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British Firms Poised to Seize a Major Share of the AI Chip Market

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TThe UK holds a unique and advantageous position to contribute significantly in the new era of artificial intelligence, provided it seizes the chance to establish the production of millions of computer chips, an area that is often misunderstood.

AI technology demands a vast quantity of chips, and a collaborative national initiative could fulfill up to 5% of the global requirement.

Our legacy in chip design is unparalleled, beginning with the first general-purpose electronic computer, the initial electronic memory, and the first parallel computing system. Presently, Arm, based in Cambridge, is a prominent player that designs over 90% of the chips found in smartphones and tablets worldwide.

Given this background, it is certainly plausible that British companies can capture a notable share of the AI chip market. A target of 5% is both conservative and achievable. Our distinguished universities, a flourishing foundational AI company like DeepMind, and a strong innovation ecosystem equip the UK with the tangible resources necessary to compete.

The potential gains are tremendous. The global market for AI chips is expected to soar to $700 billion (£620 billion) annually by 2033, surpassing the entire current semiconductor market. Achieving that 5% share would translate to an influx of $35 billion in new revenue and the creation of thousands of high-paying jobs.

AI is set to transform not only the economy but also societal structures and security. Unfortunately, many do not grasp where its true value and strategic influence lie.

In this contemporary gold rush, real wealth is accessible not only to those mining digital gold but also to those who provide the tools for the task. I witnessed this firsthand from 1997 to 2006 when Gordon Moore and Andy Grove helped establish Intel’s board and founded the company in California. They set the groundwork for the first technology revolution, much like Nvidia is doing today on an even larger scale.

UK engineers, intellects, businesses, and investors excel in this domain. However, government collaboration is crucial.

While consumers are captivated by the generative marvels of OpenAI, the true market winner is Nvidia, the entity that provides the advanced chips facilitating such achievements. OpenAI’s estimated value stands at merely 1/10th that of Nvidia. AMD, a semiconductor design company, holds a distant second place, while emerging firms like Cerebras and TenTrent strive for a share of the market.

All AI models and applications, ranging from autonomous robots to real-time translation services, depend heavily on advancements in chip technology. Chips are the new oil of the digital economy, dictating the speed and efficiency with which future applications can be developed. Currently, the only major players in the AI field seeing true profitability are chip manufacturers.

Concerns have arisen that China may commoditize AI chips similar to its approach with solar technology, leading to dramatic price fluctuations and undercutting existing companies. The situation is more complex. U.S. export controls will restrict China’s access to advanced chip manufacturing technology for the next decade, significantly curtailing its capacity to dominate the high-end AI chip arena. This reality positions the U.S. as a key player and creates a substantial opportunity for its closest ally, the UK, which excels in chip design.

The UK has already birthed several companies in this sector, such as Fractile, Flux, and Oriole. However, we lack the necessary scale to capitalize on the opportunity. Instead of competing with Nvidia in data center computing, we should focus on specialized applications that usher in innovation, like robotics, factory automation, medical devices, and autonomous vehicles.

These domains offer ample opportunities for inventive architectures and new competition.

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Too frequently, Britain’s industrial strategy is impeded by national insecurity and a lack of confidence. This must change. Primarily, governments must advocate decisively for our intent to excel in AI chips.

Secondly, we should aim to double our chip design workforce from the current 12,000 within a decade and encourage more talented individuals to pursue electrical engineering and computer science through generous scholarships. A target of 1,500 new students each year is achievable. Universities must offer relevant courses, and governments need to enhance financial support.

Thirdly, the UK should fully utilize its investment instruments: the Sovereign AI Fund, the British Business Bank, the National Wealth Fund, and the Ministry of Defence’s initiatives to ‘buy British’.

Fourthly, the UK-US strategic partnership must serve as a foundation for greater collaboration with leading US chip manufacturers and facilitate access to their state-of-the-art sub-3 nanometer manufacturing technologies. Collaborating with our U.S. partners to develop a robust supply chain and innovation pipeline is essential.

If the UK commits fully, the emerging age of AI could be characterized not only by code but also by silicon, leaving a distinctly British legacy.

Source: www.theguardian.com

Astronomers Capture Direct Images of Brown Dwarfs Orbiting Nearby Red Dwarfs

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Astronomers utilized the Subaru Telescope, W.M. Keck Observatory, and ESA’s Gaia mission to capture images of the brown dwarf companion orbiting the M dwarf star LSPM J1446+4633.

NIRC2 image of J1446 taken in August 2023. The white arrow indicates the location of the new companion J1446B. Image provided by: Uyama et al., doi: 10.3847/1538-3881/ae08b6.

LSPM J1446+4633 (J1446) is a nearby mid-M dwarf, situated 17 parsecs (55 light-years) away.

The newly identified brown dwarf orbits its parent star at a distance approximately 4.3 times that of the Earth from the sun, completing an orbit every 20 years.

This object, designated J1446B, has a mass ranging from 20 to 60 times that of Jupiter.

“The success of this discovery was due to the combination of three complementary observational methods: (i) radial velocity (RV) measurements via long-term infrared spectroscopic monitoring by Subaru’s IRD instrument, (ii) high-resolution near-infrared imaging with advanced adaptive optics at the W.M. Keck Observatory, and (iii) precise astronomical acceleration measurements from ESA’s Gaia mission,” stated California State University astronomer Taichi Uyama and his team.

“By integrating these datasets and applying Kepler’s laws, we were able to determine the dynamic mass and orbital parameters of J1446B with unprecedented precision.”

“Radial velocity data by itself cannot differentiate between mass and orbital inclination, but the addition of direct imaging and Gaia data resolves this ambiguity.”

“The Subaru IRD-SSP program provided crucial RV data, while Keck’s cutting-edge adaptive optics allowed for the direct detection of the companion star at very close distances from the host star.”

“Previous studies have shown that astronomical acceleration from Hipparcos and Gaia can be combined with direct imaging to detect and analyze companion objects.”

“However, Hipparcos was unable to measure faint red dwarf stars like J1446.”

“Our study is the first to apply Gaia-only acceleration data to such a system, successfully constraining the orbit and dynamical mass of a brown dwarf companion.”

Near-infrared observations of J1446B indicated a brightness variation of about 30%, hinting at dynamic atmospheric phenomena such as clouds or storms.

“This finding serves as a significant benchmark for testing brown dwarf formation theories and atmospheric models,” the astronomers noted.

“Future spectroscopic studies may enable researchers to map the weather patterns on this intriguing object.”

“This achievement highlights the efficacy of combining ground-based and space-based observatories in discovering hidden worlds beyond our solar system.”

The team’s paper was published in Astronomy Magazine.

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Taichi Uyama et al. 2025. Direct Image Exploration for Companions with Subaru/IRD Strategic Program II. A brown dwarf companion star was discovered around the nearby medium-M dwarf LSPM J1446+4633. A.J. 170, 272; doi: 10.3847/1538-3881/ae08b6

Source: www.sci.news

Webb Discovers Biosignature Gas Phosphine in the Atmospheres of Ancient Brown Dwarfs

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Astronomers utilizing the NASA/ESA/CSA James Webb Space Telescope have identified phosphine (PH)3 in the atmosphere of the brown dwarf Wolf 1130c, part of the triple system 1130ABC.

Schematic diagram of the Wolf 1130ABC triple system, featuring red dwarf star Wolf 1130a (left), compact white dwarf companion 1130b (center), and distant brown dwarf Wolf 1130c (right); each component scaled according to its relative size. Image credit: Adam Burgasser.

Wolf 1130ABC is located approximately 54 light years away in the constellation Cygnus.

The system is also known for LHS 482, Gliese 781, and Ross 1069b. It consists of three components: the Cool Red Star Wolf 1130a, the massive white dwarf Wolf 1130b, and the brown dwarf Wolf 1130c.

Initially discovered in 2013, Wolf 1130c orbits the closely bound systems of Wolf 1130a and Wolf 1130b on a wide trajectory.

“The astronomical initiative known as the Ancient Arcana concentrates on ancient, metal-rich brown dwarfs to enhance our understanding of atmospheric chemistry,” stated Adam Burgasser, a professor at the University of California, San Diego.

“Identifying phosphine was one of our primary objectives.”

Phosphine naturally emerges in the hydrogen-dominated atmospheres of gas giants like Jupiter and Saturn.

This has led scientists to theorize that phosphine should exist in the atmospheres of exoplanetary gas giants as well.

Nevertheless, previous Webb observations often failed to detect phosphines, pointing to an incomplete understanding of phosphorus chemistry.

“Before Webb, the expectation was that phosphine would be plentiful in planetary and brown dwarf atmospheres, according to theoretical models based on the turbulent mixing in these environments.”

Wolf 1130c is of particular interest to brown dwarf astronomers due to its lower concentration of “metals” (elements beyond hydrogen and helium) compared to the Sun.

In contrast to other brown dwarfs, the team successfully detected phosphines in the infrared spectral data collected by Webb from Wolf 1130c.

To accurately interpret their findings, researchers needed to ascertain the abundance of this gas within the atmosphere of Wolf 1130c.

“We employed a modeling approach called atmospheric recovery to quantify the molecular constituents of Wolf 1130c,” explained Dr. Irene Gonzalez from San Francisco State University.

“This technique leverages Webb’s data to validate the expected presence of various molecular gas species in the atmosphere.”

“It’s akin to reverse-engineering a delicious cookie when a chef remains committed to a recipe.”

“Typically, phosphorus may bond with other molecules, such as phosphorus trioxide,” remarked Dr. Baylor.

“In the metal-poor atmosphere of Wolf 1130c, insufficient oxygen prevents phosphorus from forming this way, allowing it to arise from phosphine-rich hydrogen.”

Alternatively, the phosphine could have been synthesized locally within the Wolf 1130ABC system, particularly from the white dwarf Wolf 1130b.

“The white dwarf represents the remnant shell of a star that has completed hydrogen fusion,” Professor Burgasser explained.

“These stars are incredibly dense and can accumulate material on their surfaces, potentially spurring runaway nuclear reactions.”

While astronomers have not observed such phenomena in the Wolf 1130ABC system in recent history, nova events usually cycle every thousands to tens of thousands of years.

This system has been recognized for just a century, and earlier invisible explosions may have contributed to a legacy of phosphorus contamination.

Gaining insights into why this particular brown dwarf exhibits a distinct signature of phosphine could shed new light on phosphorus synthesis in the Milky Way and atmospheric chemistry on exoplanets.

“If we aim to use this molecule in the quest for life in terrestrial worlds outside our solar system, understanding the atmospheric phosphine chemistry of brown dwarfs becomes crucial,” Professor Burgasser commented.

This study will be published in the journal Science.

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Adam J. Burgasser et al. Observation of unexpected phosphines in the atmosphere of the cold brown dwarf. Science. Released online on October 2, 2025. doi:10.1126/science.adu0401

Source: www.sci.news

Webb Discovers Auroras Using Free-Floating Brown Dwarfs

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Astronomers utilizing the NASA/ESA/CSA James Webb Space Telescope have found evidence of energy deposition in the upper atmosphere of the nearby brown dwarf SIMP J013656.5+093347.3 caused by auroras.

Artist’s impression of aurora and brown dwarf SIMP-0136. Image credit: Evert Nasedkin.

SIMP J013656.5+093347.3 (commonly referred to as SIMP-0136) is a low-mass brown dwarf located 20 light years away in the Pisces constellation, approximately 6.12 light years from Earth.

As part of the Carina-near Stellar Association, this celestial object is estimated to be around 200 million years old.

The mass of SIMP-0136 is roughly estimated to fall between 12.7 and 17.8 times that of Jupiter.

With a spectral type of T2.5 and a temperature nearing 1,100 K, it exhibits many atmospheric properties similar to those of directly imaged exoplanets, such as HR 8799B and AF Lep b.

“Our observations have illuminated the activity of the robust aurora of SIMP-0136, which warms its atmosphere, much like the auroras on Earth and the powerful auroras found on Jupiter.”

“These measurements represent some of the most precise assessments of the atmospheres of extreme objects to this date, with direct measurements of atmospheric changes occurring for the first time.”

“Furthermore, with temperatures exceeding 1,500 degrees Celsius, SIMP-0136 will display mild heat waves this summer.”

“Our specific observations indicated that we could precisely record temperature variations of less than 5 degrees Celsius.”

“These temperature fluctuations were linked to minor alterations in the chemical makeup of this free-floating planet, hinting at storms akin to the Great Red Spot on Jupiter.

Another unexpected finding was the constancy of cloud variability in SIMP-0136.

Changes in cloud coverage might typically lead to atmospheric changes, similar to the variability observed with patches of clouds and clear skies on Earth.

However, astronomers discovered that cloud coverage remains stable across the surface of SIMP-0136.

At SIMP-0136’s temperatures, these clouds are distinct from Earth’s, primarily composed of silicate grains reminiscent of beach sand.

“Different wavelengths of light are associated with various atmospheric features,” stated Dr. Nasedkin.

“Similar to observing color changes on Earth’s surface, the color variations of SIMP-0136 are driven by alterations in atmospheric properties.”

“Utilizing advanced models enables us to deduce atmospheric temperature, chemical composition, and cloud positioning.”

“This work is thrilling as it showcases that by leveraging cutting-edge modeling techniques on Webb’s advanced datasets, we can understand the processes driving global weather throughout our solar system.”

“Understanding these meteorological processes is crucial as we continue discovering and characterizing exoplanets in the future.”

“Currently, such spectroscopic variability observations are limited to isolated brown dwarfs, but large telescopes and future studies, along with the eventual establishment of a habitable world observatory, will allow us to explore the atmospheric dynamics of exoplanets ranging from gas giants like Jupiter to rocky planets.”

The team’s survey results will be published in the journal Astronomy and Astrophysics.

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E. Nasedkin et al. 2025. JWST Weather Report: Investigating temperature variations, aurora heating, and stable cloud coverage on SIMP-0136. A&A 702, A1; doi: 10.1051/0004-6361/202555370

Source: www.sci.news

Astronomers Discover Rare Cloud-Forming Chemicals in Ancient Brown Dwarfs Dating Back a Billion Years

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Utilizing data gathered by NSF’s Gemini South Telescope and NASA/ESA/CSA James Webb Space Telescope, astronomers have identified methane signatures (CH4), water (H2O), and silane (SiH4) in the cold brown dwarf gas WISEA J153429.75-104303.3 (shortened to W1534). Silanes are predicted to act as significant reservoirs of silicon, the element responsible for the large clouds of gas that surround giant worlds, but their presence had remained undetected until now, masked by the development of deep silicate clouds in the observable atmosphere.

This artist’s illustration depicts a brown dwarf with an atmosphere filled with gas and dust clouds. Image credits: Noirlab/NSF/Aura/R. Proctor.

The W1534, referred to as the accident, is situated approximately 50 light years from Earth in the Libra constellation.

This brown dwarf was likely formed between 100 and 120 billion years ago and ranks among the oldest brown dwarfs discovered to date.

First identified in 2020 by citizen scientists participating in the Backyard Worlds: Planet 9 Citizen Science Project, its unusual light profile captivated astronomers.

Using two of the world’s most advanced terrestrial and space-based telescopes, astronomers examined its atmosphere to analyze its properties and composition.

The survey commenced with NSF’s Noirlab Astronomer Sandy Leggett capturing near-infrared images of W1534 with a Gemini South telescope in Chile, part of the International Gemini Observatory.

This initial work laid the groundwork for further explorations using Webb, guided by Noirlab Astronomer Aaron Meisner.

“W1534 is quite faint, and Gemini South is the only ground-based telescope capable of detecting it,” Dr. Meisner stated.

“The Gemini discovery paved the way for Webb’s observations by revealing the deeper atmospheric layers of this mysterious object and enabling us to determine the exposure time necessary to gather useful near-infrared data on its composition.”

Within W1534’s atmosphere, the team uncovered the crucial signature of silane, a compound formed from silicon and four hydrogen atoms.

Planetary scientists have long theorized the existence of this molecule within gas giants, attributing potential significance to its role in cloud formation within the atmosphere.

Despite extensive searches, its atmospheric presence has remained elusive in our solar system’s gas giants, Jupiter and Saturn, although thousands of studies on brown dwarfs and gas giants orbiting other stars have occurred.

This marks the first discovery of silanes in any brown dwarf, exoplanet, or solar system object.

The absence of this molecule in all but one singular brown dwarf suggests intriguing insights into the chemistry occurring in such an ancient environment.

“Often, it is these extreme objects that help us understand the average,” remarked Dr. Jackie Faherty, a researcher at the American Museum of Natural History.

The presence of silanes in W1534’s atmosphere implies that in very ancient objects, silicon is capable of bonding with hydrogen to form lighter molecules that can ascend to the upper layers of a gas giant’s atmosphere.

In contrast, more recently formed objects, such as Jupiter and Saturn, result in silicon bonding with readily available oxygen, producing heavier molecules that settle deeper into the atmospheric layers.

The evidence gleaned from W1534’s atmosphere further validates astronomers’ comprehension of gas giant cloud formation and sheds light on how primitive conditions influence atmospheric composition.

Moreover, it indicates that worlds formed billions of years ago display characteristics distinctly different from those formed during the early solar system.

“The formation and detection of silanes highlight an essential relationship among composition, cloud formation, and atmospheric mingling in cold brown dwarfs and planetary atmospheres,” the authors concluded.

Their paper is published in the journal Nature.

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jk faherty et al. 2025. A silicate precursor silane detected in cold, low-metallic brown dwarfs. Nature 645, 62-66; doi:10.1038/s41586-025-09369-1

Source: www.sci.news

Astronomers Uncover Polar Ejection Stripping Systems Surrounding Brown Dwarf Pairs

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The recently identified planet orbits a binary system comprising two equal brown dwarf stars positioned at a 90-degree angle from 2mass J15104786-2818174 (hereafter referred to as 2M1510).

This diagram illustrates exoplanets orbiting two brown dwarfs. Image credit: ESO/M. Kornmesser.

Cardiovascular planets represent the realm of diabetes found within a binary star system.

These planets generally have orbits aligned with the planes in which their host stars revolve around one another.

Previously, there were indications that planets might exist in vertical or polar orbits. Theoretically, these orbits were stable, and disc formations observed suggested potential planets around polar orbits of stars.

However, astronomers have now obtained clear evidence of the existence of these polar planets.

“We are thrilled to have played a role in finding robust evidence for this configuration,” stated PhD candidate Thomas Beycroft from the University of Birmingham.

The newly discovered exoplanet, 2M1510B, orbits a unique pair of young brown dwarfs.

These brown dwarfs undergo mutual solar eclipses as viewed from Earth, a characteristic that qualifies them within what astronomers refer to as a binary system.

This configuration is exceptionally rare, marking only the second identified pair of brown dwarfs and the first solar system discovered at a right angle relative to the orbit of its two host stars.

Artist’s impression of the unusual trajectory of 2M1510B around the brown dwarf. Image credit: ESO/L. Calsada.

“The planet revolving around the binary brown dwarfs in a polar orbit is remarkably thrilling,” commented Amalie Triaudo, a professor at the University of Birmingham.

Astronomers discovered 2M1510B by refining the trajectories and physical characteristics of the two brown dwarfs using UV and Visual Echelle Spectroscopy (UVES) at ESO’s Very Large Telescope.

The researchers observed strange forces acting on the trajectory of the brown dwarf, leading to speculation about a unique formation with an unusual orbital angle.

“After considering all plausible scenarios, the only explanation consistent with our data is that the planet within this binary is in polar orbit,” Beycroft noted.

“This discovery was fortuitous, as our observations weren’t initially aimed at studying the composition or orbit of such a planet, making it an exciting surprise,” Professor Triaud explained.

“Overall, I believe this not only showcases our astronomers’ capabilities but also illuminates the possibilities within the intriguing universe we inhabit.”

This image depicts the triple system 2M1510. Image credits: Centre Donna Astromyk destrasbourg/Sinbad/Panstars.

This discovery was made possible due to innovative data analysis developed by Dr. Larita Sylum of Cambridge University.

“We can derive their physical and orbital parameters from the variation in speed between the two brown dwarfs, although these measurements were previously uncertain,” Dr. Sairam remarked.

“This improvement has revealed that the interactions between the two brown dwarfs are intricately influenced.”

Study published in the journal Advances in Science.

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Thomas A. Baicroft et al. 2025. Evidence of polar drainage bulges orbiting a pair of brown dwarfs. Advances in Science 11 (16); doi:10.1126/sciadv.adu0627

Source: www.sci.news

Strange vertical orbits of an exoplanet observed around a binary brown dwarf system

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Impression of the artist in the unusual orbit around the brown dwarf of ExoPlanet 2M1510 (AB)B

ESO/L. Calsada

It was first revealed that a pair of rare stars have equally rare companions, exoplanets that rush into orbit vertically.

Astronomers may think they know what the normal thing is about stars and planets, but they say, “But the universe is very diverse.” Amaury Triaud At the University of Birmingham, UK. He and his colleagues unexpectedly discovered evidence of rare constructs while analyzing data collected by a very large Chilean telescope.

The two stars are brown d stars. This means that they are small and very dim because they cannot maintain fusion and are often referred to as failed stars or subseber ral objects. They follow orbit and continue to cover each other when viewed from Earth. Researchers have previously observed only one brown d-star binary.

Triaud and his colleagues carefully analyzed the new binary system to determine the mass of the stars and their movements, and unexpectedly strange signals were found in the data. Ultimately, the only physical scenario that can explain it is that of a planet-sized object orbiting two stars, following an ellipse perpendicular to the star’s orbit.

Triaud says that vertical orbit is not entirely unheard of, but he and his colleagues never expected to see it in this context. “Brown dwarfs are rare. Brown dwarf pairs are rare. Covering a pair of brown dwarfs is even more unusual and faint, making it difficult to measure,” he says. “That was a surprise. In a system that is ideal and not rare in itself, there is this configuration.”

Twenty years ago, such a structure was considered science fiction, but now it has become a scientific fact. Katherine Brandel At Oxford University. “This is a truly beautiful outcome,” she says. Details of the impending orbit of the two stars make a strong claim that this “harmonograph of the sky” is authentic. By studying how they eat each other, we can identify more details about this unique trio’s moves going forward, Blundell says.

Researchers would like to learn more about the exoplanet named 2M1510(AB)B, but can be compared to a fictional tattoo. Star Warsa desert world orbiting two suns. However, the two suns on the 2M1510(AB)B dimming and get exposed to the surface with something similar to the double dose of moonlight.

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Source: www.newscientist.com

New research suggests early mammals possessed dark, dim greyish brown fur

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Fur colours, which serve many functions, are essential for the evolution of mammal behavior, physiology and habitat preferences. However, little is known about the colour of Mesozoic mammals that co-evolved with dinosaurs. In a new study, scientists from China, Belgium, the Netherlands, the UK and the US used the dataset Melanosome (Melanin-Containing Organelle) We quantitatively measured the morphology and quantitatively measured hair colours of 116 live mammals to reconstruct the colours of six Mesozoic mammals, including the species Yuhalamiidan mammals that were not previously described.

Reconstructing the life of Shenshou Luian extinct squirrel-like euhalamidian species from the Jurassic region of central China. Image credit: Tamuranobu, http://spinops.blogspot.com.

From communication to camouflage, animal colour plays an important role in many behavioral ecological functions.

Some animals exhibit distinct and vivid arrangements like birds, but mammalian fur is generally limited to muted tones due to their dependence on the single pigment melanin.

Mammals lack palettes, but have evolved a diverse and distinctive coat pattern.

However, due to lack of data on pigmentation in extinct mammals, the evolutionary history of hairy colour is not well understood.

Recent studies have shown that melanosomes, which cause pigmentation, can be preserved in fossilized specimens.

A similar technique has successfully reconstructed the colours of dinosaurs, but despite well-preserved fur specimens, it has not been widely applied to fossil mammals.

In the new study, Dr. Ruoshuang Li, a colleague of the Chinese University of Earth Sciences and colleague, analyzed melanosomes in 116 living mammals and created a predictive model to reconstruct the hairy colour based on melanosome morphology.

The authors applied the model to six Mesozoic mammalian forms of fossilized melanosomes, including the newly described euhalamyidan species that lived 158.5 million years ago (Late Jurassic Epoch).

The authors found that the fur of these early mammals was primarily and uniformly dark in colour, with no stripes and spots that adorn many modern mammals.

This suggests that despite evolutionary differences in phylogenetics and ecology, the early mammalian melanin colored systems remained little different.

This is in stark contrast to the diverse melanosome structures found in feathered dinosaurs, early birds and pterosaurs, indicating a distinct evolutionary pattern of mammalian colour.

“The typical modern nocturne mammals, such as the dark, uniformly dull fur found in these species – moles, mice, rats and nocturne bats, support the previous hypothesis that early mammals are also largely nocturne and colored for camouflage,” the researchers said.

“In addition, the high melanin content of the fur may have been beneficial in providing mechanical strength for thermoregulation and protection.”

“Following the Cretaceous – Fat extinction event, mammals rapidly diversified into niches previously occupied by dinosaurs, leading to more diverse melanosome structures and new perage colour strategies that are more suited to a more diverse environment.”

Survey results It was published in the journal today Science.

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rushuang li et al. 2025. Mesozoic mammalian forms illuminate the origin of the colour of the hair. Science 387 (6739): 1193-1198; doi: 10.1126/science.ads9734

Source: www.sci.news

Webb’s study highlights brown dwarfs in the fire nebula

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Astronomers using the NASA/ESA/CSA James Webb Space Telescope investigated the lowest mass limits of brown dwarfs within Flame Nebula, a hotbed of star formation in Orion’s constellation.

A collage of this image from the Flame Nebula shows a view of near-infrared light from Hubble on the left, while the two insets on the right show the near-infrared view taken by Webb. Image credits: NASA/ESA/CSA/M. Meyer, University of Michigan/A. Pagan, Stsci.

Flame Nebula It is about 1,400 light years away from Orion’s constellation.

Also known as NGC 2024 and SH2-277, this ejection nebula is about 12 light years wide and is less than a million years.

The Flame Nebula was discovered on January 1, 1786 by British astronomer William Herschel, born in Germany.

It is part of the Orion molecular cloud complex and includes famous nebulae such as the Hosehead Nebula and the Orion Nebula.

In a new study, astronomers used Webb to explore the lowest mass limits of brown dwarfs within the flame nebula.

The results, they found, were free-floating objects with mass about 2-3 times the mass of Jupiter.

“The goal of this project was to explore the fundamental low-mass limits of the star- and brown dwarf formation process,” said Dr. Matthew De Julio, an astronomer at the University of Texas at Austin.

“Webb allows you to investigate the faintest and lowest mass objects.”

The low mass limits that the required teams are looking for are set by a process known as fragmentation.

In this process, the large molecular clouds that produce both star and brown dwarfs are broken down into smaller units or fragments.

Fragmentation relies heavily on several factors where temperature, thermo-pressure, and gravity balance are the most important.

More specifically, as fragments contract under gravity, their cores become hot.

If the core is large enough, the hydrogen starts to fuse.

The outward pressure created by that fusion counters gravity, stops collapse and stabilizes the object.

However, the core is not compact, it is hot enough to burn hydrogen, and continues to shrink as long as it emits internal heat.

This near-infrared image of a portion of the Webb flame nebula highlights three low-mass objects found in the right inset. Image credits: NASA/ESA/CSA/STSCI/M. MEYER, University of Michigan.

“We’ve seen a lot of effort into making it,” said Dr. Michael Meyer, an astronomer at the University of Michigan.

“If the clouds cool efficiently, they collapse and fall apart.”

When the fragment becomes opaque enough to reabsorb its own radiation, fragmentation stops, thereby stopping cooling and preventing further decay.

The theory places the lower bounds of these fragments between 1-10 Jupiter masses.

This study significantly reduces its scope as the Webb census counted fragments of different masses within the nebulae.

“As we found in many previous studies, going to a lower mass actually increases the amount of objects about ten times as much as Jupiter’s mass,” Dr. Deirio said.

“Studies using Webb are sensitive to Jupiter up to 0.5 times the mass of Jupiter, and as they get below 10 times the mass of Jupiter, there are considerably fewer.”

“We discovered that there are fewer 5 Jupiter Mass objects than the Ten Jupiter Mass object, and we can see that there are fewer 3 Jupiter Mass objects than the 5 Jupiter Mass objects.”

“We don’t actually find any objects below the mass of two or three Jupiter. We’re hoping to see if they’re there, so we’re assuming this could be the limit itself.”

“For the first time, Webb was able to investigate beyond that limit,” added Dr. Meyer.

“If that limitation is real, there really is no object of 1 Jupiter mass that floats freely in our Milky Way galaxies, unless it forms as a planet and is kicked out of the planetary system.”

a paper Regarding the survey results, Astrophysics Journal Letter.

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Matthew de Julio et al. 2025. Identification of sales in the initial mass function of young star clusters up to 0.5 mJ. apjl 981, L34; doi: 10.3847/2041-8213/ADB96A

Source: www.sci.news

Webb’s discovery of brown dwarf candidates hints at first wealthy population outside of the Milky Way

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Astronomers using the NASA/ESA/CSA James Webb Space Telescope detected a population of 64 brown dwarf candidates with masses ranging from 50 to 84 Jupiter masses in the star cluster NGC 602.

This image of NGC 602 includes data from Webb's NIRCam (near-infrared camera) and MIRI (mid-infrared instrument) instruments. Image credits: NASA / ESA / CSA / Webb / P. Zeidler / E. Sabbi / A. Nota / M. Zamani, ESA & Webb.

NGC602 is a very young star cluster, about 200,000 light-years away in the constellation Hydra, about 2 to 3 million years old.

Also known as ESO 29-43, this star resides in the wings of the Small Magellanic Cloud.

NGC 602's local environment closely resembles that of the early Universe, with very low abundances of elements heavier than hydrogen and helium.

The presence of dark clouds of dense dust and the fact that the cluster is rich in ionized gas also suggests the presence of an ongoing star formation process.

Together with the associated HII region N90, which contains clouds of ionized atomic hydrogen, this cluster provides a rare opportunity to examine star formation scenarios under conditions dramatically different from those in the solar neighborhood.

Using Webb, Dr. Peter Zeidler and his colleagues at AURA and ESA were able to detect 64 brown dwarf candidates in NGC 602. This is the first rich population of brown dwarfs to exist outside the Milky Way.

“It is possible to detect objects at such great distances only with incredible sensitivity and spatial resolution in the right wavelength range,” Dr. Zeidler said.

“This has never been possible and will remain impossible from the ground for the foreseeable future.”

“So far, about 3,000 brown dwarfs are known, and they all live in our galaxy,” said Dr. Elena Mangiavakas, also from AURA and ESA.

“This discovery highlights the ability to use both Hubble and Webb to study young star clusters,” said Dr. Antonella Nota, executive director of the International Space Science Institute.

“Hubble showed that NGC 602 hosts very young, low-mass stars, but only Webb can conclusively confirm the extent and significance of substellar mass formation in this cluster. Hubble and Webb are an amazingly powerful telescope duo!”

“Our results are very consistent with the theory that the mass distribution of objects below the hydrogen burning limit is simply a continuation of the stellar distribution,” Dr. Zeidler said.

“They seem to form the same way, they just haven't accumulated enough mass to become full stars.”

NSF astronomer Dr. Elena Sabbi said, “Studying the newly discovered metal-poor young brown dwarfs in NGC 602 will shed light on how stars and planets formed under the harsh conditions in the early universe. We are getting closer to uncovering the secrets of this.” NOIRLab, University of Arizona, Space Telescope Science Institute.

“These are the first substellar objects outside the Milky Way,” Manjavakas said.

“We need to be prepared for new breakthrough discoveries in these new objects.”

of result will appear in astrophysical journal.

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peter zeidler others. 2024. A candidate for a subsolar metallic brown dwarf is discovered in the Small Magellanic Cloud. APJ 975, 18; doi: 10.3847/1538-4357/ad779e

Source: www.sci.news

Understanding the Strange Nature of the First Discovered Brown Dwarf

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Congratulations, you're twins

K. Miller, R. Hart/California Institute of Technology/IPAC

A strange star that has confused researchers for decades now makes sense. It turns out that it is not a single star, but two companion stars.

“Previously, it was thought that this brown dwarf was meaningless. We wondered if we were doing something horribly wrong, or if our models were horribly wrong. I was worried. But no, everything is fine. I just have friends.” timothy blunt at the Space Telescope Science Institute in Maryland.

Now, two research teams have used instruments from the W.M. Keck Observatory in Hawaii and the Very Large Telescope in Chile to solve the mystery of the first brown dwarf.

Brown dwarfs are “failed stars” in that they have too little material and are too hot to sustain nuclear fusion. Instead of shining brightly for thousands of years, they dim in the night sky like planets. The first brown dwarf, called Gliese 229B, was discovered in 1995 and had an inexplicably large mass. Jerry Xuan I worked on one of the studies at the California Institute of Technology.

Gliese 229B is estimated to have about 71 times the mass of Jupiter, and a star born at that size, even if it were as old as the universe, would cool down and become faint enough to see us. That would have never happened, said participant Brandt. One of the research team. This has led some researchers to suggest that Gliese 22B is a very faint pair of stars, but until now there has been no conclusive evidence.

Xuan said this was because two fellow brown dwarfs, Gliese 229Ba and Bb, were unusually close together, and very precise observations were needed to see them both. However, observations by both teams confirmed that they exist separately, orbiting each other every 12 days, and are always about 16 times the distance between Earth and the Moon.

He says that revealing the dual identity of Gliese 229B may be the start of a trend. samuel white book He was part of a research team at the California Institute of Technology. “There are probably a lot of binary systems that have been hiding in front of us all this time,” he says.

Xuan said he has already selected several other brown dwarfs to study more precisely. Brown dwarfs resemble both exoplanets and stars, so understanding how many of them are actually twins could shed light on the formation of these other objects as well. Maybe.

topic:

Source: www.newscientist.com

Cool brown dwarf emits methane detected by Webb

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Astronomers using the NASA/ESA/CSA James Webb Space Telescope detected methane emissions from the. CWISEP J193518.59-154620.3 (W1935 for short) is an isolated brown dwarf star with a temperature of about 482 K. Their findings also suggest that W1935 could produce auroras similar to those seen on our planet, Jupiter, and Saturn.

Artist's impression of the brown dwarf W1935. Image credit: NASA/ESA/CSA/L. Hustak, STScI.

W1935 is located about 47 light-years away in the constellation Sagittarius.

This brown dwarf was co-discovered by Backyard Worlds: Planet 9 citizen science volunteer Dan Caselden and NASA's CatWISE team.

W1935's mass is not well known, but it is probably in the range of 6 to 35 times the mass of Jupiter.

After observing numerous brown dwarfs observed by Webb, Dr. Jackie Faherty Researchers at the American Museum of Natural History found W1935 to be similar, with one notable exception. It was emitting methane, which had never been seen before in brown dwarfs.

“Methane gas is expected to be present in giant planets and brown dwarfs, but we typically see it absorbing light rather than absorbing it,” Faherty said.

“At first we were confused by what we were seeing, but eventually it turned into pure excitement when it was discovered.”

Computer modeling provided another surprise. W1935 may have a temperature inversion, a phenomenon in which the atmosphere becomes warmer as altitude increases.

Temperature inversions easily occur in planets orbiting stars, but brown dwarfs are isolated and have no obvious external heat source.

“We were pleasantly shocked when the model clearly predicted a temperature inversion,” said Dr Ben Burningham, an astronomer at the University of Hertfordshire.

“But we also needed to figure out where that extra upper atmosphere heat was coming from.”

To find out, astronomers turned to our solar system. In particular, they focused on the study of Jupiter and Saturn. Both show methane release and temperature inversions.

Since the aurora is likely the cause of this feature on the solar system's giants, the researchers speculated that they had discovered the same phenomenon in W1935.

Planetary scientists know that one of the main drivers of Jupiter and Saturn's auroras are high-energy particles from the sun that interact with the planets' magnetic fields and atmospheres, heating the upper layers.

This is also the reason for the aurora borealis we see on Earth. Auroras are most unusual near the poles, so they are commonly referred to as aurora borealis or southern lights.

However, W1935 does not have a host star, so solar wind cannot contribute to the explanation.

There's another fascinating reason why auroras occur in our solar system.

Both Jupiter and Saturn have active moons that occasionally eject material into space, interacting with the planets and enhancing the auroral footprints of those worlds.

Jupiter's moon Io is the most volcanically active world in the solar system, spewing fountains of lava tens of miles high. Also, Saturn's moon Encereadus spews water vapor from geysers that freeze and boil as soon as they reach space.

Although more observations are needed, researchers speculate that one explanation for W1935's aurora may be an active moon that has yet to be discovered.

“Every time astronomers point an object at the Webb, new and surprising discoveries can occur,” Dr. Faherty said.

“When we started this project, we weren't concerned about methane emissions, but now that we know that methane emissions can exist and the explanations are very attractive, we're always paying attention. That's part of how science moves forward.”

a paper The survey results were published in a magazine Nature.

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JK Faherty other. 2024. Methane emission from cool brown dwarfs. Nature 628, 511-514; doi: 10.1038/s41586-024-07190-w

Source: www.sci.news

Researchers solve the enigma of the brown giant panda

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The brown and white giant panda is a mutant with a unique coat color found only in the world. Qinling Mountains Chinese.

Kizai is the only brown panda living in captivity. Image credit: Ailie HM / CC BY-SA 4.0 Certificate.

“Variation in fur color has considerable adaptive and cultural value in mammals,” said study lead author Dengfeng Guan, Ph.D., from the Key Laboratory of Animal Ecology and Conservation Biology, Chinese Academy of Sciences, and colleagues.

“This property is directly determined by the ratio of eumelanin to pheomelanin and the density and distribution of melanosomes within the hair.”

“These factors are under complex control by hundreds of genes that influence different aspects of melanogenesis, including melanocyte proliferation and migration, melanin synthesis, and melanosome biogenesis and translocation.”

Giant panda (Airuropoda melanoruca) is one of the most charismatic flagship breeds, distinguished by its striking black and white coat.

However, the discovery brown panda (Ailuropoda melanoleuca qinlingensis) This photograph, taken in the Qinling Mountains of China's Shaanxi province, challenges the conventional wisdom that color photographs of pandas are never possible.

Recognized as a subspecies of the giant panda, this brown panda is extremely rare and is definitely designated as a national treasure.

Since the first brown panda was discovered in 1985, 11 records have been reported by official news or private communications, seven of which have been confirmed by photographs or physical objects. Three cases were from Buping County, two from Yang County, one from Taibai County, and one from Taibai County. Zhou Zhi.

All brown pandas are found only in the Qinling Mountains, indicating that they are endemic to this region.

“The first recorded brown panda, a female named Dan Dan, was rescued from Foping Nature Reserve to Xi'an Zoo in 1985,” the biologists explained.

“She then mated with the black panda Wang Wang and gave birth to a male black panda named Qing Qing in captivity.”

“Dan Dan passed away in 2000 and Chin Chin also died in 2006, leaving no descendants.”

“In 2009, Qi Zhai, a male brown panda cub, was rescued from Fo Ping Nature Reserve and is currently the only brown panda living in captivity.”

Dr. Guan and co-authors established two family trios related to the brown panda Qi Zai and sequenced their genomes.

They analyzed ecological and genetic data obtained from a long-term study of wild giant pandas in Fo Ping Nature Reserve.

Additionally, we investigated the cellular mechanisms underlying brown fur color based on microscopy and transmission electron microscopy analyses.

They are candidate mutations, viz. base 2 The gene is thought to be the most likely genetic basis for brown pandas.

They verified this deletion through sequencing an additional cohort of 192 black pandas and CRISPR-Cas9 knockout mice.

Their findings will not only provide insight into the genetic basis of coat color variation in brown pandas and wild animals, but will also guide the scientific breeding of rare brown pandas.

“The extremely small number of brown pandas and the nature of the frameshift deletion mutation suggest that this mutation may be a neutral or weakly deleterious mutation,” the authors said.

“Remarkably, the two brown pandas (Qi Zai and Dan Dan) are showing normal growth and reproduction; base 2 The knockout mice were viable, fertile, and had no obvious physical abnormalities, indicating that this mutation had no apparent negative impact on the physical fitness of these mice. ”

“However, other physiological effects of this mutation on brown pandas remain unclear. base 2 It is known to be involved in the Alzheimer's disease pathway. ”

“Given the small population size of Qinling giant pandas, weak deleterious mutations may be corrected by genetic drift effects.”

“Further studies on brown pandas and knockout mouse models will therefore provide valuable insight into the functional consequences of this mutation.”

“For a rare coat color mutant of the giant panda that has great scientific and ornamental value, our findings will provide guidance for the scientific breeding of brown pandas.”

of study Published online this week Proceedings of the National Academy of Sciences.

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Dengfeng Guan other. 2024. Color photography: homozygous 25 bp deletion base 2 Giant pandas can have brown and white coats. PNAS 121 (11): e2317430121; doi: 10.1073/pnas.2317430121

Source: www.sci.news

Webb observes auroras on cold brown dwarf star

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Using NASA/ESA/CSA’s James Webb Space Telescope, astronomers detected a brown dwarf with infrared emissions from methane, likely due to energy in the upper atmosphere. The heating of the upper atmosphere that drives this emission is associated with auroras. The brown dwarf, named W1935, is located 47 light-years away.

Artist’s impression of the brown dwarf W1935. Image credit: NASA/ESA/CSA/L. Hustak, STScI.

On Earth, auroras occur when energetic particles blasted into space from the sun are captured by Earth’s magnetic field.

They cascade into the atmosphere along magnetic field lines near the Earth’s poles, colliding with gas molecules and creating eerie, dancing curtains of light.

Jupiter and Saturn have similar auroral processes that involve interaction with the solar wind, but also receive auroral contributions from nearby active moons, such as Io (for Jupiter) and Enceladus (for Saturn). Masu.

“For an isolated brown dwarf like W1935, the absence of a stellar wind that contributes to auroral processes and accounts for the extra energy in the upper atmosphere required for methane emission is puzzling,” American Airlines astronomers said. said Dr. Jackie Faherty. Natural History Museum and colleagues.

Faherty and his colleagues used Webb to observe a sample of 12 cool brown dwarf stars.

These included object W1935, discovered by citizen scientist Dan Caselden who collaborated on the Backyard Worlds Zooniverse project, and object W2220, discovered using NASA’s Wide Field Infrared Survey Explorer.

Webb revealed in great detail that W1935 and W2220 appear to be close clones of each other in composition.

Also, the brightness, temperature, and spectral characteristics of water, ammonia, carbon monoxide, and carbon dioxide were similar.

A notable exception is that W1935 showed emission from methane, in contrast to the expected absorption feature observed for W2220. This was observed at infrared wavelengths, to which Webb is uniquely sensitive.

“We expected methane to be present because it’s everywhere in these brown dwarfs,” Faherty said.

“But instead of absorbing light, we found just the opposite. The methane was glowing. My first thought was, what the hell? Why is this object emitting methane?” Do you want it?

Astronomers used computer models to deduce what might be behind the emission.

Modeling work showed that W2220 has a predictable energy distribution in its atmosphere, becoming colder with increasing altitude.

On the other hand, W1935 produced surprising results. The best models supported a temperature inversion, where the atmosphere becomes warmer as altitude increases.

“This temperature inversion is really puzzling,” says Dr. Ben Burningham, an astronomer at the University of Hertfordshire.

“We’ve seen this kind of phenomenon on planets with nearby stars that can heat the stratosphere, but it’s outrageous to see something like this on a celestial body with no obvious external heat source. .

In search of clues, researchers looked to our backyard: the planets of our solar system.

The gas giant planet could serve as a proxy for what is seen happening 47 light-years away in the atmosphere of 1935 AD.

Scientists have noticed that planets like Jupiter and Saturn have significant temperature inversions.

Research is still ongoing to understand the causes of stratospheric heating, but leading theories about the solar system include external heating by auroras and internal energy transport from deep in the atmosphere, with the former being the leading explanation. ).

According to the research team, W1935 is the first aurora candidate outside the solar system with the signature of methane emission.

It is also the coldest aurora candidate outside the solar system, with an effective temperature of about 200 degrees Celsius (400 degrees Fahrenheit).

In our solar system, the solar wind is the main contributor to the auroral process, and active satellites like Io and Enceladus play the role of planets like Jupiter and Saturn, respectively.

W1935 does not have any companion stars, so stellar winds cannot contribute to this phenomenon. It is not yet known whether an active moon is responsible for her W1935's methane emissions.

“W1935 provides a spectacular expansion of solar system phenomena without any explanatory stellar illumination,” Faherty said.

“With Webb, we can actually ‘lift the lid’ on chemistry and figure out how auroral processes are similar or different outside of our solar system.”

The authors announced that findings this week’s AAS243243rd Meeting of the American Astronomical Society, New Orleans, USA.

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Jacqueline Faherty other. 2024. JWST exhibits the auroral features of frigid brown dwarfs. AAS243Abstract #4359

Source: www.sci.news

Webb finds small, free-floating brown dwarf in star-forming cluster IC 348

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The newly discovered brown dwarf is estimated to have a mass three to four times that of Jupiter, making it a strong candidate for the lowest mass free-floating brown dwarf ever directly imaged.

This image from Webb’s NIRCam instrument shows the central portion of star cluster IC 348. Image credits: NASA / ESA / CSA / STScI / K. Luhman, Pennsylvania State University / C. Alves de Oliveira, ESA.

Brown dwarfs are cold, dark objects that are between the size of gas giant planets and Sun-like stars.

These objects, also known as failed stars, have star-like properties even though they are too small to sustain hydrogen fusion reactions in their cores.

Typically, their masses are between 11 and 16 Jupiter (the approximate mass that can sustain deuterium fusion) and 75 and 80 Jupiter (the approximate mass that can sustain hydrogen fusion).

“One of the basic questions you’ll find in any astronomy textbook is: What is the smallest star? That’s what we’re trying to answer,” said Kevin, an astronomer at Penn State University.・Dr. Luman said.

The newly discovered brown dwarf resides in IC 348, a star cluster 1,000 light-years away in the constellation Perseus.

The cluster, also known as Collinder 41, Gingrich 1, and Theia 17, contains nearly 400 stars and is about 5 million years old.

IC 348 is part of the larger Perseus star-forming region, and although it is normally invisible to the naked eye, it shines brightly when viewed at infrared wavelengths.

Dr. Luhmann and his colleagues used the following method to image the center of the star cluster. Webb’s NIRCam device Identify brown dwarf candidates based on their brightness and color.

They followed up on the most promising targets using: Webb’s NIRSpec microshutter array.

This process created three interesting targets with masses between three and eight Jupiters and surface temperatures between 830 and 1,500 degrees Celsius.

Computer models suggest that the smallest of these weighs just three to four times as much as Jupiter.

ESA astronomer Dr Catalina Alves de Oliveira said: “With current models, it is very easy to create a giant planet in a disk around a star.”

“But in this cluster, the object is unlikely to form as a disc, but instead as a star, with three Jupiters having a mass 300 times less than the Sun.”

“Then we have to ask how the star formation process takes place at such a very small mass.”

Two of the brown dwarfs identified by the research team exhibit spectral signatures of unidentified hydrocarbons, molecules that contain both hydrogen and carbon atoms.

The same infrared signature was detected in the atmospheres of Saturn and its moon Titan by NASA’s Cassini mission.

It has also been observed in the interstellar medium, the gas between stars.

“This is the first time this molecule has been detected in the atmosphere of an object outside our solar system,” Dr de Oliveira said.

“Models for brown dwarf atmospheres do not predict their existence. We are observing objects that are younger and have lower masses than ever before, and we are seeing something new and unexpected.” .”

a paper Regarding the survey results, astronomy magazine.

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KL Luman other. 2023. JWST survey of planetary mass brown dwarfs in IC 348. A.J. 167, 19; doi: 10.3847/1538-3881/ad00b7

Source: www.sci.news