Image by Kerihobo.
While everybody is discussing the tantalizing possibility that this far off star with its strange dimming patterns hosts an alien megastructure, perhaps a Dyson Sphere under construction, there are even more exotic scenarios out there.
For instance, why not the ruins of one? One of the obvious (if pessimistic) solutions to the Fermi Paradox is that space is a war of all against all, with every surviving alien civilization soon realizing that they can’t afford to show their head above the cosmic parapets. Due to the vast distances involved across space and time, stealth is surely the decisive factor in space warfare, so the offensive reigns supreme over the defensive. Chuck a big, cool clump of dense matter at a very high velocity into a location where it is likely to intersect with the path of a rival space civilization and the guys at the receiving end would hardly have any time to know what hit them let alone where it came from.
It is thus possible that xenocidal aggressiveness is an evolved behavior across all surviving alien civilizations. Just as any good or trusting creature dreamt up by mortals and given flesh in the northern Chaos Wastes of the world of Warhammer gets instantly killed by stronger and more evil entities, so too, perhaps, the less paranoid and aggressive space civilizations get snuffed out as soon as they make their existence known to the cruel gods of the heavens.
Or maybe, Nick Bostrom is correct and we are living in a simulation – with the catch that computing resources are limited and cannot support more than a certain number of superintelligent civilizations and their subsimulations, to say nothing of some kind of Kurzweilian “the universe wakes up” intelligence saturation scenario. Maybe that explains the “supervoid.” A singularitarian civilization attempted to “wake up” the universe in an expanding radius from its home planet, and got their section of space Ctrl-Alt-Deleted by The Architect for their trouble. Since then, other advanced civilizations logically deducated what must have happened, and universally agreed – without any consultation, naturally – to adopt the Lannisterian code that everyone who isn’t us is an enemy.
Or maybe the very observation of KIC 8462852 at this moment in history is an elaborate trap. For instance, here is a particularly paranoid but not implausible scenario from a comment to a Less Wrong article by the Russian futurist Alexey Turchin on the risks of passive SETI:
A comment by JF: For example the lack of SETI-attack so far may itself be a cunning ploy: At first receipt of the developing Solar civilization’s radio signals, all interstellar ‘spam’ would have ceased, (and interference stations of some unknown (but amazing) capability and type set up around the Solar System to block all coming signals recognizable to its’ computers as of intelligent origin,) in order to get us ‘lonely’ and give us time to discover and appreciate the Fermi Paradox and even get those so philosophically inclined to despair desperate that this means the Universe is apparently hostile by some standards. Then, when desperate, we suddenly discover, slowly at first, partially at first, and then with more and more wonderful signals, the fact that space is filled with bright enticing signals (like spam). The blockade, cunning as it was (analogous to Earthly jamming stations) was yet a prelude to a slow ‘turning up’ of preplanned intriguing signal traffic. If as Earth had developed we had intercepted cunning spam followed by the agonized ‘don’t repeat our mistakes’ final messages of tricked and dying civilizations, only a fool would heed the enticing voices of SETI spam. But now, a SETI attack may benefit from the slow unmasking of a cunning masquerade as first a faint and distant light of infinite wonder, only at the end revealed as the headlight of an onrushing cosmic train…
Or maybe it really is something very banal, like a cloud of disintegrating comets…