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?

Physicists' top theory about the nature of the universe may be wrong, a new study of strangely warped light suggests.

The new research looked into three leading theories of dark matter, the invisible stuff that makes up most of the universe and provides structure to most galaxies, though we still don't know exactly what it is.

For decades, cold dark matter (CDM) has been our leading theory for the universe's invisible scaffolding. It's a neat idea: tiny, slow-moving particles that interact only through gravity. But CDM has its problems. It struggles with explaining galactic anomalies and with describing the strange rotation curves of dwarf galaxies, for example.

To further test the nature of dark matter, scientists observe bent starlight from distant galaxies — a process called gravitational lensing — to find critical clues about their hidden architecture. And a new paper published Jan. 23 to the preprint database arXiv turned up something fascinating: This deep lensing analysis decisively disfavors smooth dark matter lens models and strongly prefers fuzzy dark matter (FDM) over both the standard CDM and the more exotic self-interacting dark matter model, which proposes that dark matter slightly sticks to itself.

If it can be bolstered by more evidence, this discovery reveals a fuzzier, more quantum-like reality that underpins everything we know.

Flavors of darkness

Astronomers often talk about different dark matter "flavors," with three major theories topping the menu.

In CDM — the leading theory — dark matter acts like a vast, invisible cosmic scaffolding. It's made of tiny, slow-moving particles. They clump together easily, forming large invisible structures, or "halos," and countless smaller clumps within them. These smaller clumps are subhalos, and they act as gravitational anchors for galaxies.

Self-interacting dark matter, meanwhile, suggests those invisible sand grains of CDM have a slight stickiness or friction when they bump into each other. This extra interaction means that within dense clumps, the particles can transfer energy. It makes the centers of the clumps smoother. It can also cause them to collapse differently.

The final, a la carte model of the universe is fuzzy dark matter. According to this theory, instead of being made of distinct particles, dark matter could be a quantum fog or soup made of incredibly tiny, superlight waves. Because of their wave nature, they can't form extremely sharp, small clumps like CDM. Instead, they create fuzzy, rippling patterns, like gentle waves on a pond. These still bend light, but in a more continuous, less-distinct way than solid clumps would.

A twisted spotlight

The new research, which has not been peer-reviewed yet, really shifts things. Scientists used gravitational lensing data from 11 galaxies — specifically from systems where light bends in particular, sharp ways — to analyze how light bends around massive objects.

The smooth dark matter lens models — the ones we expected from standard CDM — are decisively disfavored by the way light bends in the new dataset. Instead, the data show a strong preference for fuzzy dark matter over both CDM and self-interacting dark matter. This strong preference for fuzzy dark matter persisted even when the researchers made the lens models more complex, and after excluding systems that might be messed up by microlensing.

If fuzzy dark matter is the answer, it completely shifts our understanding of the universe's fundamental building blocks. It would mean dark matter is a quantum wave — that it is not made of discrete, slow-moving particles. Rather, the universe's invisible scaffolding would be more like a vast, cosmic ocean with gentle, rippling currents.

This really changes how astronomers think about galaxy formation and the structure of the cosmos. Our current models, which are based largely on CDM, would need a serious rethink. This also opens up a lot of new questions. Scientists need to figure out how this fuzzy stuff interacts with regular matter. They also need to know what these exotic particles really are.

We started this cosmic detective story trying to understand the universe's true identity, its unseen architecture. For a long time, CDM was the prime suspect — a solid, dependable theory. But the clues, especially from bent starlight, don't quite fit.

Now, with this clever new analysis, we have a compelling piece of evidence suggesting the universe's invisible foundation is far more exotic and quantum than we ever imagined. It's a reminder that the cosmos always has more secrets to reveal.

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.

Using the James Webb Space Telescope (JWST), astronomers have mapped the largest section of the universe's dark matter yet, deepening our understanding of how this mysterious substance shapes the cosmic landscape.

Dark matter is notoriously difficult to study because it does not interact with light. Astronomers can detect it only by looking at its gravitational effects on baryonic, or "ordinary," matter. Observations of these interactions reveal that there is about five times as much dark matter in the universe as normal matter.

The new study, published Jan. 26 in the journal Nature Astronomy, mapped a piece of sky in the Sextans constellation. Researchers pointed JWST at this space for 255 hours, constructing a picture of its visible matter, including stars, galaxies and cosmic dust. From these observations, they identified nearly 800,000 galaxies — 10 times more than ground-based telescopes have seen in the same region, and nearly twice as many as the Hubble Space Telescope has spotted there.

Next, the team charted how the mass of this area's invisible dark matter warped the space around it.

"Previously, we were looking at a blurry picture of dark matter," Diana Scognamiglio, an astrophysicist at NASA's Jet Propulsion Laboratory (JPL) and co-lead author of the paper, said in a statement. "Now, we're seeing the invisible scaffolding of the universe in stunning detail."

Where galaxies come from

This detailed map could give scientists a better idea of how dark matter has shaped the evolution of the universe.

Shortly after the Big Bang, dark matter and ordinary matter were probably evenly distributed throughout space. But over time, dark matter began to clump together. This, in turn, pulled the ordinary matter into increasingly dense pockets, where it eventually collected enough mass to spark star formation.

In this way, dark matter was instrumental in creating the current layout and matter distribution of the cosmos. "This map provides stronger evidence that without dark matter, we might not have the elements in our galaxy that allowed life to appear," study co-author Jason Rhodes, a senior research scientist at JPL, said in the statement.

Scognamiglio and her team plan to keep mapping dark matter in the future. They intend to use NASA's Nancy Grace Roman Space Telescope, which is scheduled to launch later this year, to study an area 4,400 times the size of the region from the new study. However, Roman's map of dark matter will be significantly less detailed than JWST's.

The structure of the local universe is surprisingly flat, according to new research, and this cosmic quirk may save our Milky Way from colliding with countless other massive, nearby galaxies — except one.

For decades, astronomers have made the puzzling observation that our nearest galactic neighbor, Andromeda, is speeding toward a possible collision with our galaxy, while other nearby galaxies are moving away from us. Now, a new study may finally reveal why: A vast, flat sheet of dark matter is drawing those galaxies into deep space.

Dark matter anchors and attracts visible matter, and the gravitational pull from the far-out dark matter sheet, which lies slightly beyond the bounds of Andromeda and the Milky Way, overwhelms the attraction between our galaxy and other neighboring galaxies, researchers reported in a paper published Jan. 27 in the journal Nature Astronomy.

"The observed motions of nearby galaxies and the joint masses of the Milky Way and the Andromeda Galaxy can only be properly explained with this 'flat' mass distribution," the researchers said in a statement.

Future simulations could further explain how gravity sculpts our surroundings and why the local universe looks the way it does.

Going with the flow

The motion of galaxies throughout the expanding fabric of space-time is known as the Hubble flow. It's mathematically described by Hubble's law, named after astronomer Edwin Hubble, who discovered the expansion of the universe in the 1920s. His eponymous law constrains an observational phenomenon: Galaxies are moving away from Earth at speeds that are proportional to their distance. The farther a galaxy is from our vantage point, the faster it seems to be receding.

So why is Andromeda, located 2.5 million light-years away, hurtling toward us at 68 miles per second (110 kilometers per second), while most other large, nearby galaxies are following the flow? Curiously, these receding galaxies appear to resist the immense gravitational attraction of our Local Group, which includes the Milky Way, Andromeda, the Triangulum Galaxy and dozens of gravitationally bound, smaller galaxies.

This universal enigma has endured for more than half a century. In 1959, astronomers Franz Kahn and Lodewijk Woltjer found evidence of dark matter situated around Andromeda and the Milky Way. They calculated that to reverse the initial expansion imparted by the Big Bang, these two galaxies would require a combined mass much greater than all their stars put together.

It turns out that a significant portion of the mass of the Milky Way and Andromeda is contained in dark matter halos that surround each galaxy and facilitate the galaxies' rapid approach toward each other.

However, this attraction does not seem to affect nearby galaxies outside the Local Group, where "material is actually moving away from the Milky Way faster than the Hubble flow," study co-author Simon White, director emeritus of the Max Planck Institute for Astrophysics in Germany, said in a statement.

"Thus, galaxies closer than [roughly 8 million light-years] are moving away from us slower than predicted by Hubble's Law, whereas galaxies farther than [that] are actually receding faster than predicted," White told Live Science via email.

Building a universe from scratch

To find out why, the researchers built their own universe. They ran a multitude of simulations to explore the interactions among dark matter, our Local Group, and the receding galaxies just outside it, to a distance of around 32 million light-years.

The simulations modeled the evolution of the local universe from the beginning of space-time, starting with the mass distributions observed in the cosmic microwave background, the oldest light in the cosmos, emitted when the universe was just 380,000 years old. The researchers then had the model reproduce certain salient characteristics observed in nearby galaxies, including the mass, position and velocity of Andromeda and the Milky Way, as well as the positions and velocities of 31 galaxies located just outside the Local Group.

This revealed that the mass just slightly beyond the Local Group, including both dark matter and visible matter, is distributed in a vast, flat sheet that stretches for tens of millions of light-years and continues beyond the boundaries of the simulation.

Because nearby galaxies are embedded in this flattened sheet of dark matter, any gravitational pull from our Local Group is counteracted by the gravitational pull from the more distant mass in the sheet, drawing them away from us.

"If the mass were distributed approximately spherically around the Local Group, rather than being flat, then the external galaxies would be moving away from us slower than predicted by Hubble's law for the cosmic expansion, because they would be slowed down by the gravitational pull of the Milky Way and Andromeda," White told Live Science. "Instead, the flattened distribution of the surrounding matter pulls these galaxies outwards in a way which almost exactly compensates for the inward pull of the [Milky Way] and [Andromeda]."

Equally important, the regions above and below the sheet are devoid of galaxies. Such sparse regions occur throughout the cosmos, and the deep Local Voids around our Local Group formed in areas where the initial density of the universe was a bit lower than average.

"As a result these regions expanded faster than average, and their matter was 'pushed' outwards," White said via email. "By the present day these low-density regions fill most of space and gravitational effects have concentrated most of their material into the 'walls' that separate them."

Reconciling experiments, observations and models

The location of the voids is essential. These sparse regions are where any existing structures would fall toward the Local Group; any galaxies there would indeed be moving toward us. So we don't see any other objects careening toward the Milky Way, as Andromeda is doing, because there simply aren't any galaxies there to do so.

Overall, when accounting for the vast sheet of mass, the simulations accurately modeled the distribution of nearby galaxies and the voids, thereby reconciling experimental results with astronomical observations of galactic motions as well as with the leading model of cosmology, known as lambda cold dark matter.

"We are exploring all possible local configurations of the early universe that ultimately could lead to the Local Group," lead study author Ewoud Wempe, a cosmologist at the University of Groningen in the Netherlands, said in a different statement. "It is great that we now have a model that is consistent with the current cosmological model on the one hand, and with the dynamics of our local environment on the other."

Interestingly, the researchers report that high-latitude galaxies farther out in the cosmos have been observed to be falling toward the flat sheet of matter at several hundred kilometers per hour. Finding additional structures infalling from the directions of the voids could lend further support to the results of this study.

Two of the universe's most mysterious particles may be colliding invisibly throughout the cosmos — a discovery that could solve one of the biggest lingering problems in our standard model of cosmology.

Those two elusive components — dark matter and neutrinos (or "ghost particles") — are ubiquitous throughout the cosmos, yet they remain poorly understood. In a study published Jan. 2 in the journal Nature Astronomy, an international team of researchers found evidence that dark matter and neutrinos may collide, transferring momentum between them in the process.

This surprising interaction may help to explain why the universe is less populated by dense regions, like galaxies, than predicted — in other words, the universe is less "clumpy" than cosmologists think it should be, the researchers said in a statement.

Dark matter and neutrinos remain a riddle

Dark matter is the mysterious, invisible substance that constitutes 85% of the matter in the universe. As its name suggests, dark matter does not emit light, so its existence has been only indirectly inferred from its gravitational influence, as observed in cosmological surveys.

Neutrinos are subatomic particles with infinitesimally low masses and no electric charge, so they very rarely interact with other particles. They're produced by various nuclear processes, including stellar fusion and supernovas, in prodigious quantities: Every second, approximately 100 billion neutrinos pass through each square centimeter of your body, Live Science previously reported.

Yet dark matter and neutrinos should not interact, according to the leading model of cosmology, known as the lambda cold dark matter model (lambda-CDM). This standard model aims to theoretically explain the large-scale structure of the cosmos.

Cosmological conundrum

However, this recent study provides new evidence that dark matter and neutrinos may interact after all, as other researchers have posited over the past two decades.

If dark matter and neutrinos do collide, and transfer momentum to one another in the process, this discovery would inspire a rethink of the lambda-CDM model. Such collisions could also help to explain the "S8 tension," a mismatch between the expected and actual "clumpiness" of the universe.

"This tension does not mean the standard cosmological model is wrong, but it may suggest that it is incomplete," Eleonora Di Valentino, study co-author and a senior research fellow at the University of Sheffield in the U.K., explained in the statement. "Our study shows that interactions between dark matter and neutrinos could help explain this difference, offering new insight into how structure formed in the Universe."

The mismatch stems from researchers' findings that the current cosmos isn't as packed together as predicted, based on observations of the cosmic microwave background (CMB) — the first light in the universe, emitted when the cosmos was only 380,000 years old.

"The statement that cosmic structures are 'less clumped' is best understood in a statistical sense, rather than as a change in the appearance of individual galaxies or clusters. It refers to a reduced efficiency in the growth of cosmic structures over time," study co-author William Giarè, a cosmologist at the University of Hawaii, told Live Science via email.

Unraveling multiple threads of evidence

The researchers tried to unite evidence from energy and density fluctuations in the CMB and from baryon acoustic oscillations (BAO) — pressure waves "frozen" in time from the beginning of the cosmos — with more recent observations of the universe's large-scale structure.

The early-universe data come from the Atacama Cosmology Telescope in Chile and the European Space Agency's space-based Planck telescope, which was designed to study the CMB. The later-universe data come from the Victor M. Blanco Telescope in Chile and the Sloan Digital Sky Survey, a two-decade effort to create a 3D map of millions of galaxies across more than 11 billion light-years.

The researchers also incorporated cosmic shear data from the Dark Energy Survey. Cosmic shear is the distortion of distant celestial objects due to weak gravitational lensing, which occurs when massive foreground structures bend the fabric of space-time and alter the paths of light traveling from those distant celestial objects to our detectors.

Finally, the researchers combined these data and modeled the evolution of the universe. When accounting for collisions between dark matter and neutrinos and the resulting momentum exchange, the simulations generated a model universe that better agrees with real observations.

There's reason to remain cautious, however, as the interaction between dark matter and neutrinos has only a 3-sigma level of certainty — meaning there is a 0.3% chance that this result is a fluke. Though short of the scientific gold standard of 5 sigma, it is significant enough to warrant additional research because, if confirmed, the interaction would prove a "fundamental breakthrough in cosmology and particle physics" — and a potential solution to the cosmic clumpiness quandary.

"The final verdict will come from upcoming large sky surveys, such as those from the Vera C. Rubin Observatory, and more precise theoretical work," research team leader Sebastian Trojanowski, a theoretical physicist at the National Centre for Nuclear Research in Poland, explained in a separate statement. "These will allow us to determine whether we are witnessing a new discovery in the dark sector or whether our cosmological models require further adjustment. However, each of these scenarios brings us closer to solving the mystery of dark matter."

NASA recently revealed the first pictures of its newly constructed Nancy Grace Roman Space Telescope, which could soon help researchers hunt for exoplanets, map the Milky Way and unravel some of the universe's biggest mysteries, such as the true nature of dark matter.

Experts have also revealed the most probable launch date for the next-generation spacecraft, confirming that it will likely lift off ahead of schedule — and could begin collecting data before the end of 2026.

Roman is NASA's next flagship space telescope, following on from the Hubble Space Telescope, which launched in 1990, and the James Webb Space Telescope (JWST), which launched in 2021. The orbital observatory is named after pioneering scientist Nancy Grace Roman — who served as NASA's first chief astronomer between 1960 and 1962 — and will work alongside Hubble and JWST, rather than replacing the existing telescopes.

New photos, released Dec. 4, show Roman standing upright in a clean room at NASA's Goddard Space Flight Center in Greenbelt, Maryland. The telescope is around 42 feet (12.7 meters) tall and weighs a hefty 9,184 pounds (4,166 kilograms). It began construction in February 2016, and the project has so far stayed within its initial budget of $4.3 billion, researchers say.

Once launched, Roman will be positioned around 1 million miles (1.6 million kilometers) from Earth at a Lagrange point — a fixed point relative to our planet where the gravity of two objects cancels out. Its specific Lagrange point will be Sun-Earth L2, where JWST and the European Space Agency's Gaia and Euclid space telescopes already reside.

"Completing the Roman observatory brings us to a defining moment for the agency," NASA Associate Administrator Amit Kshatriya said in a statement. "Transformative science depends on disciplined engineering, and this team has delivered — piece by piece, test by test — an observatory that will expand our understanding of the universe."

"With Roman's construction complete, we are poised at the brink of unfathomable scientific discovery," Julie McEnery, an astrophysicist at NASA Goddard and Roman's senior project scientist, said in the statement. "In the mission's first five years, it's expected to unveil more than 100,000 distant worlds, hundreds of millions of stars, and billions of galaxies."

What will Roman do?

Roman is equipped with two key instruments, which will define its objectives throughout its initial five-year mission. (Roman will likely remain operational beyond five years, but researchers have only planned what it will do until then.)

The first is the Wide Field Instrument (WFI), a 288-megapixel camera attached to a 7.9-foot (2.4 meters) mirror, capable of capturing high-definition photos of the outer solar system, the edges of the visible universe and anything in-between in infrared light too faint to be seen by human eyes.

One of Roman's main goals will be to create the most detailed map of the Milky Way's center yet in the Galactic Plane Survey, which will account for at least 25% of its total observing time. But it will also search the wider universe for things like distant galaxy clusters and giant "cosmic voids," which could help reveal the identity of dark matter and dark energy, NASA recently announced.

But the telescope's secret weapon is arguably its Coronograph Instrument, which will block out the light from distant stars, allowing WFI to snap photos of their surrounding exoplanets, which would normally be obscured by stellar glare.

As of September 2025, scientists have discovered more than 6,000 exoplanets in roughly 30 years. However, Roman is expected to find more than 15 times as many in half a decade, which would be a huge boon to scientists exploring the possibility of extraterrestrial life.

"The question of 'Are we alone?' is a big one, and it's an equally big task to build tools that can help us answer it," Feng Zhao, a researcher at NASA's Jet Propulsion Lab in California and the Roman Coronagraph Instrument manager, said in the statement. This device could "bring us one step closer to that goal," Zhao added.

In total, Roman is expected to collect more than 20,000 terabytes of data over the course of its initial five-year mission, which is equivalent to the storage space of around 3,000 iPhones: "The sheer volume of the data Roman will return is mind-boggling," Dominic Benford, a NASA researcher and Roman's program scientist, said in the statement.

When will Roman launch?

For years, Roman's prospective launch has been earmarked for May 2027, with some predicting this date would be pushed back, like other previous NASA missions. For example, JWST was originally planned to launch in 2014, according to the Planetary Society.

However, early last year, rumors began to spread that Roman would not only meet its deadline but may actually launch early.

And on Jan. 5, at the 247th Meeting of the American Astronomical Society in Phoenix, Arizona, project scientists confirmed that these rumors were true, revealing that, as it stands, the earliest likely launch date for Roman is Sept. 28, according to Space News.

Roman will launch onboard one of SpaceX's Falcon Heavy rockets from NASA's Kennedy Space Center in Florida, meaning it will need to be transported more than 900 miles (1,450 km) from Goddard before lift-off. This is scheduled to occur in June, and whether or not this happens on time will give us a better indication of how likely a September launch date really is.

Once Roman is in orbit, it will take approximately 90 days for mission scientists to carry out the necessary steps to start collecting data, according to NASA. Therefore, if the telescope does launch on Sept. 28, it will likely start collecting data around Dec. 27.

A record-breaking investigation, using a particle detector a mile underground in South Dakota, may have revealed new insights about dark matter, the mysterious substance believed to make up most of the matter in the universe.

Using the largest dataset of its kind, the experiment — called LUX-ZEPLIN (LZ) — constrained the potential properties of one of the leading candidates for dark matter with unprecedented sensitivity. The research did not uncover any evidence of the mysterious substance, but will help future studies avoid false detections and better hone in on this poorly understood piece of the universe.

"This quest is to try to solve this huge problem, this huge missing piece that we have in terms of understanding our universe," Rick Gaitskell, head of the particle astrophysics group at Brown University and part of the LZ research team, told Live Science.

The results, released Monday (Dec. 8), have been submitted to the journal Physical Review Letters and are available as a preprint via arXiv. The results were also presented at a scientific talk at the Sanford Underground Research Facility, where LZ's detector is hosted.

WIMPs vs. neutrinos

The team had two goals for the new study: to elucidate the properties of a low-mass "flavor" of proposed dark-matter particles called weakly interacting massive particles (WIMPs), and to see if the detector could view solar neutrinos — nearly mass-less subatomic particles produced by nuclear reactions inside the sun. The team suspected that the detection signature of these particles could be similar to that predicted by certain models of dark matter, but needed to spot the solar neutrinos to know for sure.

Before the experiment, which took 417 days to perform between March 2023 and April 2025, the detector's sensitivity was upgraded to search for rare interactions with fundamental particles. A cylindrical chamber filled with liquid xenon was the theater for action. Researchers could watch for either WIMPs or neutrinos colliding with the xenon, either of which produces flashes of photons, along with positively charged electrons.

The experiment pushed forward the science for both the WIMP and neutrino questions. For the neutrinos, researchers improved their confidence that a type of solar neutrino, known as boron-8, is actually interacting with the xenon. This knowledge will help future studies avoid false detections of dark matter.

Physics discoveries typically must reach a confidence level called "5 sigma" to be considered valid. The new work achieved 4.5 sigma — a considerable improvement over sub-3-sigma results reported in two detectors last year. And that was especially notable given that boron-8 detections happen only about once a month in the detector, even when monitoring 10 tons of xenon, Gaitskell said.

As for the dark matter question, however, the researchers didn't find anything definitive for the low-mass types of WIMPs they were seeking. Scientists would have known it if they saw it, the team said; if a WIMP hits the heart of a xenon molecule, the energy of the collision creates a distinctive signature, as best as models predict.

"If you take a nucleus, it is possible for dark matter to come in and actually simultaneously scatter from the entire nucleus and cause it to recoil," Gaitskell explained. "It's known as a coherent scatter. It has a particular signature in the xenon. So it's those coherent, nuclear recoils that we're looking for."

The team did not detect this signature in their experiment.

Doubling the run

The experiment continues now, with a longer run ongoing until 2028. By then, the detector will have collected a record-breaking 1,000 days of data. Longer runs give researchers a better chance of catching rare events.

The detector will hunt not only for more solar neutrino or WIMP interactions but also other physics that may fall outside the Standard Model of particle physics said to describe most of the environment around us.

Gaitskell emphasized that the role of science is to keep pushing forward even when "negative" results arise.

"One thing I've learned is, don't ever assume that nature does things in the way that you think it should, exactly," said Gaitskell, who has been studying dark matter for more than four decades.

"There are plenty of elegant [solutions] that you would say, 'That's so beautiful. It has to be true.' And we tested them … and it turned out, nature ignored it and nature did not want to go down that particular route."

Editor's note: This article was updated on Dec. 10 at 5 p.m. ET with a correction. The detector's next run won't begin in 2028, but rather end then, after a cumulative 1,000 days of data have been collected.

A new study suggests that a NASA telescope may have made the first-ever observation of elusive dark matter, the invisible and mysterious substance that makes up most of the matter in the universe. However, scientists, including the study author, caution that more research is needed to understand the finding.

NASA's Fermi Gamma-ray Space Telescope, which studies high-energy wavelengths of light known as gamma-rays, spotted emissions in the center of the Milky Way that may be associated with particles linked with dark matter, according to the study, published Tuesday (Nov. 25) in the Journal of Cosmology and Astroparticle Physics.

"If this is correct, to the extent of my knowledge, it would mark the first time humanity has 'seen' dark matter," Tomonori Totani, an astronomy professor at the University of Tokyo and the sole author of the study, said in a statement.

But the study cautions that independent confirmation of this signal must be obtained — not only from the Milky Way but also "from other objects or regions" with similar properties. Similarly, theoretical physicist Sean Tulin, an assistant professor of physics and astronomy at York University in Toronto, told Live Science he would like an independent analysis of the work because it's not the first time such claims have been made using the Fermi telescope.

A prominent example is the "galactic center excess," a source of unexplained gamma-ray light discovered with Fermi data in 2009. After nearly two decades of further research, scientists continue to debate whether the excess is the result of dark matter or more conventional astronomical sources, such as fast-spinning stars known as pulsars.

WIMPs in the cosmos

Dark matter is a nonluminous substance believed to make up most of the matter in the universe. So far, it has been traced only through its gravitational effects on other objects. For example, in a seminal 1933 paper, astronomer Fritz Zwicky stated that faraway galaxies were moving around each other faster than predicted based on the visible matter that could be seen with telescopes. The gravitational pull of dark matter was pegged as the likely reason.

There have been several theories about what dark matter includes, but most astronomers today suggest it is made of subatomic particles. Totani's study centers on a popular particle suggestion, the weakly interacting massive particle (WIMP).

WIMPs fall outside the widely used Standard Model of particle physics, which successfully shows (for the most part) how the building blocks of matter interact with each other. But the model does not account for the force of gravity or the existence of dark matter, according to CERN.

WIMPs are heavier than protons, according to the statement, and WIMPs hardly interact with other types of matter. But when two WIMPs crash into each other, these particles would be destroyed and energetically unleash other particles during the collision, including photons of gamma-rays.

Dark matter, or no?

To search for the gamma-rays associated with WIMP collisions, many studies have focused on clusters of dark matter, such as the center of our Milky Way galaxy. Data obtained from 15 years of observations with the Fermi telescope showed gamma-rays "in a halo-like structure toward the center of the Milky Way galaxy" that "matches the shape expected from the dark matter halo."

These gamma-rays were extremely energetic, with a photon energy of 20 gigaelectron volts (20 billion electron volts). According to the statement, this energy "matches the emission predicted from the annihilation of hypothetical WIMPs," as well as the frequency of WIMP annihilation.

However, Tulin pointed out that the signal shows up only when you remove the background of "all sources of energetic photons coming from the Milky Way," including from its center and its disk. Some background energy is also present from "Fermi bubbles" — two huge zones of gas and cosmic rays that loom over the Milky Way.

All studies looking at energy sources from the Milky Way need to model that background noise and then subtract that to "reveal the underlying signal," Tulin said. "What you infer for the signal depends very carefully on what you subtracted off of the background. … There's a risk of being tricked if you subtract something off incorrectly."

Aside from questions about the background, the signal could depend on the type of dark matter particle being discussed, Tulin said. "What that means is, what is the model for that dark matter particle?" he said. "What is its mass? What are its fundamental properties? What are its different interactions?"

However, the model of annihilation for a standard WIMP is "perfectly reasonable" with the signal Totani observed, Tulin said, with the assumptions that the study is observing WIMPs under the model we understand and the background is subtracted correctly.

Tulin (who had access to a study preprint when speaking with Live Science) added that despite his cautions, the findings "would be a remarkable thing if it was due to dark matter … not just for the future of the astronomical observations, but this type of dark matter particle could be tested and discovered in all sorts of different experiments, like underground labs and in colliders."

That said, "no one is really staking their house on this being the one time that it turned out to be correct," Tulin said of the new study. "We've seen a lot of anomalies come. A lot of anomalies go. Some anomalies have stuck with us, and still require further exploration."

Dark matter near the center of our galaxy is "flattened," not round as previously thought, new simulations reveal. The discovery may point to the origin of a mysterious high-energy glow that has puzzled astronomers for more than a decade, although more research is needed to rule out other theories.

"When the Fermi space telescope pointed to the galactic center, it measured too many gamma rays," Moorits Mihkel Muru, a researcher at the Leibniz Institute for Astrophysics Potsdam in Germany and the University of Tartu in Estonia, told Live Science via email. "Different theories compete to explain what could be producing that excess, but nobody has the definitive answer yet."

Early on, scientists proposed that the glow might come from dark matter particles colliding and annihilating each other. However, the signal's flattened shape didn't match the spherical halos assumed in most dark matter models. That discrepancy led many scientists to favor an alternative explanation involving millisecond pulsars — ancient, fast-spinning neutron stars that emit gamma-rays.

Now, a study published Oct. 16 in the journal Physical Review Letters and led by Muru challenges the long-standing assumption about the shape of dark matter. Using advanced simulations of the Milky Way, Muru and his colleagues found that dark matter near the galactic center is not perfectly round, but flattened — just like the observed gamma-ray signal.

A persistent cosmic puzzle

Gamma-rays are the most energetic form of light. They are often produced in the universe's most extreme environments, such as violent stellar explosions and matter swirling around black holes. Yet even after accounting for known sources, astronomers have consistently found an unexplained glow coming from the Milky Way's core.

One proposed explanation is that the radiation originates from dark matter — the invisible substance that makes up most of the universe's mass. Some models suggest that dark matter particles can occasionally smash together, converting part of their mass into bursts of gamma-rays.

"As there are no direct measurements of dark matter, we don't know a lot about it," Muru said. "One theory is that dark matter particles can interact with each other and annihilate. When two particles collide, they release energy as high-energy radiation."

But this theory fell out of favor when the flattened, disk-like shape of the gamma rays failed to match up with the hypothesized shape of dark matter haloes — which are thought to be spherical.

Rethinking the shape of dark matter

Muru and his colleagues set out to revisit the basic assumption that dark matter in the inner galaxy must be spherical. Using high-resolution computer simulations known as the HESTIA suite, which re-creates Milky Way-like galaxies within a realistic cosmic environment, the team studied how dark matter behaves near the galactic center.

They found that past mergers and gravitational interactions can distort the distribution of dark matter, flattening it into an oval or box-like shape — much like the bulge of stars seen in the middle of our galaxy.

"Our most important result was showing that a reason why the dark matter interpretation was disfavored came from a simple assumption," Muru said. "We found that dark matter near the center is not spherical — it's flattened. This brings us a step closer to revealing what dark matter really is, using clues coming from the heart of our galaxy."

This revised picture means that the pattern of gamma-rays expected from dark matter annihilation could naturally look very similar to what astronomers observe. In other words, the dark matter explanation might have been underestimated simply because scientists were using the wrong shape.

What comes next

Although the new findings strengthen the case for dark matter as the origin of the gamma-ray signal, they don't close the debate. To distinguish between dark matter and pulsars, astronomers need sharper observations.

"A clear indication for the stellar explanation would be the discovery of enough pulsars to account for the gamma-ray glow," Muru said. "New telescopes with higher resolution are already being built, which could help settle this question."

If upcoming instruments, such as the ​​Square Kilometre Array (SKA) and the Cherenkov Telescope Array (CTA), reveal many tiny, point-like sources at the galactic center, it would favor the pulsar explanation. If, instead, the radiation remains smooth and diffuse, the dark matter scenario would gain support.

"A 'smoking gun' for dark matter would be a signal that matches theoretical predictions precisely," Muru noted, adding that such a confirmation will require both improved modeling and better telescopes. "Even before the next generation of observations, our models and predictions are steadily improving. One future outlook is to find other places to test our theories, such as the central regions of nearby dwarf galaxies."

The mystery of the gamma-ray excess has endured for more than 10 years, with each new study adding a piece to the puzzle. Whether the glow comes from dark matter, pulsars or something entirely unexpected, Muru's results highlight how the galaxy's structure itself may hold vital clues. By reshaping our understanding of the Milky Way's dark core, scientists are inching closer to answering one of the most profound questions in modern astrophysics — what dark matter really is.

Astronomers have discovered a surprisingly small "dark object" lurking within a distant ring of warped light. The record-breaking find could help shed light on the mysterious identity of dark matter, which would have major implications for the field of cosmology.

The hidden object, likely a clump of invisible dark matter, was spotted within B1938+666 — an "Einstein ring" located around 10 billion light-years from Earth. This luminous halo (which appears dark in the black-and-white images) is made up of light from a distant galaxy that has been bent around a closer foreground galaxy (the dark dot at the center of the ring). This is an effect of gravitational lensing, a phenomenon that was first proposed by Albert Einstein's theory of general relativity in 1915.

Gravitational lensing not only warps light but also significantly magnifies it. When the lensing object is perfectly aligned between the distant object and the observer, the light bends into a circle around the foreground object, known as an Einstein ring. However, an imperfect alignment can also create other strange shapes, such as crosses, zig-zags and question marks, and duplicate individual points of light within the same image.

B1938+666 was discovered in the 1990s. But in a pair of new studies, published Oct. 9 in the journals Nature Astronomy and Monthly Notices of the Royal Astronomical Society, researchers took a closer look at the gravitationally lensed object and found a subtle wobble within a prominent arc of radio waves in the outer ring (colored red and yellow in the image). They quickly realized this was a gravitational disturbance caused by a hidden object.

"From the first high-resolution image, we immediately observed a narrowing in the gravitational arc, which is the tell-tale sign that we were onto something," John McKean, an astronomer at the University of Groningen in the Netherlands and the University of Pretoria in South Africa, and co-author on both new studies, said in a statement. "Only another small clump of mass between us and the distant radio galaxy could cause this."

The object is around 1 million times more massive than the sun, which sounds like a lot. However, this actually makes it around 100 times smaller than the previous record-holder for the least-massive object ever detected via gravitational lensing.

The study teams uncovered this object by combining data from radio observatories located across the globe, including the Green Bank Telescope in West Virginia, the Very Long Baseline Array in New Mexico and the European Very Long Baseline Interferometry Network. This enabled the researchers to achieve the equivalent observing power of an Earth-size telescope, which helped them to detect such a subtle fluctuation in the data. But there was so much information that the researchers had to come up with a new way of sorting it.

"The data are so large and complex that we had to develop new numerical approaches to model them," Simona Vegetti, an astronomer at the Max Planck Institute for Astrophysics in Germany and co-author on both new studies, said in the statement. "This was not straightforward as it had never been done before."

While they cannot be certain, the researchers are confident that the new object is a small clump of dark matter — the invisible matter that makes up 27% of the known universe and does not interact with light. This is unsurprising, given that gravitational lensing is one of the only ways we can detect and measure dark matter, making Einstein rings and other warped objects one of our greatest weapons in unmasking its true identity.

Finding isolated dark matter clumps like this is especially useful for testing the "cold dark matter theory," which posits that dark matter can only clump together if it moves at relatively slow speeds, meaning it would give off relatively low amounts of energy, Live Science's sister site Space.com reported.

And the researchers predict that these clumps are far more common than we currently realize. "We expect every galaxy, including our own Milky Way, to be filled with dark matter clumps, but finding them and convincing the community that they exist requires a great deal of number-crunching," Vegetti said.

To date, only three other similarly small, potential dark matter clumps have been identified, the researchers wrote. However, the new methodology will make it easier to spot more clumps around existing Einstein rings, and the number of known rings is also climbing fast, thanks to the James Webb Space Telescope, which has proved to be exceptionally good at finding them.

"Having found one, the question now is whether we can find more," Devon Powell, an astronomer at the Max Planck Institute for Astrophysics and co-author on both new studies, said in the statement.

The second most distant object ever spotted by the James Webb telescope may be a 'dark star' powered by dark matter rather than nuclear fusion.

By looking at the wavelengths of light picked up by the James Webb Space Telescope (JWST), researchers have identified four dark star candidates — with one seemingly possessing a “smoking gun” helium absorption signature, the researchers reported in a study published Sept. 30 in the journal PNAS.

First hypothesized in 2007, dark stars are believed to be among some of the first stars — called Population III stars — to form after the Big Bang. According to the theory, they are made when collapsing hydrogen and helium, which on their own would form a black hole, mix with dark matter. Dark stars are thought to be extraordinarily massive and bright, reaching one million times the mass of the sun and burning one billion times as bright.

"Our initial name 'dark star' is a misnomer," study co-author Katherine Freese, a professor of physics at The University of Texas at Austin who proposed the dark star hypothesis, told Live Science. "They're neither made [entirely] of dark matter nor are they dark."

Finding dark stars could explain some of the very puzzling objects that JWST has spotted in the early universe, such as the giant supermassive black holes that formed impossibly fast, Freese said. It would also provide insights into the nature of dark matter. "It's a probe, not just a new kind of star," she said, "so these candidates are very encouraging to us."

To spot the potential dark star candidates, the team trawled through observations from the JWST Advanced Deep Extragalactic Survey (JADES). They focused on data collected by the Near InfraRed Spectrograph (NIRSpec): an instrument measuring the individual wavelengths of light coming from celestial objects to learn about their temperatures, masses and chemical fingerprints.

The researchers set various criteria in their search: the signals needed to be no younger than redshift 10 (a redward stretching of the universe’s ancient light corresponding to 500 million years after the Big Bang), could only contain hydrogen and helium, and had to be from a single object.

This led them to four dark star candidates: JADES-GS-z11-0, JADES-GS-z13-0, JADES-GS-z14-0 and JADES-GS-z14-1. JADES-GS-z14-0 is the second most distant object observed by JWST to date.

Signals from the first stars

Models of each candidate showed that all four could plausibly be dark stars, perhaps even supermassive dark stars.

The team also found hints of the “smoking gun signature” for supermassive dark stars in the JADES-GS-z14-0 wavelength data — singly ionized helium atoms absorbing light particles with a wavelength of 1640 angstroms (an angstrom is one hundred-million times smaller than a centimeter).

"No other known high redshift objects are expected to produce such an absorption feature," the authors wrote in the study, adding weight to their suggestion that JADES-GS-z14-0 is a dark star.

The team were surprised to discover, however, that the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile had detected JADES-GS-z14-0 emitting oxygen, an element only produced by nuclear fusion powered stars. "That worries me a little bit," Freese said.

The team are now running simulations to determine how much oxygen is permitted before a dark star is no longer able to form, study co-author Cosmin Ilie, a physicist at Colgate University in New York, told Live Science. "Logic tells me that there should be sort of a transition," he said.

Dark stars remain controversial and their existence is by no means accepted. "The majority of the Pop III star community actually doesn't think that dark matter burners [dark stars] can form," Daniel Whalen, a cosmologist at the University of Portsmouth in the U.K. who was not involved in the research, told Live Science.

In fact, Whalen said that a "huge issue" with this research is that it did not differentiate between dark stars and supermassive primordial stars. "That's the elephant in the room really here," he said.

Although the dark star candidates are more massive than most supermassive primordial stars, their wavelength data needs to be compared for both star types to rule out supermassive primordial stars, Whalen explained.

In response to this criticism, Ilie said that because supermassive primordial stars don't live as long as dark stars, if many suitable signatures are identified they are statistically more likely to be dark stars. That means many more observations are needed to settle this mystery.

Meanwhile, Freese said that the team is working on automating the search for dark stars in the JWST data "so we don't have to do anything except keep our eyes open."

An odd image of a distant galaxy has revealed what might be an enormous blob of dark matter hiding in plain sight.

When astronomers first looked at the new image of the galaxy HerS-3, taken by the Northern Extended Millimeter Array radio telescopes in France, they thought there was an error in the data.

"We were like, 'What the heck?'" Pierre Cox, an astronomer at the French National Center for Scientific Research, said in a statement.

The image showed what appeared to be an "Einstein cross." This rare phenomenon occurs when light from a distant galaxy or quasar (a bright galaxy with an actively-feeding black hole at its center) bends around the gravity of a massive object in front of it, so that it appears to have split into four points from the perspective of an observer. But what made this configuration so unusual was the fifth point of light glowing in its center. At first, "we thought it was a problem with the instrument," Cox said.

Because the photons of an Einstein cross curve around a central mass, scientists wouldn't normally expect to see a fifth point in the middle.

"You can't get a fifth image in the center unless something unusual is going on with the mass that's bending the light," Charles Keeton, an astronomer at Rutgers University and co-author of a new study describing the findings, said in a statement.

In the study, published Sept. 16 in The Astrophysical Journal, the researchers used computer modeling to try to figure out exactly what was going on with the weird cross. Their analysis revealed that all of the points of light originated from HerS-3, which ruled out the possibility that a closer, brighter object was getting in the way. They also ruled out a straightforward instrument malfunction by checking the image against data collected by the Large Millimeter/submillimeter Array (ALMA) in Chile.

Finally, they ran a computer simulation in which a mass of dark matter sat in front of HerS-3 — and this time, the results matched their observations.

Dark matter is notoriously difficult to image. It does not absorb, reflect or emit light, so it's functionally invisible. However, it does have gravity. A large halo of dark matter would have enough gravitational pull to bend the light of a galaxy directly behind it while leaving the galaxy itself visible (and therefore capable of being warped into an Einstein cross).

The discovery offers an exciting opportunity for scientists to learn more about how dark matter interacts with other cosmic objects. "We can study both the distant galaxy and the invisible matter that's bending its light," Cox said.

The team hopes to use these future observations to further test and refine the computational models.

Astronomers have spotted two massive galaxies locked in a cosmic tug-of-war 700 million light-years from Earth — and for the first time in such a nearby galaxy, watched as a faint stream of stars is being pulled from one into the other.

The observations, made in the galaxy cluster Abell 3667, revealed a faint, million light-year-long bridge of stars connecting its two brightest galaxies. Astronomers say the cluster is actually the result of two smaller clusters that began merging about a billion years ago, each with its own dominant central galaxy. As these giants — and their satellite galaxies — continue to merge, the bridge of stars between them offers rare insights into the clusters' history and the powerful gravitational forces at play.

"This is the first time a feature of this scale and size has been found in a local galaxy cluster," Anthony Englert, a Ph.D. candidate at Brown University in Rhode Island, who led a new paper describing the observations, said in a statement. "It was a huge surprise that we were able to image such a faint feature."

The bridge is made of intracluster light, or ICL, a diffuse glow from stars that have been stripped from their home galaxies by intense gravitational forces. Englert and his team were able to detect this dim bridge by stacking 28 hours of observations taken over several years using the Dark Energy Camera at the Cerro Tololo Inter-American Observatory in Chile.

"It was just a happy coincidence that so many people had imaged Abell 3667 over the years, and we were able to stack all of those observations together," Englert said in the statement.

At the top of the bridge lies the lenticular (disc-shaped) galaxy IC 4965, along with a small group of galaxies that are still falling into the cluster. At the bottom of it is JO171, a striking "jellyfish galaxy" named for the long tendrils of gas trailing from one side. As it merges into Abell 3667, JO171 is being stripped of gas, shutting down star formation in part of its ring-like structure, according to the statement.

Beyond its visual beauty, the light bridge also provides a valuable probe of dark matter, the invisible substance believed to make up roughly 80% of the universe's mass. Because intracluster light tends to trace the same paths as dark matter, it offers an indirect way to map its distribution, astronomers say.

"The distribution of this light should mirror the distribution of dark matter, so it provides an indirect way to 'see' the dark matter," study co-author Ian Dell'Antonio of Brown University said in the statement.

The study also highlights the kind of discoveries that are expected to soon become routine with the upcoming Vera C. Rubin Observatory, scheduled to begin full operations later this year or in early 2026. Rubin's Legacy Survey of Space and Time (LSST) will map the southern sky in unprecedented detail over a 10-year period using the world's largest digital camera, bringing to light galaxy clusters like Abell 3667.

"What we did is just a small sliver of what Rubin is going to be able to do," Englert said in the statement. "It's really going to blow the study of the ICL wide open."

This research is described in a paper published Aug. 5 in The Astrophysical Journal.

Astronomers have found what they claim is fresh evidence that Earth and our Milky Way galaxy are suspended inside a gigantic void that's skewing our observations of the cosmos.

The radical proposal, made by analyzing echoes of the Big Bang, suggests that our galaxy may be floating in a 2 billion-light-year region that's 20% less dense than average.

If the results hold up, they could help astronomers find the true age of our universe and offer a solution to one of the stickiest conundrums in cosmology — the discrepancy, known as the Hubble tension, that the distant universe expanded more slowly in the past than the nearby universe does today.

The findings would also prompt a major rewrite of existing cosmological models. The researchers shared their findings July 9 at the Royal Astronomical Society's National Astronomy Meeting in Durham, England.

Hubble trouble

Over the past decade, cosmology has been embroiled in a growing crisis as observations — first made by the Hubble Space Telescope and later by the James Webb Space Telescope — suggested that the universe is expanding at different rates depending on where astronomers look.

Currently, there are two gold-standard methods for figuring out this expansion rate, called the Hubble constant. The first involves poring over tiny fluctuations in the cosmic microwave background, an ancient relic of the universe's first light produced just 380,000 years after the Big Bang. This method enabled astronomers to infer an expansion rate of roughly 67 kilometers per second per megaparsec (km/s/Mpc), which closely matches predictions made by the standard model of cosmology.

Related: 'Our model of cosmology might be broken': New study reveals the universe is expanding too fast for physics to explain

But the second method — measuring closer distances with pulsating stars called Cepheid variables — returned a puzzlingly high value for the Hubble constant of 73.2 km/s/Mpc.

This discrepancy may not seem like much, but it's enough to completely contradict the predictions made by the standard model of cosmology. Astronomers have suggested many major and minor rewrites to this model to explain the tension, including tossing out dark energy and dark matter altogether.

But this anomaly could be specific to our cosmic backyard, the astronomers behind the new research suggest.

"A potential solution to this inconsistency is that our Galaxy is close to the centre of a large, local void," lead author Indranil Banik, an astronomer at the University of Portsmouth in the U.K., said in a statement. "It would cause matter to be pulled by gravity towards the higher density exterior of the void, leading to the void becoming emptier with time."

That would make local expansion inside the void faster than it is in denser, more distant regions of the cosmos, he added.

Filling the void

The notion that our part of the universe could be less dense than others first took shape in the 1990s, when researchers found fewer galaxies in our local universe than they expected compared with the surrounding universe.

Further research backed up these observations, indicating that our galaxy may be in the center of a region known as the local hole or KBC void, named after the initials of the study's astronomers. Nonetheless, some astronomers question whether the apparently underdense space could be filled with objects that don't emit light.

To investigate the evidence further, Banik and his colleagues collected 20 years' of data from observations of nearby baryon acoustic oscillations (BAOs) — pressure waves created during the Big Bang that froze in place and expanded alongside the universe, governing the distribution of galaxies we see today.

"These sound waves traveled for only a short while before becoming frozen in place once the universe cooled enough for neutral atoms to form," Banik explained. "They act as a standard ruler, whose angular size we can use to chart the cosmic expansion history."

According to the researchers' BAO measurements, it's 100 times more likely that we live in a cosmic void than a region of average density.

The next step for Banik and colleagues will be to compare their void model to other models to see which best fits the history of the universe's expansion. They will also need to explore tweaks to the standard model of cosmology, including throwing out the assumption that matter is evenly distributed throughout the universe.

The implications would be vast — not just for our understanding of how the universe behaves but for our own place in it. Modern astronomy has consistently revealed that our personal view of the cosmos is unexceptional. However, if we do live in the middle of a void, we could be more unique in our isolation than first thought.

What it is: The Bullet Cluster

Where it is: 3.7 billion light-years from Earth, in the constellation Carina

When it was shared: June 30, 2025

Why it's so special: Galaxy clusters act as a magnifying lens, shining light on the faintest and most distant objects — a phenomenon known as gravitational lensing. On the rarest of occasions, galaxy clusters collide, creating an even more massive lens. The James Webb Space Telescope (JWST) recently provided extremely detailed observations of such a lens, the Bullet Cluster.

Located about 3.7 billion light-years from Earth in the constellation Carina, the Bullet Cluster is the aftermath of the collision between two galaxy clusters that is estimated to have begun approximately 150 million years ago. Each of the two galaxy clusters can be distinguished within the blue regions, yet they are bound by gravity and together form a single entity — the Bullet Cluster.

While gravitational lensing brings distant, faint objects into light, the extent of lensing can reveal the mass distribution within the massive foreground galaxy cluster. Mysterious dark matter makes up a huge chunk of galaxy clusters, but is difficult to spot because it does not reflect, absorb or emit light. So, astronomers sometimes study light from stars that are within the galaxy cluster but are not part of any galaxies. These stars are called intracluster stars and are floating because they are stripped from their galaxies during collisions. By analyzing the light from these stars, researchers can trace the distribution of dark matter, as these stars are gravitationally bound to the cluster's dark matter.

Related: James Webb telescope discovers tentacled 'jellyfish' galaxy swimming through deep space

The latest data from JWST, combined with data from the Chandra X-ray Observatory, allowed astronomers to create an accurate map of mass — both visible and dark matter — within the Bullet Cluster. The light from intracluster stars pinned down the location of invisible matter, and the X-rays confirmed the location of hot gas. Based on these observations, astronomers could "replay" the collision. This revealed that hot gas (in bright pink) was pulled out of the galaxy clusters and left behind in the central region, while the dark matter (in blue) associated with individual galaxy clusters stayed intact and was not dragged away.

This stunning image, a composite of JWST's near-infrared data and Chandra's X-ray data, reveals clumps and stretched-out lines of mass that were previously unknown. These newfound structures could be signatures of a chaotic history, suggesting that the Bullet Cluster may have suffered several collisions over billions of years. The larger cluster, on the left side, might have undergone separate interactions before and after colliding with the smaller cluster on the right.

This brilliant image covers only a portion of the collision's aftermath. In the future, the wide-area near-infrared images taken with NASA's Nancy Grace Roman Space Telescope could provide a complete picture of the Bullet Cluster, both by unveiling spectacular photos and unraveling its mysteries.

For more sublime space images, check out our Space Photo of the Week archives.

A gigantic array of radio dishes proposed for the Nevada desert could advance our understanding of physics and help us decode cosmic radio signals. Now, scientists have outlined how it would work.

Beginning in the 1950s, radio astronomy has opened up a powerful view into the inner workings of the universe, revealing everything from how stars form to incredible images of our galaxy's gigantic black hole. Now, astronomers are building a gigantic array of radio dishes, called the Deep Synoptic Array 2000 (DSA-2000). The array consists of 2,000 radio dishes, each 16 feet (5 meters) across, laid out in a radio-quiet part of the Nevada desert.

Now, an international team of astronomers has demonstrated how DSA-2000 will be a premier instrument for revealing some of the most hidden corners, particles and processes in the cosmos.

Because DSA-2000 will have both a wide field of view and a high resolution, it will be like the world's ultimate digital camera but at radio frequencies, the team explained in a paper uploaded to the preprint database arXiv in May. These capabilities will allow the DSA-2000 to detect a wide variety of phenomena that are not possible with our current radio telescopes.

And there are a whole lot of unexplored radio transmissions in the universe. For example, astronomers think the vast majority of the mass of every galaxy comes in the form of dark matter, an invisible entity that has so far escaped direct detection.

One potential candidate for dark matter is called the axion, a hypothetical particle trillions of times lighter than the lightest known particles. Axions can collect around dense objects like neutron stars, and under the influence of extremely strong magnetic fields (which neutron stars have in spades), they can convert to photons with just the right frequency range that DSA-2000 could pick up those signals.

Related: 'Staggering' first images from Vera C. Rubin Observatory show 10 million galaxies — and billions more are on the way

Another candidate for dark matter is called the dark photon, which is like our normal, familiar photons (light particles) but … dark. Dark photons can also collect around neutron stars, where they can get whipped up into a frenzy due to the star's extreme rotation. In a process called superradiance, the dark photons get boosted to extremely high energies, where they start to resonate with regular photons, giving off blasts of signals that could be directly detected by DSA-2000.

This means that DSA-2000 could potentially offer our first direct glimpse of a new form of matter in the universe. But that's not all.

In 2023, astronomers with the NANOGrav experiment announced the detection of gravitational waves through pulsar timing arrays. DSA-2000 could take that one step further by precisely measuring the rotation rates of approximately 3,000 pulsars — rapidly spinning neutron stars that pulsate in regular intervals. This would allow the new instrument to find any subtle variations in the spins of pulsars, such as those due to unseen orbiting companions, like black holes or small clumps of dark matter.

Lastly, DSA-2000 could detect tens of thousands of fast radio bursts (FRBs) — tremendous explosions that manifest as blips and bloops in the radio spectrum. This unprecedented number of detections would allow scientists to build a comprehensive survey of the nearby universe, which would aid our understanding of everything from dark energy to the nature of ghostly particles called neutrinos.

The universe is trying to whisper its secrets to us. All the answers are there, if we listen carefully enough.

Editor's note: This article was updated at 10:30 a.m. ET on June 9 to correct an error. The array is planned for the Nevada desert, not the Utah desert, as was previously written.

The Andromeda galaxy's spiralling stars are played as musical notes in a new NASA observatory video, creating a cosmic crescendo that's out of this world.

The sonification video, released by NASA's Chandra X-ray Observatory, combines observations of the Andromeda galaxy collected by some of the world's most powerful telescopes, according to a NASA statement. Chandra also released a spectacular composite image of the galaxy, which is the closest spiral galaxy to our own Milky Way.

Researchers created the composite image by stacking photos taken in different light wavelengths, merging radio, infrared, optical, ultraviolet and X-ray data. The researchers then converted those images to sound by assigning a separate range of notes to each of these wavelengths. In the video, a line passes across the lights, playing each assigned note like keys on a piano.

"Musical notes ring out when the line encounters light," a representative for NASA wrote in the statement. "The lower the wavelength energy, the lower the pitches of the notes. The brighter the source, the louder the volume."

NASA described the composite image as a tribute to pioneering astronomer Vera Rubin, who studied Andromeda. The tribute comes days after a new observatory named after Rubin released its first images. The Vera C. Rubin Observatory features the world's largest digital camera and will spend the next decade creating a time-lapse movie of the universe.

Related: 6 incredible objects hidden in Vera C. Rubin Observatory's mind-boggling first image

Andromeda, or Messier 31 (M31), is located around 2.5 million light-years from the Milky Way. Studying the galaxy has led to many scientific discoveries. For example, Rubin and her colleagues' observations of Andromeda led them to conclude that there must be an unseen matter influencing how its spiral arms rotate, according to the statement. The research was pivotal in furthering scientists' understanding of dark matter, an enigmatic non-luminous substance that shapes the universe.

Researchers created the new image and soundscape of Andromeda by combining different data collected over many years. For example, the X-ray image comes from data collected by Chandra and the European Space Agency's X-ray Multi-Mirror Mission (XMM-Newton). Researchers used this data to identify high-energy radiation around the supermassive black hole at the heart of Andromeda, according to the statement.

The images and sounds aren't just for fun. They are another way of examining Andromeda, and therefore a learning opportunity. Andromeda offers a view of a spiral galaxy that we can’t get from the Milky Way, given we're inside it, and so studying Andromeda furthers researchers' understanding of our own spiral galaxy, according to the statement.

"This collection helps astronomers understand the evolution of the Milky Way, our own spiral galaxy, and provides a fascinating insight into astronomical data gathering and presentation," the NASA representative wrote.

The universe's invisible dark matter might swirl into spinning clumps laced with countless tiny vortices, new theoretical work suggests.

The findings, published May 30 in the journal Physical Review D, offer a fresh perspective on the strange behavior of "ultralight" dark matter — a hypothetical substance made of extremely light elementary particles.

In the new study, physicists explored what happens when a dark matter halo rotates — a natural expectation for real galaxies, which typically spin as they evolve. Based on their theoretical modeling and detailed simulations, the authors found that this exotic material could behave like a superfluid, forming stable, rotating cores threaded with vortex lattices much like those seen in laboratory experiments.

A special kind of dark matter

Unlike the standard view of dark matter as a cloud of heavy, sluggish particles with no internal structure, the new research focuses on dark matter made of particles lighter than a millionth of an electron's mass. These particles may not float passively in space; if they interact slightly with one another through a repulsive force, they can behave more like a quantum fluid.

That fluid-like behavior allows the formation of "solitons" — compact, coherent structures where gravity's pull inward is balanced by an outward pressure from self-interactions.

"Solitons are classical solutions of the equations of motion," Philippe Brax, a theoretical physicist at Université Paris-Saclay and co-author of the study, told Live Science. "They correspond to hydrostatic equilibria where the attractive gravitational force is balanced by the repulsive particle self-interaction, somewhat like the Sun, which is also in hydrostatic equilibrium."

These solitons could range from the size of stars to entire galaxies, depending on the unknown mass of the dark matter particle. In larger cases, they could help explain why the centers of galaxies appear less densely packed with dark matter than predicted — a long-standing issue in cosmology.

From spinning clouds to vortex lattices

The researchers simulated what happens when clouds of this unusual dark matter rotate. The result was surprising: Instead of spinning smoothly like a hurricane or a solid sphere, the solitons developed an internal lattice of microscopic vortices.

"When the initial conditions are such that the dark matter cloud rotates, the end result is a rotating soliton at the center of the collapsed halo," said study co-author Patrick Valageas, also of the Université Paris-Saclay. "This soliton shows an oblate shape aligned with the initial rotation axis, and displays a solid-body rotation supported by quantized vortices."

These vortices aren't like swirling winds or whirlpools in water. Rather, they resemble the quantized vortex lines that appear in superfluids like liquid helium, where the fluid rotates not as a whole but through an array of discrete spinning threads. At the center of each vortex, the dark matter density drops to zero, and together, the vortices align into a regular, lattice-like pattern.

"Our simulations show that these vortex lines are aligned with the total angular momentum and follow circular orbits inside the soliton," Valageas said. "The rotation is not like a smooth wind but more like a bundle of microscopic tornadoes arranged in a crystal pattern."

One intriguing idea the researchers raised is whether these tiny vortex structures have implications on much larger scales. In particular, they speculated that some vortex lines might extend beyond a single halo, connecting galaxies through the vast filaments of the cosmic web — the gigantic tendrils of dark matter that shape the universe's large-scale structure.

"At this stage, the idea that some of these vortex lines could join different halos through the filaments of the cosmic web is a hypothesis," Brax noted. If true, it could mean that quantum effects in dark matter subtly influence how galaxies align and move within these colossal threads.

Detecting such vortex structures would be challenging. Because dark matter doesn't emit or absorb light, scientists can only infer its presence from its gravitational influence on visible matter like stars and gas.

Still, there may be ways to glimpse their effects. "These vortices are associated with troughs in the dark matter density," Brax said. "As such, they imprint characteristic features in the gravitational potential, which may influence the orbits of stars or gas clouds in galaxies like the Milky Way."

In more speculative scenarios, if dark matter interacts even weakly with ordinary matter or light, the vortices might leave more direct fingerprints — but for now, that remains an open question.

The team plans to investigate whether the predicted vortex lattices can be detected through astronomical observations and whether they truly connect to the cosmic filaments that stretch across space.

For now, these ghostly whirlpools remain invisible — but as theory and technology advance, scientists may find that the cosmos is not just filled with unseen matter but woven with patterns of spinning quantum threads.

Update: The first image reveal from the groundbreaking Vera C. Rubin Observatory will stream live in less than an hour! You can watch the live debut right here at 11 a.m. EDT today (Monday, June. 23) or on the Observatory's YouTube page.

The Observatory has already offered a stunning sneak peak of the new images this morning, sharing three images of distant galaxies and nebulas. Check them out at the link above to get ready for the full debut, streaming below.

How to tune in

If you want to watch from home, a news conference will be streaming on YouTube in English and Spanish at 11:00 a.m. EDT today (Monday, June 23). The link to watch is posted on the observatory's website, and is also embedded above.

If you'd prefer to bask in the awe of the cosmos with friends, you may be able to attend a watch party near you — or even host one of your own. Groups will gather across the globe in planetariums and universities to admire the highly detailed images and videos as they are released. The observatory has shared links to a map of all registered watch parties, as well as a link to sign up to become a host.

During the news conference, the observatory team will introduce the Rubin Observatory before showcasing the new images and discussing their significance. Watch parties may also hear from local scientists and special guests. Be sure to check out the details of a watch party before you attend to learn about any extra programming.

The Rubin Observatory

The observatory, perched high on a mountain in the Chilean Andes, will peer at interstellar comets and dangerous asteroids, as well as larger objects, like twisting galaxies and exploding supernovas.

Related: 'People thought this couldn't be done': Scientists observe light of 'cosmic dawn' with a telescope on Earth for the first time ever

Inside Rubin lies the world's largest digital camera and six of the largest optical filters ever produced. Together, they allow researchers to observe different facets of the universe in many wavelengths of light and remarkably high detail.

The camera will take a new high-resolution photo of the sky around every 40 seconds. The images will then be transmitted via fiber optic cables to a supercomputer in California, which will analyze the photos. When stitched together, the images can act as a time-lapse video of space, one that is planned to span 10 years.

Using its groundbreaking instruments, the observatory is expected to contribute to current understanding of widely debated phenomena, including dark energy and dark matter — two components that are thought to make up a vast majority of the universe, but remain poorly understood.

The new images could be the first of many that vastly improve our understanding of the cosmos. Whether you join a watch party or tune in from the comfort of your couch, these photos are not to be missed.

Editor's note: This article was updated Monday (June 23) to include a link to sneak peak images from the Observatory

Roughly half of all the regular matter in the universe has been unaccounted for — until now.

In a new study, researchers claim that, using short, extragalactic flashes called fast radio bursts (FRBs), they have accounted for all the baryonic matter — the "normal" matter that makes up stars, planets, and other objects that interact with light — that we expect to find in the universe. Much of the "missing" matter is spread thinly through the space between galaxies, according to the study, which was published June 16 in the journal Nature Astronomy.

Baryonic matter, which is composed of particles like protons and neutrons, makes up just 5% of the universe. Another 27% is invisible dark matter, and the rest is mysterious dark energy that drives the universe's accelerating expansion. But scientists have been able to observe only about half as much baryonic matter as they expect to have been produced during the Big Bang.

To account for the remaining matter, the researchers looked to 69 FRBs to light up the intergalactic space that lies between the bursts and Earth. No one knows what causes FRBs, but most of the powerful, millisecond-long radio flashes originate outside the Milky Way.

"The FRBs shine through the fog of the intergalactic medium, and by precisely measuring how the light slows down, we can weigh that fog, even when it's too faint to see," study co-author Liam Connor, an astronomer at Harvard University, said in a statement.

Related: Earth's upper atmosphere could hold a missing piece of the universe, new study hints

Using this technique, Connor and his colleagues found that about 76% of regular matter in the universe lies in the intergalactic medium, the hot gas that fills the space between galaxies. Another 15% or so can be found in galaxy halos — the hot, spherical regions at the edges of galaxies. The remaining baryonic matter makes up the stars, planets and cold gases inside galaxies themselves, the team proposed.

"It's like we're seeing the shadow of all the baryons, with FRBs as the backlight," study co-author Vikram Ravi, an astronomer at Caltech, said in the statement. "If you see a person in front of you, you can find out a lot about them. But if you just see their shadow, you still know that they're there and roughly how big they are."

The findings observationally account for all baryonic matter in the universe for the first time, pinpointing not just whether this matter exists but also where it is concentrated in the universe.

"I would say that the missing baryons problem is essentially solved," Nicolás Tejos, an astronomer at the Pontifical Catholic University of Valparaíso who was not involved in the study, told Science magazine. "Thanks to FRBs, we have now been able to close this baryon budget."

In future studies, the team hopes to leverage the Deep Synoptic Array-2000, a proposed network of 2,000 radio telescopes that will scan the entire sky over five years, to pinpoint up to 10,000 new FRBs per year and investigate the universe's baryonic matter in even more detail.

In the face of eye-watering costs, long construction times and the Trump administration's slashing of federal science funding, physicists have proposed a cheaper alternative to the next-generation of particle supercolliders — peering into black holes.

Scientists initially hoped that the elusive particles that make up dark matter would be spat out by high-energy proton collisions inside CERN's Large Hadron Collider (LHC), yet so far no such detection has been made.

Finding dark matter, therefore, could mean waiting decades until new, higher energy, supercolliders are built.

Or perhaps not, according to one group of researchers. Publishing their findings June 3 in the journal Physical Review Letters, they suggest that the answers we're looking for could be in violent collisions inside the fast-moving accretion disks that surround enormous black holes.

"One of the great hopes for particle colliders like the Large Hadron Collider is that it will generate dark matter particles, but we haven't seen any evidence yet," study co-author Joseph Silk, an astrophysics professor at Johns Hopkins University and the University of Oxford, U.K. said in a statement. "That's why there are discussions underway to build a much more powerful version, a next-generation supercollider. But as we invest $30 billion and wait 40 years to build this supercollider — nature may provide a glimpse of the future in super massive black holes."

Particle colliders work by smashing particles into each other at near-light-speeds, creating interactions from which the most fundamental elements of the universe briefly emerge as high-energy debris. It's from these collisions that the LHC discovered the Higg's Boson in 2012, the elusive particle that gives all others their mass.

Related: World's largest atom smasher turned lead into gold — and then destroyed it in an instant

But despite this discovery and many others (alongside key contributions to the development of the internet, computing and some cancer therapies) the LHC has yet to produce dark matter, possibly because it is incapable of reaching the energies required to produce its particles.

One of the universe's most mysterious components, dark matter makes up roughly 27% of our cosmos's missing content. But it doesn't interact with light, so it has yet to be directly detected. This means that despite countless observations of the ways it shapes our universe, scientists are still unsure of where dark matter comes from, or even what it is.

Seeking a new source of dark matter particles, the researchers behind the new study looked to black holes. Observations by space telescopes have revealed that rapidly spinning black holes can launch massive jets of plasma from the accretion disks of hot matter that surround them.

And according to the researchers' calculations, these jets could be far more powerful than first thought — enabling particles to collide at similar energy levels as those projected for future supercolliders.

"Some particles from these collisions go down the throat of the black hole and disappear forever," Silk said. "But because of their energy and momentum, some also come out, and it's those that come out which are accelerated to unprecedentedly high energies."

Silk's team calculated that the energy produced by black hole jets could be "as powerful as you get from a supercollider, or more," adding that "it's very hard to say what the limit is."

To detect the particles zipping from black hole collisions, the researchers propose tracking them with observatories designed to study supernovae, such as the South Pole's IceCube Neutrino Observatory or the Kilometer Cube Neutrino Telescope.

"If supermassive black holes can generate these particles by high-energy proton collisions, then we might get a signal on Earth, some really high-energy particle passing rapidly through our detectors," Silk said. "That would be the evidence for a novel particle collider within the most mysterious objects in the universe, attaining energies that would be unattainable in any terrestrial accelerator. We'd see something with a strange signature that conceivably provides evidence for dark matter, which is a bit more of a leap but it's possible."

A mysterious second flavor of hydrogen atoms — one that doesn't interact with light — may exist, a new theoretical study proposes, and it could account for much of the universe's missing matter while also explaining a long-standing mystery in particle physics.

The mystery, known as the neutron lifetime puzzle, revolves around two experimental methods whose results disagree on the average lifetime of free neutrons — those not bound within atomic nuclei — before they decay to produce three other particles: protons, electrons and neutrinos.

"There were two kinds of experiments for measuring the neutron lifetime," Eugene Oks, a physicist at Auburn University and sole author of the new study published in the journal Nuclear Physics B, told Live Science in an email.

The two methods are called beam and bottle. In beam experiments, scientists count protons left behind immediately after neutrons decay. Using the other approach, in bottle experiments, ultra-cold neutrons are trapped and left to decay, and the remaining neutrons are counted after the experimental run is over — typically lasting between 100 and 1000 seconds, with many such runs performed under varying conditions like trap material, storage time, and temperature to improve accuracy and control for systematic errors.

These two methods yield results that differ by about 10 seconds: beam experiments measure a neutron lifetime of 888 seconds, whereas bottle experiments report 878 seconds — a discrepancy well beyond experimental uncertainty. "This was the puzzle," said Oks.

Solving the puzzle… with invisible atoms

In his study, Oks proposes that the discrepancy in lifetimes arises because a neutron sometimes decays not into three particles, but just two: a hydrogen atom and a neutrino. Since the hydrogen atom is electrically neutral, it can pass through detectors unnoticed, giving the false impression that fewer decays have occurred than expected.

Although this two-body decay mode had been proposed theoretically in the past, it was believed to be extremely rare — occurring in only about 4 out of every million decays. Oks argues that this estimate is dramatically off because previous calculations didn't consider a more exotic possibility: that most of these two-body decays produce a second, unrecognized flavor of hydrogen atom. And unlike ordinary hydrogen, these atoms don’t interact with light.

"They do not emit or absorb electromagnetic radiation, they remain dark," Oks explained. That would make them undetectable using traditional instruments, which rely on light to find and study atoms.

Related: How many atoms are in the observable universe?

What distinguishes this second flavor? Most importantly, the electron in this type of hydrogen would be far more likely to be found close to the central proton than in ordinary atoms, and would be completely immune to the electromagnetic forces that make regular atoms visible.

The invisible hydrogen would be hard to detect. "The probability of finding the atomic electron in the close proximity to the proton is several orders of magnitude greater than for ordinary hydrogen atoms," Oks added.

This strange atomic behavior comes from a peculiar solution to the Dirac equation — the core equation in quantum physics that describes how electrons behave. Normally, these solutions are considered unphysical, but Oks argues that once the fact that protons have a finite size is taken into account, these unusual solutions start to make sense and describe well-defined particles.

By considering a second flavor of hydrogen, Oks calculates that the rate of two-body decays could be enhanced by a factor of about 3,000. This would raise their frequency to around 1% of all neutron decays — enough to explain the gap between beam and bottle experiments. "The enhancement of the two-body decay by a factor of about 3000 provided the complete quantitative resolution of the neutron lifetime puzzle," he said.

That's not all. Invisible hydrogen atoms might also solve another cosmic mystery: the identity of dark matter, the unseen material that’s thought to make up most of the matter in the universe today.

In a 2020 study, Oks showed that if these invisible atoms were abundant in the early universe, they could explain an unexpected dip in ancient hydrogen radio signals observed by astronomers. Since then, he has argued that these atoms may be the dominant form of baryonic dark matter — matter made from known particles like protons and neutrons, but in a form that’s hard to detect.

"The status of the second flavor of hydrogen atoms as baryonic dark matter is favored by the Occam’s razor principle," said Oks, referring to the idea that the simplest explanation is often best. "The second flavor of hydrogen atoms, being based on the standard quantum mechanics, does not go beyond the Standard Model of particle physics."

In other words, no exotic new particles or material are needed to explain dark matter — just a new interpretation of atoms that we already thought we understood.

Testing the new theory

Oks is now collaborating with experimentalists to test his theory. At the Los Alamos National Laboratory in New Mexico, a team is preparing an experiment based on two key ideas. First, both flavors of hydrogen can be excited using an electron beam. Second, once excited, ordinary hydrogen atoms can be stripped away using a laser or electric field — leaving behind only the invisible ones. A similar experiment is also being prepared in Germany at the Forschungszentrum Jülich, a national research institute near Garching.

The stakes for these tests are high. "If successful, the experiment could yield results this year," said Oks. "The success would be a very significant breakthrough both in particle physics and in dark matter research."

In the future, Oks plans to explore whether other atomic systems might also have two flavors, potentially opening the door to even more surprising discoveries. And if confirmed, such findings could also reshape our understanding of cosmic history.

"The precise value of the neutron lifetime is pivotal for calculating the amount of hydrogen, helium and other light elements that were formed in the first few minutes of the universe's life," Oks said. So his proposal doesn't just solve a long-standing puzzle — it could rewrite the earliest chapters of cosmic evolution.

Astronomers have stumbled upon yet another ghostly galaxy that appears to be devoid of dark matter.

Dark matter, the invisible substance astronomers believe dominates the universe, provides the gravitational scaffolding for galaxies to assemble and grow. Discovering a galaxy without dark matter is indeed perplexing, like finding a shadow without a source.

Yet, over the past decade, several such sightings have been reported — all of them so-called "ultradiffuse galaxies," which are about the size of our own Milky Way but remarkably sparse in stars.

The latest member of this puzzling collection, known as FCC 224, resides on the fringes of the Fornax Cluster, a collection of galaxies that lies roughly 65 million light-years from Earth.

Related: Scientists may have finally found where the 'missing half' of the universe's matter is hiding

First spotted in 2024, FCC 224 is a dwarf galaxy that boasts a dozen luminous, tightly bound clusters of stars — an unusually rich population for its size, typically seen in larger, dark-matter rich galaxies — yet appears to lack the mysterious substance. It also occupies a distinctly different cosmic neighborhood than other galaxies that are deficient in dark matter, suggesting such objects might not be isolated flukes but rather represent a more common, previously unrecognized class of dwarf galaxies, according to two complementary papers published last month.

"No existing galaxy formation model within our standard cosmological paradigm can currently explain how this galaxy came to be," Maria Buzzo, a doctoral candidate in astrophysics at the Swinburne University of Technology in Australia who led one of the new studies, said in a statement.

Using data from the Keck Observatory in Hawaii, Buzzo and her team tracked the movement of a dozen star clusters within FCC 224. These measurements revealed a slow speed among the clusters, a key indicator that the galaxy lacks the strong gravitational pull expected from dark matter, the new study reports. No known scenario can fully explain FCC 224's properties, the researchers say.

Another team, led by astronomer Yimeng Tang at the University of California, Santa Cruz, compared FCC 224's properties to other galaxies that seemingly lack dark matter, focusing on two ghostly objects within the NGC 1052 group about 65 million light-years away in the constellation Cetus.

Tang and his colleagues propose that FCC 224, like those NGC 1052 dwarf galaxies, formed from a high-velocity collision of gas-rich galaxies. In such an event, the gas separates from the dark matter, and subsequent star formation in the expelled gas forms one or more dark-matter-free galaxies.

Previous research found that the two galaxies in the NGC 1052 group, DF2 and DF4, belong to a trail of seven to 11 dark-matter-deficient galaxies that formed in the same ancient collision. FCC 224 likely has a twin galaxy, too, Tang and his team suggest in their study.

One candidate is the nearby galaxy FCC 240, which appears to have the same size, shape and orientation as FCC 224. If forthcoming observations confirm the shared properties, it would provide crucial evidence supporting the collision scenario for the formation of FCC 224, the researchers say.

Alternatively, FCC 224 could be the result of a chaotic, high-energy environment where intense star formation from overmassive star clusters expelled dark matter from the galaxy, the team suggests.

"FCC 224 serves as a crucial data point in our effort to identify and study other dark-matter-deficient galaxies," Buzzo said in the statement. "By expanding the sample size, we can refine our understanding of these rare galaxies and of the role of dark matter in dwarf galaxy formation."

Originally posted on Space.com.

The universe's missing matter may have finally been found.

Astronomers think regular matter — that is, the stuff that isn't dark matter — makes up about 15% of the universe's total mass. However, for years, researchers have run into a problem when trying to quantify it: They haven't been able to find about half of that "normal" matter in the stars, galaxies and other space structures we can see.

But now, a large, international team of researchers has found that the diffuse hydrogen gas surrounding most galaxies is significantly more extensive than scientists previously thought — so extensive, in fact, that it could account for most of the universe's missing matter, the team says.

"The measurements are certainly consistent with finding all of the [missing] gas," study co-author Simone Ferraro, an astronomer at the University of California, Berkeley, said in a statement. The study is currently available on the preprint server arXiv and is undergoing peer review for publication in the journal Physical Review Letters.

The hunt for the missing matter

For their investigation, the researchers used data from the Dark Energy Spectroscopic Instrument (DESI) at Kitt Peak National Observatory in Arizona, as well as from the Atacama Cosmology Telescope in Chile.

Related: 'The universe has thrown us a curveball': Largest-ever map of space reveals we might have gotten dark energy totally wrong

Using DESI observations, the team stacked images of approximately 7 million galaxies to measure the faint halos of ionized hydrogen gas at the galaxies' edges. These halos are typically too faint to be seen by normal methods. So instead, the team measured how much the gas dimmed or brightened radiation from the cosmic microwave background — leftover radiation from the Big Bang that is prevalent throughout the universe.

The team also discovered that the clouds of ionized hydrogen formed ghostly, nearly invisible filaments between galaxies. If it connects most of the galaxies in the universe, this cosmic web would easily span far enough to account for the previously undetected matter.

Black holes on duty

The discovery also may change what we know about black hole behavior. Scientists initially thought the supermassive black holes at the hearts of most galaxies only spewed jets of gas early in their life cycles. But the presence of such extensive diffuse gas clouds indicates that these black holes probably become active more frequently than previously thought.

"One of the hypotheses is that [black holes] turn on and off occasionally in what is called a duty cycle," first study author Boryana Hadzhiyska, an astronomer at the University of California, Berkeley, said in the statement.

The next step will be to incorporate the new measurements into existing cosmological models. "There are a huge number of people interested in using our measurements to do a very thorough analysis that includes this gas," Hadzhiyska said.

A theoretical phenomenon proposed by famed physicist Stephen Hawking may have changed the shape of the universe, new research proposes.

In the 1970s, Hawking introduced a groundbreaking concept: Black holes — traditionally viewed as cosmic entities that engulf everything in their vicinity — might emit radiation similar to the way a heated object does. This phenomenon, now known as Hawking radiation, remains theoretical due to the minimal emission power calculated for stellar and supermassive black holes.

However, a recent study published in the Journal of Cosmology and Astroparticle Physics proposes that this elusive radiation could have significantly influenced the universe's early structure. The researchers suggest that primordial black holes, hypothesized to have existed shortly after the Big Bang, might have emitted intense Hawking radiation, leaving detectable imprints on the cosmos we observe today.

"An intriguing possibility is that the early universe underwent a phase in which its energy density was dominated by primordial black holes, which then evaporated through Hawking radiation," the scientists wrote in their study. "This is a generic consequence of ultra-light primordial black holes [...], as even a small initial abundance of such objects would quickly come to dominate the universe as it expanded."

Deciphering Hawking radiation

Hawking's seminal work partially merged the mathematical frameworks of general relativity and quantum mechanics — two foundational theories of physics that have yet to be fully unified — to explore black hole physics. He found that black holes, once thought to be inescapable traps, could actually emit particles, including photons (light).

Related: 'The universe has thrown us a curveball': Largest-ever map of space reveals we might have gotten dark energy totally wrong

Importantly, the emission rate decreases as the black hole's mass increases, meaning that black holes that formed from collapsing stars, as well as the supermassive ones that anchor galaxies, would radiate so weakly that their Hawking radiation would be impossible to detect with current instruments.

However, it is widely believed that in the early universe, much smaller black holes — each with a mass of less than 100 tons — could have formed. These so-called primordial black holes would have emitted particles at a rate significant enough to influence cosmic structures such as galaxies and clusters.

"Various cosmological scenarios predict the formation of black holes in the early universe," the authors wrote. "For example, primordial black holes may have formed from the gravitational collapse of overdense regions."

Notably, the Hawking radiation from these primordial black holes would encompass all particle types, including those hypothetical particles that interact weakly with known particles described by the Standard Model. This implies that such radiation could offer a unique avenue for studying these elusive particles, which may be impossible to produce in particle accelerators.

Investigating primordial black holes' impact

Employing Einstein's general relativity equations, the research team analyzed various particles with different masses and spins to determine their impact on the universe's matter distribution. For example, if a large number of light, fast-moving particles were present, they could impede the formation of small galaxies, as such particles would have difficulty gathering in sufficient quantities to form dense structures. The team also investigated other possible effects these particles might have.

"If any of these particles are stable and persist to the present day, we call them Hawking relics," the researchers explained in their paper. "Massless Hawking relics would contribute to the cosmic radiation budget [...] and could be detected in measurements of the cosmic microwave background."

The scientists meticulously examined how Hawking relics might influence the current cosmic structure. Although they didn't find direct evidence of these relics, their analysis allowed them to constrain the properties of both the particles and the primordial black holes that could have emitted them.

"If there were a meaningful number of evaporating black holes during the period when the first nuclei were formed, the predicted number of atomic nuclei in the universe would be incorrect," the physicists wrote. "We thus require that the primordial black holes evaporate before this period, which gives us an upper bound on their mass of five hundred tons."

The team also explored the hypothesis that Hawking relics could constitute dark matter, which accounts for approximately 85% of all matter in the universe. Their findings suggest Hawking relics are not a good match for dark matter.

"We constrain the abundance of warm Hawking relics to be less than ∼ 2% of dark matter, even if primordial black holes produced multiple different kinds of relic particles," the scientists note.

Future prospects

Although current observations haven't confirmed the existence of Hawking relics, the researchers remain optimistic. They believe that forthcoming instruments with enhanced precision could detect these relics, thereby validating the existence of Hawking radiation and primordial black holes and enabling experimental studies of their properties.

"The discovery of a Hawking relic would open a window to the thermal state of the [early] universe [...]," the team wrote. “This would not only be important for early-universe cosmology, but it would also open a new frontier of particle physics beyond the Standard Model and give the first observational evidence for Hawking radiation, black-hole evaporation, and primordial black holes."

In summary, while Hawking radiation remains a theoretical construct, its potential role in shaping the universe's early structure offers a compelling avenue for research. The study of primordial black holes and their possible remnants could provide profound insight into both cosmology and particle physics, thus bridging gaps in our understanding of the universe's infancy.

The European Space Agency (ESA) has just released the first batch of data from the groundbreaking Euclid space telescope, which was built to study the mysteries of dark matter and dark energy throughout the universe.

The survey data, released March 19, includes initial scans of three regions that Euclid will observe regularly, as well as detailed classifications of more than 380,000 galaxies — a mere 0.4% of the galaxies scientists expect to catalog over the mission's planned six-year lifespan.

"With the release of the first data from Euclid's survey, we are unlocking a treasure trove of information for scientists to dive into and tackle some of the most intriguing questions in modern science," Carole Mundell, ESA's director of science, said in a statement.

Euclid, which launched in July 2023 and began collecting data in February 2024, aims to map the large-scale structure of the universe. Understanding this structure through the shapes, sizes and distribution of galaxies could help scientists determine the nature of dark matter and dark energy — two mysterious phenomena that together make up an estimated 95% of the universe but do not interact with light and so cannot be studied directly.

"The full potential of Euclid to learn more about dark matter and dark energy from the large-scale structure of the cosmic web will be reached only when it has completed its entire survey," Clotilde Laigle, a Euclid Consortium scientist at Institut d'Astrophysique de Paris, said in the statement. "Yet the volume of this first data release already offers us a unique first glance at the large-scale organization of galaxies, which we can use to learn more about galaxy formation over time."

Related: 'The universe has thrown us a curveball': Largest-ever map of space reveals we might have gotten dark energy totally wrong

The March 19 release includes a single scan of each of the deep-field regions, three areas of the sky that Euclid will revisit multiple times to observe far into the universe. In these initial images, the telescope captured 26 million galaxies, the most distant of which are 10.5 billion light-years away. (A light-year is the distance light can travel in one year — roughly 5.9 trillion miles or 9.5 trillion kilometers.)

"We will observe each deep field between 30 and 52 times over Euclid's six year mission, each time improving the resolution of how we see those areas, and the number of objects we manage to observe," Valeria Pettorino, Euclid project scientist at ESA, said in the statement. "Just think of the discoveries that await us."

Over the course of its planned mission, Euclid will likely capture images of 1.5 billion galaxies, sending about 100 gigabytes of data back to Earth each day. To process this tsunami of information, Euclid scientists are turning to artificial intelligence (AI). Last year, nearly 10,000 volunteers with citizen science project Galaxy Zoo helped train the "ZooBot" AI algorithm to recognize various features of galaxies, such as spiral arms, in early Euclid images.

"We're looking at galaxies from inside to out, from how their internal structures govern their evolution to how the external environment shapes their transformation over time," Laigle said in the statement. "Euclid is a goldmine of data and its impact will be far-reaching, from galaxy evolution to the bigger-picture cosmology goals of the mission."

Astronomers studying the largest-ever map of the cosmos have found hints that our best understanding of the universe is due a major rewrite.

The analysis, which looked at nearly 15 million galaxies and quasars spanning 11 billion years of cosmic time, found that dark energy — the presumed-to-be constant force driving the accelerating expansion of our universe — could be weakening.

Or at least this is what the data, collected by the Dark Energy Spectroscopic Instrument (DESI), suggest when combined with information taken from star explosions, the cosmic microwave background and weak gravitational lensing.

If the findings hold up, it means that one of the most mysterious forces controlling the fate of our universe is even weirder than first thought — and that something is very wrong with our current model of the cosmos. The researchers' findings were published in multiple papers on the preprint server arXiv and presented March 19 at the American Physical Society's Global Physics Summit in Anaheim, California, so they have not yet been peer-reviewed.

"It's true that the DESI results alone are consistent with the simplest explanation for dark energy, which would be an unchanging cosmological constant," co-author David Schlegel, a DESI project scientist at the Lawrence Berkeley National Laboratory in California, told Live Science. "But we can't ignore other data that extend to both the earlier and later universe. Combining [DESI's results] with those other data is when it gets truly weird, and it appears that this dark energy must be 'dynamic,' meaning that it changes with time."

The evolving cosmos

Dark energy and dark matter are two of the universe's most puzzling components. Together they make up roughly 95% of the cosmos, but because they do not interact with light, they can't be detected directly.

Yet these components are key ingredients in the reigning Lambda cold dark matter (Lambda-CDM) model of cosmology, which maps the growth of the cosmos and predicts its end. In this model, dark matter is responsible for holding galaxies together and accounts for their otherwise inexplicably powerful gravitational pulls, while dark energy explains why the universe's expansion is accelerating.

Related: Could the universe ever stop expanding? New theory proposes a cosmic 'off switch'

But despite countless observations of these hypothetical dark entities shaping our universe, scientists are still unsure where they came from, or what they even are. Currently, the best theoretical explanation for dark energy is made by quantum field theory, which describes the vacuum of space as filled with a sea of quantum fields that fluctuate, creating an intrinsic energy density in empty space.

In the aftermath of the Big Bang, this energy increases as space expands, creating more vacuum and more energy to push the universe apart faster. This suggestion helped scientists to tie dark energy to the cosmological constant — a hypothetical inflationary energy, growing with the fabric of space-time throughout the universe's life. Einstein named it Lambda in his theory of general relativity.

"The problem with that theory is that the numbers don't add up," said Catherine Heymans, a professor of astrophysics at the University of Edinburgh and the Astronomer Royal for Scotland who was not involved in the study. "If you say: 'Well, what sort of energy would I expect from this sort of vacuum?' It's very, very, very, very different from what we measure," she told Live Science.

"It's kind of exciting that the universe has thrown us a curveball here," she added.

Scanning the dark universe

To figure out if dark energy is changing over time, the astronomers turned to three years' worth of data from DESI, which is mounted on the Nicholas U. Mayall 4-meter Telescope in Arizona. DESI pinpoints the monthly positions of millions of galaxies to study how the universe expanded up to the present day.

By compiling DESI's observations, which includes nearly 15 million of the best measured galaxies and quasars (ultra-bright objects powered by supermassive black holes), the researchers came up with a strange result.

Taken on their own, the telescope's observations are in "weak tension" with the Lambda-CDM model, suggesting dark energy may be losing strength as the universe ages, but without enough statistical significance to break with the model.

But when paired with other observations, such as the universe's leftover light from the cosmic microwave background, supernovas, and the gravitational warping of light from distant galaxies, the likelihood that dark energy is evolving grows.

In fact, it pushes the observations' disagreement with the standard model as far as 4.2 Sigma, a statistical measure on the cusp of the five-Sigma result physicists use as the "gold standard" for heralding a new discovery.

Related: After 2 years in space, the James Webb telescope has broken cosmology. Can it be fixed?

Whether this result will hold or fade over time with more data is unclear, but astrophysicists are growing confident that the discrepancy is less likely to disappear.

"These data seem to indicate that either dark energy is becoming less important today, or it was more important early in the universe," Schlegel said.

Astronomers say that further answers will come from a flotilla of new experiments investigating the nature of dark matter and dark energy in our universe. These include the Euclid space telescope, NASA's Nancy Grace Roman Space Telescope, and DESI itself, which is now in its fourth of five years scanning the sky and will measure 50 million galaxies and quasars by the time it's done.

"I think it's fair to say that this result, taken at face-value, appears to be the biggest hint we have about the nature of dark energy in the [rough] 25 years since we discovered it," Adam Riess, a professor of astronomy at Johns Hopkins University who won the 2011 Nobel Prize in physics for his team's 1998 discovery of dark energy, told Live Science. "If confirmed, it literally says dark energy is not what most everyone thought, a static source of energy, but perhaps something even more exotic."

Dark energy may have switched directions sometime in the distant past — and this violent transition may explain why cosmological observations aren't adding up, researchers propose in a new paper.

The modern picture of the evolution of the universe is known as ΛCDM (or lambda-CDM), for dark energy (represented by the Greek letter Λ) and cold dark matter. Dark energy is the mysterious force driving the accelerating expansion of the universe, and cold dark matter refers to the mysterious, invisible substance that provides most of the mass of almost every single galaxy.

This model has explained a wide variety of observations, such as the behavior of galaxies and clusters, the growth of large-scale structures, and the appearance of the cosmic microwave background. But in recent years, two troubling tensions have popped up.

One such problem, known as the Hubble tension, is a difference in measuring the present-day expansion rate of the universe, a number known as the Hubble constant. Probes of the distant, early universe seem to be giving estimates significantly lower than probes of the nearby, late universe do.

Related: After 2 years in space, the James Webb telescope has broken cosmology. Can it be fixed?

Related to this issue is the second problem, known as the sigma-8 tension. This is a measure of how clumpy matter is in the universe, and once again, different probes are yielding different results.

A cosmic slowdown

Something in the ΛCDM model has to be wrong, but we're not sure what. One hypothesis is that dark energy might be more dynamic than we originally thought. In the usual ΛCDM picture, dark energy is a cosmological constant. It stays the same through cosmic history.

But in a recent model that's been gaining interest, dark energy changes. And not by a little; it undergoes a complete phase transition, from decelerating the universe to accelerating the universe.

Now, adding a twist to that theory, a research team has explored the possibility that the phase change is even more dramatic. In a paper posted to the preprint server arXiv in February but not yet peer-reviewed, dark energy doesn't just switch signs; it also changes strength, so that it powers an acceleration differently than it powers a deceleration.

Then, the researchers tested their model against a wide variety of observations and datasets. These included the Planck space observatory's measurements of the cosmic microwave background, the oldest light we can see in the universe; a measurement of a phenomenon called the baryon acoustic oscillation, a pattern in the arrangement of galaxies at very large scales; the Pantheon dataset of supernova distance measures; and a weak lensing map that provides details accounting for the effects of dark matter.

They found that the new model alleviated some of the Hubble and sigma-8 tensions, and thus they contend that this approach might be a promising way forward.

That said, the researchers noted that this model isn't exactly grounded in known physics. It's just a toy, a way to explore the physical consequences of a model without knowing the underlying physics. But because it seems like a promising direction, this approach could motivate theorists to come up with mechanisms to explain how dark energy might switch like this.

No matter what, it appears that the universe — especially dark energy — is more complicated than we assumed.

Five decades ago, famed astrophysicist Stephen Hawking theorized that the Big Bang may have flooded the universe with tiny black holes. Now, researchers believe they may have seen one explode.

In Feb. 2025, the European collaboration KM3NeT — which consists of underwater detectors off the coasts of France, Italy and Greece — announced the discovery of a stupendously powerful neutrino. This ghostly particle had an energy of around 100 PeV — over 25 times more energetic than the particles accelerated in the Large Hadron Collider, the world's most powerful atom smasher.

Physicists have struggled to come up with an explanation for such an energetic neutrino. But now, a team of researchers who were not involved in the original detection have proposed a surprising hypothesis: The neutrino is the signature of an evaporating black hole. The team described their proposal in a paper that was uploaded to the arXiv database and has not been peer-reviewed yet.

Hawking's elephant-size black holes

In the 1970s, Hawking realized that black holes aren't entirely black. Instead, through complex interactions between the black hole event horizon and the quantum fields of space-time, they can emit a slow-but-steady stream of radiation, now known as Hawking radiation. This means black holes evaporate and eventually disappear. In fact, as the black hole gets smaller, it emits even more radiation, until it essentially explodes in a firestorm of high-energy particles and radiation — like the neutrino spotted by the KM3Net collaboration.

Related: Stephen Hawking's black hole radiation paradox could finally be solved — if black holes aren't what they seem

But all known black holes are very large — at least a few times the mass of the sun, and often significantly larger. It will take well over 10^100 years for even the smallest known black holes to die. If the KM3NeT neutrino is due to an exploding black hole, it has to be much smaller — somewhere around 22,000 pounds (10,000 kilograms). That's about as heavy as two fully grown African elephants, compressed into a black hole smaller than an atom.

The only known potential way to produce such tiny black holes is in the chaotic events of the early Big Bang, which may have flooded the cosmos with "primordial" black holes. The smallest primordial black holes produced in the Big Bang would have exploded long ago, while larger ones might persist to the present day.

Unfortunately, a 22,000-pound black hole should not survive all the way from the Big Bang to the present day. But the authors pointed out that there might be an additional quantum mechanism — known as "memory burden" — that allows black holes to resist decay. This would allow a 22,000-pound black hole to survive for billions of years before it finally exploded, sending a high-energy neutrino toward Earth in the process.

Primordial black holes might be an explanation for dark matter — the invisible substance that accounts for most of the matter in the universe — but so far, searches for them have turned up empty. This new insight may provide an intriguing clue. The researchers found that if primordial black holes of this mass range are abundant enough to account for all the dark matter, they should be exploding somewhat regularly. They estimated that if this hypothesis is correct, the KM3NeT collaboration should see another showstopping neutrino in the next few years.

If that detection happens, then we may just have to radically rethink the way we approach dark matter, high-energy neutrinos and even the physics of the early universe.

The most powerful cosmic rays raining down on Earth may come not from distant corners of the universe but from heavy dark matter particles that annihilate themselves in our own backyard.

Cosmic rays are high-energy particles that constantly stream through the cosmos. They are largely made of protons, but they can occasionally be made of the nuclei of heavy elements, such as helium and even iron. Despite being microscopic, they pack a punch. Each one travels at nearly the speed of light, and the fastest ones have energies trillions of times stronger than our most powerful particle accelerators.

Astrophysicists understand the origins of most cosmic rays. Any time there is an energetic event in the universe, it's likely to produce a shower of cosmic rays. This can include supernovas, merging stars and matter being swallowed by black holes.

Related: 32 physics experiments that changed the world

But we do not fully understand the origins of the most powerful cosmic rays. The problem is that, although there are plenty of energetic sources for them, those sources are billions of light-years away. These superenergized particles cannot travel those great distances without slowing down significantly. So perhaps their origins are much closer to home.

And perhaps their origins are much more exotic than a mere cosmic explosion. In a recent paper that has not yet been peer-reviewed, a Russian astrophysicist proposes that the most powerful cosmic rays originate from an exotic form of dark matter.

Heavy, dark, and self-destructive

This dark matter particle would itself be very heavy — far heavier than even the heaviest known particle, the top quark. Known as a scalaron, this dark matter particle would have been created in the earliest moments of cosmic history, during an epoch known as inflation, when the universe became many orders of magnitude larger in an instant.

Since then, the scalaron has largely remained in the background, as it's invisible to light and affects the rest of the universe only through its gravitational influence. But very, very rarely, two scalarons can intersect — and, in the process, annihilate each other in a flash of energy. That flash can include extremely energetic cosmic rays.

Scalarons are everywhere, so they can produce ultra-high-energy cosmic rays within our own galaxy. But this is where fun ideas must meet observational reality. If the scalarons intersect too often, they will produce more high-energy cosmic rays than we observe. Conversely, if they don't intersect and annihilate often enough, then it won't match known observations.

It just so happens that it's possible for annihilating scalarons to be responsible for the number of high-energy cosmic-ray detections we have; the densities and interaction frequencies match the known behavior of dark matter.

However, this is a tenuous hypothesis. The production of scalarons in the early universe requires adjustments to Einstein's theory of general relativity that may not hold up to further scrutiny. And there are competing proposals for explaining the highest-energy cosmic rays. For instance, they may be produced inside molecular clouds in our own galaxy, without requiring dark matter.

Still, it's an interesting idea, and it shows how the extremes of our universe can be used as a test bed for radical ideas. By continuing to pursue these ideas, we can find other ways to test them observationally. And if this idea works out, it will give us a window into not just dark matter but the early universe itself.

The Euclid space telescope has captured a stunning and rare "Einstein ring" magnifying light from the depths of the universe.

The image shows a faint halo surrounding the nearby galaxy NGC 6505, created as the galaxy warps and magnifies light from an even more distant galaxy behind it.

This type of magnification is called gravitational lensing and was first predicted by Albert Einstein in 1915. The powerful magnification means that the resulting image shows us light from an unnamed and undiscovered galaxy 4.42 billion light-years into the universe's past — even though NGC 6505 is only 590 million light-years away, in Earth's "cosmic backyard." The researchers published their findings Feb. 10 in the journal Astronomy and Astrophysics.

"An Einstein ring is an example of strong gravitational lensing," study lead author Conor O'Riordan, a researcher at the Max Planck Institute for Astrophysics in Germany, said in a statement. "All strong lenses are special, because they're so rare, and they're incredibly useful scientifically. This one is particularly special, because it's so close to Earth and the alignment makes it very beautiful."

Magnifying the stars

Einstein's theory of general relativity describes the way massive objects warp the fabric of the universe, called space-time. Gravity, Einstein discovered, isn't produced by an unseen force but by space-time curving and distorting in the presence of matter and energy.

Related: Mysterious 'Green Monster' lurking in James Webb photo of supernova remnant is finally explained

This curved space, in turn, sets the rules for how energy and matter move. Even though light travels in a straight line, light traveling through a highly curved region of space-time, such as the region around a massive galaxy, also travels in a curve — bending around the galaxy and splaying out into a halo.

The new image was retrieved from data collected by the Euclid space telescope during its early testing phase in September 2023. Launched on July 1, 2023, Euclid was designed to compile wide-lens images to help scientists hunt for two of the universe's most mysterious components: dark matter and dark energy.Researchers think dark matter and dark energy together make up about 95% of the universe, but they do not interact with light so can't be detected directly.

Instead, scientists study these mysterious components by observing the way they interact with the visible universe around them: Dark matter can be seen by observing its gravitational warping effects on galaxies; and dark energy can be spotted in the force propelling the universe's runaway expansion.

Astronomers have identified hundreds of Einstein rings. But these phenomena aren't sought after just because they make pretty pictures. Because the rings magnify light, scientists can reconstruct this light into its original, pre-bent, form, which can enhance the details astronomers are able to spot in very distant galaxies.

Also, because the extent to which light bends depends on the strength of the gravitational field of the object that bends it, Einstein rings can act as a cosmic scale for gauging the masses of galaxies and black holes, including how much dark matter they contain.

"I find it very intriguing that this ring was observed within a well-known galaxy, which was first discovered in 1884," study co-author Valeria Pettorino, a project scientist working on Euclid, said in the statement. "The galaxy has been known to astronomers for a very long time. And yet this ring was never observed before. This demonstrates how powerful Euclid is, finding new things even in places we thought we knew well. This discovery is very encouraging for the future of the Euclid mission and demonstrates its fantastic capabilities."

Euclid is partway through its six-year mission to catalog a third of the entire night sky by capturing thousands of wide-angle images. All told, Euclid will capture light from more than a billion galaxies that are up to 10 billion years old, according to the European Space Agency.

Once this is done, astronomers will use Euclid's images to create two maps: one of the gravitational lensing of galaxies that should reveal concentrations of dark matter, and the other of shock waves called baryon acoustic oscillations that can trace dark energy.

A recent study offers a potential solution to one of cosmology's most perplexing mysteries: how supermassive black holes in the early universe grew so massive, so quickly. By introducing a novel physics model, researchers explain how supermassive black hole seeds could have formed through the collapse of the mysterious entity known as dark matter.

Dark matter, an enigmatic ingredient of the universe that is effectively invisible and interacts with other matter only through gravity, provides the structural framework for galaxy formation. Despite its critical role, its nature remains one of the greatest mysteries in astrophysics. The standard cosmological model assumes that dark matter interacts solely through gravity, but this framework struggles to explain the existence of supermassive black holes as early as 800 million years after the Big Bang.

Observations from telescopes like the James Webb Space Telescope (JWST) have revealed quasars — extremely bright objects powered by supermassive black holes — at these early epochs, and they boast masses more than a billion times that of the sun. Traditional models that rely on gas accretion and mergers with other black holes and galaxies fall short of explaining how these black holes could have grown so massive in such a short time.

Ultra self-interacting dark matter comes to the rescue

To address these challenges, the team proposed a subcomponent of dark matter called ultra self-interacting dark matter. Unlike standard dark matter, this component — which would constitute less than 10% of the total dark matter in the early universe — would exhibit strong self-interactions. This property would allow ultra self-interacting dark matter particles to clump together in the centers of galactic halos.

"The dark matter self-interaction is a necessary component because the dark matter particles need a way to scatter off one another, much stronger than just gravitational interactions," study co-author Grant Roberts, a doctoral student at the University of California, Santa Cruz, told Live Science in an email. "This scatter causes the dark matter to bunch up in the very inner central regions of the galaxy, which allows them to collapse into supermassive black hole seeds."

Related: 5 fascinating facts about the Big Bang, the theory that defines the history of the universe

These strong self-interactions would drive ultra self-interacting dark matter particles toward galactic centers, where they would form dense cores that would eventually collapse into black holes. If this process occurred early in a galaxy's evolution, it could have seeded supermassive black holes, enabling them to grow through conventional gas accretion processes. Importantly, the model bypassed the slow timescales of traditional supermassive black hole formation mechanisms, allowing for rapid growth while remaining consistent with other astrophysical observations.

"Our key findings are that we are able to form supermassive black hole seeds and grow them to their observed masses within current observational limits," Roberts added.

Testing the theory with quasar observations

To validate their model, the researchers analyzed a sample of three quasars with well-measured masses and ages. These objects, observed by JWST and other telescopes, serve as critical benchmarks for calibrating the ultra self-interacting dark matter model.

The team found that their model successfully reproduced the observed quasars' parameters, even under different assumptions about the velocity dependence of the dark matter self-interaction strength. "What makes our model more favorable is that we can directly calibrate how strong the self-interaction is, as well as how small this fraction needs to be, from the age and mass of the observed supermassive black holes," Roberts explained.

One of the most exciting aspects of the ultra self-interacting dark matter model is its testable predictions. The hypothesis suggests the existence of intermediate-mass black holes in dwarf galaxies — smaller, less-massive galaxies than our own. Observing such black holes and their distribution could provide direct evidence for the model.

"If telescopes look at these dwarf galaxies and measure the mass of these black holes, we can compare directly with what our model predicts," Roberts said. The model also predicts the number and sizes of these black holes, which can be cross-verified with future observational data.

The study, published Jan. 14 in the Journal of Cosmology and Astroparticle Physics, emphasizes the potential for further insights from JWST, which continues to uncover new supermassive black holes at ever-greater distances. These discoveries could place tighter constraints on the timescales of supermassive black hole formation and refine the parameters of the ultra self-interacting dark matter model.

"With the advent of even [more ancient] supermassive black holes being discovered by JWST, we will be able to put further constraints on our model parameters," Roberts noted. "As JWST finds more of these black holes, we'd like to see how our new models impact what we predict for intermediate-mass black hole masses and abundances in the universe.

Dark matter can't be too heavy or it might break our best model of the universe, new research suggests.

We have an abundance of evidence that something fishy is happening in the universe. Stars orbit within galaxies far too quickly. Galaxies move around inside clusters much too fast. Structures grow and evolve too rapidly. If we count only the matter we can see, there simply isn't enough gravity to explain all of these behaviors.

The vast majority of cosmologists believe all of these phenomena can be explained through the presence of dark matter, a hypothetical form of matter that is massive, electrically neutral and hardly, if ever, interacts with normal matter. This dark matter makes up most of the mass in the universe, far outweighing the amount of luminous matter.

The identity of dark matter remains a mystery, as experiments designed to detect a stray, rare collision have failed to turn up anything. But these experiments have focused on targeting a specific mass range: roughly 10 to 1,000 giga-electron volts (GeV). (A GeV is equivalent to 1 billion electron volts.) That's in the range of the heaviest known particles, like the W boson and the top quark. For decades, theorists favored this mass range because several simple extensions of the Standard Model of particle physics predicted the existence of such particles.

Because we haven't found anything yet, though, we've started to wonder if dark matter might be lighter or heavier than we thought. But heavier dark matter runs into some serious issues, according to a new paper published to the preprint database arXiv.

The problem is that dark matter does sometimes interact with normal matter, if only rarely. But in the early universe, when the cosmos was much hotter and denser, these interactions were much more frequent. Eventually, as the universe expanded and cooled, these interactions slowed and then stopped, leading the dark matter to "freeze out" and remain silent in the background.

Related: Something invisible and 'fuzzy' may lurk at the Milky Way's center, new research suggests

While there are many, many models of potential dark matter candidates, many interact with regular particles through exchanges involving the Higgs boson — a fundamental particle that interacts with almost all other particles and, through those interactions, imbues those particles with mass.

We know the mass of the Higgs boson: around 125 GeV. The researchers found that this mass puts a fundamental upper limit on the possible mass of most dark matter candidates.

The problem is that all interactions in physics are two-way streets. The Higgs talks to both dark matter and regular matter and, in many models, mediates interactions between them. But both kinds of matter also talk back to the Higgs. These interactions appear as slight modifications to the Higgs boson's mass.

For Standard Model particles, we can calculate these corrections and feedback interactions, which is how theorists predicted the mass of the Higgs boson well before it was detected.

The researchers found that if the dark matter particle had a mass greater than a few thousand GeV, its contribution to the Higgs mass would be incredibly important, driving it away from its observed value. And because the Higgs is so central to determining many other fundamental physics, it would essentially shut down particle interactions altogether.

There are possibilities to get around this restriction, however. Dark matter might not interact with regular particles at all, or the interaction might happen through some exotic mechanism that doesn't involve the Higgs. But those models are few and far between and require a lot of fine-tuning and extra steps.

Or it could be that dark matter is lighter than we thought. If we don't think heavy dark matter is a viable candidate, then as we continue to learn about this mysterious component of the universe, we can instead focus our efforts in the other direction. There has already been a surge of interest in axions, ultralight particles that are predicted in some particle physics models and might be a viable dark matter candidate.

On the experimental side, if this result is confirmed and holds to be a widespread restriction on dark matter particle mass, we can refine and redesign our experiments to search for low-mass, instead of high-mass, particles.

Originally posted on Space.com.

What it is: The Antlia Cluster of galaxies (also called Abell S636)

Where it is: 130 million light-years distant in the constellation Antlia, also known as the Air Pump

When it was shared: Jan. 1, 2025

Why it's so special: Astronomers used a telescope in Chile equipped with a highly sensitive camera to capture the best-ever image of a cluster of galaxies near our Milky Way.

The researchers pointed the Víctor M. Blanco 4-meter Telescope's Dark Energy Camera (DECam) at the Virgo Cluster in order to help solve one of astronomy's biggest mysteries — the nature of dark matter.

Also available as a zoomable version, the image reveals NGC 3268 (center) and NGC 3258 (lower right) — both massive, lenticular galaxies that have a central bulge like the Milky Way but no spiral arms, and where star formation has fizzled out, according to NASA. One study suggests that the two galaxies are gradually merging, which may indicate that the Antlia Cluster is, or was, two separate clusters.

However, what fascinates astronomers is the Antlia Cluster's rich diversity of galaxies. Technological advances have helped reveal not just lenticular galaxies but also irregular galaxies, dwarf galaxies, compact ellipticals and blue compact dwarfs. Even odder, little-seen galaxy types are suspected to be hiding within Antlia — many of which are thought to be rich in dark matter.

This strange substance appears to make up about 25% of the universe. Dark matter may be made up of invisible particles that absorb, reflect or emit no light or energy and as a result is impossible for telescopes and cameras to detect, according to NASA. However, its gravitational effect on visible matter can be seen everywhere astronomers look — especially within the catwalk of galaxy types in the Antlia Cluster.

The DECam, built by the U.S. Department of Energy, is a 570-megapixel camera in Cerro Tololo Inter-American Observatory in Chile, a Program of the National Science Foundation's National Optical Infrared Astronomy Research Lab.

For more sublime space images, check out our Space Photo of the Week archives.

In this excerpt from "Matter: The Magnificent Illusion" (Polity, 2025, translated by Edward Williams), author and physicist Guido Tonelli delves into the discovery of dark energy, and the multiple attempts to explain this strange phenomenon that appears to be driving the ever increasing expansion of the universe.

The discovery of dark energy was a real surprise for everyone, including those working on it. When it happened, in 1998, the astronomers who were the first to find themselves in the presence of such surprising data, couldn't believe their eyes. And yet the results left no doubt.

The velocity at which the universe had expanded was not constant; on the contrary, for quite some time now it had been increasing significantly. Everything was moving away from everything at an increasingly frenetic rhythm.

What scientists were seeing contradicted what they were expecting; the idea of the accelerated expansion of the universe was counterintuitive. Everyone expected that the attraction exerted by gravity would slowly reduce the expansion velocity of space-time, whereas the exact opposite was happening.

For many years, different teams of scientists tried to understand whether what the data was pointing to was real or whether, on the other hand, errors had been made in the measurements. In the end, they gave in to the evidence. There was no doubt that a new natural phenomenon was being observed, however completely unexpected it was. In the end even the Royal Swedish Academy of Sciences in Stockholm recognized the importance of the work of Saul Perlmutter, Brian Schmidt and Adam Riess, the three astronomers who had carried out the early research, rewarding their discovery with the 2011 Nobel Prize.

Right from the earliest moments, in an attempt to explain this strange phenomenon, the expression dark energy was coined, indicating the complete ignorance of the mechanism that produced it: an absolutely unknown form of energy seemingly pushing everything away from everything else and growing as the dimensions of the universe grow.

Some imagined a kind of anti-gravity, an extremely strange behaviour of gravity which from being attractive, as we know it, becomes repulsive over great distances. Others imagined a kind of vacuum energy, a positive energy, which creates a kind of negative pressure, thereby pushing everything towards dilation.

The idea that the void contains positive energy which makes it expand goes back many years. And Albert Einstein was the first to come up with it. To make the universe static, that is to counterbalance the effect of gravity, which, acting alone, would sooner or later make everything collapse into one point, Einstein added a positive constant, called the "cosmological constant" into his equations by hand, that is to say arbitrarily. This classification served to build a balance; making the universe expand countered the effects of gravity and made it stable.

Later, when it was discovered that everything had had a turbulent beginning and that galaxies were still moving apart from one another, Einstein regretted this choice, to the extent of referring to it as one of the worst blunders of his life. In fact, with a universe arising from an ultra-dense and super-incandescent singularity, there was no need for this further impetus to expansion to produce a condition of equilibrium. The curious thing is that nobody, least of all Einstein, could predict that by the end of the 20th-century, the discoveries made by Perlmutter, Schmidt and Riess would bring his cosmological constant back into vogue. And so, it seems as if nature will always end up proving Einstein right, even when the great scientist is convinced that he's clearly wrong.

In this case, too, precious information about the presence and distribution of dark energy can be extracted by analyzing the tiniest inhomogeneity in cosmic background radiation and the gravitational lens effects produced by galaxies and clusters. It's curious to discover that it is still light which allows us to take a look at this shady side of the cosmos.

The distribution of dark energy in the cosmos is very homogeneous. It behaves quite differently from matter, whether ordinary matter or dark matter. These latter material substances have reticular distributions with high- density nodes and filaments alternating with broad empty spaces. On the contrary, dark energy is distributed uniformly throughout space and seems to occupy the entire volume of the universe quite happily, exerting a repulsive force on everything.

In an attempt to understand the origin of this mysterious form of energy, scientists have ascertained whether the expansion velocity is the same, over a given period, for all the different regions of the universe. They also realized that this phenomenon has only become dominant in the last billions of years. For a long period, the universe expanded following a very different rhythm from the current one.

Various hypotheses have been tested, including the idea that we are dealing with a new fundamental force or an anomalous behaviour of gravity or even the presence in the fabric of spacetime of very particular structures, similar to defects in its regular pattern. But, as yet, nobody has managed to understand what gives rise to this strange phenomenon, and explaining dark energy remains one of the most formidable challenges of modern science.

While the mystery surrounding its origins remains, the precise measurements taken of the effects of dark energy on the geometry of the universe and on the spatial fluctuations in the density of matter have made it possible to quantify the weight of this component in the material composition of the universe.

The result is sensational; dark energy contributes around 68% of the total mass. Around two-thirds of the universe is made up of this most mysterious of components. Totalling up the contribution of dark energy, we obtain a frankly embarrassing result. Despite the great progress made by contemporary science, we are forced to admit that we don't know anything about 95% of everything that surrounds us.

Reprinted with permission from Matter: The Magnificent Illusion by Guido Tonelli, available from Polity

Galaxies may be anchored to giant "dark stars" — clumps of invisible matter sitting at their cores, new research suggests.

Although astronomers have an abundance of evidence that most of the mass in any given galaxy is invisible, they do not yet know the identity of this "dark matter." In recent decades, the most promising hypothesis has been that dark matter is made of some kind of heavy particle that rarely, if ever, interacts with light or other matter. But this hypothesis struggles to explain the relatively low densities of galaxy cores, because simulations of dark matter's behavior predict that it should easily clump up to extremely high densities, which does not match observations.

One possible answer to this problem is that the dark matter particles are incredibly light — billions of times less massive than the neutrino, the lightest particle currently known. Dubbed "fuzzy" dark matter, these hypothetical particles are so light that their quantum-wave nature manifests on larger, macroscopic — even galactic — scales. This means they can stabilize into giant clumps of invisible matter, forming dark stars.

This is especially interesting because these dark stars can be extended in space for thousands of light-years but still have relatively low masses, since the particles are so light. Thus, they can potentially form the cores of galaxies, providing the bulk of these galaxies' mass without creating superhigh densities at the galactic centers.

But galaxies are made of more than dark matter — fuzzy or otherwise. They also contain normal matter, distributed in the form of diffuse gas clouds and stars, and it's those elements that astronomers can actually observe. So, to test this idea, we need to understand the link between fuzzy dark matter and normal matter within a galaxy.

Related: 800-mile-long 'DUNE' experiment could reveal the hidden dimensions of the universe

The 'fuzz' in our stars

In a paper published Dec. 17, 2024 on the preprint server arXiv, an international team of astrophysicists explored how galaxies might evolve in response to fuzzy dark matter. For this first step, they did not attempt to recreate an entire complex galaxy. Instead they built a simple toy model that contained only two components: a large percentage of fuzzy dark matter and a smaller percentage of a simple, ideal gas.

They then computed how these two components would evolve under their mutual gravitational influence. They found that, despite initially random behavior, the fuzzy dark matter quickly collected into a large clump in the center, with more diffuse clouds of dark matter surrounding it.

The gas followed along, mixing with the fuzzy dark matter in the center, creating what the researchers named a fermion-boson star, in reference to the two kinds of matter that mixed to form the central object. This star was totally unlike our typical conception of one. It would be gigantic — up to 10,000 light-years across — and almost entirely invisible, except for the subtle glow of the gas spread throughout it.

However, the researchers pointed out that this would serve as the ideal representation of a galactic core, which contains higher — but not too high — densities of normal matter, thereby confirming a key prediction of the fuzzy dark matter model.

The next step is to build even more sophisticated models to explore what these "stars" might look like so that astronomers can compare the predictions to real-world observations.

A hidden family of "ghost particles" may be responsible for all the dark matter in the universe — and the reason that there is any matter at all, a recent preprint study suggests.

One of the most puzzling questions in modern cosmology is why the universe is filled with matter in the first place. The problem is that almost all fundamental particle reactions produce exact numbers of matter and antimatter particles, which then go on to annihilate each other in flashes of energy. But the universe has an abundance of matter and very little antimatter. So why didn't everything just disappear in the early universe?

The problem is known as baryogenesis, and the leading hypothesis is that some unknown process led to an imbalance of matter over antimatter in the first moments of the Big Bang. But what could that process have been?

New research suggests that the answer may lie in ghostly little particles known as neutrinos. The research was published Dec. 18 on the preprint server arXiv and has not yet been peer-reviewed.

Related: 32 physics experiments that changed the world

There are three varieties of neutrinos, and they all have bizarre properties. For one, they have just a tiny bit of mass, far smaller than even the mass of electrons. They are also all "left-handed," which means their internal spins orient in only one direction as they travel, unlike all other particles that can orient in both directions.

This has led to speculation that there may be more neutrino varieties out there that we haven't detected yet — the right-handed counterparts to the known neutrinos. That's because interactions between the left- and right-handed varieties of neutrinos could cause them to have mass.

A shattered universe

In their recent paper, the researchers proposed a model in which there are two right-handed neutrino species that have very high masses. The model showed that in the earliest moments of the universe, the left- and right-handed neutrinos were in perfect balance. But as the cosmos expanded and cooled, that balance broke, leading to a breaking of symmetries that caused the left-handed neutrinos to acquire their mass and the right-handed neutrinos to disappear from view.

But the researchers' model found that this cataclysmic shift also had other consequences. For one, because neutrinos interact with other particles, their broken symmetry triggered a chain reaction that threw off the delicate balance between matter and antimatter. Second, the right-handed neutrinos mixed together to create an altogether new particle, dubbed the Majoron. The Majoron is a hypothetical particle that is its own anti-particle, and the researchers' calculations showed that this particle would have been made in abundance in the chaos of the early universe.

The Majoron would then survive as a relic of those ancient times, making up the bulk of the mass of every galaxy but remaining invisible and elusive. In other words, it would be a candidate for dark matter, the mysterious hidden substance that fills the cosmos.

It's an audacious proposal, but a comprehensive one. According to the researchers, a single mechanism could explain the strange properties of neutrinos, the baryogenesis that led to the dominance of matter in the universe, and the appearance of mysterious dark matter.

To date, there has been no experimental evidence for the existence of any right-handed neutrinos, let alone something even more exotic like the Majoron. But the researchers predict that if the Majoron exists, it could be within the detectability range of a number of neutrino experiments, like Super-Kamiokande and Borexino — two underground neutrino detectors based in Japan and Italy, respectively. Only time will tell if one of these experiments will find a new signal that lines up with this hypothesis — but if that happens, we may be on the path to solving a number of cosmological mysteries.

Editor's note: This article was updated on Jan. 11 to correct a spelling error. A previous version of the article called the proposed particle the "Majoran"; the correct name is the "Majoron."

New observations made by the James Webb Space Telescope (JWST) have further cemented one of the most bizarre observations in all of physics — that the universe expanded at different speeds across varying stages of its lifetime.

The conundrum, referred to as the Hubble tension, has fueled a debate among astronomers that could alter or even upend the field altogether.

In 2019, measurements by the Hubble Space Telescope confirmed the problem was real. Then in 2023 and 2024, even more precise measurements from JWST appeared to confirm the discrepancy.

Now, further measurements have used the largest sample of JWST data collected over its first two years in space to further cement the problem. The new physics that could answer the mystery remains unclear but, as the researchers outline in a paper published Dec. 9 in the The Astrophysical Journal, the tension is not going anywhere.

"The more work we do the more it is apparent that the cause is something much more interesting than a telescope flaw. Rather it appears to be a feature in the universe," lead study author and Nobel laureate Adam Riess, professor of physics and astronomy at Johns Hopkins University, told Live Science. "[The] next steps are many. More data on many fronts and new ideas are needed."

Related: After 2 years in space, the James Webb telescope has broken cosmology. Can it be fixed?

There are two gold-standard methods for figuring out the Hubble constant, the value that quantifies the speed of the universe's expansion. The first is taken by measuring tiny fluctuations in the cosmic microwave background — an ancient snapshot of the universe's first light produced just 380,000 years after the Big Bang.

After mapping out this microwave hiss using the European Space Agency's Planck satellite, cosmologists inferred a Hubble constant of roughly 46,200 mph per million light-years, or roughly 67 kilometers per second per megaparsec (km/s/Mpc). This, alongside other measurements of the early universe, aligned with theoretical predictions.

The second method operates at closer distances and in the universe's later life using pulsating stars called Cepheid variables. Cepheid stars are slowly dying, and their outer layers of helium gas grow and shrink as they absorb and release the star's radiation, making them periodically flicker like distant signal lamps.

As Cepheids get brighter, they pulsate more slowly, enabling astronomers to measure the stars' intrinsic brightness. By comparing this brightness to their observed brightness, astronomers can chain Cepheids into a "cosmic distance ladder" to peer ever deeper into the universe's past.

With this ladder in place, and after anchoring the Cepheids' brightnesses to explosions from Type Ia supernovae, astronomers can find a precise number for the universe's expansion speed from how the flickering stars' light has been stretched out, or redshifted. The Hubble constant returned by this method is around 73 km/s/Mpc: a value far outside of the error range of the Planck measurements.

Related: 'It could be profound': How astronomer Wendy Freedman is trying to fix the universe

Astronomers have offered various explanations for the cause of this disagreement, with some attempting to tease out the possibility of systematic error within the results. Meanwhile, Riess and his team have been cementing the tension with increasingly precise and wider-encompassing studies.

This new study is yet another link in this chain. Covering roughly a third of the sample size of the 2019 Hubble study, the new analysis used JWST to measure the sample's Cepheid distances to within 2% accuracy — a big improvement on Hubble's precision of 8-9%.

Cross-checking these results with other distance-measuring stars such as carbon rich stars and bright red giants returned a value of 72.6 km/s/Mpc, making it nearly identical to Hubble's original measurement.

Exactly what could be causing the strange mismatch is unclear ("I wish I knew," Riess told Live Science). But speculation is rife among astronomers.

One possibility is "something missing in our understanding of the early universe, such as a new component of matter — early dark energy [the mysterious phenomenon driving cosmic expansion] — that gave the universe an unexpected kick after the big bang," Marc Kamionkowski, a cosmologist at Johns Hopkins University who helped calculate the Hubble constant and who was not involved in the study, said in a statement. "And there are other ideas, like funny dark matter properties, exotic particles, changing electron mass, or primordial magnetic fields that may do the trick. Theorists have license to get pretty creative."

Minuscule black holes that can hollow out entire planets could be tunneling through objects on Earth, according to a wild new theoretical study. These hypothetical space-time missiles may be leaving microscopic traces of their passage in everyday objects and even our own bodies, the new research suggests.

Formed in the fiery afterglow of the Big Bang, primordial black holes (PBHs) are one of the candidates for dark matter — the mysterious, invisible substance that makes up 85% of the universe's matter.

Yet the extreme tininess of these hypothetical black holes means that, so far, no evidence for them has been found. Now, a team of physicists, writing in the December issue of the journal Physics of the Dark Universe, has proposed a new place to look for clues — everywhere.

"The chances of finding these signatures are small, but searching for them would not require much resources and the potential payoff, the first evidence of a primordial black hole, would be immense," co-author, Dejan Stojkovic, a professor of physics at the University at Buffalo, said in a statement. "We have to think outside of the box because what has been done to find primordial black holes previously hasn't worked."

Black holes as we know them are born from the gravitational collapse of dying stars or gas clouds. Throughout their lifespan, they can gorge on matter and merge with other black holes to swell to monstrous, supermassive scales.

Related: Scientists may have finally solved the problem of the universe's 'missing' black holes

But primordial black holes are different beasts altogether. Formed from dense pockets of subatomic matter in the first few fractions of a second of the universe's life, the hypothetical entities are as heavy as mountains yet barely larger than a hydrogen atom. This makes proving (or disproving) their existence an incredibly difficult task.

To help in the hunt for these extreme entities, the physicists behind the new study performed a number of calculations to constrain what astronomers should be looking for when they search for the objects. One idea they propose is to look for planets and asteroids that captured the mini black holes and became hollowed-out by them.

"If the object has a liquid central core, then a captured PBH can absorb the liquid core, whose density is higher than the density of the outer solid layer," Stojkovic says. After sucking up the insides of a planetoid, the tiny black holes could then escape from the planetary shell after an impact from another space rock jolts it free.

Then, if the hollowed-out rock is relatively small — roughly one-tenth the size of Earth — it could survive as a shell for astronomers to spot.

"If it is any bigger than that, it's going to collapse," Stojkovic said.

But we may not even need to look into the skies to find evidence of the mini monsters. The researchers also calculated what would happen if a primordial black hole travelling at high speed were to zip through an object here on Earth. They found that a PBH with a mass of 1.12 tons (1,019 kilograms) would bore a tunnel 700 times smaller than the width of a human hair if an unlucky object got in its way.

Thankfully, that's unlikely to cause any noticeable damage to human tissue, the researchers noted.

"If a projectile is moving through a medium faster than the speed of sound, the medium's molecular structure doesn't have time to respond," Stojkovic says. "Throw a rock through a window, it's likely going to shatter. Shoot a window with a gun, it's likely to just leave a hole."

The odds of this happening to anyone or anything are also incredibly slim — with the researchers' calculations showing the probability of a primordial black hole passing through a billion-year-old boulder to be 0.0001%. This means that, if we are to search for evidence of PBHs, we should look in materials and buildings that are already very old, the scientists noted.

Such efforts to find objects that haven't even been proven to exist could easily be dismissed, but the researchers say that unconventional thinking could be essential in tackling unresolved problems that have plagued physics for decades — the nature of dark matter being just one of them.

"The smartest people on the planet have been working on these problems for 80 years and have not solved them yet," Stojkovic said. "We don't need a straightforward extension of the existing models. We probably need a completely new framework altogether."

Astronomers have analyzed the largest map of the universe — and found that Einstein was right yet again about gravity, according to a series of new studies.

The analysis, which looked at nearly 6 million galaxies and quasars spanning 11 billion years of cosmic time, found that even at colossal scales the force of gravity behaves as predicted by Albert Einstein's theory of general relativity.

The result validates cosmologists' leading theory of the universe and appears to limit alternative theories of gravity, the researchers said. Where the results leave room for new explanations to strange discrepancies in the model, such as the universe's divergent expansion rates at different stages of its life, remains unclear. The researchers published their findings today (Nov. 19) in several papers on the preprint server arXiv and will present them in January at a meeting of the American Astronomical Society in National Harbor, Maryland.

"General relativity has been very well tested at the scale of solar systems, but we also needed to test that our assumption works at much larger scales," Pauline Zarrouk, a cosmologist at the French National Centre for Scientific Research (CNRS) who co-led the analysis, said in a statement. "Studying the rate at which galaxies formed lets us directly test our theories and, so far, we're lining up with what general relativity predicts at cosmological scales."

Cosmologists have long debated the behavior of gravity at large distances. The predominant theory, called the lambda cold dark matter model, builds out from Einstein's theory to offer the most comprehensive view of a wide range of astronomical phenomena.

Related: Researchers spot rare 'triple-ring' galaxy that defies explanation

But doubts about some elements within the model, such as dark matter and dark energy — two mysterious entities that do not interact with light but account for a majority of the mass and energy in the universe — along with the model's inability to predict some observations, have led rival factions to champion alternative explanations.

One of these is modified Newtonian dynamics (MOND), which proposes that for gravitational pulls 10 trillion times smaller than those felt on Earth's surface, such as the tugs between distant galaxies, Newton's laws (which general relativity builds upon) break down and must be replaced by other equations.

To search for clues on how gravity behaves at large scales, the researchers turned to data from the first year of the Dark Energy Spectroscopic Instrument (DESI) mounted on the Nicholas U. Mayall 4-meter Telescope in Arizona, which pinpoints the monthly positions of millions of galaxies to study how the universe expanded up to the present day.

The scientists conducted a "full-shape analysis" that made a precise measurement of the growth of galactic structures over time. It revealed that, while dark energy could be evolving over time, the universe's structure closely matches predictions made by Einstein's theory.

"This is the first time that DESI has looked at the growth of cosmic structure," Dragan Huterer, a professor of theoretical cosmology and astrophysics at the University of Michigan and the co-lead of DESI's group interpreting the cosmological data, said in the statement. "We're showing a tremendous new ability to probe modified gravity and improve constraints on models of dark energy. And it's only the tip of the iceberg."

It's too early to say exactly what this means for our overall view of the cosmos, but the next two years of DESI's collected data is set to be released in spring 2025. The experiment, which is now in its fourth of five years, will collect data from around 40 million galaxies and quasars by the time it ends. If the answers are out there, we may not have to wait too long to find them.

Astronomers using the James Webb Space Telescope (JWST) have found that some of the universe's oldest galaxies are much brighter and heavier than scientists thought. The finding could lend credibility to an alternative theory to dark matter.

The standard model of galaxy formation predicts that only dim light should be seen from the primitive galaxies that took shape in the first billion years after the Big Bang. The unusually large and bright galaxies detected by JWST bolster predictions made by a rival theory known as modified Newtonian dynamics (MOND). The researchers published their findings Nov. 12 in The Astrophysical Journal.

"What the theory of dark matter predicted is not what we see," study lead author Stacy McGaugh, an astrophysicist at Case Western Reserve University in Ohio, said in a statement. "The bottom line is, 'I told you so.' I was raised to think that saying that was rude, but that's the whole point of the scientific method: Make predictions and then check which come true."

MOND proposes that for gravitational pulls 10 trillion times smaller than those felt on Earth's surface, such as the tugs felt between distant galaxies, Newton's laws break down and must be replaced by other equations. First proposed by Israeli physicist Mordehai Milgrom in 1982, the theory first emerged as an attempt to explain the faster-than-expected rotations seen around the outskirts of distant galaxies.

Related: Researchers spot rare 'triple-ring' galaxy that defies explanation

MOND has had a number of successes, helping to unearth unexpected laws dictating how galaxies move through space. Yet the theory remains widely rejected by astronomers, who tend to favor cold dark matter theories, because it has yet to explain a wide range of cosmological phenomena. On the other hand, dark matter theories can explain a lot of observations, but they fail to do so for those accurately predicted by MOND.

To search for clues that could break the deadlock, the astronomers pored over data collected by JWST, capturing the dim signals of some of the earliest galaxies in the universe. According to their study, these ancient galaxies had grown significantly bigger and brighter than conventional dark matter models forecast, but they are exactly in line with the predictions made by MOND.

Exactly what could be causing the discrepancy remains an exciting mystery. It's possible that the additional brightness stems from supermassive black holes that are growing significantly faster than expected, but that idea presents problems of its own.

"We find ourselves caught between two very different theories that seem irreconcilable despite applying to closely related yet incommensurate lines of evidence," the astronomers wrote in the paper. "The simple force law hypothesized by MOND has made enough successful a priori predictions that it cannot be an accident: it must be telling us something. What that is remains as mysterious as the composition of dark matter."

The James Webb Space Telescope (JWST) has spotted a trio of gigantic "red monster" galaxies in the early universe, and they could rewrite our understanding of how stars and galaxies first formed.

The enormous galaxies — each 100 billion times the mass of our sun and nearly as massive as the Milky Way — are more than 12.8 billion years old, having formed within a billion years of the Big Bang.

This means that the stars within these galaxies coalesced at a bafflingly fast rate; so fast, they challenge existing models of how galaxies form. The researchers published their findings Nov. 13 in the journal Nature.

"Finding three such massive beasts among the sample poses a tantalising puzzle," study co-author Stijn Wuyts, a professor of astronomy at the University of Bath in the U.K., said in a statement. "Many processes in galaxy evolution have a tendency to introduce a rate-limiting step in how efficiently gas can convert into stars, yet somehow these Red Monsters appear to have swiftly evaded most of these hurdles."

The conventional view among astronomers is that galaxies form within gigantic halos of dark matter, whose powerful gravity sucks ordinary matter such as gas and dust inwards before compressing it to form stars.

Related: James Webb Space Telescope is 'science and magic rolled together,' says iconic astronomer Maggie Aderin-Pocock

Typically, this is seen as a fairly inefficient process, with just 20% of the infalling gas ending up as stars. The discovery of the red monsters confounds this view, with as much of 80% of their gas seemingly converted into bright young stars.

"These results indicate that galaxies in the early Universe could form stars with unexpected efficiency," study lead author Mengyuan Xiao, a researcher at the University of Geneva, said in the statement. "As we study these galaxies in more depth, they will offer new insights into the conditions that shaped the Universe's earliest epochs. The Red Monsters are just the beginning of a new era in our exploration of the early Universe."

The red monsters, which get their nickname from their distinctive red glow, were spotted using the JWST's Near Infrared Camera (NIRCam), a spectrograph that studies distant light by splitting it into its constituent parts. The JWST's infrared capabilities enable it to peer deeper and into more dust-obscured parts of the early universe than other telescopes.

The researchers' next steps will be to make further observations of the red monsters using both the JWST and Chile's Atacama Large Millimeter Array (ALMA) telescope. The discoveries also raise questions for astrophysicists working on models of how early galaxies evolved, who may have to consider unique processes that enabled giant galaxies to grow with such efficient star formation.

"Already in its first few years of operation, JWST has thrown us a couple of curveballs," Wuyts said. "In more ways than one, it has shown us that some galaxies mature rapidly during the first chapters of cosmic history."

The first piece of what will one day be the largest-ever 3D map of the universe has been revealed, and it's crammed with 14 million galaxies.

The snapshot was taken by the European Space Agency's (ESA) Euclid space telescope. Launched on July 1, 2023, Euclid was designed to compile wide-lens images to help scientists hunt for two of the universe's most mysterious components: dark matter and dark energy.

The stunning new image is a mosaic of 208 gigapixels, representing just a fraction of a percent of the sky. By capturing hundreds of images like this one, the space telescope will eventually catalog one-third of the entire night sky and image more than a billion galaxies that are up to 10 billion years old, according to ESA.

"This stunning image is the first piece of a map that in six years will reveal more than one third of the sky," Valeria Pettorino, a Euclid project scientist at ESA, said in a statement. "This is just 1% of the map, and yet it is full of a variety of sources that will help scientists discover new ways to describe the Universe."

Related: Mysterious 'Green Monster' lurking in James Webb photo of supernova remnant is finally explained

The released image is a mosaic of 260 observations collected across two weeks between March and April 2024. It represents a 132-square-degree sweep of the southern sky that is more than 500 times the area of the full moon.

The map, which contains 100 million sources of light, is just one small piece in the cosmic jigsaw puzzle being assembled by Euclid. Upon completion, it will enable scientists to probe the mysteries of dark matter and dark energy.

Researchers think dark matter and dark energy together make up about 95% of the universe. But they do not interact with light, so they can't be detected directly.

Instead, scientists study the mysterious components by observing the way they interact with the visible universe around them: Dark matter can be seen by observing its gravitational warping effects on galaxies, and dark energy is evident in the force propelling the universe's runaway expansion.

So far, 12% of Euclid's mission has been completed. Further releases, including a preview of Euclid's Deep Field areas, are planned for release in March 2025, and the mission's first year of cosmology data will appear in 2026.

Dark matter could produce faint flashes of light when interacting with tiny black holes, new theoretical research suggests. These flashes could one day help scientists locate and study the mysterious matter, which has so far remained invisible.

Dark matter makes up the vast majority of the mass of almost every galaxy in the universe, but its exact nature still eludes scientists. It has gravity, but doesn’t interact with light or produce light of its own, so we only have circumstantial evidence of its existence through its gravitational interactions with everything else.

In these circumstances, researchers are desperate to cook up any scenario that might make dark matter more visible. So why not use black holes? It sounds like a ridiculous question: How could black holes, which devour any light that gets too close to them, make dark matter shine? But researchers have put together a scenario that might make it possible. They reported their findings Sept. 20 in the preprint database arXiv. (The findings haven't been peer-reviewed).

The researchers assume that dark matter can, in principle, interact with regular matter (and produce light in the process), but, for some reason, normally doesn't. Perhaps the interaction requires a certain amount of energy that simply isn’t available or is prohibited without a mediator particle doing the work. Black holes could provide the avenue needed to overcome these barriers and get the dark matter to light up.

But not just any black hole will do the trick, only ultra-tiny primordial black holes. These black holes aren’t the leftovers of giant stars but the remnants of the chaotic eras of the extremely early universe, where matter and energy spontaneously compressed to make them. Primordial black holes were first hypothesized by Stephen Hawking, but observations have so far failed to find any. If they do exist, they are extremely uncommon.

Like all black holes, primordial black holes would evaporate Hawking radiation, a strange quantum effect discovered by Stephen Hawking in which virtual particles pop up near a black hole's edge and some are able to escape. The smaller the black hole, the more radiation it emits.so primordial black holes roughly the mass of an asteroid would be emitting plenty of radiation in the present-day universe.

This radiation emitted by black holes isn’t just packets of light, or photons. It’s almost every kind of particle, including dark matter particles. As the primordial black holes decay, they emit dark matter particles that then energize any ambient dark matter particles in their vicinity, triggering a cascade that can briefly release visible light.

The researchers predict that these signals will typically be in the form of gamma ray flashes. They are far too weak for current experiments to detect, but future observatories, like NASA’s proposed All-sky Medium Energy Gamma-ray Observatory eXplorer (AMEGO-X), might have the sensitivity and resolution needed to find these sorts of signals.

The James Webb Space Telescope (JWST) is the largest and most powerful space telescope built to date. Since it was launched in December 2021 it has provided groundbreaking insights. These include discovering the earliest and most distant known galaxies, which existed just 300 million years after the Big Bang.

Distant objects are also very ancient because it takes a long time for the light from these objects to reach telescopes. JWST has now found a number of these very early galaxies. We're effectively looking back in time at these objects, seeing them as they looked shortly after the birth of the universe.

These observations from JWST agree with our current understanding of cosmology — the scientific discipline that aims to explain the universe — and of galaxy formation. But they also reveal aspects we didn't expect. Many of these early galaxies shine much more brightly than we would expect given that they existed just a short time after the Big Bang.

Brighter galaxies are thought to have more stars and more mass. It was thought that much more time was needed for this level of star formation to take place. These galaxies also have actively growing black holes at their centres — a sign that these objects matured quickly after the Big Bang. So how can we explain these surprising findings? Do they break our ideas of cosmology or require a change to the age of the universe?

Scientists have been able to study these early galaxies by combining JWST's detailed images with its powerful capabilities for spectroscopy. Spectroscopy is a method for interpreting the electromagnetic radiation that's emitted or absorbed by objects in space. This in turn can tell you about the properties of an object.

Our understanding of cosmology and galaxy formation rests on a few fundamental ideas. One of these is the cosmological principle, which states that, on a large scale, the universe is homogeneous (the same everywhere) and isotropic (the same in all directions). Combined with Einstein's theory of general relativity, this principle allows us to connect the evolution of the universe —- how it expands or contracts —- to its energy and mass content.

Related: The James Webb telescope has brought cosmology to a tipping point. Will it soon reveal new physics?

The standard cosmological model, known as the "Hot Big Bang" theory, includes three main components, or ingredients. One is the ordinary matter that we can see with our eyes in galaxies, stars and planets. A second ingredient is cold dark matter (CDM), slow-moving matter particles that do not emit, absorb or reflect light.

The third component is what's known the cosmological constant (Λ, or lambda). This is linked to something called dark energy and is a way of explaining the fact that the expansion of the universe is accelerating. Together, these components form what is called the ΛCDM model of cosmology.

Dark energy makes up about 68% of the total energy content of today's universe.

Despite not being directly observable with scientific instruments, dark matter is thought to make up most of the matter in the cosmos and comprises about 27% of the universe's total mass and energy content.

While dark matter and dark energy remain mysterious, the ΛCDM model of cosmology is supported by a wide range of detailed observations. These include the measurement of the universe's expansion, the cosmic microwave background, or CMB (the "afterglow" of the Big Bang) and the development of galaxies and their large-scale distribution — for example, the way that galaxies cluster together.

The ΛCDM model lays the groundwork for our understanding of how galaxies form and evolve. For example, the CMB, which was emitted about 380,000 years after the Big Bang, provides a snapshot of early fluctuations in density that occurred in the early universe. These fluctuations, particularly in dark matter, eventually developed into the structures we observe today, such as galaxies and stars.

How stars form

Galaxy formation consists of complex processes influenced by numerous different physical phenomena. Some of these mechanisms are not fully understood, such as what processes govern how gas in galaxies cools and condenses to form stars.

The effects of supernovae, stellar winds and black holes that emit significant amounts of energy (sometimes called active galactic nuclei, or AGN) can all heat or expel gas from galaxies. This in turn can boost or curtail star formation and therefore influence the growth of galaxies.

The efficiency and scale of these "feedback processes", as well as their cumulative impact over time, are poorly understood. They are a significant source of uncertainty in mathematical models, or simulations, of galaxy formation.

Significant advances in complex numerical simulations of galaxy formation have been made over the past ten years. Insights and hints can still be gained from simpler simulations and models that relate star formation to the evolution of dark matter halos. These halos are massive, invisible structures made from dark matter that effectively anchor galaxies within them.

One of the simpler models of galaxy formation assumes that the rate at which stars form in a galaxy is directly tied to gas flowing into those galaxies. This model also proposes that the star formation rate in a galaxy is proportional to the rate at which dark matter halos grow. It assumes a fixed efficiency at converting gas into stars, regardless of cosmic time.

This "constant star formation efficiency" model is consistent with star formation increasing dramatically in the first billion years after the Big Bang. The rapid growth of dark matter halos during this period would have provided the necessary conditions for galaxies to form stars efficiently. Despite its simplicity, this model has successfully predicted a wide range of real observations, including the overall rate of star formation across cosmic time.

Secrets of the first galaxies

JWST has ushered in a new era of discovery. With its advanced instruments, the space telescope can capture both detailed images and high resolution spectra — charts showing the intensity of electromagnetic radiation emitted or absorbed by objects in the sky. For JWST, these spectra are in the near infrared region of the electromagnetic spectrum. Studying this region is crucial for observing early galaxies whose optical light has turned into near infrared (or "redshifted") as the universe has expanded.

Redshift describes how the wavelengths of light from galaxies become stretched as they travel. The more distant a galaxy is, the greater its redshift.

Over the past two years, JWST has identified and characterized galaxies at redshifts with values of between ten and 15. These galaxies, which formed around 200-500 million years after the Big Bang, are relatively small for galaxies (about 100 parsecs, or 3 quadrillion kilometres, across). They each consist of around 100 million stars, and form new stars at a rate of about one sun-like star per year.

While this does not sound very impressive, it implies that these systems double their content of stars within only 100 million years. For comparison, our own Milky Way galaxy takes about 25 billion years to double its stellar mass.

Early galaxy formation

The surprising findings from JWST of bright galaxies at high redshifts, or distances, could imply that these galaxies matured faster than expected after the Big Bang. This is important because it would challenge existing models of galaxy formation. The constant star-formation efficiency model described above, while effective at explaining much of what we see, struggles to account for the large number of bright and distant galaxies observed with a redshift of more than ten with a redshift of more than ten.

To address this, scientists are exploring various possibilities. These include changes to their theories of how efficiently gas is converted into stars over time. They are also reconsidering the relative importance of the feedback processes — how phenomena such as supernovae and black holes also help regulate star formation.

Some theories suggest that star formation in the early universe may have been more intense or "bursty" than previously thought, leading to the rapid growth of these early galaxies and their apparent brightness.

Others propose that different factors, such as lower amounts of galactic dust, a top-heavy distribution of star masses, or contributions from phenomena such as active black holes, could be responsible for the unexpected brightness of these early galaxies.

These explanations invoke changes to galaxy formation physics in order to explain JWST's findings. But scientists have also been considering modifications to broad cosmological theories. For example, the abundance of early, bright galaxies could be partly explained by a change to something called the matter power spectrum. This is a way to describe density differences in the universe.

One possible mechanism for achieving this change in the matter power spectrum is a theoretical phenomenon called "early dark energy". This is the idea that a new cosmological energy source with similarities to dark energy may have existed at early times, at a redshift of 3,000. This is before the CMB was emitted and just 380,000 years after the Big Bang.

This early dark energy would have decayed rapidly after the stage of the universe's evolution known as recombination. Intriguingly, early dark energy could also alleviate the Hubble tension — a discrepancy between different estimates of the universe's age.

One paper published in 2023 suggested that the galaxy findings from JWST required scientists to stretch the age of the universe by several billion years.

However, other phenomena could account for the bright galaxies. Before JWST's observations are used to invoke changes to broad ideas of cosmology, a more detailed understanding of the physical processes in galaxies is essential.

The current record holder for the most distant galaxy — identified by JWST — is called JADES-GS-z14-0. The data gathered so far indicate that these galaxies have a large diversity of different properties.

3D visualisation of galaxies observed by the JWST, including JADES-GS-z14-0.

Some galaxies show signs of hosting black holes that are emitting energy, while others seem to be consistent with hosting young, dust-free populations of stars. Because these galaxies are faint and observing them is expensive (it takes exposure times of many hours), only 20 galaxies for which the redshift is more than ten have been observed with spectroscopy to date, and it will take years to build a statistical sample.

A different angle of attack could be observations of galaxies at later cosmic times, when the universe was 1 billion to 2 billion years old (redshifts of between three and nine). JWST's capabilities give researchers access to crucial indicators from stars and gas in these objects that can be used to constrain the overall history of galaxy formation.

Breaking the universe?

In the first year of JWST's operation, it was claimed that some of the earliest galaxies had extremely high stellar masses (the masses of stars contained within them) and a change in cosmology was needed to accommodate bright galaxies that existed in the very early universe. They were even dubbed "universe-breaker" galaxies.

Soon after, it was clear that these galaxies do not break the universe, but their properties can be explained by a range of different phenomena. Better observational data showed that the distances to some of the objects were overestimated (which led to an overestimation of their stellar masses).

The emission of light from these galaxies can be powered by sources other than stars, such as accreting black holes. Assumptions in models or simulations can also lead to biases in the total mass of stars in these galaxies.

As JWST continues its mission, it will help scientists refine their models and answer some of the most fundamental questions about our cosmic origins. It should unlock even more secrets about the universe's earliest days, including the puzzle of these bright, distant galaxies.

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

Maggie Aderin-Pocock never imagined she'd become one of the United Kingdom's most famous scientists. Best known for co-hosting the BBC's astronomy TV program "The Sky at Night," the space scientist and broadcaster rose from unlikely circumstances to pursue her dreams.

Growing up with dyslexia in government housing in London, Aderin-Pocock went on to study physics and later mechanical engineering at Imperial College London. She then worked on space technology projects that include satellite monitoring of climate change and a key scientific instrument aboard the James Webb Space Telescope (JWST) called the Near-infrared spectrograph (NIRSpec), which measures the light from distant cosmic objects to discover the elements and molecules they’re made of.

Now, Aderin-Pocock has written a new book on the telescope, Webb's Universe: The Space Telescope Images That Reveal Our Cosmic History, that she hopes will encourage more children to enter careers in science, technology, engineering and mathematics (STEM). Live Science spoke with her at the Royal Institution in London to discuss the iconic telescope, her work, and inspiring a new generation of scientists.

Ben Turner: Do you remember the moment you knew you wanted to study space for a living? Was it even one moment of realization, or a slow burn?

Maggie Aderin-Pocock: I can't remember a time when I wasn't interested in space, and I think that's because I was born in 1968. The moon landing was in 1969, so I was brought up in that hubbub of excitement where everything was about going to the moon and people exploring the moon — so that was the baseline.

I went to 13 different schools when I was growing up, and four different primary schools, so my education was quite broken up. I say that to some kids and they look at me in horror: "How naughty were you?!" Because my parents broke up when I was about four, sometimes I was with my mum, sometimes with my dad, and that's why I went to lots of different schools.

I felt quite disenfranchised from school. Although working in space and in science was my dream, I remember telling one teacher that I wanted to be a space scientist and they looked at me and said: "Why don't you go into nursing?" So I kept the dream close to my chest, and it was only after university that I started thinking it was a possibility.

Related: James Webb telescope watches ancient supernova replay 3 times — and confirms something is seriously wrong in our understanding of the universe

BT: Let's talk about your work. We've had a number of telescopes which have studied the cosmos in amazing detail. What's so exciting about the JWST?

MAP: Yes, we've had amazing telescopes like Hubble — that's still working after more than 30 years out there. Hubble answered many questions, such as the scale of the universe, with the Hubble Deep Field. It looked at what we thought was empty space for 10 whole days, a really long exposure, and found that it was teeming with galaxies from the early universe.

That's what Hubble gave us, but we wanted to explore the universe in a different way. The James Webb telescope is different from Hubble and many of the other telescopes because it's an infrared telescope — it picks up heat energy. This is why it sits 1.5 million kilometers [0.9 million miles] away from Earth, looking away from the sun and the Earth into deep, dark space.

Infrared light can penetrate clouds and dust and debris which visible light cannot. And with its very large telescope mirror, [JWST] gives us high resolution. Resolution is the key, because with good resolution, it means that two objects that in a smaller telescope would look like a fuzzy blob appear as two distinct objects. So you get a better image quality of the universe.

BT: So why is infrared penetration important? What can we see using infrared that we couldn't with visible light?

MAP: Young stars are born in clouds of dust and gas called nebulae, and infrared light can pass through that dust and gas where visible light would be impeded by it.

Also, the universe is expanding after the Big Bang. That means that wavelengths of light get elongated, and when they get stretched out they go from the visible to infrared light. So when you're looking back to the early universe, because of this universal expansion, looking at infrared light means you can go closer to the beginning of the universe. It enables us to see things further back in time than Hubble was ever able to do.

BT: You had some personal involvement with the JWST, what was it?

So I always need to put a caveat in, because I was one of 10,000 scientists across the world that worked on James Webb — many scientists can claim that they worked on James Webb. But yes, I was one of them, and I worked on an instrument called NIRSpec.

James Webb is a space telescope, it has a heat shield, gray sheets that protect it from infrared radiation coming from the sun and Earth. It also has a mirror, the light gathering power of the telescope. On board, there are four instruments and NIRSpec is one of them.

I've worked on a number of different spectrometers, on Earth and in space. What a spectrometer [like NIRSpec] does is it takes the light gathered by the telescope and then stretches that light into its component colors, it's like making a rainbow in the lab.

Spectrometers produce a thing called absorption bands, and we can analyze different elements or molecules being emitted by astronomical bodies. It enables you to do remote chemistry by studying that spectrum. It gives us all sorts of information about galaxies of stars and we can use that to get a better understanding of what's going on.

BT: And spectrometry can also be used for studying exoplanets as well, right?

MAP: Yes! Often by using something called the transit method. When a planet passes in front of a star it dims by a certain amount, but in some cases a tiny fraction of that starlight can pass through the atmosphere of the planet. By analyzing that starlight using spectroscopy, we can work out what chemicals are in the atmosphere of a planet trillions of kilometers away. It's science and magic rolled together.

BT: I guess it is just a modern form of what magic was.

MAP: I was saying this in an interview earlier — to me, science is just magic that we haven't explained yet.

BT: Your book is jammed full of stunning images alongside beautiful descriptions of them. I know this is probably an impossible question, but if you had to pick any favorite images, which would they be?

MAP: I was looking at the book earlier, and one would have to be the Pillars of Creation. It's when you hear of the scale of it, our entire solar system can fit inside those pillars. It's hard to conceive how big and glorious they are.

They're also something that we've looked at through time. Since we've had photography, we've had grainy black and white pictures of the Pillars of Creation. Then, when Hubble went up, it took images in visible light. Now, we're looking at the infrared version. It's like tripping the light fantastic — if you look at different parts of the electromagnetic spectrum, you can see different aspects. It's a region of space where young stars are born, and by studying it using different types of light you can understand it in different ways.

BT: Every time a big telescope debuts we're reminded of the importance of astronomy. It's a field that has played a central role in human history for thousands of years, being essential for things like navigation and agriculture. How does it affect our lives in the modern day?

MAP: I work as a space scientist, I've worked on the James Webb Space Telescope, but most of the work I do is on observational satellites. These help us to understand climate change and disasters happening on Earth.

But people don't say why do we study history, or why do we do philosophy or art? One day we might get an answer to whether we're alone in the universe. That's a question that's fundamental in every culture across the world. And we're using the means we have to try to discover this.

Now in some ways, I think looking out there is still useful because we're going to leave our planet in about 4 billion years: when the sun expands into a red giant and gobbles up Mercury, Venus and the Earth. I think our destiny is out in space, so getting a better understanding of it, how it works, what dark matter is, how we tackle radiation, is all useful in and of itself.

But putting all of that aside, just having that knowledge is important. Growing up, I thought that astronomy was done by white guys in togas — it was the Greeks, it was the Romans, these are the guys that did astronomy. But that's getting it totally wrong, every culture has looked up and wondered. I think it's something fundamental in all of us, and so it makes sense that we continue doing it today.

BT: Do you have any lesser known examples of ancient cultures' astronomical observations to mind?

MAP: A few years ago I wrote a book about stargazing. We talk about the 88 constellations of the night sky; that's very Greek- and Roman-influenced.

But if you go down to places like Australia or Chile in South America, the nights are so clear that aboriginal cultures looked up into clouds of dust embedded in the Milky Way galaxies and made constellations out of those. There's one called the emu; you have to tilt your head a bit but you can see it: it's an emu. It just shows that, depending on your perspective, what you're seeing will influence how you'll interpret the stars.

The other thing is that the oldest stone circle isn't even Stonehenge, and it actually sits on African soil. It's called Nabta Playa in Namibia and it's about 7,000 years old, so 2,000 years older than Stonehenge. If we go further back, in Aberdeenshire, Scotland, [in Warren Field] there are a series of pits and each one corresponds to the phase of the moon — these are 10,000 years old. And yet they dug them because astronomy was important to them.

BT: You spoke earlier about the social barriers you had to overcome to make your career happen. What advice would you give to young people, especially those from disadvantaged backgrounds, who are interested in becoming scientists — or achieving their dreams generally?

MAP: When I go out and speak to kids, I tell them to reach for the stars. No matter what your stars are — my stars actually happen to be stars — find where your passion lies. Because if you work somewhere that you love, it's not really work, it's joy.

I would also tell them to have a big, crazy dream. Success isn't about not failing, I've fallen over a number of times: things have gone wrong; I haven't got the right job I wanted; I haven't got the exam results I wanted. But because I had this big, crazy dream of getting into space, it means that I picked myself up, I lamented the fact that I failed, but then I went on.

BT: Let's say someone reads this and is inspired to give astronomy a go, what are the kinds of questions they could be answering with their future work?

MAP: I think whether we're alone in the universe.

We can now find exoplanets going around distant stars and look at their atmospheres, so in the future we'll be sending probes out there.

At the moment it seems like a crazy dream scenario, traveling from our solar system to the one next door [Proxima Centauri], which is 4.28 light-years away. That's 40 trillion kilometers [24 trillion miles], a journey that would take 76,000 years traveling at 60 kilometers per second. That's going pretty fast — still 76,000 years!

I'd love it if they found a way to send probes out faster and travel those distances quicker. That and finding ways of getting us out there… I'm throwing that one out to the kids. When you find the solution, come and tell me!

Editor's note: This interview has been edited and condensed for clarity.

For the past few years, a series of controversies have rocked the well-established field of cosmology. In a nutshell, the predictions of the standard model of the universe appear to be at odds with some recent observations.

There are heated debates about whether these observations are biased, or whether the cosmological model, which predicts the structure and evolution of the entire universe, may need a rethink. Some even claim that cosmology is in crisis. Right now, we do not know which side will win. But excitingly, we are on the brink of finding that out.

To be fair, controversies are just the normal course of the scientific method. And over many years, the standard cosmological model has had its share of them. This model suggests the universe is made up of 68.3% "dark energy" (an unknown substance that causes the universe's expansion to accelerate), 26.8% dark matter (an unknown form of matter) and 4.9% ordinary atoms, very precisely measured from the cosmic microwave background — the afterglow of radiation from the Big Bang.

It explains very successfully multitudes of data across both large and small scales of the universe. For example, it can explain things like the distribution of galaxies around us and the amount of helium and deuterium made in the universe's first few minutes. Perhaps most importantly, it can also perfectly explain the cosmic microwave background.

This has led to it gaining the reputation as the "concordance model". But a perfect storm of inconsistent measurements — or "tensions" as they're known as in cosmology — are now questioning the validity of this longstanding model.

Related: Is the James Webb Space Telescope really 'breaking' cosmology?

Uncomfortable tensions

The standard model makes particular assumptions about the nature of dark energy and dark matter. But despite decades of intense observation, we still seem no closer to working out what dark matter and dark energy are made of.

The litmus test is the so-called Hubble tension. This relates to the Hubble constant, which is the rate of expansion of the universe at the present time. When measured in our nearby, local universe, from the distance to pulsating stars in nearby galaxies, called Cepheids, its value is 73 km/s/Mega parsec (Mpc is a unit of measure for distances in intergalactic space). However, when predicted theoretically, the value is 67.4 km/s/Mpc. The difference may not be large (only 8%), but it is statistically significant.

The Hubble tension became known about a decade ago. Back then, it was thought that the observations may have been biased. For example, the Cepheids, although very bright and easy to see, were crowded together with other stars, which could have made them appear even brighter. This could have made the Hubble constant higher by a few percent compared to the model prediction, thus artificially creating a tension.

With the advent of the James Webb Space Telescope (JWST), which can separate the stars individually, it was hoped that we would have an answer to this tension.

Frustratingly, this hasn't yet happened. Astronomers now use two other types of stars besides the Cepheids (known as the Tip of the Red Giant Branch stars (TRGB) and the J-region Asymptotic Giant Branch (JAGB) stars). But while one group has reported values from the JAGB and TRGB stars that are tantalisingly close to the value expected from the cosmological model, another group has claimed that they are still seeing inconsistencies in their observations. Meanwhile, the Cepheids measurements continue to show a Hubble tension.

It's important to note that although these measurements are very precise, they may still be biased by some effects uniquely associated with each type of measurement. This will affect the accuracy of the observations, in a different way for each type of stars. A precise but inaccurate measurement is like trying to have a conversation with a person who is always missing the point. To solve disagreements between conflicting data, we need measurements that are both precise and accurate.

The good news is that the Hubble tension is now a rapidly developing story. Perhaps we will have the answer to it within the next year or so. Improving the accuracy of data, for example by including stars from more far away galaxies, will help sort this out. Similarly, measurements of ripples in spacetime known as gravitational waves will also be able to help us pin down the constant.

This may all vindicate the standard model. Or it may hint that there's something missing from it. Perhaps the nature of dark matter or the way that gravity behaves on specific scales is different to what we believe now. But before discounting the model, one has to marvel at its unmatched precision. It only misses the mark by at most a few percent, while extrapolating over 13 billion years of evolution.

To put it into perspective, even the clockwork motions of planets in the Solar System can only be computed reliably for less than 1 billion years, after which they become unpredictable. The standard cosmological model is an extraordinary machine.

The Hubble tension is not the only trouble for cosmology. Another one, known as the "S8 tension", is also causing trouble, albeit not on the same scale. Here the model has a smoothness problem, by predicting that matter in the universe should be more clustered together than we actually observe — by about 10%. There are various ways to measure the "clumpiness" of matter, for example by analysing the distortions in the light from galaxies, produced by the assumed dark matter intervening along the line of sight.

Currently, there seems to be a consensus in the community that the uncertainties in the observations have to be teased out before ruling out the cosmological model. One possible way to alleviate this tension is to better understand the role of gaseous winds in galaxies, which can push out some of the matter, making it smoother.

Understanding how clumpiness measurements on small scales relate to those on larger scales would help. Observations might also suggest there is a need to change how we model dark matter. For example, if instead of being made entirely of cold, slow moving particles, as the standard model assumes, dark matter could be mixed up with some hot, fast-moving particles. This could slow down the growth of clumpiness at late cosmic times, which would ease the S8 tension.

JWST has highlighted other challenges to the standard model. One of them is that early galaxies appear to be much more massive that expected. Some galaxies may weigh as much as the Milky Way today, even though they formed less than 1 billion years after the Big Bang, suggesting they should be less massive.

However, the implications against the cosmological model are less clear in this case, as there may be other possible explanations for these surprising results. Key to solving this problem is to improve the measurement of stellar masses in galaxies. Rather than measuring them directly, which is not possible, we infer these masses from the light emitted by galaxies.

This step involves some simplifying assumptions, which could translate in overestimating the mass. Recently, it has also been argued that some of the light attributed to stars in these galaxies is generated by powerful black holes. This would imply that these galaxies may not be as massive after all.

Alternative theories

So, where do we stand now? While some tensions may soon be explained by more and better observations, it is not yet clear whether there will be a resolution to all of the challenges battering the cosmological model.

There has been no shortage of theoretical ideas of how to fix the model though — perhaps too many, in the range of a few hundred and counting. That's a perplexing task for any theorist who may wish to explore them all.

The possibilities are many. Perhaps we need to change our assumptions of the nature of dark energy. Perhaps it is a parameter that varies with time, which some recent measurements have suggested. Or maybe we need to add more dark energy to the model to boost the expansion of the universe at early times, or, on the contrary, at late times. Modifying how gravity behaves on large scales of the universe (differently than done in the models called Modified Newtonian Dynamics, or MOND) may also be an option.

So far, however, none of these alternatives can explain the vast array of observations that the standard model can. Even more worrisome, some of them may help with one tension but worsen others.

The door is now open to all sorts of ideas that challenge even the most basic tenets of cosmology. For example, we may need to abandon the assumption that the universe is "homogeneous and isotropic" on very large scales, meaning it looks the same in all directions to all observers and suggesting there are no special points in the universe. Others propose changes to the theory of general relativity.

Some even imagine a trickster universe, which participates with us in the act of observation, or which changes its appearance depending on whether we look at it or not — something we know happens in the quantum world of atoms and particles.

In time, many of these ideas will likely be relegated to the cabinet of curiosities of theorists. But in the meantime, they provide a fertile ground for testing the "new physics".

This is a good thing. The answer to these tensions will no doubt come from more data. In the next few years, a powerful combination of observations from experiments such as JWST, the Dark Energy Spectroscopic Instrument (DESI), the Vera Rubin Observatory and Euclid, among many others, will help us find the long-sought answers.

Tipping point

On one side, more accurate data and a better understanding of the systematic uncertainties in the measurements could return us to the reassuring comfort of the standard model. Out of its past troubles, the model may emerge not only vindicated, but also strengthened, and cosmology will be a science that is both precise and accurate.

But if the balance tips the other way, we will be ushered into uncharted territory, where new physics will have to be discovered. This could lead to a major paradigm shift in cosmology, akin to the discovery of the accelerated expansion of the universe in the late 1990s. But on this path we may have to reckon, once and for all, with the nature of dark energy and dark matter, two of the big unsolved mysteries of the universe.

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

The Big Bang may not have been the beginning of the universe, according to a theory of cosmology that suggests the universe can “bounce” between phases of contraction and expansion. If that theory is true, then it could have profound implications about the nature of the cosmos, including two of its most mysterious components: black holes and dark matter.

With this in mind, a recent study suggests that dark matter could be composed of black holes formed during a transition from the universe's last contraction to the current expansion phase, which occurred before the Big Bang. If this hypothesis holds, the gravitational waves generated during the black hole formation process might be detectable by future gravitational wave observatories, providing a way to confirm this dark matter generation scenario.

Observations of stellar movements in galaxies and the cosmic microwave background — an afterglow of the Big Bang — indicate that about 80% of all matter in the universe is dark matter, a substance that doesn't reflect, absorb or emit light. Despite its abundance, scientists have not yet identified what dark matter is made of.

In the new study, researchers explored a scenario where dark matter consists of primordial black holes formed from density fluctuations that occurred during the universe's last contraction phase, not long before the period of expansion that we observe now. They published their findings in June in the Journal of Cosmology and Astroparticle Physics.

The bouncing cosmos

The traditional cosmological view of the universe suggests that it started from a singularity, followed by a short period of extremely rapid expansion, called inflation. However, the authors behind the new study analyzed a more exotic theory, known as non-singular matter bouncing cosmology, which posits that the universe first underwent a contraction phase. This phase ended with a rebound due to the increasing density of matter, leading to the Big Bang and the accelerated expansion we observe today.

Related: The universe could stop expanding 'remarkably soon', study suggests

In this bouncing cosmology, the universe contracted to a size about 50 orders of magnitude smaller than it is today. After the rebound, photons and other particles were born, marking the Big Bang. Near the rebound, the matter density was so high that small black holes formed from quantum fluctuations in the matter’s density, making them viable candidates for dark matter.

"Small primordial black holes can be produced during the very early stages of the universe, and if they are not too small, their decay due to Hawking radiation [a hypothetical phenomenon of black holes emitting particles due to quantum effects] will not be efficient enough to get rid of them, so they would still be around now," Patrick Peter, director of research at the French National Centre for Scientific Research (CNRS), who was not involved in the study, told Live Science in an email. "Weighing more or less the mass of an asteroid, they could contribute to dark matter, or even solve this issue altogether."

The scientists' calculations show that this universe mode's properties, such as the curvature of space and the microwave background, match current observations, supporting their hypothesis.

To further test their predictions, the researchers hope to make use of next-generation gravitational wave observatories.The scientists calculated the properties of the gravitational waves produced during black hole formation in their model and found that they could be detected by upcoming gravitational observatories like the Laser Interferometer Space Antenna (LISA) and the Einstein Telescope. These detections could confirm whether primordial black holes are indeed dark matter; however, it could take more than a decade before either facility sees first light.

"This work is important in the sense that it provides a natural way of forming small yet still present black holes forming dark matter in a framework which is not the usual one based on inflation," Peter said. "Other works currently investigate the behavior of such tiny black holes around stars, potentially leading to a way of detecting them in the future."

Nothing in our universe stands still: Earth orbits the sun, the sun circles the galaxy, and even galaxies are constantly on the move. So why is everything in space in motion?

It all comes down to how the universe and the objects within it were made, Edward Gomez, an astrophysicist and the education director at Las Cumbres Observatory, told Live Science. Scientists think the universe began with the Big Bang, a superfast expansion from an infinitely dense single point that eventually led to the formation of everything we see today.

"From the very beginning of the universe, it started expanding outwards because the force of the Big Bang caused everything to move apart," Gomez said.

"It's sort of the imprint of the beginning," said Carol Christian, an astrophysicist and outreach project scientist for the Hubble Space Telescope at the Space Telescope Science Institute in Baltimore. "The beginning was movement, and so movement has been built into the universe from the very beginning."

Related: Does the universe rotate?

So one reason everything in space is in motion is because the universe is expanding. But that expansion has effects only on very large scales. "We only see it really happening on things that are very far apart or far away, because it's not necessarily that these objects are moving through space," Gomez said. "It's that the space in between objects is getting bigger."

On smaller scales, though, rotation is the movement that rules objects in space. "This spinning thing is kind of endemic in the universe, too," Christian told Live Science. "There isn't anything that doesn't rotate."

That's due to angular momentum: When two objects in space move close together, their mutual gravity pulls them toward each other, and if they don't collide or fly in different directions, they tend to orbit each other. This phenomenon affects everything, from the smallest mineral grains to the largest galaxies.

"The solar system was made like a pizza is made … If you're making an Italian pizza, you throw the pizza dough up, and as you spin it, it flattens out into a disc," Gomez said. "And that's fundamentally how our solar system is made: This thing called angular momentum, that spinning effect stretches things out into a disc."

That's why the planets in the solar system orbit the sun: The solar system began as a spinning mass of gas and dust that eventually coalesced into a star and planets. Along the way, angular momentum ensured it never stopped spinning.

But a galaxy's spinning effect happens differently than you'd expect from just the stuff we can see.

"It spins as if it were like a pizza base, as if it was solid instead of being made up of individual components, stars," Gomez said. "It should be that the [stars] further out should be going slower than the ones in the center. But actually, you don't see that … and that's one of the first indicators that the universe had something crazy that you can't see that we now call dark matter."

Dark matter doesn't interact with light, so we can't see it with telescopes. However, it does have mass and interacts with other objects that have mass through gravitational effects. Dark matter also experiences angular momentum. It's another reason everything in space is moving.

In the end, motion is a fundamental ingredient in the universe. It "shows that the universe is alive — not in a sense of being conscious, but you know, things are happening — chemical reactions, physical reactions are happening, and that requires energy," Gomez said. "And the most basic form of energy is motion."