The mystery of how Cassiopeia A exploded is unraveling thanks to new data from NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR. In this image, NuSTAR data, which show high-energy X-rays from radioactive material, are colored blue. Lower-energy X-rays from non-radioactive material, imaged previously with NASA's Chandra X-ray Observatory, are shown in red, yellow and green. The new view shows a more complete picture of the remains of a star that blew up in a supernova event whose light reached Earth about 350 years ago. The remnant is located 11,000 light-years away from Earth. Learn more: nasa.gov/nustar Credit: NASA/JPL-Caltech/CXC/SAO #nasa #blackholefriday #blackhole #universe #space #science #nustar