Chandra X-ray & Hubble Optical Images of Cassiopeia A
This latest study of Cassiopeia A (Cas A) adds to a long collection of Chandra discoveries over the course of the telescope's 20 years. In addition to finding the central neutron star, Chandra data have revealed the distribution of elements essential for life ejected by the explosion, have constructed a remarkable three dimensional model of the supernova remnant, and much more. This still image combines data from Chandra color coded by element, images taken by the Hubble Space Telescope between 2004 and 2011, and additional ground-based images obtained in 1996 and 1999 from the MDM Observatory.
Credit: X-ray: NASA/CXC/SAO; Optical:NASA/STScI

Chandra X-ray Stills from Cas A Time-lapse
A new movie of Cassiopeia A shows how this supernova remnant has changed from 2000 to 2013. The low, medium, and high-energy X-rays detected by Chandra are red, green, and blue respectively as shown in the series of still images that make up the time-lapse movie. The Chandra data shows how 10-million-degree gas is expanding outward after the explosion that destroyed the star.
Credit: X-ray: NASA/CXC/SAO