A faraway megastar that once raised questions about aliens because of its weird pattern of dimming has darkened once again.
By now, though, researchers have figured out that it's not an alien megastructure that is causing the dimming; it's just dust. Still, astronomer Tabetha Boyajian of Louisiana State University and colleagues are keeping a close eye on the far-off star, trying to figure out what the dust is and where it came from. On March 16, the brightness of the star started dipping, Boyajian and her colleagues reported on their blog. The dip in brightness was the largest observed dip in the star since 2013, Boyajian wrote.
As of March 22, the star's brightness was increasing rapidly and was almost back to normal.