By Ron Cowen
Even if astronomers don’t quite know how stars blow up, they thought that they at least understood what those stellar explosions leave behind. But an X-ray–emitting object at the heart of a young supernova remnant called RCW 103 doesn’t fit the textbook view.
Its slow rotation, as well as an outburst that has yet to completely fade after 6 years, make this remnant “absolutely unique among this type of object,” says Gordon Garmire of Pennsylvania State University in University Park. Garmire and his colleagues, as well as a team in Italy, report some unexpected properties of the remnant.