Illustration of Ripples in Perseus (IMAGE) Royal Astronomical Society Caption The sound waves (ripples) in the hot gas that fills the Perseus cluster are shown in this artist’s impression. They are thought to have been generated by cavities blown out by jets from a supermassive black hole (bright white spot) at the centre of the galaxy. Credit NASA/NASA/CXC/M.Weiss Usage Restrictions No restrictions. License Public Domain Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.