A team of scientists using long observations from NASA’s Chandra X-ray Observatory has suggested a massive star that became the Cassiopeia A supernova remnant may have turned inside out as it exploded. An artist's illustration of inner layers of the star that formed Cassiopeia A just before the explosion (left) and distribution of iron, sulfur and magnesium in the supernova remnant (NASA /CXC /M.Weiss / GSFC / U.Hwang / J.Laming) The new...
