It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Tuesday, February 17, 2026
Shrinking cloud cover adds to accelerating Climate Crisis
Satellite data show declining low-level cloud cover over subtropical oceans, reducing the Earth’s reflectivity and accelerating the planet’s energy imbalance as global temperatures outpace climate model projections. / bne IntelliNews
Earth’s cloud cover is diminishing in key regions, reducing the planet’s ability to reflect sunlight back into space and adding to the accelerating Climate Crisis, research reported by Science found.
As bne IntelliNews reported, shrinking cloud cover is reflecting less sunlight from the and adding to the warming effect of Green House Gases (GHGs). Currently global warming is happening faster than all the 30-plus climate models used by the Paris Agreement to determine the rates of reduction of emissions. The United Nations’ Intergovernmental Panel on Climate Change (IPCC) says the 1.5°C – 2.0°C targets have already been missed and the world is on course to warm by 2.7°C-3.2°C in the coming decades.
Decreasing cloud cover with only bring that end point closer. Satellite observations and climate analyses suggest that low-lying marine clouds — particularly over subtropical oceans — have declined in recent decades, weakening what scientists describe as a critical planetary cooling mechanism. Because such clouds act as a mirror, reflecting incoming solar radiation, even small reductions can produce measurable warming effects.
The shrinking cloud cover is added to the earth’s energy imbalance (EEI) which is acting on top of the greenhouse effect of emitted gases like CO₂ and methane. More energy than ever before is coming into the planet (absorbed sunlight) than is going out (heat radiated to space), said the scientists. The earth’s energy imbalance (EEI) has escalated in the past decade, they said. The imbalance so far in the 2020s is almost double the rate during the study’s calibration period, from mid-2005 to mid-2015.
The findings come as global temperatures have repeatedly broken records, with the last three years being the hottest year in documented history. Researchers say the loss of reflective cloud cover may be helping to explain why temperatures are rising faster than the models predicted.
Scientists cited by Science report that changes are especially evident in stratocumulus cloud decks over the Pacific and Atlantic oceans. These bright, persistent cloud formations have historically offset a portion of greenhouse gas-driven warming. Their retreat means more heat is absorbed by darker ocean waters.
The causes remain under investigation. One hypothesis links the trend to cleaner shipping fuels. Regulations introduced by the International Maritime Organization in 2020 reduced sulphur emissions (SO₂) from marine fuel, cutting aerosol pollution that can seed cloud formation and increase cloud brightness. With fewer aerosols available, clouds may form less readily or reflect less sunlight.
Other researchers point to feedback loops within the climate system. As oceans warm, atmospheric circulation patterns can shift, thinning cloud layers and reinforcing additional warming. This self-reinforcing cycle is a longstanding concern in climate science because it could accelerate temperature rises beyond earlier expectations.
Clouds remain one of the biggest sources of uncertainty in climate modelling as they are not well understood, and small variations in their behaviour can alter projections of future warming by tenths of a degree Celsius or more. A sustained reduction in low-cloud cover would effectively increase the Earth’s climate sensitivity to greenhouse gas concentrations.
While further study is required to determine whether the recent decline represents a long-term shift or natural variability, researchers warn that the trend highlights the complexity of efforts to curb warming, as reductions in air pollution can produce unintended climatic side effects even as they deliver clear public health benefits.
Australia trapped under a “heat dome”, braces for extreme 50°C temperatures
High-pressure heat dome pushes Australian temperatures towards 50C, prompting catastrophic fire danger warnings in South Australia and Victoria / bne IntelliNews
Australia has found itself trapped under a “heat dome” that threats to send temperatures up above 50°C. Authorities are already warning residents to stay indoors during the day.
An intense heatwave has settled over the country as a vast high-pressure system covers the continent, pushing temperatures into extreme territory and prompting authorities to issue catastrophic fire danger warnings across parts of South Australia and Victoria.
Severe Weather Europe reported that the so-called heat dome has effectively sealed the continent, trapping and compressing hot air near the surface. The system has been reinforced by energy from Tropical Cyclone Luana, helping to drive temperatures towards what the forecaster described as “a scorching 50 °C”.
Under a heat dome, sinking air associated with high pressure warms as it descends, suppressing cloud formation and allowing solar radiation to intensify surface heating. AS bne IntelliNews reported, shrinking cloud cover is adding to the earth’s energy imbalance (EEI) and accelerating global heating adding to the greenhouse effect of emissions.
In inland regions where soils are already parched, the lack of moisture also limits evaporative cooling, creating a positive feedback loop in which heat further dries the ground, amplifying temperature extremes, according to meteorologists.
Towns including Ouyen and Mildura are bracing for temperatures approaching 48C. Authorities have warned that the conditions resemble those seen during the infamous 2019-2020 “Black Summer” when bushfires swept the country due to extreme heat. Prolonged heat and drought contributed to blazes that burned more than 24mn hectares and killed 33 people, with many more deaths linked to smoke exposure.
Severe Weather Europe said the event differs from a standard seasonal heatwave because it is being “sustained by a dangerous feedback loop” driven by dry soils and persistent high pressure.
Fire services in affected states have issued danger ratings at the top of their scale under Australia’s warning system, and urged residents in high-risk areas to activate bushfire survival plans. Extreme heat also poses risks to health, infrastructure and electricity networks, particularly in remote communities.
Chinese EV company CATL unveils a new super battery
CATL has unveiled a battery it says can charge in 12 minutes and retain 80% capacity after 1.5mn miles, potentially reshaping competition in the global electric vehicle market. / bne IntelliNews
Contemporary Amperex Technology Co Limited (CATL) has unveiled a new electric vehicle battery that it says can fully charge in 12 minutes and retain 80% of its capacity after 1.5mn miles, marking a potential breakthrough in durability and charging speed in the global EV market.
The Chinese battery manufacturer said the new system incorporates advanced thermal management, smart cooling and self-repair technologies designed to limit degradation over extended use. If validated at scale, the development could address two of the main barriers to wider electric vehicle adoption: charging time and battery longevity.
“12-minute charge with 1.5M mile degradation to only 80% capacity is game-changing if true - that's basically solving the two biggest EV adoption barriers simultaneously. CATL's likely using lithium iron phosphate with advanced thermal management and self-healing electrolytes. The real test is cost and scalability –”
CATL is already the world’s largest EV battery maker, supplying carmakers including Tesla, BMW and Volkswagen. Tesla currently offers eight years or 100,000 miles, whichever comes first, as a Battery Limited Warranty for its Model Y, highlighting the potential scale of improvement implied by CATL’s claims.
The company has previously commercialised lithium iron phosphate batteries, known for lower costs and improved safety compared with nickel-based chemistries, though typically at the expense of energy density. Industry analysts say advances in cell chemistry and thermal control have narrowed that gap in recent years.
Sodium-ion batteries are also in development as a lower-cost alternative to lithium-based technologies, aiming to reduce reliance on critical minerals and further drive down prices.
Sodium-ion (Na-ion) batteries offer a safer, lower-cost alternative to the lithium-ion systems that currently dominate the business, according to recent studies published in Advanced Materials and Advanced Functional Materials.
Li-ion batteries currently account for roughly 70% of the world’s rechargeable batteries, with the energy sector alone consuming over 90% of global supply, according to data from the International Energy Agency.
The long-sought breakthrough outlines a novel solid-state battery architecture that achieves 99.26% efficiency after 600 charge cycles, while eliminating lithium, cobalt, and flammable liquid electrolytes — long-standing weaknesses in current lithium-ion (Li-ion) designs.
Battery production costs have fallen by about 40% over the past year as a battery revolution gathers pace.
In parallel, research is under way into silver-ion batteries, which developers claim could potentially double capacity and enable faster charging than conventional lithium-ion systems, although such technologies remain at an earlier stage of commercial readiness.
China’s vast water diversion project reshapes growth in the arid north
South-to-North Water Transfer Project delivers 64.73bn cubic metres in a year, underpinning growth and urban expansion across northern China / bne IntelliNews
China’s South-to-North Water Transfer Project has delivered 64.73bn cubic metres of water to the country’s arid north over the past year, bringing cumulative transfers to more than 83bn cubic metres since operations began, according to official data released in November 2025. Nearly 118mn people now rely on the system for daily supply, as water security moves up the agenda in the midst of accelerating temperature rises and increasing extreme weather events.
Over the past five years alone, more than 52mn residents have been added to the project’s service area. The Middle Route — the most politically significant of the three channels — now forms the backbone of water provision for the Beijing-Tianjin-Hebei region, long constrained by chronic scarcity. The area holds just 7.2% of China’s water resources but supports almost one-third of its population.
China faces similar problems to the Western US states where a mounting water shortage threatens to become critical after several states with overlapping water interests failed to come to an agreement to make critical and deep cuts to their water usage, the Guardian reported.
This month seven states remained at a stalemate over who should bear the brunt of the enormous water cuts needed to pull the imperilled Colorado River back from the brink. Collectively they need to cut their usage by a quarter of face the prospect of not having enough water. But after months of talks no agreement was reached and now the outlook for water supply for a region that includes cities like Las Vegas looks bleak.
China’s northern region faces similar imbalances but decisive government action appears to have dealt with the biggest problems after groundwater overdraft, land subsidence and seasonal river depletion was already limiting industrial expansion.
Beijing’s groundwater table has risen by more than 13 metres over the past decade, with official figures indicating that over-extraction zones have been eliminated. More than 11.8bn cubic metres of ecological water have been channelled into 50 northern rivers, including the Hutuo and Juma, helping reverse years of environmental degradation.
The easing of resource constraints has gone hand in hand with a broader spatial reorganisation of the Beijing-Tianjin-Hebei economic cluster, which generated CNY11.5tn ($1.6 trillion) in gross domestic product in 2024. Cities have literally been rebuilt on the basis of resource availability to produce sustainable cities that could have otherwise died.
At the centre of this strategy lies Xiong’an New Area, launched in 2017 to absorb Beijing’s non-capital functions. The district has attracted more than CNY830bn ($115bn) in cumulative investment and seen 4,700 buildings constructed.
Institutional infrastructure is following. Beijing No.4 High School has opened a campus in Xiong’an, while Xiong’an Xuanwu Hospital has recorded 200,000 patient visits. The Xiong’an Zhongguancun Science Park hosts more than 130 enterprises. Fifteen Beijing universities, including Beijing Jiaotong University and the University of Science and Technology Beijing, are establishing branch campuses under a “one university, two campuses” model, with capacity for about 250,000 students by 2030.
Researchers from Capital University of Economics and Business wrote in the 2025 Beijing-Tianjin-Hebei Bluebook that deeper integration of education, technology and talent would enable the region to shift from “scale pursuit to capability leap”. Water security underpins that ambition, removing what had been a binding constraint on laboratories, semiconductor fabrication plants and urban expansion.
The infrastructure itself is evolving. Operators have introduced digital twin systems for real-time monitoring, while robotics and AI tools conduct inspections along the route. A supplementary Yangtze-to-Han River diversion, now under construction, will further reinforce supply. By 2027, operators aim to achieve zero-carbon operations along the Middle Route.
The completed Middle Route can transport 9.5bn cubic metres of water annually. For policymakers, the question is no longer whether northern China can sustain its population, but what form of growth it will pursue now that its most basic resource constraint has been eased.
China overtakes the US in nuclear submarine production, says IISS
China has increased nuclear-powered submarine production at its Bohai shipyard, surpassing US launch numbers and tonnage between 2021 and 2025, according to IISS. / bne IntelliNews
China has long ago overtaken the US when it comes to the navy, but now Beijing has also overhauled the US in submarines.
China has rapidly expanded its nuclear-powered submarine production, surpassing US launch numbers and tonnage between 2021 and 2025, according to the International Institute for Strategic Studies (IISS), highlighting a shift in the balance of naval industrial capacity.
In an analysis published on February 16, IISS said Beijing’s shipyards, particularly at Bohai, have increased output at a pace that exceeds that of the US over the past four years. Although qualitative differences compared with US and European designs persist, the increasing number of Chinese submarines presents a growing challenge for Western countries struggling to expand their own production.
China’s expansion reflects sustained investment in naval modernisation by President Xi Jinping, who has prioritised the People’s Liberation Army Navy as part of a broader push to project power further from the mainland. Satellite imagery and open-source assessments cited by IISS indicate multiple hulls under construction simultaneously at the Bohai Shipyard, suggesting improvements in modular construction and industrial throughput.
A maritime arms race is well underway that the Chinese navy is winning. China currently has more ships in its fleet than the US and is adding the equivalent of the entire French navy every four years.
China built between 115 and 125 military warships from 2020 to 2025, averaging 19 to 21 units per year. This rate surpasses the combined production of powers such as the United States, Japan, and South Korea, which together added only about 46 to 51 ships in the same period. Even if we added European production to that of the US, South Korea, and Japan, it wouldn't change much. The Chinese fleet now totals approximately 395 combat ships, eclipsing the 296 of the US, the roughly 140 of South Korea, and the 103 of Japan.
The story is similar in Chinese anti-ship ballistic missiles, where it also has a clear lead over the US, which has been asleep at the wheel, according to an analysis by bne IntelliNews military analyst Patricia Marins.
China has been trailing in submarine production until now. While US submarines are widely regarded as quieter and more technologically advanced, Washington has faced delays and cost overruns in its Virginia-class programme, according to IISS. The US Navy has acknowledged production bottlenecks in its industrial base, complicating efforts to meet domestic fleet targets while also fulfilling commitments under the AUKUS security pact with the UK and Australia.
European producers face similar constraints. The UK’s Astute-class and forthcoming Dreadnought-class submarines have encountered schedule pressures, while France’s Naval Group is balancing domestic and export orders.
IISS noted that although qualitative differences compared with US and European designs persist, the sheer scale of China’s output is altering strategic calculations. A larger fleet enhances Beijing’s ability to maintain continuous at-sea deterrence patrols and expand operations in the western Pacific.
One of the major constraints on the Chinese submarine fleet is that China has no deep-water ports on its coastline. The South China Sea is shallow, making any submarine launch from a Chinese port visible to US satellites and potentially vulnerable to missile strikes. However, the eastern coast of Taiwan drops off to several thousand meters almost immediately making it perfect for a submarine base where launches would immediately disappear into deep water making them untrickable – giving Beijing a significant military motivation for taking back control of the island state.
Sarajevo protests enter fourth day after deadly tram crash
Protests in Bosnia’s capital entered a fourth day on February 16 as demonstrators demanded accountability after a tram derailment killed a 23-year-old man and seriously injured several others, including a teenage girl who lost a leg.
The protests were triggered by the February 12 crash, when a tram derailed at speed near a stop, killing Erdoan Morankic and injuring four other passengers.
High school and university students again gathered in central Sarajevo, chanting “Justice, justice”, as they called for the release of maintenance records, video footage from the tram and the withdrawal of unsafe vehicles from service, according to local media reports.
The demonstrations have already led to political fallout. Sarajevo Canton Prime Minister Nihad Uk resigned on Sunday, causing the cantonal government to collapse, while Senad Mujagic, director of the city’s public transport company GRAS, stepped down on February 16.
Uk said his decision reflected the pressure from young protesters, who organised the rallies through Instagram pages.
“When I took over the position of prime minister of Sarajevo Canton, in my address, I primarily spoke about young people. How to be their support, how to turn towards their future and not our past. Young people have taken to the streets,” Uk said in his statement, published by N1.
He added: “The message of my fellow citizens, the message of young people, is important to me. Certainly more important than my position. And when I choose between the voice and courage of young people on one side and my position on the other, the choice is clear.”
Organisers said the protests were aimed at showing unity and solidarity with the victims and forcing authorities to accept responsibility.
They have outlined four key demands: full transparency of the investigation, including maintenance documentation and onboard video; the immediate withdrawal of unsafe trams; the resignation of officials responsible for transport oversight; and long-term reforms to create a safe and reliable public transport system.
Monday, February 16, 2026
SPACE/COSMOS
Europe's quick-fit spacesuit to be tested aboard ISS by France's Adenot
A prototype European space suit designed to be slipped on in under two minutes is set for testing aboard the International Space Station, where French astronaut Sophie Adenot, now in orbit for her first long-duration mission, will try it out in microgravity.
The prototype, known as the EuroSuit, is designed to protect astronauts inside spacecraft while making suits faster and easier to put on.
The project brings together the French National Centre for Space Studies (CNES), start-up Spartan Space, the space medicine institute Medes and sporting goods company Decathlon, which developed the textile and ergonomic elements.
Adenot reached the ISS on Saturday after a roughly 34-hour journey from Cape Canaveral in Florida aboard a SpaceX spacecraft. The capsule docked with the station, orbits about 400 kilometres above Earth, at 9:15pm Paris time.
“I am proud to bring France and Europe along on this incredible adventure that transcends borders. Count on me to share every step with you and bring a sparkle to the eyes of the French people,” Adenot said shortly afterwards.
The 43-year-old – the second French woman to reach space – will test the EuroSuit prototype in microgravity by putting it on alone against the clock in less than 120 seconds.
She will then handle small objects while wearing it, use a touchscreen tablet to assess grip and dexterity, then remove the suit before providing feedback.
Adenot did not wear the EuroSuit for launch because SpaceX provides the suit astronauts wear for take-off. Instead, the prototype will be tested in microgravity aboard the station during the mission.
The CNES is coordinating the microgravity testing for the European Space Agency (ESA) and Spartan Space is leading the work as prime contractor, while Medes is developing real-time monitoring equipment.
Alongside the suit work, Adenot will also test a system that uses artificial intelligence and augmented reality to help astronauts carry out their own medical ultrasounds.
For Decathlon, founded in 1976 and based in Villeneuve-d’Ascq in northern France, the project marks a step beyond sports and leisure equipment into astronaut clothing.
The company was a partner of the Paris Olympic Games, but this time it is working on equipment with far tighter technical constraints.
The teams focused in particular on helmets adapted to each astronaut’s body shape and on ways to adjust the suit’s length to match the way the human body stretches in microgravity.
“Engineers, designers, textile specialists, 3D printing experts and mechanical engineers. Passion took hold of everyone. When the project arrived on our desks, it was quite easy to recruit people. We even had to select a ‘dream team’.”
Europe’s future missions
The partnership took shape from the end of 2023, Haquet said, when Spartan Space approached Decathlon. They then spent 2024 learning how to work together with CNES before moving into a more intensive design phase.
“From the end of January 2025, we launched a creative sprint, brought the talent together around a table and started designing. We are taking on space standards. We met that challenge by designing a suit in 10 months,” Haquet said.
He added that ESA does not have a design charter for astronaut suits, only a graphic charter, and that defining the aesthetic spirit of the suit was part of Decathlon’s mandate.
ESA is also working with Pierre Cardin on other projects, and NASA is working with Prada.
“It’s interesting to see Decathlon measure itself against long-established luxury brands, when it comes to the strength of its in-house designers,” Haquet said.
Under the suit, Adenot will wear a base layer described as a kind of “layer zero” pyjama made with a seamless process, using a single thread knitted from trousers to top. “You don’t give off any sweat smell with this garment as it absorbs them,” Haquet said.
Being able to suit up independently and shape a suit in under two minutes “does not exist today in the space sector”, he added. “Our suit isn’t yet functional.”
The wider question is how far ESA wants to go on autonomous human spaceflight.
A joint statement from the project partners said the aim is “to imagine the protective and comfort equipment for the European astronauts of tomorrow”.
The suit is designed to improve comfort and speed, and above all to protect the astronaut during “critical phases”. Ground tests are planned through next year and for now the goal is to validate the design and ergonomics.
Contributed by Kea Giles, Managing Editor, Geology
Boulder, Colo., USA: What appears to be a single volcanic eruption is often the result of complex processes operating deep beneath the surface, where magma moves, evolves, and changes over long periods of time. To fully understand how volcanoes work, scientists study the volcanic products that erupt at the surface, which can reveal the hidden magmatic systems feeding volcanic activity.
New research published recently in Geology shows that this complexity also applies to Mars. Recent high-resolution morphological observations and mineral analyses provided from orbit revealed that some of the planet’s youngest volcanic systems experienced a far more intricate eruptive history than scientists once thought. Rather than forming during single, short-lived eruptions, these volcanoes were shaped by long-lasting and evolving magma systems beneath the martian surface.
An international research team, including scientists from Adam Mickiewicz University in PoznaÅ„, the School of Earth, Environment and Sustainability (SEES) at the University of Iowa, and the Lancaster Environment Centre, investigated a long-lived volcanic system located south of Pavonis Mons—one of Mars’ largest volcanoes. By combining detailed surface mapping with orbital mineral data, the team reconstructed the volcanic and magmatic evolution of this system in unprecedented detail.
“Our results show that even during Mars’ most recent volcanic period, magma systems beneath the surface remained active and complex,” says Bartosz Pieterek of Adam Mickiewicz University. “The volcano did not erupt just once—it evolved over time as conditions in the subsurface changed.”
The study shows that volcanic system developed through multiple eruptive phases, transitioning from early fissure-fed lava emplacement to later point-source activity that produced cone-forming vent. Although these lava flows appear different on the surface, they were supplied by the same underlying magma system. Each eruptive phase preserved a distinct mineral signature, allowing scientists to trace how the magma changed through time.
“These mineral differences tell us that the magma itself was evolving,” Pieterek explains. “This likely reflects changes in how deep the magma originated and how long it was stored beneath the surface before erupting.”
Because direct sampling of Martian volcanoes is currently not possible, studies like this provide rare insight into the structure and evolution of the planet’s interior. The findings highlight how powerful orbital observations can be in revealing the hidden complexity of volcanic systems—on Mars and on other rocky planets.
The Geological Society of America (GSA) is a global professional society with more than 18,000 members across over 100 countries. As a leading voice for the geosciences, GSA advances the understanding of Earth's dynamic processes and fosters collaboration among scientists, educators, and policymakers. GSA publishes Geology, the top-ranked “geology” journal, along with a diverse portfolio of scholarly journals, books, and conference proceedings—several of which rank among Amazon’s top 100 best-selling geology titles.
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Journal
Geology
Article Title
Spectral evidence for magmatic differentiation within a Martian plumbing system
Chinese scientists develop distributed intercity quantum sensor network to expand dark matter research
Ordinary visible matter accounts for only about 4.9 percent of the universe, while dark matter makes up about 26.8 percent. Axions are hypothetical, extremely light particles—with field-like properties—that may help us understand dark matter. Researchers speculate that axion fields formed topological defects during phase transitions in the early universe. In turn, these defects are expected to interact with nuclear spins and induce signals as the Earth crosses them. Detecting these signals could thus be key to understanding dark matter; however, such signals are extremely weak and of short duration.
In order to identify such signals, researchers from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences and their collaborators developed the first intercity nuclear-spin-based quantum sensor network, thereby experimentally exceeding astrophysical observation constraints on dark matter associated with axion topological defects. The study was published in Nature on January 28.
In this experiment, the researchers developed a nuclear-spin quantum precision measurement that "stores" microsecond-scale axion-induced signals in a long-lived nuclear-spin coherent state, enabling a readout signal on the scale of minutes. Based on a self-developed quantum spin amplification technique, they enhanced the weak dark-matter signal by at least 100-fold and increased the sensitivity of spin rotation to about 1 μrad, about four orders of magnitude higher than previous techniques.
Furthermore, the researchers created the first intercity nuclear-spin based quantum sensor network to discriminate dark matter signals. This network consisted of five nuclear-spin quantum sensors geographically distributed across Hefei and Hangzhou with a baseline distance of approximately 320 km, which were synchronized using Global Positioning System (GPS) time.
Although no statistically significant topological-defect-crossing event was recorded during two months of observation, the researchers set the most stringent constraints on axion–nucleon coupling across an axion mass range from 10 peV to 0.2 μeV, achieving 4.1 × 1010 GeV at 84 peV.
This study provides the first laboratory experiment to exceed astrophysical constraints on axion topological-defect dark matter, opening up the possibility of examining unexplored parameter space. It provides a new way to probe topological-defect dark matter as well as a new direction for searches on broad beyond-Standard Model physics such as axion stars and axion strings.
In 2014, a NASA telescope observed as the infrared light emitted by a massive star in the Andromeda galaxy gradually grew brighter. The star glowed more intensely with infrared light for around three years before fading dramatically and disappearing, leaving behind a shell of dust. Although a telescope captured the phenomenon at the time, it took years for scientists to notice it.
Now, a research team led by Kishalay De, a Columbia astronomy professor, has an explanation of what they saw: It was a star collapsing and giving birth to a black hole—an event that astronomers have anticipated for decades, but have had limited convincing observational evidence for. The findings were published today in the journal Science.
The star appears to have undergone direct collapse, turning into a black hole without first exploding and becoming a supernova, long-believed to be a common way for stars to become black holes.
“This has probably been the most surprising discovery of my life,” De said. “The evidence of the disappearance of the star was lying in public archival data and nobody noticed for years until we picked it out.”
The star, a massive, hydrogen-depleted supergiant, named M31-2014-DS1, was in the Andromeda galaxy, which is the closest major galaxy to the Milky Way, and about 2.5 million light years from earth. When newly formed, the star was around 13 times the weight of the sun. At the time of its death, it was close to five times the mass of the sun., having shed most of its mass via powerful winds during its life.
“The dramatic and sustained fading of this star is very unusual, and suggests a supernova failed to occur, leading to the collapse of the star’s core directly into a black hole,” De said.
“Stars with this mass have long been assumed to always explode as supernovae,” De said. "The fact that it didn’t suggests that stars with the same mass may or may not successfully explode, possibly due to how gravity, gas pressure, and powerful shock waves interact in chaotic ways with each other inside the dying star.”
The manner in which the star turned into a black hole suggests that at the end of its life, its inner core was not pushed out in a normal supernova explosion and instead underwent a complete inward collapse.
The process of direct collapse may have been seen once before, in around 2010, in the galaxy NGC 6946, which is about 10 times further away than this star. But its exact nature has been unclear and debated, because it was 100 times fainter and there was not as high quality data about it.
“We've known that black holes must come from stars. With these two new events, we're getting to watch it happen, and are learning a huge amount about how that process works along the way,” said Morgan MacLeod, a lecturer on astronomy at Harvard, who was De’s co-author on the paper.
Black holes were first theorized more than 50 years ago, and today we know of dozens in our own galaxy and hundreds of such sources detected from gravitational wave observations in the distant universe. However, scientists still do not have any clear consensus on what stars turn into black holes and how that process plays out. This discovery provides the clearest insights into this and indicates that this kind of stellar collapse may happen more often than scientists had thought.
The team discovered the star by analyzing archival data from NASA’s NEOWISE mission. They used a prediction from the 1970s that theorized that when a star underwent direct collapse, it would leave behind a faint infrared glow caused by the dying gasp of the star shedding its outer layers and becoming enshrouded in dust.
They conducted the largest study of variable infrared sources ever done, tracking every star in the Milky Way and other local galaxies to look for these events, and eventually came across M31-2014-DS1. Further analysis showed that the star fit their predictions perfectly.
“Unlike finding supernovae which is easy because the supernova outshines its entire galaxy for a few weeks, finding individual stars that disappear without producing an explosion is remarkably difficult,” De said.
“It comes as a shock to know that a massive star basically disappeared (and died) without an explosion and nobody noticed it for more than five years,” De said. “It really impacts our understanding of the inventory of massive stellar deaths in the universe. It says that these things may be quietly happening out there and easily going unnoticed.”
Gravitationally lensed starlight (orange) by a supermassive black hole binary. The Einstein ring is shown in blue. Image credit: Image created by Hanxi Wang.
Researchers at Oxford University and the Max Planck Institute for Gravitational Physics (Albert Einstein Institute) are proposing a new way to observe tightly bound supermassive black hole binaries. Formed naturally when galaxies merge, only widely separated systems have confidently been observed to date. In a paper published today in Physical Review Letters, the researchers suggest hunting down the hidden systems by searching for repeating flashes of light from individual stars lying behind the black holes as they are temporarily magnified by gravitational lensing as the binary orbits.
Supermassive black holes reside at the centres of most galaxies. When two galaxies collide and merge, their central black holes eventually form a bound pair, known as a supermassive black hole binary. These systems play a crucial role in galaxy evolution and are among the most powerful sources of gravitational waves in the Universe. While future space-based gravitational-wave observatories will be able to probe such binaries directly, researchers are now showing that they may already be detectable using existing and upcoming electromagnetic surveys.
‘Supermassive black holes act as natural telescopes,’ said Dr Miguel Zumalacárregui from the Max Planck Institute for Gravitational Physics. ‘Because of their enormous mass and compact size, they strongly bend passing light. Starlight from the same host galaxy can be focused into extraordinarily bright images, a phenomenon known as gravitational lensing.’
For a single supermassive black hole, extreme lensing occurs only when a star lies almost exactly along the line of sight. In contrast, a supermassive black hole binary acts as a pair of lenses. This produces a diamond-shaped structure, known as a caustic curve, along which stars can experience dramatic magnification. In theory, the magnification becomes infinite for a point-like source; in practice, it is limited by the finite size of the star.
‘The chances of starlight being hugely amplified increase enormously for a binary compared to a single black hole,’ said Professor Bence Kocsis from the University of Oxford’s Department of Physics and a co-author of the study.
A further key difference is that black hole binaries are not static. The pair orbits under gravity, and according to Einstein’s theory of general relativity, the system slowly loses energy by emitting gravitational waves. As a result, the binary separation shrinks over time and the orbit gradually speeds up.
Graduate student Hanxi Wang is in Professor Kocsis’ group and led the study: ‘As the binary moves, the caustic curve rotates and changes shape, sweeping across a large volume of stars behind it. If a bright star lies within this region, it can produce an extraordinarily bright flash each time the caustic passes over it. This leads to repeating bursts of starlight, which provide a clear and distinctive signature of a supermassive black hole binary.’
The researchers show that the timing and brightness of these bursts are not random. As the binary inspirals, gravitational-wave emission subtly alters the caustic structure, imprinting a characteristic modulation in both the frequency and peak brightness of the flashes. By measuring these patterns, astronomers could infer key properties of the underlying black hole binary, including its masses and orbital evolution.
With powerful wide-field surveys coming online such as the Vera C Rubin Observatory and the Nancy Grace Roman Space Telescope, researchers are optimistic that such repeating lensing bursts could be observed in coming years.
‘The prospect of identifying inspiraling supermassive black hole binaries years before future space-based gravitational wave detectors come online is extremely exciting,’ concludes Professor Kocsis. ‘It opens the door to true multi-messenger studies of black holes, allowing us to test gravity and black hole physics in entirely new ways.’
The study ‘Black holes as telescopes: Discovering supermassive binaries through quasi-periodic lensed starlight’ has been published today (12 February) in Physical Review Letters
Oxford University has been placed number 1 in the Times Higher Education World University Rankings for the tenth year running, and number 3 in the QS World Rankings 2024. At the heart of this success are the twin-pillars of our ground-breaking research and innovation and our distinctive educational offer.
Oxford is world-famous for research and teaching excellence and home to some of the most talented people from across the globe. Our work helps the lives of millions, solving real-world problems through a huge network of partnerships and collaborations. The breadth and interdisciplinary nature of our research alongside our personalised approach to teaching sparks imaginative and inventive insights and solutions.
Through its research commercialisation arm, Oxford University Innovation, Oxford is the highest university patent filer in the UK and is ranked first in the UK for university spinouts, having created more than 300 new companies since 1988. Over a third of these companies have been created in the past five years. The university is a catalyst for prosperity in Oxfordshire and the United Kingdom, contributing around £16.9 billion to the UK economy in 2021/22, and supports more than 90,400 full time jobs.
The Very Large Array Low-band Ionosphere and Transient Experiment (VLITE) team, Namir Kassim, left, Emil Polisensky, Simona Giacintucci, Joe Helmboldt and Tracy Clarke, pose for a group photo at the U.S. Naval Research Laboratory in Washington, Feb. 10, 2026. VLITE is marking its 11th year of operation, recording the low-frequency radio sky across an entire solar cycle and providing Naval Research Laboratory scientists with long-term ionospheric data. (U.S. Navy photo by Sarah Peterson)
A collaboration between the U.S. Naval Research Laboratory (NRL) and the National Radio Astronomy Observatory (NRAO), VLITE operates alongside the VLA without interrupting its primary science mission. While astronomers study distant galaxies and black holes, VLITE collects a parallel stream of low-frequency data, building one of the most extensive continuous records of the dynamic radio sky.
The data has practical implications. Variations in space weather can affect satellite communications, GPS, radar and long-distance radio systems. Originally conceived as an opportunistic add-on, VLITE has become a sustained observing program with both scientific and operational value.
“VLITE was designed to take advantage of opportunity,” said Tracy Clarke, Ph.D., an NRL research astronomer and VLITE lead. “We thought it might last a few years, but eleven years later it’s still ongoing. The longer it ran the more valuable it became. Time reveals scientific discoveries that you can’t anticipate.”
Monitoring the Ionosphere Across a Solar Cycle
Because VLITE observes at low radio frequencies, its signals are shaped both by distant astrophysical sources and by Earth’s ionosphere, the charged upper atmosphere that affects radio propagation.
Over 11 years, VLITE has recorded data spanning an entire solar cycle, capturing periods of both high and low solar activity.
“There are disturbances that occur when the sun is quiet and others that occur when it’s active,” said Joe Helmboldt, Ph.D., an ionospheric scientist in NRL’s Remote Sensing Division. “If you want reliable statistics, you have to observe across that full range of conditions.”
That extended coverage has enabled researchers to move beyond isolated case studies.
“We’ve gone from studying single events to identifying the physical processes that generate those disturbances,” Helmboldt said. “Short-term experiments show what’s happening at a moment in time. VLITE shows how the ionosphere behaves over years.”
Precision Sources and Navigation Potential
VLITE also monitors millisecond pulsars, rapidly rotating neutron stars that emit extremely stable radio pulses.
“Millisecond pulsars are among the most precise natural timing sources known,” said Emil Polisensky, NRL Ph.D., who supports VLITE’s transient detection and cataloging efforts. “Long-term monitoring helps us better understand their stability and potential applications.”
Because some pulsars are more stable than atomic clocks, they can serve as natural navigation beacons.
“You can use them analogously to GPS satellites,” Polisensky said. “In principle, a spacecraft could navigate around Earth, the Moon or even deeper into the solar system using pulsars.”
As the number of VLITE antennas expands from 18 to 23 by the end of this year, the system’s sensitivity will increase, improving its ability to detect rare and faint objects. “Greater sensitivity means we can find more exotic sources,” Polisensky said.
Turning Signals into Science
Each time VLITE collects data, Wendy Peters’ computer code goes to work. She is an NRL data processing and imaging pipeline developer. The custom code she developed automatically processes incoming signals, calibrates them, and prepares them for archiving.
Within about 48 hours, the data are stored and made available to researchers at a pace that requires constant monitoring as observations continue around the clock.
“The system doesn’t stop,” Peters said. “As new data comes in, the code has to keep up processing, organizing, and ensuring everything is accessible and reliable.”
Over 11 years, that steady flow has grown into a vast, searchable archive, sustained through continuous refinement and disciplined software engineering.
A Model of Efficient Collaboration
VLITE operates through a long-running partnership between NRL and NRAO. While the VLA conducts its primary observations, VLITE collects low-frequency data simultaneously, an approach known as commensal observing.
“The beauty of commensal observing is efficiency,” Clarke said. “We’re expanding scientific return from existing infrastructure. We’ve maintained it and invested in it. The VLITE approach is being evaluated internationally as a framework for similar systems.”
Over more than a decade, VLITE has accumulated tens of thousands of hours of observing time and repeatedly imaged nearly the entire sky visible to the VLA. The resulting archive includes millions of processed data products that support studies of astrophysical transients, ionospheric structure and celestial reference frame source stability.
“As a scientist, you want to pass on what you’ve learned,” Peters said. “Helping students experience discovery firsthand is one of the most rewarding parts of this work.”
The VLITE team is now developing polarization imaging capabilities, which would enhance detection of certain transient events and pulsars.
“There are many transient phenomena that are highly polarized,” Polisensky said. “Polarization imaging would make searching for new millisecond pulsars significantly more effective.”
VLITE demonstrates how sustained engineering and collaboration can expand scientific insight without competing for observing time.
“We’ve built something that continues to deliver value year after year,” Helmboldt said. “That consistency is what makes it powerful.”
After 11 years VLITE continues to listen, capturing a dynamic universe in motion and reinforcing the value of long-term vision, sustained collaboration and quiet innovation.
“We’ve got a small team, but they are a remarkable group of people that have been able to make this a success.” said Clarke, “I’m really proud of that.”
About the U.S. Naval Research Laboratory
NRL is a scientific and engineering command dedicated to research that drives innovative advances for the U.S. Navy and Marine Corps from the seafloor to space and in the information domain. NRL, located in Washington, D.C. with major field sites in Stennis Space Center, Mississippi; Key West, Florida; Monterey, California, and employs approximately 3,000 civilian scientists, engineers and support personnel.
NRL offers several mechanisms for collaborating with the broader scientific community, within and outside of the Federal government. These include Cooperative Research and Development Agreements (CRADAs), LP-CRADAs, Educational Partnership Agreements, agreements under the authority of 10 USC 4892, licensing agreements, FAR contracts, and other applicable agreements.
For more information, contact NRL Corporate Communications at NRLPAO@us.navy.mil.
Method of Research
Observational study
Two component self-interacting dark matter model explains both dwarf galaxy cores and strong gravitational lensing puzzles
Dark matter is one of the most important and most mysterious questions in modern astronomy. Although dark matter cannot be seen or touched, it profoundly influences the formation and evolution of galaxies through gravity. For a long time, scientists have widely adopted the “cold dark matter” model to describe how cosmic structures form. However, as observational precision has improved, a number of small-scale phenomena have emerged that do not fully align with the predictions of this classical framework.
For example, in some dwarf galaxies, dark matter appears unusually “diffuse,” with a relatively low central density. In contrast, observations of strong gravitational lensing have revealed extremely dense dark matter substructures whose compactness far exceeds what traditional models would predict. These two types of phenomena have long coexisted, yet they are difficult to explain with a single physical mechanism.
Recently, a new study by physicists from Purple Mountain Observatory, CAS, has offered an intriguing answer: dark matter may not be a single component, but instead consist of particles with different masses.
The researchers propose a “two-component self-interacting dark matter” model. In this scenario, dark matter includes at least two types of particles—one heavier and one lighter—which interact not only through gravity but can also undergo direct collisions. It is this additional interaction that gives rise to a process known as “mass segregation.”
Put simply, over time, heavier dark matter particles tend to sink toward the centers of galaxies, while lighter particles preferentially diffuse outward. This process is analogous to what happens in star clusters, where massive stars migrate inward and low-mass stars move to larger radii.
Using high-resolution numerical simulations and detailed theoretical modeling, the research team found that this mass-segregation effect can naturally reproduce a wide range of observational results. In dwarf galaxies, it leads to dark-matter cores with low central densities, consistent with the latest observations of galaxy clustering. In more complex and denser environments, some dark matter halos gradually become more compact, forming high-density structures capable of producing strong gravitational lensing effects. More importantly, the model can significantly enhance the probability of small-scale gravitational lensing. Mass segregation increases the concentration of dark matter in key regions, making dark-matter substructures more effective at “magnifying” the light from background galaxies. This helps alleviate the long-standing problem that observations seem to show too many small-scale strong lensing events.
The researchers emphasize that their work suggests several seemingly contradicting small-scale cosmological anomalies may, in fact, point to the same conclusion: the internal properties of dark matter are richer and more complex than previously assumed.
As future astronomical surveys and gravitational lensing observations reach ever higher precision, scientists may be able to use these “cosmic magnifying glasses” to further test whether dark matter is truly composed of multiple components. Perhaps in the not-too-distant future, our understanding of dark matter will undergo a pivotal transformation.
This study represents the second work by the Purple Mountain Observatory research team on two-component self-interacting dark matter and was recently published in Science Bulletin. In an earlier study, the team systematically investigated the impact of mass segregation on the diversity of core density distributions in dwarf galaxies, with the results published in Physical Review D. The authors of the paper include: Daneng Yang, Yi-Zhong Fan, Siyuan Hou, and Yue-Lin Sming Tsai.
Purple Mountain Observatory of the Chinese Academy of Sciences is one of China’s leading institutions for dark matter research. It undertakes national research missions in the field of indirect dark matter detection based on the DAMPE (Wukong) satellite and has long been engaged in astrophysics and cosmology research, with significant impact in areas such as dark matter and galaxy evolution.
