Instead, they may be the leftover wreckage of a binary star system, making this the first confirmed case of two supernova remnants traced to the same stellar pair. "We weren't really looking for a binary supernova remnant," study first author Miltiadis Michailidis , an astrophysicist and postdoctoral fellow at Stanford University, told Live Science. A dense cloud of hydrogen gas helped astronomers uncover clues that two neighboring supernova remnants may share the same origin. In other words, it's highly likely that the two supernova remnants are related. That finding is consistent with one star in a binary pair going supernova first, with its companion following suit long afterward.