Pluto Demoted

[Agent M]

Hey y'all, haven't been here in a while but I just wanted to let people know: Pluto is NOT a planet. Yes, that's right, Dairine's bed was not in fact sent to the PLANET Pluto, but simply a big chunk of ice. (had to make a YW joke in there somewhere, no matter how lame lol) CNN itself has said that Pluto isn't a planet, so (as Scott Westerfeld says): Plutophants, get over it. Pluto is now a dwarf planet, its orbit doesn't qualify for a "classical planet," (the big pretty REAL planets, with nice orbits that make sense)
Sorry for the bad news (hehe, I just think it's funny)
Ah, Pluto, we hardly knew thee....

[A Traveller with Magic]

In a scientific sense...I agree. Pluto's just a big ball of ice and rock, and there're tons of those that aren't planets...have they really demoted Pluto? Apparently there isn't a Pluto exhibit in the planet section of the Hayden Planetarium anymore... The last I heard of the planet debate was through a Science Friday podcast, when the IAU was voting on a proposal to make...I think it was any body that is held together only by its own gravity a planet. Which would eventually include hundreds of chunks of rock and ice...as well as letting Pluto keep its rank...although the definition wouldn't affect astronomers and the like at all.
But poor Pluto...I was Pluto in kindergarten when we were learning there were such things as planets. I got to wear a big red scarf

[Lazy Leopard]

It seems the IAU have finally come out with a resolution defining a "planet" as a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.

They go on to explain thus:

This means that the Solar System consists of eight "planets" Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. A new distinct class of objects called "dwarf planets" was also decided. It was agreed that "planets" and "dwarf planets" are two distinct classes of objects. The first members of the "dwarf planet" category are Ceres, Pluto and 2003 UB313 (temporary name). More "dwarf planets" are expected to be announced by the IAU in the coming months and years. Currently a dozen candidate "dwarf planets" are listed on IAU's "dwarf planet" watchlist, which keeps changing as new objects are found and the physics of the existing candidates becomes better known.

The "dwarf planet" Pluto is recognised as an important proto-type of a new class of trans-Neptunian objects. The IAU will set up a process to name these objects.

Personally I preferred the earlier draft which left out the subjective stuff about cleared neighbourhoods and included a little clarification about when objects in orbit around each other were satellites...

I guess we'll get used to it though.

[magicmaster]

It also differs. Some scientists say that pluto is a a caputered comet. So it could just be a big ball of ice or jsut a captured comet.

[Space Cadet]

Since comets are also balls of ice, what would the difference be?

Ever since I was a small child, it has been my opinion tha Pluto is not a planet. I used to lecture adult family members on the subject until they agreed with me. I was like that sometimes.

[Sean L.]

Finally - it's not so much about the actual decision as it is about the decision. Don't follow?

Whether or not pluto (hmmm, should still be capitalized, right?) is a planet is moderately interesting, but more so that the scientific community came forth and made a straight decision - one that hopefully will be followed and adopted. One body deciding with one voice about the solar system, to me, is a sign of unity, solidarity, and good sense in the future, in case something comes up (asteroid-nets?)

[alla]

Yay, finally I think that this is a much better option than having to count Charon as a planet too - there are satellites (as in moons, not the things that we put up there) bigger than Charon - and Pluto too.

I think that the 'cleaning up the neighbourhood' thing is rather amusing. Wouldn't it mean that Neptune isn't a planet until it's got rid of Pluto?

Oh, and for those wondering, (according to my text book) Pluto is a Kuiper Belt Object, so it is similar to a comet - the Kuiper Belt is where many comets come from, but the actual definition of a comet is... well... I guess it _could be counted as a comet, then. A comet is 'A cold icy body that orbits a star'. Hmmm...

Alla

[Peter Murray]

LazyLeopard pointed out this news story about people who aren't happy with the new definition. They agree that Neptune isn't a planet. Nor is the Earth. Nor is Jupiter. And if Jupiter isn't a planet, what is?

[Tiamat]

<span class="ev_code_BLUE">I had to do a bloody artice on this...(haha, good thing I usually write up about this stuff)
My Science teacher told us.

Hear me now. and, I quote:
"A Chihuahua is small, but it's still a dog."

Totally agree. Planet should have remained with it's Planet stauts. Seesh.</span>

[the_peridexis]

tia, though the dog statement is very true (man, can those things bark...) being a planet doesn't always have to do with its size. like it was mntioned earlier, when or by whom i can't recall,:P the status of being a "planet" also has to do with its orbit. read up on it, i think a few people have already put up some links that might be helpful.

i am going hooooome! bye-bye, jordan...that was off topic, but spare me. oh, and i got an 85% on my exam! i know that sounds like it sucks, but you gotta cut me some slack...i m the youngest to ever go to this institue, i am in the summer term, which is intensive, and arabic is HARD. *grin* oh, but i'll miss the people i met here....

-peri

[Dragon Writer]

wow...I've never really thought of pluto as anything but a planets. so...how many planets are there now? i mean, i know without pluto it's eight, but apparently they've found a couple new ones or something so...*IS glad to not be in astronomy right now*

[bluesalamanders]

I don't get why it's such a big deal, really. We didn't know about the Kuiper Belt and so on when Pluto was discovered, I'm assuming, right? So we didn't know that other big things would be out there. The nature of science is to grow and change, and beginning to discover all these other large Pluto-like objects (and yes, Sean, Pluto would still be capitalized; even if it's not a planet, it's still a proper noun) changes things.

I think that's what most people who are going into conniptions are upset about - change. Lots of people don't like change.

Anyone been to the Rose Center for Space and Earth at the American Museum of Natural History in NYC? I've been. I didn't notice, until it was pointed out to me, that they left Pluto out of their Hall of Planets when they remodeled the place several years ago. Most people don't notice. And I was pretty into astronomy when I was younger, too.

Blue~

[Sean L.]

So you're saying that this change has actually been coming about for a while, Anna, and this was just the final name in Pluto's (thank you) coffin?

Change is not always for the better, of course; but aside from costing textbook makers some money, I don't really think it'll affect anyone else much.

[the_peridexis]

true. it won't affect our daily life evry much, unless you happen to be a fanatical astronomer. maybe the reason we're also interested is because of how long Pluto, as a planet, has existed. since the time of the Greeks, Pluto has been admired, wild tales of faraway greatness spun. so even though many poeple dislike change, i think the reason everyone is so excited i because something that's been aroung for a long time, that textbooks and science fiction reads have raved about, will be turned into something different than what we've known it to be for so long. so...if that made any sense at all...i'll go. :P

-peri

[Peter Murray]

Originally posted by the_peridexis:
maybe the reason we're also interested is because of how long Pluto, as a planet, has existed. since the time of the Greeks, Pluto has been admired, wild tales of faraway greatness spun.

Uh, Clyde Tombaugh discovered Pluto in 1930. While it's certainly been there a lot longer, the Ancient Greeks didn't know about it.

I'm not that bothered about Pluto being demoted. As pointed out in this BBC news story, the condition that Pluto failed is also failed by Jupiter (formerly the biggest planet, now the biggest dwarf planet) and the Earth (where I live, so I have an interest in it). So they're the two ex-planets I'm more bothered about.