Science has many holy grails, but perhaps none as inspiring to the imagination as the possibility of extraterrestrial intelligence. Sure, a perpetual clean energy source or the medical achievement of immortality would be great. But aliens might have already figured such things out, making discovery of them a potential cornucopia of discoveries beyond them.
Recently, astronomers looking for planets in star systems hundreds of lightyears away came across something unusual. From Popular Science:
When a planet passes in front of a star, the star dims only for a few hours or days, and on a regular basis– every 365 days, for example. But, at irregular intervals, the star KIC 8462852 darkens by as much as 20 percent, and it stays dark for anywhere between 5 and 80 days.
What could cause the weird light fluctuations? The researchers who discovered the behavior call it “bizarre.”
One possible explanation is a series of deteriorating comets which irregularly obstruct the star’s light. Then there’s the other possibility.
“Aliens should always be the very last hypothesis you consider,” Penn State astronomer Jason Wright told The Atlantic, “but this looked like something you would expect an alien civilization to build.”
Wright, and many other astronomers, have postulated that we could detect advanced civilizations through their technology. The idea is that as alien civilizations become highly advanced, they’ll need more and more energy to fuel their high-tech lifestyles. Perhaps the aliens would position solar collectors directly around a star, filling the star’s orbit until some or all of its light is blocked. These hypothetical alien megastructures are called Dyson swarms or spheres.
Either scenario seems like a long shot for the real explanation, and we’re not likely to get first-hand evidence clarifying the matter anytime soon.