Roughly every second, somewhere in our observable universe, another sun is destroyed in a stellar catastrophe—when a star pulsates, collides, collapses to a black hole or explodes as a supernova. This dynamic side of the universe, lost in the apparent calm of the night sky, has lately come to the forefront of astronomical research. For almost a century scientists have tried to trace what has happened over billions of years of cosmic evolution, but it is only recently that we have begun to parse celestial events on timescales of days and hours and so witness the volatile lives and deaths of stars.