Active galaxy features, illustration. Active galaxies are those with an active galactic nucleus (AGN), driven by a central supermassive black hole. AGNs emit a range of non-stellar radiation, including radio, microwave, infrared, optical, ultra-violet, X-ray and gamma ray radiation. At top left, the features include a bright core and a dust ring. The diagram at top right shows the dust ring (cloudy), an accretion disc (white), the central supermassive black hole, and a tangled magnetic field. At bottom left, the edge-on view shows the relativistic jets, which are beams of ionised matter accelerated close to the speed of light, as well as radio-emitting lobes at the end of the jets. The face-on view at bottom right is the view seen from Earth. The central two diagrams contrast a 'brilliant' star-like core (left) and a (less energetic) 'bright' star-like core (right).