Physicists have coaxed a black hole's most famous glow out of a strand of optical fiber and, for the first time, watched that light react back on the simulated black hole that produced it.

The result gives researchers a rare, hands-on look at Hawking radiation ‪—‬ the faint thermal emission that Stephen Hawking predicted should leak out of black holes ‪—‬ and offers a first clue about the tiny push that could, in principle, make a real black hole slowly evaporate, the research team said in a new study.

Working with a tabletop experiment in optical fibers, the international team detected both the radiation and its long-sought "back reaction" — the way the radiation feeds energy back and reshapes the object that created it.

According to the new study, published July 1 in the journal Nature, the light behaved exactly as Hawking predicted it should: like the glow of a warm object, with a definite temperature and a spectrum that fades away steadily toward higher frequencies. It did so even in a regime where the usual textbook description of a black hole should break down.

Where three great theories collide

Hawking radiation is famous because it sits at the crossroads of physics' biggest ideas.

"Jacob Bekenstein predicted that black holes have an entropy and a temperature, and Hawking calculated the thermal radiation of the black hole," study co-author Ulf Leonhardt, a physicist at the Weizmann Institute of Science in Israel, told Live Science via email. "In Hawking-Bekenstein radiation, quantum physics, general relativity and thermodynamics come together — subjects that are normally in conflict with each other."

The conflict runs deep: General relativity pictures space and time as smooth and continuous, while quantum mechanics describes a world of discrete, unpredictable jumps ‪—‬ and no one has managed to fully reconcile the two.

That combination is exactly what makes Hawking radiation so hard to study. Astronomers have never seen Hawking radiation from a real black hole and probably never will; the glow is far too faint to pick out across the cosmos. So physicists have turned to laboratory stand-ins that obey the same equations, building black hole analogues out of flowing water, ultracold atoms and, as in this study, light.

Building a black hole from light

The trick behind every black hole analogue is a moving medium. "Imagine a swimmer in the sea with a current faster than he can swim," Leonhardt explained. "He is swept away. This is what happens beyond the [event] horizon, and this is why normally nothing can escape the black hole."

A black hole's event horizon is the boundary where that current — space itself, in real life — starts moving faster than anything can travel. To recreate it, the team needed a material that appears to rush along at the speed of light. Their solution was elegant: use light to make the "material."

"In optics we need a material that appears to move at the speed of light," Leonhardt said. "For this we use light itself — in nonlinear optics, light acts like a material."

In practice, the researchers fired an intense, ultrashort "pump" pulse into a thin photonic-crystal fiber — a strand of glass threaded with a pattern of tiny air channels running along its length, which lets researchers fine-tune how light moves through it. As it traveled, the pulse slightly changed how the glass bent light, creating a moving speed bump that raced along with it. A second, much weaker "probe" pulse then ran into this moving front. Where the probe could no longer keep up, an artificial horizon formed — and the black hole analogue was born.

Catching the glow and its pushback

The payoff came in the ultraviolet. According to theory, Hawking radiation is created in pairs: One partner escapes, while the other, carrying "negative" energy, is the mirror image that would fall into a real black hole. In the fiber, that partner showed up as ultraviolet light.

"We counted photons in the ultraviolet that correspond to the Hawking partners beyond the horizon," Leonhardt explained. "They have a wavelength around 233 nanometers. This was our signal."

Just as important as seeing the glow was understanding how it was made. For years, researchers assumed the fiber built up its Hawking radiation through a cascade — a chain of separate steps in which the light is converted first into one intermediate form, and then another, each feeding the next before the radiation finally emerges. The team found that, instead, a single, direct interaction does the job, with the pump and probe light producing the Hawking pair in one clean step. It is a much simpler picture that the researchers said may carry over to other analogues and perhaps even to real black holes.

Because energy has to come from somewhere, making Hawking radiation should nudge the source that created it. For a real black hole, that nudge is how it loses mass and, over unimaginable timescales, evaporates entirely — the process Hawking described in his landmark 1974 paper. No experiment had ever captured that recoil.

Here, the team saw it. Producing the radiation shifted a small fraction of the pump pulse's own light to a slightly different color, leaving a telltale lopsided pattern in the spectrum. That asymmetry, absent in earlier experiments, is the fingerprint of the back reaction, or recoil — the black hole analogue quietly paying the energetic price for its own glow.

The road to a quantum experiment

The result also speaks to one of the thorniest puzzles in black hole physics: the trans-Planckian problem. Trace Hawking's radiation back to where it was born and the calculation runs into territory no physicist can vouch for — the Planck scale, the vanishingly small size at which space and time are thought to lose their familiar meaning and all known physics gives out. Hawking's prediction, in other words, appears to rest on a foundation that may not exist.

"Any light getting away from the horizon is stretched out enormously," Leonhardt said. "So it must come from waves smaller than the tiniest scale in nature, where the physics is unknown. Would that still give Hawking radiation? That was the question, and we have answered it in our experiment." Remarkably, the glow stayed perfectly thermal even in this extreme regime.

The team's next step is concrete. So far, they have used ordinary laser light, which reproduces the spectrum of Hawking radiation but not its deepest quantum weirdness. Next, the team plans to "go quantum," Leonhardt said. "We will explore how to get into the quantum regime and observe quantum features such as entanglement" — the ghostly link that should tie each escaping Hawking particle to its lost partner.

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The European Space Agency's (ESA) Euclid space telescope has spotted 31 previously unknown quasars dating to the universe's earliest chapter, including the two oldest ever found.

The discoveries, described July 6 in the journal Astronomy & Astrophysics, more than double the number of known quasars from that primordial era and could help astronomers unravel one of cosmology's biggest mysteries: how supermassive black holes grew so enormous so quickly after the Big Bang.

"It's a big step towards understanding these fascinating objects on a more fundamental level," Antonio La Marca, an ESA research fellow on the Euclid team, said in a statement.

Quasars are among the brightest objects in the universe. They form when gas and dust spiral into a galaxy's central supermassive black hole, heating up and releasing enormous amounts of energy that can outshine the galaxy itself. Each of the two most ancient quasars detected in the new study shone with the light of a trillion suns, according to the researchers.

Euclid spotted the quasars while surveying the distant universe. Twelve of them have redshifts of 7 or higher, meaning their light has traveled for more than 13 billion years and dates to the universe's first 770 million years. Two of the objects, with redshifts of 7.77 and 7.69, are the most ancient quasars ever identified, shining just 670 million years after the Big Bang, when the universe was only about 5% of its current age.

"These early quasars date back to the Universe's infancy," Daming Yang, an astronomer at Leiden University in the Netherlands and first author of the new study, said in the statement. "By finding and studying them, we can better understand how these enormous systems formed and grew so quickly — one of the greatest mysteries in astrophysics."

Finding quasars from the early universe has long been difficult because they are rare and incredibly distant. Until now, astronomers had identified only the brightest examples, making it difficult to understand the broader population during this early era. Euclid's wide-field survey is changing that by detecting fainter quasars across huge swaths of the sky.

The latest discoveries represent only a fraction of what the telescope is expected to find during its six-year mission, which will cover more than one-third of the total sky once complete. Mounted with a pair of instruments that see in visible and near-infrared light, Euclid is currently assembling the largest-ever 3D map of the universe. Scientists expect the survey to uncover hundreds of similarly ancient quasars, providing an unprecedented look at how the universe's earliest galaxies and supermassive black holes evolved.

Euclid has also taken some time to study the nearby universe, revealing more than 60 million individual stars packed into the Milky Way's center in a sparkling image released in late June.

Black hole quiz: How supermassive is your knowledge of the universe?

Scientists have found evidence that gravitational waves from a spectacular black hole collision carry signals from the very edge of the newly formed black hole. If confirmed by future observations, the discovery could provide an entirely new way to investigate what happens in the immediate vicinity of a black hole without ever observing it directly.

In a new study, the researchers analyzed an exceptionally strong gravitational wave event known as GW250114. They identified a "direct wave," a subtle feature of the total gravitational wave signal predicted by theory but never previously detected in real data. The signal appears to contain information from extremely close to the black hole's event horizon, the boundary beyond which nothing, not even light, can escape.

The findings, published June 24 in the journal Nature, suggest that gravitational wave observatories may eventually allow astronomers to probe regions that have remained inaccessible since black holes were first predicted by Albert Einstein's theory of general relativity.

Listening to the edge of a black hole

Although astronomers have photographed the glowing material surrounding some supermassive black holes and have detected dozens of black hole mergers through gravitational waves, the event horizon itself has remained frustratingly difficult to study.

Unlike ordinary light, gravitational waves are tiny ripples in space-time produced when massive objects accelerate. They pass almost undisturbed through the universe, carrying information about violent cosmic events that would otherwise remain hidden.

According to study co-author Sizheng Ma, a postdoctoral researcher at the Perimeter Institute for Theoretical Physics in Canada, the newly identified signal offers a rare glimpse of what happens immediately after two black holes collide.

"When two black holes merge, they violently shake space-time itself," Ma told Live Science. "For a brief moment, the region very close to the newly formed black hole's horizon is swept into a fast, fading swirl."

Ma explained that the direct wave is the portion of the gravitational wave signal produced near the horizon and carries the imprint of that motion outward through space.

"That is why it is so interesting," he said. "It may let us 'listen' to what happens near the horizon, a region we cannot see directly with light."

A remarkable black hole collision

The team focused on GW250114, a black hole merger detected on Jan. 14, 2025, by the two Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors in Hanford, Washington, and Livingston, Louisiana.

"Our earlier theoretical work predicted that black hole mergers should produce a direct-wave signal from the near-horizon region," Ma said. "The big question was whether this effect could actually be seen in real data."

GW250114 turned out to provide exactly the conditions needed to test that prediction.

"It was strong enough, clean enough, and close enough to the theoretical situation where this signal should be visible," he said.

To search for the elusive feature, the researchers first removed the best-understood part of the gravitational wave signal, which comes from the newly formed black hole settling down after the merger. Then, they examined the remaining data to determine whether it consisted only of detector noise or contained another physical signal.

"What we found was striking," Ma said. "The remaining signal followed the expected rhythm and fading pattern of a wave shaped by the region very close to the final black hole's horizon."

The team concluded that the leftover signal matches the behavior expected for a direct wave predicted by previous theoretical studies.

A new way to explore extreme gravity

The researchers stressed that their findings do not reveal what lies inside a black hole. Instead, they're providing a new observational tool for investigating the region immediately outside the event horizon.

"The gravitational wave data appear to carry an imprint from very close to the newly formed black hole's horizon — the famous point of no return," Ma said.

He explained that the measurements are consistent with space-time near the horizon being rapidly dragged around by the spinning black hole while the signal fades because of the intense gravitational field.

"For us, the exciting message is that gravitational waves may be giving us a new way to study the edge of a black hole using real observational data," Ma said.

Ma believes the method could eventually become useful for exploring ideas such as quantum gravity — which seeks to unite Einstein's theory of gravity with quantum mechanics — or the black hole information paradox, the longstanding puzzle of whether information that falls into a black hole is truly lost. However, it cannot test those questions directly yet.

"If quantum effects, or any deviations from the standard black-hole picture, leave a measurable imprint there, then direct waves could, in principle, help us search for them in the future," he said.

More observations will be needed

The researchers cautioned that the discovery is based on a single gravitational wave event. While GW250114 provided exceptionally favorable conditions, much stronger evidence will come only if similar signals are found in many additional black hole mergers.

"There are two main directions," Ma said. "The first is theory."

Current models capture the essential physics but remain simplified, and more realistic descriptions of black hole mergers will be needed.

"The second is observation," he added. "This result comes from one exceptionally loud and clean event, so the strongest confirmation would come from seeing the same kind of pattern in other black hole mergers."

As gravitational wave observatories continue to improve and detect increasing numbers of mergers, researchers hope to determine whether direct waves are a universal feature of black hole collisions.

"If the pattern appears repeatedly in the way general relativity predicts," Ma said, "direct waves could become a new way to study black hole horizons or the regions very close to them, and to test Einstein's theory in one of the most extreme environments in the universe."

If future observations confirm the team's results, scientists may have gained something they have sought for decades: a direct observational window into the very edge of a black hole.

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A new theoretical study adds fresh support to the idea that a mathematical pattern of ripples in space-time geometry could give rise to naked singularities and microscopic black holes. The new finding advances research into a subject that has vexed physicists for decades.

In 1997, Stephen Hawking famously conceded defeat on a 1991 bet with fellow theoretical physicists Kip Thorne and John Preskill about the possible existence of naked singularities: objects like black holes but without an event horizon (a point beyond which light, and all other matter, cannot escape), making them observable. Hawking eventually admitted that such objects could exist. Thorne and Preskill’s prize? T-shirts to cover their "nakedness."

The evidence that swayed Hawking came from physicist Matthew Choptuik. In 1993, Choptuik studied a specific set of solutions to Albert Einstein's general relativity equations. When solved numerically, on what was then considered a supercomputer, he showed how naked singularities could hypothetically occur under very specific conditions.

Choptuik found that by modeling the gravitational collapse of a simple form of matter, such as a field, and fine-tuning the initial conditions, an unstable state can be constructed. This theoretical state later became known as a space-time crystal — a self-organized repetitive mathematical pattern of ripples in space-time geometry — containing a singularity with infinite curvature (a naked singularity). Because such a singularity wouldn’t form inside a black hole, it could theoretically be observable.

But much like the phase transition from liquid water to ice, this state is delicate, with the field teetering on the edge between dissipating to become empty space or forming a microscopic black hole.

However, significant doubt remained about such a state's existence, even theoretically.

"Whenever you formulate a system in numerical code, you always have a problem because you can only represent a finite number of digits on a computer," study co-author Christian Ecker, an astrophysicist at Goethe University in Germany, told Live Science. "The historic computer simulations could only go so far before inaccuracies became unavoidable."

Though more recent numerical methods offer much higher accuracy, they are not exact and can never provide deep understanding of the phenomenon that traditional analytical methods (such as manipulating equations using algebra and calculus) offer.

In the new study published May 12 in the journal Physical Review Letters, the researchers mathematically described the formation of space-time crystals, naked singularities and microscopic black holes precisely.

A pen and paper solution

They succeeded using just pen and paper, and some mathematical sleight of hand. "Whenever physicists find a small parameter, they are happy because they can first solve the equations when this parameter is zero, then add small corrections to it with standard perturbation theory," co-author Daniel Grumiller, an astrophysicist at the Institute for Theoretical Physics, Vienna University of Technology, told Live Science. "General relativity by itself doesn’t have a small parameter, but if you inject a small parameter [one over the number of dimensions and let this number be huge]… then you can use these perturbative tools and get a handle on otherwise very tough equations."

When taking the number of dimensions to be infinite, the team's exact solution could fit on just a few lines. This solution is unrealistic given we are most certainly not living in an infinite dimensional universe. However, as they brought the number of dimensions down to more realistic numbers, the solution required additional terms that made the expressions ever more complicated.

"The lowest dimension that we can consistently connect with so far is 52, but the numerical data extends only up to dimension 14 — so there's a gap," Grumiller said, referring to the fact that neither pen-and-paper nor numerical techniques are accurate enough to cross paths yet.

"In the future, we plan to extend the numerics to higher dimensions, so that we can actually connect the two," Grumiller added.

Doing so would provide a compelling case that space-time crystals, naked singularities and microscopic black holes are mathematically possible in a universe like ours — however, this would still not prove they actually exist in reality. In the end, Hawking may have awarded those T-shirts too soon.

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The James Webb Space Telescope has spotted the most distant, dormant black hole in the known universe , hiding in a galaxy more than 10 billion light-years from Earth.

The newly analyzed black hole, located in a galaxy called MRG-M0138, smashes the previous distance record for such an object by 15 times, according to a study published Thursday (June 4) in the journal Science.

Studying black holes like this, which formed early in the universe's 13.8-billion-year-old history, will give researchers an unprecedented look at how black holes evolved when the universe was young. Within MRG-M0138, for example, scientists suspect there used to be a quasar (an extremely bright and supermassive black hole) that grew very quickly, eventually throwing out a significant amount of gas in the galaxy needed to form new stars. This process rapidly shut down star formation in the galaxy, robbing the black hole of its fuel source and likely explaining why the area looks so quiet today.

When stars go stagnant

Scientists are curious about how quickly star formation ceases in ancient galaxies such as this one. Luckily, MRG-M0138 is just part of a larger dataset of early-universe galaxies gathered from James Webb Space Telescope (JWST) observations; the research team also examined four other distant, gravitationally lensed galaxies with the telescope this last year, and analysis is ongoing.

"While the stars in MRG-M0138 are ancient, star formation shut down much later in the other galaxies that we've just observed with JWST," lead author Andrew Newman, a staff scientist at Carnegie Science in California, told Live Science in an email.

"They're like cinders that we can study to learn what put out the fire," Newman continued, then alluded to a direction of future research. "In particular, we're looking for signs of gas that's been blown out of the galaxy, by a black hole more active than the one in MRG-M0138."

Aside from the star-formation sequence at MRG-M0138, the researchers also determined the mass of its black hole — which is roughly six billion times that of the sun.

Making this measurement wasn't easy; because MRG-M0138's black hole is dormant and not interacting with any gas around it, it's invisible in all wavelengths of light. Weighing the cosmic monster required repurposing a technique using star motions, usually used in galaxies much closer to Earth. To track the motion of stars orbiting the black hole, the team relied on a natural magnifying glass, called gravitational lensing.

Researchers took advantage of another galaxy, between MRG-M0138 and Earth, whose gravity is so powerful that it bent the light of objects behind it, magnifying groups of stars. This lens made the image of MRG-M0138 about 30 times larger than what would usually be visible, allowing the researchers to track the stars whirling about the black hole. The team then analyzed the stars' motions to determine how quickly they moved, as well as any differences in motion between stars that were closer or further from the black hole, to figure out the black hole's mass.

"By demonstrating the feasibility of such a technique for galaxies in the early universe, we can now undertake a more complete census of how black holes develop over time, and infer their role in shaping galaxy evolution," senior author Richard Ellis, an astrophysics professor at University College London, said in a statement.

That said, other techniques will be needed to gather that census of black holes because JWST is designed to take a very detailed look at a small patch of sky. To push the research forward, the team is hoping for lensed-galaxy observations from the wide-angle Euclid space telescope — as well as the forthcoming Nancy Grace Roman Space Telescope, which is also optimized to look at large swaths of the sky.

"We want to find more galaxies like these: places where star formation shut down in the early universe, and that are magnified by a gravitational lens," Newman told Live Science. "We need sensitive infrared images of large areas of sky to find these rare objects, and fortunately that is exactly what the Euclid telescope is providing and the Roman Space Telescope, scheduled for launch later this year, will soon deliver."

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Astronomers have found the most extreme example yet of a black hole outweighing its own galaxy, and it may be hiding clues to how the supermassive black holes seen today formed in the early universe.

In a new study, astronomers directly measured the mass of a black hole sitting in a "little red dot" seen when the universe was just 700 million years old. The results suggest that the black hole is much too massive for its host galaxy ‪—‬ meaning it may have formed before the galaxy itself had a chance to develop.

Little red dots (LRDs) are a mysterious class of objects detected in the early universe. The LRD in question, Abell2744-QSO1 (or just "QSO1"), was discovered in James Webb Space Telescope (JWST) images in 2023. It was compact and strongly lensed — appearing three times in the image as its light was warped by powerful gravitational effects — and showed telltale signs of an actively feeding black hole at its center. Indirect estimates of the black hole's mass, based on the spectral properties, relied on assumptions calibrated in the local universe and have been heavily debated. Some researchers argue that little red dots are so puzzling that standard assumptions from the local universe cannot explain them, and that exotic phenomena may be at play.

In the new study, published May 27 in the journal Nature, astronomers took a more direct approach and mapped how fast gas rotates at different distances from the center to estimate the black hole's mass. The findings suggest that the methods astronomers use to study black holes in the nearby universe may work just as well for these little red dots.

"This measurement is the first of its type in a Little Red Dot, at least for now," Ignas Juodžbalis, a doctoral candidate at the Kavli Institute for Cosmology at the University of Cambridge and first author of the study, told Live Science in an email.

When the "stars" aligned

Earlier indirect estimates had placed black hole QSO1’s mass at around 40 million solar masses ‪—‬ remarkably high for such a compact, young system. The larger and more isolated the black hole is relative to its surroundings, the bigger its sphere of influence ‪—‬ the region where its gravity dominates over the stars, gas and dark matter around it. A high-mass black hole, therefore, makes it easier to detect its gravitational influence in the motions of nearby gas.

Adding to this, the galaxy cluster Abell 2744 — located between us and QSO1 — is so massive that its gravity acts as a magnifying glass. Through this effect, known as gravitational lensing, astronomers can see QSO1 brightening by a factor of six and stretching it spatially by a factor of 3.5.

Overall, these conditions were favorable to make the kind of measurement the researchers were aiming for.

The measurement technique relied on the principle that gas orbiting a black hole moves faster the closer it gets to it. By mapping how fast gas moves at different distances from the center of QSO1, the team could work backward to calculate the mass of whatever sat at the center.

The team used JWST's Near-Infrared Spectrograph to extract maps of hydrogen emission line gas, tracking which parts of QSO1 were moving toward us and which were moving away. But the object was so small and distant that the rotation signal in the inner regions fell below what JWST could directly resolve.

So they used spectroastrometry, a technique that measures tiny positional shifts in the light emitted by glowing gas across different wavelengths. This method can recover spatial information far below the telescope's nominal resolution. "This way, we were able to reconstruct the rotation curve below the instrumental resolution of JWST," Juodžbalis explained.

Not too exotic

The results were then fitted with different mass models. A point mass, where all the mass is concentrated at a single location as in a black hole, fit the data well, while a compact yet extended mass distribution, such as a tightly packed cluster of stars matched it poorly. As an independent check, co-author Cosimo Marconcini, a doctoral candidate in astronomy and physics at the University of Florence, ran the full dataset through a 3D framework he developed that models both the movement of the gas and instrumental effects of the telescope, and arrived at the same result. Juodžbalis said the independent confirmation was what gave the result its weight.

Analysis showed that the observations are best explained by a a black hole of around 50 million solar masses. The team is "reasonably confident" that this is indeed a black hole rather than other alternatives. If you were to try to explain their results with a star cluster with a solid edge, Juodžbalis said, it would be far more exotic and difficult to justify than a black hole.

Interestingly, the new measurement lined up closely with the earlier indirect estimate. Juodžbalis cautioned that a single object does not represent an entire population. However, the result suggests the standard indirect black hole mass measurements developed for the local universe may work for little red dots, too. "There may be no need to invoke anything too exotic to explain the properties of Little Red Dots," he said.

"Naked" black hole

The team placed an upper limit on the mass of the stars in the host galaxy at around 20 million solar masses. This means the black hole significantly outweighs its entire host galaxy. Astronomers call such objects "naked" black holes, and QSO1 appears to be the most massive of this kind ever found.

With its massive black hole and its near-absent host galaxy, QSO1 appears to be a massive black hole seed caught in the very first stages of growth, before its galaxy had a chance to develop around it. This finding challenges the standard picture in which black holes grow together with their galaxy over billions of years.

The team considered two exotic origin scenarios for this black hole: direct collapse black holes, which form when massive clouds of pristine gas collapse straight into a black hole without forming stars first, and primordial black holes, which would have formed in the first second after the Big Bang.

"Both scenarios are exotic, and the current data and theory are not quite able to distinguish them," Juodžbalis said.

The team plans to use upcoming ground-based observations to probe the black holes within similar objects that have been found in the local universe.

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A unique, X-ray-spewing black hole may help to confirm the enigmatic identity of "little red dots," a curious class of objects that are observed mostly in the very early universe, approximately 12 billion light-years away.

Astronomers have sought to classify little red dots (LRDs) since the James Webb Space Telescope (JWST) first spotted them shortly after it began science operations in 2022.

Over the following few years, JWST discovered hundreds more of these ancient, compact curiosities, which look like little red dots partially because their light has been redshifted — stretched into longer wavelengths — as it has traveled across billions of light-years of expanding space-time to reach us. LRDs appear to be ephemeral, emerging around 600 million years after the Big Bang and then mostly disappearing over the next billion years.

Now, in a paper published March 16 in The Astrophysical Journal Letters, astronomers have described an object that may illuminate the murky nature of LRDs.

Formally known as 3DHST-AEGIS-12014 and colloquially called the X-ray dot (XRD), this object had remained hidden in a survey conducted by NASA's Chandra X-ray Observatory more than a decade ago. Its importance was revealed only recently, after JWST observed the same cosmic field.

"It is always wonderful to see archival data aid in solving mysteries that were completely unknown when the data were first taken," Anthony Taylor, an astrophysicist at the University of Texas at Austin who was not involved in the study, told Live Science via email. "This is a prime example of legacy science programs that continue to provide scientific value both upon their initial release and far into the future."

A single black hole may solve two cosmic mysteries

The XRD discovered by Chandra resembles an LRD, save for a few differences. The biggest one is that it is a bright source of X-ray light.

Normally, LRDs do not seem to emit X-rays. This anomaly has deepened the mystery of their identity, because active black holes commonly emit X-rays from their chaotic coronas, where infalling material reaches near light speeds and intense temperatures.

"If little red dots are rapidly growing supermassive black holes, why do they not give off X-rays like other such black holes?" co-author Anna de Graaff, an astrophysicist at the Harvard & Smithsonian Center for Astrophysics, said in a statement.

As suggested in this study and in previous research, the X-rays may be blocked by thick cocoons of gas surrounding LRDs.

The XRD offers evidence of this process. As the black hole at its heart gorges on the surrounding gas, it clears holes in its cocoon. This forms sight lines into the object's interior and allows X-rays to escape, while also preserving its overall reddish appearance ‪—‬ picture a cosmic jack-o'-lantern with its eerie inner light bleeding into the dark.

"This single X-ray object may be — to use a phrase — what lets us connect all of the dots," lead author Raphael Hviding, an astronomer at the Max Planck Institute for Astronomy in Germany, said in the statement.

Unveiling an early-universe enigma

Overall, the XRD may help strengthen the idea that LRDs are young black holes in the midst of a transitional phase, during which they're enveloped in a dense cloud of gas. This gaseous shroud is similar in composition to some stellar atmospheres, earning LRDs an awe-inspiring appellation: "black hole stars."

Accordingly, if LRDs represent a phase of rapid gas accretion by young black holes, this period of quick consumption may help to explain how early supermassive black holes (SMBHs) grew so fat, so fast, accumulating many millions or billions of solar masses when the universe was only about 10% of its current age.

It is essential to study the evolution of these objects in more recent times. "LRD-like objects have actually been found in the modern universe but it is clear that LRD analogues are exceedingly rare," Hviding told Live Science via email. "Why? The short answer is that we don't know." One possibility is that giant gas reservoirs grow thinner as the universe evolves, he said.

Next-generation observatories like the Nancy Grace Roman Space Telescope will scan the sky for the rare, modern LRDs in the evolved universe. "They cannot go nearly as deep or as detailed as Webb," Hviding added, "but because they survey wide areas of the sky, finding rare analogues becomes viable."

In the meantime, the XRD warrants further observations. Maybe it isn't an elderly LRD, after all, but a more common SMBH veiled in an exotic dust never seen before. Either way, astronomers appear to have made a distinctive discovery that may elucidate a chain of cosmic mysteries in the evolution of the universe.

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Astronomers may have discovered an extreme pair of light-spewing black holes that are spiraling toward an enormous collision — the effects of which could be felt in the next century.

Using decades of radio telescope observations, the astronomers studied an ultrabright object that was previously thought to be a blazar — a glowing core of a galaxy usually powered by a black hole — some 500 million light-years from our solar system. The observations revealed a hidden jet of energy that suggests the intensely bright object is actually two black holes on the verge of colliding, perhaps less than 100 years from now.

"We expect one (merged) black hole to remain," study co-author Silke Britzen, an astronomer at the Max-Planck Institute for Radio Astronomy, told BBC Science Focus. "I am really curious to observe how this 'dance' will continue."

The findings were published March 27 in the journal Monthly Notices of the Royal Astronomical Society.

Finding two black holes

Blazars are some of the most luminous objects in the universe. They're classified as active galactic nuclei — actively feeding objects at the centers of galaxies, usually powered by supermassive black holes — and typically shoot jets of high-energy radiation toward Earth. Usually, a central black hole is the source for this jet, but in the case of the blazar in the galaxy Markarian 501, something didn't quite add up.

For years, astronomers had observed different orientations of the jet using radio telescope data, making it difficult to determine if its core really did harbor a supermassive black hole. To answer this question, the researchers analyzed over 83 datasets from the Very Long Baseline Array, an international network of 10 radio telescopes.

The results revealed that, instead of one large jet, there was also a second jet looping counterclockwise around the blazar's center. The team believes each of these jets is powered by a supermassive black hole, each weighing between 100 million and a billion times the sun's mass.

"Realising that [there] was a second jet was awesome," Britzen told BBC Science Focus. "For me it was like: that's how it works? I was so amazed and overwhelmed — and wanted to tell everybody what we just found."

In June 2022, the two black holes lined up perfectly so that the primary black hole's gravity bent the light emitted by the second jet into a near-perfect circle known as an Einstein ring. Thanks to a phenomenon called gravitational lensing — a sort of natural magnifying glass created by intense gravitational forces — this finding adds further evidence to the idea that the blazar is powered by a pair of supermassive black holes.

"Since these jets are directed towards us, an Einstein ring supports the scenario," Britzen said.

The two black holes are thought to circle each other clockwise about once every 121 days and are separated by only 250 to 540 times the distance between Earth and the sun — relatively close in the world of astronomy. Gradually, this distance will close until the two objects ultimately merge.

The researchers think that when the doomed black holes do inevitably collide, they will release gravitational waves — ripples in the fabric of space-time unleashed by the most intense events in the universe — that could be more powerful than those from previously studied black hole mergers. If that's the case, gravitational wave detectors on Earth will pick up the signal, offering new clues about the properties of the original black hole pair.

How much do you know about black holes? Try our black hole quiz!

More than 60 years after it was first spotted, Cygnus X-1 — the first confirmed black hole — is still full of surprises. Researchers have finally measured the energy output of this behemoth's "dancing jets," and the results could help answer wider questions about the extreme behavior of black holes, experts say.

Cygnus X-1 is a stellar-mass black hole that is around 21 times more massive than the sun and located approximately 7,000 light-years from Earth, in the constellation Cygnus. It is locked in a binary orbit with an equally massive blue supergiant star dubbed HDE 226868, which it circles every 5.6 days at a distance of 0.2 astronomical unit (one-fifth the Earth-sun distance). The black hole is constantly ripping away its partner's outer layers into a superhot ring of swirling matter called an accretion disk, which shines brightly in X-ray light.

Astronomers first spotted the ionizing glow of Cygnus X-1 in 1964, when scientists were still unsure whether black holes really existed. Since it was officially confirmed in 1971, Cygnus X-1 has been studied extensively and, until recently, was considered the most massive and fastest-spinning stellar-mass black hole ever seen. Although Cygnus X-1 does not emit any visible light, it is possible to see its companion star HDE 226868 with a decent telescope, making this one of the few black hole systems you can also observe for yourself.

Like most other black holes, Cygnus X-1 shoots out two massive beams of energy. These jets, made of plasma from the accretion disk, get fired outward by the black hole's immensely powerful and rapidly spinning magnetic field. However, despite detecting dozens of similar jets and even photographing them, researchers have historically struggled to properly measure the energetic outlaws.

But in the new study, published April 16 in the journal Nature Astronomy, researchers have found a way to measure the jets of Cygnus X-1 by tracking how they wobble, or "dance," due to their close proximity to HDE 226868.

The team found that the jets shine with the equivalent energy of around 10,000 suns and that they're shooting outward at around 335 million mph (540 million km/h) — about half the speed of light.

"Dancing jets"

All active stars, including HDE 226868, emit stellar winds made up of charged particles accelerated by powerful magnetic fields (similar to black hole energy jets). These invisible gusts push against the atmospheres of planets and eventually collide with the interstellar medium.

In the case of Cygnus X-1, its energy jets are constantly buffeted by strong gusts of radiation from HDE 226868, causing the jets to bend away from the blue supergiant. Because the two objects circle a shared center of mass, the jets appear to bend back and forth, or wobble, from our point of view.

Study first author Steve Prabu, a radio astronomer at the University of Oxford, described this phenomenon as "dancing jets" due to their constant swaying motion, according to a statement emailed to Live Science.

Historically, it has been tricky to take accurate readings of these dancing jets, due to their constant movement. But researchers combined images captured by radio telescopes across the globe to build a more accurate picture of the jets' shape, thus achieving what was previously impossible.

Filling in the gaps

Researchers are particularly pleased by the new findings because they can help fill in gaps in our current black hole knowledge.

"A key finding from this research is that about 10 per cent of the energy released as matter falls in towards the black hole is carried away by the jets," Prabu said in the statement. "This is what scientists usually assume in large-scale simulated models of the universe, but it has been hard to confirm by observation until now."

While this is just one set of jets, our current understanding of black holes — based on Albert Einstein's 1915 theory of general relativity — suggests that all black hole jets, whether they belong to stellar-mass or supermassive entities, should emit a similar outflow.

"Because our theories suggest that the physics around black holes is very similar, we can now use this measurement to anchor our understanding of [other] jets, whether they are from black holes 10 or 10 million times the mass of the sun," study co-author James Miller-Jones, a radio astronomer and black hole accretion expert at Curtin University in Australia, said in the statement.

A better understanding of black hole jets will also help scientists figure out how galaxies like the Milky Way have evolved over time, based on how these monstrous outflows shape their surroundings.

"Black hole jets provide an important source of feedback to the surrounding environment and are critical to understanding the evolution of galaxies," Miller-Jones added.

A new theoretical study suggests that black holes may never fully evaporate, which contradicts an infamous Stephen Hawking theory that seems to violate fundamental laws of quantum mechanics. Instead, black holes could leave behind tiny, stable remnants that store all the information they once consumed, the study suggests.

But there's a twist — literally. For the theory to work, the universe must have three extra hidden dimensions that humans cannot perceive, making space-time seven-dimensional. As these hidden dimensions fold and twist, they create a repulsive force that prevents black holes from evaporating entirely.

The work, while hard to test directly, links black holes to the geometry of extra dimensions, offering a fresh approach to one of the deepest puzzles in physics.

A paradox that challenges the foundations of physics

Black holes are often thought of as cosmic traps from which nothing escapes. Yet, since the 1970s, physicists have known that these cosmic behemoths are not entirely black. Famed theoretical physicist Stephen Hawking proposed that black holes emit radiation and slowly evaporate over time, which leads to a troubling contradiction known as the information loss paradox.

"Imagine you throw a book into a fire," study co-author Richard Pinčák, a senior researcher at the Slovak Academy of Sciences' Institute of Experimental Physics, told Live Science via email. "The book is destroyed, but in principle you could reconstruct every word from the smoke, ash, and heat — the information is scrambled, not lost."

But when a black hole evaporates completely, the information about everything that fell into it appears to vanish, violating a core principle of quantum mechanics.

For decades, physicists have struggled to resolve this paradox. Now, the new study, published March 19 in the journal General Relativity and Gravitation, suggests the answer may lie in the hidden structure of space-time itself.

Extra dimensions and the hidden structure of space-time

The new research explores a universe with more dimensions than the familiar four. In this framework, the cosmos contains seven dimensions, three of which are compact and invisible at everyday scales.

"We experience three dimensions of space and one of time — four dimensions in total," Pinčák said. "Our model proposes that the universe actually has seven dimensions: the four we know, plus three tiny extra dimensions curled up so tightly that we cannot directly perceive them."

These extra dimensions are arranged in a highly symmetrical structure known as a G₂ geometry. This mathematical framework, often explored in advanced theories such as a version of string theory known as M-theory, determines how the hidden dimensions are "folded."

"Think of it like origami," Pinčák said. "The way you fold the paper determines what the final shape can do."

In the new model, this geometric structure produces a physical effect called torsion, which can be thought of as a twisting of space-time. This torsion field turns out to play a crucial role in black hole physics.

Torsion and the birth of stable black hole remnants

The study shows that torsion generates a repulsive force that becomes important at extremely small scales, near the end of a black hole's life. As the black hole shrinks through Hawking radiation, this force eventually counteracts further collapse.

"This repulsive force acts as a brake, halting the evaporation before the black hole vanishes completely," Pinčák said.

Instead of disappearing, the black hole stabilizes into a tiny remnant. According to the model, this leftover object has a mass of about 9 × 10⁻⁴¹ kilograms ‪—‬ some 10 billion times smaller than an electron.

Crucially, this remnant can store the information that fell into the black hole, avoiding any violation of quantum mechanics. The information is encoded in subtle oscillations known as quasinormal modes, which act as carriers of the lost data.

The model also reveals an unexpected connection to particle physics: The existence of three hidden dimensions, together with the presence of torsion, produces the pattern of particle interactions responsible for the Higgs mechanism, the phenomenon that gives mass to elementary particles like electrons and quarks.

"The same torsion field… generates a potential energy landscape that is identical in form to the one responsible for giving mass to the W and Z bosons — the carriers of the weak nuclear force," Pinčák said.

This link ties the behavior of black holes to the electroweak scale, a well-known energy scale in particle physics.

Where the new theory reaches its limits

Despite its appeal, the model faces important challenges. The standard description of black hole evaporation relies on a semiclassical approximation, which is expected to break down at extremely small scales near the Planck mass — approximately 10^-5 grams. This is the mass scale at which quantum gravitational effects become strong and impossible to ignore.

"As the black hole shrinks toward the Planck scale, all existing models — ours included — must eventually confront the transition into the deep quantum-gravity regime," Pinčák noted.

In this regime, a full theory of quantum gravity is required, but such a theory remains incomplete. The new work does not claim to solve this problem entirely. Instead, it provides a concrete mechanism for how new physics could emerge at the final stage of evaporation.

"What distinguishes our approach is that we do not claim semiclassical evaporation operates all the way down to the remnant mass," Pinčák said. "At that point, a new physical effect … takes over and stabilises the configuration."

Testing the theory directly will be extremely difficult; the relevant energy scales are far beyond the reach of current particle accelerators. However, the model makes clear predictions that could, in principle, be tested.

For example, it predicts that hypothetical Kaluza-Klein particles associated with extra dimensions should have masses of around 10¹⁶ gigaelectronvolts ‪—‬ about 14 orders of magnitude heavier than the top quark, the most massive known elementary particle. Detecting lighter versions of these particles with current or future accelerators would rule out the model.

Another possibility involves observing the final stages of black hole evaporation, particularly for primordial black holes. Future gamma-ray telescopes or gravitational wave detectors could provide indirect evidence for stable remnants.

"The important point is that the predictions are concrete — the model can be wrong, which is what makes it scientific," Pinčák said.

Looking ahead, the researchers aim to connect their framework more directly to fundamental theories such as M-theory and to better understand how information is stored in the remnants. If confirmed, the idea that black holes leave behind tiny, information-rich remnants could reshape our understanding of gravity, quantum mechanics and the fundamental structure of the universe.

How much do you know about black holes? Test your cosmic knowledge with our black hole quiz!

For years, astronomers have been puzzled by why the biggest black holes in the universe have been growing much more slowly over the past 10 billion years. Now, a new study offers a potential solution to this astrophysical enigma: They're starved for gas.

Supermassive black holes (SMBHs) have immense gravitational appetites that allowed them to grow to many millions or billions of times the mass of the sun at surprisingly rapid rates in the first few billion years after the Big Bang. However, SMBHs have been growing ever more slowly since the period known as "cosmic noon," when the universe was less than a quarter of its current age.

Scientists have long wondered why this could be: Are there just fewer feeding black holes out there now, or is some external force stunting their growth?

The actual reason may be that there's simply less material for them to munch on, scientists suggested in a paper published Dec. 17 in The Astrophysical Journal.

"We knew black holes were growing more slowly, but not why — and it turned out to be that individual black holes are consuming material much less rapidly, rather than there simply being fewer growing black holes or smaller ones," study co-author Fan Zou, an astronomer at the University of Michigan, told Live Science via email.

Beefy black holes on a diet

Studying the growth of black holes is crucial for understanding galactic evolution and star birth, because SMBHs and their host galaxies evolve in a coordinated manner. SMBH sizes also correlate with the total mass of stars and their chaotic movements in a galaxy's bulge — the football-shaped central region where stars are densely packed.

To measure how black hole growth has changed throughout cosmic time, the researchers utilized data from nine extragalactic surveys collected in a "wedding cake" design. These tiered layers include shallow surveys of large, relatively nearby regions of the sky, as well as extremely deep "pencil-beam" looks at smaller fields, gathered from the world's premier X-ray-based space telescopes, including NASA's Chandra X-ray Observatory, the European Space Agency's XMM-Newton and the German-Russian eROSITA.

"X-ray light is arguably the best tracer of black hole growth," lead author Zhibo Yu, an astronomer at Penn State, told Live Science via email. "It is ubiquitously produced by growing supermassive black holes and has high contrast compared to the background star light. It also has high-penetrating power — that's why it's commonly used in medical imaging — so that it is less affected by the obscuring gas and dust in the galaxy."

Altogether, the researchers analyzed multiwavelength observations of 1.3 million galaxies and 8,000 actively feeding, X-ray-spewing SMBHs to determine why the black holes' growth rate has plummeted.

Have black holes had their heyday?

The research tested three main ideas. For example, are the black holes in the modern universe gobbling less matter? Alternatively, are they simply smaller and, therefore, less gravitationally gluttonous than their ancient predecessors? Or are there fewer actively growing black holes overall?

The researchers concluded that the black holes' consumption has slackened as the amount of cold gas for them to gobble has decreased since cosmic noon, approximately 10 billion years ago. "What surprised me most was that we could actually isolate the main reason, and there is indeed a dominating reason instead of a messy mix," Zou explained.

This decrease in growth rates appears to be significant. "Our best estimate is that the decrease is a factor of 22," study co-author Neil Brandt, an astrophysicist at Penn State, told Live Science via email. Although this study did not address the bafflingly fast black hole growth in the very early universe, "it does the best job so far of [addressing] the final 75% of cosmic time — a large majority!"

Future work may focus on additional datasets, such as wide-field X-ray surveys from Chandra and XMM-Newton, as well as multiwavelength data from other observatories. As a result, astronomers will be able to uncover larger SMBH populations, including even older examples and those that are obscured by dense dust and gas.

Finally, the research further confirms that the eras of rampant SMBHs are behind us. "We do not expect many SMBHs to emerge and significantly grow in the future," Zou said. "Actually, we found in 2024 that the number of SMBHs was almost settled by 7 billion years ago — and will likely continue to be so in the future."

How much do you know about black holes? Test your knowledge with our black hole quiz!

The universe-shaking collision of a black hole and a neutron star just led astronomers to a strange type of orbital interaction never seen before, and it's forcing them to rethink their theories.

Before the two extremely dense objects crashed and combined, they first swooped around each other in an eccentric, oval shape resembling the swirls of a Spirograph, scientists reported March 11 in The Astrophysical Journal Letters.

The new discovery challenges the prevailing assumption about how black holes and neutron star systems form, and whether they must fall into perfectly circular orbits before they die, according to the study authors.

"The fact that this system is still eccentric at the very end of its life is essentially a smoking‑gun signal that at least some neutron star-black hole binaries must form differently [than theory predicts]," study co-author Patricia Schmidt, an associate professor of physics and astronomy at the University of Birmingham in the U.K., told Live Science in an email. This observation "forces us to rethink where, and under what conditions, these systems arise."

Einstein's ripples

In January 2020, scientists detected the first compelling evidence of a black hole swallowing a neutron star — the ultradense, collapsed core of a once-massive star — resulting in the creation of a new black hole with roughly 13 times the mass of Earth's sun.

Although the event occurred roughly a billion light-years from Earth, the researchers measured the properties of the two objects using a pair of gravitational waves. These ripples in space-time are released by extreme cosmic collisions and were first predicted by Einstein's relativity. Researchers detected the two waves, which arrived 10 days apart, using the Laser Interferometer Gravitational-Wave Observatory (LIGO) in the United States, comprising two gravitational wave detectors separated by 1,900 miles (3,000 kilometers). The first wave, labeled GW200105, is the focus of the new study.

Using a new model developed by the University of Birmingham's Institute of Gravitational Wave Astronomy, as well as complementary data from the Virgo interferometer gravitational wave detector in Italy, the team refined their measurements of the space-time ripple and found that some initial assumptions were wrong. For example, the earlier studies of GW200105 underestimated the black hole's mass while overestimating the neutron star's mass. Those values have now been corrected.

More importantly, prior studies also assumed a perfectly circular orbit for the black-hole-neutron-star system leading up to the collision, as is often the case in pairs like these. The new research rules out that possibility with 99% certainty — also throwing the system's origins into question.

The circle is broken

Black holes and neutron stars both form when once-mighty stars exhaust their fuel and collapse into dense remnants. Under certain circumstances, two remnants can fall into a shared, binary orbit that slowly pulls the objects toward a catastrophic collision.

"Canonically, neutron star-black hole binaries are thought to form from pairs of isolated massive stars that evolve together until one becomes a black hole and the other a neutron star," Schmidt told Live Science. "However, this formation pathway predicts that by the time the objects are close enough for LIGO and Virgo to detect them, their orbit should be almost perfectly circular. An eccentric orbit at such small separations is therefore very difficult to reconcile with this standard scenario."

To paint a clearer picture of the doomed system's orbit, the new analysis looked at two underexplored properties: eccentricity (how oval the system's orbit was, like the elliptical orbit of the moon around Earth) and precession (how the rotational axis of an object changes or wobbles over time). This was the first time scientists analyzed both properties at once in a merger of a black hole and a neutron-star, according to the researchers.

The team found that the system's orbit was highly eccentric (oval-shaped), but there was no compelling evidence of precession. According to the team, this means the system's oddly egg-shaped orbit had nothing to do with changes in its rotational axis. Rather, it was most likely imprinted on the system long before its death — likely due to the gravitational pull of other objects in its environment.

"The orbit gives the game away," study co-author Geraint Pratten, a Royal Society University research fellow at the University of Birmingham, said in a statement. "Its elliptical shape just before merger shows this system did not evolve quietly in isolation but was almost certainly shaped by gravitational interactions with other stars, or perhaps a third companion."

A "new window" into the universe

This evidence of an oval-shaped orbit is a first among black-hole-neutron-star systems.

While the exact mechanism behind it remains a mystery, its mere existence proves there is no one-size-fits-all explanation for how these systems form and points to a freshly opened gap in our understanding of these extreme objects.

Narrowing that gap will require new models based on more unusual gravitational wave signals from across the universe. Finding those faint signals may require new technology, such as the forthcoming space-based Laser Interferometer Space Antenna (LISA) detector, currently under construction.

"Future gravitational‑wave detectors, both on the ground and in space, will open an entirely new window on the universe," Schmidt concluded. "They will be far more sensitive than current instruments, allowing us to detect fainter and more distant sources, and even completely new types of gravitational‑wave signals that are beyond our reach today."

Editor's note: This article was updated March 11 at 10:15 a.m. to link to the published study. It was further updated on March 23, to replace an image of the Virgo detector that was erroneously described as the LIGO detector. The distance between the two LIGO facilities has also been clarified.

Black hole quiz: How supermassive is your knowledge of the universe?

Like physics, math has its own set of "fundamental particles" — the prime numbers, which can't be broken down into smaller natural numbers. They can only be divided by themselves and 1.

And in a new development, it turns out these mathematical "particles" are offering new ways to tackle some of physics' deepest mysteries. Over the past year, researchers have found that formulas based on the prime numbers can describe features of black holes. Number theorists have spent hundreds of years deriving theorems and conjectures based on the primes. These new connections suggest that the mathematical truths that govern prime numbers may also govern some fundamental laws of the universe. So can physics be expressed in terms of primes?

Black holes are the sites of the universe's most crushing gravitational force. At their centers lie single points called singularities, where classical physics predicts that gravity must be infinite, causing our understanding of space and time to break down. But in the 1960s, physicists found that, immediately surrounding the singularity, a type of chaos emerges — and it looks remarkably similar to a kind of chaos recently found in the primes.

Physicists hope to make use of the connection. "I'd say many high-energy physicists don't actually know much about that side of number theory," says Eric Perlmutter of the Institute of Theoretical Physics, Saclay.

Number theory's foundational conjecture on primes is the 1859 Riemann hypothesis. In a hand-written paper, German mathematician Bernhard Riemann provided a formula with two main terms. The first offered a startlingly close estimate for how many prime numbers exist that are smaller than a given number. The second term is the zeta function, whose zeros (the places where the function is equal to zero) tune up the original estimate. The mysterious way in which the zeta zeros always improve the estimate is the subject of the Riemann hypothesis. The hypothesis is so crucial to number theory that anyone who can prove it will earn a $1-million Clay Mathematics Institute prize.

In the late 1980s physicists started to wonder if there was a physical system whose energy levels might be based on the prime numbers. Physicist Bernard Julia of the École Normale Supérieure in France was challenged by a colleague to find a physics analogue described by the zeta function. His solution was to propose a hypothetical kind of particle with energy levels given by the logarithms of prime numbers. Julia called these particles "primons" and a group of them a "primon gas." The partition function — a census of a system’s possible states — of this gas is exactly the Riemann zeta function.

At the time, Julia's concept was a thought experiment — most scientists doubted that primons actually existed. But deep inside black holes, a mathematical link awaited discovery. A little more than two decades later, physicists Yan Fyodorov of King's College London, Ghaith Hiary of Ohio State University and Jon Keating of the University of Oxford saw hints that fractal chaos emerges from the fluctuations of the zeta function's zeros, an idea that was conclusively proven in 2025.

Einstein's general theory of relativity shows that the same chaos also arises near a singularity.

In a February 2025 preprint, University of Cambridge physicist Sean Hartnoll and graduate student Ming Yang brought Julia's work into the real world. Inside the chaos close to a singularity, they found that a "conformal" symmetry emerges. Hartnoll likens conformal symmetry to Dutch artist M. C. Escher's famous drawings of bats — the same structure repeats on different scales. This scaling symmetry, together with a bit of math, revealed a quantum system near the singularity whose spectrum organizes into prime numbers — a conformal primon gas cloud.

Five months later, they uploaded a preprint with a new twist. The team, which now included University of Cambridge University physicist Marine De Clerck, expanded their analysis to a five-dimensional universe instead of the usual four. They found that the extra dimension forced a new feature: keeping track of the singularity's dynamics now required a "complex" prime number, known as a Gaussian prime, that includes an imaginary component (a number multiplied by the square root of –1). Gaussian primes can't be divided any further by other complex numbers. The authors dubbed this system a "complex primon gas."

"We don't know yet whether the appearance of prime number randomness close to a singularity has a deeper meaning," Hartnoll says. "However, to my mind, it is very intriguing that the connection extends to higher dimensional theories of gravity," including some candidates for a fully quantum mechanical theory of gravity.

And in a late 2025 preprint, Perlmutter proposed a new framework involving the zeta zeros. He relaxed the restrictions on the zeta function so it could rely not just on integers but on all real numbers, including irrationals. Doing so opened up even more powerful zeta function techniques to understand quantum gravity. Physicist Jon Keating of the University of Oxford, who was not involved in the new research, says that broader perspectives such as this can reveal new ways to tackle long-standing problems. "It's only when you step back and look at the whole mountain that you think, 'Ah, there's a much better way to get up over there,'" he says.

Perlmutter cautiously hopes the flurry of prime physics will hasten new discoveries, but the approach is one of many fighting for acceptance. "The kinds of things we're trying to understand, black holes in quantum gravity, are surely governed by some beautiful structures," he says. "And number theory seems to be a natural language."

This article was first published at Scientific American. © ScientificAmerican.com. All rights reserved. Follow on TikTok and Instagram, X and Facebook.

Albert Einstein quiz: What do you know about the life of the famous theoretical physicist?

Physicists may have a brand-new way to measure the expansion rate of the universe — one of the biggest outstanding mysteries in cosmology — using space-time ripples predicted by Einstein.

A new study suggests that the faint gravitational wave background produced by numerous merging black holes across the universe can be used to independently measure how fast space is expanding. Even without detecting this background "hum" directly, the researchers show that it already places limits on the Hubble constant — a key quantity at the heart of one of modern cosmology's biggest puzzles.

If confirmed, the technique could settle the debate about whether we need to come up with new physics to explain the nature of the universe.

An independent test of the Hubble constant

The expansion rate of the universe, encoded in the Hubble constant, has become the focus of intense debate in recent years. Measurements based on the early universe, such as those inferred from the leftover radiation from the Big Bang (known as the cosmic microwave background), disagree with measurements derived from more nearby objects, like flickering supernovas and galaxies. This discrepancy, known as the Hubble tension, has now reached high statistical significance.

"The Hubble tension is one of the most important open problems in cosmology," Chiara Mingarelli, an assistant professor of physics at Yale University who was not involved in the new study, told Live Science via email. "Early-Universe and late-Universe measurements of the expansion rate disagree at over 5 sigma [the "gold standard" of statistical significance in physics], and we don't know why. Either there's an unidentified systematic error or new physics. Any genuinely independent measurement of the expansion rate is extremely valuable."

The new research, accepted for publication in the journal Physical Review Letters and available as a preprint, proposes such an independent method based almost entirely on gravitational waves — subtle ripples in the fabric of space-time predicted by Einstein's theory of general relativity.

"This result is very significant," study co-author Nicolás Yunes, a professor of astrophysics at the University of Illinois Urbana-Champaign, said in a statement. "Our method is an innovative way to enhance the accuracy of Hubble constant inferences using gravitational waves."

Listening to the background hum of black holes

Since 2015, detectors such as the Laser Interferometer Gravitational-Wave Observatory (LIGO), the Virgo interferometer, and the Kamioka Gravitational Wave Detector (KAGRA) have observed dozens of individual black hole mergers through gravitational waves. Each merger provides information about the masses of the black holes involved and their distances from Earth.

"Because we are observing individual black hole collisions, we can determine the rates of those collisions happening across the universe," lead study author Bryce Cousins, a graduate student at the University of Illinois Urbana-Champaign, said in the statement. "Based on those rates, we expect there to be a lot more events that we can't observe, which is called the gravitational-wave background." This gravitational wave background, sometimes described as a stochastic (or random) signal, is the faint, collective effect of numerous distant mergers. Its overall strength depends on how quickly the universe is expanding. A slower expansion implies larger cosmic volumes and, therefore, more mergers contributing to the background.

"It's a clever idea," Mingarelli said. "The gravitational-wave background — the collective hum of distant black hole mergers too faint to detect individually — depends on the expansion rate. A slower expansion means larger volumes, more mergers, and a louder background. So even the non-detection of this background disfavors low values of the Hubble constant."

Using current data from gravitational wave detectors, the team showed that the absence of a detected background already rules out some lower values of the Hubble constant. While the present constraints are broad, the method establishes a new framework for cosmological inference.

A new tool for cosmology

The approach builds on the concept of "standard sirens," in which individual gravitational wave events act as distance markers. But instead of relying on single bright events, the new method exploits the entire unresolved population of colliding black holes.

"It's not every day that you come up with an entirely new tool for cosmology," study co-author Daniel Holz, a professor of physics and astronomy at the University of Chicago, said in the statement. "We show that by using the background gravitational-wave hum from merging black holes in distant galaxies, we can learn about the age and composition of the universe.

"This is an exciting and completely new direction, and we look forward to applying our methods to future datasets to help constrain the Hubble constant, as well as other key cosmological quantities," Holz added.

While the new method shows promise, Mingarelli also emphasized the current limitations. "The main strength is that this is an almost entirely gravitational-wave-based measurement — independent of the electromagnetic distance ladder and the cosmic microwave background," Mingarelli said. "The limitation is that uncertainties are still large, and the result depends on the assumed black hole population model. But the authors are upfront about this and show their choices are conservative."

Looking ahead, detector upgrades are expected to significantly improve sensitivity to the gravitational wave background.

"With planned detector upgrades, the background should be detected within a few years, turning this from a lower bound into a real measurement," Mingarelli said.

If successful, this stochastic siren method could become a powerful new tool for probing the expansion history of the universe and for investigating whether the Hubble tension signals new physics or hidden systematic errors in existing measurements.

Black hole quiz: How supermassive is your knowledge of the universe?

In 1974, a brilliant 32-year-old physicist published a not-quite-two-page paper in the journal Nature — and blew up one of our fundamental assumptions about black holes.

The author was Stephen Hawking, and the paper, "Black hole explosions?," would become his most lasting legacy.

According to Einstein's theory of relativity, black holes are so massive that nothing, not even light, can escape their clutches. By that logic, black holes should grow only as the universe ages, devouring nearby matter or merging with other black holes to eventually reach supermassive scales.

But for a few years prior to his seminal paper, Hawking had been investigating how quantum mechanics — the strange laws that govern subatomic particles — would impact black hole growth and evolution. Building on the work of theoretical physicist Jacob Bekenstein, he combined general relativity, the laws of thermodynamics and relatively simple quantum physics to deduce that black holes radiate minuscule amounts of heat.

In his popular 1988 book "A Brief History of Time," Hawking claimed that was because pairs of "virtual" particles pop in and out of existence throughout the universe, annihilating on contact.Occasionally, however, one member of the pair would emerge just outside a black hole's event horizon, while the other would be just inside that boundary. One would fall in, while the other would escape, carrying a tiny bit of heat with it. Over time, this loss of heat, or radiation, would shrink the black hole, leading its surface gravity to increase. That, in turn, would make the black hole accelerate the radiation, leading to the black hole's eventual evaporation, possibly via explosion.

(In fact, later research showed that particle-antiparticle explanation is grossly simplified, and Hawking radiation actually appears as a result of the acceleration of an observer close to a black hole's event horizon.)

For black holes with the mass of the sun or bigger, evaporation by what's now known as "Hawking radiation" would take longer than the age of the universe, the study concluded. But Hawking also wondered whether tiny primordial black holes were formed from "quantum fluctuations" at the dawn of time. These tiny black holes, smaller than about 1 trillion kilograms, would have long since blown up, he concluded.

"This is a fairly small explosion by astronomical standards but it is equivalent to about 1 million 1 Mton hydrogen bombs," Hawking dryly noted in his paper.

Hawking radiation soon became firmly entrenched in physics theory. But it also revealed a huge paradox in black hole physics: Evaporation meant that "information" that fell into a black hole was lost forever. That, in turn, would violate a central tenet of quantum mechanics: that information cannot be created or destroyed. For the next four decades, until his death in 2018, Hawking would chip away at the black hole information paradox.

In a 2015 public lecture in Sweden, Hawking reiterated his proposal that information can indeed escape a black hole, possibly via a wormhole.

"Black holes ain't as black as they are painted. They are not the eternal prisons they were once thought," Hawking said. "Things can get out of a black hole both on the outside and possibly come out in another universe."

After his death, some of his collaborators published a series of papers that seemed to resolve the paradox; information is not lost once it enters a black hole, they posited, but regurgitated.

And in 2024, physicists proposed a way to find it: The information gobbled up by a black hole would leave traces in subtle ripples in the space-time surrounding these cosmic monsters. These ripples would reveal themselves in gravitational waves we're already detecting using massive observatories.

Scientists have yet to find direct evidence for black hole explosions or primordial black holes. But the James Webb Space Telescope recently detected an ancient galaxy that could be explained by primordial black holes.

A surprisingly ravenous black hole from the dawn of the universe is breaking two big rules: It's not only exceeding the "speed limit" of black hole growth but also generating extreme X-ray and radio wave emissions — two features that are not predicted to coexist.

The object — a quasar known as ID830 — is an extremely bright and active supermassive black hole (SMBH) that is shooting immense jets of radiation from its poles. It is also emitting intense X-ray emissions, generated by infalling material that swirls around its dark maw at nearly the speed of light.

ID830 is exceptionally massive. It already weighed 440 million solar masses around 12 billion years ago, when the universe was approximately 15% of its current age. That makes it over 100 times more massive than Sagittarius A*, the SMBH at the heart of our Milky Way galaxy.

How is this rule-breaking behavior even possible? In a paper published Jan. 21 in The Astrophysical Journal, an international team of researchers observed ID830 in multiple wavelengths to find an answer.

Even black holes have limits

Black holes are the universe's most voracious eaters, but even monsters have a feeding limit. As they attract gas and dust, this material accumulates in a swirling accretion disk. Gravity pulls the material from the disk into the black hole, but the infalling material generates radiation pressure that pushes outward and prevents more stuff from falling in. As a result, black holes are muzzled by a self-regulating process called the Eddington limit.

Yet black holes can temporarily bypass this limit and undergo rapid growth spurts at a super-Eddington limit. Researchers propose multiple mechanisms for this cosmic gluttony. For example, "it should be perfectly possible for a black hole to consume matter faster than the Eddington limit for a short period of time before radiation pressure builds up to limit the accretion rate," Anthony Taylor, an astronomer at the University of Texas at Austin who was not involved in the study, told Live Science via email.

Alternatively, a black hole can consume matter from a disk around its equator while outward radiation pressure expels material from its poles. "In this situation, the radiation pressure would not directly oppose the inflow of matter, thus allowing the Eddington limit to be exceeded," Taylor added. "There are a variety of geometries where this could work!"

Super-Eddington mechanics may help reconcile SMBH growth models with an expanding catalog of early-universe observations. With its exceptional infrared sensitivity, the James Webb Space Telescope has revealed that SMBHs grew surprisingly fast and surprisingly early, defying all expectations.

So, how did SMBHs get so fat, so fast? Some scientists suggest that Population III stars, the first and largest stars in cosmic history, collapsed to produce black hole "seeds" of 1,000 or more solar masses.

But even these hefty seeds would need to feed at the Eddington limit for more than 650 million years to reach some of their observed sizes. This feat may seem infeasible for several reasons, including the prodigious amounts of gas required to sustain such prolonged gorging.

Supercharging black hole growth

The researchers calculated ID830's growth rate by measuring its brightness in ultraviolet (UV) and X-ray wavelengths. Its X-ray brightness suggests that ID830 is accreting mass at about 13 times the Eddington limit, due to a sudden burst of inflowing gas that may have occurred as ID830 shredded and engulfed a celestial body that wandered too close.

"For a SMBH as massive as ID830, this would require not a normal (main-sequence) star, but a more massive giant star or a huge gas cloud," study co-author Sakiko Obuchi, an observational astronomer at Waseda University in Tokyo, told Live Science via email. Such super-Eddington phases may be incredibly brief, as "this transitional phase is expected to last for roughly 300 years," Obuchi added.

ID830 also simultaneously displays radio and X-ray emissions. These two features are not expected to coexist, especially because super-Eddington accretion is thought to suppress such emissions. "This unexpected combination hints at physical mechanisms not yet fully captured by current models of extreme accretion and jet launching," the researchers said in a statement.

So while ID830 is launching massive radio jets, its X-ray emissions appear to originate from a structure called a corona, produced as intense magnetic fields from the accretion disk create a thin but turbulent billion-degree cloud of turbocharged particles. These particles orbit the black hole at nearly the speed of light, in what NASA calls "one of the most extreme physical environments in the universe."

A framework for early galaxy evolution

Altogether, ID830's rule-breaking behaviors suggest that it is in a rare transitional phase of excessive consumption — and excretion. This incredible feeding burst has energized both its jets and its corona, making ID830 shine brightly across multiple wavelengths as it spews out excess radiation.

Additionally, based on UV-brightness analysis, quasars like ID830 may be unexpectedly common, the researchers said. Models predict that only around 10% of quasars have spectacular radio jets, but these energetic objects could be significantly more abundant in the early universe than previously suggested.

Most importantly, ID830 also shows how SMBHs can regulate galaxy growth in the early universe. As a black hole gobbles matter at the super-Eddington limit, the energy from its resultant emissions can heat and disperse matter throughout the interstellar medium — the gas between stars — to suppress star formation. As a result, ancient SMBHs like ID830 may have grown massive at the expense of their host galaxies.

Theory shows that stars can collapse directly into black holes without first exploding as supernovae. In fact, this should be a relatively common occurrence. But despite that, astronomers have found scant observational evidence to support it.

But it may have happened in our neighbor, the Andromeda Galaxy, and astronomers almost missed it.

In 2014, NASA's Near-Earth Object Wide-Field Infrared Survey Explorer (NEOWISE) observed a star in Andromeda becoming more luminous in the infrared. Those observations were contained in the data collected by the telescope and only uncovered recently. A team of astronomers were filtering NEOWISE's data for variable sources and discovered M31-2014-DS1, a supergiant star in Andromeda that appears to have collapsed directly into a black hole.

The findings are presented in research titled "Disappearance of a massive star in the Andromeda Galaxy due to formation of a black hole." It's published in the journal Science, and the lead author is Kishalay De, an astronomy professor at Columbia University.

The researchers examined sequential images of M31 looking for variable sources. Images were taken every 6 months from 2009 to 2022. "Using the six-month cadenced observations from 2009 to 2022, we searched for luminous MIR transients that would accompany dusty stellar eruptions such as failed SNe," they explain. They found M31-2014-DS1, and over a two-year period beginning in 2014, the source increased its mid-infrared flux by 50%.

After two years of brightening, it faded below its initial flux in one year. The fading continued until 2022.

"This has probably been the most surprising discovery of my life," lead author De said in a press release. "The evidence of the disappearance of the star was lying in public archival data and nobody noticed for years until we picked it out."

The region is well-observed by other ground and space telescopes, and the researchers used those observations to retrieve optical light curves for the object. Between 2016 and 2019, its optical light faded by a factor of about 100. The object was undetectable in ground-based optical observations in 2023.

The Hubble happened to image it in 2022 and found nothing in the optical, and only a faint source in the near-infrared (NIR). Follow-up NIR observations and spectroscopy in 2023 with the Keck confirmed a faint NIR source.

"The dramatic and sustained fading of this star is very unusual, and suggests a supernova failed to occur, leading to the collapse of the star's core directly into a black hole," De said.

Whether or not a star collapses directly into a black hole without exploding as a supernova depends on neutrinos, according to the authors. When a massive star reaches the end of its life, its outward radiation can't support its own mass. The star's core collapses and releases neutrinos, and the neutrinos drive a shock wave into the star's outer layers, its stellar envelope.

If the shock is strong enough, the envelope is ejected and the star explodes as a supernova. "If the shock fails to eject it, the envelope is predicted to fall back onto the collapsing core, producing a stellar-mass black hole (BH) and causing the star to disappear," the researchers write.

The star started out with about 13 solar masses. Upon its death, it had only about 5 solar masses. It had shed most of its mass in its powerful stellar winds.

"Stars with this mass have long been assumed to always explode as supernovae," De said. "The fact that it didn't suggests that stars with the same mass may or may not successfully explode, possibly due to how gravity, gas pressure, and powerful shock waves interact in chaotic ways with each other inside the dying star."

Astronomers know of one other direct collapse black hole candidate. It was observed in 2010 in NGC 6946, a grand-design spiral galaxy about 25 million light-years away. But it's about 10 times more distant than M31-2014-DS1. The candidate is named N6946-BH1, and it's progenitor was also a supergiant star. It blossomed in luminosity then slowly faded, just like the object in Andromeda.

Unfortunately, since N6946-BH1 is so far away, it was much fainter and the observational data isn't as high quality as it is for M31-2014-DS1. But with this new discovery, N6946-BH1 is relevant again.

"We've known that black holes must come from stars. With these two new events, we're getting to watch it happen, and are learning a huge amount about how that process works along the way," said Morgan MacLeod, a lecturer on astronomy at Harvard and a co-author on the paper.

It took a lot of effort to find M31-2014-DS1. This work is the largest study ever done of variable infrared sources. They observed the stellar populations of the Milky Way and other nearby galaxies looking for objects like this, and found only one. While supernovae are hard to miss and announce their presence with months of extreme luminosity, direct-collapse black holes are the opposite.

"Unlike finding supernovae which is easy because the supernova outshines its entire galaxy for a few weeks, finding individual stars that disappear without producing an explosion is remarkably difficult," De said.

Astronomers almost missed this one, buried in mounds of astronomical data. The question is, how many more are out there? How common are they?

"It comes as a shock to know that a massive star basically disappeared (and died) without an explosion and nobody noticed it for more than five years," De said. "It really impacts our understanding of the inventory of massive stellar deaths in the universe. It says that these things may be quietly happening out there and easily going unnoticed."

Like many issues in astronomy and astrophysics, only a larger sample and better observations can advance our understanding of these direct-collapse black holes. The Vera Rubin Observatory has the potential find many more of them in its decade long Legacy Survey of Space and Time.

The original version of this article was published on Universe Today.

Last year, astronomers were fascinated by a runaway comet passing through our solar system from somewhere far beyond. It was moving at around 68 kilometres per second, just over double Earth's speed around the Sun.

Imagine if it had been something much bigger and faster: a black hole travelling at more like 3,000 km per second. We wouldn't see it coming until its intense gravitational forces started knocking around the orbits of the outer planets.

This may sound a bit ridiculous — but in the past year several lines of evidence have come together to show such a visitor is not impossible. Astronomers have seen clear signs of runaway supermassive black holes tearing through other galaxies, and have uncovered evidence that smaller, undetectable runaways are probably out there too.

Runaway black holes: the theory

The story begins in the 1960s, when New Zealand mathematician Roy Kerr found a solution of Einstein's general relativity equations that described spinning black holes. This led to two crucial discoveries about black holes.

First, the "no-hair theorem", which tells us black holes can be distinguished only by three properties: their mass, their spin and their electric charge.

For the second we need to think about Einstein's famous formula E = mc ² which says that energy has mass. In the case of a black hole, Kerr's solution tells us that as much as 29% of a black hole's mass can be in the form of rotational energy.

English physicist Roger Penrose deduced 50 years ago that this rotational energy of black holes can be released. A spinning black hole is like a battery capable of releasing vast amounts of spin energy.

A black hole can contain about 100 times more extractable energy than a star of the same mass. If a pair of black holes coalesce into one, much of that vast energy can be released in a few seconds.

It took two decades of painstaking supercomputer calculations to understand what happens when two spinning black holes collide and coalesce, creating gravitational waves. Depending on how the black holes are spinning, the gravitational wave energy can be released much more strongly in one direction than others — which sends the black holes shooting like a rocket in the opposite direction.

If the spins of the two colliding black holes are aligned the right way, the final black hole can be rocket-powered to speeds of thousands of kilometres per second.

Learning from real black holes

All that was theory, until the LIGO and Virgo gravitational wave observatories began detecting the whoops and chirps of gravitational waves given off by pairs of colliding black holes in 2015.

One of the most exciting discoveries was of black hole "ringdowns": a tuning fork-like ringing of newly formed black holes that tells us about their spin. The faster they spin, the longer they ring.

Better and better observations of coalescing black holes revealed that some pairs of black holes had randomly oriented spin axes, and that many of them had very large spin energy.

All this suggested runaway black holes were a real possibility. Moving at 1% of light speed, their trajectories through space would not follow the curved orbits of stars in galaxies, but rather would be almost straight.

Runaway black holes spotted in the wild

This brings us to the final step in our sequence: the actual discovery of runaway black holes.

It is difficult to search for relatively small runaway black holes. But a runaway black hole of a million or billion solar masses will create huge disruptions to the stars and gas around it as it travels through a galaxy.

They are predicted to leave contrails of stars in their wake, forming from interstellar gas in the same way contrails of cloud form in the wake of a jet plane. Stars form from collapsing gas and dust attracted to the passing black hole. It's a process that would last for tens of millions of years as the runaway black hole crosses a galaxy.

In 2025, several papers showed images of surprisingly straight streaks of stars within galaxies such as the image below. These seem to be convincing evidence for runaway black holes.

One paper, led by Yale astronomer Pieter van Dokkum, describes a very distant galaxy imaged by the James Webb telescope with a surprisingly bright contrail 200,000 light years long. The contrail showed the pressure effects expected from the gravitational compression of gas as a black hole passes: in this case it suggests a black hole with a mass 10 million times the Sun's, travelling at almost 1,000km/s.

Another describes a long straight contrail cutting across a galaxy called NGC3627. This one is likely caused by a black hole of about 2 million times the mass of the Sun, travelling at 300km/s. Its contrail is about 25,000 light years long.

If these extremely massive runaways exist, so too should their smaller cousins because gravitational wave observations suggest that some of them come together with the opposing spins needed to create powerful kicks. The speeds are easily fast enough for them to travel between galaxies.

So runaway black holes tearing through and between galaxies are a new ingredient of our remarkable universe. It's not impossible that one could turn up in our solar system, with potentially catastrophic results.

We should not lose sleep over this discovery. The odds are minuscule. It is just another way that the story of our universe has become a little bit richer and a bit more exciting than it was before.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

Moments after the Big Bang, the newborn universe was a wild, hot place. In that cosmic soup, primordial black holes — the first black holes in the universe, formed from extremely dense pockets of matter — could quickly take shape.

For ages, our understanding of these objects, especially the smaller ones, was that they eventually just faded away through a quantum process called Hawking radiation. It seemed like a settled fate.

But a new investigation, published in January to the preprint database arXiv, has opened a different path. This research claims that these objects didn't always shrink — sometimes, they could grow, becoming cosmic devourers that absorbed the radiation of the early universe.

This unexpected appetite doesn't just change the individual destinies of early black holes; it also transforms how we see the universe's past — and, crucially, it alters our search for dark matter, the invisible scaffolding that holds galaxies together.

Hungry newborns

Primordial black holes are a fascinating idea in cosmology. Unlike the usual black holes born from collapsing stars, these objects would have formed in the first moments after the Big Bang, from extreme densities in the universe's initial soup. They could range from microscopic sizes up to masses greater than that of the sun.

For a long time, general relativity told us that these objects, especially the smaller ones, would slowly lose mass through Hawking radiation. They would just evaporate and fade into nothing.

Here's where the story takes a turn. The early universe wasn't just a quiet vacuum around these primordial black holes; it was a thick, hot soup, full of radiation — with photons zipping everywhere.

This new research adds a vital piece to the puzzle: direct absorption of that thermal radiation. If a primordial black hole's collapse efficiency passes a certain point calculated in the new research, it doesn't just slowly evaporate; it starts to feed. These black holes become silent, hungry cosmic devourers, the new study suggests.

This new understanding changes everything about how we picture the early cosmos and the destiny of these ancient objects. Their ability to grow means they can live far longer than we previously thought, leading to extended lifetimes and substantial mass.

If primordial black holes can grow by absorbing radiation, then a much broader range of initial masses could still exist today, acting as the universe's unseen dark matter. The research indicates this expanded range depends heavily on something called the absorption efficiency parameter — a measure of how quickly and efficiently the black hole can feed on matter around it.

For instance, if this parameter is 0.3, the allowed range for a primordial black hole to form and become dark matter expands from 10^16 grams to 10^21 grams. If the parameter is 0.39, then the range is from 5*10^14 grams to 5*10^19 grams. Previously, it was thought that primordial black holes couldn't be this massive and still be responsible for dark matter.

This work makes us rethink a lot about the universe's earliest moments. It forces a fundamental reevaluation of how these objects evolve and their potential to explain the mystery of dark matter. This isn't just a small tweak to a model; it's a new chapter in our cosmic story. We thought we knew the life cycle of these objects, but it turns out, the universe had other plans.

Black hole quiz: How supermassive is your knowledge of the universe?

An impossibly powerful "ghost particle" that recently slammed into Earth may have come from a rare type of exploding black hole, researchers claim.

If true, the extraordinary event may prove a theory that could upend our understanding of both particle physics and dark matter, the team argues. However, this is just one theory, and there is no direct evidence to confirm that this is indeed what happened.

In early 2023, researchers at the Cubic Kilometre Neutrino Telescope (KM3NeT) — a massive, newly constructed array of sensors at the bottom of the Mediterranean Sea — detected a neutrino, a ghostly particle that has almost no mass and does not readily interact with most matter.

In addition to neutrinos' typical weirdness, this specific particle was noteworthy for its unusual intensity. It hit our planet with an estimated energy of up to 220 quadrillion electron volts, which is at least 100 times more powerful than any other neutrino detected to date and around 100,000 times greater than anything observed within human-made particle accelerators, like CERN's Large Hadron Collider.

Explaining the impossible

Researchers were initially unsure what caused this "impossible" neutrino to appear. It may have been birthed when a cosmic ray entered Earth's atmosphere, unleashing a cascade of high-energy particles that rained down on the planet's surface. However, its unprecedented power led experts to assume that it must have originated from some high-energy cosmic event that we don't fully understand.

In the new paper, which has been accepted for publication in the journal Physical Review Letters, one research group believes they have finally identified what really birthed the neutrino: an exploding, primordial black hole (PBH).

PBHs are a hypothetical class of black holes that are extremely small — potentially ranging from the size of an atom to a pinhead — and likely date back to the first moments after the Big Bang. The concept was first popularized by British physicist Stephen Hawking in the early 1970s, who also hinted that these miniature singularities would emit large quantities of high-energy particles, dubbed Hawking radiation, as they slowly evaporated. In theory, this would also mean they have the capacity to explode.

"The lighter a black hole is, the hotter it should be and the more particles it will emit," study co-author Andrea Thamm, a theoretical physicist at the University of Massachusetts Amherst, said in a statement. "As PBHs evaporate, they become ever lighter, and so hotter, emitting even more radiation in a runaway process until explosion."

One of the biggest mysteries surrounding the impossible neutrino, aside from its immense power, is that it was not observed by other neutrino detectors around the world, such as the IceCube Neutrino Observatory buried beneath Antarctica's icy surface. Given that PBHs are supposed to be fairly common throughout the universe, one would reasonably expect that similarly powerful particles also would have been detected before or since this possible discovery, especially as the number of neutrino detectors is quickly increasing.

The researchers said this is because the neutrino was emitted by a special type of PBH, dubbed a quasi-extremal PBH, which has a "dark charge" — a version of regular electric force that includes a very heavy, hypothesized version of the electron dubbed a "dark electron."

The dark properties of this theoretical type of PBH make it less likely that these black holes' explosions would be detected, the researchers suggested. It may also be that some of the less-powerful neutrinos detected to date may be partially incomplete detections of these events, they added.

"A PBH with a dark charge has unique properties and behaves in ways that are different from other, simpler PBH models," Thamm said. "We have shown that this can provide an explanation of all of the seemingly inconsistent experimental data."

Upending cosmic understanding

While the new research hints at the existence of quasi-extremal PBHs, it does not confirm them or prove that they explode as the researchers think. (Regular PBHs have never been directly observed, either, although there is a strong consensus that they exist.)

However, the team is confident that it will not take long to prove these dark explosions are real. The same research group recently predicted that there is a 90% chance we will see the first quasi-extremal PBH blow up by 2035, which would be extremely exciting for two main reasons.

First, these explosions would be so powerful that they would probably emit "a definitive catalog of all the subatomic particles in existence," including known entities, like the Higgs boson; theorized particles, like gravitons or time-traveling tachyons; and "everything else that is, so far, entirely unknown to science," the researchers wrote in the statement.

Second, these black holes could help reveal the mysterious identity of dark matter — the invisible stuff that we cannot see, yet whose gravitational force we can detect within almost every observed galaxy, including the Milky Way. The researchers wrote that quasi-extremal PBHs "could constitute all of the observed dark matter in the universe," so finding one could help put this mystery to bed. (Despite the similar names, dark matter is not directly related to dark charge or dark electrons.)

The researchers, along with several other teams in the fields of physics and cosmology, are now holding their collective breath to see when the first explosion might be detected.

This "incredible event" would provide a "new window on the universe" and help us "explain this otherwise unexplainable phenomenon," study lead author Michael Baker, a theoretical physicist at UMass Amherst, said in the statement.

A jet from a supermassive black hole is getting more energetic with time, and is now believed to be one of the most energetic objects in the universe.

The jet — nicknamed "Jetty McJetface" — is emanating from a black hole that was previously studied in 2022, after it picked up a star and began shredding it to pieces, releasing the jet in the process. Now, some four years later, that bout of "cosmic indigestion" is still going strong, researchers said.

"This is really unusual," Yvette Cendes, an astrophysicist at the University of Oregon who led the study published Feb. 5 in the Astrophysical Journal, said in a statement. "I'd be hard-pressed to think of anything rising like this over such a long period of time."

Many such star-shredding events have been spotted before, when a star gets too close to the gravitational field to a black hole and is violently torn apart in a process called "spaghettification." But such energy from spaghettification has never been seen before, Cendes said.

Cendes has a long affiliation with the black hole, formally known as AT2018hyz. (Her nickname for it, Jetty McJetface, is a pun on the British research vessel Boaty McBoatface, whose name was chosen by a viral Internet poll about 10 years ago.)

Cendes and her colleagues discovered the black hole in 2018, before publishing a paper in 2022 on the black hole's star-shredding behavior. Analysis of the radio waves blasting out of Jetty reveal that he black hole is roughly 50 times brighter than it was in 2019, emitting at least a trillion times the equivalent energy of the fictional Death Star of the "Star Wars" universe, according to the researchers.

New predictions suggest that the radio waves coming from the black hole will keep rising exponentially before peaking sometime in 2027.

Also, the team suggests the spaghettified star's radiation is blasting away from the black hole in a single direction, and likely not aimed at Earth. That may explain why the star wasn't seen near the black hole at first glance. But the team says more data will be required to verify that theory.

It's a well-known fact that supermassive black holes (SMBH) play a vital role in the evolution of galaxies.

Their powerful gravity and the way it accelerates matter in its vicinity causes so much radiation to be released from the core region — aka. an active galactic nucleus (AGN) — that it will periodically outshine all the stars in the disk combined.

In addition, some SMBHs accelerate infalling dust and gas into jets that emanate from the poles, sending streams of super-heated material millions of light-years at close to the speed of light.

Since the first of these "relativistic jets" was observed, scientists have been eager to learn more about them and their role in galaxy evolution. In a surprising first, a team of astronomers led by researchers at the University of California, Irvine (UC Irvine) and the Caltech Infrared Processing and Analysis Center (IPAC) recently uncovered the largest and most extended jet ever observed in a nearby galaxy.

Their observations also revealed vast "wobbly" structures, the clearest evidence to date that SMBHs can dramatically reshape their host galaxies far beyond their cores.

Their findings, published in the journal Science, were also the subject of a presentation made at the 247th Meeting of the American Astronomical Society in Phoenix, Arizona.

The team observed the galaxy VV340a using the W. M. Keck Observatory on Maunakea, Hawaii, and identified a jet extending up to 20,000 light-years from its center. Thanks to the Keck Cosmic Web Imager (KCWI) on the Observatory's Keck II telescope, they discerned a spear-like structure aligned with the galactic nucleus.

The data obtained from KCWI allowed the team to model the amount of material being expelled and determine whether the outflow could be affecting the galaxy's evolution. Said Justin Kader, a UC Irvine postdoctoral researcher and the lead author on the study, in a W.M. Keck Observatory press release:

The Keck Observatory data is what allowed us to understand the true scale of this phenomenon. The gas we see with Keck Observatory reaches the farthest distances from the black hole, which means it also traces the longest timescales. Without these observations, we wouldn't know how powerful — or how persistent — this outflow really is.

The team combined the Keck data with infrared observations made with the James Webb Space Telescope (JWST) and radio images from the Karl G. Jansky Very Large Array (VLA). While Webb's infrared data revealed the energetic heart of the galaxy, Keck's optical data showed how that energy propagates outward. The VLA radio data, meanwhile, revealed a pair of plasma jets twisted into a helical pattern as they move outward. The combined data presented a compelling picture, with a few surprises along the way.

For instance, the Webb data identified intensely energized "coronal" gas, the superheated plasma erupting from either side of the black hole, measuring several thousand parsecs across. Most observed coronae measure in the hundreds of parsecs, making this the most extended coronal gas structure ever observed. Meanwhile, the VLA radio data revealed a pair of plasma jets twisted into a helical pattern as they moved outward, evidence of a rare phenomenon in which a jet's direction slowly wobbles over time (known as jet precession).

In addition, the KCWI data showed that the jet arrests star formation by stripping the galaxy of gas at a rate of about 20 Solar masses a year. But what was most surprising was the fact that these jets were observed in a relatively young galaxy like VV340a, which is still in the early stages of a galactic merger. Typically, such jets are observed in older elliptical galaxies that have long since ceased star formation. This discovery challenges established theories of how galaxies and their SMBHs co-evolve and could provide new insights into how the Milky Way came to be. Said Kader:

This is the first time we've seen a precessing, kiloparsec-scale radio jet driving such a massive outflow in a disk galaxy. There's no clear fossil record of something like this happening in our galaxy, but this discovery suggests we can't rule it out. It changes the way we think about the galaxy we live in.

The next step for the team will involve higher-resolution radio observations to determine whether a second SMBH could be at the center of VV340a, which could be causing the jets' wobble. "We're only beginning to understand how common this kind of activity may be," said Vivian U, an associate scientist at Caltech/IPAC and the second and senior author of the study. "With Keck Observatory and these other powerful observatories working together, we're opening a new window into how galaxies change over time."

The original version of this article was published on Universe Today.

Colossal monsters lurk in the centers of all galaxies. Known as supermassive black holes, these gravitational beasts can have millions to billions of times more mass than the sun.

For decades, astronomers have wondered where these behemoths came from and how they got so huge. Early on, physicists thought that supermassive black holes formed like other, smaller black holes do — with large stars collapsing and becoming sun-size black holes that slowly devoured surrounding matter and merged with one another over billions of years.

But it has become increasingly clear this model is broken.

The James Webb Space Telescope (JWST) has peered back to some of the earliest epochs in cosmic history to spot gigantic black holes that are too big, too early to be explained by traditional models. Researchers are beginning to piece together a story of how they originated, which likely involved strange and exotic processes.

Emerging research suggests enormous black holes could have existed since the universe's earliest days, perhaps even before stars and galaxies, and that they came about in multiple ways. While future discoveries will help narrow down the predominance of each formation mechanism, many in the field are already thrilled to be chipping away at a long-standing cosmic mystery.

"This is one of the most exciting phases of my career," Roberto Maiolino, an astrophysicist at the University of Cambridge, told Live Science. "I'm tempted to call it a real revolution in our understanding of the formation of these objects."

Mystery giants

Hints of the cosmic size discrepancy arose in the early 2000s, when instruments like the Sloan Digital Sky Survey helped capture data on tens of thousands of extremely bright objects called quasars in the faroff universe. These luminous entities are thought to be gargantuan black holes in the centers of galaxies. They feed on vast amounts of gas and dust, and then spew powerful radiation. The Sloan survey showed that many quasars existed when the universe was just 800 million years old — a fraction of its current 13.8 billion-year age. The existence of these behemoths, which have millions to billions of times the sun's mass, was a head-scratcher for cosmologists.

That's because a typical black hole arises when a huge star nears the end of its life and explodes as a fiery supernova. The core of the titanic star collapses into a superdense point from which nothing, including light, can escape. Such stellar-size black holes are generally around 10 to 100 times as massive as the sun. While these objects can become gravitationally attracted to one another and merge into ever larger black holes, there didn't appear to be enough time for such processes to build them up into quasar-scale territory at the earliest points in cosmic history.

"We knew that either they grow very fast or there had to be some other ways of forming them," astrophysicist Ignas Juodzbalis, also of the University of Cambridge, told Live Science.

The question was how. One leading theory posits that, in the past, ginormous clumps of gas and dust could collapse under their own weight, rapidly forming a black hole with perhaps 1,000 to 1 million times the sun's mass. These direct-collapse black holes, as they're called, would then grow by feeding on gas and dust and merging into the supermassive black holes seen in today's galactic centers.

Models predicted that as such black holes gorged, they would become extremely bright compared with their host galaxies, either matching or topping surrounding stars' luminosities. In other words, they would become quasars.

In 2023, JWST spotted a distant galaxy, dubbed UHZ1, that seemed to align neatly with the direct-collapse black hole model. The galaxy existed when the universe was a mere 470 million years old and contains a black hole with an estimated mass of 40 million suns.

Astronomers lucked out because UHZ1 was spotted both by JWST, which sees in the infrared part of the electromagnetic spectrum, and by NASA's Chandra X-ray Observatory, which sees in X-ray light. Infrared light mostly comes from stars and warm dust heated by starlight, whereas the more powerful X-rays blast out from the devouring black hole.

And UHZ1's infrared and X-ray brightness are quite similar to one another, which suggests a black hole so large that it rivals the mass of all the stars in its galaxy. (For comparison, a modern galaxy like our Milky Way has around 20,000 times more mass in its stars, gas and dust than in its central black hole.) No one had ever seen anything like this before.

But researchers had predicted exactly how the colors emitted by a direct-collapse black hole would appear in JWST's instruments, along with several other key properties that could identify such an object .

"It turns out that UHZ1 remarkably satisfies all these properties," Priyamvada Natarajan, an astrophysicist at Yale University and lead author of the paper making those predictions, told Live Science.

Little red dots

UHZ1 is not alone. From almost the moment it turned on, JWST has been detecting extremely compact red entities that existed mainly when the cosmos was between half a billion and 1.5 billion years old. Known as "little red dots," they were originally thought to be galaxies far too big to have formed in the early universe, leading some scientists to call them "universe breakers" for upending models of cosmic history. The prevailing consensus is now moving toward the possibility that, rather than unusually large galaxies, these are bizarre, humongous black holes.

For instance, an object called QSO1 that existed when the universe was around 700 million years old has been studied intensely since it was discovered in 2023. A recent investigation looked at gas swirling around QSO1's center to try to pin down its mass with high precision. Swirling gas travels at a certain speed depending on the gravitational force tugging it as it spins. Using this technique, astronomers have shown that QSO1's mass is around that of 50 million suns. Moreover, all of the mass appears to be in a compact region around the black hole, with very little evidence of a large stellar population.

"We still don't see where the host galaxy is," Lukas Furtak, an astronomer at the University of Texas at Austin, told Live Science. "There doesn't really seem to be one."

This prospect — a gigantic black hole with no visible host galaxy — has been conjectured but never previously observed. Yet that appears to be what many of these little red dots are. Another recent study analyzed an object named "The Cliff," which likely weighs billions of times as much as the sun and is from about 1.8 billion years after the Big Bang. JWST's data showed a very sharp jump in The Cliff's light at a narrow wavelength that usually arises from dense hydrogen gas at a specific temperature. The findings indicate that The Cliff might be a long-hypothesized object called a quasi-star or a black hole star.

A quasi-star would be a potential stage in the evolution of a direct-collapse black hole. After the central huge chunk of gas crumpled to form a black hole, an outer sphere of gas and dust would remain, get heated by the black hole's emissions and glow in red wavelengths. This entity would look somewhat like a giant red star but would in fact be an envelope of hot hydrogen gas cocooned around a supermassive black hole.

In the very beginning

While direct-collapse models can explain a lot of what JWST is seeing, there remain a few other possibilities for supermassive black hole formation.

First proposed by Stephen Hawking in the 1970s, primordial black holes are a class of objects that could have arisen in the first few moments after the Big Bang, when dense regions collapsed under their own weight. Such black holes could come in a wide range of sizes, including ones large enough to act as the initial seeds for later supermassive black holes. One study has shown that mergers of primordial black holes could explain GN-z11, a galaxy from when the universe was a mere 400 million years old that contains a black hole with an estimated mass of 2 million suns.

Another theory has posited the existence of "not-quite-primordial black holes ." These would have come about within the first few million years after the Big Bang — later than primordial black holes but still long before any stars — when large clouds of hydrogen and helium collapsed under their own weight.

"For primordial black holes, you need these really extremely dense regions in the very early universe," Wenzer Qin, a theoretical physicist at New York University, told Live Science. That generally requires a lot of fine-tuning of parameters in a cosmological model, she added. When you relax such tight constraints a bit, dense regions appear at slightly later times in cosmic history, creating direct-collapse black holes that can go on to merge and end up as supermassive black holes.

Astronomers think that almost all elements heavier than hydrogen and helium were created in the nuclear bellies of giant stars and were then strewn about the universe when those stars went supernova. Many of the early black holes and young galaxies that JWST is seeing contain low amounts of these heavy elements. That could suggest that at least some of these objects formed from either primordial or not-quite-primordial black holes, given that both would have arisen long before any stars existed.

Researchers are still debating which of these models might be dominant for monster-black-hole formation, but most favor a blended view.

"I think, in the end, it will be some combination of all these mechanisms that gives rise to the entire population of supermassive black holes," Qin said.

Other missions such as the European Space Agency's Euclid observatory, launched in 2023, and NASA's Nancy Grace Roman Space Telescope, expected to launch in 2027, will team up with JWST to discover and study more early supermassive black holes. That should help researchers differentiate between these formation mechanisms and determine which, if any, is more common.

One thing that appears to be growing clearer to many astronomers is that supermassive black holes in the centers of galaxies probably didn't come from stellar-size ones.

Thanks to its unparalleled abilities, JWST has upended our understanding of early cosmic history and is helping to rewrite the story of how gigantic black holes may have developed.

"The universe is littered with supermassive black holes that form extremely early," Natarajan said. "I can't tell you how exciting that is."

Scientists have observed a supermassive black hole waking up from a nearly 100 million-year nap.

The black hole lies at the center of a gigantic galaxy that's emitting extremely strong radio waves. A new analysis of these radio emissions reveals the black hole once spewed gargantuan jets of plasma hundreds of thousands of light-years into space, before suddenly shutting off sometime in the distant past. Those jets are now active once again, and they are interacting in complex and chaotic ways with the superheated gas around them, according to the new study.

"It's 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," study co-author Shobha Kumari, an astronomer at Midnapore City College in India, said in a statement.

Galactic engine trouble

Only 10% to 20% of supermassive black holes have jets that emit radio signals. In these galaxies, a spinning disk of dust and plasma swirls around the black hole, regularly feeding it large amounts of matter. This infalling matter creates a tangled magnetic field that can fling some matter away from the black hole in giant jets. Changes in the disk can cause these radio jets to turn off and on in rare cases.

In the new study, published Jan. 15 in the journal Monthly Notices of the Royal Astronomical Society, the researchers used the Low-Frequency Array, a radio telescope network located primarily in the Netherlands, to find more than 20 galaxy clusters that housed radio galaxies with irregularly shaped jets. They focused on one such galaxy, called J1007+3540, with a particularly unusual footprint.

The giant galaxy has large, diffuse lobes of plasma that indicate past jet activity dating back some 240 million years. But within those lobes are smaller, brighter plasma jets that are just 140 million years old, the team found. That suggested that the active galactic nucleus (AGN) — the central region that houses a galaxy's supermassive black hole — had kicked back on after a period of silence.

"This dramatic layering of young jets inside older, exhausted lobes is the signature of an episodic AGN — a galaxy whose central engine keeps turning on and off over cosmic timescales," Kumari said.

The space between the galaxies in the cluster that includes J1007+3540 is filled with superheated gas known as the intracluster medium. That gas interacts with the radio jets, bending and shaping them as they extend from the AGN. One of the two older lobes is squished sideways and back toward its source by the surrounding gas. The other lobe has a long, kinked tail that suggests the intracluster medium is interacting with the jets in a different way.

"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," study co-author Surajit Pal, a physicist at the Manipal Centre for Natural Sciences in India, said in the statement.

Observing J1007+3540 will help researchers determine how often AGNs turn on and off and how old jets interact with their surroundings. In future work, the team plans to collect high-resolution observations of the galaxy to map how the jets propagate through the intracluster medium, according to the statement.

Astronomers have revealed the James Webb Space Telescope's (JWST) sharpest-ever image of the area around a black hole. The spectacular view could help solve a decades-long mystery while reversing a long-held belief about space's most extreme objects.

Since the 1990s, astronomers have observed a curious brightness in infrared wavelengths surrounding the active supermassive black holes (SMBHs) at the centers of some galaxies. Previously, they attributed these excess infrared emissions to the outflows — superheated streams of matter blasted from black holes.

But in a new study published Jan. 13 in the journal Nature Communications, an international team of researchers used JWST to look into the heart of the nearby Circinus galaxy, located only about 13 million light-years from Earth, to reveal the area around the galaxy's SMBH.

The data from JWST, paired with numerous ground-based observations, reveal that the infrared excess is coming from the disk of dusty material that's falling into the Circinus galaxy's central SMBH, rather than from material flowing away from it.

This galactic revelation can help astronomers better understand the growth and evolution of SMBHs, as well as these massive dark monsters' influence on their host galaxies.

Of doughnuts and disks

Active black holes like those at the centers of galaxies are fed by a giant ring of infalling gas and dust. As a black hole draws material from the inner wall of this "doughnut," known as a torus, the material forms a thinner accretion disk that spirals into the black hole like water spiraling into a drain.

The black hole's tidal forces accelerate the infalling matter to great speeds. The resulting friction within the disk causes the swirling matter to emit light that glows so brightly that it obscures astronomers' view of the inner region around the black hole.

Yet black holes are not vacuum cleaners, and even they have a feeding limit. So they blast some of the swirling material back into space, in the form of jets or "winds." Therefore, an understanding of the nature of a black hole's torus, accretion disk and outflows is key to knowing how black holes of various sizes accrete and expel matter to potentially shape their host galaxies by quenching or enhancing star formation across galactic scales.

Resolving a long-standing mystery

The dense gas and bright starlight in Circinus previously prevented astronomers from viewing the galaxy's central region and SMBH in detail.

"In order to study the supermassive black hole, despite being unable to resolve it, they had to obtain the total intensity of the inner region of the galaxy over a large wavelength range and then feed that data into models," lead study author Enrique Lopez-Rodriguez, a galaxy evolution researcher at the University of South Carolina, said in a NASA statement.

Earlier models separately fit the observed spectra of the torus, accretion disk and outflows, but they couldn't resolve the region in its entirety. As a result, astronomers could not explain which part of the SMBH's surroundings caused the excess emissions in infrared light.

JWST's advanced capabilities allowed astronomers to peer through the dust and starlight of Circinus so they could get a sharper view of the SMBH's environment. To do so, they used an imaging technique known as interferometry.

Ground-based interferometry generally requires an array of telescopes or mirrors that work together to gather and combine light from a celestial object over a large area. By combining light from multiple sources, this method causes the electromagnetic waves that form that light to create interference patterns that astronomers can analyze to reveal the sizes, shapes and other characteristics of those objects.

Unlike these terrestrial facilities, however, the space-based JWST can operate as its own interferometer array via its aperture masking interferometer (AMI), a component of the telescope's Near-Infrared Imager and Slitless Spectrograph (NIRISS) instrument. Like a camera aperture, AMI is an opaque physical mask with seven small, hexagonal holes that control the amount and direction of light entering JWST's detectors.

Overall, AMI effectively doubles JWST's resolution. "This allows us to see images twice as sharp," Joel Sanchez-Bermudez, an astrophysicist at the National University of Mexico and co-author of the study, said in the statement. "Instead of Webb's 6.5-meter [21 feet] diameter, it's like we are observing this region with a 13-meter space telescope."

By doubling its resolution, JWST captured its sharpest-ever view of a 33-light-year-wide area at the center of Circinus. This unprecedented image allowed researchers to calculate that the majority — around 87% — of the excess infrared emissions come from the dusty disk that's actively feeding the central black hole; "the inner surface of the hole of the doughnut," Lopez-Rodriguez said via email. Whereas previous research had suggested that the excess may have come from hot dusty winds, or even the galaxy’s residual starlight, the team found that less than 1% of these emissions come from the energetic outflows streaming away from the SMBH.

The accretion may be extinguishing star formation in the center of Circinus, but confirming this will require a different type of JWST-based observation, Lopez-Rodriguez said.

An invaluable perspective

In addition to revealing previously hidden SMBH mechanics, this research highlights the potential of JWST-based interferometry for studying various celestial objects, including other active SMBHs at the cores of nearby galaxies. By increasing the sample size, astronomers hope to determine whether the infrared emissions from other SMBHs are due to their dusty disks or to their hot outflows.

"AMI has to be used — in order to get precious JWST time — on targets which cannot be done from the ground, or at wavelengths that are blocked by the Earth's atmosphere," study co-author Julien Girard, a senior research scientist at the Space Telescope Science Institute, told Live Science via email.

AMI-based observations can better illuminate our own solar system; they recently offered a detailed look at the volcanoes on Jupiter's hellish moon Io, Girard added. So AMI can observe diverse cosmic objects of varying shapes and sizes, from moons oozing with lava to black holes obscured by dust. In the future, it could help astronomers detect moons around prominent asteroids or reveal the orbits and masses of multistar systems, Girard added.

Scientists may have finally pinned down the nature of some of the most baffling objects in the night sky.

In a new study, researchers investigated the identity of "little red dots." These mysterious objects from the early universe have characteristics of both galaxies and supermassive black holes but don't quite fit the description of either.

The new study found that these enigmatic dots may be young supermassive black holes after all, cocooned in dense clouds of gas that mask telltale signs of their true nature. The researchers published their findings Wednesday (Jan. 14) in the journal Nature.

Little red dots were first observed by the James Webb Space Telescope (JWST) shortly after the spacecraft began collecting data in 2022. They were initially thought to be compact, star-filled galaxies, but they were present too early in the universe to have formed so many stars — at least under our current understanding of galaxy evolution.

Instead, other researchers suggested that the unusual objects might be early supermassive black holes. Light emitted by energized hydrogen atoms around the dots suggests that the gas is moving at thousands of miles per second, tugged along by the gravitational pull of the object at the center.

"Such extreme speeds are a smoking gun of an active galactic nucleus," meaning a hungry supermassive black hole at the center of a galaxy that's pulling in matter, Rodrigo Nemmen, an astrophysicist at the University of São Paulo in Brazil, wrote in an accompanying article published in the journal Nature.

But unlike supermassive black holes, little red dots haven't been observed emitting X-rays or radio waves. And regardless of whether the dots are black holes or early galaxies, they appear to have too much mass to have formed as early in the universe as they did.

Black hole metamorphosis

In the new study, the researchers looked closely at the light emitted from these objects to better understand their nature. The scientists studied spectra from 30 little red dots, each one collected by JWST's infrared instruments.

The light emitted from the little red dots closely matches the light that the team predicted would be emitted from a supermassive black hole surrounded by a dense cloud of gas. That gaseous cocoon could have trapped X-ray and radio emissions from the growing black holes, blocking them from reaching JWST.

When the team recalculated the masses of the little red dots under the new interpretation, they found that the dots were about 100 times less massive than previously thought. Together, the evidence suggests that little red dots are growing supermassive black holes that are accreting the surrounding gas.

"These are the lowest mass black holes at high redshift, to our knowledge, and suggest a population of young [supermassive black holes]," the researchers wrote in the study. (Redshift describes how light stretches toward the redder end of the electromagnetic spectrum as it crosses the expanding cosmos; a higher redshift signifies a more distant object.)

"With the corrected mass estimates, [little red dots] fit standard theories of cosmic evolution," Nemmen wrote. Confirming the findings will involve studying more little red dots to explore whether this "cocoon" phase is common, and determining what role it plays in black hole growth.

New observations of a strange galaxy show it was slowly starved to death by its own black hole.

Two telescopes peered deep into space at the galaxy GS-10578, nicknamed "Pablo's Galaxy," after the name of the astronomer who previously studied it. The galaxy is large for its age: roughly 200 billion times the mass of the sun, with most of its stars lighting up between 11.5 billion years and 12.5 billion years ago. (For reference, the universe is roughly 13.8 billion years old.)

To scientists' surprise, they learned a supermassive black hole embedded in the galaxy slowly removed the cold gas needed for stars to grow, instead of (as models predict) tearing the galaxy apart.

"Pablo’s Galaxy appears to have 'lived fast and died young'," researchers wrote about the new work, published in Nature Astronomy on Monday, in a University of Cambridge statement. "It stopped forming new stars, despite its relatively young age, due to an almost total absence of the cold gas stars need to form."

The research team described the death as happening "by a thousand cuts," because the black hole heated up gas moving through the galaxy. This meant any cold gas was choked off from resupplying the galaxy, making it more difficult for stars to form.

"There was essentially no cold gas left. It points to a slow starvation, rather than a single dramatic death blow," lead author Jan Scholtz, from Cambridge's Cavendish Laboratory and the Kavli Institute for Cosmology, said in the statement.

The results came by analyzing data from both the James Webb Space Telescope, as well as the Atacama Large Millimeter Array (ALMA). ALMA revealed no traces of carbon monoxide, which is an indicator of cold, star-forming hydrogen gas, in the galaxy. JWST, meanwhile, showed the supermassive black hole shooting out neutral gas at 400 kilometers per second (nearly 900 mph). At such rates, the galaxy would have run out of star fuel in only 16 million to 220 million years, a fraction of the typical billions of years for stars to die out.

Pablo's Galaxy appears to be representative of galaxies from the young universe that appear to be aging faster than expected. "Before Webb, these were unheard of," Scholtz said. "Now we know they're more common than we thought – and this starvation effect may be why they live fast and die young."

What if some of the alien worlds we've discovered are not actually planets at all?

Astronomers have spent years cataloging thousands of worlds orbiting distant stars, assuming that if something has the mass of a planet and exerts a gravitational pull on its parent star, it must be a planet.

But there may be a ghostly alternative lurking in the early universe. In a recent paper that was uploaded to the arXiv preprint server but has not been peer-reviewed, researchers suggest that some "exoplanets" we've detected might actually be something far more exotic — primordial black holes.

These are not your garden-variety black holes, born from dying stars. Instead, they are hypothetical leftovers from the Big Bang itself, formed when the newborn universe was a chaotic, high-pressure soup of energy. These "mini" black holes could have the mass of Earth or Jupiter but be the size of a grapefruit.

Our current methods for finding planets are exceptionally good at measuring mass but less so at determining the physical size of a planet. For example, we often use the radial velocity method — a technique that involves watching a star "wobble" because the gravity of an orbiting object is yanking on it. If the wobble is big, the object is heavy. If the wobble is small, the object is light.

But here's the catch: A planet with the mass of Neptune and a black hole with the mass of Neptune produce the exact same wobble.

In an attempt to separate the two, the authors of the new study looked at exoplanets that have been detected via these wobbles but have never been seen crossing the face of their star — a process called a transit. When a planet transits, it blocks some light, telling us its physical size. If an object pulls on a star but never blocks any light, it might be because it is too small to see, or it might be because it is a black hole.

The researchers identified several intriguing suspects, including Kepler-21 Ac, HD 219134 f and Wolf 1061 d. These objects are heavy enough to make their stars wobble, yet they remain invisible to our telescopes. The team pointed to microlensing events — brief flashes of light caused when a massive object passes in front of a distant star and acts like a magnifying glass — as potential hiding spots for these ancient nomads.

The authors admitted that these candidates are merely representative possibilities, rather than a definitive gallery of tiny black holes. Most will likely turn out to be ordinary planets that just happen to have tilted orbits that prevent them from transiting.

The next decade of data from missions like the Nancy Grace Roman Space Telescope — a NASA telescope that will take a broad survey of exoplanets, due to launch as soon as this fall — will be crucial for learning more about these objects. We might catch one evaporating via Hawking radiation, a theoretical process whereby black holes slowly leak energy until they vanish. If so, we might discover that the universe is a lot more crowded with ancient black holes than we ever imagined.

A shock wave, far away in space, might be the telltale sign of the first confirmed "runaway" supermassive black hole, escaping its host galaxy at 2.2 million miles per hour (3.6 million km/h).

The potential confirmation by the James Webb Space Telescope (JWST), published on the preprint server Arxiv on Dec. 3, has not yet been peer-reviewed. But it has been submitted to Astrophysical Journal Letters and lead study author Pieter van Dokkum, a professor of astronomy and physics at Yale University, has published several peer-reviewed papers about candidate supermassive black holes in recent years.

Van Dokkum says this is the first confirmation of a runaway supermassive black hole, following five decades of theory and research about these objects. "The obvious next step is to look for more examples," he told LiveScience.

Tracing a stream of stars

The candidate black hole was first spotted back in 2023 by van Dokkum's team, who saw a faint line in an archival Hubble Space Telescope image. The sight was so strange that the team followed up with fresh observations from the Keck Observatory in Hawaii.

Observations back then showed that the black hole has a mass of 20 million suns, and that the strange line was a "wake" of young stars stretching 200,000 light-years across space — twice the diameter of the entire Milky Way. The Hubble image captures a moment in time when the universe was roughly half its current age of 13.8 billion years.

"We suspected that this strange object might be a runaway supermassive black hole, but we did not have 'smoking gun' proof," van Dokkum said. So, for their new research, the team turned to JWST, a deep-space observatory that is unique in its "sensitivity and sharpness," van Dokkum said, "to see the bow shock that is created by the speeding black hole."

The resulting imagery astounded the team.

JWST's mid-infrared instrument rendered the shockwave, or bow shock, at the leading edge of the candidate black hole's escape with unprecedented clarity. "It's a bit like the waves created by a ship," van Dokkum said. "In this case, the ship is a black hole and very difficult to see, but we can see the 'water' — really, hydrogen and oxygen gas — that [the black hole] pushes out in front of it."

Van Dokkum was astonished. "Everything about this object told us it was something really special, but seeing this clear signature in the data was incredibly satisfying," he added.

Aside from JWST's sheer resolution, van Dokkum said his study showed that the observations matched Hubble's and Keck's data in different wavelengths of light. The data "all provide different pieces of the puzzle," he said, "and they fit together beautifully — exactly as predicted by theoretical models."

A supermassive mystery

Studying runaway black holes, like this candidate one, shows scientists more about how galaxies and black holes evolved, van Dokkum said. Most large galaxies have supermassive black holes embedded in their center, including our own Milky Way. Whether they can escape their tight galactic bonds is a longstanding mystery.

The only way that a supermassive black hole could be ripped out of its galaxy, according to van Dokkum, is if at least two of these black holes got extraordinarily close to each other, with the intense gravitational interaction "kicking" one out of place.

The new research suggests the candidate runaway was produced after at least two, and potentially as many as three, black holes all interacted. With masses of at least 10 million suns each, van Dokkum said the violence of the encounter must have been "quite something."

As for where to look next for a runaway supermassive black hole, the research paper notes "several promising candidates," but the interpretation of these systems is difficult. One example is the ambiguous object known as the "Cosmic Owl," which is roughly 11 billion light-years away from Earth.

The Cosmic Owl, according to the new paper, includes two galactic nuclei — each with an active supermassive black hole at the galaxy's heart — and a third supermassive black hole that is, oddly, "embedded in a gas cloud" between the two galaxies.

How that third black hole arrived in a gas cloud is a matter of dispute. Some researchers say the black hole may be a runaway that escaped from one of the host galaxies, but JWST observations by van Dokkum's group challenge that interpretation. Their observations suggest the out-of-place black hole "more likely … formed in-situ through a direct collapse" of gas, produced by shockwaves after the two galaxies nearly collided with one another.

Further study is needed on this, and other objects that may contain possible black hole runaways. Van Dokkum cited the current Euclid and forthcoming Nancy Grace Roman space telescopes as promising survey instruments, since these telescopes are designed to look at the whole sky, unlike JWST. "That will tell us how often this happens — something we'd dearly like to know."

NASA's James Webb Space Telescope (JWST) has detected a supermassive black hole hiding in an ancient "Jekyll and Hyde" galaxy that changes its appearance depending on how you look at it.

The galaxy, nicknamed Virgil, looked like an ordinary star-forming galaxy when observed in optical wavelengths (the kind of light that human eyes and optical telescopes like Hubble can see). However, when JWST viewed the object in infrared via its Mid-Infrared Instrument (MIRI), a monster black hole became visible in the galaxy's core.

"Virgil has two personalities," George Rieke, an astronomer at the University of Arizona who co-led the discovery, said in a statement released Dec. 10. "The UV and optical show its 'good' side — a typical young galaxy quietly forming stars. But when MIRI data are added, Virgil transforms into the host of a heavily obscured supermassive black hole pouring out immense quantities of energy."

Rieke and his colleagues published their findings Nov. 17 in The Astrophysical Journal. The findings suggest that some of our universe's most extreme objects could be invisible unless observed in infrared wavelengths.

Light takes a long time to travel across the galaxy, so when a powerful telescope like JWST observes distant objects, it sees the objects as they appeared in the distant past. Basically, JWST acts like a time machine into the early universe. Virgil appears to JWST as it existed 800 million years after the Big Bang. (For context, the universe is thought to be around 13.8 billion years old.)

The researchers classified Virgil as a little red dot (LRD). This is the name given to mysterious red objects that appear in JWST observations of the distant, early universe, and that astronomers don't fully understand.

LRDs appear in large numbers at around 600 million years after the Big Bang, before rapidly declining at around 1.5 billion years after the Big Bang. Observing galaxies like Virgil should help researchers unravel the mysteries of LRDs, which have been linked to actively feeding supermassive black holes that are heavily obscured by dust.

JWST's Virgil observations also help researchers better understand how supermassive black holes grew in the early universe. The one at the center of Virgil was a so-called "overmassive" black hole — meaning a massive black hole that shouldn't be able to exist in a host galaxy of that size, according to the statement.

Astronomers used to think that black holes at the centers of galaxies grew at the same rate as their hosts, with the galaxies forming first and growing black holes over time as large quantities of matter coalesced at their centers. However, JWST observations like this one suggest that the opposite might be true — first comes the black hole, then the galaxy around it.

"JWST has shown that our ideas about how supermassive black holes formed were pretty much completely wrong," Rieke said. "It looks like the black holes actually get ahead of the galaxies in a lot of cases. That's the most exciting thing about what we're finding."

Astronomers have spotted a supermassive black hole whipping up cosmic winds at record speeds.

The black hole, located 135 million light-years from Earth in the center of the NGC 3783 spiral galaxy, caught researchers' attention after emitting a huge X-ray flare. As the burst died down, it left winds of more than 37,000 miles per second (60,000 kilometers per second) — one-fifth the speed of light — howling in its wake.

"We've not watched a black hole create winds this speedily before," Liyi Gu, an astronomer at Space Research Organisation Netherlands who led the research, said in a statement.

Gu and his colleagues were studying NGC 3783's active galactic nucleus (AGN), the bright, busy region surrounding a galaxy's feeding supermassive black hole. These areas are known to suddenly flare and belch jets of material and wind into space. The researchers think the intense X-ray burst and subsequent gale they observed was powered by the black hole's tangled magnetic field, which suddenly "untwisted."

The team likened the process to how Earth's sun releases enormous eruptions of plasma called coronal mass ejections shortly after our star's magnetic field lines tangle and snap. However, in this case, the supermassive black hole has the mass of 30 million suns, which puts its flares and ejections "on a scale almost too big to imagine," Matteo Guainazzi, a team member and European Space Agency (ESA) astronomer, said in the statement. (For reference, the winds from a recent coronal mass ejection clocked in at a paltry 930 miles, or 1,500 km, per second.)

The discovery was made using ESA's XMM-Newton and XRISM X-ray space telescopes. Gu's team used the two telescopes in tandem, tracking the initial flare with XMM-Newton's Optical Monitor, and analyzing the resultant winds with XRISM's Resolve instrument. The researchers hope to take a similar collaborative approach to investigate other flaring AGNs.

They also think studying AGNs and the intense flares they produce could help further our understanding of how galaxies evolve.

"Because they're so influential, knowing more about the magnetism of AGNs, and how they whip up winds such as these, is key to understanding the history of galaxies," Camille Diez, an astrophysicist and ESA fellow who was part of the research, said in the statement.

The scientists detailed their discovery in a paper published Dec. 9 in the journal Astronomy & Astrophysics.

Scientists using the James Webb Space Telescope (JWST) have spotted the first evidence of "monster stars" in the early universe — offering new clues to how supermassive black holes grew so big after only a billion years of the universe's history.

The team spotted these gargantuan stars — each with a mass of between 1,000 and 10,000 times our sun — in a galaxy called GS 3073, which formed roughly about a billion years after the Big Bang. It is believed that monster stars like these led to the formation of these early supermassive black holes.

The study was co-led by scientists from the Harvard-Smithsonian Center for Astrophysics (CfA) and the University of Portsmouth in the U.K., and was published Nov. 12 in Astrophysical Journal Letters.

"Our latest discovery helps solve a 20-year cosmic mystery," study co-author Daniel Whalen, from Portsmouth's Institute of Cosmology and Gravitation, said in a statement. "These cosmic giants would have burned brilliantly for a brief time, before collapsing into massive black holes, leaving behind the chemical signatures we can detect billions of years later."

"A bit like dinosaurs on Earth, they were enormous and primitive," Whalen added. "And they had short lives, living for just a quarter of a million years, a cosmic blink of an eye."

The research's implications include learning about the first generation of stars, as well as literally shedding light on the "cosmic dark ages", or the period of time when the first stars came to light and the chemistry of the universe began to change.

A peculiar signature

The stars in GS 3073 had an unusual and "extreme" imbalance of nitrogen to oxygen (a ratio of 0.46) not usually found in stars or stellar explosions, according to the team. The signature, however, matched something predicted in models: "primordial stars thousands of times more massive than our sun," study co-author Devesh Nandal, a postdoctoral fellow at the CfA's Institute for Theory and Computation, said.

How did these stars produce so much nitrogen? The researchers said it's a three-step process. Stars are constantly burning elements in their cores. As these large stars in GS 3073 burned helium, the chemical reactions created carbon. Eventually, carbon began to invade an outside shell of material, where hydrogen was burning. In that outside shell, the carbon and hydrogen then mixed to create nitrogen.

As the nitrogen was produced, convection currents within the star began to distribute it throughout the star's body. Over time, the nitrogen left the star and flowed into space. In the case of GS 3073, this process lasted millions of years.

"The study also found that this nitrogen signature only appears in a specific mass range," the researchers noted. "Stars smaller than 1,000 solar masses, or larger than 10,000 solar masses, don't produce the right chemical pattern for the signature, suggesting a 'sweet spot' for this type of enrichment."

The big black hole mystery

Based on their models, the researchers further suggested that when these monster stars reach the end of their lives, they don't explode into supernovas. What happens next is instead a big collapse, generating some of the universe's earliest supermassive black holes.

Adding more fuel to this idea: GS 3073 does appear to have an actively feeding black hole at its center, "potentially the very remnant of one of these supermassive first stars," the statement noted. "If confirmed, this would solve two mysteries at once: where the nitrogen came from and how the black hole formed."

The origin of the universe's first supermassive black holes remains one of the biggest mysteries in astrophysics. Some theories suggest they collapsed directly from ultra-dense clouds of gas shortly after the Big Bang and then formed galaxies around them; other theories point to more exotic explanations, such as dark matter interactions or the collapse of monster stars. Ultimately, more research is needed to solve this ancient puzzle.

About 3 billion years ago, a hapless star got caught in a twisted tug-of-war between two gigantic black holes — and now, we are seeing the faint screams of X-rays emanating from this violent event. If confirmed, it could be the most distant episode of two black holes attacking a star ever seen.

An international team of astronomers reported their decades-long observation of the faintest known variable X-ray flare in a paper accepted for publication in the journal The Innovation in November.

The X-ray source, named XID 925, was first spotted in 1999 within the Chandra X-ray Observatory's Deep Field South survey, the deepest and most complete X-ray survey ever taken. Since then, astronomers have kept a close eye on it, watching as what was initially a bright pinprick of radiation fell dimmer and dimmer, reaching just a paltry one-fortieth of its initially observed peak.

Making stellar spaghetti

A bright surge in X-rays followed by a long span of dimming is exactly what astronomers expect from violent encounters called tidal disruption events (TDEs), which happen when a star wanders too close to a supermassive black hole. Before the star is swallowed by the monster's event horizon (the point of no return), the black hole's enormous gravity rips the star to shreds — a process cutely dubbed "spaghettification," as if the star were being pulled into a thin strand of pasta.

The stellar material then settles into a thin, rapidly rotating disk just outside the black hole. The energy released by this process makes the gas so hot that it emits X-ray radiation that's visible even from the other side of the universe. Then, the material funnels its way to the gaping maw of the black hole itself, and the disk loses brightness.

XID 925 was already remarkable, as it was one of the most distant and faintest known TDEs ever recorded. But in 1999, it all went haywire.

Between January and March of that year, XID 925 rapidly and unexpectedly brightened by a factor of 27. Then, the X-ray brightness collapsed just as quickly as it appeared, and XID 925 continued to fade from the scene.

A back-to-back black hole attack

Now, the astronomers behind the new study believe there is another culprit behind this strange brightening. This is no simple case of a TDE around a single supermassive black hole. This is a case of a TDE around two supermassive black holes.

They argue that the unlucky star was caught in the gravitational embrace of a central gigantic black hole and another, smaller (but still large in its own right) companion black hole. The larger black hole tore apart the star and transformed it into an accretion disk. But then, the second black hole swung close to the disk, or even plowed right through it, and this disruption led to a furious burst of energies, the scientists explained.

Like a hapless car crashing into the scene of an accident, the event made a messy situation even messier — in this case, by triggering the release of even more X-rays. Once the smaller black hole moved on, the system returned to normal.

While the astronomers cautioned that this story doesn't perfectly explain all of the data, they argued that it's the most compelling scenario given what we know. If it is true, it would be the most distant known binary black hole tidal disruption event, giving us a crucial and exciting window into the complex relationships between stars and black holes in the hearts of young galaxies.

Astronomers using the James Webb Space Telescope (JWST) may have discovered the most distant supermassive black hole ever seen. The enormous object, hosted by the galaxy GHZ2, is so far away that astronomers see it as it was just 350 million years after the Big Bang.

The team's research, uploaded to the preprint server arXiv Nov. 4 but not yet peer-reviewed, used observations from JWST's Near Infrared Spectrograph and Mid-Infrared Instrument. These instruments cover a wide range of wavelengths and can detect ultraviolet and optical light originally emitted by the distant galaxy, which has been stretched into the infrared due to the expansion of the universe.

"GHZ2 exists at a time when the universe was extremely young, leaving relatively little time for a supermassive black hole and its host galaxy to grow together," Oscar Chavez Ortiz, a doctoral candidate in the Department of Astronomy at the University of Texas at Austin and the lead author of the study, told Live Science in an email. "In the local universe, black holes and galaxies clearly coevolve, but detecting such a system at this early epoch raises questions about how supermassive black holes gain mass so quickly."

There are two main hypotheses for how these supermassive black holes form so early, Chavez Ortiz said: They're either "light seeds" that grow extraordinarily fast, or "heavy seeds" that start with large masses, giving them a head start.

Secrets of the lines

Since GHZ2's discovery was reported in 2022, astronomers have used JWST to find many distant galaxies. However, GHZ2 stands out because its spectrum shows very intense "emission lines" — bright bands of light emitted by certain atoms or ions when their electrons get energized and then release energy at specific wavelengths. These lines carry clues about the processes powering GHZ2.

"We are observing emission lines that require a lot of energy to be produced, known as high-ionization lines," Jorge Zavala, an assistant professor in the Department of Astronomy at the University of Massachusetts Amherst and co-author of the study, told Live Science in an email.

Zavala explained that the current understanding of gas ionization — heating of gas that turns atoms into ions by losing or gaining electrons — is based primarily on nearby star-forming regions and usually doesn't account for the intense high-ionization lines. These lines, and the relationship between them, are often found in active galactic nuclei (AGN), which contain actively feeding black holes at their centers, with much more energetic radiation present.

A crucial clue was the detection of the C IV λ1548 emission line, which comes from triply ionized carbon — that is, carbon atoms that have lost three electrons. "Removing three electrons requires an extremely intense radiation field, which is very difficult to achieve with stars alone," Chavez Ortiz said. An AGN naturally produces such high-energy photons. The strength of this line strongly suggested that GHZ2 might host an actively feeding black hole, which motivated the researchers to do an in-depth analysis.

A mixed system

Because GHZ2 is an unusual system that challenges existing models, the researchers had to develop detailed models to match its unique behavior and understand the contributions of both stars and the AGN to the galaxy's light. This process involved testing and improving the models repeatedly to ensure they accurately represented the galaxy's properties.

Their analysis revealed that while the visible-light spectral lines could be explained by star formation alone, the particularly strong carbon line required the presence of an AGN. This finding suggested that some of the galaxy's light shows contributions from a hungry supermassive black hole.

However, Zavala noted that GHZ2 lacked some other indicators of an AGN. This means the galaxy may be powered mostly by stars — if those stars were supermassive, with masses hundreds to thousands of times that of the sun, or if star formation in GHZ2 happened very differently from what we currently understand.

Another possibility is that the galaxy's light comes partly from normal stars and partly from more exotic sources, like supermassive stars or an AGN.

To further confirm the AGN activity, researchers plan to obtain more JWST observations to collect higher-resolution spectra of some emission lines. Additionally, observations from the Atacama Large Millimeter/submillimeter Array that cover spectral lines in the far-infrared could improve the sensitivity of the dataset.

If confirmed, GHZ2 would host the most distant supermassive black hole ever identified. Detecting signs of AGN activity in this galaxy offers a rare natural laboratory to test competing "light seed" and "heavy seed" models of black hole formation and growth just a few hundred million years after the Big Bang.

Scientists have traced the origins of the most massive black hole merger ever observed, revealing how two "impossible" giants may have formed despite long-standing assumptions that such objects should not exist.

These black holes were considered "forbidden" because stars of that size were thought to blow themselves apart in extremely powerful explosions, leaving behind no remnant that could collapse into a black hole.

The new work shows that rapidly spinning, magnetized stars can collapse in unexpected ways, producing black holes inside this forbidden mass range, and setting the stage for the colossal merger event known as GW231123.

The findings also suggest that black holes can form more efficiently than scientists thought, which could transform our understanding of how the universe's first stars and black holes gave rise to today's supermassive black holes.

Why heavy black hole mergers matter

Black hole collisions have become one of the most important tools for understanding the universe.

"Black hole mergers allow us to observe the universe not through light, but through gravity — via gravitational waves produced by the distortion of space and time as black holes spiral together and merge," Ore Gottlieb, a professor at the Center for Computational Astrophysics who led the work, told Live Science in an email. Gravitational waves offer a rare view into regions of space where gravity is so extreme that not even light can escape. From the shape of the signal alone, scientists can infer the masses and spins of the merging objects and reconstruct how they formed.

These observations test Einstein's theory of general relativity where its predictions are the most demanding, because the space-time curvature around merging black holes pushes the theory to its limits. Events involving the heaviest black holes also reveal how massive stars lived and died across cosmic time and how early black holes grew into the monsters that sit at the centers of galaxies today.

The most massive black hole merger ever detected

When detectors recorded GW231123 in November 2023, astronomers quickly realized it stood apart. Two enormous objects — roughly 100 and 130 times the mass of the sun — had merged more than 2 billion light-years away. The surprise was that black holes of this size fall into what physicists call the "mass gap," a range between roughly 70 and 140 solar masses where no black holes were expected.

Stars in this range usually tear themselves apart through violent supernova explosions, leaving nothing behind. Yet GW231123 housed not one, but two such objects — and both showed signs of spinning at extreme rates. The event involved "two of the most rapidly spinning black holes, indicating a rare formation channel of massive and rapidly spinning black holes, which were not supposed to exist," Gottlieb said.

To unravel how such black holes could form, the team created detailed, three-dimensional simulations, starting from the life of an extremely massive star. The model followed a helium core about 250 times the mass of the sun as it burned fuel, collapsed, and formed a newborn black hole. Earlier theories assumed such a star would collapse in one piece, leaving a black hole as heavy as the original core. But the new study shows this is not always the case.

Solving the impossible

Gottlieb and colleagues found that rapid rotation changes everything.

"We showed that if the star rotates rapidly, it forms an accretion disk around the newly born black hole," Gottlieb explained. "Strong magnetic fields generated within this disk can drive powerful outflows that expel part of the stellar material, preventing it from falling into the black hole." Instead of swallowing the entire core, the young black hole loses access to much of the surrounding matter as magnetic forces blast material into space.

This mechanism reduces the final mass of the remnant, pushing it down into the mass gap — a region previously thought unreachable. "As a result, the final black hole mass can be significantly reduced, landing within the mass gap, a range previously thought to be inaccessible," Gottlieb said.

The simulations also naturally produced a link between the mass and spin of the resulting black hole. Strong magnetic fields extract angular momentum, thus slowing the black hole while ejecting more mass. Weaker fields leave a more massive, faster-spinning object. This relationship closely matches the properties inferred for the two black holes in GW231123. One would form in a star with moderate magnetic fields, and the other would form in a star with weaker ones, creating a pair with different final masses and spins — exactly what the gravitational wave signal suggests.

What these discoveries mean for gravity and cosmic history

Extreme events like GW231123 stretch general relativity to its breaking point.

"The tremendous curvature of space and time probes general relativity deep in its most extreme strong field regime, enabling us to test whether Einstein's equations remain accurate when gravity is at its most extreme," Gottlieb noted.

If similar events happened frequently in the early universe, they would have shaped the growth of the first black holes. Such mergers "imply that massive black holes can form more efficiently than current stellar models predict," Gottlieb said. "This would affect our understanding of how the first generation of stars and black holes seeded the supermassive black holes we observe in galaxies today."

The team's work points to a new formation pathway for massive black holes and predicts specific patterns astronomers can search for. "Our work opens a new window to black hole formation within the mass gap, predicting first-generation black holes (without previous mergers) at all masses," Gottlieb said. Future gravitational-wave detections will test whether the mass-spin correlation found in the simulations holds across many events.

"As we detect more massive black hole binaries, we will be able to test the predicted correlation on this population," Gottlieb said. These discoveries may reveal whether GW231123 is a cosmic rarity or the first clear sign of a hidden population of massive, rapidly spinning black holes.

Look into the night sky, and it might seem like space is a vast expanse of darkness. But are any regions darker than others? What's the darkest place in the solar system and, on a grander scale, the universe?

In short, the answer isn't straightforward, and it depends on whom you ask, experts told Live Science.

True darkness, the blackest black, is surprisingly rare and hard to pinpoint. This is because there is a lot of dust in the cosmos: Dust scatters light, making space glow far beyond stars, Marc Postman, an astronomer at the Space Telescope Science Institute (STScI) in Baltimore, told Live Science. As a result, there is a background glow that permeates much of the universe. (The color of the universe is actually "cosmic latte," a beige shade not too far off white.)

Darkness also "depends on how you define it," Andreas Burkert, a theoretical astrophysicist at the University of Munich, told Live Science. The visible light spectrum illuminates some places in the universe with light. However, other wavelengths on the electromagnetic spectrum, like gamma rays and ultraviolet light, touch almost everything. This means that space, when viewed in the full electromagnetic spectrum, is quite luminous.

Low albedos

If you consider only visible light, there are some exceedingly dark places in space. A number of factors contribute to this darkness.

Firstly, cosmic objects can be made of light-absorbing material, making them appear very dark. Scientifically, this is known as albedo, or the amount of light reflected off a surface. A perfect mirror, for instance, would reflect 100% of the light directed at it and have an albedo of 1, while charcoal has an albedo of 4%.

The nucleus of comet Borrelly (also called 19P/Borrelly) is one of the darkest spots in our solar system, according to the Guinness Book of World Records. The 5-mile-long (8 kilometers) comet is made up of dust and ice that reflects less than 3% of sunlight, based on an image taken in 2001.

Similarly, the darkest known exoplanet in the universe, TrES-2 b, reflects less than 1% of light, thought to be because of high amounts of sodium vapors and gaseous titanium oxide in the atmosphere. In contrast, Earth reflects about 30% of the sun's light.

Black holes, too, are dark because they capture light that crosses the event horizon. But interestingly, "that doesn't mean that there is no light," Burkert said. "It simply is trapped." As a result, "when you enter the black hole, it's actually extremely bright," he explained.

Blocking light and distant objects

Darkness can also exist if something is blocking light from nearby stars. For example, some craters on our moon, located at the poles, never see the sun's light. These places are very dark because they are in "permanent shadow," Postman said. The shadowed craters on Pluto can be quite dark as well, because of their distance away from the sun.

Far beyond that, dense dust clouds, called molecular cores or Bok globules, are also thought to be pitch black. They look like "a hole in the sky," Burkert said. This is because the globule, made up of a mix of molecular hydrogen, carbon oxides, helium and silicate dust, blocks nearly all visible light from surrounding stars, making them disappear. However, this light-blocking is not as profound in the infrared spectrum, Burkert noted, who has studied Barnard 68, a globule around 500 light-years away from Earth.

Finally, there are pockets of the sky that are dark simply because they are far away from any light source. These places were documented by NASA's New Horizons telescope, an instrument sent to take photos of the galaxy's outer corners.

Based on a 2021 paper published in The Astrophysical Journal, these faraway regions are very dark. "On average, the sky out there is 10 times darker than it is near the Earth," said Postman, who was a co-author on the study. However, these regions still had light from the background glow of the cosmos.

Burkert noted the Earth sits in a relatively dark cavity in the Milky Way, which uniquely allows us to have an unobstructed view far into space.

"We sit in the middle of this big bubble, and so we can see a lot of stars," Burkert said. "If we would not be in the bubble, maybe astronomy would not have developed. So [darkness] is a very relevant, I think, important idea and question."

A supermassive black hole appears to have generated a record flare after gobbling a star at least 30 times more massive than the sun.

The event has yet to be confirmed as a tidal disruption event (TDE), which happens when a black hole devours a star (or similar object) that strays too close to the black hole's gravity. But if verified, this TDE — called J2245+3743 — would be the most powerful and distant energy flare ever recorded from a supermassive black hole.

"If you convert our entire sun to energy, using Albert Einstein's famous formula E = mc2, that's how much energy has been pouring out from this flare since we began observing it," K. E. Saavik Ford, an astronomer at the City University of New York (CUNY), the Borough of Manhattan Community College and the American Museum of Natural History and a member of the research team, said in a statement.

The findings, reported Nov. 4 in the journal Nature Astronomy, would easily override the previous candidate record-holder. Nicknamed "Scary Barbie" (a character from the 2023 live-action "Barbie" film) in 2023, after its classification as ZTF20abrbeie, that earlier flare from a different supermassive black hole was estimated to have swallowed a star only between three and 10 times the mass of the sun.

Very far, and very bright

The newly published event emerged from a huge feeding black hole, also known as an active galactic nucleus (AGN). The supermassive black hole is believed to be more than 500 million times more massive than the sun. It is also quite distant, at 10 billion light-years away. (For comparison, the universe is about 13.8 billion years old.)

As astronomers watched the black hole over several months, the flare shined up to 30 times brighter than other flares seen before, with the brightness of about 10 trillion suns at its peak. The peak luminosity also varied by fortyfold during the observation period.

"The energetics show this object is very far away and very bright," lead author Matthew Graham, a research professor of astronomy at the California Institute of Technology (Caltech), said in the statement. "This is unlike any AGN we've ever seen."

Graham is also a project scientist for the Zwicky Transient Facility (ZTF), which first observed the event in 2018 from its site at the Palomar Observatory near San Diego. Several other telescopes in space and on Earth have been periodically watching the flare ever since.

When the research paper was written, the flare was still ongoing, although it was also fading. Graham said the flare is likely dimming because the star is not fully consumed yet, like "a fish only halfway down the whale's gullet."

The flare's luminosity is even more remarkable when compared with the roughly 100 other TDEs recorded so far. Most of the flares are at a similar brightness scale as a black hole's normal feeding activity, which makes them hard to spot. So J2245+3743's brightness came as a surprise because the flare was easily visible above its black hole's usual activity.

While the suspected massive star being shredded in the TDE would be a rare find, others are probably out there, the team said. The researchers plan to examine ZTF data for more events like this, and they said the newly completed Vera C. Rubin Observatory may spot some more as it scans the sky.

They're big, they appear early in the history of the universe and where they come from has long been a mystery. Ever since astronomers first detected the existence of supermassive black holes at the center of most galaxies, it has been difficult to fully explain their origin.

But a recent observation with the James Webb Space Telescope (JWST) could help solve the riddle of how supermassive black holes grew so rapidly to become the early universe's goliaths.

The object QSO1 lies in the galaxy cluster Abell 2744 (also known as Pandora's Cluster). The mass in the cluster acts as a gravitational lens that can focus and alter the light from distant sources, making them appear both brighter and at multiple locations. The light from QSO1 was emitted when the universe was around 700 million years old (its current age is almost 14 billion years).

The black hole in QSO1 was first analyzed in February 2024, which revealed that the galaxy contained a black hole with a mass roughly equivalent to 50 million suns.

A recent follow-up study led by Ignas Juodžbalis from the University of Cambridge confirmed the original mass estimate and also showed unequivocally that QSO1 lacks a significant component of gas and stars. Instead of being a black hole that sits at the center of a galaxy, it's as if the black hole itself is dominating the system and the wider galaxy is missing.

"It's a very odd system," Marta Volonteri, a professor at the Paris Institute of Astrophysics, said in an interview with LiveScience. "If there are more like that, it becomes really bizarre."

Volonteri is a world-leading expert on the formation of supermassive black holes and contributed to the analysis of the black hole's mass. "I double checked the results with my own code. There is very little room for any substantial mass in the system besides that of the black hole," she said.

In QSO1, the black hole's mass is about twice that of the surrounding gas and stars. In contrast, the black hole Sagittarius A*, which sits at the center of the Milky Way, has a mass that is only a tiny fraction of the total mass of the galaxy.

Mysterious little red dots

As JWST began gathering data in 2022, it revealed a surprising discovery: numerous compact, red-hued galaxies dubbed "little red dots" observed at epochs corresponding to roughly 500 million to 1.5 billion years after the Big Bang.

Their exact nature is still a mystery, but these ancient systems seem to indicate that galaxies, black holes or both evolved earlier, and with greater masses or densities, than astronomers had previously believed.

Black holes can form when massive stars exhaust their nuclear fuel and collapse under their own gravity. At the dawn of the universe, these early black holes would have grown by feeding on a buffet of stars, gas clouds and other black holes. Yet when astronomers calculate how quickly such stellar-mass black holes could accrete matter, they find it difficult to explain how they could have grown into the cosmic behemoths observed by JWST.

One alternative scenario is that instead of being created from stars, some early-universe black holes could have been formed from the direct collapse of huge gas clouds with much larger masses. Such a scenario was supported by the discovery of UHZ-1, a black hole that displays the telltale signs of direct collapse according to a study led by Priyamvada Natarajan from Yale University.

But the system QSO1, one of the several hundred little red dots that astronomers have analyzed, seems to have formed in a different way.

"My co-authors suggested that its origin could be a primordial black hole, or it may be dark matter that has collapsed because of how it interacts with itself," Volonteri said. "In any case, the black hole came well before the ordinary matter, such as the gas and the stars."

Primordial black holes

In 1967, the Soviet physicists Yakov B. Zeldovich and Igor D. Novikov proposed that, for a brief moment after the Big Bang, some regions of the universe contained so much mass that they imploded into black holes. The idea was further developed by Stephen Hawking in 1971, and has since been investigated both theoretically and observationally by several astrophysicists.

These primordial black holes would not only get a head start in terms of their growth and size, but also sit dead center in the galaxies that form around them. "That the black hole in QSO1 grew so much without any star formation taking place points to a case in which it developed significantly faster than the galaxy," Volonteri said.

The question, then, is if the discovery of QSO1 solves the chicken-or-egg problem of which came into being first: the galaxy, or the black hole at its center?

"This is one object that is still being reviewed. I hope that all this analysis is correct, but it's very complex. But what we used to call exotic models are perhaps not so exotic anymore," Volonteri concluded.

Marta Volonteri was previously interviewed by the author for the book Facing Infinity: Black holes and our place on Earth, which contains more information about her work and the origin of supermassive black holes. Read an exclusive excerpt here.

Thank your lucky stars for black holes. Mysterious, terrifying and endlessly fascinating, these extreme objects are the gravitational anchors of every large galaxy – including our own — and help regulate star formation across the cosmos. They are the darkest objects in the universe, and yet curious Earthlings are drawn to them like moths to a 100,000 solar mass flame.

In his new book "Facing Infinity: Black Holes and Our Place on Earth" (The Experiment, 2025), science writer and physicist Jonas Enander invites us on a journey through time and space to unravel the history, the science and the enduring mystique of black holes. From a volcano-top observatory in Hawaii that helped capture the historic first image of a black hole to a World War I battlefield in France where one of the most important astrophysical equations was conceived, Enander speaks with Nobel laureates and retraces the steps of some of the greatest thinkers in physics to help put these monstrous cosmic objects into a tangible, human context.

The journey begins at a terrifying end — with an unfortunate astronaut falling into a black hole's maw. Read an exclusive excerpt of "Facing Infinity" below.

The light blinds you.

You raise your hands to shield your eyes, letting fragments of light filter between your fingers. White, blue and red stars are shining brightly in the darkness.

You're floating in space. There's no up or down.

Thick white gloves cover your hands. They are part of your spacesuit, your only protection from the deadly vacuum that surrounds you.

You lower your hands and squint. In the starfield in front of you, you see a darkness. There are no stars there. There's no light, nothing but cold, black emptiness: a black hole.

A black hole is a place in the universe with such strong gravity no light can escape it. That's why black holes are dark. But the darkness not only signifies the absence of light, it also represents a limit of knowledge. No particles, no radiation and no other information can exit a black hole. If you want to know what is going on in the darkness, you have to travel right into it.

You realize that the darkness in front of you has grown. You are falling towards it and there is nothing you can do to stop yourself. You have no spaceship, no rockets, no way to alter your course.

The darkness feels both menacing and alluring. Like the explorers of old, you are venturing into the unknown. You are going to find out what happens in one of the strangest places in the universe, a place no one else has ever visited.

But there's a difference between you and those adventurers: after they had explored far-away places, they could return home and describe what they had seen. You will not be able to travel back and tell your fellow humans what you've been through. Once you've fallen into the black hole, you can never turn back. Its gravitational pull is too strong. The darkness will swallow you forever.

You're falling into an abyss of space and time that has an enormous gravitational pull. But falling in space is not the same as falling on planet Earth. On Earth you can feel the air rushing past your face and hear your clothes fluttering in the wind. In the emptiness of space, however, there is no air and no sound. All you can feel is your spacesuit bumping against your body, and all you can hear is your breath, though you start to perceive a thudding noise that has grown louder as the darkness has deepened. You realize it's the sound of your heart, beating harder and harder the closer you get to the black hole. It's as though your heart fears what you will meet in the darkness, as though it knows you will have to sacrifice something in order to see what is happening inside.

Knowledge comes at a cost. The greater the knowledge, the higher the price. To find out what happens in one of the darkest and most peculiar places in the universe, you will have to pay the highest price of all: your life.

The point at which this will happen depends on the size of the black hole. The larger it is, the longer you can survive. The black hole you are falling towards right now is almost as big as the solar system. You can pass through its surface painlessly, but after that, your life will be over in only a few hours.

Your field of vision is increasingly taken up by the dark sphere. As the darkness grows, the light around it seems to change. You see multiple copies of the light from the stars appear on either side of the black hole. At the same time, the stars' light seems to grow brighter, becoming compressed along the edge of the black hole. It occurs to you that the darkness is controlling the light. The black hole's powerful gravity is making the stars' light travel along peculiar paths that multiply its radiance. Phantom stars form in space, like mirages in the desert. These strange star-doubles disorient you. You want to tell your friends how the encroaching darkness fills you with terror, how the light of the stars is distorted and how helpless you feel. But even if you had a radio transmitter, you wouldn't be able to send your friends a message after you'd passed the event horizon. You will have to bear those final moments in the darkness alone.

Deep within the abyss, there is a point so extremely dense it is hard to wrap our minds around what goes on there. This point is called the singularity. Everything that passes the event horizon will ultimately reach the singularity. There, all matter and all light will be concentrated in a state that is so distorted, even space and time seem to cease to exist.

You are gaining speed as you fall towards the darkness. There is nothing you can do to avoid it. You turn your head and look around you. The area of space behind you is growing darker and darker. You lose your ability to orient yourself. You cannot tell where you came from, or how far you are from the black hole. Are you already inside it? You don't know. There's no sign at the event horizon that says 'You are now passing the point of no return.'

The dark sphere seems to surround you in every direction. You flail your arms and legs in a desperate attempt to escape your journey towards the singularity, but it's pointless. There's no escaping the singularity. All that happens is that you start sweating.

You close your eyes, take a deep breath and think about what awaits you. When you travel feet-first towards a black hole, your lower body will feel a greater force than the upper body. You begin to be pulled apart. But it doesn't happen the same way as on a torture rack; instead, everything in your body is drawn out, from your skeleton, your tendons and your muscles, all the way down to your nerves, cells and DNA. Luckily, you'll feel almost nothing when it happens. From the moment you first notice the pain shoot through you, less than a second will pass before you are decimated. But unlike on Earth, where a person's dead body can be buried, there will be nothing left of you. Your body will be dissolved into the darkness.

The smell of your own sweat fills your spacesuit. You try to take deep breaths, but hear yourself breathing faster and faster. Pain flashes from your feet to your head. You tense every muscle in a final attempt to stop your body being strung out.

You open your eyes. The light of a billion stars blinds you. They are outside the black hole, but their light has been concentrated into a thin ring inside it. The ring is caught between the darkness in front of and behind you. You are in the centre of the ring.

Before you can even scream, your last second of life has passed.

You’ve been torn apart by the darkness.

Excerpt from Facing Infinity: "Black Holes and Our Place on Earth" © Jonas Enander, 2025. Translation copyright © Nichola Smalley, 2025. Reprinted by permission of the publisher, The Experiment. Available everywhere books are sold.

Scientists have found two pairs of merging black holes, and they think the larger one in each merger is a rare "second-generation" veteran of a previous collision.

The two larger black holes' unusual behavior, observed through ripples in space-time called gravitational waves, was described Oct. 28 in The Astrophysical Journal Letters.

The telltale clue was twofold: In each merger, the larger black hole was spinning rapidly and was significantly more massive than the partner black hole it swallowed. The events were observed with the LIGO-Virgo-KAGRA Collaboration, a set of gravitational-wave detectors around the world aiming to observe space-shaking events like black hole mergers and neutron star collisions.

The results "provide tantalizing evidence that these black holes were formed from previous black hole mergers," study co-author Stephen Fairhurst, a professor at Cardiff University in the U.K. and a spokesperson for the LIGO Scientific Collaboration, said in a statement.

Back-to-back mergers

The research was based on two recently detected mergers that occurred just a month apart. Analyzing the gravitational wave signatures from these events allowed the researchers to infer the mass, rotation and distances of the black holes involved.

In the first event, on Oct. 11, 2024, scientists spotted two black holes — measuring six and 20 times the mass of the sun, respectively — colliding in a merger known as GW241011, roughly 700 million light-years from Earth. The larger black hole was one of the fastest-rotating black holes ever found.

The second merger, GW241110, was found on Nov. 10, 2024, with black holes that were eight and 17 times the mass of the sun. This merger was farther away, at 2.4 billion light-years. The larger black hole was also spinning opposite to its orbit, which has never been seen before.

Scientists say each of these mergers had novel properties, including that the bigger black hole in each merger was nearly double the size of the smaller one, and that the larger black holes were spinning oddly compared with the hundreds of other mergers observed through gravitational waves since the historic first detection by LIGO (Laser Interferometer Gravitational-Wave Observatory) in 2015.

The scientists suggested that the larger black hole in each merger previously coalesced in a process called a "hierarchical merger," which would happen in dense environments like star clusters, where black holes would frequently come near each other.

"This is one of our most exciting discoveries so far," study co-author Jess McIver, an astrophysicist at the University of British Columbia, said in the statement. "These events provide strong evidence that there are very dense, busy pockets of the universe driving some dead stars together."

Aside from the possible second-generation black hole finds, scientists said that the two mergers validated physics laws predicted by Albert Einstein more than a century ago and that the events are helping scientists learn more about elementary particles.

For example, GW241011 generated a clear signal that allowed scientists to see the larger black hole deforming as it spun, due to the black hole's rapid rotation. The resulting signature in the gravitational waves matched up with theories from Einstein, as well as from mathematician Roy Kerr, concerning rotating black holes.

That same event also generated a "hum" in the gravitational-wave signal, created because the larger black hole was much larger than the smaller one. (The hum is similar to musical instrument overtones, the collaborators stated.) This observation also helped confirm predictions from Einstein.

New images from the James Webb telescope have captured previously unseen details of the gargantuan jets shooting out of the famous black hole M87* — the first-ever black hole to be directly imaged by the Event Horizon Telescope.

The new James Webb Space Telescope (JWST) images, published Sept. 22 in the journal Astronomy & Astrophysics, have also revealed the clearest views yet of the massive counter-jet that's ricocheting through space in the opposite direction, the study authors found.

The jet of subatomic particles spewing out of the supermassive black hole at the center of the gigantic galaxy Messier 87 (M87), located 54 million light-years from Earth, is catapulting through space at almost the speed of light. Previous radio wavelength observations from the Very Large Array (VLA) in New Mexico revealed that the jet is shaped like a double-helix and is about 8,000 light years long.

Although supermassive black hole jets are somewhat common, "the M87 jet is special in the sense that it is fairly close by (on astronomical scales), and very bright across the spectrum," study co-author Jan Röder, an astrophysicist at the Institute of Astrophysics of Andalusia in Spain, told Live Science in an email. This makes it "an ideal laboratory to study jet physics," he said.

The black hole M87* is a supermassive black hole with an equivalent mass of about 6.5 billion suns. It was the first black hole to be directly photographed by the Event Horizon Telescope — an array of eight globally linked radio telescopes — in 2019.

The black hole and its jets have been frequently studied since then, with recent research finding that the cosmic monster is spinning at close to 80% of the cosmic speed limit, and that the magnetic fields surrounding the black hole have changed dramatically in just a few short years.

Previous research has peeked at the jet using various electromagnetic wavelengths, including radio waves, visible light, ultraviolet radiation, X-rays and gamma rays. But its structure at the infrared scale, which Röder said is key for connecting the radio and visible light images, was unknown.

Now, Röder and his team have used infrared images of M87 taken in June 2024 by JWST's Near Infrared Camera (NIRCam) to study the jet like never before. First, the team isolated the jet in the images by modelling the galaxy and then scrubbing away its light emissions; as well as any extra stars, dust and background galaxies. They then used these cleaned images to identify all the individual features of the jet at four wavelengths of infrared light.

The two shorter-wavelength images were particularly high definition, and captured one of the brightest sections of the jet, called HST-1, near the galaxy's core. Previous research modelled HST-1 using X-ray data and found it was made up of two light emitting regions. These images are the first direct observations confirming this structure, Röder said.

The two longer-wavelength images show a faint C-shaped counter-jet spurting from the core in the opposite direction of the main jet. While the counter-jet also appears in radio wave photos, Röder said that the clarity achieved in the infrared images was "very exciting."

Continuing to snap photos at different wavelengths will help scientists to understand how the jet interacts with its cosmic surroundings and what the jet and its opposite are made of. "With every new observation, we inch closer to the complete picture," Röder added.

For the first time ever, astronomers have imaged two black holes orbiting each other, finally offering visual proof for the existence of black hole pairs.

Spotted through the faint fluctuations of radio light captured by telescopes both on the ground and in space, the two black holes are locked in a 12-year orbit some 5 billion light-years from Earth.

The smaller black hole was captured with a jet of near-light speed particles twisting around like a rotating garden hose or a dog's wagging tail. The larger black hole, producing a bigger cosmic fountain known as the blazar OJ287, is a supermassive monster with a mass roughly 18 billion times greater than our sun. The researchers published their findings Oct. 9 in The Astrophysical Journal.

"For the first time, we managed to get an image of two black holes circling each other," study first author Mauri Valtonen, an astronomer at the University of Turku in Finland, said in a statement. "In the image, the black holes are identified by the intense particle jets they emit. The black holes themselves are perfectly black, but they can be detected by these particle jets or by the glowing gas surrounding the hole."

Black holes are born from the collapse of giant stars and grow by gorging on gas, dust, stars and other black holes. For some of these gluttonous space-time ruptures, friction causes the material spiraling into their maws to heat up and emit light that telescopes can detect, turning them into so-called active galactic nuclei (AGN).

The most extreme AGN are quasars — supermassive black holes billions of times heavier than the sun that shed their gaseous cocoons by shooting out light blasts trillions of times more luminous than the brightest stars. When these jets are pointed toward Earth’s line of sight, they are known as blazars.

Astronomers have previously imaged the supermassive giants at the center of our Milky Way and in the nearby galaxy Messier 87, and ample evidence for black hole binaries and their mergers appears in detections of gravitational waves. Yet despite long-held suspicions that OJ287 contained an orbiting pair, telescopes lacked the resolution to separate them from a single dot.

In fact, observations of OJ287 go back before astronomers even knew black holes existed; its semi-periodic flares in intensity were included in late 19th century photographic plates made to study nearby cosmic objects. Revisiting data taken from these plates and in follow-up observations led astronomers to begin speculating in the 1980s that the system's regular dimming and brightening was caused by two orbiting black holes.

To arrive at visual proof, the astronomers used a radio image obtained by a network that includes the RadioAstron, or Spektr-R, satellite — a Russian scientific satellite carrying a radio telescope operational from 2011 to 2019.

"The satellite's radio antenna went halfway to the moon, which greatly improved the resolution of the image," Valtonen said. "In recent years, we have only been able to use Earth-based telescopes, where the image resolution is not as good."

Comparing the features in the image to past calculations, the researchers distinguished two components corresponding to the jets of each black hole appearing exactly where the theory suggests they should.

Yet some wrinkles remain: The researchers caution that the two jets in the image could overlap, meaning that the possibility can't yet be fully excluded that there is only one.

"When the resolution close to that provided by RadioAstron is achieved again, in the future… it would be possible to verify the 'wagging of the tail' of the secondary black hole," they wrote.

Astronomers have observed a gigantic cosmic "contrail" in a distant galaxy. The trail of gas and dust may have been churned out by a passing massive black hole, although there are other possible causes, scientists report in a new study.

The contrail was spotted in the spiral galaxy NGC 3627, located roughly 31 million light-years from our solar system in the constellation Leo.

Although contrails have been previously identified in the Milky Way, NGC 3627's is the most clearly defined contrail ever discovered and is "remarkable for its sheer size," study co-author Mengke Zhao, a doctoral student in astronomy at Nanjing University in China, told Live Science in an email. The contrail is roughly 20,000 light-years long — about one-fifth the diameter of our entire galaxy — and extremely narrow, at only 650 light-years wide.

Zhao and co-author Guang-Xing Li stumbled upon the galactic contrail when analyzing data collected by the Physics at High Angular Resolution of Nearby Galaxies (PHANGS) survey. Using a range of telescopes, including the James Webb Space Telescope (JWST) and the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, this survey aims to study how gas and star formation influences, and is influenced by, galaxy structure and evolution. While the PHANGS-JWST data revealed that NGC 3627's contrail contains dust particles, the PHANGS-ALMA data suggested it was also rich in carbon monoxide.

The contrail is a faint, linear tail of gas and dust that appears distinct from the galaxy's two spiral arms. Based on a theoretical model Li co-developed in 2021, Zhao and Li think a massive compact object, like a black hole, was most likely responsible for creating it. The model suggests that as the object flew through the galactic disk, it squeezed out the gas, leaving behind the contrail marking its passage. The tremendous turbulence within NGC 3627's contrail supports this model.

The contrail's features allowed the researchers to estimate that the compact object was about 10 million solar masses and was zipping past at a breakneck speed of 186 miles per second (300 kilometers per second) — 50% faster than the current speed record for a spacecraft, held by the Parker Solar Probe. Additional calculations indicate the contrail formed 20 million years ago, relatively recently in astronomical terms. (The Milky Way is more than 13 billion years old, for comparison).

Although the researchers suggested the compact object could be an enormous black hole, they noted that it could also be the dense nucleus of a dwarf galaxy.

"Currently, with the available data, we cannot definitively distinguish between these two possibilities," Zhao said. "The predicted mass fits both scenarios. A direct detection of the object itself is very challenging — if it's a faint dwarf galaxy, it would be too dim to see easily at NGC 3627's distance. Future deep optical surveys or very high-resolution ALMA observations might one day reveal a counterpart."

The researchers also suggested that mysterious red and compact objects known as "little red dots" may also be responsible, although they haven't worked out exactly how.

Zhao and Li plan to continue studying the contrail and will search the PHANGS observations for more of these streams.

"Understanding their evolution and how common they are could tell us a lot about the population of massive dark objects flying through galactic disks," Zhao said.

The study, which hasn't been peer-reviewed yet, is available as a preprint on the arXiv server.

Editor's note: This article was updated at 11:00 a.m. ET on Oct. 9 to correct a typo. The constellation Leo is 31 million light-years away, not 31 light-years away, as was previously written.

Black holes are often seen as cosmic monsters that swallow anything unlucky enough to stray too close. But new research suggests they do not always win — some stars can skim the Milky Way's central black hole, Sagittarius A*; lose mass; and stagger away. Scarred but alive, these survivors shine brighter than before, leaving clues that astronomers are only now learning to read.

"Just as the moon pulls tides on Earth, a black hole tugs on a star with far greater force," Rewa Clark Bush, a doctoral candidate in astronomy at Yale University and lead author of the study, told Live Science in an email. Push too far, and the star unravels. Yet some withstand the strain. "One of the stars we modeled lost over 60 percent of its envelope but still retained enough core material that it survived and escaped," Bush said.

The authors think that by counting survivor stars, astronomers might measure how often Sagittarius A* feeds on nearby stars — and the number may help to explain how our galaxy's central black hole grew to 4 million times the mass of the sun.

"Black holes are like chickens in a coop that only eat what they are fed," Heino Falcke, a professor of astrophysics at Radboud University in the Netherlands, not involved in the study, told LiveScience in an email. "The study provides a new toolbox to find these marred stars and learn about the history of our galactic center black hole's feeding habits."

Brighter after the storm

The team used advanced 3D simulations to follow stars brushing past the Milky Way’s black hole and track their long-term evolution. The results, published Aug. 27 in The Astrophysical Journal Letters, showed that a near miss — known as a partial tidal disruption — can trigger a brilliant transformation. A survivor star may throw off ribbons of plasma, swell to many times its original size, and glow up to 10 times brighter for thousands of years.

The show, however, does not last. Surviving stars gradually shrink and begin to masquerade as ordinary stars. Their only giveaway is chemical: The violence dredges up helium and nitrogen from the core to the surface.

"You would need to take spectroscopic data," Bush said — breaking starlight into its component colors — "to notice anomalies that reveal the trauma."

Giuseppe Lodato, an associate professor of astrophysics at the University of Milan, not involved in the study, told Live Science in an email that although survivor stars are well known to astrophysicists, this study stands out for characterizing their brightness and chemical evolution over time.

A clue to the G objects

The study may also address a mystery that has lingered in the Milky Way's core for years. Astronomers have observed several fuzzy light sources known as G objects. These bodies move like stars yet look like diffuse clouds in infrared images. Survivor stars fit the description — they're swollen and wrapped in material blown off during disruption.

"It is very exciting how the authors make a link with the still mysterious and heavily debated G objects," Selma de Mink, scientific director at the Max Planck Institute for Astrophysics in Germany, not involved in the study, told Live Science in an email.

Spotting these stars is not an easy task. Sjoert van Velzen, an assistant professor at the Leiden Observatory in the Netherlands, not involved in the study, told Live Science in an email that even the most ambitious new surveys, such as those undertaken by the Vera C. Rubin Observatory, will reveal thousands of bright flares from complete tidal disruptions in distant galaxies, not the faint remnants that slip away.

"The galactic center is crowded, with stardust blocking most optical light," de Mink said. Infrared instruments such as GRAVITY, which she likened to thermal cameras piercing smoke, are better suited to identifying swollen stars that may hide among the puzzling G objects.

Astronomers are scratching their heads after detecting a bizarre, long-lasting cosmic explosion unlike anything previously observed.

The explosion was a series of repeated outbursts of high-energy radiation, known as a gamma-ray burst. These bursts, the most powerful known explosions in the universe, typically only last for milliseconds to minutes, yet this one was observed erupting for nearly an entire day in July.

Scientists can't explain the record-shattering duration of the event, which occurred outside of the Milky Way and is officially named GRB 250702BDE, according to a study published Aug. 29 in The Astrophysical Journal Letters. Gamma-ray bursts are usually caused by the death of a giant star, but they're typically singular events. This one is unlike any other in 50 years of gamma-ray burst (GRB) observations, according to study co-lead author Antonio Martin-Carrillo, an astrophysicist at University College Dublin.

"GRBs are catastrophic events so they are expected to go off just once because the source that produced them does not survive the dramatic explosion," Martin-Carrillo said in a statement. "This event baffled us not only because it showed repeated powerful activity but also because it seemed to be periodic, which has never [been] seen before."

Related: 'It gave me goosebumps': Most powerful gamma ray burst ever detected hid a secret, scientists say

NASA's Fermi Gamma-ray Space Telescope first recorded the burst on July 2. Researchers then discovered that the Einstein Probe, an X-ray space telescope run by the Chinese Academy of Sciences with European partners, had detected activity from it on July 1, almost a day earlier.

To study the burst in more detail, a team at the European Southern Observatory (ESO) turned to the Very Large Telescope, one of the world's most advanced optical telescopes located in Chile’s Atacama desert. While originally thought to have occurred inside our galaxy, the Very Large Telescope observations suggested the strange signal had come from beyond it, an observation later confirmed by the Hubble Space Telescope, according to the study.

The study authors explored several possible explanations for the unprecedented repeated explosion.

"If a massive star – about 40 times the mass of the Sun – had died, like in typical GRBs, then it had to be a special type of death where some material kept powering the central engine," Martin-Carrillo said.

Another possible explanation is that the radiation blasts were emitted when a star, potentially a white dwarf, was ripped apart by a black hole in what's known as a tidal disruption event (TDE). But in order to produce the continuing explosion, this wouldn't have been any ordinary black hole.

"Unlike more typical TDEs, to explain the properties of this explosion would require an unusual star being destroyed by an even more unusual black hole, likely the long-sought 'intermediate mass black hole,'" Martin-Carrillo said. "Either option would be a first, making this event extremely unique."

Intermediate-mass black holes are larger than the stellar-mass black holes (formed when massive stars collapse in on themselves) but smaller than the supermassive black holes at the center of most galaxies. Astronomers expect that stellar-mass black holes collide and merge over time to form intermediate-mass black holes, but they've proven incredibly difficult to locate.

The team behind the new study is monitoring the aftermath of the explosion and deciphering its cause. The next step will be determining the precise location of the explosion, which will help researchers measure how much energy it generated.

"We are still not sure what produced this or if we can ever really find out but, with this research, we have made a huge step forward towards understanding this extremely unusual and exciting object," Martin-Carrillo said.

Black hole quiz: How supermassive is your knowledge of the universe?

Astronomers have discovered a new object that could help shed light on mysterious "little red dots" that were first spotted by the James Webb Space Telescope (JWST) in 2022.

The newfound object, dubbed "the Cliff," suggests that the little red dots represent a totally new class of cosmic objects known as a "black hole star," the researchers say. This newly hypothesized object would essentially be a black hole feeding so rapidly that it lights up the thick cocoon of gas surrounding it, making it glow like a star.

Previously, astronomers had proposed alternative explanations for these tiny red objects. Initially, they were thought to be massive galaxies from the early universe, and later, they were linked to actively feeding supermassive black holes.

However, all of these theories are still evolving, so it's unclear whether the dots are exotic objects or simply a stage in the growth of galaxies or black holes. When they were first discovered, little red dots were dubbed "universe breakers" because they seemed too old to exist in the first few billion years of the universe. Therefore, astronomers looked beyond the standard types of known objects to find an explanation for what they might be.

They proposed two models. "One possibility is that Little Red Dots are extremely massive and compact galaxies with intense star formation, leading to very large stellar densities in their cores,"said Fabio Pacucci, an astrophysicist at the Harvard & Smithsonian Center for Astrophysics who was not involved in the new study. This scenario suggests that little red dots are tiny-but-dense galaxies and rich in stars and that they involve exotic, never-before-seen processes.

"The other possibility is that they host massive black holes at their centers, often appearing 'overmassive' compared to the stellar mass of their galaxies," he told Live Science in an email. In both cases, the redness would be due to the enormous dust surrounding the object.

The second explanation would mean that little red dots are galaxies that are powered by a massive black hole at their centers, like an active galactic nucleus (AGN). These black hole-fueled galaxies would be nothing like the other type of AGNs found in the early universe, known as quasars — extremely bright objects that are powered by large supermassive black holes and are easily detectable because they are not blocked by dust. The connection between these two types of populations remains unclear.

"Both explanations push the limits of our current understanding of early galaxy evolution," Pacucci said.

A "Cliff"-hanger

In the new study, published Sept. 10 in the journal Astronomy & Astrophysics, a team of astronomers led by Anna de Graaff of the Max Planck Institute for Astronomy looked at a peculiar little red dot that existed 1.8 billion years after the Big Bang.

This little red dot, whose light took almost 12 billion years to reach us, was discovered among many other little red dots identified in the Red Unknowns: Bright Infrared Extragalactic Survey (RUBIES) obtained with JWST.

In the light of this object, the researchers noticed a very sharp jump in the brightness called the Balmer break. While this kind of rise is common in the light of different objects, the kind of sharpness seen in this object's light could not be explained by massive galaxies or typical active galactic nuclei, researchers found. They identified it as an exaggerated version of a little red dot and dubbed it "the Cliff" for its sharp rise in the spectrum.

This unusually strong feature made astronomers wonder if they had seen something entirely new. The brightness of the object suggested a very energetic source, and the Balmer break originates from dense hydrogen gas at a specific temperature, de Graaff explained. These two hints led to the "black hole star" hypothesis.

"Black hole stars are [feeding] massive black holes that are surrounded by dense gas," de Graaff explained. When black holes accrete surrounding matter, they emit a lot of light, and therefore heat the gas, making it glow and thus look like a star.

"The key difference, of course, is that normal stars are powered by nuclear fusion, which is not happening here," de Graaff said. A black hole star can be thought of as a hot object wrapped inside an ultrathick blanket.

"The 'black hole star' hypothesis is certainly intriguing," Pacucci said. "This work is interesting because it tries to bridge unexplained observational features of Little Red Dots with such theoretical ideas."

Other little red dots may have similar signatures to the Cliff that may have gone undetected due to observational limitations, Pacucci said. However, the black hole star hypothesis is still at the beginning stage. Many more observations would be necessary to test the robustness of this scenario, and monitoring of these objects over time would help distinguish scenarios, Pacucci noted.

"We are not sure yet how they evolve into the black hole population that we see today," de Graaff noted. "Because the number of little red dots decreases toward later cosmic times, it must be a short-lived phase." Next, the team will use JWST to study brighter little red dots to understand the detailed structure of black hole stars.

If little red dots are, in fact, black hole stars, it could solve another puzzle. If black hole stars could grow at extremely rapid rates, it could explain the emergence of supermassive black holes very early in the universe.

The true nature of little red dots remains a mystery. If more cocooned black holes are discovered in the universe, researchers can find out if the little red dots are truly exotic black hole stars, a phase in a massive black hole's growth, or simply a stage of galaxy evolution.

Astronomers have spotted a monster black hole in the early universe that's gorging on matter at more than twice the theoretical limit. The discovery deepens the mystery of how some black holes born shortly after the Big Bang managed to grow so big, so fast.

Using NASA's Chandra X-ray Observatory — a powerful X-ray telescope at risk of being terminated by the Trump administration's proposed 2026 NASA budget — astronomers zoomed in on an ancient black hole called RACS J0320-35, which was born just 920 million years after the Big Bang.

Even in that early epoch of cosmic history, when the universe was about one-fifteenth its current age, the black hole was a whopper, swelling to roughly 1 billion times the mass of the sun, and growing rapidly.

According to a new analysis of the X-ray, infrared and optical radiation pouring out of the black hole, the supermassive monster appears to be growing faster than is theoretically possible, at 2.4 times the Eddington limit — a theoretical ceiling for how fast black holes can grow, based on the relationship between their outward radiation pressure and gravitational pull.

"It was a bit shocking to see this black hole growing by leaps and bounds," lead study author Luca Ighina of the Harvard and Smithsonian Center for Astrophysics said in a NASA statement.

This rule-breaking black hole isn't the first "super-Eddington" object discovered in the early universe, but studying it further could bring scientists closer to understanding why some ancient black holes seem to defy our best models of cosmology.

The research was published Sept. 8 in the The Astrophysical Journal Letters.

Beyond the limit

Black holes are cosmic objects formed from the collapse of giant stars, which effectively create gravitational sinkholes in space. They grow by merging with other black holes and by gorging on the vast amounts of matter that spill over their event horizon — the point beyond which nothing, not even light, can escape.

Related: 'Dramatic' changes spotted in first black hole ever imaged

As the largest black holes draw matter toward them at near light speed, they may form enormous rings of bright light or regurgitate energy into giant, lightsaber-like jets that pierce the cosmos. The brightest of these dyspeptic black holes are called quasars, and they can outshine entire galaxies with their radiation.

That makes quasars ideal targets for astronomers — and RACS J0320-35 is no exception. First discovered in a radio telescope survey before being targeted by Chandra in 2023, the monster black hole's bright emissions across the electromagnetic spectrum make it a "perfect laboratory" for studying black hole growth, the researchers wrote in the study.

The researchers observed the intensity of X-ray light blasting away from the black hole at different wavelengths, and then compared this to infrared and optical data to estimate the object's mass and growth rate. They found that the black hole must be growing by 300 to 3,000 suns' worth of matter every year, putting it beyond the Eddington limit for a black hole of its size. How the black hole can surpass this limit without becoming unstable remains a mystery.

With a sense of the black hole's growth rate and age, the researchers then worked backward to make assumptions about how the monster originally formed. They found that, given its ultrafast growth, it could have started life as many typical black holes do in the local universe — from the collapse of a large star with a mass less than that of 100 suns.

This finding, along with those of other potential super-Eddington black holes spotted by the James Webb Space Telescope in the early universe, hints that fast-growing black holes may be a more common feature of the ancient cosmos than our models suggest. Rapid eaters like these may also be more likely to emit gargantuan energy jets, as RACS J0320-35 does, the researchers added.

Further research into this black hole and others like it will help researchers unlock the mysteries of the universe's earliest black holes — namely, where did they come from, and how did they grow so fast?

"How did the universe create the first generation of black holes?" study co-author Thomas Connor, also of the Harvard and Smithsonian Center for Astrophysics, said in the statement. "This remains one of the biggest questions in astrophysics and this one object is helping us chase down the answer."

One of the first black holes ever imaged is even stranger than we thought, new images of its dramatically changing environment reveal.

The object, known as M87*, has experienced unexpected changes in its magnetic fields that are showing up in polarized light — meaning, light waves that are orientated in the same way (such as vertically, or horizontally).

Astronomers are closely studying the precious few images we have to learn more about the role of magnetic fields at black holes such as M87*. Ideally, one of the study co-authors told LiveScience, a "movie" of the black hole — a sequence of images taken as frequently as once or twice a week — may in the future better reveal the changes in magnetic fields, as that's how quickly M87* evolves.

"With only three images of M87*, we're just beginning to scratch the surface of its horizon-scale mysteries — but we're certain that we can," Sebastiano von Fellenberg, who was a scientist at Germany's Max Planck Institute for Radio Astronomy (MPIfR) when the research was carried out, told Live Science in an email.

A black hole comes to light

Images of M87* were so far obtained in 2017, 2018 and 2021 by the Event Horizon Telescope (EHT) collaboration — a global network of radio telescopes that just added two new observatories to its network in Arizona and France. As its name implies, the black hole resides at the center of the galaxy Messier 87 (M87), and is located 55 million light-years from Earth.

Related: Astronomers accidentally use rare 'double zoom' technique to view black hole's corona in unprecedented detail

Now EHT, in collaboration with MpiFR, is tracing the "dynamic environment" surrounding the black hole after analysis of these three images, the consortium wrote in a press release.

M87* is quite massive, more than six billion times the mass of the sun. The new polarization information provides scientists with data about how the magnetic fields around it are structured, and how strong those fields are.

As the theory goes, magnetic fields at supermassive black holes are situated in a disk of plasma (superheated gas) circling the black hole. These fields spin together into "magnetic towers" full of incredible energy.

That energy in turn propels matter along jets, which are stabilized by the magnetic fields and move at close to the speed of light. The jets come from a small area surrounding the black hole, but still have a large effect on the galaxy's star formation and energy distribution — both of which play into the galaxy's evolution.

Von Fellenberg, who is now a fellow at the University of Toronto-based Canadian Institute for Theoretical Astrophysics, said there are two main takeaways from the work: that the polarization has a lot of variability, but that the total intensity images (topographic images) of M87* remain consistent.

"Both of these outcomes are expected to some degree," he explained. Total intensity is related to how much gravitational potential a black hole has, which shouldn't change much in the few years in which the images were collected.

But polarization, he added, "traces the state of the matter and magnetic field in the accretion flow — and to some extent, along the base of the jet." As such, said von Fellenberg, "The changes we observe imply that each snapshot captures a different state of these properties, which is consistent with theoretical predictions."

A dramatic shift

One big surprise was a polarization measure observed in 2021, called angle β₂. Compared with previous readings in 2017 and 2018, this measurement "shifts so dramatically that it no longer aligns with the electromagnetic-energy flux from previous years," von Fellenberg said.

Or as officials put it in the press release, the polarization pattern "flipped direction" between the three images: the magnetic fields were spiraling one way in 2017, stabilizing in 2018, and then reversing in 2021.

Scientists are trying to explain why this happened. From physics, they know that the discrepancy can only be explained if they see no additional polarization changes caused by electrons or matter along the line of sight, called external Faraday rotation.

This leaves the team with four possible explanations: a change in the underlying magnetic field structure, a change in the degree of Faraday rotation, evolving contributions from different emission regions (such as the disk or jet), or a combination of the first three factors.

Black hole quiz: How supermassive is your knowledge of the universe?

Stellar black holes form from the collapse of massive stars at the end of their lives, typically weighing 3 to 50 times the mass of the sun. When a star runs out of fuel, it explodes in a supernova, leaving behind a region so dense that nothing can escape, not even light.

Primordial black holes, by contrast, are theoretical objects that could have formed less than a second after the Big Bang from extremely dense regions of the early universe. Unlike stellar black holes, they could be much lighter and are ancient relics from when the universe contained mostly hydrogen and helium.

While black holes are typically known for consuming everything around them, physicists have long theorised that they eventually explode at the end of their lives through a process called Hawking radiation. Previously, scientists believed such explosions occurred only once every 100,000 years. However, new research, published in the journal Physical Review Letters, suggests we might witness this extraordinary phenomenon much sooner than expected.

"We believe that there is up to a 90% chance of witnessing an exploding black hole in the next 10 years, the key is that our current fleet of space and ground based telescopes are already capable of detecting such an explosion," said Aidan Symons, a graduate student from the University of Massachusetts.

The black holes most likely to explode aren't the massive stellar remnants we typically think of, but rather the primordial black holes (PBHs.) As physicist Stephen Hawking showed in 1970, the lighter a black hole is, the hotter it becomes and the more particles it emits through Hawking radiation. As PBHs evaporate, they become ever lighter, and so hotter, emitting even more radiation in a runaway process until explosion.

The breakthrough came when the team of researchers started to question long held assumptions about black holes' electrical properties. While standard black holes have no electrical charge, the team explored what might happen if primordial black holes formed with a tiny electric charge involving hypothetical heavy particles they call "dark electrons."

A dark electron would be like a much heavier version of the regular electron, but interacting through dark electromagnetic forces instead of ordinary electromagnetism. In theoretical models called dark-QED, these particles would carry dark electric charge and interact via dark photons, potentially affecting how matter behaves around the black holes.

The research team made a different assumption about the electrical properties of primordial black holes. They postulate that their model shows if a primordial black hole forms with a small dark electric charge, it should be temporarily stabilized before finally exploding. This stabilization effect could dramatically increase the likelihood of observing such explosions, from once every 100,000 years to potentially once every decade.

An exploding black hole wouldn't just be a spectacular light show, it would provide scientists with a catalog of every subatomic particle in existence. This includes not only particles we've already discovered, like electrons, quarks, and Higgs bosons, but also currently undetected particles, perhaps even dark matter.

The team insist that while they're not guaranteeing an explosion will occur this decade, the high probability means we should be prepared. Fortunately, our current telescope technology is already capable of detecting the telltale signs of Hawking radiation from an exploding primordial black hole. If their calculations prove correct, we may be able to shed light on one of our oldest questions; where did everything come from?!

The original version of this article was published on Universe Today.

Scientists have measured the recoil velocity from a cataclysmic collision between two black holes for the very first time.

Gravitational waves are ripples in space-time first proposed to exist by Albert Einstein, and detected for the first time in 2015. Another first came in 2019, when scientists picked up a gravitational wave signal resulting from a violent merger between vastly different sized black holes. The size imbalance caused the newborn black hole to ricochet off into the universe in a phenomenon known as a "natal kick."

Now, astronomers have deciphered this gravitational wave signal, called GW190412, revealing that the collision caused the newly-merged black hole to shoot through space at more than 31 miles per second (50 kilometers per second) — fast enough to catapult it out of its original cluster of stars, researchers reported in the study, published on Sept. 9 in the journal Nature Astronomy.

"It's a remarkable demonstration of what gravitational waves can do," study co-author Koustav Chandra, an astrophysicist at Pennsylvania State University said in a statement.

Collision signals

When black holes careen toward one another they produce gravitational waves. But when one black hole is much more massive than the other, the gravitational waves produced look very different depending on the angle from which they are observed.

By looking from different angles, researchers can find the direction of the kick. Then, the kick’s speed can be determined by measuring the mass ratio and spin of the two original black holes — information that can also be determined from studying gravitational waves.

Related: Scientists detect most massive black hole merger ever — and it birthed a monster 225 times as massive as the sun

If the recoil from the collision is strong enough to slingshot the merged black hole from its star cluster, this prevents this new black hole from subsequently merging with other black holes and potentially forming a supermassive black hole — which can be 100,000 to 50 billion times the mass of the sun. This makes understanding the speed and direction of kicks essential for tracking the formation of supermassive black holes.

In 2018, study co-author Juan Calderón Bustillo and his colleagues figured out exactly how to measure the natal kick based on these gravitational wave signals. But their model had to rely on simulations, as no black hole merger resulting in a recoil had been detected at that point.

Then, on April 12, 2019, the Advanced LIGO detectors in Louisiana and Washington State and the Virgo detector in Italy recorded the GW190412 picked up a signal resulting from two stellar-mass black holes merging: One 29.7 times as massive as the sun and the other 8.4 times as massive.

Despite taking place more than 2.4 billion light-years away from Earth, the researchers used two angles relative to Earth to determine where the kick sent the newborn black hole. It raced away from its birth site, likely a dense grouping of stars called a globular cluster, at an astonishing 111,600 miles per hour (179,600 kilometers per hour). This speed would be more than enough to enable it to escape the cluster and become a runaway black hole.

"This is one of the few phenomena in astrophysics where we're not just detecting something," Chandra said. "We're reconstructing the full 3D motion of an object that's billions of light-years away, using only ripples in spacetime."

The team’s next steps will be to look for more black hole mergers to measure with both gravitational waves and visible light, a search that could yield deeper insights into how the cosmic monsters grow.