Chandra Image of Elements from Cas A (IMAGE) Harvard-Smithsonian Center for Astrophysics Caption Astronomers using NASA's Chandra X-ray Observatory have announced the discovery of an important type of titanium blasting out from the center of the supernova remnant Cassiopeia A (Cas A), a result that could be a major advance in understanding how some massive stars explode. The different colors in this new image mostly represent elements detected by Chandra in Cas A: iron (orange), oxygen (purple), and the amount of silicon compared to magnesium (green). Titanium (light blue) detected previously by NASA's NuSTAR telescope is shown, but not the different type of titanium found by Chandra. These X-ray data have been overlaid on an optical-light image from the Hubble Space Telescope (yellow). Credit NASA/CXC/RIKEN/T. Sato et al.; NuSTAR: NASA/NuSTAR Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.