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Astronomers Spot Most Distant Object In the Solar System (sciencemag.org)

Posted by Soulskill on from the wonder-if-it-has-oil dept.

sciencehabit writes: Astronomers have found the most distant known object in our solar system, three times farther away than Pluto. The dwarf planet, which has been designated v774104, is between 500 and 1000 kilometers across. It will take another year before scientists pin down its orbit, but it could end up joining an emerging class of extreme solar system objects whose strange orbits point to the hypothetical influence of rogue planets or nearby stars. In other planetary science news, UCLA professor Jean-Luc Margot has proposed a new definition of the term "planet" which would allow for the inclusion of exoplanets. His metric is laid out in an academic paper available at the arXiv.

85 comments

  1. i identify as a planet by turkeydance · · Score: 5, Funny

    and i demand to be treated as one.

    1. Re: i identify as a planet by Anonymous Coward · · Score: 5, Funny

      You were born a moon and, by God, you'll act like it! And enough of this filthy talk of astroid drilling, it's unnatural!

    2. Re:i identify as a planet by Anonymous Coward · · Score: 0

      Yo momma so big she identifies as a planet too

    3. Re: i identify as a planet by Anonymous Coward · · Score: 0

      My momma is such a big person she doesn't give a crap about the definition of the word "planet".

    4. Re:i identify as a planet by Maritz · · Score: 3, Funny

      Clear out your orbit and we'll talk.

      --
      I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
    5. Re: i identify as a planet by JaredOfEuropa · · Score: 1

      Is "planet" the new "big-boned"?

      --
      If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
    6. Re:i identify as a planet by Anonymous Coward · · Score: 0

      Dude, don't egg him on. You got to assume a poster with a name of turkeydance is at least 6' 5", 300+ lbs., drives a big effin truck, and likes to drink. Ain't nothing wrong with any of that, I just don't think it's wise to encourage such a person to be clearing out their path is all.

    7. Re: i identify as a planet by Anonymous Coward · · Score: 1

      I'm often persecuted for having an eccentric orbit.

    8. Re: i identify as a planet by Anonymous Coward · · Score: 0

      When may I start drilling into you?

    9. Re:i identify as a planet by Impy+the+Impiuos+Imp · · Score: 1

      Is this part of the anti fat shaming movement?

      --
      (-1: Post disagrees with my already-settled worldview) is not a valid mod option.
    10. Re:i identify as a planet by Anonymous Coward · · Score: 0

      Are you saying that your face looks like Uranus?

    11. Re:i identify as a planet by Anonymous Coward · · Score: 0

      As everybody knows, beer is an essential catalyst in the process of planet formation.

    12. Re:i identify as a planet by Scarletdown · · Score: 1

      You could probably make big bucks following him around with a tuba.

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      This space unintentionally left blank.
    13. Re:i identify as a planet by Scarletdown · · Score: 1

      2620 can't come soon enough.

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      This space unintentionally left blank.
    14. Re: i identify as a planet by scum-e-bag · · Score: 1

      That's no moon...

      --
      Does it go on forever?
    15. Re: i identify as a planet by Anonymous Coward · · Score: 0

      Close. It's spelt "Moron".

    16. Re:i identify as a planet by Pseudonym · · Score: 1

      You can't be a planet, which is nobody's fault, not even the IAU. But we will fight the oppressors for your right to be a planet.

      --
      sub f{($f)=@_;print"$f(q{$f});";}f(q{sub f{($f)=@_;print"$f(q{$f});";}f});
    17. Re:i identify as a planet by Anonymous Coward · · Score: 0

      Hey, I resemble that remark!!

    18. Re:i identify as a planet by Tablizer · · Score: 1

      Must...Resist...Chris...Christie...Jokes

      --
      Table-ized A.I.
  2. Does this mean??! by wkwilley2 · · Score: 1

    We can have Pluto again?

    --
    Have you ever fallen asleep at the keybhanusdiog?
    1. Re:Does this mean??! by Anonymous Coward · · Score: 0

      You still have Pluto. It's a Dwarf Planet.

    2. Re:Does this mean??! by Rei · · Score: 2, Insightful

      Nope. A tiny fraction of a group who is overwhelmingly not planetary scientists has spoken and made their internally-inconsistent definition. It stands until they revoke or alter it.

      --
      The yellowcake is a lie.
    3. Re: Does this mean??! by Anonymous Coward · · Score: 0

      Except a tiny fraction of planetary scientists actually disagree with the classification of Pluto. You can whine and use hyperbolie about the vote all you want, but the outcome wouldn't have changed unless you took a vote with a much more specific, stacked minority. There are some complaints about the exact wording definition that might have been better addressed, but it would not have changed the situation for Pluto, considering every call for a more precise numeric metric showed orders of magnitude gap between it and other larger bodies in the solar system.

    4. Re:Does this mean??! by Anonymous Coward · · Score: 0

      The attitude that scientists should waste so much more time on the names of things is potentially more damaging than any crummy naming scheme. Most astronomers are too busy doing actual work to care, and its sad that people care more about the name of something than the actual work, properties, and essence of that actual thing.

    5. Re: Does this mean??! by Rei · · Score: 3, Informative

      Except a tiny fraction of planetary scientists actually disagree with the classification of Pluto.

      In the words of Wikipedia, "Citation needed". The planetary scientists at the IAU meeting had been by and large pursuing a definition involving a body reaching gravitational equilibrium. They've also been leading the charge to get it overturned. There are numerous published papers by planetary scientists who continue to refer to large KBOs and the like as planets. The New Horizons team is particularly notable in continued references to them as planets.

      The vote passed via a non-randomly-selected 4% of the IAU's membership who were - as previously mentioned - overwhelmingly not planetary scientists. Letting people who study stars (by the way, a "dwarf star" is still a "star") decide what a planet is is just plain stupid - it's not their field of expertise. The first draft proposal indeed went with the planetary scientists' version - hydrostatic equilibrium being the criteria, and was confirmed on the 18th, with intent to vote on the 24th. Many people left the IAU meeting thinking that this was the version that was going to be voted on, and since they supported either having it or no definition at all, they didn't need to be there. The proposal was changed however on the 22nd. Due to dischord among the IAU members there were "secret" negotiations held on the proposal on the evening of the 23rd, and it looked increasingly unlikely that anything was going to be agreed upon. But then they came out with the current version on the 24th - after most of the membership had left - and had it voted on during the same day, when most of the people remaining were the ones who had been fighting against the planetary scientists' equilibrium definition. They furthermore reverted the standard rules which only allow people in a specific field to vote on matters related to their field, declaring the definition of planet a matter applicable to the whole union, so that everyone, not just planetary scientists, could vote.

      There are not little complaints about "the exact wording" - do I really need to go into a breakdown of all of the arguments against it?

      --
      The yellowcake is a lie.
    6. Re: Does this mean??! by Anonymous Coward · · Score: 1, Insightful

      There are not little complaints about "the exact wording" - do I really need to go into a breakdown of all of the arguments against it?

      No, but if you are going to demand citation from others about what the majority of planetary scientists think, you can't conveniently ignore that yourself.

      Do you have any citation that the vote was not representative, and that it would have changed the status of Pluto if any of that stuff you complain about was different? And finding a few planetary scientists that are upset about the definition is not the same as saying a majority care to vote for/against it.

      It doesn't matter how quirky the voting was or not if it wouldn't have made any difference. Whatever arguments you have doesn't change how the planetary scientists or IAU at large would have voted either if you removed some of those common quirks in the vote.

      So yeah, as you said, citation needed...

    7. Re: Does this mean??! by Rei · · Score: 3, Interesting

      I described the process that led up to the vote, which you can easily read anywhere on the net. You can also readily find no shortage of planetary scientists complaining about it on the net. If there's any specific fact you disagree with, state it and I will reference it for you.

      --
      The yellowcake is a lie.
    8. Re: Does this mean??! by Anonymous Coward · · Score: 0

      There are not little complaints about "the exact wording" - do I really need to go into a breakdown of all of the arguments against it?

      Considering there are and were several alternative proposals that involved what crossed the orbit of the planet, yes, there were complaints about the exact wording but still amount to a similar definition. Whatever arguments you have for or against a particular definition has no relevance to the existence of those other proposals and that some astronomers were debating over the wording instead of general principle.

    9. Re: Does this mean??! by Anonymous Coward · · Score: 0

      (by the way, a "dwarf star" is still a "star")

      Yet a dwarf nova is not a classical nova...

    10. Re: Does this mean??! by Anonymous Coward · · Score: 0

      I think the IAU definition of planet is stupid, but I also think pretty much 99% of the argument about the definition on the internet is stupid too. The modding of the above posts just demonstrates how much of this is just a popularity contest.

      Someone asks for citation that a majority of astronomers agree with the definition but gives none of his own that a majority disagree? +5

      Someone asks for a citation that astronomers disagree and points out that still no citation has been provided? -1

    11. Re: Does this mean??! by Anonymous Coward · · Score: 0

      Umm, you're still not giving any citation or evidence that the majority of astronomers, planetary or otherwise, disagree...

    12. Re: Does this mean??! by Anonymous Coward · · Score: 0

      That's the "Science!" crowd for you.
       
      It's not that I disagree with Rei or have anyway to offset anything he may have said, he seems to know his stuff, but the argument is stupid on its face.
       
      Call Pluto anything you want. The only reason that it's such a sore spot for anyone outside of the IAU is because NdT rides it like a trophy horse. Even as much as the man claimed he wouldn't drone on about it anymore he still did drone on about it for 20 minutes during his last tour.
       
      I know a few members of the IAU. None of them were at the vote for this. None of them seem to care either. Being emotionally invested in this kind of jibberjabber without having a real stake in the matter is foolishness.
       
      Just a FYI: This is my first post on the thread. It bothers me more than people compare NdT to Carl Sagan than it does to have Pluto called a dwarf planet. It's time to move on.

    13. Re: Does this mean??! by Anonymous Coward · · Score: 0

      The vote passed via a non-randomly-selected 4% of the IAU's membership who were - as previously mentioned - overwhelmingly not planetary scientists.

      So... why don't they just vote again? If someone is using bylaws to block that, why don't they organize and write organized letters that lets you count the number of signatures of IAU members who disagree? Just posting randomly to blogs or mentioning something in an interview gives no sense of how many astronomers actually care. You can't tell if it is a wide spread concern, or a personal vendetta.

      I am not in the IAU, but I am in a couple other societies/unions for physical sciences. They all have their own internal politics, and each one has had at least one situation where something was not fairly voted upon (often something just done by the organization executives, with no vote at all). (Re)Votes were brought up again at later meetings, even when it turned out the people complaining were a very small minority. Before those votes, or when they were blocked, there were official complaint letters that were signed by members, published online and in the relevant newsletters.

      In every case I've seen in similar organizations where it came down to an unfair vote (or even fair votes that some subset felt were unfair), the opponents easily could make their numbers known. And numbers is the key word, because when complaining about votes being unfair, that is what you're talking about. It doesn't matter how good or bad the arguments are for each side, if someone thinks a voting process was a key step in messing things up, then the critical counter is to show that their are large enough number of people that indeed the vote turned out the wrong way.

      So, does anyone have any insight into what has been done in this case along those lines?

    14. Re:Does this mean??! by Anonymous Coward · · Score: 0

      So is a brown dwarf also a planet?

    15. Re: Does this mean??! by Anonymous Coward · · Score: 0

      : (by the way, a "dwarf star" is still a "star")

      But a "Brown Dwarf" is NOT a *star*

      Yet, brown dwarfs share features with the coolest red dwarfs and with planets. And for all the claims that these other objects are "planets", there are many moons in the Solar System that have these same features, yet planetary scientists are not calling for them to be called planets. If they wanted to stick to their field, they would ignore the fact that moons orbit planets, and instead call them planets as well. But they don't. Clearly they are not being consistent.

      Clearing their orbital zone is a reasonable criterion, unless you want to include moons as planets, and ignore all orbital characteristics. If your basis is hydrostatic equilibrium, then there is no reason to exlcude moons.

    16. Re: Does this mean??! by RubberDogBone · · Score: 1

      But none of this matters. No matter what humans call Pluto or how we classify it. whether we fight wars about it on /. or on a battlefield with guns, none of this matters whatsoever to the astronomical object we call Pluto. Every single atom it's made of will carry on the same regardless of what we call it, or whether indeed humans had ever managed to find out it was there at all.

      So go on and argue about it. Someone will eventually win. And it will still make no difference at all. Pluto will carry on for billions of years after humanity has vanished from this universe. If life exists or develops on another body in the Sol system, perhaps Pluto will even get a new name which will also matter not at all.

      --
      Sig for hire.
    17. Re:Does this mean??! by Anonymous Coward · · Score: 0

      Nope, there is just eight planets in the universe.

    18. Re: Does this mean??! by Anonymous Coward · · Score: 0

      And it will still make no difference at all. Pluto will carry on for billions of years after humanity has vanished from this universe. If life exists or develops on another body in the Sol system, perhaps Pluto will even get a new name which will also matter not at all.

      Even way before that, it makes no difference to most astronomers, including planetary ones. They will continue to study the same objects, do the same observations, publish papers, they just might have to change their wording from time to time.

    19. Re: Does this mean??! by Anonymous Coward · · Score: 0

      But none of this matters. No matter what humans call Pluto or how we classify it. whether we fight wars about it on /. or on a battlefield with guns, none of this matters whatsoever to the astronomical object we call Pluto. Every single atom it's made of will carry on the same regardless of what we call it, or whether indeed humans had ever managed to find out it was there at all.

      So go on and argue about it. Someone will eventually win. And it will still make no difference at all. Pluto will carry on for billions of years after humanity has vanished from this universe. If life exists or develops on another body in the Sol system, perhaps Pluto will even get a new name which will also matter not at all.

      Intersting point.

      New plan guys, lets' make Pluto a planet by force.
      You all go gather a bunch of comets to pile up on Pluto, I'll start looking for a way to knock Neptune into the Sun.

    20. Re: Does this mean??! by Anonymous Coward · · Score: 0

      The only bodies worthy of being called "planets" are those discovered by European astronomers, members of the European Master Race. Anything seen by mongrel americans and jewish science is not. It is settled. Heil! Heil! SIEG HEIL!

    21. Re: Does this mean??! by adhdengineer · · Score: 1

      why not just start their own IAU? with blackjack! and hookers!

  3. It's so ridiculously easy by Rei · · Score: 3, Insightful

    .. to make up a formula to say what you want it to say for data like this.

    Here, want an alternative formula to declare the 8 IAU "planets" as planets as well as exoplanets but exclude the IAU "dwarf planets", without using any of the terms he uses, and to be able to classify 100% (rather than the 99%) of exoplanets?

    MeanDistanceFromTheSun / DiscoveryYear ^5 > 0.21mm/y^5

    It's a functional formula. Does this mean that it's a reasonable formula? Of course not; it has no connection with the reality of what they actually are. But you know what? Neither does his or the IAU's "cleared the neighborhood" concept. There are no credible planetary models that show for example that Mars cleared its own neighborhood. While they differ on the details, they all agree that Jupiter cleared it (and cleared most of the debris from the inner solar system in general, with some help from Saturn). Neptune has (despite its distance from the sun) orders of magnitude more orbit-clearing power than Mars yet nonetheless contains multiple objects a couple percent the size of Mars in its "neighborhood". Is Mars not a "planet"?

    I have a giant list of reasons why the IAU decision is poor and unscientific, but no need to post it again.

    --
    The yellowcake is a lie.
    1. Re: It's so ridiculously easy by Anonymous Coward · · Score: 0

      Yes, it is easy to find a arbitrary formulas for grouping like that. But that is irrelevant. What matters is it is much more difficult to develop any formula that has some relevance to planetary dynamics which doesn't make Pluto look like an outcast, and that is the problem. I've seen enough talks on simulations of orbit stability and dynamics, and every metric derived to show how much a planet can scatter stuff out of its orbit results in a huge gap between Pluto and the other eight. Jupiter may be involved in cleaning out many orbits, but simulations show Mars is more than capable of doing so on its own. Just because you label something as unscientific doesn't make it so, especially when your own claims disagree with research.

    2. Re:It's so ridiculously easy by Anonymous Coward · · Score: 0

      It doesn't matter if the definition is scientific or not, but about how useful it is in scientific literature (which usually involves some scientific bases anyway though). The changing the definition doesn't force theories to change, only changes how many words are needed to use when listing things out for discussions of said theories. Defining categories out of convenience is quite common, especially once you look at something other than say binomial nomenclature in biology. Just look at how much junk in geology is defined based on how easy it is to find in a specific area as opposed to the relationships between rock in different areas (but there are categories for that too).

      If someone comes up with an actual meaningful need for a different categorization, then things can be changed or a new category system can be made, as nothing prevents multiple category systems in something as complex as many fields of science.

      Your formula fails because it is pretty much useless in reference to any science communication. Now how easily can you come up with a formula which includes Pluto and actually is noticeably more useful in astronomy literature to make a difference? That is what matters, as opposed to discussing how much useless examples you can come up with. E.g. one can come up with many different ways of arranging a table of elements that are useless, but that doesn't say anything about how useful or useless that most common table of elements arrangement is.

    3. Re:It's so ridiculously easy by Anonymous Coward · · Score: 2, Funny

      You seem obsessed over something most people don't care about and are able to back it up.

      I like you.

    4. Re:It's so ridiculously easy by khallow · · Score: 1

      If someone comes up with an actual meaningful need for a different categorization

      Even in 2006, over a hundred exoplanets had already been discovered. That is the meaningful need which was already present for a definition that only applied to Solar System objects.

      Another reason the prior formula fails is that it includes data dependent on the observer. Suddenly, it matters when you made the observation, which is an absurd thing to do.

      I like the proposed definition because it is dependent on relatively easy to determine observables of an exoplanet and its star.

    5. Re:It's so ridiculously easy by Anonymous Coward · · Score: 0

      Even in 2006, over a hundred exoplanets had already been discovered. That is the meaningful need which was already present for a definition that only applied to Solar System objects.

      Making the definition specific to our solar system was on purpose, because there was expectations of huge biases in what exoplanets we can observe so far, so it was best to leave that to a later date. And I don't see much need in current literature for a specific definition, as observations are not quite to the point of uncovering large grey areas that need an actual precise definition to clarify.

      I like the proposed definition because it is dependent on relatively easy to determine observables of an exoplanet and its star.

      Nonetheless, easy to define proposals don't hurt too much to accept if they can be changed later if the need arises. Of course changing such things seems to create a lot of butthurt on the internet, but that isn't a priority concern among astronomers when defining jargon.

    6. Re:It's so ridiculously easy by Anonymous Coward · · Score: 0

      I have a giant list of reasons why the IAU decision is poor and unscientific, but no need to post it again.

      There is no need to post it, because every such debate on the internet comes down to a popularity contest and self-rationalization on both sides. Both sides think the other is being unscientific, and think that declaring such makes themselves right.

      Whether it is the mods on Slashdot or shared Facebook posts, or attention grabbing in interviews with a small minority of relevant researchers, it all amounts to amassing a huge amount of attention on something that makes virtually no difference in the actual science. That seems to be a much bigger problem, that people fail to recognize what actually matters in science research. That people take the time to post a "giant list" on such pointless battle and think it means something is a sad waste.

    7. Re: It's so ridiculously easy by Rei · · Score: 3, Interesting

      but simulations show Mars is more than capable of doing so on its own

      Mars has a tiny fraction the Stern-Levison parameter of Neptune, and Neptune hasn't gotten rid of large bodies from its "neighborhood" (they're small compared to Neptune, but not compared to Mars).

      What matters is it is much more difficult to develop any formula that has some relevance to planetary dynamics which doesn't make Pluto look like an outcast, and that is the problem.

      It's not a "problem" at all. The definition that most planetary scientists wanted the IAU to choose (if they felt the need to pick one at all) was hydrostatic equilibrium, meaning there would be dozens of planets. Achieving a rough hydrostatic equilibrium is a very meaningful dividing line - it means differentiation, mineralization processes, alteration of primordial materials, and so forth. It's also often associated with internal heat and, increasingly as we're realizing, a common association with subsurface fluids. In short, a body in a category of "not having achieved hydrostatic equilibrium" describes a body which one would study to learn about the origins of our solar system, while a body in a category of "having achieved hydrostatic equilibrium" describes a body one would study, for example, to learn more about tectonics, geochemistry, (potentially) biology, etc. By contrast, a dividing line of "clearing its neighborhood" - which isn't actually what half of the planets in our solar system have done - says little about the body itself.

      And yes, there are many reasons why the whole process was grossly unscientific. I've first already covered the voting process above, which is absurd, especially in a day where they could have handled such a thing online. There's the obvious criticism of it being sun-centered, having no clear definition on what defines a "neighborhood" or "cleared", the pseudoscience of the planets all having cleared their own neighborhoods, the lie about how they planned to review further "dwarf planets" for inclusion (they haven't), the comparative inconsistency (really, Earth is more like Jupiter than it is like Pluto?), the atrocious name where a "dwarf X" isn't an "X", and on and on. But these are just minor points.

      First off, the primary reason cited by virtually every scientist I've seen interviewed about their vote in favor of an exclusive standard over an inclusive standard is along the lines of, "It would be too hard for schoolchildren to memorize the names of all of them". This is such a blatantly unscientific standard that it doesn't even bear going into, and leads to absurd consequences when applied to other fields, such as the AMA declaring that there's only 8 bones in the human body and all others are "dwarf bones" that aren't real bones, or the USGS declaring that there's only 8 rivers in the world and all others are "dwarf rivers" that aren't real rivers, all for the purpose of making things easier for students to memorize. They decided that they wanted schoolchildren to be able to memorize the names of all the planets around the sun, and then contrived a definition of "planet" to try to make that happen. This is not science, it's idiocy.

      Then there's the basic issue of scientific categorizations altogether. In every scientific field, the universe continually presents those making discoveries with a wide range of diversity. This is almost universally accepted in an inclusive manner, subdividing groups into subgroups, and subdividing those further. We will continue to find new types of planetary bodies in a wide range of diversity - large terrestrial planets, dwarf-scale planets, gas giants, ice giants, hot jupiters, super-earths, water worlds, supercomets, extremely large bodies orbiting as moons, planets without parent stars, and so forth. Rather than trying to hide diversity, science is supposed to embrace it.

      Then there's the issue of the timing. For most of the history of humankind's knowledge of Ceres and Pluto, we have

      --
      The yellowcake is a lie.
    8. Re:It's so ridiculously easy by khallow · · Score: 1

      Making the definition specific to our solar system was on purpose,

      So what? My argument is still valid. They could have just kicked the can down the road.

      Nonetheless, easy to define proposals don't hurt too much to accept if they can be changed later if the need arises. Of course changing such things seems to create a lot of butthurt on the internet, but that isn't a priority concern among astronomers when defining jargon.

      It caused a lot of "butthurt" because the definition was unscientific and unwarranted.

    9. Re: It's so ridiculously easy by Anonymous Coward · · Score: 0

      Mars has a tiny fraction the Stern-Levison parameter of Neptune, and Neptune hasn't gotten rid of large bodies from its "neighborhood" (they're small compared to Neptune, but not compared to Mars).

      Except the relative size of bodies is entirely relevant. Just sweeping it away and trying to pretend it doesn't matter is just self-rationalization on your part, and ignores the basis of simulation work that underlies things like the Stern-Levison parameter.

      which isn't actually what half of the planets in our solar system have done - says little about the body itself.

      Again, you're just trying to self-rationalize by redefining what it means to clear the neighbourhood, when things like the Stern-Levison parameter make it rather quite clear.

      Additionally, all of your talk about the significance of hydrostatic equilibrium is geology centric. Should the definition of planet be based on more geology relevant terms or on planetary body dynamics terms? There is no "right" answer to this, and pretending that what is important to one subfield is somehow more scientific right than what is important to another is disingenuous at best. There is nothing wrong with having multiple classification schemes when different subfields have interest in different parameters. But deciding who ends up using older, vague terms and who gets new categories ends up being rather arbitrary then, and not something you can claim is scientific one way but not the other.

      Making scientific declarations about objects that you know little about when vast amounts of data are coming in the pipeline for the very first time - data that could influence members making the decision about whether hydrostatic equilibrium is more meaningful than the objects' "neighborhood" - is profoundly unscientific.

      And yet nothing that was seen has changed the debate, as people who are interested in the neighbourhood around a planet are still interested in that, and those that are more interested in the internal dynamics of a body are still interested in that. What could they possibly have found that would have changed people's opinion or preference for their own line of work? How is that in any way related to what is scientific or not when deciding whether the name should apply to what is important in one field vs. another?

      over what is a scientific truth

      Except this debate has nothing to do with what is scientific truth. Names don't change that. It is purely a human construct how we group things, and that will never change the properties and significance of research of any members of those categories. Claiming the categorization is debate over a scientific truth fundamentally misunderstands what a scientific truth is.

      Anyone who spends any time looking at any of the internet commentary on the dwarf planet decision will find them full of comments along the lines of "Scientists can't even agree about whether Pluto is a planet, why should we trust them about global warming?" I wish this were hyperbole, but I've seen it far too often to ignore .

      Yeah, and there are also lots of people saying, "I don't care what scientists say, I will believe X," and others arguing over things that have little to do with science. So I guess science categorization should be dictated by appeal to public popularity then? Do you think any amount of science rationalizations of the definition mattered one way, when all people cared about was that Pluto be called a planet? Speaking of unscientific...

      A lot of damage from such debate seems to come from people trying to misappropriate what is "scientific" vs. not to bolster their side, and making the public think this is actually the most important issue in planetary science. No matter how bad of a definition was declared, the situation is made far worse by those who think it should get far more attention than actual research, insisting that such things actually can have massive impacts on the work in a field. It is bad enough when people politicize science to argue something, but it is particularly sad when it is done in a way to aggrandize such an insignificant mess.

    10. Re:It's so ridiculously easy by Anonymous Coward · · Score: 0

      They could have just kicked the can down the road.

      That is exactly what they did... they said lets make something useful to planetary scientists working in the solar system, and come back again when we need to do something applicable to exoplanets.

      It caused a lot of "butthurt" because the definition was unscientific and unwarranted.

      No, the vast majority of the butthurt was because Pluto was no longer a planet, and had nothing to do whether it was scientific or not to call Pluto a planet. You could have had the most elegant, scientific definition ever, but if it changed the status of Pluto, the vast majority of the people would be bitching the same, because they didn't even care about the details of the actual definition.

    11. Re: It's so ridiculously easy by Anonymous Coward · · Score: 0

      Mars has a tiny fraction the Stern-Levison parameter of Neptune, and Neptune hasn't gotten rid of large bodies from its "neighborhood" (they're small compared to Neptune, but not compared to Mars).

      You're misunderstanding the significance of the Stern-Levison parameter. It determines how likely planets are to scatter other, smaller bodies or force other, smaller bodies into a resonance. For both, the relative size of the bodies is quite important. A value of over 900 for Mars is more than enough to clear out other bodies, or force them into a resonance, as simulations suggest a cutoff of around 1-ish is the threshold. Pluto at 0.003 would fail to do this even if the gas giants weren't there.

    12. Re: It's so ridiculously easy by dave420 · · Score: 1

      Forget it, he's rolling.

    13. Re:It's so ridiculously easy by khallow · · Score: 1

      they said lets make something useful to planetary scientists working in the solar system, and come back again when we need to do something applicable to exoplanets.

      So no, they didn't.

      No, the vast majority of the butthurt was because Pluto was no longer a planet, and had nothing to do whether it was scientific or not to call Pluto a planet. You could have had the most elegant, scientific definition ever, but if it changed the status of Pluto, the vast majority of the people would be bitching the same, because they didn't even care about the details of the actual definition.

      But we didn't have the most elegant, scientific definition ever. We had a kluge passed at the eleventh hour.

      Also, it is really annoying to present an irrational argument or decision and then claim, completely without justification, that disagreement would be unabated by actual reason or logic. Why don't you try it first?

    14. Re: It's so ridiculously easy by Rei · · Score: 3, Informative

      Mars does not gravitationally dominate its neighborhood and force things into resonance with it. The vast majority of asteroids are locked into resonances with Jupiter, not Mars. There's only about 1500 known asteroids, the Polana group, which are locked into a 2:1 resonance with Mars (Mars also has 4 trojans which do not appear related to each other).

      The Stern-Levison parameter is based around the principle of scattering small bodies, bodies far smaller than the parent, which can be scattered on a single pass at distance b to an angle greater than or equal to a given value. Pluto is a "small body" compared to Neptune, but not so compared to Mars. And Mars's Stern-Levison parameter is, again, far less than Neptune's.

      The claim that "a value of over 900 for Mars is more than enough to clear out other bodies" is false even if we ignore this troublesome "small body" aspect. Again, read the Stern-Levison paper. The value of 900 for Mars comes from assuming a scattering angle of one radian from its approach angle, which hardly means ejection or single-pass domination. It assumes 12 billion years for the age, several times older than the solar system. It relies on the "small bodies" having high eccentricities, which would probably not be the case in a gas-giant-less solar system - the lower the eccentricity, the far weaker the scattering potential. And of course, they assume actual small bodies - typical asteroid sizes.

      Interestingly enough, I would have been happy with the classification actually laid forth in Stern-Levison (2002). They proposed a size/composition matrix similar to that of stars, with all objects large enough to be in hydrostatic equilibrium included. The mass would be grouped into "subdwarf" (Ceres, Pluto, Charon, etc), "dwarf" (Mercury, Venus, Earth, Mars), "subgiant" (Uranus, Neptune, Saturn), "giant" (Jupiter), and "supergiant" categories, while the composition grouped into "rock" (terrestrial planets, asteroids), "ice" (KBOs, uranus, neptune), and "hydrogen" (saturn, jupiter). So for example Jupiter would be a "hydrogen giant planet". Pluto would be a "rocky subdwarf planet". Titan would be a "icy subdwarf satellite". Etc.

      --
      The yellowcake is a lie.
    15. Re: It's so ridiculously easy by Rei · · Score: 2

      Oh, and while we're at it, according to the IAU's definition, Jupiter shouldn't be a planet. They define planets as bodies that orbit the sun that have cleared their neighborhoods. Jupiter does not orbit the sun. It orbits the Sol-Jupiter barycentre, which is outside of the sun - the sun and Jupiter roughly co-orbit this point.

      --
      The yellowcake is a lie.
    16. Re: It's so ridiculously easy by Anonymous Coward · · Score: 0

      Ok, that is just a stupid objection... every planet orbits a barycenter. There is nothing special about the dynamics of the Jupiter-Sun pair because the barycenter is outside the Sun, as the it is the exact same dynamics as any other system. You're really reaching if you have to resort to BS like this. And why, when there are plenty of good arguments against the definition of a planet, why resort to stuff that will get you called out as stupid or wrong?

    17. Re: It's so ridiculously easy by Anonymous Coward · · Score: 0

      There's only about 1500 known asteroids, the Polana group, which are locked into a 2:1 resonance with Mars (Mars also has 4 trojans which do not appear related to each other).

      So in other words, Mars is quite capable of forcing other bodies into resonance, even when there is a more dominant influence from another planet...

      The Stern-Levison parameter is based around the principle of scattering small bodies, bodies far smaller than the parent, which can be scattered on a single pass at distance b to an angle greater than or equal to a given value.

      It is a scaling parameter that has expanded beyond the original proposal as further simulation work show it to be a pretty good threshold between bodies that can dominate influence on other bodies versus just being another member of a herd. But yes, the significance now is what it signifies over a large time scale of billions of years (not necessarily 12 billion or any other specific number now), which is more important than the single encounter deflection even if that is what helped develop it originally.

    18. Re: It's so ridiculously easy by Anonymous Coward · · Score: 0

      Aspie much? Anyone with any common sense understands that "orbits the sun" is another way of saying "is not a moon (or a sub-{1,}moon)".

    19. Re: It's so ridiculously easy by Rei · · Score: 1

      every planet orbits a barycenter.

      But few orbit a barycentre *outside either body*. When they're the same type of object we usually call these binaries or doubles.

      The place Jupiter orbits is not the sun. It's quite near the sun, but it's not the sun.

      --
      The yellowcake is a lie.
    20. Re: It's so ridiculously easy by hackertourist · · Score: 1

      The solar system barycenter wanders around, and is outside of the sun only part of the time. IIRC only the combined influence of several planets in alignment gets the barycenter to be outside the sun.

    21. Re: It's so ridiculously easy by Anonymous Coward · · Score: 0

      When they're the same type of object we usually call these binaries or doubles.

      Binary and double stars include asymmetric pairs where the barycenter is within the larger star.

      The whole concept of whether the barycenter is inside outside is not even considered that significant by many astronomers, and plenty argue against the idea of using that for the definition of a double planet, because it depends on the separation as much as the relative size.

    22. Re: It's so ridiculously easy by david_thornley · · Score: 1

      One problem with calling anything that has reached hydrostatic equilibrium (which really sounds funny, since very few bodies in the Solar System have liquid water) a planet is that there suddenly are hundreds or thousands of them. People want to be able to list the planets easily. Calling Ceres and Ganymede planets goes against traditional usage.

      I think a distinction between bodies that have reached equilibrium and bodies that have not would be an excellent one, but I don't think it should be "planet" vs. something else.

      --
      "When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
    23. Re: It's so ridiculously easy by Anonymous Coward · · Score: 0

      *** SMACK*** is the sound of dave420 going down eating his words getting bitchslapped by apk http://slashdot.org/comments.p...

    24. Re: It's so ridiculously easy by Rei · · Score: 1

      Mars is quite capable of forcing a tiny fraction of tiny bodies into resonance. That's a far cry from saying "Mars would have cleared its celestial neighborhood of the planetissimals left over after it accreted, in the absence of aid from Jupiter". People have long been abusing the Stern-Levison parameter to say things that it doesn't.

      --
      The yellowcake is a lie.
  4. Solar System by rossdee · · Score: 1

    We should send the IAU out there with some paint to draw a line (circle or ellipse) as to where the edge of the solar system is.

    1. Re:Solar System by Anonymous Coward · · Score: 0

      The boundary must be weird because it has to be far enough to include the entire orbit of Sedna, yet wiggly enough to have crossed the path of Voyager 1 five times.

    2. Re:Solar System by Anonymous Coward · · Score: 0

      It doesn't help that pop-sci can't understand that there is more than one kind of boundary, and none of them are the definitive end of the solar system. They would probably also say a ship heading out to sea has entered international waters multiple times, because the difference between EEZ and territorial waters would be to difficult to write about.

    3. Re:Solar System by Anonymous Coward · · Score: 0

      Where is the edge of the ocean? It is probably different at 9 in the morning, than 9 at night. it is probably different at 9:00:00 in the morning and 9:00:01 in the morning as well.

    4. Re:Solar System by Anonymous Coward · · Score: 0

      What's the size of those variations as a percentage of the size of the ocean, 0.01%? Depending on who you ask, the size of the solar system vary by a factor of 500, not 0.0001.

    5. Re:Solar System by Anonymous Coward · · Score: 0

      What was the variation in the "edge of the solar system" compared to the size, hmm?

      DOUBLY so when one was actually ENTERING the edge of the solar system and the other is passing out half way-ish through the helopause.

  5. And it's... by Chris+Mattern · · Score: 1

    ...Donald Trump's humility!

    1. Re:And it's... by Anonymous Coward · · Score: 0

      ...or Dick Cheney's soul!

  6. Nearby Stars??? by Anonymous Coward · · Score: 0

    The article summary says "nearby stars". If there were nearby stars, wouldn't we already know?

    1. Re:Nearby Stars??? by Anonymous Coward · · Score: 0

      The article summary says "nearby stars". If there were nearby stars, wouldn't we already know?

      We do know about a few stars that passed very close to our solar system in the (astronomically) recent past.

  7. Damn that's way out there! by Impy+the+Impiuos+Imp · · Score: 1

    Wow, 3x as far out as Pluto, which is so way way out there it was itself named for the god of the underworld, of death.

    And this is 3x further than that! In fact, it is so far out there, I officially name it (pick one):

    Trump

    Bernie

    --
    (-1: Post disagrees with my already-settled worldview) is not a valid mod option.
  8. I'm guessing his parents are ST:TNG fans... by erikscott · · Score: 1

    ...or maybe it's just required that people named Jean-Luc go into astro/planetary/aerospace lines of work. :-)

  9. Re:Most distant object in the solar system... by Anonymous Coward · · Score: 0

    No because C/1577 V1 is even farther, currently at 320 AU. In any case, this new discovery at 103 AU is definitely not the most distant known object in the solar system.

  10. What are you? I am a meat Popsicle! by TiggertheMad · · Score: 1

    Calling a celestial body a 'planet' or 'not a planet' is a Boolean classification that puts the continuous range of objects that populate the universe into two buckets, and a pack of supposedly smart scientists have to get into a slap fight over the tipping point of the definitions.

    If they had any sense, they might agree that there are probably hundreds of billions of objects out in space, some of which have the properties of the traditional view of a planet, and also the properties of of what is wasn't considered a planet. There, that wasn't hard now was it?

    --

    HA! I just wasted some of your bandwidth with a frivolous sig!
  11. IT was the least kludgy by far. by Anonymous Coward · · Score: 0

    However, it changed what a US astronomer discovered from a planet to a dwarf star.

    That this had happened to two asteroids (and actually caused the creation of the classification "asteroid" to put the damn thing in, just like "dwarf planet" did) is irrelevant because

    a) that was before you learned the planet pluto,and you damn well aren't going to change!
    b) It was some poofy European, so who cares. they're not AMERICAN!

  12. You can just spot it in the centre of this image. by dsmatthews9379 · · Score: 1

    http://i.imgur.com/yn0w8RZ.png