Category: 7. Science

A spectacular celestial event is set to light up the skies on the night of September 7–8, 2025, as the Moon undergoes a total lunar eclipse, turning an eerie, deep red for 82 minutes. Known as a Blood Moon, this will be the last total lunar eclipse of the year and is expected to be visible to nearly 77% of the global population. Unlike many eclipses confined to specific regions, this phenomenon will be observable across much of Asia, Australia, Europe, and Africa, with India offering some of the clearest views. For skywatchers and astronomy enthusiasts, the event promises both breathtaking beauty and scientific intrigue.

Why the moon turns blood red

A Blood Moon occurs during a total lunar eclipse when Earth comes directly between the Sun and the Moon. Instead of the Moon disappearing into complete darkness, sunlight passes through Earth’s atmosphere, which bends, filters, and scatters the light. Shorter blue and violet wavelengths scatter away, while longer red and orange wavelengths reach the Moon, giving it its iconic crimson glow. This phenomenon, known as Rayleigh scattering, is the same reason sunsets appear red. NASA notes that the depth of red can vary depending on atmospheric conditions, such as dust, clouds, or volcanic ash.

Date, timings, and totality phase in India

The September 2025 Blood Moon will unfold over more than five hours, with the totality lasting 82 minutes:

During totality, the Moon will appear its deepest red, providing the best window for observation and photography.

Indian cities to view the blood moon

The eclipse will be visible across much of India. Some of the best cities to observe it include:

For the clearest view, observers should find open areas such as rooftops, terraces, or fields away from city lights. Cloud cover, heavy pollution, or smog may reduce visibility in certain regions.

Tips for observing the blood moon

Unlike solar eclipses, lunar eclipses can be safely observed with the naked eye. To enhance your experience:

Significance of the September 2025 blood moon

This Blood Moon is significant due to its long duration and wide visibility. Millions in India and across Asia will experience it simultaneously, making it a shared astronomical event. Historically, Blood Moons carried cultural and spiritual meanings, often interpreted as omens or signs of transformation. Today, they inspire awe and curiosity about the universe. Scientists can also study the Moon’s red intensity to learn about Earth’s atmosphere, as particles and dust in the air influence the Moon’s crimson shade. Skywatchers are encouraged to share their observations on social media, connecting with global communities of astronomy enthusiasts. Capturing and documenting the event can also help beginners appreciate the beauty and science of lunar phenomena.

A remarkable fossil has revealed the largest predator of the species Pampaphoneus biccai. This astonishing discovery dates back to a staggering 265 million years and was unearthed in the rural region of São Gabriel, located in Southern Brazil.

Details about the unearthed fossil

The fossil has revealed the world’s largest predator and is a true wonder, boasting a complete skull along with some key skeletal remains, including ribs and arm bones.

Pampaphoneus, a member of the early therapsid group known as dinocephalians, inhabited our planet just before the most catastrophic extinction event in Earth’s history, which wiped out a staggering 86 percent of all animal species across the globe.

Prior to this cataclysmic event, dinocephalians were among the dominant groups of large land-dwelling animals. These creatures came in various sizes and had both meat-eating and plant-eating members.

Dinocephalians were distinguished by their thick skull bones, which is how they got their name, meaning “terrible head” in Greek.

Significance of this discovery

Although well-documented in regions such as South Africa and Russia, these animals are quite rare in other parts of the world. Remarkably, Pampaphoneus biccai stands as the sole known species of its kind in Brazil.

“The fossil was found in middle Permian rocks, in an area where bones are not so common, but always hold pleasant surprises,” explained Mateus A. Costa Santos, the primary researcher behind the study and a graduate student at the Paleontology Laboratory, Federal University of Pampa (UNIPAMPA).

He further said, “Finding a new Pampaphoneus skull after so long was extremely important for increasing our knowledge about the animal, which was previously difficult to differentiate from its Russian relatives.”

The diligent efforts of paleontologists from UNIPAMPA and the Federal University of Rio Grande do Sul (UFRGS) paid off. They invested a full month of strenuous, day-to-day fieldwork to retrieve this valuable fossil.

Professor Stephanie E. Pierce, a co-author of the study and a member of the Department of Organismic and Evolutionary Biology, as well as the Curator of Vertebrate Paleontology and Mammalogy at the Museum of Comparative Zoology at Harvard, played a vital role in examining this creature.

She collaborated with the senior author and head of the lab, Professor Felipe Pinheiro of UNIPAMPA, as part of their ongoing research on Brazil’s Permo-Triassic fossil record.

Professor Pierce remarked, “This animal was a gnarly-looking beast, and it must have evoked sheer dread in anything that crossed its path.”

She further said, “Its discovery is key to providing a glimpse into the community structure of terrestrial ecosystems just prior to the biggest mass extinction of all time. [It is a] spectacular find that demonstrates the global importance of Brazil’s fossil record.”

The second Pampaphoneus skull ever found in South America

This specimen marks the second Pampaphoneus skull ever unearthed in South America. Notably, it surpasses the size of the first discovery and offers an unparalleled insight into its physical characteristics due to the remarkable preservation of its bones.

265-million-year-old fossil belongs to oldest, largest South American predator before dinosaurs
Pampaphoneus biccai is the oldest and largest predator whose fossils were discovered in South America. pic.twitter.com/jWHyQZQGQM

— R (@Vinodrviv) September 13, 2023

Professor Felipe Pinheiro elaborated, “Pampaphoneus played the same ecological role as modern big cats.”

He further said, “It was the largest terrestrial predator we know of from the Permian in South America. The animal had large, sharp canine teeth adapted for capturing prey. Its dentition and cranial architecture suggest that its bite was strong enough to chew bones, much like modern-day hyenas.”

A potentially unidentified fossil of Pampaphoneus skull

Despite the already substantial size of the newly discovered Pampaphoneus skull, measuring nearly forty centimeters, research indicates the existence of a previously unidentified fossil that could represent a third individual.

Remarkably, this potential third specimen could be up to twice the size of the recent find. While we only have a fragment of its jaw, the distinctive characteristics present are enough to classify it as belonging to the Pampaphoneus species.

Scientists estimate that the largest Pampaphoneus individuals might have stretched to nearly three meters in length and weighed around four hundred kilograms. These skilled predators had a varied diet, including small to medium-sized animals.

Paleontological potential of Pampa

Interestingly, in the same area where this fossil was discovered, some of the creatures that may have served as their prey have also been identified. These include the small dicynodont Rastodon and the massive amphibian Konzhukovia.

The Pampaphoneus specimen, along with the other creatures uncovered in this region, underscores the rich paleontological potential of the Pampa region for making significant fossil breakthroughs.

NASA scientists have uncovered massive fragments of ancient planetary collisions buried deep within Mars’ mantle, shedding light on the planet’s tumultuous early history. Preserved for over four billion years, these relics provide a rare window into the processes that shaped rocky planets in the inner Solar System. By analysing seismic data from the now-retired InSight lander, researchers were able to construct detailed maps of Mars’ interior, revealing scars from an era of intense bombardment. These findings not only illuminate the violent forces that influenced Mars’ formation but also help scientists understand how similar impacts may have shaped Earth and other terrestrial planets, offering a broader perspective on planetary evolution across our solar system.

NASA discovers billions-year-old collision fragments deep in Mars’ mantle

Mars’ mantle, the thick layer of solid rock beneath the crust, contains huge lumps of rocky debris, some stretching up to 2.5 miles in diameter. These fragments are the remnants of early planetary collisions, likely caused by large protoplanetary bodies striking Mars during the chaotic formative period of the Solar System.Unlike Earth, which is geologically active due to plate tectonics, Mars lacks such recycling mechanisms. On Earth, tectonic movements and volcanic activity continuously reshape the mantle and crust, erasing evidence of most early impacts. Mars, in contrast, has remained relatively geologically stable, preserving these ancient scars almost like a time capsule from the planet’s earliest days.

InSight mission reveals Mars’ hidden interior through seismic analysis

The discovery was made possible by the InSight mission, which operated from 2018 to 2022. InSight recorded over 1,300 marsquakes, ranging from minor tremors to stronger seismic events. These quakes generated waves that traveled through Mars’ interior, and scientists analyzed the timing and speed of these waves to detect variations in material density and composition.Where seismic waves slowed down, researchers identified localized regions of buried debris—the preserved remnants of ancient impacts. These waves penetrated deep into the mantle, which extends nearly 960 miles beneath the surface, providing a three-dimensional view of Mars’ interior structure.

Mars vs Earth: The role of plate tectonics in preserving history

One key reason Mars has retained evidence of its violent past is the absence of plate tectonics. On Earth, tectonic plates shift constantly, recycling crustal and mantle material. This process, while vital for Earth’s geological life cycle, erases much of the evidence of early collisions.Mars’ stagnant mantle, by contrast, has evolved very slowly over billions of years, allowing the preservation of ancient planetary fragments. The survival of these fragments provides scientists with a rare window into the Solar System’s formative processes, helping reconstruct the violent conditions under which terrestrial planets formed.

Scientific Insights: Understanding Mars’ early history

The discovery has major implications for planetary science:

Scientists highlight Mars as a planetary time capsule revealing ancient mantle fragments

Constantinos Charalambous, lead author from Imperial College London, emphasised the uniqueness of the findings:“We’ve never seen the inside of a planet in such fine detail and clarity before. What we’re seeing is a mantle studded with ancient fragments. Their survival to this day tells us Mars’ mantle has evolved sluggishly over billions of years. On Earth, features like these may well have been largely erased.”Tom Pike, co-author of the study, added: “We knew Mars was a time capsule bearing records of its early formation, but we didn’t anticipate just how clearly we’d be able to see with InSight.”Also Read | World witnessed the longest 74-minute solar eclipse in history with Concorde 001 flying at 2,500 km/h

Get the key facts behind this story in our 1-minute read

Exciting evidence unveiled: The James Webb Space Telescope may have spotted a Saturn-like gas giant orbiting Alpha Centauri A, the closest Sun-like star to Earth

Closest potential exoplanet yet: This candidate – if confirmed – would be the nearest world discovered orbiting a star like our Sun in its habitable zone

Imaging with MIRI: Webb’s Mid-Infrared Instrument (MIRI), using a coronagraph to block out starlight, revealed the faint planetary signal near Alpha Centauri A

Planetary details: The object appears to have a similar mass to Saturn and orbits roughly two astronomical units from its star – twice Earth–Sun distance

Not habitable itself: As a gas giant, it couldn’t support life, but its location in the habitable zone makes the system intriguing

Disappearing act: The candidate, dubbed S1, was detected in 2024 but not seen again in follow-up Webb observations in early 2025, likely due to its orbit obscuring it temporarily

Orbital dynamics: Modeling suggests S1 could be on an eccentric orbit inclined relative to the Alpha Centauri A–B plane, with a 2–3-year period

Eyes on the sky: If this candidate is real, it may reappear around 2026–2027, giving astronomers a chance to confirm its existence, and possibly search for moons

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SLAC scientists created gold hydride in extreme lab conditions. The work sheds light on dense hydrogen and fusion processes.

By chance and for the first time, an international team of researchers led by scientists at the U.S. Department of Energy’s SLAC National Accelerator Laboratory succeeded in creating solid binary gold hydride—a compound composed solely of gold and hydrogen atoms.

The team had originally set out to investigate how hydrocarbons, molecules made of carbon and hydrogen, transform into diamonds under extreme pressure and heat. During experiments at the European XFEL (X-ray Free-Electron Laser) in Germany, they placed hydrocarbon samples with a thin layer of gold foil, intended only to absorb X-rays and transfer heat to the relatively weakly absorbing hydrocarbons. Unexpectedly, alongside diamond formation, they observed the creation of gold hydride.

“It was unexpected because gold is typically chemically very boring and unreactive – that’s why we use it as an X-ray absorber in these experiments,” explained Mungo Frost, a staff scientist at SLAC and the study’s lead author. “These results suggest there’s potentially a lot of new chemistry to be discovered at extreme conditions where the effects of temperature and pressure start competing with conventional chemistry, and you can form these exotic compounds.”

The findings, published in Angewandte Chemie International Edition, demonstrate how chemical behavior can shift dramatically under extreme environments, such as those found deep inside planets or within hydrogen-fusing stars.

Studying dense hydrogen

To achieve these results, the researchers compressed hydrocarbon samples to pressures exceeding those inside Earth’s mantle using a diamond anvil cell. They then exposed the samples to bursts of X-ray pulses from the European XFEL, heating them above 3,500 degrees Fahrenheit. By analyzing how the X-rays scattered from the samples, the team tracked the structural changes taking place.

As anticipated, the data confirmed that carbon atoms had arranged into a diamond lattice. However, they also revealed unexpected signals: hydrogen atoms had reacted with the gold foil to form gold hydride.

At the conditions generated in the experiment, hydrogen existed in a dense, “superionic” state, in which hydrogen atoms moved freely within the rigid gold lattice. This behavior enhanced the conductivity of the gold hydride, offering new insight into the behavior of materials under extreme pressures and temperatures.

Hydrogen, which is the lightest element of the periodic table, is tricky to study with X-rays because it scatters X-rays only weakly. Here, however, the superionic hydrogen interacted with the much heavier gold atoms, and the team was able to observe hydrogen’s impact on how the gold lattice scattered X-rays. “We can use the gold lattice as a witness for what the hydrogen is doing,” Mungo said.

The gold hydride offers a way to study dense atomic hydrogen under conditions that might also apply to other situations that are experimentally not directly accessible. For example, dense hydrogen makes up the interiors of certain planets, so studying it in the lab could teach us more about those foreign worlds. It could also provide new insights into nuclear fusion processes inside stars like our sun and help develop technology to harness fusion energy here on Earth.

Exploring new chemistry

In addition to paving the way for studies of dense hydrogen, the research also offers an avenue for exploring new chemistry. Gold, which is commonly regarded as an unreactive metal, was found to form a stable hydride at extremely high pressure and temperature. In fact, it appears to be only stable at those extreme conditions as when it cools down, the gold and hydrogen separate. The simulations also showed that more hydrogen could fit in the gold lattice at higher pressure.

The simulation framework could also be extended beyond gold hydride. “It’s important that we can experimentally produce and model these states under these extreme conditions,” said Siegfried Glenzer, High Energy Density Division director and professor for photon science at SLAC and the study’s principal investigator. “These simulation tools could be applied to model other exotic material properties in extreme conditions.”

Reference: “Synthesis of Gold Hydride at High Pressure and High Temperature” by Mungo Frost, Kilian Abraham, Alexander F. Goncharov, R. Stewart McWilliams, Rachel J. Husband, Michal Andrzejewski, Karen Appel, Carsten Baehtz, Armin Bergermann, Danielle Brown, Elena Bykova, Anna Celeste, Eric Edmund, Nicholas J. Hartley, Konstantin Glazyrin, Heinz Graafsma, Nicolas Jaisle, Zuzana Konôpková, Torsten Laurus, Yu Lin, Bernhard Massani, Maximilian Schörner, Maximilian Schulze, Cornelius Strohm, Minxue Tang, Zena Younes, Gerd Steinle-Neumann, Ronald Redmer and Siegfried H. Glenzer, 4 August 2025, Angewandte Chemie International Edition.
DOI: 10.1002/anie.202505811

Parts of this work were supported by the DOE Office of Science.

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In the deepest parts of the Pacific Ocean, a glowing yellow worm has mastered survival in one of the most toxic places on Earth.

Bathed in arsenic and sulfide from hydrothermal vents, it neutralizes the poisons by transforming them into golden mineral crystals, turning deadly chemicals into glittering protection.

Poison-Resistant Worm Discovery

A deep-sea worm that lives around hydrothermal vents has evolved a remarkable survival trick: it combines two deadly substances, arsenic and sulfide, inside its cells to create a far less harmful mineral. The discovery, described by Chaolun Li of the Institute of Oceanology, CAS, China, and his colleagues, was published August 26th in the open-access journal PLOS Biology.

The species, known as Paralvinella hessleri, is the only animal that can withstand the hottest zones of deep-sea vents in the western Pacific. These vents gush out superheated, mineral-rich water containing high concentrations of sulfide and arsenic. Over time, the arsenic accumulates in the worm’s tissues, in some cases accounting for more than 1% of its total body weight.

Life in Extreme Deep-Sea Vents

To uncover how P. hessleri survives such a hostile environment, Li’s team used advanced microscopy along with DNA, protein, and chemical analysis. Their work revealed an entirely new detoxification process. The worm traps arsenic particles in its skin cells, where they interact with sulfide from the vent fluids to form clusters of a bright yellow mineral called orpiment.

This unusual process sheds light on a strategy that researchers describe as “fighting poison with poison.” It allows the worm to live in an environment that should be lethally toxic. Other studies suggest that some closely related worm species and certain snails in the western Pacific also build up large amounts of arsenic and may rely on a similar adaptation.

Fighting Poison With Poison

Coauthor Dr. Hao Wang adds, “This was my first deep-sea expedition, and I was stunned by what I saw on the ROV monitor—the bright yellow Paralvinella hessleri worms were unlike anything I had ever seen, standing out vividly against the white biofilm and dark hydrothermal vent landscape. It was hard to believe that any animal could survive, let alone thrive, in such an extreme and toxic environment.”

Dr. Wang says, “What makes this finding even more fascinating is that orpiment—the same toxic, golden mineral produced by this worm—was once prized by medieval and Renaissance painters. It’s a curious convergence of biology and art history, unfolding in the depths of the ocean.”

A Strange Link to Art History

The authors note, “We were puzzled for a long time by the nature of the yellow intracellular granules, which had a vibrant color and nearly perfect spherical shape. It took us a combination of microscopy, spectroscopy, and Raman analysis to identify them as orpiment minerals—a surprising finding.”

The authors conclude, “We hope that this ‘fighting poison with poison’ model will encourage scientists to rethink how marine invertebrates interact with and possibly harness toxic elements in their environment.”

Reference: “A deep-sea hydrothermal vent worm detoxifies arsenic and sulfur by intracellular biomineralization of orpiment (As2S3)” by Hao Wang, Lei Cao, Huan Zhang, Zhaoshan Zhong, Li Zhou, Chao Lian, Xiaocheng Wang, Hao Chen, Minxiao Wang, Xin Zhang and Chaolun Li, 26 August 2025, PLOS Biology.
DOI: 10.1371/journal.pbio.3003291

Funding: This work was supported by grants from Natural Science Foundation of China (No. 42476133 to H.W.), Science and Technology Innovation Project of Laoshan Laboratory (Project Number No. LSKJ202203104 to H.W.), National Key RandD Program of China (Project Number 2018YFC0310702 to H.W.), Natural Science Foundation of China (Grant No. 42030407 to C.Li), and the NSFC Innovative Group Grant (No. 42221005 to M.X.W.). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

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The inside of Mars isn’t smooth and uniform like familiar textbook illustrations. Instead, new research reveals it’s chunky — more like a Rocky Road brownie than a neat slice of Millionaire’s Shortbread.

We often picture rocky planets like Earth and Mars as having smooth, layered interiors — with crust, mantle, and core stacked like the biscuit base, caramel middle, and chocolate topping of a millionaire’s shortbread. But the reality for Mars is rather less tidy.

Seismic vibrations detected by NASA’s InSight mission revealed subtle anomalies, which led scientists from Imperial College London and other institutions to uncover a messier reality: Mars’s mantle contains ancient fragments up to 4km wide from its formation — preserved like geological fossils from the planet’s violent early history.

History of gigantic impacts

Mars and the other rocky planets formed about 4.5 billion years ago, as dust and rock orbiting the young Sun gradually clumped together under gravity.

Once Mars had largely taken shape, it was struck by giant, planet-sized objects in a series of near-cataclysmic collisions — the kind that also likely formed Earth’s Moon.

“These colossal impacts unleashed enough energy to melt large parts of the young planet into vast magma oceans,” said lead researcher Dr Constantinos Charalambous from the Department of Electrical and Electronic Engineering at Imperial College London. “As those magma oceans cooled and crystallised, they left behind compositionally distinct chunks of material — and we believe it’s these we’re now detecting deep inside Mars.”

These early impacts and their aftermath scattered and mixed fragments of the planet’s early crust and mantle — and possibly debris from the impacting objects themselves — into the molten interior. As Mars slowly cooled, these chemically diverse chunks were trapped in a sluggishly churning mantle, like ingredients folded into a Rocky Road brownie mix, and the mixing was too weak to fully smooth things out.

Unlike Earth, where plate tectonics continuously recycle the crust and mantle, Mars sealed up early beneath a stagnant outer crust, preserving its interior as a geological time capsule.

“Most of this chaos likely unfolded in Mars’s first 100 million years,” says Dr Charalambous. “The fact that we can still detect its traces after four and a half billion years shows just how sluggishly Mars’s interior has been churning ever since.”

Listening into Mars

The evidence comes from seismic data recorded by NASA’s InSight lander — in particular, eight especially clear marsquakes, including two triggered by two recent meteorite impacts that left 150-metre-wide craters in Mars’s surface.

InSight picks up seismic waves travelling through the mantle and the scientists could see that waves of higher frequencies took longer to reach its sensors from the impact site. These signs of interference, they say, shows that the interior is chunky rather than smooth.

“These signals showed clear signs of interference as they travelled through Mars’s deep interior,” said Dr Charalambous. “That’s consistent with a mantle full of structures of different compositional origins — leftovers from Mars’s early days.”

“What happened on Mars is that, after those early events, the surface solidified into a stagnant lid,” he explained. “It sealed off the mantle beneath, locking in those ancient chaotic features — like a planetary time capsule.”

Unlike the interior of Earth

Earth’s crust, by comparison, is always slowly shifting and recycling material from the surface into our planet’s mantle – at tectonic plates such as the Cascadia subduction zone where some of the plates forming the Pacific Ocean floor are pushed under the North American continental plate.

The chunks detected in Mars’s mantle follow a striking pattern, with a few large fragments — up to 4 km wide — surrounded by many smaller ones.

Professor Tom Pike, who worked with Dr Charalambous to unravel what caused these chunks, said: “What we are seeing is a ‘fractal’ distribution, which happens when the energy from a cataclysmic collision overwhelms the strength of an object. You see the same effect when a glass falls onto a tiled floor as when a meteorite collides with a planet: it breaks into a few big shards and a large number of smaller pieces. It’s remarkable that we can still detect this distribution today.”

The finding could have implications for our understanding of how the other rocky planets — like Venus and Mercury — evolved over billions of years. This new discovery of Mars’s preserved interior offers a rare glimpse into what might lie hidden beneath the surface of stagnant worlds.

“InSight’s data continues to reshape how we think about the formation of rocky planets, and Mars in particular,” said Dr Mark Panning of NASA’s Jet Propulsion Laboratory in Southern California. JPL led the InSight mission before its end in 2022. “It’s exciting to see scientists making new discoveries with the quakes we detected!”

“These mysterious objects are candidate galaxies in the early universe, meaning they could be very early galaxies,” said Haojing Yan, an astronomy professor in Mizzou’s College of Arts and Science and co-author on the study. “If even a few of these objects turn out to be what we think they are, our discovery could challenge current ideas about how galaxies formed in the early universe — the period when the first stars and galaxies began to take shape.”

But identifying objects in space doesn’t happen in an instant. It takes a careful step-by-step process to confirm their nature, combining advanced technology, detailed analysis and a bit of cosmic detective work.

Step 1: Spotting the first clues

Mizzou’s researchers started by using two of JWST’s powerful infrared cameras: the Near-Infrared Camera and the Mid-Infrared Instrument. Both are specifically designed to detect light from the most distant places in space, which is key when studying the early universe.

Why infrared? Because the farther away an object is, the longer its light has been traveling to reach us.

“As the light from these early galaxies travels through space, it stretches into longer wavelengths — shifting from visible light into infrared,” Yan said. “This stretching is called redshift, and it helps us figure out how far away these galaxies are. The higher the redshift, the farther away the galaxy is from us on Earth, and the closer it is to the beginning of the universe.”

Step 2: The ‘dropout’

To identify each of the 300 early galaxy candidates, Mizzou’s researchers used an established method called the dropout technique.

“It detects high-redshift galaxies by looking for objects that appear in redder wavelengths but vanish in bluer ones — a sign that their light has traveled across vast distances and time,” said Bangzheng “Tom” Sun, a Ph.D. student working with Yan and the lead author of the study. “This phenomenon is indicative of the ‘Lyman Break,’ a spectral feature caused by the absorption of ultraviolet light by neutral hydrogen. As redshift increases, this signature shifts to redder wavelengths.”

Step 3: Estimating the details

While the dropout technique identifies each of the galaxy candidates, the next step is to check whether they could be at “very” high redshifts, Yan said.

“Ideally this would be done using spectroscopy, a technique that spreads light across different wavelengths to identify signatures that would allow an accurate redshift determination,” he said.

But when full spectroscopic data is unavailable, researchers can use a technique called spectral energy distribution fitting. This method gave Sun and Yan a baseline to estimate the redshifts of their galaxy candidates — along with other properties such as age and mass.

In the past, scientists often thought these extremely bright objects weren’t early galaxies, but something else that mimicked them. However, based on their findings, Sun and Yan believe these objects deserve a closer look — and shouldn’t be so quickly ruled out.

“Even if only a few of these objects are confirmed to be in the early universe, they will force us to modify the existing theories of galaxy formation,” Yan said.

Step 4: The final answer

The final test will use spectroscopy — the gold standard — to confirm the team’s findings.

Spectroscopy breaks light into different wavelengths, like how a prism splits light into a rainbow of colors. Scientists use this technique to reveal a galaxy’s unique fingerprint, which can tell them how old the galaxy is, how it formed and what it’s made of.

“One of our objects is already confirmed by spectroscopy to be an early galaxy,” Sun said. “But this object alone is not enough. We will need to make additional confirmations to say for certain whether current theories are being challenged.”

The study, “On the very bright dropouts selected using the James Webb Space Telescope NIRCam instrument,” was published in The Astrophysical Journal.

“Unlike most nearby planet-forming disks, where water vapor dominates the inner regions, this disk is surprisingly rich in carbon dioxide,” says Jenny Frediani, PhD student at the Department of Astronomy, Stockholm University.

“In fact, water is so scarce in this system that it’s barely detectable — a dramatic contrast to what we typically observe.”

A newly formed star is initially deeply embedded in the gas cloud from which it was formed and creates a disk around itself where planets in turn can be formed. In conventional models of planet formation, pebbles rich in water ice drift from the cold outer disk toward the warmer inner regions, where the rising temperatures cause the ices to sublimate. This process usually results in strong water vapor signatures in the disk’s inner zones. However, in this case, the JWST/MIRI spectrum shows a puzzlingly strong carbon dioxide signature instead.

“This challenges current models of disk chemistry and evolution since the high carbon dioxide levels relative to water cannot be easily explained by standard disk evolution processes,” Jenny Frediani explains.

Arjan Bik, researcher at the Department of Astronomy, Stockholm University, adds, “Such a high abundance of carbon dioxide in the planet-forming zone is unexpected. It points to the possibility that intense ultraviolet radiation — either from the host star or neighbouring massive stars — is reshaping the chemistry of the disk.”

The researchers also detected rare isotopic variants of carbon dioxide, enriched in either carbon-13 or the oxygen isotopes ¹⁷O and ¹⁸O, clearly visible in the JWST data. These isotopologues could offer vital clues to long-standing questions about the unusual isotopic fingerprints found in meteorites and comets — relics of our own Solar System’s formation.

This CO2-rich disk was found in the massive star-forming region NGC 6357, located approximately 1.7 kiloparsecs (about 53 quadrillion kilometers) away. The discovery was made by the eXtreme Ultraviolet Environments (XUE) collaboration, which focuses on how intense radiation fields impact disk chemistry.

Maria-Claudia Ramirez-Tannus from the Max Planck Institute for Astronomy in Heidelberg and lead of the XUE collaboration says that it is an exciting discovery: “It reveals how extreme radiation environments — common in massive star-forming regions — can alter the building blocks of planets. Since most stars and likely most planets form in such regions, understanding these effects is essential for grasping the diversity of planetary atmospheres and their habitability potential.”

Thanks to JWST’s MIRI instrument, astronomers can now observe distant, dust-enshrouded disks with unprecedented detail at infrared wavelengths — providing critical insights into the physical and chemical conditions that govern planet formation. By comparing these intense environments with quieter, more isolated regions, researchers are uncovering the environmental diversity that shapes emerging planetary systems. Astronomers at Stockholm University and Chalmers have helped develop the MIRI instrument which is a camera and a spectrograph that observes mid- to long-wavelength infrared radiation from 5 microns to 28 microns. It also has coronagraphs, specifically designed to observe exoplanets.

The study “XUE: The CO2-rich terrestrial planet-forming region of an externally irradiated Herbig disk” is published in Astronomy & Astrophysics.