Stories
Slash Boxes
Comments

SoylentNews is people

posted by cmn32480 on Tuesday June 27 2017, @07:12AM   Printer-friendly
from the searching-for-keys-near-the-streetlight dept.

Ethan Siegel at Starts With A Bang brings to attention the results of the Outer Solar System Origins Survey (OSSOS). The OSSOS project, which started in 2013 (before the Planet Nine hypothesis was proposed) to survey the minor planets of the outer Solar System, has discovered and determined the orbits of well over eight hundred trans-Neptunian objects (TNOs) in its operation. They have recently published a paper that basically puts the kibosh on the Planet Nine hypothesis. Planet Nine was initially proposed to explain an apparent anomalous clustering of orbits of TNOs consistent with them being perturbed by a large planet, but the OSSOS results have found no such anomalous clustering, and are rather seeing a distribution consistent with uniform randomness.

From Forbes' Javascript-required article:

It was perhaps the most exciting idea to come out of science last year: that an undiscovered, giant world exists in our Solar System, far beyond the orbit of Neptune. This wouldn't be some tiny, frozen world like Pluto or Eris, smaller even than Earth's Moon, but a monstrous super-Earth, perhaps ten times as massive as our own world and almost as large as Uranus or Neptune in radius. As the months passed since it was first proposed by Konstantin Batygin and Mike Brown, they compiled additional evidence for it, and things were looking rosy. But a new study by Shankman et al. has turned the evidence on its head, disfavoring the planet's existence and uncovering a bias in the data itself.

[...] what they found was entirely consistent with no Planet Nine, and that the overall case for Planet Nine's existence was substantially weakened by their study. In particular, the clustering in the orientation of each orbit in space (defined by multiple variables, ω and Ω) that earlier studies, like Batygin & Brown and Trujillo & Sheppard, previously noticed simply doesn't exist in this new, unbiased study.

We find no evidence in the OSSOS sample for the ω clustering that was the impetus for the current additional planet hypothesis.

The data from this new study is quite clear that the previously observed correlation, which was the impetus for hypothesizing Planet Nine, doesn't persist into the new sample.

OSSOS also has a Frequently Asked Questions page about these findings. They don't entirely rule out the existence of a substantial (perhaps Mars-sized) planet in the outer reaches of the Solar System, but their data makes it highly improbable that a super-Earth on the scale of Uranus or Neptune might be out there.

Additional reading:
https://www.sciencemag.org/news/2017/06/new-haul-distant-worlds-casts-doubt-planet-nine


Original Submission

 
This discussion has been archived. No new comments can be posted.
Display Options Threshold/Breakthrough Mark All as Read Mark All as Unread
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
  • (Score: 0) by Anonymous Coward on Tuesday June 27 2017, @12:10PM (6 children)

    by Anonymous Coward on Tuesday June 27 2017, @12:10PM (#531873)

    I'm reminded of the apparent paradox that the average person lives in a larger-than-average town, and also that the average town is smaller than average in population.

    Ain't that just a problem with semantics, not a paradox? The meanings of the two "average"s is different.

    Average Randomly-selected person lives in a larger-than-average town.

    Average Randomly-selected town is smaller than average in population.

    Of course, your point about the observational bias still stands :)

  • (Score: 2) by FatPhil on Tuesday June 27 2017, @02:30PM (4 children)

    by FatPhil (863) <pc-soylentNO@SPAMasdf.fi> on Tuesday June 27 2017, @02:30PM (#531915) Homepage
    I believe whether it's a paradox or not is the matter of semantics.

    I view a paradox as a situation where from the same starting point (an assumption about the distribution) and two or more superficially justifiable methods of proceeding (what one selects and how) you can end up with apparently contradictory conclusions (about how typical the thing selected is).

    Equivocation, being two superficially justifiable interpretations of a word, fits into that schema quite easily.

    When I was just a kid I had a big book of mathematically-oriented paradoxes. Of course, there were the well-known stories based on propositional and predicate logic - to wit barbers, cretans, and the heterological - where all paths lead to an impossibility, which is what many view as the only true "paradoxes", but they were in the minority. Many more were set-theoretic, geometric or probabilistic, and a lot of the weirder ones pertained to the infinite. Of course, to the mathematically astute, for this majority of the examples, there was only one way to approach the problem, and only one correct answer, and therefore they were not paradoxes. However, the *superficially justifiable* approach a layman might be persuaded to use in his state of ignorance did lead to a contradictory conclusion, and so they were acceptable paradoxes by that author's definition. And I always thought that the author was justified in that definition, so I adopted it.

    I would be willing to bet that the majority of the authors represented in this list here: https://www.amazon.com/mathematical-paradoxes-Books/s?ie=UTF8&page=1&rh=n%3A283155%2Ck%3Amathematical%20paradoxes also share that definition. Given a publication date of 1972, I presume the Northrop one was the one I had.
    --
    Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
    • (Score: 2) by Immerman on Tuesday June 27 2017, @03:50PM (3 children)

      by Immerman (3985) on Tuesday June 27 2017, @03:50PM (#531967)

      Paradox itself has several disparate definitions - as relevant to statements according to Merriam Webster:
      a : a statement that is seemingly contradictory or opposed to common sense and yet is perhaps true
      b : a self-contradictory statement that at first seems true
      c : an argument that apparently derives self-contradictory conclusions by valid deduction from acceptable premises

      Mathematicians of course have their own far more rigorous definition - but if we let mathematicians define the language it would mean an end to all conversation for lack of sufficiently ambiguous terminology.

      • (Score: 2) by KGIII on Tuesday June 27 2017, @06:59PM (1 child)

        by KGIII (5261) on Tuesday June 27 2017, @06:59PM (#532070) Journal

        I'd just point out that 'average' means multiple things.

        Then again, I am a mathematician. There is no paradox, just poor understanding.

        --
        "So long and thanks for all the fish."
        • (Score: 2) by FatPhil on Wednesday June 28 2017, @12:17AM

          by FatPhil (863) <pc-soylentNO@SPAMasdf.fi> on Wednesday June 28 2017, @12:17AM (#532209) Homepage
          I too am a mathematician, and, *as I stated quite clearly above*, poor understanding can quite naturally lead to paradoxes.
          --
          Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
      • (Score: 2) by FatPhil on Wednesday June 28 2017, @12:14AM

        by FatPhil (863) <pc-soylentNO@SPAMasdf.fi> on Wednesday June 28 2017, @12:14AM (#532208) Homepage
        My usage satisfies (a) and (c) but, non-paradoxically, not (b).
        --
        Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
  • (Score: 2) by Immerman on Tuesday June 27 2017, @03:44PM

    by Immerman (3985) on Tuesday June 27 2017, @03:44PM (#531960)

    You don't have to go with randomly selected - one of the broadly accepted meanings of average in everyday usage is median - so, you line up everybody according to the size of the city/town they live in and take the median - they'll live in a larger-than-median town because cities skew the sample in their direction. For the same reason, the median-sized town will fall far below the arithmetic average size.

    Paradox, noun: a statement that is seemingly contradictory or opposed to common sense and yet is perhaps true

    I'd say that qualifies. Moreover, I'd say it also satisfies one of the classic uses of paradox as a means to illustrate profound lessons. The lesson being that 1) "average" is an extremely ambiguous term and 2) that humans are generally *very* bad at properly interpreting statistical information.

    Both of which deserve to be driven home regularly, because the sad fact is that statistics competency is appallingly low even among professional researchers - one of the groups who should be the most well versed as literally their entire career is based on using statistics to tease out details of the subject they're investigating, and a misunderstanding of what their statistical tools are telling them (p-values anyone?) can lead to years, even decades of wasted effort and false conclusions, even before you consider the wasted effort of all those others who used their conclusions as a starting point for their own research.