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[Cthulhu]

I dunno, I'm not sure he meant it like that.  It's not a rogue planet or a dwarf star because those have very distinctive profiles and we would know if that was it. 

It's not something we've observed before which might be what he meant, rather than it being a novel form of matter like dark matter or something.  The most likely explanation I heard was a comet that got too close and is giving off a huge coma as it disintegrtes.  Which would probably be sufficient to cause what we're seeing.  But that's not as cool as a dyson structure.

[origamiscienceguy]

maybe there just happens to be a thick dust cloud between here and there. Not part of the same system, but just right smack in between us.

[Cthulhu]

As I read it I think the issue is that the occlusion is periodic, it keeps happening on a schedule.

[origamiscienceguy]

As I read it I think the issue is that the occlusion is periodic, it keeps happening on a schedule.

The parallax is shifting the dust cloud in relation to the star maybe.

[RedKing]

As I read it I think the issue is that the occlusion is periodic, it keeps happening on a schedule.

As I read it, that was actually part of the problem -- it's NOT periodic. There's one relatively minor pattern of oscillation but then there's these huge dips in brightness that don't have a pattern at all (or the pattern is so complex that it appears chaotic).

I'm really fascinated now, having recently read The Three-Body Problem, where core to the plot is the idea that seemingly chaotic systems can actually be predicted, it just takes very fine-tuned algorithms and a sufficient understanding of the starting conditions.

Wonder if it could be a multi-stellar system with several companion stars in tight orbits around the primary, their intersecting gravitational fields creating wildly chaotic orbits but somehow in a long-period stable configuration? *shrug*

[That Wolf]

Its an alien power generator.
We are just shaved neoanderthals still dancing around for a god to tell us what to do and burying our dead.

The black night orbits our planit but nobody acknowedges it, astronauts see ufos then are told to shut up and it is ignored.
Gorillas used to be a myth.

[Nick K]

I think they've ruled out it being any kind of lumps of normal matter, such as rogue planets or brown dwarfs or whatever - even if they didn't radiate at all they'd do things like blocking light from sources behind it.

What?
It's normal matter distributed distinctly abnormally.  Not dark anything.

So far as I know.

Sorry, that wasn't clear, the "it" in my post referred to dark matter. I was answering the "what if dark matter is dyson spheres" post.

[That Wolf]

The burden of disbelief is on you

[mainiac]

Gorillas used to be a myth.

+1

[Egan_BW]

How far away is the thing anyway? Could we just hurl a probe at it and find out in a few hundred years?

[Dutrius]

I've been thinking while at University today. I've realized that building an actual Dyson Sphere wouldn't be particularly smart. Too many inherent problems with a sphere that big. A torus isn't much better.

Yes, you could build one. The reasons I can think of for doing so are:

• Power generation. You capture all the light radiating from the star with photovoltaic panels lining the inside of the thing.
• Living space. In case all the planets in the system aren't large enough to support your population.
• To show off. Hey! Look at us! Look at what we can do!

There are several major problems of building a structure that large:

• Materials required. You'd need to completely extract the metals from several planets and moons to get enough raw materials.
• Comets and asteroids (or any other body on an elliptical/parabolic/hyperbolic trajectory). If you don't spot and stop these things in time, they are going to make life miserable for the repair crews.
• Finally, and this is the biggest problem, Gravity. It will be a major pain to prevent tidal forces from messing with the structure during construction. Even worse, as soon as the structure completely surrounds the star, the net force of gravitational attraction from the star becomes zero, causing the structure to start to drift. What do you think happens if/when the structure drifts into the star it was built around?

You'd think that a civilization capable of building such a structure would have thought of these and decided not to do it.

TL,DR: Don't build a Dyson Sphere (or Torus). Build a Dyson Swarm comprised of many, separate structures instead. Getting them into an inclined orbit is going to be a right pain, though.

How far away is the thing anyway? Could we just hurl a probe at it and find out in a few hundred years?

It would take several orders of magnitude longer than that...

[Starver]

[...]causing the structure to start to drift[..]

s/causing/allowing
(The way I've always thought about it is that you'd be setting it up as a nonstable (i.e. not  stable, not unstable) equilibrium.  Not strictly an energy minima, maxima or inflection, but an isolated plateau, as by the time you get to the edges of this flat part of the graph, you've got the shell touching the star (and vice-versa) and other problems to deal with.  Should be 'easy' enough to keep nudging it to get rid of perturbations, if you're already a shell/swarm-building civilisation.  Or would the pressure of the incident solar winds already be able to help you out?)

How far away is the thing anyway? Could we just hurl a probe at it and find out in a few hundred years?

It would take several orders of magnitude longer than that...

To put some hard figures into it, the star is 1,480 light-years away.  That's 1480 years it would take for the probe's signal to get back to us.  But first you need to get the probe there in the first place.

Something launched similar to Voyager 1 would (at its current speed) take over 26 million years to get there, if I've not slipped an order or two up or down, by accident.  (New Horizons would be ~34 million years, but then I suppose they wanted to dawdle as much as possible whilst passing Pluto.)

We could probably halve those times, if not more, but it's still millions of years (plus 1,480).  Meanwhile, better telescopes and/or extraordinary scientific breakthroughs in space-transit could make it a redundant mission.  (Or the demise of the human race, by its own hand or otherwise.)

[Il Palazzo]

This is the Kepler data and follow-up analysis paper for that star, referenced by Bad Astonomy and other articles:
Planet Hunters X. KIC 8462852 - Where's the Flux?
http://arxiv.org/abs/1509.03622

Section 4.4.1 provides constraints on the obscuring object.
The rest of section 4.4 provides a number of possible causes analysed by the authors.

To be frank, I don't see how a Dyson sphere fits the bill under those constraints.

Its an alien power generator.
We are just shaved neoanderthals still dancing around for a god to tell us what to do and burying our dead.

The black night orbits our planit but nobody acknowedges it, astronauts see ufos then are told to shut up and it is ignored.
Gorillas used to be a myth.

Oh, for fuck's sake. Folks, we've got another gorilla believer.

[Culise]

There are several major problems of building a structure that large:

• Materials required. You'd need to completely extract the metals from several planets and moons to get enough raw materials.
• Comets and asteroids (or any other body on an elliptical/parabolic/hyperbolic trajectory). If you don't spot and stop these things in time, they are going to make life miserable for the repair crews.
• Finally, and this is the biggest problem, Gravity. It will be a major pain to prevent tidal forces from messing with the structure during construction. Even worse, as soon as the structure completely surrounds the star, the net force of gravitational attraction from the star becomes zero, causing the structure to start to drift. What do you think happens if/when the structure drifts into the star it was built around?

Indeed.  To be fair, the original Dyson sphere was never meant to be a singular solid megastructure; Dyson himself called the notion impossible and considered them a misrepresentation of his original proposals.  Interestingly, if by a Dyson torus you're referring to a ringworld and not a Dyson ring (which is a simple Dyson swarm, but you mention it in contrast to such instead of equating the two), the eponymous Ringworld did eventually consider all of these, if I recall properly, two of them to power plot drama.  Its home system was largely devoid of larger bodies, having been rendered down to create the megastructure.  Defense systems were emplaced to protect against incoming meteorites too small to completely clear out, and with traffic control no longer available to clear the Lying Bastard (the protagonists' ship) for entry, it is mistaken for a potential impactor and shot down on approach.  The problem with the gravitationally-neutral nature of the structure required another book to help resolve it because it was the big one Niven missed, where people stealing the reaction jets that stabilized the structure caused it to drift exactly as it should, absent outside intervention. 

There was also one more interesting thing not likely to occur to the creators of such a megastructure - the societal collapse trap.  Right now, if society collapsed utterly on Earth due to some unspecified cataclysm, we would have an extremely difficult time reconstructing.  Most "easy" veins of iron, copper, coal, oil, or the like have been tapped or utterly depleted as of the present.  A society that needs to rebuild everything from scratch, including methods of resource extraction, will have sizable difficulties in reaching what we've left behind.  A ringworld, Alderson disc, or solid Dyson sphere, however, will have none of these at all unless they're explicitly added by the constructors.  In other words, where we would have an, a post-apocalyptic civilization on a Ringworld would find it even more difficult, if not impossible, to rebuild to anything close to their former glory, unless they get very lucky with what tools and knowledge survives (and don't accidentally dig a hole through the world or the like). 

[monkey]

Our  most  promising  theory  invokes  a  family  of  exocomets.
One way we imagine such a barrage of comets could be triggered
is by the passage of a field star through the system. And, in fact,
as discussed above, there is a small star nearby (~1000AU; Sec-tion 2.3)
 which, if moving near to KIC 8462852, but not bound to
it,  could  trigger  a  barrage  of  bodies  into  the  vicinity  of  the  host
star. On the other hand, if the companion star is bound, it could
be pumping up comet eccentricities through the Kozai mechanism.
Measuring the motion/orbit of the companion star with respect to
KIC 8462852 would be telling in whether or not it is associated, and
we would then be able to put stricter predictions on the timescale
and  repeatability  of  comet  showers  based  on  bound  or  unbound
star-comet  perturbing  models.  Finally,  comets  would  release  gas
(as well as dust), and sensitive observations to detect this gas would
also test this hypothesis.

That would be quite a view.
My money is on the Death Star blowing up Alderaan.