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Dwarf Planets Accumulate In Outer Solar System

kdawson posted more than 4 years ago | from the potato-radius dept.

Space 93

An anonymous reader tips a piece in Australian Geographic indicating that Pluto may be in for another demotion, as researchers work to define dwarf planets more exactly. "[Australian researchers] now argue that the radius which defines a dwarf planet should instead be from 200–300 km, depending on whether the object is made of ice or rock. They base their smaller radius on the limit at which objects naturally form a spherical rather than potato-like shape because of 'self-gravity.' Icy objects less than 200 km (or rocky objects less than 300 km) across are likely to be potato shapes, while objects larger than this are spherical. ... They call this limit the 'potato radius' ... [One researcher is quoted] 'I have no problem with there being hundreds of dwarf planets eventually.'"

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93 comments

Proper nomenclature (5, Funny)

BadAnalogyGuy (945258) | more than 4 years ago | (#31789180)

The preferred term is size-challenged planets.

I GOT A GREASED UP DWARF PLANET SHOVED UP MY ASS (-1, Troll)

Anonymous Coward | more than 4 years ago | (#31789348)

GO LINUX! [goatse.fr]

Re:I GOT A GREASED UP DWARF PLANET SHOVED UP MY AS (0)

Anonymous Coward | more than 4 years ago | (#31789438)

That's what your mom's butt looked like after I put my Plutoid in it.

Re:I GOT A GREASED UP DWARF PLANET SHOVED UP MY AS (0)

Anonymous Coward | more than 4 years ago | (#31790004)

Your Plutoid? Is it like a penis only smaller?

Re:I GOT A GREASED UP DWARF PLANET SHOVED UP MY AS (0)

Anonymous Coward | more than 4 years ago | (#31790164)

No, he just ment to say he likes gays because he puts it in the butt and has buttfixation.

I wished he'd take up on auto-batmasphyxia, auto-asphyxiation while wearing a batman outfit.

Re:I GOT A GREASED UP DWARF PLANET SHOVED UP MY AS (0)

Anonymous Coward | more than 4 years ago | (#31792340)

Can I borrow your batman suit when you're done choking yourself out?

Re:Proper nomenclature (1)

Waffle Iron (339739) | more than 4 years ago | (#31789462)

The preferred term is size-challenged planets.

That projects too much negativity. The new recommended term which looks to a more positive future is: "Presently Accreting Planets".

Re:Proper nomenclature (1)

John Hasler (414242) | more than 4 years ago | (#31789738)

> The new recommended term which looks to a more positive future is:
> "Presently Accreting Planets".

That's not so positive if you live on one.

Re:Proper nomenclature (1)

saider (177166) | more than 4 years ago | (#31790122)

All planets are presently accreting. Go outside tonight and look for accretion events (AKA shooting stars).

Re:Proper nomenclature (1)

jonadab (583620) | more than 4 years ago | (#31796202)

Why not just officially label them "developing planets" and have done? Then people who don't care about being politically correct can go right on calling them "third world planets".

Re:Proper nomenclature (0)

Anonymous Coward | more than 4 years ago | (#31789568)

The preferred term is size-challenged planets.

Wrong. I believe it's "little-person planet."

Re:Proper nomenclature (1)

Heed00 (1473203) | more than 4 years ago | (#31790662)

Radially challenged.

Re:Proper nomenclature (0)

Anonymous Coward | more than 4 years ago | (#31793252)

they might be small for planets but if we launch enough syrup at one of the ice ones we could make a giant slushy, we could have a hollowed out rocket for the straw. the real question is would it truely count as a slushy without a giant waxed paper cup?

Re:Proper nomenclature (1)

blackbear (587044) | more than 4 years ago | (#31794208)

Pluto may be a dwarf planet, but it has a LONG orbit.

Let it go (1)

sznupi (719324) | more than 4 years ago | (#31789204)

Planets were in the past, for example, emissaries of the gods. The Moon was considered a quite distinct body. Epicycles and heavenly sphere have also went away.

Re:Let it go (3, Interesting)

john83 (923470) | more than 4 years ago | (#31789346)

Actually, our own moon is a planet according to their definition - it's over 3000 km across. As I understand it, it's not currently classified as one because the earth-moon system's centre of gravity is inside the earth.

Re:Let it go (2, Informative)

Theuberelite (1786666) | more than 4 years ago | (#31789580)

A dwarf planet must "not be a satellite of another planet" so our moon does not count as a dwarf planet according to the IAU.

Re:Let it go (1)

Teancum (67324) | more than 4 years ago | (#31791816)

So what is the point of the heliocentric definition of a planet?

I don't mind if Io, Europa, Ganymede, Callisto, Titan, and other similar bodies are all classified as "dwarf planets". It would be an excellent definition.

Heck, I think Mercury ought to be classified as perhaps a "dwarf planet" and that a line be drawn between planets that are merely large enough to become spherical and those which can hold an atmosphere. Another category ought to also include those planets for which a majority of the mass is gaseous (aka the "gas giants"). BTW, I would put Titan in the same classification as the Earth, Venus, and Mars under this non-heliocentric classification.

This is only going to become much more of an issue when the exo-planets are studied in detail, and we start to discover smaller non-stellar bodies that don't even orbit stars of any kind except the center of the galaxy. I'd even be willing to wager that the number of these objects that don't even orbit stars that are "planetary sized" outnumber those objects which orbit stars under a reasonable definition of what constitutes a planet.

The current IAU definition really is a poor solution, particularly if they keep tweaking the definition in all sorts of weird ways.

Re:Let it go (1)

interiot (50685) | more than 4 years ago | (#31793668)

What happens in Titan's neighborhood is determined mainly by the gravity of Saturn. Everything that happens now (its orbit, what impacts it) is dominated by Saturn's gravity, and everything about Titan's past (formation out of the dust disc that circled the early Saturn) was dominated by Saturn's gravity.

It's not heliocentrism, it's a recognition that gravitational relationships are hierarchical. That's true from moons to plants to stars to galaxies to clusters.

Going in the other direction, there's debate about whether rogue planets [wikipedia.org] (planet-like bodies that orbit a galaxy but aren't attached to any star) can be properly called a "planet".

Re:Let it go (1)

Teancum (67324) | more than 4 years ago | (#31803484)

Although there certainly deserves to be a classification note of some kind that identifies those objects which are dominated gravitationally by some other body, I don't think it really is well deserving to be so hard-nosed about dismissing Titan as a planet here either. With the sole exception that it happens to be dominated by Saturn rather than the Sun, it really does fit every other conceivable definition of a planet, and certainly would be called one if it were merely orbiting the Sun.

I do envision that a problem is soon going to develop going the other direction too, in terms of the very small bodies of the Solar System. We have asteroids as a very loose definition of being something roughly inside the orbit of Jupiter that is not really planet sized. A slightly better definition is something smaller than a dwarf planet. Just how small of an object can something be to still be classified as an asteroid? Something the size of a city, a house, a sofa, or a fist (to give some rough scale equivalents)? Does a grain of sand count as something which should be named and given a classification number in the IAU minor planet catalog? We are very nearly at that point of absurdity right now.

I could argue that perhaps a legal definition might even be eventually adopted, where something formally classified as an asteroid might have some sort of "protected" status but smaller object can be manipulated and refined into manufactured good. When people start to get serious about mining asteroids, it will become a big deal. The date that will start to happen is sooner than you think.

BTW, stars are classified based strictly on its spectral type and raw physical characteristics, not by its particular relationship with other objects in the universe. Why should planets be different?

Re:Let it go (1)

budgenator (254554) | more than 4 years ago | (#31789604)

The IAU’s definition decrees that a dwarf planet must orbit the Sun, must not be a satellite of another planet, must not have cleared its orbit of debris (like larger planets do) and it must be of sufficient mass to assume a nearly round shape. They also state that dwarf planets should be of a certain brightness, which is only possible with objects with a radius of more than 420 km.

The moon orbits the Earth, not the sun.

Re:Let it go (1)

nottheusualsuspect (1681134) | more than 4 years ago | (#31789974)

As I understand it, it's not currently classified as one because the earth-moon system's centre of gravity is inside the earth.

The moon orbits the Earth, not the sun.

Isn't that what he said?

No, seriously, doesn't

"the earth-moon system's centre of gravity is inside the earth"

mean the same as

"The moon orbits the Earth"

?

Or do I just read it like that as I already knew it, therefore I automatically draw a conclusion?

Re:Let it go (0)

Anonymous Coward | more than 4 years ago | (#31790128)

It's hard to tell what the hell he's saying since he contradicted himself. First he says that our moon is a planet according to the IAU definition, then in the very next sentence he says it's not.

Re:Let it go (0)

Anonymous Coward | more than 4 years ago | (#31790530)

Actually, he didn't contradict himself, though it probably looked that way due to pronoun usage and Slashdot's RTFA percentages. In his comment, "their" referred to the article's authors, NOT IAU.

Clarified:
The Moon would be a (dwarf) planet by (TFA authors') requirements (spherical not potato, and massively larger besides), but (it orbits the Earth not the Sun, barycenters and smartasses notwithstanding).

Rendered perhaps a bit more simply: LOL, even our moon is bigger than your dwarf planets. Nobody care, GTFO Pluto and Gang!

Re:Let it go (4, Funny)

Nadaka (224565) | more than 4 years ago | (#31790026)

The moon does not orbit the earth, nor the sun. The earth doesn't orbit the sun for that matter.

The earth/moon system orbits its barycenter and that barycenter, the sun and barycenter of the other planet systems orbit the combined barycenter of the solar system.

I am technically correct, and that is the best type of correct.

Re:Let it go (1)

Red Flayer (890720) | more than 4 years ago | (#31790276)

I am technically correct, and that is the best type of correct.

No, that is the worst kind of correct. It does not allow one to make up different interpretations to confirm our pre-existing beliefs. The best kind of correct is when the correctness leads to the maximum of amount of feel-good among believers.

*This post is ambiguously serious. This is the best kind of serious.

Re:Let it go (0)

Anonymous Coward | more than 4 years ago | (#31790556)

Shame on you for not recognizing a Futurama reference. Please surrender your geek card immediately.

Re:Let it go (2, Funny)

Red Flayer (890720) | more than 4 years ago | (#31794098)

Shame on you for not recognizing a Futurama reference. Please surrender your geek card immediately

Aw, crap. Please, can I get an exception this one time? Please?

I've been a little busy building and programming my fleshy robot companion, so I'm behind a couple seasons on watching Futurama and other nerd canon.

I promise I'll get caught up as soon as I get the hip actuators working properly.

Re:Let it go (0)

Anonymous Coward | more than 4 years ago | (#31790292)

That's like saying that a technical virgin [urbandictionary.com] is the best type of virgin.

Actually, you might be on to something here...

Re:Let it go (1)

MartinSchou (1360093) | more than 4 years ago | (#31792876)

The moon does not orbit the earth [...] The earth/moon system orbits its barycenter

And where, pray tell, is the Earth/Moon barycenter?

Why, Nadaka, it's 1,710 km below the surface of the Earth. I'm pretty sure that qualifies as "The Earth".

The Earth/Sun barycenter is below the surface of the Sun (449 km from the center), and I'm pretty sure that qualifies as "The Sun".

So you're not technically correct in saying that the Moon doesn't orbit the Earth or the Earth doesn't orbit the Sun. But you are, technically, an idiot.

Re:Let it go (1)

Tablizer (95088) | more than 4 years ago | (#31793406)

I bought a Russian space trip to this "Bary's Center" place that's allegedly so important, and it turned out there was nothing there. No refund allowed either. Thus, as far as I'm concerned, it doesn't exist! Bary moved, folks.

Re:Let it go (0)

Anonymous Coward | more than 4 years ago | (#31790068)

The moon orbits the Earth and the sun.

Re:Let it go (1)

GigaplexNZ (1233886) | more than 4 years ago | (#31790468)

must not be a satellite of another planet

This point emphasizes it better.

Pluto is pissed (3, Funny)

tpstigers (1075021) | more than 4 years ago | (#31789262)

And is forming a gang. We could be in big trouble here.

The gang shall be called (3, Funny)

spun (1352) | more than 4 years ago | (#31789280)

Snowy cold and the several dwarfs.

Re:Pluto is pissed (1)

thijsh (910751) | more than 4 years ago | (#31789408)

So that's why mother earth never goes out anymore, she's afraid of the gang of dwarf planets hanging around the neighborhood.

Re:Pluto is pissed (1)

GodfatherofSoul (174979) | more than 4 years ago | (#31790406)

A cold-blooded gang of hoodlums cruising around the neighborhood waiting to drop in unannounced.

Re:Pluto is pissed (1)

jimbolauski (882977) | more than 4 years ago | (#31790988)

We represent the dwarf planet guild
the dwarf planet guild the dwarf planet guild
I just hope Pluto doesn't hang itself.

Demotion? (1)

K-Mile (906254) | more than 4 years ago | (#31789284)

Why is Pluto in for another demotion? It still fits the proposed Dwarf Planet description, right?

Re:Demotion? (0)

Anonymous Coward | more than 4 years ago | (#31789406)

He will soon be a midget.

Re:Demotion? (4, Insightful)

reverseengineer (580922) | more than 4 years ago | (#31789908)

It wouldn't be demoted in terms of moving out of its present category. I think the sense is more that the class of dwarf planets, which now comprise only five known objects (Ceres, Pluto, Haumea, Makemake, and Eris) would admit many more members if the minimum radius necessary for the category were revised far downward. The argument then is that the category would be somehow less "special" if there were hundreds or thousands of dwarf planets instead of a handful.

At least from an aesthetic viewpoint, I actually like this proposed new definition though- the size at which an object forms a spherical shape under its own gravity seems like a significant transition. I feel that if an icy sphere the size of Enceladus were discovered out in the Kuiper belt, an assignation of "dwarf planet" would be logical, but such an object would be considered too small under the current IAU definition.

Re:Demotion? (0)

Anonymous Coward | more than 4 years ago | (#31794482)

What's so special about dwarf planets? What about the elf planets and the pixie planets? I think they would be much more interesting...

Re:Demotion? (1)

GigaplexNZ (1233886) | more than 4 years ago | (#31790532)

It's not demotion if you are purely going via the name of the title, but it is demotion if you are going by what the title actually means.

Re:Demotion? (1)

jellomizer (103300) | more than 4 years ago | (#31790766)

I was thinking the same thing too. A demotion in the sense that you got other people promoted to your level and you got nothing.

I had no idea. (1)

Dr Caleb (121505) | more than 4 years ago | (#31789292)

I knew where the Planet of the Apes was, but I had no idea where the Planet of the Dwarfs was.

Thanks!

nobody tosses a dwarf planet off the list (3, Funny)

jollyreaper (513215) | more than 4 years ago | (#31789326)

Plutoids ain't got no reason to live.

This (1)

Hognoxious (631665) | more than 4 years ago | (#31789342)

This is just totally fucking unfair. Leave Pluto alone!!!!!

Nyah Nyah Pluto's Got A Small Winkie (0)

Anonymous Coward | more than 4 years ago | (#31789350)

Fuck you Pluto.

Yeah, you.

Dwarrrrrrffffffffffffffffffffffffffff!

Better name (3, Funny)

jlebrech (810586) | more than 4 years ago | (#31789504)

Just name them potato planets.

Re:Better name (0)

Anonymous Coward | more than 4 years ago | (#31790788)

"Spud planet" has fewer syllables. You could even condense it down to "splanet."

Re:Better name (1)

Kaki Nix Sain (124686) | more than 4 years ago | (#31792862)

"Potanets"

Bad Astronomy, Bad Taxonomy (5, Interesting)

syousef (465911) | more than 4 years ago | (#31789542)

I for one couldn't care less what category Pluto falls under. Planet, Dwarf Planet, Pototoid, Potato Chip. Who cares. I have no emotional attachment.

What I do care about is bad science and bad classification. The current definition stinks. The problems I have

1. A 'dwarf planet' is not a subclass of 'planet' as one would expect from the name. It should have been named something different.
2. The definitions refers to our the sun. Not the star which the planet orbits but 'the sun'. That makes it sound like extrasolar planets are not planets either.
3. The definition of planet requires that the body has cleared it's orbit. So while it is forming early in the solar system it is not a planet then one day "poof" by magic we have a planet.
4. The draft proposal was nothing like the final proposal. The definition was passed on the last day of that IAU conference when lots of scientists had already gone. That suggests a political pissing match rather than well thought out science.
5. The definition is not consistent with what had been taught for decades, and there was no good reason for that.

I have an Astronomy degree that I did for fun and that I have never used professionally. I lost all respect for the IAU on the day they released their crappy definition.

Re:Bad Astronomy, Bad Taxonomy (0)

Anonymous Coward | more than 4 years ago | (#31789914)

I for one couldn't care less what category Pluto falls under. Planet, Dwarf Planet, Pototoid, Potato Chip.

Pluto is a Dog... or is it a God? I'm having a dyslexic moment here, don't mind me. All I can say is thank Dog for automatic spell check. :)

Re:Bad Astronomy, Bad Taxonomy (2, Insightful)

dkleinsc (563838) | more than 4 years ago | (#31790018)

I'm fairly certain the 'dwarf planet' classification was so-named because it was a foolish compromise with those who wanted to believe that Pluto was still a planet, because they'd been taught for generations that there were 9 planets. If I remember correctly, changing Ceres from being a planet to an asteroid to a dwarf planet wasn't anywhere near as controversial.

Re:Bad Astronomy, Bad Taxonomy (1)

mdwh2 (535323) | more than 4 years ago | (#31797428)

But then there was the foolish compromise in order to not simply add more planets to the list, because they'd been taught for generations that there were only 9 planets.

Re:Bad Astronomy, Bad Taxonomy (2)

John Hasler (414242) | more than 4 years ago | (#31797632)

What was foolish was attempting to come up with an algorithmic definition of planet instead of accepting that a planet (in our solar system) is any one of the nine objects on the list of planets.

Re:Bad Astronomy, Bad Taxonomy (1)

LihTox (754597) | more than 4 years ago | (#31798088)

They should just call Pluto an "honorary planet", give it a plaque and a gold watch, and be done with it.

Re:Bad Astronomy, Bad Taxonomy (0)

Anonymous Coward | more than 4 years ago | (#31790280)

5. The definition is not consistent with what had been taught for decades, and there was no good reason for that.

Didn't the old definition have problem 2 also? Overall you seem overly negative. Try to see what's good about the new definition, and not just what's bad about it.

Re:Bad Astronomy, Bad Taxonomy (1)

GigaplexNZ (1233886) | more than 4 years ago | (#31790562)

The definition of planet requires that the body has cleared it's orbit. So while it is forming early in the solar system it is not a planet then one day "poof" by magic we have a planet.

The moon still keeps getting in the way of the Earth. Perhaps we should demote ourselves too.

Re:Bad Astronomy, Bad Taxonomy (1)

Sparklepony (1088131) | more than 4 years ago | (#31791000)

An object can be "cleared" from another object's orbit without actually leaving the physical proximity of the other object. It suffices that the dynamics of the situation are such that there's no chance that the two objects will ever collide. This means that both moons and objects in resonant orbits (eg Jupiter's Trojan asteroids, which are in a 1:1 resonant orbit, and Pluto, which is in a 3:2 resonance with Neptune) are considered "cleared" from a planet's orbit.

There actually are more rigorous ways of defining and measuring the degree to which a planet has cleared its orbit, or the degree to which a planet is capable of clearing its orbit. You can see a good summary of them here: http://en.wikipedia.org/wiki/Clearing_the_neighbourhood [wikipedia.org] . I expect the Stern-Levison method is the main one the IAU had in mind since the paper describing it was presented to the IAU back in 2000. It's a mathematical formula that's applicable to any planet that you know the mass and orbital period of and gives an objective value for how capable it is of clearing its orbital neighborhood. Plotting the Stern-Levison parameters for the major bodies of the Solar System shows an orders-of-magnitude gap between the planets and the dwarf planets.

The IAU already has a separate working definition for what constitutes an "extrasolar planet", BTW: http://www.dtm.ciw.edu/boss/definition.html [ciw.edu] . It says that "The minimum mass/size required for an extrasolar object to be considered a planet should be the same as that used in our Solar System." So probably the 2006 IAU definition of Sun-orbiting planets already applies to extrasolar ones even though the 2006 definition explicitly required planets to orbit the Sun. It just doesn't matter much yet because we generally can't detect anything small enough around other stars to be considered borderline.

Re:Bad Astronomy, Bad Taxonomy (1)

GigaplexNZ (1233886) | more than 4 years ago | (#31791166)

Wow, that was a rather informative way to destroy an attempt of a joke.

Re:Bad Astronomy, Bad Taxonomy (1)

syousef (465911) | more than 4 years ago | (#31795462)

I think you'll find that what's actually occurred here is that just as a "dwarf planet" is technically not a planet, an "extra-solar planet" also doesn't fit the definition and therefore also isn't technically a planet.

A good definition makes things clearer. This definition clearly fails by that criteria.

Also my point about clearing the orbit was more about the formation of the planet. Even with a solid body formed and most of it's mass present, if it's still part of the solar disk and still subject to bombardment it is not a planet. What the hell it is during the early part of solar disk evolution isn't clear.

Re:Bad Astronomy, Bad Taxonomy (1)

Sparklepony (1088131) | more than 4 years ago | (#31796570)

Extrasolar planets have a whole other definition that was established just for them already. If you've got a problem with that one, arguing about the 2006 definition of solar planets instead is kind of pointless. The extrasolar one is labeled as a "working" definition anyway so I doubt there's much controversy over the fact that it's not very good yet.

The Stern-Levison parameter of an object is unaffected by whether it's being bombarded, it's only meant to show the object's orbit-clearing capability. Unsurprisingly, now that billions of years have passed since our solar system formed, objects with high orbit-clearing capability happen to have orbits that are clear of other debris. But Earth would have had the same Stern-Levison parameter four and a half billion years ago as it does now, so by that measure it's quite clear what it would have been.

It's probably not a productive exercise to try to figure out the exact moment when a single grain of sand lands on a dwarf planet and makes it into a planet. The current definition has a clear bimodal distribution to it which is probably the best we can hope for for something like this.

Re:Bad Astronomy, Bad Taxonomy (1)

syousef (465911) | more than 4 years ago | (#31805272)

So an extra-solar planet is not a planet. A dwarf planet is not a planet. Why the hell does the word planet appear in the definition? It's unnecessarily confusing and you are defending the indefensible. This is exactly the kind of stupidity that gets scientists labelled as socially incompetent propeller heads.

Re:Bad Astronomy, Bad Taxonomy (1)

unixan (800014) | more than 4 years ago | (#31790730)

2. The definitions refers to our the sun. Not the star which the planet orbits but 'the sun'. That makes it sound like extrasolar planets are not planets either.

Given that we don't have much information about extrasolar planets yet, making up such definitions is bad science in general, not just bad astronomy.

We aught to survey another system by probe before determining whether our local definitions apply to other systems. Especially, for example, rules for small objects determined by politics.

Re:Bad Astronomy, Bad Taxonomy (1)

Jiro (131519) | more than 4 years ago | (#31790738)

Specifically referring to our sun and not to any primary star was done on purpose. After all, there's really no way you can tell whether something in another solar system has cleared its orbit. If you applied the definition to other systems you'd never be able to know if anything there is a planet.

Re:Bad Astronomy, Bad Taxonomy (1)

Teancum (67324) | more than 4 years ago | (#31792222)

Which is precisely why the definition including a reference to Sol is a bad definition. Taxonomy of astronomical bodies should be made based on the physical characteristics of that body, not the evolutionary state of whatever place it happens to be located near.

I still don't get why Mercury is a planet, yet Titan isn't. Or better yet, why Mercury isn't a dwarf planet either? This was an arbitrary decision of an arbitrary definition that in the long run is going to need an adjustment when other things show up. Indeed I would argue that the definition of clearing its orbit really only applies to Mercury, as the other "major planets" all have atmospheres that could fit a better definition of a planet. Oh wait.... Titan has a substantial atmosphere too, and they didn't want to give that body a "promotion"?

As for how you can tell whether something in another stellar system has cleared its orbit, I would presume that would imply sending a probe to that star system and checking out the planetary bodies when that probe arrives. That kind of astronomical observation is merely going to take a few centuries before NASA or some other similar agency decides to make such an effort.... the definition itself doesn't necessarily have the teeth to cope when new discoveries are found (and have been found!)

I say we stick with the good an ancient definition of planets, which includes the Moon and the Sun, but not Uranus or Neptune. Something like "Visible objects that 'wander' in the sky". Then again the Space Shuttle and the ISS would fit that definition of a planet. See what a reference frame can do to really muck things up?

Re:Bad Astronomy, Bad Taxonomy (1)

John Hasler (414242) | more than 4 years ago | (#31797656)

> I say we stick with the good an ancient definition of planets, which
> includes the Moon and the Sun, but not Uranus or Neptune.

And not the Earth.

I say we stick with the traditional nine, and define "planet" as an object on the list of planets.

Re:Bad Astronomy, Bad Taxonomy (0)

Anonymous Coward | more than 4 years ago | (#31791788)

6. The definition of dwarf planet has nothing to do with its size; the only distinction between a planet and a dwarf planet has to do with what's near it. Hypothetically, there could be a dwarf planet larger than the earth.

Re:Bad Astronomy, Bad Taxonomy (1)

Tablizer (95088) | more than 4 years ago | (#31793314)

Classifications of such are mostly to make conversation and communication simpler. Technically, they are probably imprecise, but it only matters if used in the wrong context. Language is a useful lie. Trying to force language to be thorough and concise at the same time is often an impossible goal. If you want to know the size, weight, and shape of a specific "thing" in space, then ask.

That being said, I'd personally vote to call them "Kuiper belt objects" (KBO). That way one doesn't have to worry about classification conflicts with the "asteroids" between Mars and Jupiter; and size doesn't matter[1]. If they discover an Earth-sized KBO, so be it. It's just a big-ass KBO.

[1] No, I'm not subconsciously projecting personal insecurities into this.

Re:Bad Astronomy, Bad Taxonomy (1)

syousef (465911) | more than 4 years ago | (#31795402)

Yes classification is hard, human language is imprecise, but there's no need to throw the baby out with the bath water.

Another false & sensationalist headline (1)

SirGarlon (845873) | more than 4 years ago | (#31789734)

TFA says nothing about re-classifying Pluto out of the "dwarf planet" category. In fact there is no FA, only a picture. And it's quite obvious from that picture that Pluto far exceeds the 300 km radius that is the proposed threshold.

This is going to ruin Sailor Moon.... (0)

jameskojiro (705701) | more than 4 years ago | (#31789822)

I though Sailor Chibi-Moon aka. (the even more annoying sawed off munchkin version of Sailor Moon) was bad enough.

Now we are going to Have all of these Dwarf Planets represented by hundreds of annoying sawed off Sailor Scouts. Plus their names will be damned confusing. Names like: "Sailor (55565) 2002 AW", Sailor Makemake, Sailor "(84522) 2002 TC302", Sailor 50000 Quaoar. I mean what the hell is their Transomation scene going to sound like? Sailor Makemake Make-up.... That just sounds completely retarded.

Damn the dwarf planets, the sooner we can blow them all up the sooner anime will be safe again...

Re:This is going to ruin Sailor Moon.... (0)

Anonymous Coward | more than 4 years ago | (#31792234)

Anime is NEVER safe.

Too many tentacle monsters.

Re:This is going to ruin Sailor Moon.... (0)

Anonymous Coward | more than 4 years ago | (#31798008)

Names like: "Sailor (55565) 2002 AW", Sailor "(84522) 2002 TC302", Sailor 50000 Quaoar

So we'll have Sailor Scouts whose first order of business is giving out their numbers. The Negaverse will be reduced to leaving ecchi messages on their voice mail and waiting up late for them to call back.

Nice (1)

proxy318 (944196) | more than 4 years ago | (#31789886)

Dibs on the band name "Potato Radius".

Re:Nice (1)

blacksmith_tb (855386) | more than 4 years ago | (#31792668)

Just what I was thinking! And now you've got dibs on it. Oh well. "Potato Radius UK" just doesn't have quite the same ring.

In space, no one can hear you sing. (3, Funny)

moviepig.com (745183) | more than 4 years ago | (#31790000)


Dwarf Planets Accumulate In Outer Solar System

"Heigh-ho, heigh-ho..."

Re:In space, no one can hear you sing. (1)

gyrogeerloose (849181) | more than 4 years ago | (#31790500)

"Heigh-ho, heigh-ho..."

And in this case, the vacuum is a merciful thing... ;-)

Re:In space, no one can hear you sing. (1)

517714 (762276) | more than 4 years ago | (#31790722)

Disney will get you for that. They already managed to keep Pluto from being referred to as a planet.

Re:In space, no one can hear you sing. (1)

mcgrew (92797) | more than 4 years ago | (#31794594)

I heard a pimp singing that last week.

"High ho', High ho', it off to work she go..."

How the hell? (1)

Alsee (515537) | more than 4 years ago | (#31790876)

Dwarf Planets Accumulate??

What, is our solar system some sort of drive-by dumping ground for other stars' litter?

-

Re:How the hell? (1)

eleuthero (812560) | more than 4 years ago | (#31791642)

all current phase solar systems are... at least, if we get asteroids and other higher number elemental conglomerations from previous supernovas we do

Better definition: (0)

Anonymous Coward | more than 4 years ago | (#31791196)

Not Bush

More non-sense (0)

Anonymous Coward | more than 4 years ago | (#31791576)

What then we have to determine percentages of rock and ice? It'd be far simpler to say "Planets" then gives three classes. The obvious classes are Gas Giants, Rocky Planets, and Ice Planets. Why won't there be confusion between Rocky and Ice? Rocky planets in our system seem to have a small percentage of water whether ice or liquid. We only seem to have four rocky planets the real debate is over smaller planets that have a high percentage of ice. There are other rocky objects but they seem to fit the "Potato" definition so wouldn't be planets just large asteroids. Orbiting the sun would be another factor of coarse. I realize we get into shape of orbit but that's another silly hair splitting contest since no planet as a truly circular orbit. End of problem and no more splitting hairs and demoting planets due to semantics.

Is a tomato a fruit or a vegetable ? (1)

Alain Williams (2972) | more than 4 years ago | (#31791860)

Does it really matter ?

How science defines things is not always the same as how the ''common man'' calls things. For instance: botanically a tomato is a fruit, most of my friends think of it as a vegetable; also botanically rhubarb is a vegetable, most of my friends think of it as fruit.

To most people, myself included, pluto will remain a planet - I don't care what the astronomers think!

Re:Is a tomato a fruit or a vegetable ? (1)

NeoSkandranon (515696) | more than 4 years ago | (#31792684)

People think of rhubarb as a fruit? It's like red celery...

Standardize Units! (1)

Sechr Nibw (1278786) | more than 4 years ago | (#31793076)

First, this isn't a call to standardize either the SI system or the metric system globally.

Anyone else notice that the image in TFA has everything in miles, but then the little information in the actual article was always in kilometers? Also, while the article mentions radius, they never specify that's what the image is showing, nor do they state the radius of any of the things in the image, so, without outside research, you couldn't tell where Pluto falls in their discussion for certain, even if you're adept at converting miles to kilometers!

sWeX with a homo (-1, Troll)

Anonymous Coward | more than 4 years ago | (#31793162)

FreeBSD used to Achieve any of 7he corporations

I vote "Hemorrhoids" (1)

Tablizer (95088) | more than 4 years ago | (#31793332)

after all, we've got "Uranus". Since the jokes aint gonna stop, let's just go with the theme and see where it takes us.

"I have no problem with there being hundreds... (1)

RichiH (749257) | more than 4 years ago | (#31799732)

...of dwarf planets."

Well, neither do I. Noodles are fine for dinner, too.

That in and as of itself does not count very much unless said researcher is shown to be a leader of opinion and/or part of a larger consensus. I don't claim to know either way, simply wanted to point that out.

Dwarf Planets Are Planets Too (0)

Anonymous Coward | more than 4 years ago | (#31814216)

Adding more dwarf planets is in no way another demotion for Pluto. The reason is that in spite of the controversial IAU decision, dwarf planets are planets too. Dr. Alan Stern, who coined the term, intended it to refer to a subclass of planets large enough to be in hydrostatic equilibrium (pulled into a round shape by their own gravity) but not large enough to gravitationally dominate their orbits. He never intended dwarf planets to be designated as not planets at all. And he said he anticipates there being hundreds of these small planets in our solar system.

Only four percent of the IAU voted on this, and most are not planetary scientists. Their decision was immediately opposed in a formal petition by hundreds of professional astronomers led by Dr. Alan Stern, Principal Investigator of NASA’s New Horizons mission to Pluto. Stern and like-minded scientists favor a broader planet definition that includes any non-self-luminous spheroidal body in orbit around a star. The spherical part is important because objects become spherical when they attain a state known as hydrostatic equilibrium, meaning they are large enough for their own gravity to pull them into a round shape. This is a characteristic of planets and not of shapeless asteroids and Kuiper Belt Objects. Pluto meets this criterion and is therefore a planet. Under this definition, our solar system has 13 planets: Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto, Haumea, Makemake, and Eris.

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