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Pluto is no longer a planet

  1. Aug 24, 2006 #1
    http://www.cnn.com/2006/TECH/space/08/24/pluto.ap/index.html [Broken]

    "PRAGUE, Czech Republic (AP) -- Leading astronomers declared Thursday that Pluto is no longer a planet under historic new guidelines that downsize the solar system from nine planets to eight."

    .......... :rofl:
     
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Aug 24, 2006 #2
    I think I will just wait about ten years before trying to look up what the planets in our solar system are.
     
  4. Aug 24, 2006 #3

    Chi Meson

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    Dang it! I just bought stock in Charon!
     
  5. Aug 24, 2006 #4
    There going to change it...Everone likes pluto...
     
  6. Aug 24, 2006 #5
    Let's riot until they ban changing the number of planets.


    Anyone? *Grabs picket*

    ^Also: "They're". Pluto(capitalized).

    </EnglishOCD>
     
  7. Aug 24, 2006 #6
    Yeah lets ban the astromers against Pluto!!

    Who's ready for Planet Killer Champions!
     
  8. Aug 25, 2006 #7
    It always makes me laugh to see how much people actually care about some stupid sphere. They actually organised a big conference on this in Prague, i believe, just to define "what is a planet" ???

    Talkin' about your udder waiste of money.

    marlon
     
  9. Aug 25, 2006 #8

    EL

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    Won't this have some inpact on Astrology?
     
  10. Aug 25, 2006 #9
    In my opinion, this decision was unwise. Does it serve any scientific purpose?
     
  11. Aug 25, 2006 #10
    :rofl: :rofl: :rofl:

    marlon
     
  12. Aug 25, 2006 #11

    EL

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    If Pluto would have remained a planet, at least three more objects in our solar system should also qualify as planets. And in a near future we would probably find hundreds of more such "mini-planets" outside Pluto, and in that case I'd feel quite sorry for the children having to learn all the names in school...
     
  13. Aug 25, 2006 #12

    Astronuc

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    The meeting in Prague is the 26th General Assembly of the International Astronomical Union (IAU) or UAI in French.

    http://www.astronomy2006.com/

    http://www.iau.org/IAU_MEETINGS.110.0.html [Broken] - a number of meetings in Prague coincident with the GA.
     
    Last edited by a moderator: May 2, 2017
  14. Aug 25, 2006 #13

    SpaceTiger

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    Classification schemes serve as phenomenological guides that aid in the study of the formation and subsequent evolution of some set of objects. Optimally, the different categories would reflect not only differences in present appearance and behavior, but also physical history. In this case, Pluto's origins and evolution may have more in common with that of other Kuiper Belt objects than of the official eight planets.

    One might ask, does a study of Kuiper Belt objects include Pluto? Does a simulation of evolution of planetary orbits include it? Ultimately, the answers to these questions will depend on the study in question. Scientists can choose to conduct their studies in any way they see fit (perhaps ignoring the official classification scheme), but it's usually convenient to have some kind of consistency.

    Personally, I don't think it's earth-shattering and am amused that people get so worked about it, but I do think it's important to have a definition (even if somewhat vague). In this respect, any decision made by the IAU would be a step forward.
     
  15. Aug 25, 2006 #14

    Astronuc

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    Yeah, they just retroactively invalidated all previous horoscopes. :rofl:
     
  16. Aug 25, 2006 #15
    One page less in science textbooks and one more in history textbooks. :wink:
     
  17. Aug 25, 2006 #16

    EL

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    Ah, so now we know why they never worked before!
    Guess the new Astrology will be much more successful...
     
  18. Aug 25, 2006 #17
    If there is a definition for Kuiper Belt objects and Pluto meets the definition, then Yes. If it doesn't meet the definition, then No. If there is no definition, the the IAU should have made one. What has this got to do with the issue at hand?
     
  19. Aug 25, 2006 #18

    SpaceTiger

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    As I said, the origins and evolution of Kuiper Belt objects are likely different from that of planets. Putting it in both categories may not make sense, depending on what one wishes the classification to reflect.
     
  20. Aug 25, 2006 #19
    But this is not what the IAU did. They classed together Pluto and Ceres. The reason Pluto was kicked out of the limousine had to do with its orbit, not its history. If they needed a word for "Planet, but not Pluto", I think they should have made one up.

    There are attempts being made to find planets revolving about other stars. Are these attempts now to be relabeled, or are we not interested in extra-solar Kuiper Belt objects?
     
  21. Aug 25, 2006 #20

    SpaceTiger

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    Here's a quote from the article:

    In other words, Pluto is part of a "belt", so it has not cleared the region around its orbit (a facet of its history/evolution) and is not to be classified as a planet.


    Everything found (or being looked for) so far would probably fall into the definition of a planet, not a Kuiper Belt object or asteroid.
     
    Last edited: Aug 25, 2006
  22. Aug 25, 2006 #21
    Then here's to finding things that are not being looked for. Anyway, I'm off the case. It turns out that Pluto's fate is similar to that of Ceres.

    http://en.wikipedia.org/wiki/1_Ceres

    By the way, SpaceTiger, it seems that the sturdy classification scheme you desire did not come about:


    Or Kuiper Belt object.
     
  23. Aug 25, 2006 #22

    SpaceTiger

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    They're not being looked for because we're not capable of detecting them. With the possible exception of pulsar planets (which are so strange that I'd question classifying any of them alongside our own planets), any orbiting body our instruments can see would clear its orbit on a very short timescale.


    I'm in partial agreement on this point, but I still think this is a step forward. Previously, the planets were defined based on our history rather than theirs, an unpleasant state of affairs for a scientific classification scheme.
     
  24. Aug 25, 2006 #23
    And here's to detecting things you didn't think you could.
     
  25. Aug 25, 2006 #24

    SpaceTiger

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    So you're saying we should spend money to look for things that are way below our detection threshold?
     
  26. Aug 25, 2006 #25

    Moonbear

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    :rofl:

    One of my friends has been talking on and on about this this week. I guess he's been following it in the news or something. My reaction was more, "It's still there, right? It hasn't suddenly disappeared or gone zooming out of its orbit, right? Then it's just an issue of semantics."

    I wonder if the textbook writers are backing this change? It would mean all the schools would need to update the textbooks to remain current. :rofl:

    I suspect the kids would like it if the list got too long. Once it gets to that point, it's no longer something the schools think is worth memorizing, and instead, they put a sentence in like, "There are now over # known planets." And then teachers awe the class by telling them something like, "Would you believe that back in the 20th Century, they thought there were only 9 planets?!" That's when the kids all giggle and are shocked that people used to be that ignorant. :biggrin:
     
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