Slashdot Mirror

← Back to Stories (view on slashdot.org)

More Than Half of Kepler's Giant Exoplanets Were False Positives

Posted by timothy on from the let-the-universe-sort-'em-out dept.

StartsWithABang writes: By surveying an area of the sky containing over 150,000 stars visible to it, the Kepler satellite monitored each one over a multi-year period looking for periodic changes in brightness. Thousands of planetary candidates emerged via the transit method, where periodic dips of 3% or less were noted with regularity. However, a follow-up study has come out on the giant exoplanets, finding that over 50% of them aren't giant planets after all, but wound up being eclipsing binary stars. Perhaps our lone star Solar System is the oddity, after all.

5 of 88 comments (clear)

  1. Re:Confirmation bias by Anonymous Coward · · Score: 0, Informative

    Done. Under the IAU definition of a planet, that's all of them except the Solar system.

  2. Re:Confirmation bias by gstoddart · · Score: 5, Informative

    They can search for things because the candidates show a difference which suggests you should look closer.

    How the hell can you search for nothing to then use that to help you find something?

    The false positives can be pared down with closer looks. There is no way in hell you can look at all of the stars, determine they don't have planets, and then use that to find the stars which might have planets.

    The ONLY way forward on that is by finding anything which might be a positive, false or otherwise, and then exclude things which were false.

    But you sure as hell can't look at every star, rule them out as having planets, and then use that list to find the ones which do have planets -- that's completely backwards.

    I'm pretty sure if there was a better way to be looking, they'd be doing it.

    --
    Lost at C:>. Found at C.
  3. That's why they are "candidates" by mbone · · Score: 4, Informative

    Kepler has always required an independent check before moving a candidate exoplanet (with only Kepler data) to a confirmed exoplanet. That's why there are always a lot more Kepler candidates than confirmed exoplanets. From Wikipedia:

    As of January 2015, Kepler and its follow-up observations had found 1,013 confirmed exoplanets in about 440 stellar systems, along with a further 3,199 unconfirmed planet candidates

  4. so 50% is correct! by Ubi_NL · · Score: 3, Informative

    In my field of science, having a lead-finding system that returns a 50% hit-rate after confirmation is better then I've ever encountered. I'd say that this is an extremely impressive result.

    --

    If an experiment works, something has gone wrong.
    1. Re:so 50% is correct! by gstoddart · · Score: 4, Informative

      And, really think about it ... it's actually got a 100% detection rate of finding something, some fraction of which seems to be stars instead of planets.

      If I understand this correctly, none of these are "nope, there was nothing to see here", more that we're realizing that some of the candidates are stars instead of planets.

      That's not a miss in my books.

      --
      Lost at C:>. Found at C.