Tabby’s Star – also known as KIC 8462852 or the “alien megastructure” star – is at it again. And this time the world is watching. The star in the constellation Cygnus has intrigued astronomers for a year and a half because they can’t quite explain why it periodically dims. One hypothesis is that aliens are building an energy-generating Dyson sphere around the star, but less way-out possibilities include cometary storms or blobs of circumstellar material. This week, a team on the Canary Islands detected unusual readings from Tabby’s Star, just in time to alert fellow astronomers around the world to turn their telescopes toward it. At last report, the star was registering a sharp 2 to 3 percent dip in brightness – and astronomers are hopeful that a wealth of spectral readings will help them solve the mystery.
— Tabetha Boyajian (@tsboyajian) May 19, 2017