Mystery of 'Alien Megastructure' Star Testing Astronomers' Creativity

Astronomers may have to think a little harder to solve the mystery of Boyajian's star. NASA's planet-hunting Kepler space telescope spotted these dimming events. Researchers have come up with many possible causes for the dimming, including a swarm of broken-apart comet fragments, variability in the activity of the star itself, a cloud of some sort in the interstellar medium between Kepler and Boyajian's star, and, most famously, an orbiting "megastructure" built by an alien civilization to colle