If the universe has one lesson for humanity, it is that everything ends. That includes stars, which too must die, albeit on timescales of billions of years. But new research suggests that when some stars die, they do not do so alone, potentially solving a long-standing mystery around a particular class of cosmic explosion called an interacting supernova.
When stars much more massive than the sun reach the ends of their lives, their cores collapse, sending shockwaves blasting out into their outer layers, triggering explosions called supernovas and leaving behind stellar remnants in the form of neutron stars or black holes. Interacting supernovas differ because the shockwave generated by these explosions crash into a pre-existing cocoon of material. The big mystery has always been: where does this cocoon of gas and dust come from?
