Double supernova remnant DEM L316, X-ray image. It is thought the smaller (top left) of the two supernovae formed from the explosion of a white dwarf star, while the larger supernova formed from the explosion of a massive normal star. Data from the Advanced CCD Imaging Spectrometer on the Chandra X-ray Observatory. DEM L316 lies around 160,000 light years from Earth in the Large Magellanic Cloud galaxy. Data from the Advanced CCD Imaging Spectrometer on the Chandra X-ray Observatory.