One astronomer has speculated that it’s encased within a vast alien megastructure, and although scientists have yet to solve that particular stellar mystery, they are continuing to scour the sky in search of these colossal construction projects — both within and beyond our home galaxy.

It might sound like science fiction, but as early as 1959 physicist Freeman Dyson surmised that all advanced civilizations — including ours — would eventually build one of these megastructures. He predicted that any civilization could wake up one day to discover that they had consumed all of the energy available on their home planet. At this point, each civilization would naturally look toward their stars, giant nuclear furnaces that release torrents of energy every second, for a solution. Unfortunately, only a sliver of that energy, in the form of light, will fall on any orbiting planet. Most is simply lost to space. So any advanced civilization would likely build a series of solar panels to envelope the star, almost like scaffolding around a church’s dome, collecting every available scrap of the star’s energy and beaming it back toward their home planet.

Today these megastructures are better known as Dyson Spheres, and from an engineering perspective they sound pretty wild. It’s true that a sphere which completely encloses a star is impractical (one asteroid strike or stellar flare and the entire shell would become unstable) — but a swarm of mirrors that orbit the star like bees buzzing around a hive, or a ring of mirrors that could look as majestic as the rings of Saturn are practical. They’re so practical, in fact, that human beings already have most of the tools to build one.