The Sun's 10th Planet... Sedna?

A lot of astronomers don't want to count Pluto by Anonymous Coward · 2004-03-14 05:27 · Score: 5, Interesting

So why should we start counting an even smaller "planet"? Pluto gets grandfathered in, and that's it.

Re:A lot of astronomers don't want to count Pluto by Concerned+Onlooker · 2004-03-14 05:30 · Score: 4, Funny

You exclusive club-types are all alike....

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Re:A lot of astronomers don't want to count Pluto by WorkEmail · 2004-03-14 05:36 · Score: 5, Funny

I say we put up a huge sign next to the Sun that says "You must be at least this big (insert huge red line) to ride this ride."
Re:A lot of astronomers don't want to count Pluto by c1ay · 2004-03-14 06:20 · Score: 4, Insightful

So where's the line between asteroid and planet? IMO, Pluto should be labeled an asteroid since it's smaller than even our own moon. Of course, there are also asteroids with moons but yet, they are considered asteroids, not planets. And what makes a comet a comet and not an asteroid, it's orbit? It would certailny seem that agencies like NASA that are so concerned with being precise in other areas could could come up with a more precise classification system.

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Re:A lot of astronomers don't want to count Pluto by Rick+the+Red · 2004-03-14 06:23 · Score: 4, Informative

Comets are snowballs; asteroids are rocks. Oversimplification, but you get the idea.

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Re:A lot of astronomers don't want to count Pluto by Jesus+2.0 · 2004-03-14 06:34 · Score: 5, Insightful

Pluto should be labeled an asteroid since it's smaller than even our own moon.

Frankly, I don't understand this line of reasoning. Why does it matter, with regards to whether something is a "planet" or not, whether that thing is bigger than, for example, our moon?

And "asteroid"? Pluto is far, far larger than anything currently considered an "asteroid".

Jupiter and Saturn both have moons that are bigger than Mercury. Do you not consider Mercury to be a "planet", either?

What if Jupiter had a moon bigger than Earth? That's not unimaginable; would Earth then not be a "planet"? In fact, would then nothing be a "planet" except Jupiter, Saturn, Uranus and Neptune?

I frankly don't see what's wrong with (something like) a "planet" being a non-star that's orbiting (directly) around a star. Sure, that makes for some seriously small "planets" relative to what we're used to, but at least it's not an arbitrary and useless definition like (no offense) yours.

And anyway, if you want to add back in your preferred amount of arbitraryness, you can always start referring to "major planets", "minor planets", and so forth.
Re:A lot of astronomers don't want to count Pluto by r2vf · 2004-03-14 06:47 · Score: 5, Informative

IMO, Pluto should [shouldn't?] be labeled an asteroid since it's smaller than even our own moon [wikipedia.org].
An interesting point, though to be fair, its an arbitrary cutoff. There are moons elswhere in our solar system larger than Mercury, which is indisputably a planet, for example. Also its worth pointing out that our moon is large enough that it and Earth are sometimes called a double planet. Consider this, Luna does not orbit Earth as near the equator as is usual among most other moons. Also, peculiar to all 138 known moons with the exception of Charon, it possesses an orbit where the effect of the Sun's gravity is greater than that of Earth's. Without their host planets, they would float off, wheareas the moon would continue orbiting the sun quite contently.
Re:A lot of astronomers don't want to count Pluto by catbutt · 2004-03-14 07:27 · Score: 4, Insightful

So where's the line between asteroid and planet?

Why does there have to be one? Man's tendency is to compartmentalize things, to make sure everything has a name and that name is unambiguous. Problem is, nature doesn't cooperate. There are always going to be intermediate forms, so there are never going to be definitions that aren't arbitrary.

Same thing applies to species. The nice simple definition "if it can interbreed, its the same species" doesn't always work, and there is no reasonable definition that covers all cases and removes ambiguity.
Re:A lot of astronomers don't want to count Pluto by el-spectre · 2004-03-14 07:46 · Score: 3, Informative

To be fair, luna is also the closest moon to the sun by a hundred million miles...

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Re:A lot of astronomers don't want to count Pluto by mysticgoat · 2004-03-14 07:50 · Score: 4, Insightful

Quoth grandparent: Pluto should be labeled an asteroid since it's smaller than even our own moon.
Quoth parent: Frankly, I don't understand this line of reasoning. Why does it matter, with regards to whether something is a "planet" or not, whether that thing is bigger than, for example, our moon?

I agree with parent that in this case size really doesn't matter: it's all in how you use what you got.
Historically, Neptune was discovered because it was perturbing Uranus' orbit: its existence was theorized long before it was directly observed. Similarly, Pluto was discovered because it was found that Neptune alone was not sufficient to account for all of Uranus' irregularity. While Pluto isn't very big, its size and orbit are such that it definitely affects the other planets.
In practice then, what we have actually used to distinguish a planet like Pluto from a large body that is not a planet, like Chiron (roughly as big, discovered 1977), is whether the object interacts in a measurable way with known planets. If it does, then accord it planet status because it is clearly part of the planetary system.
In view of this, the new discovery is probably not a planet, unless it has a weird orbit like Pluto and would account for some of the remaining difference between planetary observations and expectations.
But what do I know? IANAA.
Re:A lot of astronomers don't want to count Pluto by CrazyTalk · 2004-03-14 08:06 · Score: 4, Interesting

I remember hearing awhile back when the debate was raging about Pluto that to be a planet, the object has to be sufficently large so that gravitational forces caused it to form in the shape of a sphere. So, varous small hunks of debris orbiting the sun definately are not "Planets". At the other end of the spectrum, objects large enough to radiate a certain amount of heat are considered stars. Neither of these definitions are exact, and the astronomy dictionary will probably need to be rewritten with all the recent scientific discoveries emerging, but there are some definitions out there that are not completely arbitrary.
Re:A lot of astronomers don't want to count Pluto by Loconut1389 · 2004-03-14 08:50 · Score: 2, Insightful

I think it should be something like this.. If a uniformly round object's primary orbit is an orbit of our sun and meets X size requirement, it is a planet. This excludes moons that way since its primary orbit is not around the sun. Then theres just a size disctinction.. but i think aside from space debris anything larger than a few miles around should be considered a planet.
Re:A lot of astronomers don't want to count Pluto by Guppy06 · 2004-03-14 08:54 · Score: 4, Interesting

"asteroids are rocks"

We should use this for the demarkation between "asteroid" and "planet." An asteroid is one big chunk of rock. A planet is a bunch of little rocks held together by their own gravity.

If Pluto primarily orbits the sun and it's dense enough to hold on to an atmosphere from time to time, why shouldn't it be considered a planet?
Re:A lot of astronomers don't want to count Pluto by Reivec · 2004-03-14 09:04 · Score: 3, Insightful

If I were the one to classify it (and I am obviously not). I would have to base whether it is a planet or not on what it is made up of and how it came to be. If it is simply a fragment from some other large body then I wouldn't call it a planet, but it was formed from the birth of a solar system (any solar system), I would call it a planet. I say any solar system because it could be a planet from another system that left its orbit and then ended up in orbit around our sun, which is a likely case with pluto. Pluto was probably a moon from something else that left its orbit and entered orbit around our sun, which accounts for it strange orbit. But if Sedna appears to be in independent creation and not just a chunk of something else, I would call it a planet, no matter its size.
Re:A lot of astronomers don't want to count Pluto by GigsVT · 2004-03-14 09:16 · Score: 3, Funny

not sufficient to account for all of Uranus' irregularity.

I'm trying to eat more fiber OK? I wish you would stop talking about this stuff in public!

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Re:A lot of astronomers don't want to count Pluto by Anarke_Incarnate · 2004-03-14 09:18 · Score: 2, Informative

And some planets are not much more than super dense gas. About the only thing solid on them is their subzero cores which contain things such as frozen/metallic hydrogen.
Re:A lot of astronomers don't want to count Pluto by Entropy2016 · 2004-03-14 09:27 · Score: 4, Interesting

I've got a couple possible solutions regarding the debate over labeling something a planet.

1. Why not just call all solid [and liquid?] bodies "satellites" ? Asteroid, planet, moon, deathstar, they're all satellites from now on.

OR

2. Redefine "Planet" to mean: Any satellite of a star with enough mass to retain an atmosphere of any [detectable?] pressure.

Rocks come in all sizes, so we ought to ditch the term or define it with respect to something as arbitrary as size.

Our universe is hopelessly complex. Accept it. Part of life as a human is dealing with a world that impossible to fully predict or control. If we didn't have such a world, things would be far less interesting. (we might even be wishing that there would be issues to debate).
Re:A lot of astronomers don't want to count Pluto by pfdietz · 2004-03-14 09:37 · Score: 3, Informative

There are no planets with 'subzero cores'.
Re:A lot of astronomers don't want to count Pluto by Martin+Blank · 2004-03-14 10:24 · Score: 4, Informative

A large number of known asteroids are exactly that: clumps of rock weakly held together through their own weak gravitational forces.

This incidentally leads to one of the fears of trying to deflect such an asteroid were it on a collision with the earth -- that it would simply fragment it and cause destruction on a wider scale.

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Re:A lot of astronomers don't want to count Pluto by Yunzil · 2004-03-14 10:48 · Score: 4, Informative

Similarly, Pluto was discovered because it was found that Neptune alone was not sufficient to account for all of Uranus' irregularity.

Actually, no. When Pluto was discovered it was found to be too small to account for the irregularity in Uranus's orbit. When they went back and checked, they found there had been a mistake and there wasn't any irregularity to start with. The discovery of Pluto was an accident.
Re:A lot of astronomers don't want to count Pluto by marine_recon · 2004-03-14 12:48 · Score: 2, Interesting

astroids are planitods (sic) the term astroid has gained popularity dispite its innaccurcy

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Re:A lot of astronomers don't want to count Pluto by squiggleslash · 2004-03-14 13:03 · Score: 2, Insightful

2. Redefine "Planet" to mean: Any satellite of a star with enough mass to retain an atmosphere of any [detectable?] pressure.
Where would that leave Mercury? The nearest thing it has to an atmosphere are little particles being blasted off it by the solar wind. I suspect, ultimately, many things we wouldn't regard as planets are likewise.

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Re:A lot of astronomers don't want to count Pluto by Shakrai · 2004-03-14 13:36 · Score: 2, Interesting

This incidentally leads to one of the fears of trying to deflect such an asteroid were it on a collision with the earth -- that it would simply fragment it and cause destruction on a wider scale.
I'd perfer low-level destruction on a wide-scale to massive life-ending destruction on a Worldwide scale thank you very much.

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Re:A lot of astronomers don't want to count Pluto by salimma · 2004-03-14 14:18 · Score: 2, Informative

A planet is a bunch of little rocks held together by their own gravity.

We don't know that the gas giants even have solid rocky cores underneath...

But yes, a mass body substantial enough to hold on to an atmosphere could be a valid definition of a planet. Not *the* valid definition since we have planets like Mercury buffeted by solar winds..

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Michel
Fedora Project Contribut
Re:A lot of astronomers don't want to count Pluto by SEWilco · 2004-03-14 19:07 · Score: 5, Funny

Yes, it would be so much better to just reshape the incoming rock into a long needle so we have destruction confined to only two tiny little spots, including the spot on the opposite side of the Earth.
Re:A lot of astronomers don't want to count Pluto by 1u3hr · 2004-03-14 21:09 · Score: 4, Informative

I'd prefer that. In an extreme situation, where the object would be fragmented to a bunch of dust & powder, everything would get burned up in the atmosphere. I could be wrong, but that's where I'm placing my bets.
From Phil Plait's Bad Astronomy: Review of Deep Impact:
This was the Biggest Baddest Astronomy in the movie. Blowing up a comet does no good at all, and might even make matters worse. Just because the pieces are smaller doesn't mean you have changed anything. If every piece still impacts the Earth (by that I mean actually is stopped by the Earth or its atmosphere) you are still dumping all the kinetic energy of The Comet into the Earth's atmosphere! That's a HUGE amount of energy, dumped in practically all at once. It would still create a massive explosion, dwarfing all of our nuclear bombs combined. Even if you could somehow soften the blow, all that heat would wreak havoc with our weather. Some people actually think it might be better to simply let a big one hit rather than blow it up, because the Earth itself can absorb the energy of impact better than the atmosphere can. This is still argued, though. I'd prefer not to try any experiments!
Re:A lot of astronomers don't want to count Pluto by mysticgoat · 2004-03-15 03:55 · Score: 2, Insightful

When Pluto was discovered it was found to be too small to account for the irregularity in Uranus's orbit. When they went back and checked, they found there had been a mistake and there wasn't any irregularity to start with. The discovery of Pluto was an accident.
Above statement adds confusion to a complicated history. The second sentence is flat out wrong.
Pluto was found in a deliberate search for a nineth planet that would account for the pertubations of Neptune and Uranus. It was found fairly close to where the predictions said it should be.
But Pluto has neither the mass nor the orbital characteristics the predictions called for. (This was confirmed with the discovery of Charon and observations of the interactions of Pluto and Charon.) In a sense Pluto's discovery was accidental for its real orbit matches the predicted orbit for only a little while: it was fortunate that people were looking for it during those decades.
The second statement in quote from parent is false: there are significant pertubations in the orbits of Uranus and Neptune, and also in Pluto's orbit. All three of these consistently fail to be where their ephemerides predict they should be. The irregularities (pertubations) are definitely there. Something else is out there. Perhaps a lot of small stuff in a lumpy distribution; perhaps a few pieces approaching planetary size.

Woop de fucking do! by Operating+Thetan · 2004-03-14 05:27 · Score: 5, Funny

Cue conspiracy theories, New Age freaks, Planet X believers and other idiots. Still, at least this discovery has the redeeming quality of completely fucking up astrology

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Re:Woop de fucking do! by Amiga+Lover · 2004-03-14 05:29 · Score: 4, Interesting

I want to know what happened to Quoaor or whatever the hell it's name is. wasn't it planet 10 last year?
Re:Woop de fucking do! by Snowspinner · 2004-03-14 05:35 · Score: 5, Funny

Yeah, it'll probably cost a lot to reprint all the New Age ancient traditions to include a tenth planet.

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Philip Sandifer's academic website
Re:Woop de fucking do! by beebware · 2004-03-14 05:35 · Score: 3, Funny

It was called Rupert.
Re:Woop de fucking do! by JayBlalock · 2004-03-14 05:37 · Score: 2, Informative

It was only something like 1,400 klicks across, if memory serves. So this new find does at least have the distinction of being substantially larger.

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Re:Woop de fucking do! by Anonymous Coward · 2004-03-14 05:48 · Score: 3, Funny

Yeah but just think of all the new Christian derivatives that can arise! 10 COMMANDMENTS! 10 PLANETS! COINCIDENCE? I think not.

Please send donations now to my paypal account to start our new church.
Re:Woop de fucking do! by Anonymous Coward · 2004-03-14 05:49 · Score: 5, Interesting

Yeah, it'll probably cost a lot to reprint all the New Age ancient traditions to include a tenth planet.

Ten Planets? You haven't been keeping up with here astrology has been going the last twenty-fove years. I know astrologers who use twenty planets, most of which are imaginary. [ Dutch School of Astrology. Germans School of Astrology. The Planets of Alice Bailey, and related flakes.]

This, of course, ignores the two hundred or so asteroids which new age astrologers use. And don't forget the plethora of comets, meteor showers, deep space objects, and other things that may, or may not exist.

And to be sure that you haven't forgotten anything, there are umpteen "Arabic Parts", Midpoints, Orbs, harmonics, ( or something like that) etc.

In short, roughly 10^8 objects that no self-respecting astrologer would omit, if one believes in the validity of all the books on astrology that have been published.
Re:Woop de fucking do! by cybermace5 · 2004-03-14 05:57 · Score: 5, Interesting

Wanna know what will REALLY give the conspiracy theorists, New Age freaks, etc? "Sedna" is "Andes" spelled backwards! Everyone knows the advanced Inca civilization lived in the Andes mountains, and there are more than enough wacky theories about the Incas involving aliens and whatnot. Oooh...why is an Inuit god named after backwards-Andes...are the Inuits actually Inca refugees? They're close the Pole, too, and there are already crazy theories about a hole to the interior of the earth where advanced civilizations live, and the Eskimos are somehow related....

Yeah, can't imagine a worse name, really. Backwards-spelled stuff is pure gold in the conspiracy community.

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Re:Woop de fucking do! by S.O.B. · 2004-03-14 05:58 · Score: 5, Funny

But then the evolutionists would respond with, "10 planets, ten fingers. Coincidence?"

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Re:Woop de fucking do! by Tablizer · 2004-03-14 05:59 · Score: 2, Funny

The research is probably funded by the companies that make Solar System mobile kits so that you have to buy an updated mobile. Maybe they should name the new sphere "Microsoft" in honor of that technique :-)

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Re:Woop de fucking do! by Jesus+2.0 · 2004-03-14 06:43 · Score: 3, Funny

The way astrology works is ... not at all?
Re:Woop de fucking do! by John+Courtland · 2004-03-14 07:14 · Score: 2, Insightful

Gotcha. Yeah, I don't buy into the tree of life matching with planets. Doesn't make sense.

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Re:Woop de fucking do! by osgeek · 2004-03-14 08:01 · Score: 4, Insightful

Now, of course that seems like hogwash, and maybe it is, but it is pretty accurate

Bullshit. If it's accurate, then you could come up with a test to prove it. You could take astrological predictions for an individual based upon his house and compare them with random predictions. These could then be compared for statistical validity, proving once and for all that astrology is accurate.

Wow, if only someone would take the time to perform tests like these. Maybe someone could even make a contest to offer money to anyone who could prove a fantastic claim like "astrology is accurate".

Get it through your skull. It's PROVEN TO BE bullshit. It's always been bullshit, and it will always be bullshit. I've had close dealings with astrologists. I know how some of what they say can seem to be more than just coincidence, but that's all it is -- coincidence and psychology. It's got nothing to do with anyone's "house" or "fate". It's all just bullshit. Don't be a sucker.

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Re:Woop de fucking do! by Snowspinner · 2004-03-14 12:48 · Score: 2, Interesting

In mild defense of astrology, someone like Randi who actively seeks to debunk astrology and the supernatural is probably not terribly invested in designing a fair test. I mean, let's face it - his goal is not to determine whether or not astrology is accurate - his goal is to repeatedly show it is not.

Which is not good science - it's not objective. Which is where a lot of the science/religion conflict comes up. Each side really wants to disprove the other side.

In the end, they're equally based on unprovable assumptions. (Go ahead - prove that the world as you observe it corresponds to objective reality.)

The best that can be said is that, given a set of premises that contradict the premises of astrology, astrology is false.

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Philip Sandifer's academic website

How could by j_sp_r · 2004-03-14 05:27 · Score: 2, Insightful

nobody has seen it before. This is not very far from earth compared to where Hubble looked latly. I'm far more interested in what's around us then far away (except when there is life there)

Re:How could by dreamchaser · 2004-03-14 05:30 · Score: 4, Insightful

Because you have to be looking at the right place at the right time. Do you have any idea how vast a volume of space we're talking about?
Re:How could by phch · 2004-03-14 05:34 · Score: 5, Insightful

It's always been hard to see distant planets because they don't emit light. Hubble can see distant galaxies because they contain lots of luminous objects.
Re:How could by imsabbel · 2004-03-14 05:34 · Score: 2, Informative

"FAR" is a very vague thing in space.
Yes, its near, but its small and its cold. So its only to detect if you are looking EXACTLY at it.
A blue giant a million light years away is MUCH easier to spot that that pile of cold rock.

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Re:How could by Limburgher · 2004-03-14 05:35 · Score: 4, Informative

Not to mention that in the Hubble's field of vision, a local planet would be moving much faster than a star millions of AUs out. Imagine looking through binoculars at your sexy neighbor sunbathing in her (or his) yard. You might not see the gnat flying a foot in front of you, because you're not focusing there, so it would just be a blurry fuzz, possibly ignored by the eye if visible at all.
The binoculars also limit or eliminate local vision while in use, obscuring the approach of your spouse/mother and a disapproving hand. . .:)

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Re:How could by Anonymous Coward · 2004-03-14 05:39 · Score: 2, Funny

It's even worse when I look at your Mom, because my field of vision has to be far out indeed to see her in her entirety.
Re:How could by Sqwubbsy · 2004-03-14 05:39 · Score: 4, Funny

"FAR" is a very vague thing in space.

I hear they're going to adopt the new distance measures 'hither' and 'yonder' so normal folks will have a better understanding, at least in galactic terms, of where things are.

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I wonder what is so important.... by dealsites · 2004-03-14 05:28 · Score: 5, Interesting

I wonder what is so important that NASA is going to wait until Monday. Maybe they will be unveiling something else at the same time?

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Re:I wonder what is so important.... by AnamanFan · 2004-03-14 05:35 · Score: 5, Interesting

It's a standard rule of Public Relations. Never announce anything between Friday at 4pm till Monday at 8am.

The reason being that news outlets are not at full capacity during the weekends, so any news announced over the weekend won't get as much coverage. If NASA announced the news today, it will be covered on the Sunday evening news, and never again since that piece of news was already done, even when not many saw it.

You can notice this practice when someone famous dies over a weekend. There will be an immediate announcement saying that the person is missing or very ill or something of the sort, then make the announcement on Monday.

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Re:I wonder what is so important.... by gnu-generation-one · 2004-03-14 06:21 · Score: 4, Funny

"I wonder what is so important that NASA is going to wait until Monday. Maybe they will be unveiling something else at the same time?"

It's the monthly bug-report announcement. "A local root vulnerability has been found in the astrology community. NASA rates it as non-critical"
Re:I wonder what is so important.... by Bearpaw · 2004-03-14 06:22 · Score: 3, Insightful

It's a standard rule of Public Relations. Never announce anything between Friday at 4pm till Monday at 8am.
Unless, of course, it's something you have to announce for some reason but don't want most people to hear. Then late Friday afternoon is the perfect time to announce it. Politicians do this a lot. It would probably be quite instructive to review Friday late-afternoon press releases from the White House, for the last two or three decades.

whew! by odano · 2004-03-14 05:28 · Score: 5, Funny

Thank god I am out of elementary school. Memorizing 9 planets was hard enough, but 10! They have got to be kidding.

Re:whew! by LostCluster · 2004-03-14 05:33 · Score: 2, Informative

And what about all those M-V-E-M-J-S-U-N-P mnemonics we learned. Those already had to be retrofitted to become M-V-E-M-J-S-U-P-N, now they need to extend to M-V-E-M-J-S-U-P-N-S.
Re:whew! by Anonymous Coward · 2004-03-14 05:37 · Score: 5, Funny

My very educated mother just sent us nine pizzas, sucka - Mr. T
Re:whew! by calibanDNS · 2004-03-14 06:26 · Score: 2

My Very Educated Mother Just Sent Us Nine Pizza Slices.
Re:whew! by r2vf · 2004-03-14 07:24 · Score: 2, Insightful

Those already had to be retrofitted to become M-V-E-M-J-S-U-P-N, now they need to extend to M-V-E-M-J-S-U-P-N-S.

Pluto reverted to being the planet farthest from the Sun several years ago. Now it will possibly be M-V-E-M-J-S-U-N-P-S

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Back to grade school for retraining... by LostCluster · 2004-03-14 05:29 · Score: 2, Funny

The order of planets we all learned in 4th grade was out of date already because now Neptune is further away than Pluto. Now, I guess we're going to have to memorize another planent for the next quiz.

Re:Back to grade school for retraining... by Professor_Quail · 2004-03-14 05:32 · Score: 3, Informative

Actually, they switched back in 1999; Pluto is again further away than Neptune.
Re:Back to grade school for retraining... by thomasdelbert · 2004-03-14 05:33 · Score: 5, Informative

Correction - Neptune was farther from Pluto from January 21, 1979 to Feb. 11, 1999 but at this time Pluto is farther from the sun than Neptune.

Of course, there's debate as to whether Pluto-Charon is a planet with a moon, or a double planet...

- Thomas;

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Re:Back to grade school for retraining... by mark-t · 2004-03-14 05:45 · Score: 4, Interesting

There is a simple way to decide if something is a moon or double planet. Look where the two focal points for the elipses that describe their orbits are.
If both focal points for the orbit are contained within the volume of one body, or if one focal point is contained within the volume of one body and the other focal point outside of both bodies, then the smaller object is a moon of the larger.
If both focal points are outside the volume of both bodies, or if one focal point is within the volume of one body and the other focal point within the other body, then the pair of objects should be considered a double planet.
So Pluto/Charon, following this reasoning, should be considered a double planet.

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File under 'M' for 'Manic ranting'
Re:Back to grade school for retraining... by ccady · 2004-03-14 07:23 · Score: 2, Informative

I call BS.

It is also more accurate to say that the earth and moon together revolve about their common center of mass, rather than saying that the moon revolves about the earth. This common center of mass lies beneath the earth's surface, about 3,000 mi (4800 km) from the earth's center.

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Re:Back to grade school for retraining... by mark-t · 2004-03-14 11:44 · Score: 2, Informative

Au contraire...
All cellestial bodies orbit their parent body in an eliptical orbit, not a circular one, and an ellipse has two focal points.
You are correct, however, that when looking at the the orbit of just one single object around one single other, particularly when their masses are very divergent, you can always ignore the focal point that is furthest from the heavier body.
However, when examining how multiple bodies affect _eachother_, it isn't quite as simple (it would be if orbits were circular, but they aren't).

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File under 'M' for 'Manic ranting'

Alf by TheGreatAvatar · 2004-03-14 05:29 · Score: 3, Funny

was right after all!

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Re:Alf by Lord+Kano · 2004-03-14 06:53 · Score: 2, Funny

We just discovered Alvin, how much longer until we find Dave?

LK

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Nibiru!!! by Anonymous Coward · 2004-03-14 05:29 · Score: 2, Funny

It's Planet X! It coming to Earth to cause a pole shift and kill most of us. I heard it on Coast to Coast, so it must be true.

for comparison purposes: by Anonymous Coward · 2004-03-14 05:30 · Score: 5, Informative

Pluto is 2300 km diameter, ranges from 4.3 to 7.4 billion km from the sun.

http://www.windows.ucar.edu/tour/link=/pluto/stati stics.html

It's a Kuiper object... by meringuoid · 2004-03-14 05:30 · Score: 5, Insightful

... and the last I heard was that it was about the size of Charon. I doubt it will ever be recognised as a planet - we already have Quaoar out there and swarms of other little Plutinos.

Whether Pluto is 'really' a planet or just a big Kuiper object seems to be a silly argument. Even if it's not justifiable, we'll call Pluto a planet out of tradition.

--
Real Daleks don't climb stairs - they level the building.

Re:It's a Kuiper object... by Anonymous Coward · 2004-03-14 05:38 · Score: 2, Interesting

I agree--I say stop this silly argument about what counts as a planet and what is a planetoid.

Does it really matter if we have 8, 9, or 10 planets or 8 planets and 1 or two planetoids?

I say it's more important to know they're there, what their names are, and let people refer to them as planets, planetoids, Kuiper Belt objects, or whatever they want to call them.

I know there are various arguments that the word "planet" should have a precise definition, and that you can make arguments about Pluto not being one based on things like orbit. But reality is not precise--things don't come in discrete mass sizes.

I say leave the distinction between planet and planetoid fuzzy, and focus on the objects themselves.
Re:It's a Kuiper object... by Gutboy_Barrelhouse · 2004-03-14 05:57 · Score: 5, Informative

No. Charon is slightly smaller than Quaoar.
Sedna is over 4 times the size (volume) of Quaoar.
Whether it's a planet is a silly argument, but even so, "we already have Quaoar" is really irrelevant.
Re:It's a Kuiper object... by RobertFisher · 2004-03-14 06:53 · Score: 5, Informative

The question becomes even more convolved once we move outside the solar system, since we now know of a wide diversity of systems, of which our own solar system is only one particular instance. (And perhaps not even typical at that.) We know that there are objects extending all the way down from massive stars (around 100 Msun) to hydrogen-burning stars like our sun to brown dwarfs to planets. Clearly any definition of a planet must apply not only to our solar system, but also to these extrasolar systems. Some of these systems are much like our own (for instance, they may contain a brown dwarf orbiting a star, or a planet orbiting a star), and some (including a few systems of low enough mass to qualify as a planet) are "free-floaters" -- just sitting out there by themselves in space.
I think ultimately the question is whether there is a single continuous "initial mass function" of isolated objects or not. The best idea as to how stars acquire their initial mass is that turbulence in the interstellar medium, which exists on all scales, establishes a power-law distribution of initial masses. Every once in a while, you get a very strong shock which passes by inside a giant molecular cloud and forces the collapse of a large region which then goes on to form a massive star. But more typically, you form stars more like our sun. And just as rare as massive collapses are very small mass ones which go on to form isolated brown dwarfs and free-floating planets. If this model holds up to be true, then we are all mincing words in our definitions of isolated systems, since they are all manifestations of the same universal formation process.
However, to avoid the difficult question of formation mechanisms, an IAU working group of some of the most respected people in the field established a working definition to define by fiat what it means to be a brown dwarf, and a planet. Extrasolar "planets" are those objects orbiting a star which are beneath the deteurium-burning limit -- regardless of how they are formed. "Brown dwarfs" are defined to be those which burn deuterium but not lithium, and "sub-brown dwarfs" (NOT free-floating planets!) are defined to be those isolated objects which do not burn deuterium. Even the working group itself admitted that this definition was not satisfying to a single member of the group, and so it is likely it will be replaced at a later time with something more physically-motivated. The "planet/planetismal/KBO" distinction was pushed back to our own solar system, since it will be some time before anyone sees anything that small in another system.
Also of interest is the following link, which gives a history of previous claims for additional planetary members of our solar system : SEDS.

--
Science, like Nature, must also be tamed, with a view turned towards its preservation.

trans-neptonian objects..? by opello · 2004-03-14 05:31 · Score: 2, Informative

wasn't there something quite a while back about "trans-neptonian objects" not qualifying as planets, but that the organization that determines such things stated that pluto/charon would get included, but anything else was out?

What happened to the naming convetion? by Snowspinner · 2004-03-14 05:31 · Score: 5, Interesting

I thought planets were Roman gods. It's not even like we've run out of them. We can still find Vulcan (Mulciber if you want to avoid rabit Trekkies), Juno, Minerva, Apollo (You can call this one Phoebus if you want to avoid confusing it with space probes), Diana, Vesta.

And that's before you start getting slightly obscure ones like Janus, Bacchus (Or Liber), Fanus, Quirinus, Pomona, or Vertumnus.

--
Philip Sandifer's academic website

Re:What happened to the naming convetion? by simcop2387 · 2004-03-14 05:34 · Score: 2, Funny

i for one will refuse to call it sedna, instead i'll be calling it Rupert...
Re:What happened to the naming convetion? by Limburgher · 2004-03-14 05:38 · Score: 2, Informative

Janus is already a moon of Saturn, IIRC.

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You are not the customer.
Re:What happened to the naming convetion? by hobbesmaster · 2004-03-14 05:40 · Score: 3, Interesting

IANAAP, but Vulcan is already reserved, it was a theoretical planet in the early 20th century that would be closer into the Sun that Mercury's orbit that would account for irregularities in Mercury's orbital path. There was actually no planet and Mercury's behavior is proof of the special theory of relativity (IIRC).

I'd presume that for historical reasons Vulcan would be reserved. Also recall that theres lots of trans pluto pluto sized objects that have names, I forget what the naming mechanism is for them, but I think they're roman.
Re:What happened to the naming convetion? by Sqwubbsy · 2004-03-14 05:44 · Score: 5, Interesting

Wasn't 'Apollo' considered the sun. Remember, this wasn't just a 'naming convention' but actual mythology. Apollo drove the chariot of the sun across the sky. Mars, the god of war, appeared in certain places at certain times, same with Venus.
Now that Roman mythology isn't really considered religion (outside of Berkeley) it can be a nice tradition. I mean, it's not lik the Inuit have really contributed to Western Culture except for, I guess, hockey and lacrosse.

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Re:What happened to the naming convetion? by volsung · 2004-03-14 05:58 · Score: 4, Informative

The precession of Mercury's orbit is explained by the general theory of relativity, not the special theory. The special theory explains the results of the Michelson-Morley experiment.
Re:What happened to the naming convetion? by I+don't+want+to+spen · 2004-03-14 06:13 · Score: 2, Informative

Vesta has already been used.

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Don't go to a brothel if you want to buy broth
Re:What happened to the naming convetion? by Snowspinner · 2004-03-14 06:29 · Score: 2, Informative

That would be Prometheus, but thank you for playing.

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Philip Sandifer's academic website

I claim it by AbstracTus · 2004-03-14 05:32 · Score: 3, Funny

Please email resident applications to me.

Re:I claim it by s20451 · 2004-03-14 06:07 · Score: 4, Funny

You can only call interplanetary dibs if you can see the planet as you call it. Just like calling shotgun.

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Toronto-area transit rider? Rate your ride.

Re:What, no more Roman gods? by JeffTL · 2004-03-14 05:33 · Score: 2, Insightful

I believe it's called "patronizing faux multiculturalism" -- if a Roman name for it becomes available, count on me to use it as much as possible.

They by chadseld · 2004-03-14 05:33 · Score: 4, Funny

They should call it rupert.

Re:They by eupheric · 2004-03-14 06:51 · Score: 2, Funny

no offense, but i wish there was a mod option "-1, hasn't read Mostly Harmless"

There could be a lot of stuff out there by mbone · 2004-03-14 05:33 · Score: 5, Interesting

Out in the Kuiper belt and the Oort cloud there are thought to be as many as one trillion objects - most small 1 to 10 km chucks of ice.

The really interesting question is, what is the mass distribution ? (I.e., how does the number of objects scale with their mass ?) This is basically unconstrained by real data. All such cosmic mass distributions are steep, but many (for example, planets in the Solar System, Asteroids in the Asteroid belt) are dominated by the most massive bodies.

If this holds true in the Oort cloud, in particular, there could be some pretty big objects. Even a Jupiter sized object might be able to hide from the Infrared surveys (the best way of detecting such an object).

Re:There could be a lot of stuff out there by mikerich · 2004-03-14 06:43 · Score: 3, Informative

If this holds true in the Oort cloud, in particular, there could be some pretty big objects. Even a Jupiter sized object might be able to hide from the Infrared surveys (the best way of detecting such an object).
Clyde Tombaugh who discovered Pluto performed an exhaustive search for Planet X for several decades. From his results he concluded that there were no undiscovered Jupiter-sized bodies within 470AU of the Sun, and no Neptune-sized objects with 210AU. (Pluto is never more than 50AU from the Sun).
The Oort Cloud is believed to have been populated by planetismals thrown out of the early inner part of the Solar System by the formation of Uranus and Neptune. They would have slungshot smaller bodies into the outer darkness into orbits that match the hypothetical orbits in the Oort Cloud. They would not have been able to shunt anything larger out that far - at least not without disrupting their own formation.
A further problem is that planet formation models run into trouble this far out. Distances between the planetismals that made up the proto-planets would have been so great, and relative velocities so small that its hard to see how they would ever have collided to built up a bigger planet.
Best wishes,
Mike.
Re:There could be a lot of stuff out there by juanillodgn · 2004-03-14 06:43 · Score: 2, Insightful

A Jupiter-sized object would hide from the Infrared, but its gravity, surely would not.

Re:10 is good by and+by · 2004-03-14 05:34 · Score: 2, Funny

What about those of us who prefer base 9? You're messing up our already perfect "10." =)

Question is now is there life.. by Business+King · 2004-03-14 05:38 · Score: 2, Interesting

Given that Europa is a ice world, and it might contain life under it's icy floor, we might find life there in a 100 years.

Second, these ice planets could make for good hydrogen fuel source when we finally venture out that far.....

Yuggoth found--details and photos at 11. by sudog · 2004-03-14 05:38 · Score: 2, Funny

I for one welcome our new Mi-Go masters!

Closer to home by Mr.+Piddle · 2004-03-14 05:41 · Score: 2, Funny

If people continue gaining weight, then there are millions of new objects about to get added to the astrological databases.

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Vote in November. You won't regret it.

Re:Closer to home by ScrewMaster · 2004-03-14 05:59 · Score: 2, Funny

Yes, and they're getting less and less heavenly all the time.

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The higher the technology, the sharper that two-edged sword.

Political Correctness by schnarff · 2004-03-14 05:42 · Score: 4, Insightful

I think I can answer all of the people on here who are asking "Why didn't they go with a Roman name?". It's real simple: political correctness. After all, Roman names were given to the planets by a bunch of old, dead white men, and are a vestige of a conquering, warfaring civilization. This new Inuit name represents one of those poor, marginalized, powerless indigenous tribe types. It's like affirmative action for planets.

Personally I think we should have just stuck with the Roman names and kept a consistent system...but then again, I am a middle-class white male. ;-P

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How To Get Humans To Mars

Re:What, no more Roman gods? by JayBlalock · 2004-03-14 05:43 · Score: 2, Interesting

Actually, yes. Thanks to them assigning minor moons the names of deities, they've pretty much run out of Roman gods, Greek alternates, and have even put a pretty good dent in the Norse pantheon.

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Bush: He's Liberal in all the wrong ways.

Re:What, no more Roman gods? by Concerned+Onlooker · 2004-03-14 05:44 · Score: 2, Interesting

I don't care about the Roman gods much, but I am puzzled as to why they would pick a goddess of the sea when it doesn't seem likely that the new planet holds much water. Perhaps we should name the new planet Earth and rename our own rock Sedna?

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http://www.rootstrikers.org/

Sedna? by Kirth · 2004-03-14 05:45 · Score: 2, Redundant

Well it might be nice to use a inuit-goddess, but this totally breaks the namespace. You have to use roman gods and godesses exclusively, for Jupiters sake!

We still got plenty left, by the way:
Juno, Apollo, Diana, Cupid, Minerva, Ceres, Proserpine, Vulcan, Bacchus, Vesta, Janus, Maia and Flora. Some of them might not be such a good idea, Ceres, Vulcan and Apollo are already taken in some sense. And Proserpine is the goddess of the Underworld.
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"The more prohibitions there are, The poorer the people will be" -- Lao Tse

10th planet is more fun so it is in by SmallFurryCreature · 2004-03-14 05:46 · Score: 4, Interesting

Screws up astrology and that can only be a good thing. Lets add one every 2-3 years and watch them squirm.

Anyway something 2000km in diameter is hardly small. Aren't astoroids that could kill earth just a couple of kilometers accross?

Anyway excluding it is sizeist. Can't have that. If you are going to classify keep it simple. Object larger then a rock orbetting the sun and being close to round. I think that is what most people consider a planet.

So welcome sedna.

--

MMO Quests are like orgasms:

You may solo them, I prefer them in a group.

Re:10th planet is more fun so it is in by TomHandy · 2004-03-14 06:12 · Score: 2, Funny

Hrmm, I agree screwing up astrology is always a good thing. But what if this HELPS them? What if now astrologers defend all their false "predictions" by explaining that it was in fact Sedna's influence that skewed the results?
-Tom

Not a problem yet by SiliconEntity · 2004-03-14 05:47 · Score: 4, Interesting

It won't be an issue until they find a Kuiper object that is bigger than Pluto. Then they'll have an awkward situation. Making Pluto a planet when this bigger object isn't one doesn't make sense; nobody wants to add a new planet, because in retrospect it was a mistake to make Pluto a planet, and adding another Kuiper object would just compound it; and removing Pluto from the list of planets offends tradition.

Everyone wants to push this off as long as possible, so if the new object is really smaller than Pluto, they'll breathe a sigh of relief and go on with things as they are.

I wish NASA was better at PR.. by Awptimus+Prime · 2004-03-14 05:48 · Score: 2, Interesting

First off, I was really pissed off at NASA and the media outlets for the scant coverage of the mission results concerning water on mars. All we got was a 4 minute introduction and one panelist into the release and it was back to the CNN/FOX 30 minute cycle of endless Pro-Bush news bits and Iraq coverage. Luckily, I have the NASA TV channel on satellite, so I was able to flip over -- but for the >95% of americans without NASA tv, they missed out on an hour's worth of enlightening details of Mars, straight from scientists and not tabloid writers with no understanding of science.

Now, this release isn't even going to be televised. The only initial outlet is a conference call for reporters only.

I'm ashamed of NASA and I am ashamed of our media coverage of science. When I was a kid, every space shuttle launch was televised. Taking 10-30 minutes of time out of my day to watch the occasional launch helped inspire me to think above the quagmire I was born into, to know there was something greater. Kids today get MTV and 24 hour news spin channels in 30 minute loops.

But hey, at least they get a nice, fast Internet and ~225 national channels of garbage via satellite.

Re:I wish NASA was better at PR.. by 0x0d0a · 2004-03-14 06:10 · Score: 3, Interesting

Dude, *how* can you possibly blame NASA for insufficient coverage?

They put out an entire *channel* of content and have an extensive website with tons of goodies. They have been fighting like mad to get more media coverage to ensure that they get continued funding.

If you want to blame someone, blame our current media sources or people's interests. NASA is the *least* guilty party involved in trying to expose people to information about space.

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May we never see th
Re:I wish NASA was better at PR.. by Awptimus+Prime · 2004-03-14 06:32 · Score: 2, Interesting

If you want to blame someone, blame our current media sources or people's interests. NASA is the *least* guilty party involved in trying to expose people to information about space.

So NASA could put the next release on NASA TV instead of just having a conference call with reporters. Like you say, the station is there 24/7. It's fully funded to run programming 24 hours a day, so to broadcast their findings won't cost anything.

Have you watched the NASA channel? When there's not a news release, it's 0 budget programs that appear to have been put together by students at the Hunstville summer camp. Very, very lacking and outdated programming. Then there are those 5-6 hour stretches of being able to see a NASA reporter interviewing other news networks but unable to hear the audio from the other side of the feed. Kind of like pointing your dish to random sattelites and capturing raw feeds. Totally lame, I tell you.

Now, how much do you think it would cost for them to do a Science Guy or Mr Wizard type of show? They could recruit scientists internally and make the audience and participants students from the space academy summer camps. The benefits to education and bringing more science to the masses would out-weigh the associated costs. Especially when you are penetrating households with very young kids. They soak up PBS and educational programming like little sponges. Mind you, if you don't get their attention early, they won't care nearly as much about these things later in life.

My solution: Put me in charge of NASA with the exact same funding it gets now. I'll grab a camcorder and interview employees and scientists, broadcast all the public domain educational media I can find, and work with colleges to get special assignments for students to help run the gig. It won't be Fox News, but it would be better than it is now. :)

name change by Lord+Dreamshaper · 2004-03-14 05:51 · Score: 2, Interesting

I'm all for including other deity names from other cultures, but for the sake of consistency, the new object (planet, comet, asteroid, whatever) should have a Roman name...it's not like there aren't enough objects elsewhere to be culturally sensitive...

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When all of your wishes have been granted, many of your dreams will be destroyed - Marilyn Manson

That would be 11th! by Vo0k · 2004-03-14 05:54 · Score: 2, Informative

Quaoar (though some claim it's too small for a planet...)

Alf predicted them both!

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Anagram("United States of America") == "Dine out, taste a Mac, fries"

Re:What, no more Roman gods? by meringuoid · 2004-03-14 06:06 · Score: 2, Insightful

The hypothetical tenth planet already has a name, assigned to it by common consensus of SF authors. It's Persephone, the bride of Pluto.

That said, my classical mythology is rusty: I think Persephone was the Roman one, daughter of Ceres, and Proserpina was the Greek one, daughter of Demeter - but I might be wrong. Time to inquire of the Overmind we call Google, methinks...

--
Real Daleks don't climb stairs - they level the building.

Umm...Mars? by 0x0d0a · 2004-03-14 06:06 · Score: 4, Insightful

don't know if anyone else feels this way, but I'm kind of let down by the fact that our most interesting space story for awhile now is that we MAY have a 10th planet in our solar system.

Umm...what? The past few months have been *spectacularly* exciting from a space point of view. We have two probes that successfully landed on Mars and have found strong evidence that Mars had liquid brine at one point. We have a ton of pictures from the surface to look at, and are expecting tons of findings, papers, and theories based on probe data that's been returned.

And while, yes, the classification may not be interesting, the fact that we discovered a new, sizeable chunk of matter in our solar system is not small stuff either.

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May we never see th

Re:What, no more Roman gods? by pajamacore · 2004-03-14 06:08 · Score: 4, Interesting

They might have chosen the name Sedna because the object is in the Kuiper Belt. If I recall correctly, the naming convention for Kuiper Belt Objects is that of creation deities. Sedna is the most important deity to the Inuit and plays a vital role in one creation tale, what with her parents chopping off her fingers and those fingers turning into various aquatic animals.

If I remember by bigattichouse · 2004-03-14 06:08 · Score: 3, Interesting

There was a formula for predicting orbital paths that was related to Fibbunaci's sequence, I wonder if sedna falls into the sequence?

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meh

Re:What, no more Roman gods? by eztcld · 2004-03-14 06:11 · Score: 2

Erm..wrong.
Plenty of minor greek deities left and
plenty of lesser known roman hand me down
divines of other than greek derivation.

Astrology = Syncretic Religion by handy_vandal · 2004-03-14 06:14 · Score: 4, Insightful

Still, at least this discovery has the redeeming quality of completely fucking up astrology.

Astrology doesn't work that way.

Astrology is syncretic religion -- it readily (and inevitably) incorporates new influences.

Like an amoeba, astrology engulfs everything it touches.

In this sense, astrology is rather like paranoia: everything pertains, everything is part of the Big Picture.

Sedna won't fuck up astrology. On the contrary, astrologers will eagerly seize on the idea of this new planet, treating Sedna as one more vacuole in the amoeba.

-kgj

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-kgj

Non-Roman? Okay, community protest time! by pla · 2004-03-14 06:15 · Score: 3, Insightful

Sedna? No. Plenty of people in this thread have complained about two facts - One, our planets have names derived from the Roman, not Inuit, panthon. And two, we already have a planet named after a sea-god, ie, Neptune.

So, I propose that in protest to such a blatant attempt at PC Multiculturalism, we as a community refer to the tenth planet as Nox, the Roman goddess of night. Since it lies the furthest from the sun, that actually fits it, in a descriptive sense.

Sedna... Whatever. Remember, we hear about this stuff months before your typical Fox news junkie, and people tend to respect us as sources of information. So spread the word - We have a new, tenth planet, named Nox. Sedna? Nope, they must have heard wrong. Nox. Nox? Nox!

I think Lectra would be a far better name... by bpd1069 · 2004-03-14 06:15 · Score: 3

for obvious reasons...

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on being a planet or something less... by joebeone · 2004-03-14 06:18 · Score: 5, Insightful

My former advisor here at UC Berkeley, Gibor Basri, has a neat way of discriminating between planets and the lesser (comets, asteroids, etc.). His idea is that if the object has enough self-gravity to force it into a spherical shape, it's a planet... if it doesn't (like Mars' "moons"), it's something less.

Here's a snipet:

How can this be resolved? A consensus is slowly developing (I believe) for the following solution. We can first define what we mean by "planetary mass", and base this only on physical characteristics. Then we can include circumstance into the definition of "planet". I propose the following three definitions:
FUSOR - an object that achieves core fusion during its lifetime.
PLANEMO - a round non-fusor.
PLANET - a planemo orbiting a fusor.
[...]

read on for his full article.

The following is a draft of an article now published in the Nov/Dec 2003 issue of Mercury. Draft of Mar. 20, 2003.

Defining "Planet" by Gibor Basri Univ. of California, Berkeley

Even before they were civilized, people looked into the sky and recognized different celestial objects. The Sun defined daytime, and the stars provided a fixed background of faint, twinkling lights at night. Among them moved the Moon, and a few special steadier lights. The Greeks called those which moved "planets" (it is worth noting that the Sun and Moon were originally included, since motion against the stars was the defining characteristic). Most cultures have an analogous word for these "wanderers". Both the stars and the planets were thought to revolve around the Earth.
After the Copernican Revolution, we recognize the Moon as the only body that orbits the Earth. The Sun is a very nearby example of a star, and the visible planets are other large bodies that orbit the Sun. We see them by reflected sunlight, while stars produce their own visible light. This understanding yields the dictionary (lay public) definition of the word "planet": a large heavenly body that shines by reflected light and orbits the Sun. In the past century we gained much understanding of our Solar System, and even visited most of the planets robotically. Yet today, professional astronomers find themselves unable to agree upon a succinct definition of "planet". Replacing "the Sun" with "a star" is obviously necessary now that many extrasolar planets have been discovered, but the problem goes well beyond that.
Two recent controversies that found their way to the popular press illustrate further difficulties. One is the "Pluto controversy". This arose because of the discovery of a large belt of icy objects beyond Neptune. They are the outer remains of the original protoplanetary disk. This "Kuiper Belt" is a natural outcome of incomplete planet formation in the outer Solar System, and is the source of some of the comets we see. As Kuiper Belt objects (KBOs) were discovered in increasing numbers in the 1990s, including a population of "Plutinos" which share Pluto's orbital characteristics (somewhat different from the other planets), some astronomers began to suggest that Pluto itself (which shares many properties with, but is the largest KBO known so far) does not qualify as a planet. The recent discoveries of Varuna and Quaoar (which are KBOs half the size of Pluto, like its moon Charon) may presage the time when we find another Pluto-sized KBO.
The current situation is much like that in the early 1800s, when the first asteroids were discovered. Ceres was originally hailed as the fifth planet, particularly since one in its position was expected from "Bode's Law" of planetary spacings. It lost its status within a few years, when other members of the asteroid belt began turning up. Herschel, who had been the only person to have discovered a new planet before then, aided the effort to demote Ceres. The arguments against its planeta

What about atmosphere? by Rick+the+Red · 2004-03-14 06:21 · Score: 4, Interesting

What we need is a simple rule: If it orbits a star and has an atmosphere, it's a planet. If not, it's not. I.e., things orbiting other planets are moons, even if they have an atmosphere. Things orbiting a star are asteroids (or whatever) if they don't have an atmosphere, no matter how large they are.

Pluto has an atmosphere, so it's a planet. What about Sedna? Does anyone know, or must we wait until Monday?

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If all this should have a reason, we would be the last to know.

Re:What about atmosphere? by beeplet · 2004-03-14 06:54 · Score: 4, Interesting

The presence/absence of an atmosphere is not as clear-cut as you might think... Both the moon and Mercury have comparably thin atmospheres. Are they both planets or both asteroids? Pluto may currently have an atmosphere, but it may freeze to the surface as the planet moves away from the sun. Will it cease to be a planet?

Re:What, no more Roman gods? by M1FCJ · 2004-03-14 06:29 · Score: 4, Funny

I feel insulted. I'm an atheist and I don't like these stupid god names polluting skies. What's the matter with these people? Can't humanity grow out of its infantile and get rid of this gods&belief nonsense?

Planet is not a useful category. by AlecC · 2004-03-14 06:30 · Score: 4, Interesting

The concept of Planets should no longer be regarded as a formal (as opposed to colloquial) classification. We have four rocky inners, four gassy outers, and a vast number of planetismals. Forming a group of the first two classes, with or without a few of the last, is a false classification.

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Consciousness is an illusion caused by an excess of self consciousness.

Re:Planet is not a useful category. by stwrtpj · 2004-03-14 13:48 · Score: 2, Funny

We have four rocky inners, four gassy outers, and a vast number of planetismals.
Jupiter: More beans, Mr. Saturn?

Saturn (waving its rings in Jupiter's direction): I'd say you had enough!

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Karma: Frotzed (mostly due to the Frobozz Magic Karma Company)

Picture of new planet: by big_groo · 2004-03-14 06:31 · Score: 5, Funny

Here----> .

Inuit Contributions by Vagary · 2004-03-14 06:34 · Score: 5, Informative

Hockey was invented somewhere in Europe or European North America in the 19th century. Lacrosse was invented by Indians near the St. Lawrence and is played on grass rather than snow, so I doubt the Inuit were involved.

Inuit inventions include snowshoes, toboggans, dogsleds, kayaks, toggle harpoons, and various other tools for hunting and travelling in the North as well as snow and ice civil engineering techniques. Pretty impressive, I'd say, for a culture with almost no wood, rock, or metal. They've probably contributed as much as any other non-Eurasian colonialised culture, and they make some really cool art.

This will be handy for sysadmins... by Boss,+Pointy+Haired · 2004-03-14 06:49 · Score: 3, Funny

This will be handy for those short-sighted sysadmin types that name their servers after finite sets like planets.

Now they'll be able to buy up to 10 servers before re-thinking their naming strategy.

Yeah, but by niom · 2004-03-14 06:53 · Score: 3, Insightful

what isn't pure gold to the conspiracy community?

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-- Repeat with me: "There is no right to profits".

Re:Yeah, but by daniel23 · 2004-03-14 08:56 · Score: 2, Funny

easy: pure gold.

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605413? Yes, it's a prime.

Rote Nonsense by fm6 · 2004-03-14 07:01 · Score: 2, Informative

That sort of rote memorization is stupid anyway. Sometimes you have to do it (like when you're learning the grammar or vocabulary of a foreign language). But making small kids memori8ze arbitrary, meaningless facts about a subject is a sure way to destroy their interest.

I've never had trouble remembering the names of the planets, and I totally suck at rote memorization. I just read some interesting stuff about them at an early age and it stuck.

In Sixth Grade, the teacher decided we all had to memorize the names of the presidents and recite them in class. I just couldn't do it. Interesting thing: the current president had just gotten re-elected, and everybody insisted on saying his name twice. I tried to point out that this didn't make sense, since nobody said "Roosevelt, Roosevelt, Roosevelt, Roosevelt". But I wasn't allowed to have an opinion, since I hadn't even done the assignment!

Re:revised planet mnemonics by konkani · 2004-03-14 07:14 · Score: 2, Funny

My Very Educated Mother Just Showed Us Nine Planets! Shucks!
My Very Extravagant Mother Just Sent Us Nine Parrots, Sweetheart
My Very Early Model Jaguar Just Smashed Up Near Pierre's Saloon

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please change me. - sig

Why Astrology Isn't Science by handy_vandal · 2004-03-14 07:21 · Score: 2, Insightful

[astrology] also doesn't work period :)

Agreed -- although I'll cut astrology some slack as a form of psychology, e.g. a collection of archetypes.

[Syncretic religion] Sorry, but: So would be Judaism, Christianity, et al. syncretic does not seem to involve active incorporation.
On the face of it, the more 'syncretic' a religion is, the more it was designed.
...Usually, IMHO, to be palatable to potential followers.

It's a question of degree ... some religions (e.g. astrology, vodoun) are strongly syncretic; others are somewhat syncretic (e.g. Christianity); some tend to resist syncresis (e.g. Islam -- the Koran exists *in Arabic*, thus cannot be "translated"), etc.

I can't think of a totally non-syncretic religion -- they all tend to incorporate -- nonetheless, it's a question of degree.

The predictions that involved the Zodiac cannot be both true now and at points in the past... [etc].

All good points. Personally, I have little or no use for astrology -- I'm not interested in defending its dogma, only in characterizing its role in society.

Oh, in fairness, without astrology we wouldn't have astronomy- or at least not nearly as much of it.

Just as modern chemistry owes a debt to alchemy.

-kgj

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-kgj

A decision based on Science, or Politics? by geoswan · 2004-03-14 07:32 · Score: 4, Interesting

Is this a decision based on Science? Or is it based on Politics and emotion?

Did you know that in 1998 Senator Patrick Leahy, of Vermont, got his State's largest Lake, Lake Champlain, to be reclassified as the 6th Great Lake? At least as far as the awarding of researh grants. Being considered a "Great Lake" made the academic institutions in his constituency eligible to apply for certain research grants.

There is talk of sending a probe to Pluto. Is it possible that it is easier to sell a probe to "planet Pluto" than to send one to Kuiper-belt object Pluto?

I remember, back in the days when I tuned in to debates as to which newsgroups should be created, the big debate as to whether a new group should be talk.acquaria, rec.acquaria or sci.acquaria.

In Leahy's defence, these were environmental research grants, and I should probably assume he added this line to the bill to protect his constituent's natural environment -- not for the petty partisan purposes.

Re:A decision based on Science, or Politics? by some+guy+I+know · 2004-03-14 21:46 · Score: 2, Insightful

I don't know what Dubya's camp is up to with all this space exploration/Mars stuff, but it just seems fishy to me.

First they spend (waste, IMO) billions sending probes to Mars (right after wasting millions or billions on a war) ...
As opposed to the previous administration, which didn't send any probes to Mars, and didn't spend any money on war?

(Note: I am not defending either Clinton or Bush on their war records; I'm just saying that you shouldn't dump on one without dumping on the other.
(My suggestion: Dump on both.))

--
Those who sacrifice security to condemn liberty deserve to repeat history or something. - Benjamin Santayana

naming convention by jd142 · 2004-03-14 07:45 · Score: 2, Interesting

Doesn't this violate the naming convention of using Roman god names for planets and then appropriate names for the moons. For example, Diemos and Phobos were children of Mars, Jupiter is surrounded by moons named for his lovers. Should this planet follow a similar convention and stick with a Roman god or goddess? Perhaps Proserpina, because she's close to Pluto (although really that would be an appropriate name for a moon if Pluto can grab a second one). Perhaps Janus, as god of doorways and bounderies would be appropriate to mark this orbit as the boundary of our solar system.

nomenclature by jrg · 2004-03-14 07:48 · Score: 2, Funny

don't these astronomers read lovecraft?

should this not be called, "yuggoth"?

Kuiper Belt Objects by nrlightfoot · 2004-03-14 07:54 · Score: 2, Interesting

This new ice ball is another Kuiper Belt Object (KBO), just like Pluto and all the other giant iceballs orbiting beyond Neptune that have been discovered lately. It is estimated that there are at least 70,000 of these objects with a diameter of greater than 100km. We only call Pluto a planet because it was discovered 20 years before the Kuiper Belt was theorized.

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what sig?

Escape velocity by geoswan · 2004-03-14 08:06 · Score: 4, Informative

Without their host planets, they would float off, wheareas the moon would continue orbiting the sun quite contently.

I have been interested in Astronomy since I was about six years old. Just over forty years. I have heard what you suggest before -- but only in the last few years. And I don't understand it any more this time than I did on the earlier occasions.

Frankly, I strongly suspect it is a false factoid, like that the internet was built to survive a Nuclear War. I strongly suspect it is a bullshit meme that keep being repeated because it sounds cool, but is completely false.

Pray explain what you mean when you say the other 138 moons would float off ?

I am trying to do the "thought experiment" of silently, quietly erasing the principals of those moons, mass and all. I am finding this difficult to do. I don't believe there is any way this could occur, in our Universe.

So, instead I imagined doing something to accelerate a moon, any moon, to the escape velocity of its principal. What happens then? Well, the object accelerated to just beyond a planet's escape velocity will assume an orbit very similar to that of the Planet it just escaped from. Sometime in the last couple of years ago there was a flap about a small object that seemed to have been temporarily captured in the Earth-Moon system. But it turned out to be NASA space debris. It appeared to be the discarded upper stage of an Apollo moon shot.

Re:Escape velocity by Doomdark · 2004-03-14 17:02 · Score: 3, Informative

false factoid, like that the internet was built to survive a Nuclear War.
Perhaps it's a typo from your part -- original Arpanet was certainly designed such that a network could be built that would survive effects of parts of network to be completed wiped out; something that could happen as a result of nuclear strike. I don't think Arpanet infrastructure itself was more than a (eventually large-scale) prototype (physically, I mean; protocols were certainly engineered correctly), and thus neither it, nor Internet later on, was built to be as tolerant as what protocols would allow.
That Arpanet was designed to survive catastrohic (yet not completely destructive -- there still has to be at least one route between nodes that want to communicate, obviously), is not an urban legend , and should be easily verified from various accounts by its creators.

--
I like paying taxes. With them I buy civilization -- Oliver Wendell Holmes
Re:Escape velocity by geoswan · 2004-03-15 01:31 · Score: 2, Interesting

I was fortunate enough to attend a very memorable and informative lecture, by Len Kleinrock, one of the creators of the Arpanet, in 1977. He spoke about the redundant paths, the ability to re-route, and so on, and the kinds of disasters they were meant to cope with. And that was things like back-hoe operators digging up communication cables, fires, power failures, rodents chewing through insulation. I also read the book, "Where Wizards stay up late: The origins of the Internet".
Yes, I am aware that a single highly speculative paper had been written, imagining a network that could survive a nuclear war. But, I believe, the guy who wrote it was not one of creators of the Arpanet. I specifically chose the word "built" as opposed to "designed" in anticipation of questions from those who heard an echo of this early paper.
The reason I mentioned this meme is that it is so entertaining that it is often repeated in the more entertaining form, that, "the internet was built to survive a nuclear war". I mentioned it as an example of an example where the falsehood has more power than the truth -- because it is entertaining.

Bode's Law by Gorimek · 2004-03-14 08:15 · Score: 4, Interesting

That would be Bode's Law. It is wiewed as more of a coincidence than a law these days.

According to my hung over calculations Sedna is 67 AUs out, which is not that far off from the 77.6 that Bode predicts, but not really close either.

The Inuit myth of Sedna by Futaba-chan · 2004-03-14 08:22 · Score: 4, Interesting

If I recall correctly, the naming convention for Kuiper Belt Objects is that of creation deities.

Sedna isn't actually a creator goddess -- she was born mortal, and became a goddess when the spirits of the air and the moon decided to reward her for her suffering in her mortal life, as she was drowning. Two accounts of the Sedna myth may be found here and here.

In any event, aren't you glad that they're naming it Sedna, and not Uinigumasuittuq?

Re:WTF, /. by Tony+Hoyle · 2004-03-14 08:27 · Score: 2, Insightful

An article like this is, admittedly, important, but its also something on the front page of EVERY NEWSPAPER WORLDWIDE.

What *have* you been smoking...

On the frontpage of every newspaper worldwide we have:

1. The carnage in spain + todays elections
2. The russian elections
3. Suicide bombers in israel (again)

The #1 science story on the bbc news is:

1. Fishing is harming albatross stocks.

Definately what is *not* #1 is

1. Some americans find a rock, call it a planet.

In fact I haven't been able to find *anywhere* that mentions this story except slashdot (confirmed by google news, which lists a single source for this story... slashdot).

Technically, the moon is a planet by MickLinux · 2004-03-14 08:47 · Score: 3, Interesting

The moon's orbit is everywhere concave towards the Sun. Therefore, the moon is a satellite of the Sun, and not a satellite of the earth. As such, perhaps it should be called a member of a binary planetary system.

--
Correct Horse Battery Staple: 72 bits of entropy. Enter "Correct H" into google. When it generates the phrase, that's

Re:Technically, the moon is a planet by jeisner · 2004-03-14 15:49 · Score: 4, Informative

The moon's orbit is everywhere concave towards the Sun. Therefore, the moon is a satellite of the Sun, and not a satellite of the earth. As such, perhaps it should be called a member of a binary planetary system.
Here are pictures and discussion of the moon's orbit about the sun.

Islam's Qur'an already predicted - 11 Planets! by deunan_k · 2004-03-14 08:51 · Score: 2, Interesting

Taken from this website - > Full Article

While you're at it, read this Article too regarding the eleven planets!

How many Planets - 9 ? or 11?

Ancient Greeks wrongly included head of the solar family and moon, our earths satellite. They counted planets as follows : 1) Sun, 2) Moon, 3) Mars, 4 ) Mercury, 5) Jupiter, 6) Venus and 7) Saturn. Indians till date include two more : Rahu and Ketu, mere shadows of earth and moon. To the five genuine planets modern astronomy added the Earth after being (identified with planet class in the medieval age) and latest discoveries of Neptune, Uranus and Pluto (as late as 19th century). This brought back the count to 9.

This received a jolt a decade or two ago. Indian astronomer J.J Rawal in 1978 found that the farthest planets Uranus and Pluto were making significant deviations from established orbits and explained them in terms of gravitational influence of two as - yet unseen planets, whose sizes and orbits he estimated. It was only in 1988 his proposal got due publicity when NASA confirmed possibility of Rawals outermost planet (or the 11th), by analysing their own data gathered through their various space missions. NASAs computations of mass and orbit tallied with Rawals with refinements and additional details. Nevertheless, NASA could not guess his 10th planet. Early this year (1999) NASA brought the 11th planet to the limelight again among astronomical community and general public. However, both the planets of Rawals still remain unconfirmed optically.

Has Quran anything to say about the number of solar planets? Yes, indeed!

When Joseph said unto his father : O my father! Surely I saw in a dream eleven planets and the Sun and the Moon....... (Yusuf: 4)

One may note the following points of immense significance.

* Quran does not confuse the planets (kawakib) with stars (nujm).

* Quran excludes Sun and Moon clearly from planets. They belong to a higher and lower order respectively. Such clear demarcation was achieved only by modern astronomy which is but a few centuries old.

* The number of planets are given as 11. We mumins have absolutely no doubt that it is a matter of time that modern astronomy will reach this count. Science is now in the process of gathering evidence for what it has already made indications.

Incidentally, when in 1988 news of NASAs findings broke out concerning Rawals prediction of two extra planets this author published an article titled New Planet Discovered - As Prophesied by The Quran? In Islamic Voice (March, 1988) quoting this Quranic verse now under discussion. He sent a copy to the astronomer which reached him exactly on the day he returned from lecture tour from US. On the very same day he wrote back expressing his amazement at the Quranic prophecy and remarked that he would thenceforth quote the particular verse whenever he lectured on his discovery.

The author would also like to express his regrets that many translators of Quran in English as well as languages use the word stars in this verse instead of planets which Allah specifies. They are either unable to distinguish between these two different classes of heavenly bodies or are under the mistaken impression that planets are merely a subclass of stars or vice-versa.

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Will sys-admin for food

Full Details... by Anonymous Coward · 2004-03-14 09:27 · Score: 2, Informative

http://www.gps.caltech.edu/~chad/2004dw/

"Sedna"? by xihr · 2004-03-14 09:49 · Score: 2, Interesting

The name is unofficial -- it takes a while for the IAU to grant official names to asteroids -- and just because it's sizeable (larger than Charon, but smaller than Pluto) doesn't mean it's sparking new controversy over whether it's a planet or not. Practically the only "controversy" about planethood that's ever taken place is among the media and amateurs. Professional astronomers have rarely cared over the details of whether you call Pluto (say) a planet or not; they know that the nomenclature was invented by humans and so the celestial bodies themselves don't feel any compulsion to fit into our little arbitrary lines of demarcation.

Re:Non-Roman? Okay, community protest time! by galen · 2004-03-14 12:00 · Score: 2, Insightful

(e.g. Ceres, which is an obscure Roman name)

An obscure Roman name? You've got to be kidding me. In the ancient pantheon, Ceres/Demeter was the goddess of fertility and agriculture. In other words, she was the mother goddess. Every year she mourns for her lost daughter Persephone and forsakes her duty. During this period all living things on the earth wither and die; thus we have winter.

If such an important goddess has really become "obscure" then maybe I'll go into mourning, though I doubt anyone will notice.

~~Galen~~

I, for one... by zaba · 2004-03-14 12:40 · Score: 2, Funny

yada yada yada welcome our overlords blah blah blah sedna.

Did I forget anything from the ObSimpsons quote?

Quaoar by Krellan · 2004-03-14 15:35 · Score: 2, Informative

This reminds me of Quaoar.

Both are small Kuiper Belt objects. Quaoar was mentioned on Slashdot before.

It's nice to find these mini-planets and give them names. The area beyond Pluto is fascinating, all the more reason why the New Horizons probe should be launched. I hope that Bush's single-minded fixation on Mars doesn't cause this project to be scrapped....

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Dr. Demento On The 'Net!

Size doesn't matter by kkerwin · 2004-03-14 16:02 · Score: 2, Informative

Perhaps, to avoid all possible arbitrariness as you say, a new standard should be proposed.

Instead of measuring the distance across an object, as this seems to lead to some problems in our definition, perhaps we should look at it's mass, in respect to the force of gravity between it and our sun.

Newton came up with a very simple equation to figure this out:

f = GMm/r^2

Where f is the force of gravitation between the two objects; G is the universal gravitation constant, 6.67 * 10^-11 Newton*Meters^2/kg^2; M is the mass of our sun; m is the mass of the object in question, and r is the (average) distance between the two.

The smaller the force of gravitation, the less likely that object is to become captured within the sun's gravitational pull. By setting a limit on how low f may drop before the object is no longer considered a planet, we very clearly define what may be considered a planet, what an asteroid, and what just space junk.

This throws into question not relative size, or diameter of the planet, but rather it's average density in respect to the density of our sun, and the distance between the two; ie, the force of gravity between the object and our sun.

Google for universal gravitation for more specifics.

- Kris Kerwin

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Kris Kerwin kkerwin@insi__REMOVE_ME__ghtbb.com

Here, a rule that I propose.. planet versus other: by deathcow · 2004-03-14 18:00 · Score: 5, Interesting

If it's big enough to assume spherical shape by the action of gravity, it's a planet.

Re:Here, a rule that I propose.. planet versus oth by daeley · 2004-03-14 18:29 · Score: 5, Funny

By that logic, Anna Nicole Smith qualifies. ;)

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I watched C-beams glitter in the dark near the Tannhauser gate.

Get to the asteroid sooner. by DunbarTheInept · 2004-03-14 19:38 · Score: 4, Informative

The key to preventing an extinction-causing asteroid impact is simply to NOTICE it early enough and have a fast means to get a vehicle there. The reason the asteroid-defeating plans are so hard to create is that we have to wait until the asteroid is near us before we can reach it. By then it's too late. If we can affect it sooner, then exploding it into parts could work really well because the parts would be imparted with enough velocity to spread apart so most of them miss the Earth. Even if an object is headed to strike the earth dead-center, then you only need to deflect it far enough to move it a little more than one earth-radius of distance to the side by the time it gets here and that will make it miss.
(You do need to go a little more than one earth radius because gravity will pull it in - you need to get it far enough out so it will at least slingshot around earth instead of striking it.)

To put this in perspective, if the asteroid was blown up 40 days before impact, that would give us 960 hours for it to move. In 960 hours, an object can move an entire earth radius by going a mere 4.1 miles per hour. So as long as the explosion can impart a velocity of a little over 4.1 miles per hour perpendicular to the course of the asteroid, then the asteroid bits will veer far enough off course to miss. So exploding the asteroid and sending it's parts off in different directions *can* work, if your explosion is big enough to impart that much velocity, and (this is the hard part) you can get a vehicle carrying the bomb out there 40 days before the impacyt.)

The best defense against such an asteroid is a better space program, with faster vehicles that don't require months of prep time to launch. That gives us the time for a simple solution to actually work.

--

Don't label something "offtopic" unless you know the topic well enough to tell what's on topic.

Re:Here, a rule that I propose.. planet versus oth by Anonymous Coward · 2004-03-14 20:39 · Score: 2, Interesting

Aren't Ceres and Vesta both gravitaionally spherical(ish)

You should also include that the body is massive enought to reatin some form of atmosphere. Pluto and Mercury manage this, the asteroids don't as far as I am aware.
Andy

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The Sun's 10th Planet... Sedna?

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