Go to: COOL CASSIE This colorful blob is a supernova remnant known as Cassiopeia A, whose startling structure and color are the result of a considerable technological advance in X-ray imaging. Snapped by the Chandra X-ray Observatory, the X-ray energies of "Cassie A" are depicted in red, green and blue, from lowest to highest intensities. The supernova, located in the constellation Cassiopeia, is 10 light-years across and 10,000 light-years from Earth. (08/21/02)