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Thread: Up to 22% Dips Detected in Starlight 1,500 LY Away

  1. #31
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    Quote Originally Posted by Fiery Phoenix View Post
    I don't think the paper has addressed that. That said, I can't think of any internal processes that would cause the star to be so unstable as to dim by 15-22%. (Also, I believe it is a main sequence star.)
    I went and looked at the paper and they did address it, suggesting three or four possibilities, but they rejected them.
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  2. #32
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    Quote Originally Posted by Jens View Post
    I went and looked at the paper and they did address it, suggesting three or four possibilities, but they rejected them.
    Makes sense. I have yet to look at the actual paper myself so I should probably do that.
    “Of all the sciences cultivated by mankind, Astronomy is acknowledged to be, and undoubtedly is, the most sublime, the most interesting, and the most useful. For, by knowledge derived from this science, not only the bulk of the Earth is discovered, but our very faculties are enlarged with the grandeur of the ideas it conveys, our minds exalted above their low contracted prejudices.” - James Ferguson

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    Quote Originally Posted by Fiery Phoenix View Post
    Makes sense. I have yet to look at the actual paper myself so I should probably do that.
    It's amazing (I found out myself as well) how much help actually reading the paper can be in deciding whether the authors actually addressed an issue or not.
    As above, so below

  4. #34
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    Quote Originally Posted by Selfsim View Post
    Yes ... and then, immediately following, they say:
    That forward tail argument seems a stretch too far. As for the slow-ingress-fast-egress problem, I still like my solution, which the paper did not consider. It's a little hard to put concisely in words. I'll try again...

    It's a very eccentric orbit. At the beginning of the transit, the object is far from the star, but slowly approaching pericenter. At the end of the transit, it's very near the pericenter, so it's moving much faster.


    But, as cjameshuff notes, if a planet like Jupiter only dims a star's light by something like 1%, why are we even considering comets? A cometary envelope with an effect an order of magnitude larger than Jupiter? Pretty doubtful. A swarm of comets? Pretty doubtful since the D800 event appears fairly dispositive of a single object.

    I guess a planet-like body much, much larger than Jupiter is ruled out, since it would then be visible as a star in its own right.

    A definite conundrum.
    Everyone is entitled to his own opinion, but not his own facts.

  5. #35
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    Quote Originally Posted by Jens View Post
    It's amazing (I found out myself as well) how much help actually reading the paper can be in deciding whether the authors actually addressed an issue or not.
    Indeed. I was going by the reports
    “Of all the sciences cultivated by mankind, Astronomy is acknowledged to be, and undoubtedly is, the most sublime, the most interesting, and the most useful. For, by knowledge derived from this science, not only the bulk of the Earth is discovered, but our very faculties are enlarged with the grandeur of the ideas it conveys, our minds exalted above their low contracted prejudices.” - James Ferguson

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    I suspect that the cometary scenario was emphasized because it was the least improbable natural explanation, even though it still doesn't seem very satisfactory. Since we know so little of life in the universe, it's not clear that this comet scenario is more likely than one involving technological megastructures.

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    So the main missing component in most of these scenarios is a system wide, dust re-emitted IR?

    Anybody mind if the crazy guy applies his imagination to this?

    A) Why not look into some sort of dust corralling phenomena? Magnetic field sweeping everything up before we had a chance to see the dust cloud?

    B) The collision had only happened a month, (or a few decades) before we first noted the dip? Stuff hasn't had time to disperse through the system? Is there even a model for a what a very recent exoplanet merger even looks like? Would the Earth/Thea merger have dusted us up like we expect for this place?

    C) Why is newness more improbable that technology?

    D) How long after T+1 on Collision Day does a system wide dust cloud form?

    Crap. This problem is going to occupy my head rent-free for a week.
    Time wasted having fun is not time wasted - Lennon
    (John, not the other one.)

  8. #38
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    Quote Originally Posted by BigDon View Post
    Why is newness more improbable that technology?
    People want to believe?

    ETA: That is to say, people would really like this to be an alien civilization. It would be much cooler than a planetary collision.
    I may have many faults, but being wrong ain't one of them. - Jimmy Hoffa

  9. #39
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    Quote Originally Posted by Extravoice View Post
    People want to believe?

    ETA: That is to say, people would really like this to be an alien civilization. It would be much cooler than a planetary collision.
    of course we do. If it were an alien civ, it would be paradigm changing on an epic level for humanity. It probably isn't it though sadly.

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    Quote Originally Posted by Ross 54 View Post
    I suspect that the cometary scenario was emphasized because it was the least improbable natural explanation, even though it still doesn't seem very satisfactory. Since we know so little of life in the universe, it's not clear that this comet scenario is more likely than one involving technological megastructures.
    This is basically the impression I am getting myself. The authors emphasize comets/comet tails but that is still not a very convincing argument.

    Is it aliens? We obviously don't know. But at least I can say a Dyson sphere-like structure would more or less give similar readings in the light curve.
    “Of all the sciences cultivated by mankind, Astronomy is acknowledged to be, and undoubtedly is, the most sublime, the most interesting, and the most useful. For, by knowledge derived from this science, not only the bulk of the Earth is discovered, but our very faculties are enlarged with the grandeur of the ideas it conveys, our minds exalted above their low contracted prejudices.” - James Ferguson

  11. #41
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    The old child's song "twinkle twinkle little star" comes to mind.

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    Two planets coming together at less than the speed of sound in silica, I've heard, won't blow the crap out of each other but settle in. Since planets nearly always orbit in the same direction, either one spirals in or the other spirals out.

    So now we have two cores that haven't quite merged, that have a slight, or not so slight, dumb-bell shaped to them. This is now constantly dinking the moment of inertia for the newly formed object so that and the skewed angular momentum are throwing it's orbit willy-nilly around the star.

    How does that one sound?

    Don't worry, I'll come up with more. I can't help it.
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    (John, not the other one.)

  13. #43
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    Quote Originally Posted by BigDon View Post
    Two planets coming together at less than the speed of sound in silica, I've heard, won't blow the crap out of each other but settle in. Since planets nearly always orbit in the same direction, either one spirals in or the other spirals out.

    So now we have two cores that haven't quite merged, that have a slight, or not so slight, dumb-bell shaped to them. This is now constantly dinking the moment of inertia for the newly formed object so that and the skewed angular momentum are throwing it's orbit willy-nilly around the star.

    How does that one sound?

    Don't worry, I'll come up with more. I can't help it.
    Two planets eclipsing 15-20% of a star's light?

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    Quote Originally Posted by BigDon View Post
    Two planets coming together at less than the speed of sound in silica, I've heard, won't blow the crap out of each other but settle in. Since planets nearly always orbit in the same direction, either one spirals in or the other spirals out.

    So now we have two cores that haven't quite merged, that have a slight, or not so slight, dumb-bell shaped to them. This is now constantly dinking the moment of inertia for the newly formed object so that and the skewed angular momentum are throwing it's orbit willy-nilly around the star.

    How does that one sound?

    Don't worry, I'll come up with more. I can't help it.
    If a single gas giant barely even eclipses 1% of its host star's light during a transit, then I doubt a second planet would make any appreciable difference.

    It's safe to say this has nothing to do with planets. We know these aren't periodic dips as well.
    “Of all the sciences cultivated by mankind, Astronomy is acknowledged to be, and undoubtedly is, the most sublime, the most interesting, and the most useful. For, by knowledge derived from this science, not only the bulk of the Earth is discovered, but our very faculties are enlarged with the grandeur of the ideas it conveys, our minds exalted above their low contracted prejudices.” - James Ferguson

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    I had the idea, years ago, about eclipsing a star, in a pattern form, in order to send a very slow message across space. Perhaps these dip patterns could be analysed to see if they contain any code information...

  16. #46
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    although if they had the ability to block 20% of the star they they might aim at a higher information rate, with a faster flicker.

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    Quote Originally Posted by Cougar View Post
    It's a very eccentric orbit. At the beginning of the transit, the object is far from the star, but slowly approaching pericenter. At the end of the transit, it's very near the pericenter, so it's moving much faster.
    I think the problem with that is, IIRC, there doesn't seem to be any periodicity. So if it were a single object, or indeed a group of manmade objects orbiting, you would expect to see periodicity. I think they invoked the possibility of comets because it would be a chaotic event with comets interacting, and so it would be hard to detect any periodicity. But I'm guessing a bit.
    As above, so below

  18. #48
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    Are the researchers confident that the blocking is taking place within that star system and not at some point closer to Earth? Or do the short durations rule that out?

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    Quote Originally Posted by Jens View Post
    I think the problem with that is, IIRC, there doesn't seem to be any periodicity. So if it were a single object, or indeed a group of manmade objects orbiting, you would expect to see periodicity. I think they invoked the possibility of comets because it would be a chaotic event with comets interacting, and so it would be hard to detect any periodicity. But I'm guessing a bit.
    Artificial objects would not necessarily give a clearly periodic signal. You could easily have multiple clumps of structures irregularly arranged along orbits with a range of periods, and the clumps themselves could vary in shape over time, making a given peak hard to recognize.

    I don't see why comets would interact to any significant degree...they're small, they don't have much mass to influence each other with. A very large quantity of debris from a planetary collision might, and would be able to cover a wide range of orbit periods with irregular clumps and produce a signal like that observed. Just...where's the dust? Blocking that much sunlight takes a lot of cross-sectional area, and to accomplish that takes either small particles (dust that should be radiating lots of infrared in all directions), thin structures (artificial objects), or a huge amount of material that is for some reason floating around in many relatively large pieces that are apparently not consolidating into a new planet or colliding to make dust...(or the dust is somehow being removed faster than we expect)

  20. #50
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    Silly question, could it be a distant foreground object causing the dip?

    I would love a Dyson Sphere, but it would also be cool to have a stream of material causing the dip. It appears that they have ruled out dust around the star itself, but does this also rule out puffs of dust passing between us and the star? It would be very interesting if the dips were related to material cast off by the formation of a different star in the foreground. Baby stars are sort of dusty until they blow material away. Perhaps we are seeing the remnants of stellar formation between us and KIC 8462852.

    It would make for interesting model data if we were seeing dust from another star's formation or dust from KIC 8462852's formation. The first would be interest as we would have more data on what happens when stars carve out their system. Dust from KIC 8462852 would be crazy, how would it change temperature so it wasn't immediately obvious? I doubt the second is possible, but it would be neat.

    Rogue planets would also be interesting, but I believe they are easily identified by IR, which has been ruled out. Besides, how many rogue planets could be transiting between us and it?
    Solfe

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    Quote Originally Posted by Solfe View Post
    Rogue planets would also be interesting, but I believe they are easily identified by IR, which has been ruled out. Besides, how many rogue planets could be transiting between us and it?
    If you're suggesting that a number of rogue planets are perfectly aligned with us and the star such that they dim its light output by 20%+, then that strikes me as an impossibly low probability. It's an interesting thought nonetheless.
    “Of all the sciences cultivated by mankind, Astronomy is acknowledged to be, and undoubtedly is, the most sublime, the most interesting, and the most useful. For, by knowledge derived from this science, not only the bulk of the Earth is discovered, but our very faculties are enlarged with the grandeur of the ideas it conveys, our minds exalted above their low contracted prejudices.” - James Ferguson

  22. #52
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    A foreground planet wouldn't have the weird aperiodic effect. Apart from the question of why we've only seen one star affected like this, a cloud of debris in the foreground would have to have just the right overall motion to stay between us and this star for the duration of the Kepler observations...which seems implausible.

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    Speculating of course. I think the concept that a civilisation might add new units to any energy collecting process and projects in an ad hoc fashion more credible than a huge Dyson sphere, which would be way more advanced. So the weird periodicity would make sense where they keep adding new units. If we think about ourselves and we advanced enough to send smaller solar gathering units near the sun we would probably do it incrementally, either based on resources or the need for more energy generation as time goes by. I doubt we would suddenly jump to the stage where we can build some huge dyson sphere before having employed far more modest projects.
    Last edited by Jetlack; 2015-Oct-16 at 10:54 AM. Reason: spelling

  24. #54
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    Quote Originally Posted by Fiery Phoenix View Post
    If you're suggesting that a number of rogue planets are perfectly aligned with us and the star such that they dim its light output by 20%+, then that strikes me as an impossibly low probability. It's an interesting thought nonetheless.
    I don't know how many would be enough for a 20% dip, but I was thinking 2 or 3 orbiting* each other would create weird timing. They would have to be coming directly at us, and even then I would think they would eventually drift off to one side or the other and the dips would stop.

    It is cool, but I think you'd need a lot more mass to get to 20%.

    *Edit - This is a simple arrangement of bodies, but boy would they have to be aligned exactly on the path between us and that star. I like it because it is "sloppy" and the universe does "sloppy" well, but they would have to be in a serious "sweet spot" not to be obvious foreground objects and orbiting each other so that they don't consistently block the light. That alignment doesn't even answer how does such a system block so much light.
    Last edited by Solfe; 2015-Oct-16 at 11:27 AM.
    Solfe

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    If this is a massive ET construct of some type then it wouldn't be too far fetched to say that they have surely known about us for a very long time now.

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    Quote Originally Posted by Spacedude View Post
    If this is a massive ET construct of some type then it wouldn't be too far fetched to say that they have surely known about us for a very long time now.
    I'm not sure since we aren't doing anything so detectable. They can't have picked up our radio waves yet, and if they were looking at us with telescopes then they'd be looking at us circa 500 AD. But they might have known earth has a viable biosphere?

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    This reminds me of the days following the announcement of Cold Fusion. I was working at Princeton University at the time, and listening to the water-cooler speculation was exciting and fun, even though it all turned out to be quite wrong.

    OT: My favorite speculation from when results were not being duplicated was, "Maybe it only works at high altitudes. That could really upset the world's energy/economic/political system."
    I may have many faults, but being wrong ain't one of them. - Jimmy Hoffa

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    Quote Originally Posted by Jetlack View Post
    I'm not sure since we aren't doing anything so detectable. They can't have picked up our radio waves yet, and if they were looking at us with telescopes then they'd be looking at us circa 500 AD. But they might have known earth has a viable biosphere?
    It's not impossible 'they' - if it is a 'they' and not an odd natural phenomena - may be monitoring every viable biosphere in the neighbourhood. Or...not. Or anything in between. the time lag works both ways - they may have died out through some war or disaster, or just moved somewhere else in the last 1500 years.

    At the least we seem to have found an interesting astrophysical phenomena that will hopefully teach us something about the universe we might otherwise not have known

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    Quote Originally Posted by Spacedude View Post
    If this is a massive ET construct of some type then it wouldn't be too far fetched to say that they have surely known about us for a very long time now.
    The Earthlight reaching that system now is from the 5th century.

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    Quote Originally Posted by marsbug View Post
    It's not impossible 'they' - if it is a 'they' and not an odd natural phenomena - may be monitoring every viable biosphere in the neighbourhood. Or...not. Or anything in between. the time lag works both ways - they may have died out through some war or disaster, or just moved somewhere else in the last 1500 years.

    At the least we seem to have found an interesting astrophysical phenomena that will hopefully teach us something about the universe we might otherwise not have known
    Yes maybe those are their generation ships fuelling up for their journey to colonise earth . Yes it will probably end in a huge anti/climax for us but its fun to think "it could be" in the mean time.

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