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

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.

12 of 88 comments (clear)

  1. Re:Giant science lever set to "Republican" no doub by halivar · · Score: 4, Insightful

    "A fanatic is one who can't change his mind, and won't change the subject." -- Winston Churchill

  2. People in Texas must be loving this by macraig · · Score: 4, Insightful

    We all live in a lone star state, even those of us who don't live in Texas.

  3. a bit exaggerated by NostalgiaForInfinity · · Score: 4, Insightful

    They are "false positives" in the sense that the stellar companion may be a small star or a brown dwarf instead of a "planet". But the distinction between a "big hot gas giant" and a "brown dwarf" is fairly academic, in particular if you're concerned with things like habitability.

  4. They didn't get it perfect. Must be useless by enjar · · Score: 4, Insightful

    So someone comes up with a list of things that might be planets, then someone does further analysis and finds out that some aren't. Even (gasp) 52% of them! Science must therefore be useless.

    No, that's how science works -- you do an experiment, examine the results, then refine your experiment. Or someone else does. Repeat ad nauseum.

    1. Re:They didn't get it perfect. Must be useless by gstoddart · · Score: 5, Insightful

      More importantly, they found something using the technique. The technique worked.

      That they then looked closer and said "wow, not a planet, but another star" doesn't mean anything other than we're getting remarkably good at identifying candidates and then figuring out what they actually are.

      I'd say it's a great success, because they're actually finding things to look closer at. If some of those turn out to be not planets, but still actual things, then the technique is working just fine.

      --
      Lost at C:>. Found at C.
  5. 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.
  6. Re:Giant science lever set to "Republican" no doub by tarpitcod · · Score: 5, Funny

    The "Giant science lever" settings guide.

    Republican - Cite crappy statistics.

    Democrat - Cite the fact the launch vehicle was Government funded.

    Socialist - Cite the fact that the mission is peaceful and Government funded.

    Libertarian - Cite the fact that you can choose if you want to read the article or not.

    Capitalist - Cite the fact that the planets are new markets just waiting for buy refrigerators and huge untapped market.

    Old Slashdot - Cite the fact that the featured article is kinda crappy, has crappy thinking, and that in your day you could have figured this out on an HP-35 quicker and more accurately, but you have used your HP-35 as a controller for a Beowulf cluster of MIPS processors you desoldered from old crappy routers.

    New Slashdot - Cite the fact that citing facts is a micro-aggression against everyone else who might disagree with any of the facts, and complain that MIPS is unfairly represented and RPN is an elitist system hardly better than the slide-rules which killed trees that it replaced. Start the reply with "TLDR - Micro-aggressions from old calculator RPN using nerds harmful to community cohesiveness."

  7. Re:Confirmation bias by Z00L00K · · Score: 4, Insightful

    I wouldn't really call it false positives since there's a sliding scale between giant planet and star.

    It would have been a lot worse if it was revealed that there was no object at all.

    --
    If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
  8. 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

  9. Re:Confirmation bias by GrumpySteen · · Score: 4, Funny

    Any sufficiently advanced troll is indistinguishable from an idiot.

  10. 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.
  11. 'Transit' method relies on planar alignment by BenJeremy · · Score: 4, Insightful

    It's terribly incorrect, to say, as the summary says, "Perhaps our lone star Solar System is the oddity, after all" - to the point of blunt stupidity.

    Kepler's transit method will find some exoplanets, or at least the signs that something is worth taking a closer look at, but it also relies on a system's elliptical plane being aligned just so such a large exoplanet can cross the path of the star - in other words, we have to be able to see that plan edge-on. This reduces the likelihood of practically using this method to actually find something around 100-to-1, if it even exists.