Phoenix galaxy cluster, composite Chandra X-Ray Telescope, Hubble Space Telescope and Very Large Array (VLA) Telescope image. X-rays from Chandra depict hot gas in purple and radio emissions from the VLA feature jets in red. Optical light data from Hubble show galaxies (yellow), and filaments of cooler gas (light blue) where stars are forming. The central galaxy of the cluster contains a supermassive black hole which is thought to eject the gas jets. As the jets push outward, they create cavities, or bubbles, in the hot gas that pervades the cluster.