Stars often end their lives with a dazzling explosion, creating and releasing material into the universe. This will then seed new life, leading to a cosmic cycle of birth, death and rebirth.
Astronomers around the world have been studying these explosions, called supernovae (derived from the Latin “an extremely bright new star”), and have discovered tens of different types.
In 2021, astronomers observed a bright supernova, dubbed SN2021yfj, two billion light years away. In a recent paper, published in Nature, astronomers observed it for more than a month and discovered that it exhibits the visible signatures of heavier elements – such as argon, silicon and sulphur – since the onset of the explosion. This was previously unobserved in any stellar explosion.
Supernovas violently eject stellar material into the cosmos, roughly keeping the same onion structure the star had before its death. This means that lighter materials – such as hydrogen and helium – will be in the outer layers and heavier ones – such as iron, silicon and sulphur – in the inner layers.
However, massive stars can lose part of their layers during their evolution via winds (like the Sun), great eruptions (like the star Eta Carinae), or a gravitational and energetic “tug of war” with a companion star in a binary system. When this happens, circumstellar material will form around the star and will eventually be hit by the ejected material in the explosion.
In a galaxy, there are an enormous number of stars. If you think that there are at least two trillion observed galaxies, you can picture what a vast playground of discoveries scientists play with every day. Although not all stars end with an explosion, the proportion is large enough to allow scientists to confirm and study their shell structure and chemical composition.
The luminosity (brightness) of the new discovery in terms of timeframe and behaviour was similar to other known and well-studied stellar explosions. The chemical signatures discovered in their electromagnetic spectra (colours) and their appearance over time pointed to a thick inner stellar layer expelled by the star.
Eta Carinae may become a supernova similar to the most recent explosion.
This was then struck by material left in the star and expelled during the explosion. However, some traces of light elements were also present, in direct clash with the heavy elements as they should be found in stellar layers far apart from each other.
The astronomers measured the layer velocity to be around 1,000 km/s, consistent with that of massive stars called Wolf-Rayet, previously identified as progenitor stars of similar stellar explosions. They modelled both the luminosity behaviour and electromagnetic spectra composition and found the thick layer, rich in silicon and sulphur, to be more massive than that of our Sun but still less than the material ejected in the final explosion.
Heavy elements
The new discovery, the first of its kind, revealed the formation site of the heavy elements and confirmed with direct observations the complete sequence of concentric shells in massive stars. Some stars develop internal “onion-like” layers of heavier elements produced by nuclear fusion, which are called shells. The latest findings have left the astronomy community with new questions: what process can strip stars down to their inner shells? Why do we see lighter elements if the star has been stripped to the inner shells?
This new supernova type is clearly another curveball thrown by the Universe to the scientists. The energy and the layers composition cannot be explained with the current massive star evolution theory. In the framework of mass loss driven by wind (a continuous stream of particles from the star), a star stripped down to the region where heavy elements form is difficult to explain.
A possible explanation would require invoking an unusual scenario where SN2021yfi actually consists of two stars – a binary system. In this case, the stripping down of the principal star would be carried out by a strong stellar wind produced by the companion star.
An even more exotic explanation is that SN2021yfi is an extremely massive star, up to 140 times that our Sun. Instabilities in the star would release very massive shells at different stages of its evolution. These shells would eventually collide with each other while the star collapsed into a black hole, leading to no further material released into the cosmos during the explosion.
To improve our understanding of stellar evolution, we would need to observe more such objects. But our comprehension could be limited by their intrinsic rarity – because the possibility of finding another explosion like SN2021yfi is less than 0.00001%.
The James Webb Space Telescope (JWST) has observed the interstellar visitor 3I/ATLAS for the first time. The powerful space telescope trained its infrared vision and its Near-Infrared Spectrograph instrument (NIRspec) on the comet on Aug. 6, 2025.
Discovered on July 1 by the ATLAS (Asteroid Terrestrial-impact Last Alert System) survey telescope, 3I/ATLAS is just the third-ever object found drifting through our solar system that is believed to have originated from around another star. The other two interstellar intruders were 1I/’Oumuamua, discovered in 2017, and 2I/Borisov, detected in 2019.
The JWST follows in the footsteps of the Hubble Space Telescope and the SPHEREx Observatory, both of which have already observed 3I/ATLAS as it passes through the solar system. This investigation aims to uncover characteristics of 3I/ATLAS, including its size, physical properties, and, importantly, its chemical makeup.
In a preprint paper describing their investigation of 3I/ATLAS, a team of astronomers that observed the comet with the JWST explains that studying comets like this from other star systems helps to study what conditions were like in those systems as they were forming. Those results can then be compared to what scientists have learned about the conditions around the sun 4.6 billion years ago, when the planets, asteroids, and comets of the solar system were forming.
When comets approach the sun and are warmed by its heat, frozen materials within them are transformed from solids straight into gases. This results in gases escaping, a process called “outgassing,” creating the characteristic tail and halo, or “coma,” of a comet.
As expected, 3I/ATLAS is outgassing as it approaches the sun, and astronomers have used the JWST and its NIRSpec instrument to identify carbon dioxide, water, water ice, carbon monoxide, and the smelly gas carbonyl sulfide in its coma.
What wasn’t expected, however, was the highest ratio of carbon dioxide to water ever observed in a comet. This could reveal more about the conditions in which 3I/ATLAS formed.
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3I/ATLAS traveling through a background of stars as seen by the ground-based telescopes of the Las Cumbres Observatory. (Image credit: ESA)
The abundance of carbon dioxide in the coma of 3I/ATLAS could indicate that the interstellar comet has a heart that is intrinsically rich in carbon dioxide. This could imply that the comet contains ices that were exposed to much higher levels of radiation than comets in the solar system have been exposed to.
Alternatively, the team suggests this high carbon dioxide content could indicate that 3I/ATLAS may have formed in a specific site called the “carbon dioxide ice line” within the swirling cloud of matter, or “protoplanetary disk,” that surrounded its stellar parent. This is defined as the point at which the temperature around an infant star or “protostar” falls low enough to allow carbon dioxide to change from a gas to a solid.
Furthermore, the low abundance of water vapor in the coma of 3I/ATLAS could indicate that there is something within the comet that is inhibiting heat from penetrating the icy core of the comet. This would hinder the amount of water transforming from ice into gas relative to the transformation rate of carbon dioxide and carbon monoxide.
These new findings build upon the wealth of fascinating data being collected about 3I/ATLAS. This includes the previous discovery that the interstellar comet could actually be around 7 billion years old, meaning it is the oldest comet ever seen and around 3 billion years older than the solar system.
The team behind that prior research on the comet came to this conclusion when they examined the steep trajectory of 3I/ATLAS through the solar system. This indicated that it comes from the Milky Way’s “thick disk” of stars, a region of our galaxy much more ancient than the “thin disk” within which the sun was born.
One thing is certain: the study of 3I/ATLAS will continue until the comet returns to interstellar space with considerably fewer secrets than it carried into the solar system. And the JWST is set to be heavily involved in the unraveling of this mystery.
Researchers at the University of Sharjah, UAE, have developed a new way to turn shrimp waste into a useful carbon material that can capture carbon dioxide.
This innovation offers a two-for-one solution, addressing waste management and helping to mitigate climate change.
The new waste-to-carbon technology taps into discarded shrimp parts like shells, heads, and guts. Through extensive processing, the waste is turned into activated carbon.
The researchers state that this material is highly effective at capturing CO₂, making it a strong option for industrial carbon capture.
“Our study turns shrimp waste into a high-performance carbon product. This addresses the environmental challenges posed by seafood waste and contributes to global efforts to reduce greenhouse gas emissions and climate change mitigation,” said Dr. Haif Al-Jomard, the lead researcher.
Extensive treatment process
The scale of the problem is significant. The global processing of shrimp, lobster, and crab shells produces up to eight million tons of waste annually, a large portion of which is discarded in landfills.
The research specifically focused on white shrimp shells and heads sourced from Souq Al Jubail in Sharjah, United Arab Emirates, with the shrimp originally coming from Oman.
Before being used in the process, the team ensured the waste was thoroughly cleaned and air-dried.
The press release detailed a multi-step process for converting shrimp waste into a powerful CO₂-capturing material.
First, shrimp waste undergoes pyrolysis, a high-temperature process that transforms it into biochar. This biochar is then put through a series of treatments, including acid treatment, chemical activation, and ball milling.
The extensive process results in a highly effective final product—activated carbon—that captures carbon dioxide and maintains its strong performance and stability over many use cycles.
“This approach offers a cost-effective route to producing activated carbon, turning a problematic waste stream into a high-performance, efficient, and environmentally friendly product with wide-ranging applications,” said Professor Chaouki Ghenai, co-author and expert in Sustainable and Renewable Energy at the University of Sharjah.
Various uses of material
The applications for activated carbon made from shrimp waste extend beyond just capturing carbon.
The material could be used for purifying air and water, recovering solvents, extracting gold, and even for certain medical uses.
Within the carbon capture, utilization, and storage (CCUS) field, the material is particularly promising for adoption by major industries like power generation, cement and steel manufacturing, and petrochemicals.
This approach, the researchers explain, is a perfect example of a circular economy.
It improves resource efficiency and waste valorization by cutting down on consumption and transforming what would be waste into a highly useful resource.
“Our findings validate a scalable and sustainable strategy for shrimp waste valorization,” the team noted in the press release.
“The combined thermal, chemical, and mechanical treatments of shrimp waste enhance both the textural and chemical properties of the final activated carbon material, making it a viable solution for climate change mitigation,” it added.
Adopting it could be important in reducing greenhouse gases and mitigating climate change.
The findings were published in the journal Nanoscale.
One snake, two venoms — and the wrong antivenom could make the difference between life and death. Credit: Shutterstock
Researchers have uncovered a hidden split in the venom of Australia’s deadly Eastern Brown Snake.
Southern populations create rock-solid blood clots, while northern snakes produce fragile clots that collapse almost instantly — two very different paths to the same deadly outcome. This discovery raises urgent concerns about whether current antivenoms, made from pooled venoms of unclear origin, can fully protect patients across regions.
Antivenom Effectiveness Questioned
A new study from the University of Queensland suggests that the antivenom used to treat Eastern Brown Snake bites may not always provide full protection, leading researchers to review hospital records.
The project was led by Professor Bryan Fry of UQ’s School of the Environment, who, along with his team, analyzed the blood-clotting toxins found in the venom of every Australian brown snake species.
Clotting Patterns: Rock-Solid vs Fragile
“We discovered not all brown-snake venoms are the same – meaning that lifesaving antivenom may need an urgent upgrade,” Professor Fry said.
“Some venoms formed a rock-solid clot in blood, while others spun up a rapid but flimsy web of clots that shredded almost instantly.
“Both venoms can kill, but they do it in completely different ways.”
An Australian Eastern Brown Snake (Pseudonaja textilis). Credit: Stewart Macdonald
Southern vs Northern Eastern Browns
To investigate further, the researchers used a technique called thromboelastography, which measures blood coagulation. Their results revealed that Eastern Brown Snakes (Pseudonaja textilis) from southern Australia produce a taipan-like venom that creates a firm, lasting clot.
In contrast, venom from northern Eastern Brown Snakes and from all other brown snake species generated clots that were weak and easily destroyed, although they formed at remarkable speed.
“Our data shows the effect on blood of an Eastern Brown Snake bite in northern areas and a bite in southern Australia are chalk and cheese,” Professor Fry said.
Rethinking Hospital Records
“Currently, Australia’s brown-snake antivenom is produced using a pool of venom of unstated geographic origin.
“If it doesn’t have both northern and southern Eastern Brown Snake venom, coverage could be patchy, and the antivenom efficacy could vary widely.
“Clinical reports have all brown snake bite cases together regardless of species or location, so any differences for the southern population versus all other brown snakes could be obscured.
Precision Toxicology on the Horizon
“Our next step is to go back through hundreds of hospital charts to ascertain if there is a difference, which we can do because the southern strong-clot lineage lives where no other brown snake occurs.
“We can re-code every reported bite by geography and tease apart the clotting patterns between the strong and weak clotting types of brown snakes.
“We will also urgently test the available human and veterinary antivenoms to see if the differences in venom biochemistry are mirrored by variations in antivenom efficacy.
“While existing antivenoms have saved lives, with new information we can move to precision toxicology, matching the right antivenom to the right snake, and ultimately, to the right patient.”
Genetic Clues to Venom Evolution
Professor Fry’s team is also sequencing the venom genes to pinpoint the mutations responsible for the differences in northern and southern Eastern Brown Snakes.
“We showed the geographic difference in venom effect overlays with a genetic divide within the Eastern Brown Snake,” he said.
“Our research demonstrates how diet steers venom evolution, because the southern populations consume more reptiles than the northern populations, which eat more mammals.
“By appreciating both the evolutionary fine-tuning and the clinical outcomes of these venoms, we can better tailor our medical responses.”
The research paper has been published in Toxins.
Reference: “X Marks the Clot: Evolutionary and Clinical Implications of Divergences in Procoagulant Australian Elapid Snake Venoms” by Holly Morecroft, Christina N. Zdenek, Abhinandan Chowdhury, Nathan Dunstan, Chris Hay and Bryan G. Fry, 17 August 2025, Toxins. DOI: 10.3390/toxins17080417
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Bearded dragons are famous for their ability to change sex depending on heat and genes. Two new genome projects have revealed the likely master gene, Amh, behind this switch — finally solving a reptile mystery that has baffled scientists for years. Credit: Shutterstock
Scientists have finally cracked one of the strangest mysteries in reptile biology: how bearded dragons decide their sex.
Two separate research teams have now released near-complete reference genomes of the central bearded dragon (Pogona vitticeps), a lizard species that ranges widely across central eastern Australia and is also a favorite pet in Europe, Asia, and North America.
What makes this reptile stand out is its unusual system of sex determination: whether it develops as male or female depends not only on its chromosomes but also on the temperature at which its eggs are incubated. Because of this dual mechanism, the species has long served as a model for studying how sex is determined in animals.
With major advances in genome sequencing, scientists have finally pinpointed a specific region of the genome and identified a likely master sex-determining gene tied to male development. The fact that two independent groups reached this conclusion using different methods gives the discovery much greater weight.
In bearded dragons, both genetic and environmental influences shape sex. Unlike most species, where sex is set entirely by chromosomes, these lizards can override genetics under certain conditions. When eggs carrying male chromosomes are exposed to high incubation temperatures, the hatchlings can develop into fully functional females.
Unraveling the Z and W Chromosomes
Like many reptiles and birds, bearded dragons use a ZZ/ZW system of sex chromosomes: males have two matching ZZ chromosomes, while females have one Z and one W. The situation becomes more complex because ZZ individuals that are genetically male can still become females if incubated at warm enough temperatures, without relying on the W chromosome or its associated genes.
Recent progress in ultra-long nanopore sequencing has made it possible to assemble the sex chromosomes from telomere to telomere (T2T) and clearly identify the regions that do not recombine. This makes it much easier to narrow down the list of possible sex-determining genes. The technology also allows researchers to better distinguish the maternal and paternal versions of the genome, enabling direct comparisons of the Z and W chromosomes to detect gene loss or functional differences that could explain how sex is controlled in the species.
Example of an Australian central bearded dragon (Pogona vitticeps). Credit: Duminda Dissanayake
Two Teams, Two Technologies, One Discovery
The first paper from researchers from BGI, Chinese Academy of Sciences and Zhejiang University, uses DNBSEQ short-reads combined with long-reads from the new CycloneSEQ nanopore sequencer, this being the first animal genome published using this technology. Generation of the second genome was led by researchers from the University of Canberra with funding from Bioplatforms Australia, the Australian Research Council and PacBio Singapore, and with contributions to analyses from researchers of the Australian National University, Garvan Institute for Medical Research, University of New South Wales and CSIRO alongside Universitat Autònoma de Barcelona (UAB) in Spain. This assembly uses PacBio HiFi, ONT ultralong reads and Hi-C sequencing.
Having reference genomes published using these two different technologies allows a like-for-like comparison between the ONT and CycloneSEQ technologies for the first time. Both technologies also complement each other by investigating the sex determination question using different approaches.
The first genome sequenced a ZZ male central bearded dragon to characterize the whole Z sex chromosome for the first time while the second assembled the genome of a female ZW individual. The new nanopore sequencer also enabled the recovery of around 124 million base pairs of previously undescribed and missing sequences (nearly 7% of the genome), which included numerous genes and regulatory elements to better elucidate the complicated sex determination system.
Pinpointing the Master Sex Gene
Both projects assembled 1.75 Gbp genome assemblies of exceptionally high quality to assemble all but one of the telomeres, and only a few gaps remained mostly located in the microchromosomes. Using this data showed the Z and W specific sex chromosomes were assembled into single scaffolds, and a “pseudo-autosomal region” (PAR) where the sex chromosomes pair and recombine was also detected on chromosome 16.
The sequencing of the male dragon by the BGI team looked for genes specific to Z but not the W chromosomes, and Amh and Amhr2 (the Anti-Müllerian hormone gene and its receptor) plus Bmpr1a were determined as strong candidates for the sex determining genes in this species. The sequencing of the female dragon by the Australian-led team pinpointed to the same candidate Sex Determination Region (SDR) of their dragon genome, and also highlighted Amh and Amhr2 as the likely candidate genes.
Studying the expression in different developmental stages found Amh had significant male-biased expression patterns making it the most likely candidate as the master sex-determining gene. The differential expression of another sex-related gene Nr5a1 in the PAR suggests that the story may be more complicated, as Nr5a1 encodes a transcription factor with binding sites on the Amh promoter region.
Unlike many fish that enlist Amh-like genes in sex determination, the autosomal copies of Amh and its receptor gene Amhr2 remain intact and functional. It could be that sex is determined by some form of caucus among genes on the sex chromosomes of the bearded dragon moderated by their residual autosomal copies.
A Landmark Find: Amh Emerges as Candidate
The main highlight of these assemblies is therefore the discovery of genetic elements central to male sexual differentiation in vertebrates, on the sex chromosomes. The genes Amh and those coding its receptor AMHR2 have been copied to the Z chromosome in the non-recombining region, and so are obvious candidates for the master sex determining gene working via a dosage-based mechanism in this species, a discovery that has eluded discovery for so many years. No master sex determining gene akin to Sry in mammals or Dmrt1 in birds has to date been discovered in any reptile species. This new work provides a clear candidate in Amh, which is present in double dose in the ZZ male and single dose in the ZW female.
Arthur Georges from University of Canberra and senior author on the second paper says on the utility of this work: “We anticipate accelerated research in other areas arising from these newly available assemblies, such as cranial development, brain development, behavioural studies, gene-gene and gene-environment interactions in comparative studies of vertebrate sex determination and in many other areas looking for a well-supported squamate model against which to compare with their model species be it mouse, human or bird.”
China’s Rapid Rise in Genome Technology
“I never cease to be amazed by the rapidity of progress of Chinese science. In relatively few years, BGI and its companion enterprises have developed sequencing technologies that deliver outcomes as good, and throughput and cost effectiveness that is better, than competing technologies on the market. These genome assemblies are testimony to that level of achievement.”
Qiye Li from BGI and senior author on the first paper Lead author of the Chinese project explains their rationale for using this approach: “We decided to start working on the bearded dragon genome last year as the first animal genome for this new sequencer because it was the Year of the Dragon in China. Benefiting from the unbiased long-reads provided by the CycloneSEQ sequencer, we readily obtained a highly contiguous genome assembly and resolved highly repetitive and high-GC regions that were traditionally challenging for assembly. The two reference genomes, derived from opposite sex and generated by different technologies, are indeed complementary to each other. I am excited that both genomes pinpoint the key role of AMH signaling in sex determination in this species. But how did the sex chromosomes arise? We anticipate that additional high‑quality genomes from related species will further elucidate the evolutionary origin of the ZW system and complete the story.”
Confidence Strengthened by Independent Proof
Having two separate projects finding the same key candidate master genes independently of each other greatly increases the confidence in these findings. And openly sharing all of the data allows others to build upon this work, especially as the exact role of some of the other contributing transcription factors linked to sex determination is not yet fully resolved. The generation of these two new high quality genome assemblies however, is a massive step forward towards understanding the complete story of sex determination in this species.
References:
“A near-complete genome assembly of the bearded dragon Pogona vitticeps provides insights into the origin of Pogona sex chromosomes” by Qunfei Guo, Youliang Pan, Wei Dai, Fei Guo, Tao Zeng, Wanyi Chen, Yaping Mi, Yanshu Zhang, Shuaizhen Shi, Wei Jiang, Huimin Cai, Beiying Wu, Yang Zhou, Ying Wang, Chentao Yang, Xiao Shi, Xu Yan, Junyi Chen, Chongyang Cai, Jingnan Yang, Xun Xu, Ying Gu, Yuliang Dong and Qiye Li, 19 August 2025, GigaScience. DOI: 10.1093/gigascience/giaf079
“A near telomere-to-telomere phased genome assembly and annotation for the Australian central bearded dragon Pogona vitticeps” by Hardip R Patel, Kirat Alreja, Andre L M Reis, J King Chang, Zahra A Chew, Hyungtaek Jung, Jillian M Hammond, Ira W Deveson, Aurora Ruiz-Herrera, Laia Marin-Gual, Clare E Holleley, Xiuwen Zhang, Nicholas C Lister, Sarah Whiteley, Lei Xiong, Duminda S B Dissanayake, Paul D Waters and Arthur Georges, 19 August 2025, GigaScience. DOI: 10.1093/gigascience/giaf085
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In 2023, NASA’s OSIRIS-REx mission brought something rare back to Earth: samples from Bennu, an asteroid about 1,600 feet across. The mission took seven years and returned with pieces of rock older than Earth itself.
The dirt and rock collected from Bennu weren’t just space souvenirs. They held a story billions of years old, written in dust from other stars, minerals shaped by water, and scars from micrometeorite hits.
What scientists are now learning from this ancient rubble is changing how we think about where planets come from – and even where life’s building blocks may have formed.
Asteroid Bennu’s shattered origin
Bennu didn’t form as one solid rock. It’s a collection of fragments from a much older parent asteroid that once orbited between Mars and Jupiter.
The parent body was made of material from all over the early solar system – including matter formed near the Sun, far beyond the giant planets, and even outside of our solar system entirely.
The mix of materials suggests Bennu’s parent asteroid formed in the outer solar system – maybe even beyond Jupiter and Saturn – and later shattered in a collision.
After that, pieces reassembled into new bodies, possibly more than once. Bennu is one of those reassembled objects, holding clues from every phase of the long journey.
Stardust and interstellar clues
Researchers analyzing the Bennu samples have found an abundance of stardust – tiny grains of material that predate the Sun. These grains are easy to spot in the lab thanks to their unusual isotopic patterns, and they’re incredibly rare to find intact on Earth.
“Those are pieces of stardust from other stars that are long dead, and these pieces were incorporated into the cloud of gas and dust from which our solar system formed,” said Jessica Barnes, associate professor at the University of Arizona’s Lunar and Planetary Laboratory.
“In addition, we found organic material that’s highly anomalous in their isotopes and that was probably formed in interstellar space, and we have solids that formed closer to the Sun, and for the first time, we show that all these materials are present in Bennu.”
Asteroid Bennu once had water
The samples also reveal that Bennu once had water – or at least its parent did. Another team studying the rocks detected evidence that the minerals within them had undergone chemical changes in contact with liquid water. These processes likely occurred at about 77°F (25°C), roughly room temperature on Earth.
“We think that Bennu’s parent asteroid accreted a lot of icy material from the outer solar system, which melted over time,” said Tom Zega, director of the Kuiper-Arizona Laboratory who co-led the study.
The melting could’ve been caused by leftover heat from the asteroid’s formation, radioactive decay, or even more asteroid collisions.
“Now you have a liquid in contact with a solid and heat – everything you need to start doing chemistry,” Zega said. “The water reacted with the minerals and formed what we see today: samples in which 80% of minerals contain water in their interior, created billions of years ago when the solar system was still forming.”
This kind of water-driven chemistry could be how life’s ingredients started coming together. Finding it in an asteroid this old helps scientists understand where and when those conditions first appeared.
Beaten up by space
Even after it formed, Bennu’s story kept going. A third study revealed that Bennu’s surface has taken a beating. It’s marked by tiny craters and specks of molten rock – damage caused by speeding micrometeorites and the sun’s solar wind.
Together, these effects are called space weathering. They happen fast and constantly on Bennu, since it doesn’t have an atmosphere for protection. The researchers found that this weathering changes surface materials more quickly than expected.
The damage doesn’t just affect what Bennu looks like. It also changes what scientists can see with telescopes and space cameras, because it alters the color and texture of the surface.
Significance of the Bennu samples
Asteroids that hit the ground become meteorites, and we’ve found many pieces of them before. However, many asteroids burn up in the atmosphere.
The ones that survive often sit out in the open too long, reacting with Earth’s air and water. The contamination makes them harder to study.
“And those that do make it to the ground can react with Earth’s atmosphere, particularly if the meteorite is not recovered quickly after it falls,” said one of the scientists involved. “Which is why sample return missions such as OSIRIS-REx are critical.”
Not just another space rock
NASA’s OSIRIS-REx spacecraft collected the Bennu samples in space and sealed them immediately, giving scientists a clean look at raw, untouched asteroid material.
The purity of the samples provides a sharper view of the solar system’s early chemistry – and a better shot at answering big questions about where we came from.
Bennu may look like a rubble pile floating in space, but it’s much more than that. It is a time capsule that holds a record of when our solar system was still forming. It carries pieces of other stars, the fingerprints of flowing water, and the scars of a long, violent history.
Image credit: NASA/Goddard/University of Arizona
The full study was published in the journal Nature Astronomy.
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Worker bees feeding in the lab, Oxford Bee Lab. Credit: Caroline Wood
Scientists have created a groundbreaking bee “superfood” by engineering yeast to produce six essential sterols normally found in pollen.
Colonies given this lab-made diet reared up to 15 times more young than those on standard feeds, thriving with a nutrient profile almost identical to naturally foraged diets. The breakthrough offers a sustainable way to restore bee health at a time when pollinator populations are collapsing, threatening food security worldwide.
Breakthrough Bee Superfood Could Halt Colony Declines
A team of researchers led by the University of Oxford, working with Royal Botanic Gardens Kew, the University of Greenwich, and the Technical University of Denmark, has developed a promising approach to address the alarming decline of honeybees. Their work centers on a specially engineered dietary supplement that replicates vital compounds normally obtained from plant pollen. When tested, this supplement was shown to dramatically boost colony reproduction. The findings were released on August 20 in the journal Nature.
Beekeeper Dan Etheridge with a bee frame. Credit: Caroline Wood.
Climate Change, Farming, and Bee Nutrition Crisis
Honeybees are struggling in part because climate change and modern farming practices have reduced the variety of flowers they rely on. Pollen makes up the bulk of a bee’s diet and contains lipids known as sterols that are essential for healthy growth and development. With natural pollen supplies increasingly scarce, beekeepers have turned to artificial substitutes. These products, typically made from protein flour, sugars, and oils, provide calories but do not contain the sterols bees require, leaving them nutritionally deficient.
In this study, the scientists genetically modified the yeast Yarrowia lipolytica so it could generate a precise blend of six sterols critical to bee health. They then incorporated the yeast into experimental diets and tested them in controlled feeding trials lasting three months. The colonies were housed in enclosed glasshouses to ensure the bees consumed only the specially formulated diets.
Rearing cage honeybees in the lab, Oxford Bee Lab. Credit: Caroline Wood.
Key Findings:
By the end of the study period, colonies fed with the sterol-enriched yeast had reared up to 15 times more larvae to the viable pupal stage, compared with colonies fed control diets.
Colonies fed with the enriched diet were more likely to continue rearing brood up to the end of the three-month period, whereas colonies on sterol-deficient diets ceased brood production after 90 days.
Notably, the sterol profile of larvae in colonies fed the engineered yeast matched that found in naturally foraged colonies, suggesting that bees selectively transfer only the most biologically important sterols to their young.
Synthetic Biology Unlocks Nutritional Solutions
Senior author Professor Geraldine Wright (Department of Biology, University of Oxford), said: “Our study demonstrates how we can harness synthetic biology to solve real-world ecological challenges. Most of the pollen sterols used by bees are not available naturally in quantities that could be harvested on a commercial scale, making it otherwise impossible to create a nutritionally complete feed that is a substitute for pollen.”
Lead author Dr. Elynor Moore (Department of Biology, University of Oxford at the time of the study, now Delft University of Technology) added: “For bees, the difference between the sterol-enriched diet and conventional bee feeds would be comparable to the difference for humans between eating balanced, nutritionally complete meals and eating meals missing essential nutrients like essential fatty acids. Using precision fermentation, we are now able to provide bees with a tailor-made feed that is nutritionally complete at the molecular level.”
Before this work, it was unclear which of the diverse sterols in pollen were critical for bee health. To answer this, the researchers chemically assessed the sterol composition of tissue samples harvested from pupae and adult bees. This required some extraordinarily delicate work; for instance, dissecting individual nurse bees to separate the guts. The analysis identified six sterol compounds that consistently made up the majority in bee tissues: 24-methylenecholesterol, campesterol, isofucosterol, β-sitosterol, cholesterol, and desmosterol.
Using CRISPR-Cas9 gene editing, the researchers then engineered the yeast Yarrowia lipolytica to produce these sterols in a sustainable and affordable way. Y. lipolytica was selected since this yeast has a high lipid content, has been demonstrated as food-safe, and is already used to supplement aquaculture feeds. To produce the sterol-enriched supplement, engineered yeast biomass was cultured in bioreactors, harvested, then dried into a powder.
Co-author Professor Irina Borodina (The NNF Center for Biosustainability, Technical University of Denmark) said: “We chose oleaginous yeast Yarrowia lipolytica as the cell factory because it is excellent at making compounds derived from acetyl-CoA, such as lipids and sterols, and because this yeast is safe and easy to scale up. It is used industrially to produce enzymes, omega-3 fatty acids, steviol glycosides as calorie-free sweeteners, pheromones for pest control, and other products.”
One of the Oxford Bee Lab’s hives. Credit: Caroline Wood
Protecting Crops, Biodiversity, and Wild Bees
Pollinators like honeybees contribute to the production of over 70% of leading global crops. Severe declines – caused by a combination of nutrient deficiencies, climate change, mite infestations, viral diseases, and pesticide exposure – poses a significant threat to food security and biodiversity. For instance, over the past decade, annual commercial honey bee colony losses in the U.S have typically ranged between 40 and 50%, and could reach 60 to 70% in 2025. This new engineered supplement offers a practical means to enhance colony resilience without further depleting natural floral resources. Since the yeast biomass also contains beneficial proteins and lipids, it could potentially be expanded into a comprehensive bee feed.
Co-author Professor Phil Stevenson (RBG Kew and Natural Resources Institute, University of Greenwich) added: “Honey bees are critically important pollinators for the production of crops such as almonds, apples, and cherries, and so are present in some crop locations in very large numbers, which can put pressure on limited wildflowers. Our engineered supplement could therefore benefit wild bee species by reducing competition for limited pollen supplies.”
A Game-Changer for Farmers and Food Security
Danielle Downey (Executive Director of honeybee research nonprofit Project Apis m., not affiliated with the study) said: “We rely on honey bees to pollinate one in three bites of our food, yet bees face many stressors. Good nutrition is one way to improve their resilience to these threats, and in landscapes with dwindling natural forage for bees, a more complete diet supplement could be a game-changer. This breakthrough discovery of key phytonutrients that, when included in feed supplements, allow sustained honey bee brood rearing has immense potential to improve outcomes for colony survival, and in turn the beekeeping businesses we rely on for our food production.”
Next Steps: Field Trials and Wider Applications
Whilst these initial results are promising, further large-scale field trials are needed to assess long-term impacts on colony health and pollination efficacy. Potentially, the supplement could be available to farmers within two years.
This new technology could also be used to develop dietary supplements for other pollinators or farmed insects, opening new avenues for sustainable agriculture.
Reference: “Engineered yeast provides rare but essential pollen sterols for honeybees” by Elynor Moore, Raquel T. de Sousa, Stella Felsinger, Jonathan A. Arnesen, Jane D. Dyekjær, Dudley I. Farman, Rui F. S. Gonçalves, Philip C. Stevenson, Irina Borodina and Geraldine A. Wright, 20 August 2025, Nature. DOI: 10.1038/s41586-025-09431-y
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While most of us take the ground beneath our feet for granted, written within its complex layers, like the pages of a book, is Earth’s history. Our history.
Research shows there are little-known chapters in that history, deep within Earth’s past. In fact, Earth’s inner core appears to have another even more inner core within it.
“Traditionally we’ve been taught the Earth has four main layers: the crust, the mantle, the outer core and the inner core,” Australian National University geophysicist Joanne Stephenson explained in 2021.
Related: Earth’s Inner Core Is Mysteriously Changing Shape, Study Reveals
Our knowledge of what lies beneath Earth’s crust has been inferred mostly from what volcanoes have divulged and what seismic waves have whispered.
From these indirect observations, scientists have calculated that the scorchingly hot inner core, with temperatures surpassing 5,000 degrees Celsius (9,000 Fahrenheit), makes up only 1 percent of Earth’s total volume.
But a few years ago, Stephenson and colleagues found evidence Earth’s inner core may actually have two distinct layers.
“It’s very exciting – and might mean we have to re-write the textbooks!” Stephenson explained at the time.
The team used a search algorithm to trawl through and match thousands of models of the inner core with observed data across many decades about how long seismic waves take to travel through Earth, gathered by the International Seismological Centre.
Differences in seismic wave paths through layers of Earth. (Stephenson et al., Journal of Geophysical Research: Solid Earth, 2021)
So what’s down there? The team looked at some models of the inner core’s anisotropy – how differences in the make-up of its material alters the properties of seismic waves – and found some were more likely than others.
While some models suggest the material of the inner core channels seismic waves faster parallel to the equator, others indicate the mix of materials allows for faster waves more parallel to Earth’s rotational axis. Even then, there are arguments about the exact degree of difference at certain angles.
The study here didn’t show much variation with depth in the inner core, but it did find there was a change in the slow direction to a 54-degree angle, with the faster direction of waves running parallel to the axis.
Earth’s inner core may actually have two distinct layers. (alexlmx/Canva Pro)
“We found evidence that may indicate a change in the structure of iron, which suggests perhaps two separate cooling events in Earth’s history,” Stephenson said.
“The details of this big event are still a bit of a mystery, but we’ve added another piece of the puzzle when it comes to our knowledge of the Earth’s inner core.”
These findings may explain why some experimental evidence has been inconsistent with our current models of Earth’s structure.
The presence of an innermost layer has been suspected before, with hints that iron crystals that compose the inner core have different structural alignments.
“We are limited by the distribution of global earthquakes and receivers, especially at polar antipodes,” the team writes in their paper, explaining the missing data decreases the certainty of their conclusions.
But their conclusions align with other studies on the anisotropy of the innermost inner core.
Future research may fill in some of these data gaps and allow scientists to corroborate or contradict their findings, and hopefully translate more stories written within this early layer of Earth’s history.
This research was published in the Journal of Geophysical Research.
An earlier version of this article was published in March 2021.
The smallest magnetic loops ever seen in the sun’s corona — imaged for the first time by the National Science Foundation’s Daniel F. Inouye Solar Telescope — could be the bottom floor of the machinery that powers the ferocious flares that routinely blast out from our star.
“It’s a landmark moment in solar science,” said Cole Tamburri of the University of Colorado, Boulder, in a statement. “We’re finally seeing the sun at the scales it works on.”
Basically, solar flares are produced when magnetic field lines that loop through the sun’s outer atmosphere, the corona, grow taut and snap, releasing energy before reconnecting once again. This has been known for some time, but the details involved in magnetic reconnection and solar flares, however, still require some working out. One big question has been: How small can these coronal loops go, and what role could these miniature loops play in powering solar flares?
The full version of DKIST’s image of narrow coronal loop strands. The image is about 4 Earth-diameters on each side. (Image credit: NSF/NSO/AURA)
The Daniel K. Inouye Solar Telescope (DKIST), operated by the National Science Foundation’s (NSF) National Solar Observatory, has now imaged hundreds of coronal loop strands that are just 29.95 miles (48.2 kilometers) wide on average, and some could be as thin as 13 miles (21 kilometers). These are right on the limit of the DKIST’s resolution, which is itself more than 2.5 times sharper than the next best solar telescope.
“Before Inouye, we could only imagine what this scale looked like,” said Tamburri. “Now we can see it directly.”
The forest of small loops was seen in hydrogen-alpha light by DKIST’s Visible Broadband Imager in the aftermath of an X-class flare — the most powerful category of flare that the sun can unleash — seen on Aug. 8, 2024.
“This is the first time the Inouye Solar Telescope has ever observed an X-class flare,” said Tamburri. “These flares are among the most energetic events our star produces, and we were fortunate to catch this one under perfect observing conditions.”
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The Daniel K. Inouye Solar Telescope. (Image credit: NSF/NSO/AURA)
How these small loops play into the process of magnetic reconnection isn’t yet clear, but now that scientists know that they are there, they can start to fit them into their models of how the sun operates. It may be that these small loops are a fundamental building block of the sun’s magnetic architecture that creates the flares.
“If that’s the case, we’re not just resolving bundles of loops, we’re resolving individual loops for the first time,” said Tamburri. “It’s like going from seeing a forest to suddenly seeing every single tree.”
The image of the coronal loops shows the power of the Inouye Solar Telescope, and Tamburri himself is supported by the Inouye Solar Telescope Ambassador Program, which is funded by the NSF and aims to give young researchers expertise they can take into the broader solar community as they further their careers.
However, storm clouds are gathering on the horizon. The budget proposed by the US government for the fiscal year 2026 would see the Inouye Solar Telescope receive a massive shortfall in funding, down from $30 million to $13 million, which the director of the NSF’s National Solar Observatory, Christoph Keller, says is not enough to keep the Inouye Solar Telescope open.
Should the telescope have to close, it wouldn’t just be its spectacular images of the sun that we will lose, but also the expertise of the researchers that it helps train. The loss of the telescope and its scientists could damage future solar research for years to come. However, if this is the Inouye Telescope’s last hurrah, then it is going out on a high.
Tamburri and his team describe their observations of the small flares in a paper published on Aug. 25 in The Astrophysical Journal Letters.
