Dying radio galaxies reveal new insights into black hole jet lifecycles

Astronomers have identified a group of faint “dying” radio galaxies that may alter current scientific understanding of the lifecycle of supermassive black holes. Research led by the University of Cape Town and the Inter-University Institute for Data Intensive Astronomy suggests that the final stage of these galaxies, occurring after central jets stop supplying energy to plasma lobes, is shorter and more active than previously estimated.

Using observations from various radio telescopes, including South Africa’s MeerKAT, researchers investigated 14 galaxy candidates. They confirmed 12 as genuine “remnant radio galaxies,” while two remained active. The confirmed remnants were found to be surprisingly young, with estimated ages ranging from 8 million to 42 million years and a typical age of approximately 12 million years.