A one-of-a-kind supernova was seen exploding — over and over again
In September 2014, when astronomer Iair Arcavi found a new supernova in the night sky, he didn’t think much of it. It looked like any other star that had just died and violently burst apart. The object had brightened some time ago, and now it was fading — a sign that the explosive event was coming to an end. Since the juiciest part seemed to be over, Arcavi abandoned the star in search of supernovae that had exploded more recently.