The Space Telescope Imaging Spectrograph (STIS) simultaneously records, in unprecedented detail, the velocities of hundreds of gas knots streaming at hundreds of thousands of miles (or kilometres) per hour from the nucleus of NGC 4151, thought to house a supermassive black hole.

This is the first time the velocity structure in the heart of this object, or similar objects, has been mapped so vividly this close to its central black hole.

Credit: John Hutchings (Dominion Astrophysical Observatory), Bruce Woodgate (GSFC/NASA/ESA), Mary Beth Kaiser (Johns Hopkins University), Steven Kraemer(Catholic University of America), and the STIS Team