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Tenth planet Thread (merged)

  1. Jul 29, 2005 #1


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    A new solar system object past Pluto and Neptune's object with a moon, which is smaller than Pluto has been discovered. (This is also very delicate wording. The sensational way to word it would be: "New Planet Discovered Past Pluto!", but given that Pluto just barely qualifies to be a planet, this would clearly not).

    The best quote from the story (in the duh! category):

    Details here: http://www.space.com/scienceastronomy/050729_large_object.html
  2. jcsd
  3. Jul 29, 2005 #2


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    BREAKING NEWS: trans-Neptunian object discovered

    "Astronomers have found a large object in the Solar System's outer reaches. It is being hailed as "a great discovery".

    Details of the object are still sketchy. It never comes closer to the Sun than Neptune and spends most of its time much further out than Pluto.

    It is one of the largest objects ever found in the outer Solar System and is almost certainly made of ice and rock.

    It is at least 1,500km (930 miles) across and may be larger than Pluto, which is 2,274km (1,400 miles) across."

    Distant object found orbiting Sun
  4. Jul 29, 2005 #3
    Hmmm... a possible new planet member of our solar system(albeit small)? Nice.
  5. Jul 29, 2005 #4
    Not so easy, guys... Check these links:


    This is ANOTHER object! We have THREE new big objects:

    2003 EL61
    2003 UB313
    2005 FY9

    Links for more info about each object:


    And 2003 UB313 is at least the size of Pluto - it could be significantly larger. Would be interesting to know, will these discoveries change the mission to Pluto?
  6. Jul 29, 2005 #5
    You can see their orbits here:

    http://neo.jpl.nasa.gov/orbits/2003el61.html [Broken]
    http://neo.jpl.nasa.gov/orbits/2003ub313.html [Broken]
    http://neo.jpl.nasa.gov/orbits/2005fy9.html [Broken]

    2003EL61 is 51 AU from Sun, brightness: 17.7 mag
    2003 UB313 is 97 AU from Sun, brightness: 18.9 mag
    2005 FY9 is 51 AU from Sun, brightness: 17.4 mag
    Last edited by a moderator: May 2, 2017
  7. Jul 30, 2005 #6
  8. Jul 30, 2005 #7


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  9. Jul 30, 2005 #8
    Very nice job Tony!
  10. Jul 30, 2005 #9
  11. Jul 30, 2005 #10


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    Dearly Missed

    http://science.nasa.gov/headlines/y2005/29jul_planetx.htm?list45222 [Broken]

    Here is a NASA press release about the one that is bigger than pluto
    (IIRC it is 2003UB313)
    quotes Mike Brown to the effect that even if the albedo were 100 percent it would still be as big as Pluto
    that's how bright it is.
    so since not perfectly reflective, must be larger
    Last edited by a moderator: May 2, 2017
  12. Jul 30, 2005 #11

    Very incredible!, they have discovered Planet X!

    http://neo.jpl.nasa.gov/orbits/2003ub313.html [Broken]
    Last edited by a moderator: May 2, 2017
  13. Jul 30, 2005 #12
    10th Planet Discovered

    Well folks, the 10th "planet" has finally been found. See
    If you can find more online info please let me know. Thanks.

  14. Jul 30, 2005 #13
    you forgot Sedna
  15. Jul 30, 2005 #14
    I didn't forget it. This is Sedna. It has been confirmed that Sedna exists. This is the confirmation. The existance of Sedna has not been confirmed before this.
  16. Jul 30, 2005 #15
    i thought you were talking about the new one

    edit: you need an account for the link
  17. Jul 31, 2005 #16
    No, no, no... The existence of Sedna was confirmed long before... We are here talking about two newly discovered objects, 2003UB313 (nicknamed "Lila"), which should be considered as the 10th planet (because of its probable 2600 Km diameter), and 2003EL61 (nicknamed "Santa"), which is approximately the size of Sedna. But these last objects are not Sedna, which "code" is 2003VB12.

    These 2 discoveries have created a lot of confusion in the medias because they were announced almost at the same time.
  18. Jul 31, 2005 #17
    This is wonderful!

    Thank you all for the nice links. :)
  19. Jul 31, 2005 #18
    According to BBC some people want to name this new "planet" Xena (The warrior princess) :yuck: It sounds stupid for a plaanet...
  20. Jul 31, 2005 #19


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    So does 'Earth', but we're stuck with it. :rolleyes:
  21. Aug 1, 2005 #20


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    Lila I like. Santa and Xena have got to go.
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