior princess. (throws a chakram at random people)

Sailor Moon: XP There's too many of us already. You three are fired!

[Conan-san]

For starters there was already a Sailor Cres (CreCre, remember, I know SuperS sucked but...) and secondly, first person from now to make another Xena warrior princess Sailor Moon joke will get it.

[Kagetsu]

I always felt that because of it's screwy orbit it was never an original planet, but Charon Kept as one. Getting rid of it will stop all the nonsense "another planet found" everytime they see another dirty snowball. I wonder, is that like using "immenent domain" and have it condemned? :sweat:

[Artimus Gigan]

New planet memory phrase prototype by the order of offical Internet Congress Space Division:

My very Educated Mother Just Showed Us 'Nanners

However the word nanners is a slang term for bananna, the other debated replacements are the words "Nothing", "Nutmeg", "Norsemen", and "Nga'chug"

Supposedly it's going to take until 2010 until all the sciencebooks in the schools in the the US are replaced with this new order of planets that dismiss pluto. I really don't think that this is going to hold and they're just going to say the heck with it, and revert it back to the traidtional way.

[Jave]

**Begins countdown until the Plutonians invade Earth**

"How DARE you remove us from consideration!"

[Rocketboy]

I thought that EXACT same thing.

[SAMaine]

For starters there was already a Sailor Cres (CreCre, remember, I know SuperS sucked but...) and secondly, first person from now to make another Xena warrior princess Sailor Moon joke will get it.

Of course, I know there was a Sailor Ceres. She's part of Chibimoon's Inner Scouts.

"Nga'chug"

Is... Is that a Klingon word?!

Also the mnemoric should be "My Very Educated Master Just Showed Us Ninjitsu"

[True Noir]

Really? Earth is my favorite planet, because, you know, it helps keep me from being dead.

Earth? Been there. Done that.

[peacebyanymeans]

Earth? Been there. Done that.

Fine, go to Pluto. But don't coming crying to me when you died from lack of atmosphere and heat. :mad:

[tucsoncoyote]

Well it's official now.. Pluto is a dead issue... Oh and I have a guest speaker here, and here's what he has to say...:


http://www.thijssenonline.com/hercules/hades02.gif
Hades (aka Pluto):
You know Bubula,
I AM NOT PLEASED ABOUT THIS!!!!!
I mean come on, I should have a Planet named after me!
After all I'm the god of the Underworld for
Zeus' sake!
I hope my big Brother (Zeus)
Smites all those Astronomers!
What Chutzpah they have,
Taking away MY Planet!
The Planet they named after me...
ME!


See this is what happens when you peeve off the gods.



And thank you for that Commentary, Lord of the Underworld, Now back to our regularly Scheduled programming....

:coyote:

[SAMaine]

Wait a minute, the defination of a planet requires that the planet "clear the neighborhood" of any other stellar bodies. The prime example for Pluto's demotion is that it didn't clear Neptune out, but what about Neptune? It didn't clear out Pluto. Hell, any planet with a moon hasn't cleared its orbit of bodies. (That's Earth, Mars, Jupiter, Saturn, Uranus, and Neptune for you) I mean hell, Saturn's lighter than water and has it's own personal Kuiper belt. We need a SIZE defination for a planet.

[Duke]

Supposedly it's going to take until 2010 until all the sciencebooks in the schools in the the US are replaced with this new order of planets that dismiss pluto. I really don't think that this is going to hold and they're just going to say the heck with it, and revert it back to the traidtional way.
Now watch. In 2011 they'll call it a planet again, thus forcing the textbooks to be changed once again and for people to whap the nerds for not being decisive.
Is... Is that a Klingon word?!
I think it's the word Apache Chief says when he gets taller.

[William C. Maune]

Wait a minute, the defination of a planet requires that the planet "clear the neighborhood" of any other stellar bodies. The prime example for Pluto's demotion is that it didn't clear Neptune out, but what about Neptune? It didn't clear out Pluto. Hell, any planet with a moon hasn't cleared its orbit of bodies. (That's Earth, Mars, Jupiter, Saturn, Uranus, and Neptune for you) I mean hell, Saturn's lighter than water and has it's own personal Kuiper belt. We need a SIZE defination for a planet.

Size definitions are arbitrary, I think the new definition works a lot better. "Clear the neighborhood" is referring to the planet's orbit of the sun. Moons orbit the planet, not the sun and thus they are clearly different. As for Neptune, it is by far the dominant planet over Pluto, and unlike Pluto, it has a circular orbit. If Pluto and Neptune ever came near each other as their paths crossed, it would be Pluto that would be thrown out of whack, or even captured.

Whereas picking a size is arbitrary, the new definition relies on specific questions: Does it orbit a star? Is the orbit circular? And, Does it clear the neighborhood? While the 8 planets fit though, Pluto doesn't since it has an elliptical orbit and it wouldn't "clear the neighborhood" if it and Neptune met. Pluto has never been like the others and as we have learned more about the Kupier Belt region, it seems to fit there a lot better. This definition fairly defines things.

[tucsoncoyote]

Wait a minute, the defination of a planet requires that the planet "clear the neighborhood" of any other stellar bodies. The prime example for Pluto's demotion is that it didn't clear Neptune out, but what about Neptune? It didn't clear out Pluto. Hell, any planet with a moon hasn't cleared its orbit of bodies. (That's Earth, Mars, Jupiter, Saturn, Uranus, and Neptune for you) I mean hell, Saturn's lighter than water and has it's own personal Kuiper belt. We need a SIZE defination for a planet.

I think you make a concise point here, SAMaine, and in fact I have always thought that a planet should be defined by at least a size. If It were me any body over 1/4 earth diameter (3,189 km) then it would be a planet. in fact every planet save for Pluto does qualify as a planet if we use the 1/4 earth size ratio (Pluto has a diameter of less then this, but still would be considered not a planet

I think unless the geeks and the nerds out there have a better option, Pluto just doesn't make the cut. (or the size) to really be called a planet.

[SirLemming]

If I ever go to a wrestling event again, I will definitely have a "PLUTO IS A PLANET" sign.


I'm also looking forward to Conan O'Brien's "Cheer Up, Pluto!" segment. Or perhaps it'll be, "Pluto isn't a planet? No, no, that isn't true! THERE'S NO REASON TO LIVE! WHERE'S MY KAYAK?"

[Gatomon41]

Yeah, I'm not happy about this either. Expanding the diffintion of a planet would have been better. Oh well, Pluto is probably going to be kept on Solar System models anyway. You can't beat down old traditions.

[Temple Fugate]

Is... Is that a Klingon word?!Yes. Something relating to sex.

I think it's the word Apache Chief says when he gets taller.LOL

Is calling Pluto a planet really that much of a "tradition?" Sure, most of us weren't born yet when Pluto was discovered, but when I think "tradition," I think centuries-old holidays and the like, not something that was only established 50 years ago. By the way, considering the Earth the center of the universe was also a "tradition" at one point. Inevitably this declaration of dwarf planet Pluto will mean absolutely nothing in the long run, since Pluto is still out there and doing exactly what it's been doing for millions of years. A rose by any other name, and all that.

[Kagetsu]

I mean hell, Saturn's lighter than water Who on godsgreenearth told you that? Saturn is a gas giant like Jupiter and therefore extremely dense at it's core.

[One Radical Dude]

This has got to be the dumbest thing I've ever read -- Pluto, no longer a planet? Pluto = Planet 4-eva!!

[Romanesque]

Size definitions are arbitrary, I think the new definition works a lot better.Ultimately, all these planetary definitions are arbitrary. Our system's planets are clumpings of different size and composition, different for no other reason than that's the way they are. In some other system, things clumped differently. There's no special reason to call one thing a planet, one thing a dwarf planet, or another thing an asteroid, other than the fact that we have a mindset that demands we classify things to understand them. The question is, what classification is most convenient for us, here and now?

Pluto's reclassification doesn't bother me, though I'm not fond of the term "dwarf planet"... which just screams, "hey, I'm a small planet!" Gee, that's brilliant. It was sooo worth the trouble. Ehh, whatever. They'll just re-reclassify it in another decade or so.

Moons orbit the planet, not the sun and thus they are clearly different.Not always. ;)

In general, we like to think of little things orbiting bigger things, but it's not always so easy to tell. The frame of reference you choose matters.

Does Charon orbit Pluto? Do they orbit each other? Or should we say they mutually orbit the sun with a shared wobble? They move the way they move, how we describe it is a matter of convenience.

Consider trojan satellites. In one frame of reference, they orbit the sun in a number of fancy and not so fancy ways. In another frame of reference, they orbit a Lagrange point shared by the sun and planet. The description is arbitrary.

Back to Charon and Pluto, they're very close in relative size. However, the Earth and our Moon are also relatively close in size as far as planets and moons go. Another odd fact is that our Moon could be said to orbit the sun in that its "solar orbit" is convex... a slightly perturbed circle that never loops back on itself. The barycenter, around which the Earth and Moon orbit each other, may be below Earth's surface, but it's actually almost 3x closer to the surface than it is to the planet's center. Heck, the barycenter is even continuing to move outward.

'Course, it'd be silly for the Moon not to be a moon... right?

Romey
--"This has been another... Useless Fact" :p

[William C. Maune]

Ultimately, all these planetary definitions are arbitrary. Our system's planets are clumpings of different size and composition, different for no other reason than that's the way they are. In some other system, things clumped differently. There's no special reason to call one thing a planet, one thing a dwarf planet, or another thing an asteroid, other than the fact that we have a mindset that demands we classify things to understand them. The question is, what classification is most convenient for us, here and now?

Ultimately then, all things are arbitrary. Ultimately though, picking specific characteristics that an object either does or doesn't have is a lot less arbitrary than picking a random measurement.

[tucsoncoyote]

Who on godsgreenearth told you that? Saturn is a gas giant like Jupiter and therefore extremely dense at it's core.

Actually SAMaine is correct. the overall density of Saturn (as an average (even with it's liquid hydrogen core is 0.94 compared to earths average density of 5.5, which thus makes the planet float in water (1.0)....

after all we're talking average density of a planet here, not just specific parts of a planet.

:coyote:

[Kagetsu]

No,,, even though I wouldn't understand it, you'd have to show me the math.

Gravity is directly related to mass/density (samething). Just look at the number and size of moons that are affected by Saturns gravity well. It's hardly a nebula (expanding gas from an exploded star)

[Romanesque]

Ultimately then, all things are arbitrary.You say that as if it were a bad thing. I think the arbitrary aspect is rather important to remember when the only thing at stake is a definition. One of little social consequence, even if it's amusing to argue about.

Ultimately though, picking specific characteristics that an object either does or doesn't have is a lot less arbitrary than picking a random measurement.I find that distinction entirely arbitrary! Well, not really, but I just wanted to say it. Like it or not, random measurements happen. Personally, I don't like it, either. You might think I'm being coy, but I'm not. Not at this very moment.

Size isn't all that arbitrary, in the sense you speak of. Depending on a planet's composition, size (mass, rather) will determine whether or not it assumes a spherical shape, among other things.

You're not talking about size in that sense, of course. You mean mean size and size alone as a qualifier of whether or not an object is called a planet. All I'm saying (I think) is that once you move beyond that measure, your choice of other measures is still arbitrary.

Darnit, now I've gone and confused myself. For now.

Gravity is directly related to mass/density (samething).Not at all the same thing, actually. Gravity is directly related to mass, yes, but not density. To relate mass to (average) density, you have to consider volume. Two planets with the same mass but different volume will have the same gravitational pull.

--Romey

[William C. Maune]

You say that as if it were a bad thing. I think the arbitrary aspect is rather important to remember when the only thing at stake is a definition. One of little social consequence, even if it's amusing to argue about.

It's not necessarily a bad thing. Heck, in the grand scheme of things it's nice to think about in sort of a "don't sweat the small stuff" sort of sense. At the same time, declaring everything to be arbitrary also shouldn't be used as an excuse to say nothing matters. All of science is ultimately arbitrary, but all of science is also ultimately important. The old definition of "well, it's a planet" worked really well for thousands of years. However, as our knowledge base grows, it becomes necessary to revisit our definitions and classifications. Science is based on definitions and classifications and I like to see it done right.

Size isn't all that arbitrary, in the sense you speak of. Depending on a planet's composition, size (mass, rather) will determine whether or not it assumes a spherical shape, among other things.

Actually, if that type of "size" were used as a definition, I wouldn't have a problem with it either. When classifying things it makes more sense to say "we chose to draw the line at this size because this size determines whether or not the object... (assumes a spherical shape, or etc.)" as opposed to "we chose to draw the line at this size because we like 250 units better than 500 units."

[SAMaine]

Size definitions are arbitrary, I think the new definition works a lot better. "Clear the neighborhood" is referring to the planet's orbit of the sun. Moons orbit the planet, not the sun and thus they are clearly different. As for Neptune, it is by far the dominant planet over Pluto, and unlike Pluto, it has a circular orbit. If Pluto and Neptune ever came near each other as their paths crossed, it would be Pluto that would be thrown out of whack, or even captured.
Whereas picking a size is arbitrary, the new definition relies on specific questions: Does it orbit a star? Is the orbit circular? And, Does it clear the neighborhood? While the 8 planets fit though, Pluto doesn't since it has an elliptical orbit and it wouldn't "clear the neighborhood" if it and Neptune met. Pluto has never been like the others and as we have learned more about the Kupier Belt region, it seems to fit there a lot better. This definition fairly defines things.
Actually if Pluto and Neptune ever met in orbit, Pluto would crash into Neptune and could possibly shatter Neptune, Pluto and Charon into various pieces, the biggest being New Neptune. We are talking two comets only slightly less the size of Mercury. I'd fear for my life if I saw Pluto headed towards MY planet!
I think you make a concise point here, SAMaine, and in fact I have always thought that a planet should be defined by at least a size. If It were me any body over 1/4 earth diameter (3,189 km) then it would be a planet. in fact every planet save for Pluto does qualify as a planet if we use the 1/4 earth size ratio (Pluto has a diameter of less then this, but still would be considered not a planet
I think unless the geeks and the nerds out there have a better option, Pluto just doesn't make the cut. (or the size) to really be called a planet.
You should add a modifier to that... any body over 1/4 earth diameter (3,189 km) that orbits a sun should be considered a planet. I mean Jupiter's moons (Ganymede, Callisto and Io), Saturn's moon (Titan), and Earth's Moon are all large than the one-fourth diameter.
Who on godsgreenearth told you that? Saturn is a gas giant like Jupiter and therefore extremely dense at it's core.
Well, I meant it floats on an equal amount of water.
Personally, we should call the 8 big ones "The Major Planets," the 3 dwarf ones "The Minor Planets" and the rest of the junk that isn't a star "Small Solar System Bodies"

[Romanesque]

It's not necessarily a bad thing. Heck, in the grand scheme of things it's nice to think about in sort of a "don't sweat the small stuff" sort of sense. At the same time, declaring everything to be arbitrary also shouldn't be used as an excuse to say nothing matters.Thankfully for this thread, I'm not using it as an excuse to say nothing matters. :sweat:

The old definition of "well, it's a planet" worked really well for thousands of years. However, as our knowledge base grows, it becomes necessary to revisit our definitions and classifications.Funny you should mention that... since the definition of "planet" that we've been working with for the last few centuries is far far removed from the original. That too was caused by our growing knowledge base. Unfortunately for the definitions, our knowledge is likely to outpace this newest definition pretty quickly.

...and I still don't like the term "dwarf planet". :p
Somewhere, there are dwarves who will be offended!

Science is based on definitions and classifications and I like to see it done right.Darnit, we disagree on our definitions of "Science" and "done right", too. ;-)

--Romey

[William C. Maune]

Darnit, we disagree on our definitions of "Science" and "done right", too. ;-)

--Romey

Maybe, maybe not. How would you define the two of those?

[Romanesque]

Maybe, maybe not. How would you define the two of those?Personally, I'd define them in another thread. A thread I don't care to start at the moment.

--Romey

[purplehairedwonder]

While I can understand people wanting to revisit the definitions as our base understanding of things change, I still don't like the idea of "demoting" Pluto. Though, I guess I can see the other side (especially whoever brought up the point that everyone used to have the geocentric view of the universe and that had to change... but I don't think this is quite the same thing). But I just don't like it.

[Mynd Hed]

I think it's the word Apache Chief says when he gets taller.

That would be "Inuk-chuk."

[Tenku]

Well, we got a new *dwarf* planet (http://news.yahoo.com/s/ap/20060914/ap_on_sc/dwarf_planet).

Eris and the moon, Dysnomia.

[Gatomon41]

Well, we got a new *dwarf* planet (http://news.yahoo.com/s/ap/20060914/ap_on_sc/dwarf_planet).

Eris and the moon, Dysnomia.

Yay! They didn't name it Xena after all! :anime: Victory!

[Zinal]

Oh well, I guess we have 8 Planets now.

[Space Chief]

Yay! They didn't name it Xena after all! :anime: Victory!
But then again, they didn't name it Kobaia.
Stupid boring mythology...

[Dr.Pepper]

Pluto not being a planet is something that will take me a while to get use to.

[Gatomon41]

But then again, they didn't name it Kobaia.
Stupid boring mythology...

Do you perfer we name it Cthulhu instead?


Oh, PLUTO WILL RISE AGAIN!

[Temple Fugate]

I like to think we have eleven planets. Eight are full-fledged and three are dwarf.

If you had one full brother and one half-brother, do you just say you have two brothers? It's kind of like that.