This image of Cassiopeia A, the remnant of a stellar explosion, is shown as a brilliant, glowing sphere of hot gas. The dominant colors are various shades of orange and yellow, which represent the intensity of the X-rays that NASA's Chandra X-ray Observatory detected of the exploded star's debris. The structure consists of a bright, semi-circular outer shell with wispy, clumpy filaments radiating around the interior, and a tiny, bright central point. These features create a sense of dynamic energy and motion. This image was the official first light image for Chandra.