Physicists around the world remain deeply divided on key mysteries of the universe, from dark matter to quantum gravity. The standard cosmological model failed to gain majority support, and no leading theory dominated the survey results. The largest survey ever conducted among physicists worldwide reveals surprisingly little agreement on some of the field’s biggest mysteries, [...]
James Webb Space Telescope (JWST) data have revealed hidden stars that astronomers say are unexpectedly increasing the mass of early galaxies.
JWST‘s ability to see deep into the cosmos gives astronomers insight into the early universe and challenges prior expectations of what they would find there. Now, an international team led by astronomers from the Netherlands’ Leiden University recently reported the discovery of new stars in a paper published in Nature Astronomy.
With the discovery of these many previously unknown small stars, the researchers say astronomers may need to reconsider the expected mass of these early galaxies, as JWST reveals unexpected levels of development shortly after the Big Bang.
For their new work, the astronomers focused on nine massive galaxies in the early universe that had completed their main star-formation period. They combined JWST data with earlier observations from the Very Large Telescope in Chile, operated by the European Southern Observatory.
Spectroscopy is a crucial element of JWST data, breaking light down into separate spectra that allow astronomers to study stars and even planetary atmospheres across extreme distances. However, the smaller, fainter stars revealed in this new research can be much harder to detect than the brighter, more powerful ones.
“If a galaxy were a city, the brightest stars would be the skyscrapers you can immediately see from far away,” said first author Chloe Cheng. “Our models show that behind the brightest stars there is a much larger population of small stars, like houses among the skyscrapers. This means that the galaxy as a whole is much more massive than previous estimates suggested.”
Working with data limited by the sensitivity of tools, researchers previously were unable to see as many smaller stellar objects. Researchers then assumed a similar ratio of small to large stars across the universe, which these new findings are now challenging.
Instead, they found ancient massive galaxies filled with many more small stars than previously expected, and far more than in our own Milky Way galaxy today, which is a smaller galaxy. The mass differences produced by this glut of tiny stars increased the expected mass of the galaxy under 1.5 billion years old by fourfold.
“Measurements like these were simply not possible until recently,” explained co-author Martje Slob. “We needed not only a telescope capable of collecting enough light, but also exceptionally high-quality spectra and new analysis techniques. Only then could we reliably distinguish the subtle features of small stars from the light of much brighter stars.”
Launched almost five years ago, JWST has continually defied what astronomers expected to find in the ancient universe. It turns out that the universe shortly after the Big Bang was more massive and had undergone more development than previously considered possible. The new findings add to those ongoing discoveries.
“This result shows that much more mass than we thought is hidden in small stars,” said study lead Professor Mariska Kriek. “It has implications for many areas of astronomy. Small stars often have planets orbiting them, so if there were many more small stars in the early Universe than we thought, there may also have been more planets.”
To follow up on this exciting discovery, the team plans to look even further back into the universe’s past in future observations that will study some of the universe’s very earliest stars.
The paper, “Hidden Mass in Early Galaxies Revealed by Bottom-Heavy Initial Mass Functions,” appeared in Nature Astronomy on August 18, 2026.
Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org.
Welcome to this edition of The Intelligence Brief… This week, NASA engineers successfully extended the operational life of the iconic Voyager 2 spacecraft through a carefully orchestrated power-saving procedure, raising new hopes that the legendary probe may continue exploring interstellar space well into the 2030s. In our analysis, we’ll examine 1) how engineers carried out the ambitious “Big Bang” operation to conserve the spacecraft’s dwindling power supply, 2) why Voyager’s aging radioisotope power system presents an ever-growing challenge, 3) how NASA hopes to keep both Voyager probes returning valuable scientific data decades after their original missions ended, and 4) what the remarkable longevity of the twin spacecraft reveals about one of the most successful engineering achievements in the history of space exploration.
“Voyager revolutionized our conception of the solar system. After almost 400 years, it transformed the astronomical objects observed by Galileo into true ‘worlds’.”
If you enjoy the news and perspectives offered by The Debrief, make sure that you aren’t missing our stories by making us one of your “preferred sources” on Google News. You can simply follow this link to add The Debrief to your list of favorites, and you can read more about Google’s preferred sources in our article here.
This week, engineering teams at NASA’s Jet Propulsion Laboratory succeeded in once again extending the lifespan of one of the space agency’s most iconic spacecraft.
Power systems have reportedly now been freed up on Voyager 2, allowing the famous space probe, which is now making its way through interstellar space, to continue sending valuable scientific data back to Earth with help from NASA’s Deep Space Network.
The largest and most sensitive telecommunications network in the entire solar system, for several decades now, the Deep Space Network has enabled Voyager 2 and its twin, Voyager 1, to relay science data about our planetary neighborhood back to Earth.
Launched on August 20, 1977, from Cape Canaveral, Florida, Voyager 2 is truly ancient by the standards of modern space exploration. The probe blasted off on its cosmic mission 16 days before its twin, Voyager 1, to account for specific orbital path needs.
While both spacecraft completed their official planetary flyby missions decades ago, each has overcome seemingly impossible odds in recent years and has managed to continue dispatching science data from the furthest points in the cosmos any human-built spacecraft has ever reached.
But how much longer will Voyager’s ongoing extended mission really be able to last?
Recently, to free up power on Voyager 2, JPL engineers engaged in an effort dubbed the “Big Bang,” which involved simultaneous shutdowns of some of the devices on board the spacecraft and reallocating lower-power alternatives.
One of the key hurdles with this operation involves making sure Voyager 2 remains warm enough to function properly, since current power systems combined with its tremendous distance from the Sun keep the aging spacecraft’s core and instrument bays at a frosty 38.5°F—temperatures that are already dangerously close to the freezing point.
The primary source of power aboard both Voyagers is their radioisotope thermoelectric generators, which generate heat using decaying plutonium, which is thereby converted into electricity. Every year, an average of four watts of power is lost as the plutonium supplies of each spacecraft continue to deplete.
Still, while their power stores are perilously close to zero, both remain online nearly a half-century after their launches in the late 1970s.
Over the last several years, several science instruments on each of the spacecraft have been disabled to help preserve power. According to NASA, the recent “Big Bang” operation helped prevent the shutdown of another instrument on Voyager 2 before the end of the year.
“The savings should provide power to keep its three instruments operating for at least an extra year,” read a NASA statement issued this week. JPL engineers also plan to perform the same operation on Voyager 1, which is currently even farther away than Voyager 2.
The Voyager team hopes these measures will extend the spacecraft’s operational lifetimes into the 2030s, allowing them to continue returning valuable scientific data for years to come, provided they remain in contact with NASA’s Deep Space Network.
The spacecraft have already “far surpassed their original mission of exploring the outer planets,” said Patrick Koehn, Voyager program scientist at NASA Headquarters in Washington, in a statement last year.
“Every bit of additional data we have gathered since then is not only valuable bonus science for heliophysics but also a testament to the exemplary engineering that has gone into the Voyagers — starting nearly 50 years ago and continuing to this day,” Koehn added.
Launched more than 46 years ago, the twin Voyager I and II probes represent the longest-running missions in NASA history, as well as the farthest spacecraft ever to have travelled from Earth.
During their missions, both Voyager spacecraft visited Jupiter and Saturn, and Voyager II also flew by Uranus and Neptune. Now, with the successful implementation of the “Big Bang” procedure on Voyager 2, which is soon to be undertaken with its farther distant twin spacecraft in the months ahead, the two iconic spacecraft will at very least be secured for continuous operations through the end of the year, and with a bit of luck, on into the 2030s.
That concludes this week’s installment of The Intelligence Brief. You can read past editions of our newsletter at our website, or if you found this installment online, don’t forget to subscribe and get future email editions from us here. Also, if you have a tip or other information you’d like to send along directly to me, you can email me at micah [@] thedebrief [dot] org, or reach me on X: @MicahHanks.
Here are the top stories we’re covering right now…
A new cosmic bounce model suggests that remnants from a pre-Big Bang Universe may still exist today. What if some of the Universe’s oldest objects are actually older than the Big Bang itself? A new study from the University of Portsmouth suggests that ancient black holes may have survived from a time before the Universe [...]
Scientists from Goethe University, Frankfurt, studying alternatives to black holes have suggested a mathematically viable formation mechanism for one proposed alternative called a ‘Gravastar.’
Although the team behind the newly proposed gravastar formation mechanism conceded that black holes still represent the simplest and most natural solution to gravitational collapse, they also suggest that the physics behind the alternative, which doesn’t require a single point where spacetime curves infinitely, called a “singularity,” can make them “easier to accept” than black holes.
If correct, and some or all black holes are, in fact, gravastars that mimic their expected properties, the work would establish a valid formation mechanism that could rewrite decades of accepted science and open a new field of research dedicated to understanding this previously misunderstood phenomenon.
According to standard cosmology theories, black holes form when extremely massive stars stop generating energy, allowing the force of gravity to take over and collapse the remaining matter into a single point, or singularity. Unfortunately, the research team behind the new study notes that “the laws of physics break down” within the singularity, making the formation of the resulting black hole a difficult phenomenon to predict.
“How can spacetime be curved infinitely at that point, the singularity?” asks the team’s statement announcing the new approach. They also note that no information escapes a black hole, including light, making studying its inner workings effectively impossible, and opening up the possibility that “black holes are in fact entirely different objects.”
Some options have been proposed, including ‘horizonless’ black hole mimickers. The team notes that these proposed options are “mathematically consistent alternatives” that also address the physics challenges posed by traditional black holes.
Still, how these alternative objects form has remained largely unclear. The research team said this lack of a formation mechanism constitutes “a significant open problem” since understanding how they form is the “first step” to determining if they truly exist.
In the new formation model, theoretical physicists Daniel Jampolski and Theoretical Astrophysics Professor Luciano Rezzolla from Goethe University showed that the collapse of a dying star may not go far enough that it reaches the point of no return, where “the collapse to a black hole is inevitable.”
Instead, the collapse slows down near a point scientists call the Schwarzschild radius, then stops. The result is what the team termed a “miniature universe” within the collapsing matter, which they compared to the dynamics of the Big Bang, which most theorists agree formed the entire universe.
Since the universe’s expansion was driven by dark energy, the new model proposes that the dark energy within the mini-universe establishes an “equilibrium” with the counteracting force of gravity, therefore halting the collapse of the star “before a black hole can form.”
“The Big Bang of the emerging universe can unfold once the star has already collapsed almost to the point of becoming a black hole,” explained Jampolski, who discovered the black hole alternative gravastar solution in his master’s thesis while under the supervision of Professor Rezzolla.
When discussing the impact of their proposed black hole alternative formation model, Jampolski said that from a mathematical and physics standpoint, it is “easier to imagine that the Big Bang occurs only at a very late stage, when matter has already been compressed to an extreme degree, thereby giving rise to new effects.” The team also notes that the unresolved behavior of matter in this environment “leaves room for new physics.”
Although the team’s model offers a mathematically sound formation for an alternative to black holes, Rezzolla notes that the search for gravastars or other alternatives “should not suggest a skepticism towards black holes,” which, he adds, “still represent the most natural and simplest solution to the fate of gravitational collapse.”
Instead, the Goethe professor explained, his general role as a scientist and his specific discipline as a theoretical physicist make it essential that he and his colleagues “maintain an unbiased approach towards what we do not know and hence explore both the accepted wisdom and the more exotic interpretations.”
“History teaches us that it is not unusual for the latter to become the former,” the professor added.
The paper “Formation of gravastars” was published in the journal Physical Review D.
Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.
New mathematical research suggests dark energy may not be needed to explain the accelerating expansion of the universe, challenging the foundations of the standard cosmological model. Mathematicians are questioning whether dark energy is actually responsible for the universe’s accelerating expansion. In a new study published in Proceedings of the Royal Society A, researchers at the [...]Scientists believe an unusual LIGO detection may be evidence of a primordial black hole, potentially linking these long-theorized objects to the mystery of dark matter. Scientists at the University of Miami believe they may be closing in on evidence for one of the most elusive objects in the universe: primordial black holes. While definitive proof [...]
Login