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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.
"A fanatic is one who can't change his mind, and won't change the subject." -- Winston Churchill
We all live in a lone star state, even those of us who don't live in Texas.
Even if 99% of the 2000+ exo-planets are not exo-planets, that's still 20 detected. Which isn't half-bad considering how long we've been seriously (space based telescopes etc) looking for them.
The conclusions in the article are weird to me. They are saying 52% of the exoplanets may not be exoplanets for this Kepler system example. Even if that holds, given the 2000+ exoplanets, if 48% are still probably exoplanets, that's 960 of them.
I'm assuming that Wikipedia's exoplanet count is sort-of right, and that it hasn't been already halved because we think 50%ish of them are probably other things.
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.
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.
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.
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.
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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."
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.
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:
Any sufficiently advanced troll is indistinguishable from an idiot.
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.
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.