A nearby cosmic ticking time bomb has been found! Just 150 light years away, a pair of white dwarf stars are on a death spiral, destined to explode in a type 1a supernova.
This discovery confirms long-held theories and could help unlock the secrets behind these dazzling, universe-measuring explosions. Though it won’t go off for 23 billion years, when it does, it’ll outshine the moon and leave a mark on the cosmos.
Rare Stellar Duo Discovered Nearby
Astronomers at the University of Warwick have discovered an exceptionally rare and massive binary star system just 150 light years from Earth. The two stars, a pair of white dwarfs, are locked in a tight orbit and are on track to eventually collide and explode as a type 1a supernova. When it happens, the explosion is expected to shine up to ten times brighter than the full moon in the night sky.
Type 1a supernovae are a unique kind of stellar explosion used by astronomers as “standard candles” to measure distances across the universe. These explosions occur when a white dwarf, the dense core left behind after a star dies, gains too much mass, becomes unstable, and detonates.
Two White Dwarfs, One Fate
For years, scientists have theorized that most type 1a supernovae come from systems with two closely orbiting white dwarfs. In these rare setups, the more massive star gradually pulls material from its companion. As the mass builds, one or both stars eventually explode.
This new discovery, published today (April 4) in Nature Astronomy, marks the first confirmed observation of such a system, and it’s right in our own galactic neighborhood.
This is a movie of the explosion of a double white dwarf binary star system. The simulation was published in Nature Astronomy by James Munday and collaborations in LINK. Full credit goes to Dr. Ruediger Pakmor (Max-Planck-Institut für Astrophysik) for conducting this simulation and authorizing it to be shared. The double white dwarf has the highest total mass known to date, coming in at (1.555+-0.044) times the mass of the Sun. The more massive star that is gaining material has a mass of (0.834+-0.039) solar masses, and the less massive one (0.721+-0.020) solar masses. Credit: Dr. Ruediger Pakmor (Max Planck Institute for Astrophysics)
How the Team Tracked It Down
James Munday, PhD researcher at Warwick and leader of the investigation said, “For years a local and massive double white dwarf binary has been anticipated, so when I first spotted this system with a very high total mass on our Galactic doorstep, I was immediately excited.”
“With an international team of astronomers, four based at The University of Warwick, we immediately chased this system on some of the biggest optical telescopes in the world to determine exactly how compact it is.”
“Discovering that the two stars are separated by just 1/60th of the Earth-Sun distance, I quickly realized that we had discovered the first double white dwarf binary that will undoubtedly lead to a type 1a supernova on a timescale close to the age of the universe.”
“At last, we as a community can now account for a few percent of the rate of type 1a supernovae across the Milky Way with certainty.”
Guaranteed to Explode
Significantly, James’s new system is the heaviest of its type ever confirmed, with a combined mass of 1.56 times that of the Sun. At this high of a mass, this means that, no matter what, the stars are destined to explode.
The explosion is not due for another 23 billion years, however, and despite being so close to our solar system, this supernova will not endanger our planet.
Countdown to Cataclysm
Right now, the white dwarfs are leisurely spiraling around each other in an orbit taking longer than 14 hours. Over billions of years, gravitational wave radiation will cause the two stars to inspiral until, at the precipice of the supernova event, they will be moving so fast that they complete an orbit in a mere 30 – 40 seconds.
Dr. Ingrid Pelisoli, Assistant Professor at The University of Warwick and third author, added: “This is a very significant discovery. Finding such a system on our galactic doorstep is an indication that they must be relatively common, otherwise, we would have needed to look much further away, searching a larger volume of our galaxy, to encounter them.
“Finding this system is not the end of the story though, our survey searching for type 1a supernova progenitors is still ongoing and we expect more exciting discoveries in the future. Little by little we are getting closer to solving the mystery of the origin of type 1a explosions.”
A Rare Quadruple Detonation
For the supernova event, mass will transfer from one dwarf to the other, resulting in in a rare and complex supernova explosion through a quadruple detonation. The surface of the mass-gaining dwarf detonates where it is accumulating material first, causing its core to explode second. This ejects material in all directions, colliding with the other white dwarf, causing the process to repeat for a third and fourth detonation.
The explosions will completely destroy the entire system, with energy levels a thousand trillion trillion times that of the most powerful nuclear bomb.
A Brilliant Finale
Billions of years into the future, this supernova will appear as a very intense point of light in the night sky. It will make some of the brightest objects look faint in comparison, appearing up to ten times brighter than the moon and 200,000 times brighter than Jupiter.
Reference: “A super-Chandrasekhar mass type Ia supernova progenitor at 49 pc set to detonate in 23 Gyr” by James Munday, Ruediger Pakmor, Ingrid Pelisoli, David Jones, Snehalata Sahu, Pier-Emmanuel Tremblay, Abinaya Swaruba Rajamuthukumar, Gijs Nelemans, Mark Magee, Silvia Toonen, Antoine Bédard and Tim Cunningham, 4 April 2025, Nature Astronomy.
DOI: 10.1038/s41550-025-02528-4
James Munday was supported by funding from a Science and Technology Facilities Council (STFC) studentship. Ingrid Pelisoli acknowledges support from The Royal Society through a University Research Fellowship (URF/R1/231496)
Never miss a breakthrough: Join the SciTechDaily newsletter.
Follow us on Google and Google News.
18 Comments
“Though it won’t go off for 23 billion years, when it does, it’ll outshine the moon and leave a mark on the cosmos.”
I was under the impression that in 6 billion years, the Sun will be a red giant engulfing the Earth and the universe is only 13.8 billion years, and the Andromeda galaxy will collide with our Milky Way in 4 to 4 billion years, so this is an exceptionally slow rate of decay, and there won’t be an Earth left to potentially affect and there will not be a Moon to outshine. Still, cool prediction: to predict a decay rate so infinitesimally small is impressive.
I agree! As a Planet and/or it’s people, we either won’t still inhabit Earth or we will have evolved into something else by the time this happens. Our own Sun should be long gone by then. Nice info but useless.
Another factor is that in 23 billion years our sun (or what’s left of it) will have moved too. The distance is not constant likely the distance will be on the order of thousands of light years so it won’t be 10 times as bright as our moon from our location.
Why is money and time being wasted studying useless information about things that are alleged to happen in 23 billion years from now? All this effort would be better put to researching, for example, finding answers to various health problems that are plaguing us right now.
Money does not leave the Earth, nor does it get used up. Any money spent on this research is still circulating in the economy, doing what money does- supporting the lives of countless people like you.
Astronomers don’t study health though and they went to college and paid money to study celestial bodies and how they affect the universe as a general understanding of existence, you should mention that to people who research medicine to make money instead of curing diseases though.
Wrong Humanity is engaged in a quest to find out how the universe, that is everything, ticks. It is part of being human. Seems you would rather sit around having your mind dulled by soap operas
The sun will have orbited the galaxy 100 or so times and be long gone from this pair.
It’s simply stating that for relativity; *if* the Earth were still around, *then* it would appear 10 brighter than then moon. From what I read a planet would have to be at least 160 light-years away from a type 1A supernova to be safe anyway. So this hypothetical “future Earth” 32 billion years from now would also be 10 light-years short of surviving the actual event.
Human life on earth “only” has just shy of 2 billion years to go, at best..
Human life will be something else after 2 million years, the typical timescale for biological evolution…
Humanity is more likely to be extinct long before 2 million years than we are to be still around, let alone evolved or moved to new planets or solar systems.
When Jesus comes and the world won’t end but people will still exist to get righteous with God and Jesus if they are smart enough to refuse the mark of the beast because that’s the only way that money will exist with out it you can’t buy sale nor trade God created the Earth and the universe no big bang explososion
given cosmic expansion (“dark energy”) I suspect the supernova will be a lot farther away than 150 light years in 23 billion years
Do these stars have a name?? I couldn’t find one at all through the whole write up..
The double white dwarf is known as WDJ181058.67+311940.94.
Money spent on investigating the universe isn’t wasted—it’s invested in understanding the fundamental nature of reality. What’s truly impressive is that, with the tiny amount of information we can glean from something 150 light-years away—roughly 900 trillion miles—our models are accurate enough to predict events like neutron star collisions, even if they won’t happen for another 23 billion years. Sure, it would feel more exciting if the collision were happening next week, but the universe doesn’t operate on human time scales.
And this kind of research isn’t just academic. Technologies developed for astronomy often find their way into everyday life. CCD (charge-coupled device) sensors, originally developed to capture faint light from distant stars, are now used in medical imaging tools like endoscopes and digital X-ray systems, where their sensitivity and resolution help doctors detect and diagnose diseases earlier and more accurately.
Do they really mean 23 billion years, is this a mis-print or typing error?