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The giant radio jets stretching six million light-years across and an enormous supermassive black hole at the heart of spiral galaxy J23453268−0449256, as imaged by the Giant Metrewave Radio Telescope. Credit Bagchi and Ray et al/Giant Metrewave Radio Telescope
Spiral galaxies are often home to some of the most energetic phenomena in the Universe. A supermassive black hole often reside at their core and it is possible that they can generate radio jets, massive streams of plasma and energetic particles that blast outward at nearly the speed of light. These radio jets, often stretch millions of light years across space and are created when material near the black hole is superheated and accelerated creating beams that can dramatically impact the surrounding region of space. While most spiral galaxies contain these central black holes, a handful can produce radio jets so that those which do are closely studied.
LEDA 1313424, nicknamed the Bullseye, is two and a half times the size of our Milky Way (Credit: NASA, ESA)
A team of astronomers from CHRIST University in Bangalore have been studying a spiral galaxy with the catchy name ‘2MASX J23453268−0449256’ nearly one billion light-years away. It’s one that hosts a supermassive black hole billions of times the mass of our Sun and generates a radio jet that stretches out for six million light years. It’s discovery raises questions bout the jet formation process because they are typically associated with elliptical galaxies instead.
It was a surprise to the team that a spiral galaxy with such an active radio jet was able to maintain its spiral structure with well defined spiral arms. The galaxy is surrounded by a vast halo of hot X-ray emitting gas and reveals complex processes where the black hole's powerful jet simultaneously prevents new star formation while preserving the galaxy's shape, and it’s this that challenges our fundamental understanding of galactic evolution.
"This discovery is more than just an oddity – it forces us to rethink how galaxies evolve, and how supermassive black holes grow in them and shape their environments," lead author Professor Joydeep Bagchi, of CHRIST University, Bangalore
M87 taken with the Very Large Array (VLA) radio telescope in February 1989, showing its powerful jets of subatomic particles coming from the the galaxy's central black hole (Credit : National Radio Astronomy Observatory/National Science Foundation)
The researchers published their findings in the Monthly Notices of the Royal Astronomical Society. They combined images of the galaxy, which is three times larger than the Milky Way, from the Hubble Space Telescope, the Giant Metrewave Radio Telescope and the Atacama Large Millimetre Wave Array. It was this data that revealed the immense black hole and radio jets.
The discovery also raises implications for our own Milky Way, suggesting it to has the potential for producing similar energetic jets in the future. It's a scenario that could produce harmful cosmic rays, gamma rays, and X-rays and may even be capable of generating extreme radiation levels and potentially trigger a mass extinction event on Earth!
The Milky Way above Chile (Credit : ESO/Y. Beletsky)
In comparison to our own Milky Way which has a modest and somewhat dormant 4 million solar mass black hole, Sagittarius A*, could potentially become active if it consumes a gas cloud or star cluster or even just a star, triggering a massive radio jet. Such an event could have devastating consequences, including stripping away planetary atmospheres, increasing radiation across the Solar System and potentially causing mass extinction. While astronomers believe such jet activity has occurred in the past and could happen again, the exact timing remains difficult to predict.
Another discovery made by the team reveals that J23453268−0449256 contains ten times more dark matter than the Milky Way! It suggests the dark matter provides a stabilising influence to its rapidly spinning disk. The balance between dark matter may in some way act to stabilise the structure and, as co-author Shankar Ray notes, understanding such rare galaxies could reveal vital clues about the nature of dark matter, and the fundamental processes of galactic formation.
Source : Cosmic anomaly hints at frightening future for Milky Way
Mark Thompson
Science broadcaster and author. Mark is known for his tireless enthusiasm for making science accessible, through numerous tv, radio, podcast and theatre appearances, and books. He was a part of the aware-nominated BBC Stargazing LIVE TV Show in the UK and his Spectacular Science theatre show has received 5 star reviews across UK theatres. In 2025 he is launching his new pocast Cosmic Commerce and is working on a new book 101 Facts You Didn't Know About Deep Space In 2018, Mark received an Honorary Doctorate from the University of East Anglia.
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