Astronomers have observed a supermassive black hole in galaxy J1007+3540 restarting powerful jets after nearly 100 million years of inactivity. The jets, distorted by intense pressure from a surrounding galaxy cluster, stretch nearly a million light-years. The findings reveal cycles of black hole activity shaping the galaxy's structure.
In galaxy J1007+3540, a supermassive black hole has roared back to life, producing fresh jets of magnetized plasma that clash with the extreme environment of its host galaxy cluster. Radio images from the Low Frequency Array (LOFAR) in the Netherlands and India's upgraded Giant Metrewave Radio Telescope (uGMRT) captured the bright inner jet amid older, fading plasma from prior eruptions. The surrounding cluster's hot gas compresses and warps the jets, particularly the northern lobe, which shows an ultra-steep radio spectrum indicating aged particles have lost energy. A faint tail of emission extends southwest, dragged by the cluster's motion over millions of years.Lead researcher Shobha Kumari of Midnapore City College in India described the event as 'like watching a cosmic volcano erupt again after ages of calm -- except this one is big enough to carve out structures stretching nearly a million light-years across space.' Her team, including Dr. Sabyasachi Pal of the same college, Dr. Surajit Paul of Manipal Centre for Natural Sciences, and Dr. Marek Jamrozy of Jagiellonian University in Poland, published the study in Monthly Notices of the Royal Astronomical Society. Dr. Pal noted, 'J1007+3540 is one of the clearest and most spectacular examples of episodic AGN with jet-cluster interaction, where the surrounding hot gas bends, compresses, and distorts the jets.'The layered structure of young and old plasma highlights repeated black hole outbursts over cosmic timescales. Researchers say such systems provide clues on how black holes cycle between active and quiet phases and how cluster environments influence galaxy evolution. Future observations aim to probe the central region more closely.