Recent Kuiper Belt discoveries cast doubt a big planet exists there

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The uncertainty of science: Despite predictions by some scientists that a big planet exists in the Kuiper Belt beyond Neptune, recent new discoveries of new objects there cast doubt on its existence.

If the additional big planet existed, the newly discovered objects would have shown some clustering, shepherded by its gravity.

“We find no evidence of the orbit clustering needed for the Planet Nine hypothesis in our fully independent survey,” says Cory Shankman, an astronomer at the University of Victoria in Canada and a member of the Outer Solar System Origins Survey (OSSOS), which since 2013 has found more than 800 objects out near Neptune using the Canada-France-Hawaii Telescope in Hawaii. In a paper posted to arXiv on 16 June and soon to be published in The Astronomical Journal, the OSSOS team describes eight of its most distant discoveries, including four of the type used to make the initial case for Planet Nine.

“I think it’s great work, and it’s exciting to keep finding these,” says Scott Sheppard, an astronomer at the Carnegie Institution for Science in Washington, D.C., who was among the first to suspect a large planet in the distant solar system. But he says three of the four new objects do have clustered orbits consistent with a Planet Nine. The fourth, an object called 2015 GT50, seems to skew the entire set of OSSOS worlds toward a random distribution. But that is not necessarily a knockout blow, he says. “We always expected that there would be some that don’t fit in.”

Note that I do not consider “Planet Nine” to be an accurate name for this theorized planet. Either it is #10, after Pluto, or one of a large number far more than nine, based on a new proposed and more logical planetary definition. The present definition however does not work.



  • Diane Wilson

    The current definition was voted in by the Plutocracy of Giant Planets; they have a Vesta’d interest in preventing a whole Ceres of new planets trying to Charon the wealth. They will Makemake any changes difficult.

    I am so very sorry. Shoot me now.

  • geoffc

    Diane, imagine the next door kid from Incredibles “THAT WAS AWESOME!”

  • Joe

    Diane, enjoyed that!

  • Edward

    We send them to school and buy them their books, and what do we get? Punsters like Diane.

    For a long time, “Planet Ten” has been written with Roman numerals as Planet X: (1-minute of “Duck Dodgers in the 24th and a Half Century”)

    And besides, who made the IAU the arbiter of planets? Next thing you know, someone will say that Star Registry’s names for stars is not official — yet that company sends copies of its books of star names to the Library of Congress, so those MUST be official names. Right?

  • Diane Wilson

    Speaking of the IAU, the version of the current rules that was actually voted on required that a planet must have “cleared its neighborhood” of other objects, or words to that effect. Even at the time, based on the number of known Near Earth Objects, Earth should have been classified as a dwarf planet.

  • wayne

    Great stuff!

    I have an old Scholastic Book from the mid 60’s, “The Search for Planet X.”

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