NationStates Jolt Archive

So the IAU have voted that Pluto has no longer a planet. Their definition is:

A planet as officially defined by the International Astronomical Union is a celestial body that is (a) in orbit around a star or stellar remnants, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, (c) is not massive enough to initiate thermonuclear fusion of deuterium in its core, and (d) has cleared the neighbourhood around its orbit.(Source: IAU website).

I can see some problems with this:
1: Since Pluto is in Neptune's "neighbourhood" shouldn't that be downgraded too?
2: They are defining planets by their position as opposed to their size, which I thought would be more important. Pluto would be a planet if it didn't cross Neptune's orbit!
I feel that their definition isn't good enough, though I'm no expert. Any views?

Y'see, I think this is all bullshit, because, c'mon, a bunch of nerds just told us Pluto isn't a planet. Are you gonna let a bunch of nerds tell you what to think, what is and isn't right? Fuck it, Pluto is a planet, and as of now, Ceres is too.

Damn nerds.

Y'see, I think this is all bullshit, because, c'mon, a bunch of nerds just told us Pluto isn't a planet. Are you gonna let a bunch of nerds tell you what to think, what is and isn't right? Fuck it, Pluto is a planet, and as of now, Ceres is too.

Damn nerds.

Thanks for your opinion, but I was hoping for a bit more discussion than "screw nerds".

Thanks for your opinion, but I was hoping for a bit more discussion than "screw nerds".
What? It's a valid opinion.

It is a bit of a stupid definition, seeing as Earth, Mars, Jupiter and Neptune have also not fully cleared their orbital zones. But then Pluto was always pushing it in wanting to be a planet, so it's 'demotion' was probably inevitable.

What? It's a valid opinion.

If only everything in life was defineable this easy. :D

Pluto is a planet to me no matter what anyone says and thats whats important

It seems that the concept of a cultural planet is coming into play here.A "We've always been told it was a planet so let's keep it that way" kind of thing. Here's my suggestion (Feel free to poke holes in it):
A planet is a celestial body that is (a) in orbit around a star or stellar remnants, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, (c) is not massive enough to initiate thermonuclear fusion of deuterium in its core, (d) has a volume greater or equal to 6×10^10 km³ and (e) have the barycentres of any nearby objects within its surface.

It seems that the concept of a cultural planet is coming into play here.A "We've always been told it was a planet so let's keep it that way" kind of thing. Here's my suggestion (Feel free to poke holes in it):
A planet is a celestial body that is (a) in orbit around a star or stellar remnants, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, (c) is not massive enough to initiate thermonuclear fusion of deuterium in its core, (d) has a volume greater or equal to 6×10^10 km³ and (e) have the barycentres of any nearby objects within its surface.
Can I get the last two in layman's terms please?

So the IAU have voted that Pluto has no longer a planet. Their definition is:

A planet as officially defined by the International Astronomical Union is a celestial body that is (a) in orbit around a star or stellar remnants, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, (c) is not massive enough to initiate thermonuclear fusion of deuterium in its core, and (d) has cleared the neighbourhood around its orbit.(Source: IAU website).

I can see some problems with this:
1: Since Pluto is in Neptune's "neighbourhood" shouldn't that be downgraded too?
2: They are defining planets by their position as opposed to their size, which I thought would be more important. Pluto would be a planet if it didn't cross Neptune's orbit!
I feel that their definition isn't good enough, though I'm no expert. Any views?
1. Pluto is not in Neptune's orbit, it crosses it twice per orbit, I think.
2. Position is better definition than size.

I am strongly for the current definition and am thankful it is finally taken care of. Pluto should never have been made a planet. People need to grow up and accept it.

2. Position is better definition than size.


What's your reasoning behind this?

Pluto should never have been made a planet. People need to grow up and accept it.

why does it really matter?

1. Pluto is not in Neptune's orbit, it crosses it twice per orbit, I think.


Sorry, this was due to my poor phrasing. I meant that it crosses Neptune's orbit.

why does it really matter?
It matters to NASA. They've just sent a multi million dollar probe to visit the only remaining unexplored 'planet', only for it to be downsized enroute. :p

Can I get the last two in layman's terms please?

(d) It's the same size or bigger than Mercury (approx.)
(e) If there is more than one body, one is orbiting the other (like the Moon and Earth), they are not orbiting each other (like Pluto and Charon).

It matters to NASA. They've just sent a multi million dollar probe to visit the only remaining unexplored 'planet', only for it to be downsized enroute. :p

Almost as good as the probe they sent to mars and some of the programmers were working in metric and some in imperial.

What? It's a valid opinion.

It can be valid, in that it contains no contradictions, and still be stupid and fail to advance the conversation.

And to specifically respond: We "nerds" are the only ones who can really say anything about it, since it is we who discover planets for those, such as you, who are unable to do so themselves, and since it we, not you, who actually understand the science that makes a celestial object a planet, or not as the case may be.

Attempt not to baselessly insult the people without whom you could not have a conversation about Pluto, or indeed about any astronomy not involving the geocentric model.

It can be valid, in that it contains no contradictions, and still be stupid and fail to advance the conversation.

And to specifically respond: We "nerds" are the only ones who can really say anything about it, since it is we who discover planets for those, such as you, who are unable to do so themselves, and since it we, not you, who actually understand the science that makes a celestial object a planet, or not as the case may be.

Attempt not to baselessly insult the people without whom you could not have a conversation about Pluto, or indeed about any astronomy not involving the geocentric model.
:rolleyes:
Shut up and learn to take a joke, you whiny nerd.

(d) It's the same size or bigger than Mercury (approx.)
(e) If there is more than one body, one is orbiting the other (like the Moon and Earth), they are not orbiting each other (like Pluto and Charon).
Thank you. So, basically, Pluto fits all the criteria but those two? ...It's round, it orbits a star, it doesn't reach critical mass...

Thank you. So, basically, Pluto fits all the criteria but those two? ...It's round, it orbits a star, it doesn't reach critical mass...

Yep. So in my opinion it still isn't a planet. Pluto and Charon are "double dwarf planets".:D

Yep. So in my opinion it still isn't a planet. Pluto and Charon are "double dwarf planets".:D
Ah. Well, from a scientific standpoint, its not a planet... but it was still named after the best god in the Greco-Roman pantheon. It's cool enough to hang with the planets. :cool:

:rolleyes:
Shut up and learn to take a joke, you whiny nerd.

I'm sorry for going off on you, but you have no idea how many times that exact sentiment, applied to myself, my friends, or my arguments or opinions, has come up in my memory. Redneck anti-intellectual sentiment just really pisses me off, joking or whatever.

I'm sorry for going off on you, but you have no idea how many times that exact sentiment, applied to myself, my friends, or my arguments or opinions, has come up in my memory. Redneck anti-intellectual sentiment just really pisses me off, joking or whatever.
*shrug* I'm not a redneck or an anti-intellectual. In fact, I used to be a nerd, which middle school beat out of me. :cool:

I don't like nerds, but I don't define them as smart people, I define them as people without social skills. Or I use the term to poke fun at smart people. :D

Ah. Well, from a scientific standpoint, its not a planet... but it was still named after the best god in the Greco-Roman pantheon. It's cool enough to hang with the planets. :cool:
Too bad it's too short:
http://sorrypluto.ytmnd.com/

Too bad it's too short:
http://sorrypluto.ytmnd.com/
It's like our midget friend. We find it funny, strange, and endearing all at once.

I, for one, am genuinely sad about Pluto being demoted. To me, Pluto represented the last true unknown within our reach.

I am especially sad about the vote being hijacked.

Article...from the Beeb. (http://news.bbc.co.uk/2/hi/science/nature/5283956.stm)

The new planet definition that relegates Pluto to "dwarf planet" status is drawing intense criticism from astronomers. It appears likely that the definition will not be widely adopted by astronomers for everyday use, even though it is the International Astronomical Union's (IAU) official position.

On Thursday, astronomers at the IAU meeting in Prague approved a resolution that says the solar system has only eight planets, with Pluto excluded. Pluto is considered a "dwarf planet" instead.

But the new definition has provoked a backlash. Alan Stern, who heads NASA's New Horizons mission to Pluto and works at the Southwest Research Institute in Boulder, Colorado, US, says the new definition is "awful".

"The definition introduced is fundamentally flawed," he told New Scientist. "As a scientist, I'm embarrassed."

Four planets
He says only four of the eight objects mentioned in the IAU definition actually meet the definition's criteria – and Earth, Mars, Jupiter and Neptune do not.

The definition stipulates that to be a planet, an object must have cleared the neighbourhood around its orbit. But Earth's orbital neighbourhood is filled with thousands of near-Earth asteroids, Stern says.

And Mars, Jupiter and Neptune have so-called "Trojan" asteroids sharing their orbits. "This is a half-baked criterion for planethood," he says.

He says the new definition was pushed by people who are unhappy with having large numbers of planets – an earlier proposal would have potentially allowed hundreds of new planets into the fold.

"It's just people that say things like, 'School kids will have to memorise too many names.' Do we limit the number of stars because children have to think of too many names? Or rivers on the Earth? It's just crazy," Stern told New Scientist.

Minority report
Stern is also critical of the fact that only astronomers present for the vote, which occurred at the end of the two-week meeting, were allowed to have their say on the matter. No email voting was allowed for the decision – it was made by a show of hands – and that meant that less than 5% of the nearly 9000 IAU members actually voted.

"You're going to see a real backlash in the coming weeks," he says. "I know there is a petition among planetary scientists that's getting a lot of support."

In any case, he says, astronomers are not obligated to use the new definition, since the IAU does not have the power to enforce it. "I don't think it's going to be very widely followed," he says.

David Weintraub, author of the upcoming book Is Pluto a Planet? and a researcher at Vanderbilt University in Nashville, Tennessee, US, says he thinks Pluto is still a planet – even under the new definition.

Grammar issue
"As best I can tell, 'dwarf' is an adjective and 'planet' is a noun," he told New Scientist. "I think the IAU thinks they defined Pluto to not be a planet. But they in fact have defined Pluto to be a planet – a particular kind of planet."

Astronomers who proposed the new definition respond that the term "dwarf planet" is meant to be thought of as a single concept. And others point out that "minor planets" – asteroids and other small bodies – are not considered planets.

But he agrees with Stern that the stipulation that a planet clears out its neighbourhood is flawed. A better definition would say a planet is an object that orbits a star and is large enough to be spherical, but is not large enough to be a brown dwarf – a "failed" star with between about 13 and 75 times the mass of Jupiter – or a star, he says.

'This is crazy'
"Everyone agrees on those criteria," he says. "The question is, can we agree on additional criteria to refine the definition further? I think the answer is no."

"Everybody who has communicated with me is saying, 'This is crazy and we don't agree with it,'" he adds. "I'm not convinced that the folks who were at the meeting represented well the larger community."

But not everyone is unhappy with the decision. Richard Conn Henry of Johns Hopkins University in Baltimore, Maryland, US, says he is pleased with the outcome. "As far as I'm concerned, the right decision was made," he told New Scientist. "I know a planet when I see it and there are eight of them."

He says it makes no sense to call Pluto a planet because it is just one of huge numbers of objects in the Kuiper Belt beyond Neptune.

the new definition means there are only 4 planets in our solar system, no one will follow it and the IAU cant make ppl follow it.

This topic is closed, if you give the correct info it wouldnt of gone so far