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Space NASA

NASA Concludes That Comets, Not Alien Megastructures Orbit KIC 8462852 (examiner.com) 105

MarkWhittington writes: Back in October, findings from the Kepler Space Telescope suggested that something strange was going on around a star called KIC 8462852. Kepler was built to detect exoplanets by measuring the cycles of dimming light from other stars, indicating that a large object was passing between them and Earth. But the dimming light cycle from KIC 8462852 seemed to suggest a lot of smaller objects swarming around it. Scientists narrowed down the explanations to either a swarm of comets or alien megastructures. NASA announced evidence garnered by two other telescopes that pointed to the comet explanation.
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NASA Concludes That Comets, Not Alien Megastructures Orbit KIC 8462852

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  • Bet you didn't consider that NASA

  • ... two Men In Black were seen leaving the Oval Office! https://www.youtube.com/watch?... [youtube.com] https://www.youtube.com/watch?... [youtube.com] PS ;-)
  • by Anonymous Coward

    It's been confirmed to be alien megastructures. NASA is trying to bury the evidence again.

  • by Anonymous Coward

    I've been saying for years that we'd probably discover alien life by watching dimming light surrounding a star that dims irregularly. Here I was hoping I'd be vindicated.

    • I've been saying for years that we'd probably discover alien life by watching dimming light surrounding a star that dims irregularly. Here I was hoping I'd be vindicated.

      Indeed, there is plenty of alien life existing in the universe. It's just unfortunate that 99.99999999 percent of it is no more than Pond Scum. Nor ever will be.

  • They LIE! They probably work for the government! It's Kolob people, KOLOB!
  • And Lister keeps insisting they are garbage pods.

  • by Anonymous Coward

    22%. Something obscures 22% of the whole side of a star larger than the sun just in our specific direction. Given that obscuration of the star in ALL directions, at 22%, is likely for long periods of time (unless some divine hand is just trying to wink this star just for us).

    Anything that is in the same system of that star (and effectively angularly the same distance to us) would have to be 22% of the size of the star in almost all directions from any point of view. So unless the "cloud" or object is right

    • by wonkey_monkey ( 2592601 ) on Friday November 27, 2015 @07:15AM (#51012539) Homepage

      Huh. Posted my reply as AC for some reason.

      To reiterate:

      22%. Something obscures 22% of the whole side of a star larger than the sun just in our specific direction.

      No. Something blocks 22% of the light emitted in our direction for some amount of time in a regular cycle.

      how could a few comets create this sort of thing unless the "clouds" they create are sucked into the star almost immediately?

      Why would you expect the clouds to be "sucked in" at all?

      • The thing I don't get is how comets could possibly block 20% of the star's output. From what I remember, some astronomer said that if there were a Jupiter-sized planet orbiting the star, that would only block 1% of the star's output. If a Jupiter-sized planet would only block 1%, how the heck would some comets block 20 times more?

        • how the heck would some comets block 20 times more?

          How many is "some comets"? Why couldn't "some comets" block 20% of the light from a star? For that matter, why couldn't one comet do it? Remember a comet isn't just the nucleus. There's also a tail, which can be thousands of times longer than a mere planet.

          Just have a look at the illustration that leads the article (probably not entirely to scale, but still).

          • Well again, given that a gas giant can only block 1-2%, this would have to be a really friggin' huge comet, right? A comet bigger than Jupiter? That doesn't sound likely. Sure, the tail might help, but still comet tails don't block light the way a planet does, they're just a collection of dust.

            • Well again, given that a gas giant can only block 1-2%, this would have to be a really friggin' huge comet, right? A comet bigger than Jupiter?

              A comet tail bigger than Jupiter. Such a thing has been observed in our own solar system.

              Sure, the tail might help, but still comet tails don't block light the way a planet does, they're just a collection of dust.

              They block light in exactly the same way a planet does, since they are also just a collection of atoms, just more diffuse.

              A few dozen metres of water vapour in the form of clouds can block plenty of the light from our star.

              Even if a comet tail only blocks, say, 0.1% of the light per million kilometres, it would still block a total of 40% of the light if you were looking straight down it at a star (assuming a length of 5

              • Yeah, but isn't the length of the tail irrelevant, because the tail would be pointed directly towards Earth (since it's blown by the stellar wind from the star, and the presumed comet is directly between that star and Earth)? I thought comet tails always pointed directly away from their star.

                • The length is relevant because all of that dust, seen straight on, blocks a lot of light. Stack enough window panes (less than you'd think, probably) on top of each other and eventually you won't be able to see anything through them at all.

                  Then it's just a question of how wide a comet's tail can get, in order to get sufficient coverage of the star's shape as seen from Earth. And since the tail can be 720x longer than the star's diameter, I don't think it's much of a leap to think that it could spread out en

                  • The length is relevant because all of that dust, seen straight on, blocks a lot of light

                    Right, I see. I was thinking you meant that the huge length, seen lengthwise, would block a lot of light just because of the sheer length, but this makes more sense since lengthwise it wouldn't be that dense.

                    How about the other poster's brown dwarf idea? Could this be caused by a brown dwarf in orbit around the star? Those things can get really big. Effectively, it'd be a multi-star system. Or do brown dwarves emit

            • Am I the only one thinking a couple of brown dwarfs?
              • That's not a bad idea actually. I think I read that Jupiter is just a bit too small to be a brown dwarf, but there's probably a good size range there, so maybe there's a large brown dwarf there.

            • A comet the size of Jupiter would be a Jupiter.

              To get this amount of dimming, you'd need an awful lot of comets (possible - let's say a Jupiter-mass worth of them), and for them to be in a relatively compact group. That would be (as I mentally draw models of the system) concentrated around something like 1/10th of the circumference of the orbit. And you'd need something to hold them in that position.

              My mental imaging is suggesting that this could be a dense "Trojan" swarm held in place by a "Super-Jupiter

        • The thing I don't get is that the GP actually wrote "reiterate" with a straight face.
  • You mean the Kician Prince doesn't really exist? Shit!

  • The title is missing a comma. It should be:
    NASA Concludes That Comets, Not Alien Megastructures, Orbit KIC 8462852

    Not:
    NASA Concludes That Comets, Not Alien Megastructures Orbit KIC 8462852
    • Would it kill the editors to use proper grammar?

      Yes. Yes it would. Or at least, if it would, they would be safe.

  • guess we are safe then...... for a while

  • Am I wrong about this? Forget the alien whatever, the idea of thousands of large comets orbiting a planet sounds neat to me.

  • by Anonymous Coward on Friday November 27, 2015 @12:44AM (#51011477)

    I am a registered Planethunter - have been for three years. You just skimmed a recycled story from a couple days ago with the only "new" information is that no infrared increase had been detected - which is no news - zero. We have known this since Tabitha Boyjian's paper which suggested the comet swarm theory to begin with and predicted that IF it was cometary debris from a (unprecedented and never before observed or proven phenomenon) then it would show an increase in IR - it does not - so far. We will not know that until most likely February of 2017 which is the most likely estimated recurrence of the next transition.
    If there are no further transitions then that in itself would be bizarre since the likelihood of catching such a brief phenomenon at exactly the right moment at that exact point in the sky would be literally astronomically small.
    Which, by the way, Boyjian's paper points to as one of the weakest arguments for the comet swarm hypothesis.
    So - once again - there is nothing we know now that we did not know two months ago other than a *second* confirmation that there has been no increase in the infrared. All we have is a tweak to the cometary swarm theory that could, possibly explain (by adding an even less likely scenario) how there could be no IR increase now but "may" show an increase during the next transition. Which will most likely be 2017, at which point if there's still no IR increase we'll be exactly where we we're two months ago and likely still are.
    Next time take some time to check the story instead of just regurgitating 2-day old feeds.

    • I am a registered Planethunter How does one register as a planethunter?

    • I wonder if we are witnessing what a system would look like during a cometary disruption event like our Late Heavy Bombardment period with a lot of close-in comets with planets' names on them.

  • It's both a comet & a megastructure. Just hope it doesn't head our way...

    http://ourstarblazers.com/vaul... [ourstarblazers.com]

  • How did the aliens get the comets to do that and why?
  • IT'S AN ALIEN CONSPIRACY!
    Don't believe this "bunch of comets" theory for a second.
  • I'm pretty sure the Necromongers are always mistaken as comets too. So everyone needs to prepare to go visit the Underverse. And remember you keep what you kill.
  • That's just what they want us to believe so we don't panic. Duh.

  • by Dr. Spork ( 142693 ) on Friday November 27, 2015 @12:35PM (#51013969)

    I think it's amazing that there could be a system with enough comets to block out such a big portion of starlight. It gets my imagination going because when I picture the future of human expansion, I don't see us living on the natural surfaces of planets, putting up with all the ways in which they are ill-suited to our comfort (wrong gravity, wrong color starlight, wrong day/night cycle for our circadian rhythm, wrong atmosphere, wrong temperature range, too much radiation, etc.). I know that people want to address some of these problems with some sort of transforming, and that will make sense on some planets, but most stars will not have eligible ones.

    However, most stars will have enough ordinary junk in their orbit that we will be able to manufacture (with self-replicating AI machines) a perfectly awesome and huge spinning habitat that could have a habitable surface area comparable to that of the Earth. The easiest source for the materials for such a habitat are smallish rocks, because it takes so little energy to eject habitat material from a quarry on a rock with such a small gravity well. A colony would simply dispatch an AI-controlled factory that would convert asteroid material into duplicate AI factories, plus fuel and thrusters that get these to other asteroids. Then the factories retool to convert the asteroids into parts for a giant spinning space station, in which the interior light, atmosphere, gravity and temperature are optimized for terrestrial life, while the star-facing exterior is covered with solar panels, and the shady side is a spiky forest of heatsinks. If the orbit is close enough to the star, the panels alone should generate enough energy to power all the systems and more.

    It's very 1960's thinking to picture ourselves living on the surfaces of other planets, and yet, even many scientists have not gotten past that obsolete picture. AI technology plus robotics will allow us to thrive even in extrasolar systems that have nothing but perfectly ordinary crap floating in orbit, because perfectly ordinary crap is exactly what we and every important feature of our biosphere are made of.

    What's exciting about a system like this is that if there are lots of comets, it means that there's a lot of great crap within arm's reach from which to build a gigantic new home.

    • I think it's amazing that there could be a system with enough comets to block out such a big portion of starlight.

      They think the first dimming event was caused by one comet.

      I think the thing to grasp might be that - as the illustration on the article shows, albeit with some artistic licence - you need to imagine looking at the star through the entire millions-of-kilometres length of a dusty comet tail (which streams directly away from the star, so directly towards us). That'll block a lot of light, I'm guessing.

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