Chandra’s X-ray image (left panel) of the supernova remnant DEM L71 revealed a ten million-degree hot inner cloud (aqua) of glowing iron and silicon surrounded by an outer ring of 5 million-degree gas. The outer ring is also visible at optical wavelengths (right panel). An analysis of the Chandra data identified the inner cloud as the remains of a white dwarf star that exploded. The white dwarf pulled matter from a nearby companion star onto itself until it became unstable and blew apart in a thermonuclear explosion called a Type Ia supernova.