SPACE/COSMOS
Cosmic anomaly hints at frightening future for Milky Way
Royal Astronomical Society
image:
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.
view moreCredit: Bagchi and Ray et al/Giant Metrewave Radio Telescope
A terrifying glimpse at one potential fate of our Milky Way galaxy has come to light thanks to the discovery of a cosmic anomaly that challenges our understanding of the universe.
An international team of astronomers led by CHRIST University, Bangalore, found that a massive spiral galaxy almost one billion light-years away from Earth harbours a supermassive black hole billions of times the Sun’s mass which is powering colossal radio jets stretching six million light-years across.
That is one of the largest known for any spiral galaxy and upends conventional wisdom of galaxy evolution, because such powerful jets are almost exclusively found in elliptical galaxies, not spirals.
It also means the Milky Way could potentially create similar energetic jets in the future – with the cosmic rays, gamma rays and X-rays they produce wreaking havoc in our solar system because of increased radiation and the potential to cause a mass extinction on Earth.
A re-think of galaxy 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," said lead author Professor Joydeep Bagchi, of CHRIST University, Bangalore.
"If a spiral galaxy can not only survive but thrive under such extreme conditions, what does this mean for the future of galaxies like our own Milky Way?
"Could our galaxy one day experience similar high-energy phenomena that will have serious consequences for the survival of precious life in it?"
In the new study, which has been published in Monthly Notices of the Royal Astronomical Society, researchers unravelled the structure and evolution of the spiral galaxy 2MASX J23453268−0449256, which is three times the size of the Milky Way.
Using observations from the Hubble Space Telescope, the Giant Metrewave Radio Telescope, the Atacama Large Millimeter Wave Array and multi-wavelength analyses, they detected an enormous supermassive black hole at its heart and radio jets that are among the largest known for any spiral galaxy, making it a rare phenomenon.
Traditionally, scientists believed that the violent activity of such colossal jets of supermassive black holes would disrupt the delicate structure of a spiral galaxy.
Yet, against all odds, 2MASX J23453268−0449256 has retained its tranquil nature with well-defined spiral arms, a luminous nuclear bar, and an undisturbed stellar ring – all while hosting one of the most extreme black holes ever observed in such a setting.
Adding to the enigma, the galaxy is surrounded by a vast halo of hot, X-ray-emitting gas, providing key insights into its history. While this halo slowly cools over time, the black hole's jets act like a cosmic furnace, preventing new star formation despite the presence of abundant star-making material.
How this compares to Milky Way
Our own Milky Way has a 4 million solar mass black hole – Sagittarius A (Sgr A*) – at its centre, but this is currently in an extremely quiet and dormant state.
That could change if a gas cloud, star, or even a small dwarf galaxy were to be accreted (effectively eaten), the researchers said, potentially triggering significant jet activity. Such events are known as Tidal Disruption Events (TDE) and several have been observed in other galaxies, but not in the Milky Way.
If large jets like this were to emerge from Sgr A*, their impact would depend on their strength, direction, and energy output, the researchers said.
One pointed near our solar system could strip away planetary atmospheres, damage DNA and increase mutation rates because of radiation exposure, while if Earth were exposed to a direct or nearby jet, it could degrade our ozone layer and lead to a mass extinction.
A third possibility is that a powerful jet could alter the interstellar medium and affect star formation in certain regions, which is what has happened in the galaxy the new paper focused on.
Astronomers believe the Milky Way likely had large-scale radio jets in the past and although it could potentially generate them again in the future, experts aren't able to say exactly when because it depends on many factors.
Dark matter clues
The team of researchers also discovered that J23453268−0449256 contains 10 times more dark matter than the Milky Way, which is crucial for stability of its fast spinning disc.
By revealing an unprecedented balance between dark matter, black hole activity, and galactic structure, the experts said their study opens new frontiers in astrophysics and cosmology.
"Understanding these rare galaxies could provide vital clues about the unseen forces governing the universe – including the nature of dark matter, the long-term fate of galaxies, and the origin of life," said co-author Shankar Ray, a PhD student at CHRIST University, Bangalore.
"Ultimately, this study brings us one step closer to unravelling the mysteries of the cosmos, reminding us that the universe still holds surprises beyond our imagination."
ENDS
Media contacts
Sam Tonkin
Royal Astronomical Society
Mob: +44 (0)7802 877 700
Dr Robert Massey
Royal Astronomical Society
Mob: +44 (0)7802 877 699
Scientific contacts
Professor Joydeep Bagchi
CHRIST University, Bangalore
joydeep.bagchi@christuniversity.in
Suraj Dhiwar
Inter-University Centre for Astronomy and Astrophysics
Images and captions
Colossal radio jets in massive spiral galaxy
Caption: 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
J23453268-0449256 vs Milky Way
Caption: Colour image of J23453268-0449256, which is 300,000 light-years across, as captured by the Hubble Space Telescope. It is shown alongside a depiction of our own Milky Way galaxy, which is three times smaller.
Credit: Bagchi and Ray et al/Hubble Space Telescope
Further information
The paper ‘Unveiling the bulge–disc structure, AGN feedback, and baryon landscape in a massive spiral galaxy with Mpc-scale radio jets’ by Joydeep Bagchi and Shankar Ray et al. has been published in Monthly Notices of the Royal Astronomical Society. DOI: 10.1093/mnras/staf229
Notes for editors
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Colour image of J23453268-0449256, which is 300,000 light-years across, as captured by the Hubble Space Telescope. It is shown alongside a depiction of our own Milky Way galaxy, which is three times smaller.
Credit
Bagchi and Ray et al/Hubble Space Telescope
Journal
Monthly Notices of the Royal Astronomical Society
Method of Research
Observational study
Subject of Research
Not applicable
Article Title
Unveiling the bulge–disc structure, AGN feedback, and baryon landscape in a massive spiral galaxy with Mpc-scale radio jets’
Article Publication Date
20-Mar-2025
NASA to launch three rockets from Alaska in single Aurora experiment
NASA/Goddard Space Flight Center
Three NASA-funded rockets are set to launch from Poker Flat Research Range in Fairbanks, Alaska, in an experiment that seeks to reveal how auroral substorms affect the behavior and composition of Earth’s far upper atmosphere.
The experiment’s outcome could upend a long-held theory about the aurora’s interaction with the thermosphere. It may also improve space weather forecasting, critical as the world becomes increasingly reliant on satellite-based devices such as GPS units in everyday life.
The University of Alaska Fairbanks (UAF) Geophysical Institute owns Poker Flat, located 20 miles north of Fairbanks, and operates it under a contract with NASA’s Wallops Flight Facility in Virginia, which is part of NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
The experiment, titled Auroral Waves Excited by Substorm Onset Magnetic Events, or AWESOME, features one four-stage rocket and two two-stage rockets all launching in an approximately three-hour period.
Colorful vapor tracers from the largest of the three rockets should be visible across much of northern Alaska. The launch window is March 24 through April 6.
The mission, led by Mark Conde, a space physics professor at UAF, involves about a dozen UAF graduate student researchers at several ground monitoring sites in Alaska at Utqiagvik, Kaktovik, Toolik Lake, Eagle, and Venetie, as well as Poker Flat. NASA delivers, assembles, tests, and launches the rockets.
“Our experiment asks the question, when the aurora goes berserk and dumps a bunch of heat in the atmosphere, how much of that heat is spent transporting the air upward in a continuous convective plume and how much of that heat results in not only vertical but also horizontal oscillations in the atmosphere?” Conde said.
Confirming which process is dominant will reveal the breadth of the mixing and the related changes in the thin air’s characteristics.
“Change in composition of the atmosphere has consequences,” Conde said. “And we need to know the extent of those consequences.”
Most of the thermosphere, which reaches from about 50 to 350 miles above the surface, is what scientists call “convectively stable.” That means minimal vertical motion of air, because the warmer air is already at the top, due to absorption of solar radiation.
When auroral substorms inject energy and momentum into the middle and lower thermosphere (roughly 60 to 125 miles up), it upsets that stability. That leads to one prevailing theory — that the substorms’ heat is what causes the vertical-motion churn of the thermosphere.
Conde believes instead that acoustic-buoyancy waves are the dominant mixing force and that vertical convection has a much lesser role. Because acoustic-buoyancy waves travel vertically and horizontally from where the aurora hits, the aurora-caused atmospheric changes could be occurring over a much broader area than currently believed.
Better prediction of impacts from those changes is the AWESOME mission’s practical goal.
“I believe our experiment will lead to a simpler and more accurate method of space weather prediction,” Conde said.
Two two-stage, 42-foot Terrier-Improved Malemute rockets are planned to respectively launch about 15 minutes and an hour after an auroral substorm begins. A four-stage, 70-foot Black Brant XII rocket is planned to launch about five minutes after the second rocket.
The first two rockets will release tracers at altitudes of 50 and 110 miles to detect wind movement and wave oscillations. The third rocket will release tracers at five altitudes from 68 to 155 miles.
Pink, blue, and white vapor traces should be visible from the third rocket for 10 to 20 minutes. Launches must occur in the dawn hours, with sunlight hitting the upper altitudes to activate the vapor tracers from the first rocket but darkness at the surface so ground cameras can photograph the tracers’ response to air movement.
By Rod Boyce
University of Alaska Fairbanks Geophysical Institute
NASA Media Contact: Sarah Frazier
Method of Research
Experimental study
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