Astronomers have just witnessed something once thought to be purely theoretical: a star exploding while in close contact with a black hole. The discovery, made possible by AI-powered sky monitoring, may reshape our understanding of how massive stars die.
This groundbreaking event—called SN 2023zkd—was spotted by the Zwicky Transient Facility in July 2023. Located 730 million light-years away, it immediately drew attention from telescopes around the globe.
This rapid response was thanks to ZTF’s algorithmic system, which automatically detects “unusual” cosmic events and sends instant alerts to observatories worldwide—allowing scientists to act fast when every second counts.
A strange kind of supernova
At first, it looked like a standard supernova: a giant star exploding in a brilliant flash, then slowly fading.
© Sirinya, Adobe Stock (image created by AI)
But then something unexpected happened. Months later, the star’s brightness returned—long after it should’ve been dead. Going deeper into the archives, researchers discovered another surprise: the star had also flared dramatically four years before it exploded, a very rare behavior.
The black hole trigger theory
So what caused it? Scientists propose two possible scenarios—and both involve a black hole.
The leading theory is that the star had been caught in orbit around a black hole for years. During that time, the black hole siphoned gas from the star, heating it and causing it to glow brighter as the material approached relativistic speeds. Eventually, the black hole’s gravitational pull destabilized the star so much that it collapsed and exploded.
Spectral analysis even revealed two large outbursts before the final event.
The second, less likely possibility is that the black hole caused the star’s destruction before it could go supernova on its own.
In either case, the black hole appears to have acted like a cosmic detonator—pushing the star to its end.
The first of many cosmic clues?
Until now, this kind of interaction had only been predicted on paper. But this time, the data suggests we might have witnessed it in real time. Astronomers already knew that massive stars in binary systems could influence each other, but here, the exchange of mass happened right before the explosion—and we caught it.
Combination of a Hubble Space Telescope image of SN 1987A and a James Webb Space Telescope image showing a compact, pale blue argon source in the center, detected with the JWST/NIRSpec instrument. © Hubble Space Telescope WFPC-3-James Webb Space Telescope NIRSpec/J. Larsson
And this might just be the beginning. With the new Vera C. Rubin Observatory and ever-smarter algorithms, scientists may soon spot more of these brief, brilliant events. Watching stars live—and die—could become a lot more common in the AI era.
Hugo Ruher
Science journalist
Science journalist, I am above all passionate about space, which is what inspired me to pursue this specialty. Drawn to science in general, I also closely follow news related to the environment and technology.
After earning a degree from Sciences Po Toulouse, I began working in radio, covering general news, international issues, and even local problems. At the same time, I started a career as a science journalist, first focusing on space and later on environmental topics.
Making complex information simple
A large part of my work involves reading scientific studies published in various journals, texts that are often complex or downright indigestible! My goal is to extract information from them and make it accessible to a broader, non-expert audience. This ambition is what truly drives me.
This path has led me to write for teen magazines like Cosinus, highly specialized publications such as Industrie & Technologies, as well as more mainstream outlets like Numerama or Le Monde.
In addition to that, I also sometimes write about topics that are a bit more “lightweight.” The digital world, ranging from the use of social media to AI, and even the culture around video games—are areas that I find fascinating and worth covering with a serious approach.
