Large patches of open water were visible just 37 miles (60 kilometers) from the North Pole on Aug. 29, a NASA satellite image shows. Although this doesn't necessarily mean that Arctic ice is worse off this year than the past few years, the image reveals how severely climate change is affecting the region, experts say.

The image is from the NASA Worldview satellite photo browsing tool and was shared last week on the blog Arctic News. The patches are "quite striking," but it's not the first time that water has encroached upon Arctic ice in this way, said Julienne Stroeve, a professor of polar observation and modeling at University College London.

"We can see open water at times at the North Pole but I don't think it's ever been this extensive," Stroeve told Live Science in an email. For instance, the central Arctic Ocean and regions north of 80 degrees north latitude, an imaginary line that crosses Canada's Ellesmere Island and Spitsbergen in Norway, were highly fragmented in early September 2016.

The time of year is one reason water is now visible in this region, said Zachary Labe, a climate scientist at Climate Central, a nonprofit news organization that analyzes and reports on the climate. "By the end of summer, the sea ice generally becomes more fragmented, with areas of open water appearing more widespread between pieces of sea ice," Labe told Live Science in an email.

This means that local weather conditions and ocean currents can create large gaps between ice floes, Labe said. For example, strong winds can push ice fragments together or pull them apart, leading areas of water to widen or close within hours or days.

"Individual satellite images from around the North Pole in just the last two weeks show dramatic changes in the amount and location of visible open water," he noted.

The current extent of Arctic sea ice isn't particularly low when compared with record-setting years, but that's now very changeable due to the diffuseness of the ice, Stroeve said. "Winds could change and compress the ice into a more compact ice cover leading to sudden drops in total extent," she said.

There is no specific distance from the North Pole at which open water should normally stop, because Arctic conditions can vary substantially from year to year, Labe said. However, the summer ice has become thinner and more fragile in recent years, so open water is consistently reaching closer to the North Pole than it did before.

"To me, this image doesn't necessarily show that conditions are dramatically worse this year compared to other recent years," Labe said. "Instead, it represents a worrying snapshot of a very different Arctic Ocean than only a few decades ago and one that is quickly changing over time."

The Arctic is warming nearly four times faster than the global average. Some of the northernmost regions that have historically boasted expansive, thick and persistent ice at the end of summer now have young, brittle ice floes instead, Labe said.

"The broader implications of more open water across the Arctic Ocean are wide-ranging, from changes in local weather and ocean conditions to impacts on marine ecosystems and greater coastal risks like erosion and flooding for Arctic communities," he said.

Scientists expect that sea ice will start to refreeze by mid- to late September, closing at least some of the gaps.

Chemotherapy can save lives, but for many cancer patients, it leaves behind a painful legacy: damaged nerves that burn, tingle or go numb. Now, researchers report that a psychedelic compound may protect those nerves — not through its mind-bending effects, but by helping neurons keep their internal power supplies moving.

A new mouse study, published Thursday (Sept. 3) in the journal Science, suggests that psilocybin, the psychedelic compound in "magic mushrooms," may help prevent this painful and sometimes permanent side effect of chemotherapy, known as chemotherapy-induced peripheral neuropathy (CIPN).

In experiments in mice, psilocybin prevented nerve damage from CIPN that can cause pain, numbness and heightened sensitivity to cold and touch. Two doses of the drug given prior to chemotherapy garnered protection that persisted through as many as six rounds of the cancer treatment, according to the study.

CIPN affects roughly one-third to one-half of people receiving certain chemotherapies, said Dr. Thomas Strouse, a professor of clinical psychiatry and a neuropathy researcher at UCLA who was not involved in the study. In severe cases, the neuropathy can force doctors to reduce or stop chemotherapy. It can also contribute to mobility problems, which raise the risk of falls and fractures.

"It's a big deal, big problem," Strouse said. Researchers have been searching for a way to prevent it for a long time, he added.

Keeping nerve cells fueled

Initially, the researchers weren't looking for a neuropathy treatment, said study co-author Dr. Moran Amit, a cancer surgeon and researcher at The University of Texas MD Anderson Cancer Center. His team was investigating whether compounds that promote neuroplasticity — the nervous system's ability to change and adapt — might protect nerves and improve existing cancer treatments.

After testing several psychedelic compounds, they "very early on focused on psilocybin because this was the most effective one" for relieving neuropathy symptoms, Amit told Live Science. The psychedelic has been explored as a treatment for psychiatric disorders such as depression, in which it might promote "hyperconnectivity" between certain brain regions.

In the new study, protection against CIPN emerged as an unexpected effect of the drug.

To investigate how that protection worked, the researchers studied mice treated with cisplatin, a chemotherapy drug known to frequently cause neuropathy. Two doses of psilocybin — given nine days and two days before the first chemotherapy session, respectively — completely prevented the mice from developing hypersensitivity, and it also reduced cold sensitivity and preserved nerve endings in the skin.

The team then ran experiments using human sensory neurons and peripheral nerves that had been removed during surgery. These analyses pointed to a possible explanation: a process called mitochondrial trafficking.

Mitochondria generate the energy that cells need, but neurons present an unusual logistical challenge. Some peripheral nerves extend over enormous distances, so their mitochondria must be transported along structural tracks, called microtubules, to reach far-flung nerve endings. That in itself is an energy-intensive process.

Amit compared those microtubules to a railroad system: Chemotherapy can damage both the mitochondria themselves and the tracks they travel along.

In further experiments with human neurons, the team found that cisplatin depleted mitochondria and ATP (adenosine triphosphate) — cells' main energy currency — from the wires that extend from nerves. Psilocybin didn't restore the mitochondria's overall energy-producing capacity. Instead, it preserved their ability to travel and maintained their normal levels of ATP production, specifically within the nerve projections. That suggests the drug may help keep energy supplies where they're needed most.

The effect depended on the serotonin receptor 5-HT2A, which is responsible for many of psilocybin's psychedelic effects as well. Intriguingly, a compound called TBG — designed to activate 5-HT2A without causing hallucinations — also protected mice from neuropathy.

However, Amit cautioned that psilocybin's psychedelic effects may also be playing a neuroprotective role that we have yet to understand, so it's unclear if the effect should be avoided in humans.

A long way from patients

Strouse noted that mitochondrial damage in CIPN isn't a new idea. "What's novel is looking at psilocybin as a protectant," he said.

He also cautioned that different chemotherapy drugs may cause neuropathy through distinct mechanisms, so the protection demonstrated against one chemotherapy drug may not translate broadly.

Most importantly, the researchers have not shown that psilocybin prevents neuropathy in humans yet.

"The main thing is that it was never tested for this indication specifically in a systematic way in humans," Amit said. His team is now preparing a clinical trial at MD Anderson to test the approach. The research is part of MD Anderson's Cancer Neuroscience Program, a multidisciplinary effort that studies interactions between cancer and the nervous system, with an emphasis on improving patients' quality of life.

Human trials will need to establish both the effectiveness and safety of using psilocybin for this purpose, Strouse said, particularly before oncologists would consider giving a psychedelic drug alongside cancer treatment.

This article is for informational purposes only and is not meant to offer medical advice.

New Hubble observations have revealed a dramatic, 10-sided jet surrounding Saturn's south pole, and it appears to be evolving before our eyes.

The Hubble Space Telescope recently snapped a high-resolution view of the striking "atmospheric wave," which appears to have begun forming in 2023, archival Hubble images show. Scientists are curious about how this "decagon" popped up so quickly, given that Saturn's other famous multisided wave — a hexagon at the north pole — has been observed on the planet for 40-plus years.

"The question is, why did it suddenly form now when we haven't seen one before?" Amy Simon, a senior scientist at NASA's Goddard Space Flight Center and co-author of a new study describing the observations, said in a statement.

"The northern hexagon has been there every time we've looked for more than 40 years," Simon added. "This feature is different — it appears to be strengthening, giving us the rare opportunity to watch a giant atmospheric pattern develop."

Scientists can see the wave persisting through several atmospheric layers, which means it extends beyond the cloud tops. The wave is also found in a large jet stream at Saturn. More observations with Hubble and the James Webb Space Telescope (JWST) will be required to see how the wave is generated and what the decagon illustrates about atmospheres in large gas giants like Saturn.

The images were obtained as part of Hubble's Outer Planet Atmospheres Legacy program, which uses some of the telescope's time to image the solar system's outer planets — Jupiter, Saturn, Uranus and Neptune — once a year. The goal is to obtain long-term observations of these worlds, to supplement spacecraft orbiting or flying by.

From Earth's perspective, Saturn is slowly orbiting in its roughly 29-year journey of the sun so that its south pole is visible from our planet, allowing for a good view of the changing decagon. Hubble, in fact, was not the first to see signs of this decagonal shape; it was ground-based observatories that spotted a mysterious undulating band around Saturn’s south pole in 2024.

Agustín Sánchez-Lavega, first author of the study and a researcher in the Department of Applied Physics at the University of the Basque Country, and amateur astronomers Trevor Barry and Jean-Paul Oger first spotted the forming wave. The trio used the university's Planetary Virtual Observatory Laboratory, which brings in observations from around the world, to make the Saturnian discovery.

While more images in 2025 showed the wave starting to move into a decagon structure, Hubble was able to obtain high-resolution images without Earth's atmosphere in the way.

The Cassini spacecraft, which orbited Saturn between 2004 and 2017, didn't see the feature, hinting that it hadn’t started forming yet, according to NASA. "Given Saturn's symmetry in its north-south jet stream system, we have been searching for a counterpart to Saturn's northern hexagon on the south pole in Hubble images since 1990," Sánchez-Lavega said.

Both Hubble and JWST are expected to provide more opportunities to look at the ringed planet's developing decagon in the near future. In the meantime, Saturn isn’t the only solar system planet with perplexing polar features; 2017 images from NASA’s Juno spacecraft showed that Jupiter’s south pole is studded with gigantic, oval-shaped cyclones that echo the chaos of the planet’s famous Great Red Spot.

Archaeologists excavating in eastern Serbia have discovered the remains of a lavish and uniquely constructed Roman bath that once belonged to an emperor. The suite of rooms ‪—‬ which included heated floors, three bathing pools and a sauna ‪—‬ was uncovered at the bottom of a tower within an imperial palace, a design archaeologists had never seen before in the Roman Empire.

The bath complex, known in Latin as a balneum, was found at the archaeological site of Vrelo-Šarkamen, a monumental fortified residential complex that was built in the early fourth century and was occupied by Maximinus Daza (or Daia), who was Roman emperor from 310 to 313. Archaeologists have been excavating at Vrelo-Šarkamen on and off for decades, and the latest discovery was made by a research team from the Institute of Archaeology, an independent research institution in Serbia, according to a Sept. 3 statement.

Galerius Valerius Maximinus, born in what is now Serbia and originally named Daza, was one of the four Roman "tetrarchs." In A.D. 293, Emperor Diocletian essentially split the Roman Empire into two halves — Eastern and Western — and each was administered by a senior emperor and a junior ruler. By 305, the rulers of the Roman Empire were Constantius and Galerius as senior emperors and Severus and Maximinus Daza as junior rulers, but the tetrarchy had begun to fall apart. Maximinus claimed the title of senior emperor in 301 but lasted only three years. He died in 313 after losing a civil war against his rival, Licinius.

The new excavations at Maximinus Daza's imperial residence have revealed that the palace was even more complex and luxurious than previously thought, according to the statement.

Maximinus' palace had a monumental tower in the southwest corner. But archaeologists were surprised to find a circular bath complex on the lowest level of the tower, as most ancient balnea were oriented linearly, with rooms in a row. This bath area had a domed ceiling with six windows, which shows a high level of engineering knowledge, according to the statement.

The balneum was split into two sections: one for equipment needed to run the baths and one for bathing and relaxing. Within the equipment room, archaeologists found the furnace that heated the bath's floors. They also discovered the base for a copper boiler that would have been used to heat up bath water. However, the copper boiler itself is now missing.

Within the suite of rooms that the emperor used, archaeologists found three bathing pools or tubs, along with a sudatorium, the Latin word for a steam bath or sauna.

According to the statement, "the complex was not simply a space intended for personal hygiene, but a carefully designed private bath intended for high-status residents of the palace, in which architecture, technical infrastructure and comfort formed a single functional whole."

Researchers will continue to explore the bath complex to better understand how the rooms were structured and how Emperor Maximinus and his family accessed it.

From Augustus to Nero, see how much you know about ancient Rome's famous leaders with our Roman emperor quiz!

For the first time, physicists have measured the tiny quantum shift an object acquires by falling through Earth's gravity — an effect of Einstein's relativity that was predicted almost a century ago but never observed.

Researchers placed ultracold rubidium atoms into a superposition, a quantum state in which a single particle takes two paths at once. In this experiment, one path put the atom in free fall while the other kept it motionless. Recombining the atoms revealed an almost imperceptible difference between the two paths.

The measurement, published Sept. 2 in the journal Science Advances, shows that Einstein's equivalence principle — the idea at the heart of general relativity — still holds when it is pushed into the quantum world, creating a small but tantalizing link between relativity and quantum mechanics.

"The principle says that acceleration and gravity cannot be distinguished locally," Vlatko Vedral, a physicist at the University of Oxford and a co-author of the new study, told Live Science via email.

Einstein's happiest thought

The classic illustration of the equivalence principle is a thought experiment known as Einstein's elevator. A person sealed in a windowless elevator cannot tell whether the floor is pressing against their feet because the elevator is parked motionless on Earth or because it is being accelerated through empty space. Einstein called that realization the "happiest thought" of his life and built general relativity around it.

For heavy, everyday objects, the equivalence principle has been tested to extraordinary precision. Quantum objects are a different matter. They behave like waves, and each wave carries a quantity called phase — essentially, where its crests and troughs sit. Phase cannot be seen directly, but when two versions of the same particle are recombined, any mismatch between their phases shows up as an interference pattern. The two waves reinforce each other in some places and cancel each other out in others, thereby changing the odds of where the particle turns up.

Theory says that a wave in free fall should build up phase relative to an identical wave held still and that this phase should grow with the cube of the falling time. Therefore, doubling the fall time multiplies the effect eightfold. Charles Galton Darwin, a grandson of the famous naturalist, and Earle Kennard both documented this prediction in 1927 ‪—‬ but no one had measured it until now.

An atom that falls and stays still at once

Catching the effect required an instrument with one arm genuinely at rest with respect to Earth and the other in genuine free fall ‪—‬ something no previous experiment could supply. Matter-wave experiments going back to the neutron interferometry of the 1970s had measured gravity in other ways, but never with that pair of trajectories.

The team behind the new study, led by physicist Ron Folman at Ben-Gurion University of the Negev in Israel, chilled roughly 20,000 rubidium atoms into an exotic state of matter called a Bose-Einstein condensate, released them from their magnetic trap and ran the interferometer about 113 micrometers beneath an "atom chip" patterned with gold wires only 2 micrometers thick.

Radio and microwave pulses put each atom into a superposition of two magnetic states. A magnetic kick launched one of them upward, and a fraction of a millisecond later, a second pulse made that half insensitive to magnetic fields so that it rose and fell under gravity alone. The other half remained magnetically sensitive and felt a force tuned to cancel gravity exactly, leaving it suspended in place.

At the top of the arc, the two halves of a single atom stood about 7.5 micrometers apart ‪—‬ about seven times the width of the atomic wave itself — before the sequence was reversed to bring them back together. The team named the device the quantum Galileo interferometer, after the scientist who first argued that all objects fall at the same rate.

"Two different accelerations can be superposed, zero [acceleration] and the Earth's gravitational acceleration, and the resulting quantum interference measured," Vedral said.

A phase predicted almost 100 years ago

The researchers tracked the interference signal as they stretched the free-fall time to about 2.4 milliseconds. Across 633 runs over 5.3 hours, they recorded 13 complete oscillations, each one a full cycle of phase built up between the two halves of the atom. The growth followed the cube of the falling time, matching the theoretical model to within about 2.5%.

"The phase between the two elements of the superposition, which grows as the cube of the duration of the experiment and which was predicted a long time ago, in 1927, has now finally been observed for the first time," Vedral said.

The result matters because the same phase can be derived in two completely different ways: One treats gravity as a force acting on a quantum wave; the other moves into the falling frame, where gravity vanishes, and invokes the equivalence principle. Both give the same answer, and that agreement is what allows quantum mechanics and general relativity to coexist.

"They tell us that, at this level of accuracy, there is no conflict between quantum physics and gravity," Vedral said. "In other words, the equivalence principle is perfectly compliant with quantum mechanics."

The difficulty of bringing the two halves back together

The hardest part of the experiment was the recombination. Because the two halves of the atom end up moving at very different speeds, returning them to overlap in both position and motion is extremely demanding. Physicists Marlan Scully, Berthold-Georg Englert and Julian Schwinger named the problem the "Humpty-Dumpty effect." The magnetic fields also curve across the atom cloud, distorting the two halves in different ways.

The contrast of the interference fringes started at 80% for short runs and faded to 20% for the longest run, setting a practical ceiling on how long the experiment can run. The authors also cautioned that their measurement does not rule out every theory in which the equivalence principle breaks down, because some of those theories predict the same phase.

What comes next

The team now wants to test the equivalence principle under more general conditions, such as the "same experiment in a rotating frame," Vedral said. "Even more interestingly, performing an experiment in which two such systems are superposed and can gravitationally affect one another" would further test the results, he added.

That last idea points toward one of the field's central open questions. Scaling up the technique from atoms to far heavier objects, such as nanodiamonds, would let physicists ask whether gravity itself follows quantum rules and would open a route to testing the conjecture — championed by study co-author and Nobel laureate Roger Penrose — that gravity is what destroys quantum superpositions in the first place.

See how much you know about Albert Einstein with our Albert Einstein quiz!

With only a couple of months to go before the harvest season for winter wheat in Colorado, the crop faced a whiplash: After a warm, dry winter, a cold snap plunged the plants into freezing weather for 12 hours, and temperatures soared to nearly 90 degrees Fahrenheit (32.2 degrees Celsius) two days later. When the final harvest numbers were tallied in July, 73% of the crops were in poor or very poor condition. According to early estimates by Colorado Wheat, 2026's winter wheat crop was the smallest in the state since 1965.

Pick a crop, any crop, and you'll hear a similar story: Extreme weather and climate change are rocking the food supply. The warming climate makes food less nutritious, threatens crop survival, and triggers tipping points that would upend farming as we know it.

The impacts will be felt most intensely in less-developed regions of the world, where many people can't afford imported food and climate-related famines and nutritional scarcity are already happening.

But the U.S. is facing big changes to its food systems too, and no one is immune. Humans have overcome looming agricultural disasters before, but experts say the challenge should not be underestimated.

"There are real food security and nutrition concerns," said Andrew Hultgren, an environmental economist at the University of Illinois, Urbana-Champaign, "especially under these high-warming futures."

Food is becoming less nutritious

As the planet warms, food crops are expected to become less nutritious. That's because, due to plant biology that's not yet fully understood, crops grown under higher levels of carbon dioxide are deficient in zinc, protein, magnesium, iron and other micronutrients. Crops are already less nutritious than they were in the 1950s, but this is partly due to breeding decisions that prioritize yield over nutrition. The carbon dioxide deficiencies will exacerbate this nutrition decline.

The global monthly average concentration of carbon dioxide in the atmosphere is now over 420 parts per million (ppm), well over the preindustrial average of 280 ppm. By the end of the century, those levels will increase to at least 550 ppm in all but the most optimistic scenarios.

That will mean an additional 175 million people will be zinc deficient and an additional 122 million people will be protein deficient by 2050, a 2018 study found. Zinc deficiency has consequences for immune and skin health and may lead to poor growth in childhood; protein deficiency can also cause stunted growth as well as fatigue, muscle weakness and stress fractures. Those figures account only for the effects of carbon dioxide. A cascade of climate shifts and extreme weather may also affect the number of nutrients (and calories) available to the world.

The threats are myriad: Rising sea levels may inundate farmland and lead to saltier soil in coastal regions where, for example, rice farming is common. Soil salinity can make it impossible to grow crops in some regions. Droughts, heat waves, storms or temperature swings like those seen in Colorado this year might take out certain crops in particular places, leading to year-by-year price spikes or shortages. In the U.S., the results might look a lot like the recent egg shortages triggered by bird flu; temporarily empty shelves, price spikes, or even restrictions on the amount a customer can purchase in a visit for an affected food.

Climate shifts that harm pollinators and fuel the spread and introduction of plant pathogens such as harmful fungi will also likely reduce crop yields.

Areas that depend on the ocean for food are also facing steep challenges, due to both ocean acidification and the degradation of coral reef ecosystems, which are sources of food for many coastal communities and form much of the base of food chains for the larger fish people eat.

Hotter weather also affects food safety, said Christopher Golden, a professor of nutrition and public health at the Harvard T.H. Chan School of Public Health.

"Increasing sea temperature and increasing sedimentation within seas could lead to harmful algal blooms or increasing food poisoning events from temperature-related food spoilage," Golden said. Algal blooms can contaminate shellfish like oysters or scallops with neurotoxins that can sicken and kill people who eat them. Food spoilage is a concern in regions such as Madagascar, where catches are brought ashore and readied for consumption in the open air.

Meanwhile, fish may move poleward to avoid the hottest sea temperatures, leaving the most vulnerable regions ‪—‬ such as Southeast Asia, the Caribbean, Africa, Central America and the Pacific ‪—‬ with fewer fish in their waters. How bad this looks depends on the extent of the climate swings, with research suggesting that without any mitigation, fishers could see their catches decline by 58% to 92% off small islands in the Pacific and by 70% to 86% in Southeast Asia. This would drive food insecurity and malnutrition in those regions. The U.S. will likely face impacts too, as most of its seafood is imported from subtropical or tropical waters elsewhere.

There may be shifts in trade networks that lessen the blow for U.S. consumers, Golden said, but it's hard to predict. Some possibilities include "price shifts or trade shifts that lead to changing dietary patterns or more shelf-stable and heavily processed items that we know aren't good for your health," he said. In other words, less fresh-caught snapper and more potted meats.

Changing foods on the table

Individual producers are adapting, sometimes in ways that may not be immediately obvious to consumers. "Climate change is bad in that it's a slow-moving wave," said Elizabeth Wolkovich, a professor of forestry at the University of British Columbia. "You don't really notice that it's shifting underneath you and that the apple you eat isn't the apple your granddaughter will eat."

On that note, growers in the Pacific Northwest and U.S. Northeast will face challenges getting apples to lunch boxes around the world. Fewer cold days and more extreme-heat days will likely reduce apple yields by affecting how and when trees go dormant and bloom. Because it takes five or more years to establish fruiting trees in new regions, this could mean a reduced apple supply and higher prices.

Today's smooth arabica coffee (Coffea arabica) varieties may get harder to find and more expensive as climate change forces coffee growers out of many of the places they used to farm and droughts reduce supply. Earthier, more bitter robusta coffee beans (Coffea canephora) do better in warming temperatures, but even those beans could struggle with increasing seasonal variability caused by climate change.

Climate has already shifted wines in favor of less-acidic and higher-alcohol varieties, Wolkovich said, but it's happened slowly enough that, unless you're a connoisseur, you may not have noticed. Wine lovers can expect more changes: Wolkovich has found that the varieties of wine grapes that growers can produce will shift with climate change. Wildfires in grape-growing regions like California can also produce an unpleasant acrid and smoky flavor in wine.

And it's not just flavors that will be affected. U.S. dairy cattle breeds originated in cool and cloudy Northern Europe, and their milk output goes down as temperatures climb. Such heat stress reduced annual milk yield by an average of 1% a year between 2012 and 2016 alone, and heat-related losses are expected to balloon by 30% by 2050.

Americans have long been drinking less milk from the glass, but their demand for yogurt and cheese is rising, said Jared Hutchins, an assistant professor of agricultural and consumer economics at the University of Illinois Urbana-Champaign and first author of the study on milk yield. Those products depend heavily on the fat and protein content in milk, which is the first thing to drop when cattle are hot. "Fat and protein are what deliver the cultured dairy products that are in high demand," Hutchins told Live Science.

The story repeats itself across agricultural products, Hultgren said. "For each degree of that global temperature rise, caloric output [from crops] drops by 120 kilocalories or U.S. calories per person per day," he said, "which is about 4.5% of a person's daily recommended caloric intake."

That calculation, published by Hultgren and his colleagues in the journal Nature in 2025, already accounted for adaptations that farmers can make to reduce crop losses. Without those adaptations, the number would be over 30% higher, he said.

Reductions in available calories will translate to food shortages in vulnerable places, such as the Horn of Africa or India, said Marina Romanello, executive director of a multinational research project that tracks the impacts of climate on health at University College London. In North America, "it would feel like inflation," Hultgren said ‪—‬ yet another factor driving up grocery prices.

Worst-case scenarios

For farmers, the year-by-year uncertainty of climate change is a problem. Will this year bring drought? Will there be a sudden storm or flood that will wash away the spring crop? Should they take a risk on a new heat-resistant plant or agricultural technique?

Similar uncertainty haunts the long-term forecast. Climate tipping points can lead to sudden, irreversible changes in the system. For agriculture, one of the scariest tipping points is the potential collapse of the Atlantic Meridional Overturning Circulation (AMOC). This pattern of ocean currents brings warm surface water north from the equator and circulates cold water south, warming Northern Europe and the northern parts of North America and cooling the Southern Hemisphere.

If this current were to collapse, northwestern Europe would cool dramatically, with studies suggesting that London could see temperature lows of minus 4 F (minus 20 C) ‪— ‬colder than the city's lowest temperatures on record. Precipitation would decline across Europe, leading to drought. Meanwhile, in the Amazon, the wet season could become the dry season and vice versa, said René van Westen, a climate researcher at Utrecht University in the Netherlands who has studied the impacts of an AMOC collapse.

On the other hand, if the AMOC doesn't collapse, London is expected to warm by 4.9 F (2.7 C) and see 15% to 18% more precipitation, depending on the season. The uncertainty in these predictions makes preparations difficult. There is still a lot of controversy over whether the AMOC will collapse and, if so, when. Should farmers plan for England to become increasingly toasty, or should they expect it to be plunged into a little ice age?

AMOC-related changes will take decades to centuries to unfold, even with a total collapse, van Westen told Live Science. But even so, they would require a total rewriting of agriculture in Europe and the northeastern U.S. "It will be very challenging to adapt to such a scenario," he said.

That doesn't mean a collapse of the world food system is inevitable. Farmers are already adapting to the early impacts of climate change by scaling back water-hungry crops in drought years and, in some places, testing new, heat-resistant varieties of crops in an attempt to stem the losses.

And humans have overcome looming disaster in agriculture before: In the 1950s and 1960s, new varieties of rice and wheat, along with the availability of synthetic nitrogen fertilizers, spurred the "Green Revolution," tripling the world's yield of cereal crops while expanding farmland by only 30%. Similar innovations could limit hunger even as the world warms.

But the biggest way to mitigate these impacts is the most obvious one. While Hultgren and his colleagues found that adaptation could cut caloric losses under climate change by 30%, mitigating warming by reducing emissions today could slash them by half. Similarly, the AMOC is on a path toward weakening, van Westen said, but as long as humans slow the pace of climate change, the current can recover.

"If you are cutting your emissions," van Westen said, "you can lower your risk."

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A fruit fly's brain is roughly the size of a poppy seed — and yet that tiny package contains over 100,000 neurons. A new map charts every single neuron in the male fruit fly brain, as well as the insect's equivalent of a spinal cord, totaling more than 166,000 neurons.

This new map joins a map of a female fruit fly brain that was unveiled in 2024 and covers about 140,000 neurons. These two wiring diagrams, also called "connectomes," can now be compared to see if there are differences between the sexes' brains that help to explain behavioral differences reflected during mating or in aggressive actions, including sex-specific fighting moves.

"It is the first time we can compare both sexes of an animal with complex social behavior," study co-author Gerry Rubin, head of biology and a senior group leader of the Howard Hughes Medical Institute's Janelia Research Campus, said in a statement. "Male and female flies have a lot of differences in their behavior, and neuroscientists want to understand how the brain controls those behaviors. This now allows us to easily home in on the neurons that are causing those differences."

Initially released as a preprint, the new fly brain map was published in the journal Cell and Current Biology Thursday (Sept. 3). The study describing the map was published alongside three other papers, each of which uses the new data to explore a specific aspect of fruit fly neurobiology.

"The fly nervous system performs remarkably sophisticated computations with relatively few neurons and little energy, and its architecture could suggest principles for designing more efficient artificial systems," said Carlos Ribeiro, a principal investigator at the Champalimaud Foundation in Lisbon, Portugal, whose team contributed to the brain map and led one of the related studies.

"This work also provides a technical roadmap for more ambitious connectomics projects in the future, such as those for mice and humans," Ribeiro said in a separate statement from the Champalimaud Foundation.

In the near term, the scientists aim to map the brains of larval zebrafish (Danio rerio) and adult danionin fish (Danionella). In the long run, the goal of this research is to understand how vertebrates' brains enable complex behaviors, and then use that knowledge to help unravel the basis of neurological and psychiatric disorders in humans.

The study led by Ribeiro and other Champalimaud Foundation scientists aimed to map the circuits in the fly brain dedicated to the insect's sense of taste. Fruit flies have taste receptors in many body parts, including their legs, wings, mouthparts and inside of the throat. The researchers identified these taste receptors and traced their connections back to the fly brain. From there, they examined how those circuits interacted with those that govern behaviors such as swallowing or walking. When it comes to eating behaviors, this circuitry helps the fly determine whether a given morsel is safe or harmful and ultimately choose whether to eat it, the researchers concluded.

This diagram of taste processing is a "hypothesis-generation tool," study co-author Inês de Haan Vicente, a research technician in Ribeiro's lab, said in the Champalimaud statement. "Suppose you are interested in how taste controls locomotion. Now you can go to the map and ask: which sensory neurons are connected to the neurons controlling locomotion? Which intermediate neurons should I manipulate? It gives you a place to start."

The other two papers published alongside the map respectively explore the circuits behind vision processing in the fly brain and sex-specific differences in male and female fly brains. The first showed that visual processing extends deep into the brain, involving more than half of the 11,000 or so types of neurons identified in the map. The latter study found a network of cells that's specific to the male brain and appears to coordinate male-specific behaviors, such as specific aspects of fly courtship and physical aggression. (For example, female flies tend to headbutt while males lunge at their targets.)

While there were some networks specific to each sex, the circuits for sensation and movement are largely shared between males and females, the research found. At times, specific switches within those circuits reroute signals to different destinations in the male and female brain; the consequences of that rerouting will be a focus of future investigations.

See how much you know about the most complex organ in the human body with our brain quiz!

Scientists have identified an ancient volcano on England's east coast that is so eroded, it took researchers three decades to piece together its enormous size and explosive past. What remains of the caldera system is located beneath the English counties of Norfolk and Lincolnshire.

However, while the volcano undoubtedly produced at least one huge-scale eruption, some experts don't think there is enough evidence for the structure to be called a supervolcano.

"It obviously must have been a very large eruption, but it would be very difficult to calculate the volume of the eruption given the poor preservation of the deposits," said Michael Poland, a research geophysicist with the Cascades Volcano Observatory and the scientist-in-charge of the Yellowstone Volcano Observatory. "This is part of the reason I really hate the term 'supervolcano,'" Poland, who was not involved in the discovery, told Live Science in an email.

In a recent analysis, published April 29 in the Geological Society of America Bulletin, scientists examined zircon crystals that were taken 80 years ago from boreholes 40 miles (65 kilometers) apart in Norfolk and Lincolnshire. Zircon crystals are smaller than the diameter of a human hair and form within molten magma underground before a volcano erupts. They contain uranium that decays into lead isotopes at a known rate, enabling researchers to precisely date eruptions.

The results showed an age match between the zircon crystals from Norfolk and Lincolnshire and counterparts taken from the Kinnekulle tephra, a thick layer of volcanic ash covering Scandinavia and the Baltic region. This suggests the ash plume from the volcano in what is now eastern England blew across the Tornquist Sea, a body of water that existed during the Ordovician period (488.3 million to 443.7 million years ago), and settled on what is now Scandinavia.

Researchers already knew that the Kinnekulle tephra was formed during a massive volcanic eruption. But the recent analysis shows for the first time how far the ash traveled and, therefore, how big the eruption really was.

The eruption would have also produced huge pyroclastic flows, or avalanches of rocky debris, ash and hot gas that race down the sides of some erupting volcanoes, said Peter Rowley, a volcanologist and senior lecturer at the University of Bristol in the U.K. who was not involved in the analysis. "The last eruption of this kind of scale was the Oranui event at Taupō in New Zealand, over 26,000 years ago," he told Live Science in an email.

However, while the explosion would have been impressive and equivalent to the force of thousands of atomic bombs, experts said the definition of a supervolcano is vague and there are better ways to describe what happened.

"The scientific definition of a supervolcano varies a little; it’s a term we tend not to use as volcanologists much," Rowley said. "In this case we would describe it as an ultraplinian eruption."

Ultraplinian eruptions are the most violent type of volcanic explosions, ejecting more than 240 cubic miles (1,000 cubic kilometers) of material. It's difficult to say exactly what the eruption that formed the Kinnekulle tephra would have looked like, but it likely lasted days to weeks and formed ash clouds taller than 25 miles (40 km) that reached into the stratosphere.

Geologists tend to reject the term supervolcano because it is imprecise, instead preferring to describe eruptions by the volume of material they eject.

Stephen Self, a physical volcanologist at the University of California, Berkeley, agreed that the term supervolcano can be too vague. "Supervolcano has become a kind-of buzz-word," he told Live Science in an email. "It's the deposits of the eruptions that are recognized, not the volcano."

Very little of the material ejected in England's ultraplinian eruption remains today, because most of it was eroded or buried. "The geological record is far from complete so it can be very difficult to say much about these eruption volumes with very old volcanoes," Rowley said.

Similarly, the Kinnekulle tephra has been degraded over time, Poland said.

The analysis also found evidence for an earlier eruption of the volcano that occurred 453.7 million years ago. However, there is no trace of these eruptions at the surface today; the boreholes are located in some of England's flattest landscapes, study first author Tim Pharaoh, a geophysicist with the British Geological Survey, said in a statement in August.

It's not surprising to find traces of big, ancient volcanoes in England. The recently identified volcano is part of a wider volcanic system that was active 450 million years ago and includes Eryri National Park in Wales and the Lake District in northwestern England, Rowley said.

"It's best not to imagine whole preserved volcanoes, but rather that we have deposits from their eruptions, or rocks which formed in the magma reservoirs beneath the original volcano," Rowley said. "These are often deformed and altered by tectonic events meaning that it takes some careful geological investigation to interpret the true picture."

China's solar power capacity has overtaken coal for the first time, marking a major milestone in the country's rapid expansion of renewable energy.

China had about 1,288 gigawatts (GW) of installed solar capacity at the end of July, compared with 1,285 GW of coal-fired capacity, according to figures from the country's energy administration reported by the South China Morning Post.

The milestone could have major implications for global efforts to tackle climate change: China is the world's largest annual greenhouse gas emitter, accounting for around 30% of global planet-warming emissions. If its rapid expansion of renewable energy begins to displace coal-fired power ‪—‬ one of the country's primary sources of greenhouse gas emissions ‪—‬ the impact could extend well beyond Chinese borders.

"China reaching around 1,288 GW of installed solar capacity, marginally overtaking coal, is a major milestone," Matthew Davies, UNESCO chair in sustainable energy technologies and a professor of chemical engineering at Swansea University in the U.K., told Live Science.

However, installed capacity doesn't necessarily equate to actual electricity generation. "Solar only generates when sunlight is available, whereas coal plants can run for much longer periods, so solar still supplies a much smaller share of China's electricity than coal," Davies said.

In other words, China has more solar capacity than coal capacity, but coal remains far more important when it comes to the amount of electricity actually delivered to the grid.

Between January and July this year, Chinese solar power output rose 15.5% compared to the same time period in 2025. Over those seven months, it reached 802.4 TWh, which is around 13% of the country's total electricity consumption.

"I would see this as a structural turning point, not the point at which solar has replaced coal," Davies said. "The key question is whether renewable generation can grow fast enough not only to meet rising electricity demand but to push coal generation down in absolute terms. Given the scale of China's power system, sustained reductions in coal use could have a major impact on global CO₂ emissions."

To do that, China will need to do more than build solar farms. One of the biggest challenges will be integrating all of the new renewable power into the electricity system.

"Installing solar is only part of the transition; grids, transmission, storage and demand flexibility all need to keep pace so that renewable electricity can actually be used," Davies said.

This transition toward solar panels will also make renewable energy more accessible around the world, as China's enormous manufacturing capacity will help drive down the global cost of solar panels. However, Davies said the next phase of the transition is to ensure the whole solar production process is sustainable. "We need to think about where technologies are made, where materials come from, how long they last, and how they are reused or recycled," he said.

Solar panel manufacturing involves raw material extraction, processing, manufacture, transport and installation, so it has an initial carbon footprint. High energy requirement for polysilicon production is a considerable factor as it uses coal-fired power plants. But, this is offset by the electricity they generate.

There is also a case for expanding local and regional manufacturing, Davies noted. Doing so could strengthen supply chains, create local skills and economic value, and make the global energy transition more resilient and equitable. That could be particularly important for expanding access to electricity in parts of the world where reliable power remains limited.

"The global energy transition is not only about replacing fossil fuels in existing electricity systems; it is also about enabling people who still lack reliable electricity to gain access to clean, affordable power," Davies said. "Ultimately, success is not simply about installing more solar panels. It is about building a clean-energy system that is affordable, sustainable, resilient and accessible globally."

Archaeologists in Bulgaria have discovered a human skeleton inside a giant Roman jar. It's likely that the individual sought shelter in the vessel during an enemy attack over 1,600 years ago but died as a fire swept through the area.

The team unearthed the gigantic jar in a Late Roman turret, or small tower, in the Roman colony of Deultum on Aug. 10. It's unclear which battle led to the individual's death, but Deultum faced many attacks from East Germanic tribes and Huns in the fourth and fifth centuries, lead excavator Lyudmil Vagalinski, an archaeologist at the Bulgarian Academy of Sciences, told Live Science in an email.

The individual's remains were found with two iron knives and a belt inside the container, a type of jar known as a dolium. These huge vessels were the largest type of pottery in antiquity (from roughly the eighth century B.C. to the fifth century A.D.) and were used to store goods such as olive oil and wine. The largest dolia could hold more than 260 gallons (1,000 liters), although the surviving lower part of the newfound dolium was smaller, measuring approximately 3 feet (1 meter) in diameter, Vagalinski said.

Even though Vagalinski and his colleagues had been excavating the turret, which is the northern turret of Deultum's western Roman gate, they weren't expecting to find human remains there, according to Standart News, the Bulgarian outlet that first covered the finding.

"We were surprised," Vagalinski said in an email. It's very rare for archaeologists to discover human remains inside the cities of antiquity except in the case of "extraordinary circumstances" ‪—‬ like earthquakes, enemy attacks or volcanic eruptions, he said. Even in these cases, survivors would search for their dead to bury them beyond the city walls, but they often didn't know that there were dead bodies under the ruins.

The recent discovery seems to represent one of those "extraordinary circumstances," Vagalinski said. The team found a significant amount of burned materials around the dolium, including ashes and coals; broken bricks, tiles and shards; blackened walls; melted glass fragments; and bones from domestic animals. The likely scenario is that, upon hearing of an imminent attack, people brought their livestock into the fortress. The archaeologists also found many bronze coins that were probably lost in the chaos.

The individual, presumably a young man, was likely part of this tumult and climbed into the dolium to hide or seek shelter, Vagalinski said. And while it's unknown how the fire started, the presence of ashes under the skeleton in the dolium indicates that the individual went inside after the fire had already begun, Vagalinski said.

The team's preliminary analysis dates the event to approximately A.D. 400, though they'll have a more precise date after they process the rest of their field data, according to Vagalinski.

The young man was likely hiding from the raging fire in the empty dolium and held an iron knife between his legs to defend himself in case the attackers found him, Vagalinski explained. He had a second knife in his belt.

"In any case, he made no attempt to get out of the ceramic vessel," Vagalinski said. The team determined this based on the individual’s position, similar to that of a sleeping man. "After the attack, the inhabitants of the city leveled the ruins of the tower and covered them with a new, higher floor." They did not know that a fellow citizen was lying at the bottom of the dolium.

The skeletal remains have been moved to Sofia, the capital of Bulgaria, where they will be analyzed by a physical anthropologist, according to Vagalinski. Next summer, the team will head back to Deultum to try to unearth the entire western Late Roman gate, which dates to approximately A.D. 300. The researchers are "eager to reveal its whole plan and proper chronology," Vagalinski said. They also aim to complete the investigation of the gate's northern turret, where they found the dolium.

Earlier this year, the team discovered an older latrina, the Latin word for toilet, dating to between the second and third centuries, near the gate.

From Augustus to Nero, see how much you know about ancient Rome's famous leaders with our Roman emperor quiz!

The patient: A 47-year-old woman in Canada

The symptoms: The woman underwent a lung transplant to treat interstitial lung disease, which involves harmful inflammation and scarring of lung tissue. While recovering in the hospital, she ate a bowl of breakfast cereal, which activated a nearly two-hour episode of flushing, itching, shortness of breath and low blood pressure.

This severe, life-threatening allergic reaction is known as anaphylaxis. A report of the woman's case does not mention specific treatment she received for this reaction, but it notes that it resolved after two hours.

(Treatment for anaphylaxis involves epinephrine (also called adrenaline), and it can also require antihistamines, cortisone, oxygen and beta-agonists, such as albuterol, which help improve breathing.)

What happened next: The woman experienced the same symptoms in the weeks after being discharged from the hospital — after eating a coconut cream pie and after having an almond candy bar.

The diagnosis: Two months after her lung transplant, the woman underwent a skin-prick allergy test, which revealed a sensitivity to peanut and pine nut allergens. She did not have an allergic response to tree nuts, such as the almonds in the candy bar, nor to coconut. None of the foods that triggered her symptoms were known to contain peanuts, but none were certified as peanut-free, either.

Notably, the woman's lung donor had been a 12-year-old boy with a known peanut allergy but no history of anaphylaxis. Her doctors theorized that the transplanted lung tissue contained immune cells from the donor that were sensitized to nut allergens.

The treatment: The woman did not receive a specific treatment to get rid of this new allergic response. However, the sensitivity subsided in follow-up skin-prick tests, and they had disappeared completely by a year after her surgery. She ate peanuts in a supervised setting a few months after the one-year mark and had no reaction.

The doctors reasoned that the sensitized immune cells from the donor must have cleared from her body.

What makes the case unique: Only one other case of peanut allergy following a lung transplant had been documented before the woman's case was published in 2011.

Scientists had only recognized the risk of allergies being passed from organ donors to recipients a little over a decade before the report, according to a 2025 review of such instances. Doctors had previously reported allergy transfer linked to bone marrow transplants, which makes sense given that bone marrow produces immune cells. But the first known donor-acquired allergy from a solid-organ transplant was observed in 1997 following a combined kidney-liver transplant from a donor who was allergic to peanuts.

The authors of the 2025 review noted that donor-acquired allergies are more commonly associated with lung and liver transplants than with transplants of other solid organs. That could be because these organs are rich in a type of immune cell that produces allergen-specific antibodies, called B lymphocytes.

Other potential culprits for donor-acquired allergies are mast cells and basophils, two types of immune cell that bind to those allergen-specific antibodies. The cells hold onto the antibodies, and when they encounter an allergen, they release the inflammatory compounds responsible for anaphylaxis.

In the woman's case, a blood test for peanut-specific antibodies came back negative. This suggested that her body was not continually generating the antibodies. That could serve as possible evidence that her reaction was caused by antibodies bound to mast cells or basophils within the donor tissue, rather than antibodies produced by lymphocytes.

That said, the woman's reaction to the skin-prick test could imply that lymphocytes were still involved in the allergic reaction, the doctors added, as they did not know whether mast cells or basophils could migrate to the skin the way circulating antibodies could.

Regardless of the cell type behind the woman's peanut allergy, the sensitivity faded after a year, consistent with other cases described in the 2025 review. Still, the review authors called for better donor allergy labels to inform allergy testing and treatment for organ recipients. The doctors in the case report came to a similar conclusion, noting that detailed donor allergy histories and skin-prick testing after organ transplant could help identify donor-acquired allergies.

For more intriguing medical cases, check out our Diagnostic Dilemma archives.

This article is for informational purposes only and is not meant to offer medical advice.

A sunken World War II hospital ship off the coast of Albania has attracted both invasive devil firefish and rare Mediterranean monk seals, leading researchers to weigh the risks and benefits of these wrecks for local ecosystems.

The ship, called the Po, sank off Vlora Bay in 1941 after being hit by a torpedo from a British Fairey Swordfish aircraft during the Greco-Italian War, one of the conflicts within World War II. It is now acting as an artificial reef, with over 80% of its surface teeming with marine life, researchers reported July 27 in the journal Frontiers in Ocean Sustainability.

This phenomenon, by which submerged structures attract marine life, is called the artificial reef effect, and it occurs when marine life colonizes a newly introduced solid structure underwater. These structures can provide shelter because crevices and dens serve as hiding places, as well as food from the algae and other organisms that grow on its surface.

While there has been research on Vlora Bay generally, there was no historical biological or quantitative data for the Po wreck itself. The new study sought to find out more about how the ship's structure affected the surrounding seabed and how marine organisms have colonized it.

Devil firefish (Pterois miles) are native to warm coastal waters and coral reefs of the West Indian Ocean and the Red Sea. However, the new study found these fish swimming around the shipwreck off the coast of Albania, around 800 miles (1,300 kilometres) away, between June 2022 and September 2024, with up to seven individuals observed simultaneously. The study authors suggested that shipwrecks like Po could be attracting these invasive animals from their natural habitat toward more temperate waters.

“Unfortunately, I can't call it a true scientific surprise, because the effects of climate change are now sadly well known and predictable," Simone Modugno, a biologist and scientific diver at the University of Ferrara in Italy and co-author of the study, told Live Science. "What's perhaps most surprising is the speed with which these climate changes are occurring, acting as a driver and amplifier for the incursions of tropical and alien organisms. I'm talking about impressive salinity and abnormally high temperatures, with persistent peaks of extreme heat."

The researchers noted that the presence of these fish is part of a wider problem: More invasive species are migrating from the Red Sea through the Suez Canal and into the Adriatic Sea due to warming global temperatures. Modugno said she expects a "serious problem" involving the devil firefish within the next 10 years.

"For at least three years, I've observed a steady and unstoppable increase in fish such as Pterois miles along the Albanian coast, as well as other invasive plant species, mollusks, and shellfish, as well as the spontaneous return of the Mediterranean monk seal," Modugno said. "Now, the Albanian coasts are experiencing constant overgrazing, just like the Greek and sub-Italian coasts, and the lionfish population is literally exploding.”

The study confirmed that this was one of the northernmost reported occurrences of the firefish in the Adriatic Sea.

However, invasive species aren't the only ones attracted to these shipwrecks. The researchers also noted 28 fish species living around the wreck, egg clusters belonging to the Ommastrephidae family of squid, and even sightings of the rare Mediterranean monk seal (Monachus monachus).

Most notably, researchers captured a monk seal resting within the sheltered cavities of the wreck in August 2023, which was the first confirmed sighting of the species in Vlora Bay since 1996.

This monk seal species typically breeds in sheltered sea caves across Mediterranean beaches. However, tourism and other human activities have forced the species into more isolated and dangerous caves. This, along with other threats from fishing entanglement, continue to threaten the seals. The sighting indicates that monk seals are using these artificial reefs as potential resting opportunities when their natural habitats are fragmented, the researchers said in the study.

A massive volcano erupts in Southeast Asia. Ash fall delays flights and destroys crops, while pyroclastic flows wipe out entire towns. Over the following weeks, the sulfur dioxide pumped out turns into a haze of fine acid droplets, eventually wrapping around the entire planet, scattering sunlight back to space. The sun turns pale, shadows go soft, the sky glows violet after sunset and the ground below cools. The next summer never appears. Harvests fail from the American Midwest to the monsoon belt in Asia. Countries close their borders, and people who have never heard of the volcano begin to starve.

This nightmare scenario has yet to happen, but it's not a matter of if but when a world-changing event like this will hit, and governments need to start preparing for global catastrophes that could disrupt the food system on an unprecedented scale.

There are three main steps we need to take soon: put events like nuclear war, a huge volcanic eruption and a continent-wide blackout into national risk assessments; agree to trade rules for such an emergency before it arrives; and fund pilot projects now for foods so we know what can be produced at scale without much sunlight or without fertilizer.

We've been faced with turbulent times the last few years with COVID, the Russian invasion of Ukraine and the Iran war. And the current outlook indicates there's more trouble ahead — the closure of the Strait of Hormuz alone could disrupt global food production, for example. A significant part of the world's traded fertilizer passes through it, and the United Nations Food and Agriculture Organization has warned that the shortfall will cut yields into 2027.

This shows that in today’s interconnected world, regional crises will influence countries far away from it. With larger catastrophes, these ripple effects in the global system would be more widespread, quicker to take hold and on a higher magnitude.

Critics might question why we need to prepare for such Black Swan events. But global catastrophes are not as unlikely as they feel. Ice cores enable us to count large eruptions of the past. On that basis, volcanologists put the chance of a magnitude 7 eruption — the size of Tambora in 1815, which caused a "year without summer" — at roughly 1 in 6 this century. Estimates for a repeat of the 1859 Carrington solar storm, which could disrupt power grids on a continental scale, run from about 1% to 12% per decade. Nuclear-armed states are almost constantly engaged in conflicts, risking nuclear war.

Each of these events might seem unlikely. But in combination, they add up to a significant chance that at least one of them will happen this century.

What they all have in common is that they all would drastically impact the food system. A volcanic eruption, the firestorms of a nuclear war or a large asteroid impact all push particles into the upper atmosphere that block sunlight, which would lead to colder, drier growing seasons that could result in harvest losses up to total failure. In the most extreme nuclear war scenario, researchers estimate that global calorie production could drop by around 90%. A long blackout, caused by a powerful solar storm for example, works differently but has the same consequence: no fertilizer, no pesticides, no fuel, and the sharpest yield losses exactly where we produce most food today.

Hardly anyone is assessing these risks. Even the countries doing it best fall short. The U.K. and Switzerland are good examples. The U.K. National Risk Register lists 89 risks, including volcanic eruptions, severe space weather, pandemics and a nuclear miscalculation abroad. However, the catastrophic events it considers are all relatively small-scale — with a "reasonable" worst-case scenario of over 1,000 deaths and a cost of tens of billions of pounds — and the register does not even begin to consider events like a global famine or a nuclear war that could lead to tens of millions of deaths and cost trillions of pounds.

Switzerland's national risk analysis, meanwhile, covers 44 hazards including a solar storm, a foreign volcanic eruption and a meteor strike. Again, the scale is too small. The volcano is a moderate European eruption and the meteor is 66 feet (20 meters) across, comparable to the Chelyabinsk impact in 2013. Many other countries do not even consider risk on these limited scales.

No country can solve this alone. In a review, my colleagues and I highlighted the key factors that would make countries and communities more resilient to various global catastrophes. These include food self-sufficiency, decentralization, geographic isolation and governance quality — meaning working institutions, low corruption and low inequality. Australia scores best, but even Australia would struggle without imported fuel, medicine and fertilizer. Nowhere is a refuge on its own.

Countries will need international collaboration to make it through a crisis of this scale. Export bans have been a common reflex in food crises of the past. After a global catastrophe, they would only isolate countries from each other and lead to further damage, as export bans can easily lead to the situation where enough food is still around, but nobody is trading it and so people starve.

We need to work on rules to govern trade under those circumstances before a global emergency occurs.

You might say the probabilities are too small to justify the cost, and that money spent on hypothetical volcanoes is money not spent on floods, hospitals and defense. This criticism might land if you only look at a single catastrophe. However, there is a whole portfolio of events that could lead to global catastrophe. In combination, there is a good chance that one of them will hit, and if it does, we better be prepared. Also, many of the preparations needed are not even that expensive. Low-input farming, decentralized grids, a diverse food supply and more exhaustive risk assessment are within grasp of most countries.

This needs to happen now. Starting work on resilient foods or better international agreements when a global catastrophe has already occurred is too late. You cannot start an industry in the month the harvest fails. Clearly, prevention is better than resilience, but some of these events cannot be prevented at all. When one of them arrives, the difference between the societies that prepared and those that did not will be measured in lives.

Opinion on Live Science gives you insight on the most important issues in science that affect you and the world around you today, written by experts and leading scientists in their field.

While building a terrace in their backyard, a homeowner in Denmark discovered the treasure of a lifetime: more than 40 pounds (18.5 kilograms) of thousand-year-old silver buried in the ground. An analysis revealed that the finding is the country's largest Viking Age (793 to 1066) silver hoard known to researchers.

The hoard has approximately 700 silver objects, including silver bars, jewelry, 47 whole coins and coin fragments, and a small Thor's hammer, an object that was often interpreted as a sign of protection and a clue that its owner believed in the Norse pantheon of gods. About 320 of those objects were contained in a clay vessel, while the rest lay in the soil nearby. The treasure is nearly three times larger than the previous largest silver hoard from Denmark's Viking Age, according to a translated statement.

One of the silver bars is engraved with runes, a writing system used by people in Scandinavia during the Viking Age. The inscription might say "hutu," which may represent a person's name or an owner's mark, according to the statement.

The anonymous individual found the roughly 1,100-year-old hoard while building a terrace in the municipality of Rebild this past spring. Unexpectedly, they hit something that emitted a strange sound. "It should have just been a few hours of hard gardening work removing stubborn grass, stones and gravel for a new tiled terrace, but it turned out to be the biggest surprise of my life," they said in the statement.

The coins include two Anglo-Saxon silver pennies minted during the reign of King Edward the Elder (ruled from 899 to 924), according to the statement. This suggests that the hoard dates to sometime in the 10th century.

There are also Islamic coins in the hoard, and together with the Anglo-Saxon coins, they offer evidence that Viking Age Denmark had strong connections with vast regions of Europe as well as with distant eastern regions, according to Torben Sarauw, cultural heritage manager at the North Jutland Museums. There is already ample evidence of the Islamic world's connections with Scandinavians during the Viking Age, including a recent discovery that Viking pennies in a hoard found in Denmark were made from melted Islamic money.

The newfound hoard sheds light on how people in Viking Age Denmark could store, organize and hide their wealth. "When we analyze the weight of the silver objects, the treasure reveals information about the economic practices of the Viking Age," Sarauw said. "The treasure does not only consist of beautiful objects. Most of them are part of a structured value system by weight."

In fact, all the silver bars and some of the bracelets and silver fragments can be organized into specific weight groups. This indicates that the collection represented an important storage of wealth and not a random assortment.

"The treasure so clearly shows how silver functioned as wealth and a means of payment in the Viking Age," Sarauw added in the statement. "It's like finding a safe from the Viking Age."

It's unclear why the hoard was buried. It may have been hidden close to a Viking settlement, along a now-bygone road, or placed in a more remote, secret location, according to the statement. Answering that question would require major archaeological investigations, which are impossible in the developed area where the hoard was discovered.

The hoard is now being submitted for assessment at the National Museum of Denmark.

See how much you know about ancient norsemen with our Viking quiz!

Football is a high-impact sport. A player may take hundreds of hits over the course of their career, including some that cause concussions. Other impacts may seem minor at the time, but there are concerns that repeated head blows can negatively impact long-term brain health.

Those worries gained new attention after a recent study estimated that at least 25% of recently deceased NFL players had chronic traumatic encephalopathy (CTE). CTE is a degenerative brain disease linked to repeated head impacts. Although the study doesn't necessarily mean that 25% of current NFL players have CTE, it does add to the growing evidence that repeated hits may carry serious consequences.

The NFL has taken steps to reduce those risks, including strengthening concussion protocols and investing in safer equipment, like Guardian Caps. But are those measures enough? With new research continuing to shed light on CTE, we want to know what you think. Weigh in via our poll below, and let us know your thoughts in the comments.

A man searching for spare auto parts at a junkyard in Poland discovered an entirely different kind of treasure: part of a 1,800-year-old shield that was filled with bones.

The shield's age and location suggest that it belonged to a Vandal warrior, according to the archaeologists who excavated the find. The Vandals were Germanic people who lived in Poland at that time. After the Germanic invasions of the Roman Empire, the Vandals, whose name became synonymous with destruction, moved south and eventually settled in North Africa in A.D. 429, long after this shield was buried.

The bones seem to have been part of a cremation, which was also a Vandal tradition. However, the archaeologists lamented in an Aug. 20 Facebook post that the original grave has been lost to time.

The newfound artifact consists of the shield's central iron "boss," or "umbo," which protected the hand while supporting the wood and leather of the full shield built around it. The wood and leather have now rotted away.

The shields of Roman legionaries also had a central boss. But the Romans never got that far north, and the pointed style of the boss indicates it is of second-century Vandal origin.

Junkyard find

According to the Facebook post, the shield boss was discovered earlier this month at a junkyard in the town of Hrubieszów, near Poland's southeastern border with Ukraine.

The man who found it immediately knew the artifact was very old, and he sent a photograph of it to the Father Stanisław Staszic Museum at Hrubieszów. Archaeologists there verified its likely origin, and the cremated bones were found during later examinations of a plug of dried earth inside the boss.

"The state of preservation of the umbo, especially its characteristic surface, indicates that it was exposed to high temperatures," museum representatives stated in the post. "This fact, combined with the burnt bones inside, clearly indicates the cremation burial of a warrior from the Vandal community." The Vandals are associated with the Przeworsk culture in Poland, after the town where evidence of them was first found.

"Unfortunately, we will probably never know what else was found in this destroyed burial ‪—‬ perhaps a sword, spearheads, javelins, a belt buckle, or a cloak clasp," the museum team noted.

See if you know what these mysterious artifacts are with our archaeological fragments quiz!

The ZWO Seestar S50 Pro was released on Aug. 25, 2026. It's a smart telescope that ships with everything you need to get started with astronomy and solar observations, eliminating the need to buy any other accessories.

It is controlled through the Seestar app on a smartphone and offers automatic slewing and autofocused views of galaxies, nebulas, star clusters and more. That said, in our experience, it sometimes needs manual adjustment with the on-screen joystick to perfect centering.

This being the Pro version of the original S50, which released three years prior, it's more expensive; you'll be paying $450 more than the original S50, with the S50 Pro coming in at $999. For that you get double the storage capacity (128 GB instead of 64 GB) and a higher resolution (4K not Full HD). ZWO claims the Pro has an extended battery life of nine hours, though we can't test this yet because the app version responsible for this uplift from the originally stated seven hours (version 3.3.1) wasn't released during testing.

So are these upgrades enough to warrant the extra spend?

ZWO Seestar S50 Pro review

ZWO Seestar S50 Pro: Design

• Lightweight and easy to carry in the case provided
• Dual-lens system mirrors the S30 Pro
• Simple, two-button design and an easy push-on solar filter

The Seestar S50 Pro is instantly recognizable as a smart telescope. A neat, rounded and glossy plastic casing protects the fragile but automatic optical and electrical insides that power this pocket rocket. Only two buttons are found on the entire device: a large power button on the side enveloped by a ring of light that glows when powered on, and a small reset button on the bottom of the telescope.

The carry case that the S50 Pro ships in looks like black compressed polystyrene but has neat latches and a red handle that tucks away in a slot at the top, making it easy to pack — similar to a drone case. This is much better than some of the bags you can buy for smart telescopes as it feels more rigid and secure. The S50 Pro and its tripod and solar filter all ship together and are snugly held inside.

It's light, too. We weighed it all, and the whole setup weighs 8.6 pounds (3.9 kilograms) fully packed, 6 pounds (2.7 kg) of that being the S50 Pro itself. It's also small; we measured it at 5.7 x 10.6 x 5.4 inches (146 x 270 x 138 mm), including the rubber feet on the bottom. Incidentally, we like that because it means you don't have to use the tripod if you don't want to.

We even received a bunch of ZWO-branded stickers that, if we were so inclined, we could pop on the telescope. But we're probably going to give them to the nephews.

Everything is controlled via the Seestar app, the same as all the other ZWO Seestar telescopes. This is typical for smart telescopes, which are almost always operated via an app.

As usual, and as we said in our S30 Pro review, it has a 3/8-inch tripod thread underneath, but the tripod itself is very small. We ended up using a larger photographic Gitzo carbon fiber tripod without the tripod head. But beware — if you're going to do this, take the tripod head off first. It won't fit the 1/4-inch thread of your standard mirrorless camera, which is likely what your tripod footplate will be.

ZWO Seestar S50 Pro: Performance

• Aligns and tracks automatically
• Live stacking reveals faint objects quickly
• Solar eclipses can be shot as photo or video timelapses

It took a matter of minutes for the live-stacking feature to give us clear and bright views of any object we slewed to. Live-stacking enables the smart telescope to take image after image to produce more detailed results of dim deep sky objects.

M27, the Dumbbell Nebula, was our standout favorite during testing, which we imaged over 10 minutes and 20 seconds. The final image captured the vibrant greenish blue core shining through, sandwiched by the red and orange glow of the nitrogen, hydrogen-alpha and sulfur.

Other notable objects we observed included M31 (the Andromeda Galaxy), which had good shape and reasonable clarity over the nine-minute exposure and filled the frame nicely considering this is an 8.3 MP image. It's also possible to image M81 (Bode's Galaxy) and M82 (the Cigar Galaxy) together on the S50 Pro due to the wider field of view, and after only 6 minutes and 30 seconds' exposure time we saw clear arms on M81 and fragmented detail and deep coloring in M82 which we were pleased with.

We also observed the sun, both before, during and after the Aug. 12, 2026 solar eclipse. Sunspots were clearly visible on the S50 Pro, and the solar filter that ships with the S50 Pro as standard gives it a warm orange tone, which is pleasing, even if we couldn't see much other detail like granules or faculae. However, we wouldn't expect that with a smart telescope of this spec at this price point.

Something that did frustrate us, though, was the S50 Pro's automatic exposure metering. This became most apparent during the Aug. 12, solar eclipse when taking a timelapse video.

The sun was overexposed most of the time, only allowing the darkest of sunspots to appear on the surface, but as the moon moved in front of the sun the exposure kept changing up and down, which it also did when clouds moved in front. The resulting timelapse was fun to share with friends and family over instant messaging but was far from ideal.

We also urge you to use a taller photographic tripod or similar when observing, due to our first session of nighttime imaging being obscured by a nearby tree bending into view during a long exposure, thanks to an occasional gust of wind.

ZWO Seestar S50 Pro: Functionality

• Smartphone app is easy to use
• A few niggles irk us, like typos and mislabelling
• Zero-backlash motor purportedly reduces wind interference

Setting up the Seestar S50 Pro is easy, and if we hadn't run into some synchronization issues with the app, or if we had used the NFC (near-field communication) feature, it could have been up and running in around five minutes.

Things being as they were, though, we had to restart and reinstall the app once or twice, with the telescope not visible to connect with in the app. It took around 30 minutes total, which is no big deal for a first-time setup, but it's something to consider.

There were a few niggles that struck us as odd, considering ZWO's outstanding ability to produce high-end astronomy products. Namely, we experienced the Seestar S50 Pro naming the sun as the moon (it was a few hours before the solar eclipse and it's possible it got visually confused because of the solar filter). There was also a typo when checking if the sun is "in the fram."

Plus, when observing long exposures, ZWO's Seestar mascot clung to the side of the screen and couldn't be removed. These are nothing super major but are all things we would like to see addressed before spending $999.

Everything about the S50 Pro's functions is almost identical to the S30 Pro, which we reviewed in April 2026. Live-stacking of 10-second exposures reduces the signal-to-noise ratio and improves details over time. It automatically slews to and autofocuses on subjects. The S50 Pro also has plate-solving in order to orient itself on the stars of the night sky as most smart telescopes do. It has an equatorial mode for better subject tracking, and it's operated by the same Seestar app.

One big difference, however, is the S50 Pro's zero-backlash motor, which is used for tracking subjects. Compared with the S30 Pro's stepper motor, which is internally geared, the S50 Pro has more precise tracking and better resistance to wind movement. We saw clear and sharp images produced during testing, but there was minimal wind on the nights we tested, so further observations are required to confirm how much of a difference this really makes to the average user.

Should you buy the ZWO Seestar S50 Pro?

If you don't have a smart telescope already and haven't tried any other ZWO smart telescopes, the S50 Pro is an easy win. It sits at the top of ZWO's smart telescope range, has the joint-largest aperture they offer, the joint-highest resolution and ships with everything you need to get started, even a solar filter for daytime observing. It's the best ZWO smart telescope currently available.

However, unless you have nearly $1,000 to spend on an instrument such as this, there are cheaper alternatives that do almost as well at a much lower price point. ZWO's own S30 Pro is $300 cheaper and bags a large amount of the same features and specifications as the S50 Pro. At nearly half the price, the S50 gives you the same aperture, but you will be restricted to much lower resolution.

If this product isn't for you

This striking satellite snap shows a series of ghostly green lakes that merged into a single murky entity after several years of unusual weather in the Australian outback.

The entwined lakes are located in Barkly Tableland, an area within Australia's Northern Territory, which lies between the states of Queensland, South Australia and Western Australia. The largest section of the conglomerate is Tarrabool Lake (on the left side of the photo), which stretches around 55 miles (90 kilometers) across at its widest point. It is dark green due to the dense vegetation and algae in the water.

The smaller half of the merged lakes (on the right side of the image) is made up of three lakes: Lake Sylvester, Lake Corella and Lake Deburgh. This section has a paler and chalkier hue due to high levels of suspended sediment. This is likely because the lakes have overflowed and mixed together, whipping up the dust and topsoil that once surrounded them. (Several other, smaller lakes of various sizes and shades of green can also be seen throughout the image.)

All of these lakes are ephemeral, meaning they have no constant inflow or outflow of water, much like most of Australia's other lakes. As a result, they almost completely dry out during prolonged periods of sunny weather, as high temperatures cause the water inside them to evaporate, and then reappear as heavy rainfall refills the basins.

However, across the two years prior to this image, there was so much rain that the lakes never dried out. Instead, they continued to grow year over year, as you can see from additional satellite imagery (see below), which shows the same area between 2022 and 2024.

The Northern Territory's rainy season lasts between October and April. Both the 2022-2023 and 2023-2024 rainy seasons, which preceded the 2024 satellite photos, were ranked among the top 10 wettest since 1990, according to NASA's Earth Observatory, which released these images.

Although this is extreme, it is not that surprising, considering that annual rainfall in the Barkly Tableland rose by around 14% between 1989 and 2018, according to a report from the Australian Bureau of Meteorology. This is likely due to the effects of human-caused climate change.

On top of the general increase in rainfall, Tropical Cyclone Megan dumped a massive amount of rain on the region in March 2024. The resulting flash flooding was so great that fish were seen swimming across a nearby road, Australia's ABC News previously reported.

In the winter, Tarrabool Lake and Lake Sylvester are important breeding sites for birds, including the straw-necked ibis (Threskiornis spinicollis) and the Australian pelican (Pelecanus conspicillatus), and BirdLife International lists both lakes as important bird areas. At its fullest, Tarrabool Lake also floods the surrounding Eva Downs Swamp system, creating Australia's largest wooded swamp.

See more Earth from space

Yellow fever is appearing in regions that haven't seen cases of the disease in years, largely as a result of climate change.

Historically, the virus ravaged cities across the Americas, Europe and Africa, until a vaccine was introduced in 1937 and its range shrunk significantly. But now, as climate change creates favorable conditions for virus-carrying mosquitoes, scientists are seeing outbreaks in unexpected areas.

"Yellow fever is a highly deadly disease," Dr. Joelle Ivy Rosser, an infectious-disease researcher at Stanford University, told Live Science, "so any environmental pressures that increase the likelihood of future yellow fever virus outbreaks … is highly concerning."

How is climate change contributing to this pattern, and could it get worse in the future?

How rising temperatures impact yellow fever

Yellow fever is a mosquito-borne disease caused by the Orthoflavivirus flavi virus, better known as yellow fever virus (YFV). The infection causes fever, muscle aches, headaches and vomiting. About 15% of cases become severe, with patients showing jaundiced skin and eyes, bleeding from the mouth, eyes, nose and stomach, or organ failure.

Devastating yellow fever epidemics spread in the 17th to 19th centuries, before the development of a vaccine. Nowadays, an estimated 31,000 to 82,000 yellow fever deaths occur each year; severe cases have an estimated fatality rate of 20% to 50%.

Most yellow fever infections are a result of spillover from nonhuman primates; mosquitoes bite monkeys that carry the virus, such as howler monkeys, and then the infected mosquitoes bite humans. Several types of mosquitoes carry the virus, but the species Aedes aegypti is the main vector for yellow fever in cities, where high population density can make outbreaks especially severe.

Although there is an effective vaccine for yellow fever, cases have been on the rise in the past three decades. This led the World Health Organization (WHO) to set out a strategy in 2017 for eliminating yellow fever epidemics by 2026 through outbreak prevention and containment.

Climate-change-driven warming and extreme weather events may have heightened yellow fever risk over the past few decades, experts say. Rising temperatures make mosquitoes bite more because heat makes their metabolisms more active, said Dr. Seth Judson, an infectious-disease physician-scientist at UCLA. Warming also cuts down the virus's extrinsic incubation period, meaning the time it takes for the virus to replicate in a newly infected mosquito and then get passed on to another person, he told Live Science.

Weather patterns and deforestation

Changing weather patterns play a role, too. In 2017-2018, Brazil saw its first yellow fever outbreak in a city in almost a century. That outbreak, primarily in Belo Horizonte and São Paulo, was likely a result of drought, according to one study.

While heavy rainfall creates a breeding ground for mosquitoes, in this case, drought pushed forest-based mosquitoes — as well as YFV carriers like marmosets and howler monkeys — closer to cities as the animals searched for water. Drier conditions can also prompt dehydrated mosquitoes to bite more as they search for fluids, study co-author Jamie Caldwell, a disease ecologist at Princeton University, told Live Science.

"Extremes of weather in either direction" — very wet or very dry — "can exacerbate mosquito-borne disease transmission," Rosser said.

Parts of Africa and South America that were considered low-risk for yellow fever have already been seeing new outbreaks, Judson said, so maps of yellow-fever-affected areas have had to be updated. In research that's been released as a preprint but not peer-reviewed yet, Judson found that yellow fever is reemerging in an area of the Colombian Andes where it hadn't been reported since 1940.

Experts are paying particular attention to the edges of cities, where urban centers meet the forest. The risk of yellow fever transmission from monkeys to humans via mosquitoes is rising at these edges due to both climate change and deforestation.

"Humans are expanding the agricultural frontier and encroaching on forests where yellow fever mosquitoes … are found," Gabriel Parra-Henao, a biologist with the WHO, told Live Science in an email. "[This] results in more people being exposed to their bites."

Similar patterns have been seen with other mosquito-borne infections, such as malaria.

Could yellow fever return to the U.S.?

Climate change is expected to bring yellow fever to new areas. One study predicts that, under the most severe climate change scenario, nearly a billion people could face their first exposure to the mosquitoes that can carry YFV in the next century. While that worst-case scenario may not be the most likely, the mosquitoes' ranges are still expected to expand under less-severe conditions.

Europe is predicted to face the largest increase in exposure to Ae. aegypti mosquitoes compared to the rest of the world, and the U.S. and Canada are predicted to see increases too. In the U.S., the mosquito species already lives in a number of states, including Florida, Mississippi, Arizona and New Mexico. However, warming would increase the chances of mosquitoes surviving in locations further north, such as Philadelphia and New York, which suffered major yellow fever outbreaks in the past. One model predicts Ae. aegypti could spread as far north as Chicago by 2050.

Although the mosquito lives in the U.S. already, yellow fever cases are exceedingly rare within the country because the virus is not present in local populations. That's because of an international campaign that the U.S. spearheaded in the 20th century, which involved researching YFV, eradicating mosquito breeding grounds, and vaccinating people widely.

"If yellow fever virus reestablished itself in our local Aedes aegypti population, then that would be very concerning," Rosser said.

One way yellow fever could return to the U.S. would be via people carrying the virus home with them after traveling to regions where the disease regularly circulates. Local mosquitoes could then catch the virus by biting those infected people, and then pass it on to others.

For local transmission to take hold, "there needs to be significant numbers of infections [passed to locals], and infections among travelers," Judson said. "But … it's in the realm of possibility."

With climate change driving resurgences of yellow fever in more places, and more regions of the U.S. becoming hospitable to the mosquitoes, that reintroduction scenario may become more likely. But some scientists think that even if North American cities saw yellow fever outbreaks, the outcome would likely not be devastating. Infrastructure in wealthier cities could be the difference between a disaster and a manageable health concern.

"There's access to medicines and vaccines; we pipe water to our homes, so we don't have standing water around," Caldwell said. "So it is a concern, but it's never going to be the next COVID."

Other experts noted that diligent surveillance of yellow fever infections can help public health officials prepare. In places where yellow fever is circulating in forest primates, forest conservation can limit contact among humans, wildlife and the mosquitoes that spread diseases among them. It's also crucial to make vaccines widely accessible to people who live in the virus's endemic regions and to travelers who visit those regions.

The WHO's yellow fever campaign is set to conclude at the end of this year, and its next steps are unclear. There's ongoing discussion of what comes next, Judson said, with questions about whether the control of yellow fever outbreaks will rely more on national strategies than on international coordination via the WHO.

Whatever happens, this is a time for heightened awareness of the virus, Judson said.

"We think of yellow fever as this historic disease," he said. "I think many people don't realize that we're still seeing significant yellow fever outbreaks. … It's really important to be aware of the risks and think about how we prepare for that."

This article is for informational purposes only and is not meant to offer medical advice.

Of the former National Football League (NFL) players who died in recent years, at least 25% had brain changes related to chronic traumatic encephalopathy (CTE), a new study suggests.

The study, published Aug. 25 in the journal The BMJ, examined donated brain tissue from 338 former NFL players who died between 2008 and 2021. A total of 1,712 former players died in that time frame, so the analysis included only about 20% of the players' brains that could theoretically have been examined. Then, the researchers used that subset of brains to estimate the likely prevalence of CTE in the overall group.

Among the donated brains, over 93% showed physical signs of CTE, meaning an accumulation of abnormal proteins in specific places within the tissue. About 30% had stage IV CTE, the most severe form that comes with the most extensive brain changes.

These physical signs of CTE aren't always associated with overt symptoms, such as cognitive decline, mood and behavioral changes, or dementia. Only about 60% of the individuals with CTE-related brain changes were also diagnosed with dementia in this study. That said, those with stage IV CTE were more likely to have dementia, with 90% having a diagnosis.

Across the full study time frame, the researchers estimated that between 18.5% and 98.7% of the deceased players likely had CTE. Zooming in on the period with the highest number of brain donations — 2016 to 2021 — they estimated the rate to be between 24.5% and 97.7%. That latter time frame was likely the more representative sample, the researchers determined.

What can this study tell us about the CTE risk that current football players face, from youth sports to the professional level? To put the research into context, Live Science spoke with Thayne Munce, an associate professor and director of the Jayhawk Athletic Performance Laboratory at the University of Kansas, who was not involved in the BMJ study. Munce researches brain health and concussion in contact sports, primarily among young athletes. He cautioned that the BMJ study's findings shouldn't be extrapolated to all levels and ages of play, or even to today's NFL players.

Nicoletta Lanese: This study estimated the rate of CTE among this era of NFL players. Was the prevalence surprising to you, or in line with your expectations?

Thayne Munce: It's not surprising to me. This group and their colleagues have published previous work from donors — so these are former players who have donated their brains for research. They have reported even higher rates than 25% among just their donor sample [in this study]. This really high rate — over 90% of CTE cases in the donor group — is in line with what previous research has shown for these brain banks. So that's not terribly surprising.

What's different in this study is they compared the donors over a certain period of time versus all of the deaths among NFL players during that period of time and estimated the range based on how representative that donor sample was to the overall group of NFL players.

For example, if players just randomly selected to donate their brain to the brain bank and then they found that 98% of all of their samples had CTE — if that's representative of all the players from that era, then that's where you get the higher estimate. But if the majority of players that actually had CTE were the only ones who donated their brains because maybe they were showing outward signs or symptoms of dementia or cognitive decline or behavioral changes while they were living, then it becomes a very highly biased sample.

So that's where you get this big range. [The true prevalence] really depends on how representative that donor sample was to the peer group of players from that era.

NL: Does that broad range of estimates make it difficult to pin down the risk for current players?

TM: I think even more problematic than that big range is to understand that this is a historical study.

So these were players who died between 2008 and 2021, and the average age, I believe, was a little over 70 years of age. So if you extrapolate backwards, they probably played in the NFL starting around age 21 or 22 or 23 — that puts their playing days back in the '60s and '70s. So these were players who played in the NFL predominantly in the '60s and '70s, and would have played college and high school football in the '60s and '50s.

This is a different era of football. So we should not be making any estimations about what current CTE rates are based on this study, because a lot has changed in 50 years. It [the CTE rate] could be the same. It could be greater. It could be less. We really don't know.

I suspect, based on improvements in protective equipment and rules and advances in sports medicine, that the risk is likely lower. I don't have evidence that that's the case, but nobody does. We don't really know how the rates today compare to in the past, since CTE can't be diagnosed in the living. We can't take a sample of current players and look to see how many of them have CTE.

But that is the challenge of this study. It's interesting [in that] it gives us a range of what CTE may be in that group of former players. But it doesn't give us a lot of information about what rates are in current players in the NFL. And even more so, whatever the CTE rate is in professional NFL players does not translate to former collegiate, high school or youth football players, because CTE is an exposure-related disease. For players who have less exposure to these repetitive head impacts, it should follow that they have a considerably lower risk of CTE.

We don't want to confuse a range of CTE prevalence from players who played 50 years ago with contemporary NFL players and definitely don't want to conflate that with what CTE rates may be for current high school and youth players, who have far less levels of exposure.

NL: You mentioned that football has become safer over time. Could you spell out how the game has changed?

TM: We can look at different categories: With the rules back in that era, spearing — hitting with the crown of the head — was allowed, and oftentimes encouraged, as a style of play. That's now penalized and not taught, or shouldn't be taught.

There are changes in equipment, for sure. Modern football helmets — the material, the padding, the way in which these manufacturers are using head impact data to construct position-specific helmets and materials that are designed now to not just prevent catastrophic injuries, like skull fracture, but also to minimize the force from having repetitive head impacts — that's come a long way.

There's the Guardian Caps; you may have seen the NFL has adapted those. So they wear these soft-shell hats on their helmets during the preseason and during practices. That's now required for many of the position groups.

Virginia Tech has a helmet rating system where they test football helmets, and every year, the helmets score better on these tests. They now have star ratings for youth helmets, so manufacturers of youth football helmets are now being held to account, as well.

Maybe the most important thing is just the education around and recognition of concussion and brain injury in the sport. Now, when an athlete has a concussion, they are more likely to be recognized for having a concussion and be pulled from play and have an opportunity to recover before they return to the game. You hear anecdotal stories of former NFL players from that era, like the '60s and '70s, that suffered multiple concussions, oftentimes in the same game, and were not removed from play and continued to practice under those conditions. That medical recognition and treatment management of concussion and brain injury has moved ahead.

You look at the way in which practice was conducted, from full contact, two-a-day practices, which were common even in high school 15, 20 years ago. Now it's really not allowed at any level of play. So the amount of hitting that they do, the amount of contact that players are exposed to in practice and in the preseason is far less.

NL: When players weren't able to recover from concussions, did that likely increase their brain-injury risk?

TM: Theoretically, yes. There's evidence that if the brain is injured and then it's exposed to a second insult or injury before it's properly recovered, that makes the condition even worse.

There's actually a term called "second-impact syndrome," and it's very rare, so I don't want to scare people. But there have been instances where players — it's often, unfortunately, young players, high school players — who have had a concussion which, in retrospect, went undiagnosed and then there was a second concussive blow that led to brain swelling and death. That's the extreme, but there are cases of that [repetitive damage] happening even on a lower scale.

Even if you don't get another concussion, just those nonconcussive repetitive head impacts on top of an injured brain would not be good. It certainly is only going to delay recovery, likely is going to compound your inflammation and all of the downstream consequences of that initial injury.

I suspect that that was fairly common in years past, mainly because concussions generally weren't diagnosed. No one was looking for them, and players certainly weren't encouraged to report if they had the symptoms. So it's very likely that many of these players, including the players that were in the [brain donor] sample, had concussions and played through them and continued to receive additional trauma on top of a brain injury.

Now whether that leads to CTE, we can't really say. But I think it's reasonable to suspect that it probably would increase that risk.

NL: Could you explain whether the physical signs of CTE in the brain tend to come with symptoms, like cognitive decline? Or is the link more nuanced?

TM: So CTE is a neurodegenerative disease that can only be diagnosed by neuropathologists — people that look at slices of the brain and look for particular proteins that are present in certain regions of the brain. [This examination is done after death.] It's a pathological marker. It means that there are changes in the structure of the brain.

The clinical side of that is changes in mood, cognition, behavior, things like dementia or cognitive decline.

Even in the study, they showed that they [the CTE brain changes and symptoms] weren't necessarily linked. Now I believe they showed that for those who had more severe CTE — like the stage IV — that there was a pretty high rate of those individuals who also had subsequently diagnosed dementia. They had these clinicians that looked at the records and diagnosed them. That's a little bit of a limitation of the study: that a lot of the dementia cases were diagnosed after the person had passed away, based on medical records.

To your more immediate point, the presence of CTE: So the presence of these markers in your brain does not necessarily translate into a clinical disease or a clinical diagnosis. There can be signs or symptoms that somebody may have — let's say memory loss or changes in behavior — that may lead someone, like a former football player, to suspect that, "Oh, maybe I have CTE because I played football and I've heard that that's linked with dementia."

That may be true, but it may also be that it's due to old age, or it could be due to genetics or some other condition.

Many of these neurological diseases and conditions can be managed clinically, and there's treatment. There's therapy; there's pharmacological treatments. There's a whole toolbox available for people to seek help. That's, I think, an important message for former athletes or individuals who may be concerned about developing CTE, is to recognize that there is a disconnect between clinical disease and the pathological disease. Just because you have some outward signs or symptoms that doesn't mean that you have CTE.

NL: Since there was a higher likelihood of dementia in the stage IV cases, it seems like there's a stronger link between the pathological and clinical diagnoses at advanced stages. Is that a fair read?

TM: Again, from this study and other studies, just the presence of CTE does not necessarily mean that somebody's mood, behavior, cognition is altered. It seems to be more likely — it seems to be a tighter relationship at the more severe stages, which would kind of speak to what you're talking about. A certain threshold of disease progression seems to be more likely to manifest itself in clinical disease [with overt symptoms].

NL: What should current NFL players take from this study?

TM: I would go back to what we discussed earlier: just understanding the time frame in which the study was performed and when those players were in the NFL. I think we need to be cautious about projecting those rates; it's a pretty wide range of estimates, and it has to do with how representative the sample is. We need to use caution if we are trying to interpret those rates for the current players.

If anything, I think it probably validates all of these efforts that we discussed to try to improve brain health and minimize risk of exposure.

Even if the prevalence is on the low end ‪—‬ that 25% of players who played in the '60s and '70s developed CTE ‪—‬ that's pretty alarming. That in and of itself should get the NFL's attention. Players shouldn't have a 1-in-4 chance or greater of developing this disease.

So let's take steps to reduce that risk — and I think it validates all of the changes that have taken place over the last 50 years. I mean, a lot of them have taken place over the last 10 to 15 years. That's probably the biggest message: to say we were right to do these things and we need to continue to see if there are further opportunities to make the game safer.

Hopefully we've made a lot of progress and current-day rates are much lower than they were in the past. We don't know that, but let's not be idle. Let's continue to push forward to reduce as much risk as possible in a game where you can't completely eliminate the risk. That's something that I think everyone acknowledges; every player has to acknowledge that there is some risk.

NL: Looking forward, what further improvements could be made?

TM: There's a couple of areas that are really in the infancy stages right now. If you think about brain health as a continuum where you would have a disease like CTE on one end and then optimal health on the other end — let's say repetitive head impacts take away from your brain health and tip the scale in favor of developing disease, what are things we can do to tip the scale back in favor of improving brain health?

We know that sleep is really powerful and could learn more about that in and of itself. And what about nutrition? What about pharmacological interventions? Wouldn't it be great if we could develop a medicine, a drug at some point that could be taken preventatively to reduce athletes' inflammation? Really looking into ways in which we can optimally improve brain health as a countermeasure to the damage or the trauma that is occurring.

It's not just football where these treatments could be helpful; it's also with soccer, hockey, other sports and occupations where there is exposure to [head] trauma. I think that's a promising area.

And then, certainly, diagnostic techniques. We talked about CTE only being able to be diagnosed at death. It would certainly be a game changer if we could diagnose it convincingly in the living so it could be recognized early. People are going to have different risks, and some of that is probably genetically determined; some people are going to have the same level of exposure and develop CTE while some aren't. If we could identify individuals who are at higher risk or in the earliest stages of the development of the disease, you can then change lifestyle, behavior, exposure — that would be huge as well.

NL: To shift gears slightly, could you describe your own research in youth sports?

TM: Most of my work over the last 15 years has been focused on youth football players. That's been an interest in measuring repetitive head impacts and neurologic function in youth football players and some work in high-school-age players, as well. So a lot of that is focused around subconcussive injury [head trauma that does not trigger overt symptoms of concussion, like nausea, light sensitivity or thinking issues]. We're looking at the effects of these nonconcussive head impacts on brain health.

That ties into the CTE question in the sense that CTE is thought to be due to cumulative exposure to brain trauma — repetitive head impacts — and certainly most of the work, like in this study, has been done in NFL players. The question for a lot of the general population is, "What about youth players, high school players, that make up 90% of all football players?" So from a public health perspective, it's those younger players that I think we really need to be studying and concerned about.

That's not to say this study isn't really important. It certainly is, but my focus has been on that younger population. And then I do have some experience working more in a hospital background [on] clinical concussion management and [developing] objective pictures of concussion.

NL: With recent research, do we better understand how those nonconcussive impacts affect brain health?

TM: Going back maybe 15 to 20 years, people started to recognize that there were some cumulative effects of concussion. Those were some of the earlier studies showing that former NFL players who had multiple diagnosed concussions had worse outcomes later in life — that kind of put the spotlight on concussion. Concussion went to the forefront, in terms of how we thought about brain injury in football.

And then, over time, this recognition of what has been termed subconcussive or nonconcussive brain injury has emerged, as there's been some imaging studies in collegiate athletes, and even high school athletes, that have found that players who don't get concussed sometimes have changes in their brain, even over the course of the season.

That dovetails with some of the CTE research which has shown that history of concussions isn't necessarily predictive of who developed CTE. It's more of a cumulative effect of repetitive brain trauma. So the CTE researchers have essentially concluded that it's history of repetitive brain trauma, rather than history of concussion, per se, that's a leading risk factor for CTE.

With CTE, it's always looking backwards, because it's something that's diagnosed at death. For researchers like myself who study concussion, or study active football players, that has also then been a reaction of saying, "Well, if it is repetitive trauma, if it's repetitive head impacts, that is a risk factor for neurodegenerative disease such as CTE, then that makes it even more important to study it in active players." What does that head impact exposure look like at different ages, and how can we reduce that exposure? How can we reduce the number and severity of head impacts that players are experiencing?

So there's both the CTE angle, which is, again, retrospective — I'm looking at former players. And the contemporary issues of players who are currently playing and what's the risk for concussion, but also what's their exposure to repetitive head impacts? So it's really tied together.

That's why there's so much concern about repetitive head impacts and why there have been rule changes at the collegiate and high school level about the amount of contact and limiting those types of activities, with the idea of reducing that overall head-impact burden.

NL: When you talk about repetitive head impacts broadly, I assume that covers both concussive and nonconcussive impacts?

TM: Yep — so every hit would be considered a head impact, and then certain impacts are strong enough, or hit you in the right spot, to cause a concussion. The vast majority of impacts are nonconcussive.

NL: How do you speak to these athletes' families about the risks of concussion and CTE?

TM: When I do talk to players and coaches and parents, I often like to remind them that, generally, the benefits of playing sports, including tackle football, outweigh the risk. Oftentimes we get so concerned about the risk, which is real, that we forget about the benefits and about the alternatives of not playing. Almost always, the benefits — from the physical, the psychological and social components, the mental health components — are going to outweigh the risks. That's one thing to keep in mind.

Second, the risk of injury — in this case, CTE — is likely going to be far less in those younger players than older players, NFL players because their exposure, the number of impacts, the severity of impacts is far less. With my research, I've measured those head impacts and compared them to high school players and collegiate players, and extrapolated to NFL players because that data isn't available. And you see this big stepwise increase in exposure from the youth, the high school, the collegiate, to the NFL players.

[With parents], I'm reassuring them that the risk is far less for the younger players than what they hear about in this type of study. We're talking about an apples-to-oranges comparison.

I also like to remind them that, in my opinion, the game of football has never been safer. I've got a bit of a personal perspective on this as well, because I played football myself through college.

NL: Who did you play for?

TM: I played for a Division II school in South Dakota called — it's Augustana University now; it was Augustana College when I played there.

So I played 12 years of tackle football, and I can compare what tackle football was like when I was in fifth grade versus now — with the training that coaches have and the type of equipment they have and the way the practices are structured. It's completely night and day.

Even at the collegiate level, the way in which collegiate practices are conducted and the safety measures that are in place for current collegiate players is nothing like what we had when I was playing. So I like to reassure players that this is probably the safest time to be playing the sport of football.

At the same time, I acknowledge that this is an individual decision that parents need to make with their kids and evaluate that risk. One of my goals as a researcher is that I want to provide more empirical evidence so that they can make an informed decision, so that a parent would be able to say, "My son's risk of getting a concussion while playing youth football is 1 in whatever" — you know, 1 in 10, 1 in 5, or 1 in 100, whatever that case may be. And his risk of getting CTE by playing four years of youth football or four years of high school football would be this. Then you make an informed decision. Is that risk worth the benefit of participation?

Unfortunately, we don't know what that risk is [currently]. We can't tell parents, "Here's objectively what your risk of injury is going to be." It makes it tough for parents. So I like to reassure them that a lot of the concerns that are expressed for NFL players are greater than they should have as parents of youth players.

This interview has been condensed and edited lightly for clarity. It is for informational purposes only and is not meant to offer medical advice.

See how much you know about the most complex organ in the human body with our brain quiz!

If you blow across the top of an empty bottle you'll hear a clear, steady note. Now, engineers have used that same concept to power tiny robots that move without a single motor on board.

These new devices are powered entirely by sound. When the right frequency is aimed at them, hollow chambers built into their structure resonate and push out a jet of air, generating enough thrust to steer a small boat or lift a tiny flying robot off the ground.

The scientists described their innovation in a study published Aug. 12 in the journal Science Advances.

A 19th-century tuning trick, miniaturized

The effect behind it, known as Helmholtz resonance, was first studied in 1856 by the German physicist Hermann von Helmholtz, who was trying to invent a tool for tuning musical instruments. He noticed that when air trapped inside a cavity resonates, it also pushes out a faint jet of air.

"It isn’t very powerful when you do it with a musical instrument, because pressure is low," said study co-author Selman Sakar, an associate professor of mechanical engineering at the Swiss Federal Technology Institute of Lausanne (EPFL) in Switzerland. "But if you could crank up the pressure, all of a sudden that jet could become significant... in a way that the force can be harnessed for machinery," he told Live Science.

The team realized that shrinking Helmholtz's resonators down would push the frequency needed to activate them into the ultrasonic range — meaning it's too high-pitched for humans to hear and, crucially, easier to focus with precision. Larger versions generating the same force would need audible sound loud enough to be both annoying and potentially harmful, Sakar said.

Using a specialized 3D-printing technique called two-photon printing, the researchers built hollow structures based on Helmholtz's original equations and confirmed with lab tests and computer simulations that they generated thrust as predicted.

Boats, rockets and tiny helicopters

The team built small boats measuring roughly 2 inches (5 centimeters) fitted with multiple resonators, each tuned to a different frequency and pointed in a different direction. By changing the pitch of a nearby speaker, the researchers could steer the boats left, right or straight ahead.

At a far smaller scale — some just 0.04 inches (1 millimeter) across — the team also built "microfliers" that generated lift two different ways: some pushed thrust downward like a rocket — but using air for the thrust — while others span tiny attached blades to fly like a helicopter, using sound waves to rotate the blades.

The technology has an advantage over conventional means of power generation because it can be built at extremely small scales, Sakar said. Conventional motors have "a fundamental limit" on miniaturization because of the physical components like magnets, coils and shafts that a motor needs to work, he said. Because these resonators are just precisely shaped hollow cavities, there's no comparable limit on how small they could eventually build.

The researchers said in the study that the same principle could eventually be used to precisely rotate and manipulate small objects in midair without touching them, or to build soft, flexible surfaces that bend and change shape on command when they "hear" a particular frequency which can be used for biomedical applications like heart stents.

For now, the study is a foundation for the researchers to build on, Sakar said. "This paper, I think, is important in the sense that we put the design principles out," he said, adding that follow-up work could focus on more applied designs, control systems or navigation.

At the beginning of the 20th century, a German art collector acquired dozens of artifacts from a Russian-led excavation of an ancient Hun settlement in Crimea. The most spectacular piece of the collection was the Crown of Kerch ‪—‬ a garnet-studded, gold diadem featuring stylized birds of prey.

The artifact, which is now on display at the Neues Museum in Berlin, is made up of three gold-covered, bronze plaques and more than 250 gem-studded cells. According to the museum, the crown was discovered in the grave of a high-status woman buried in the ancient city of Pantikapaion on what is now the Kerch Peninsula of Crimea.

The band of the rare gold diadem is roughly 1.7 inches (4.4 centimeters) tall and is associated with the fearsome nomadic warriors known as the Huns, who moved west from the Don River in what is now Russia in the late fourth century A.D.

Pantikapaion was founded as a Greek colony in the sixth century B.C. but was conquered by the Huns in the late fourth century A.D. A large necropolis with as many as 2,000 burials was excavated at Pantikapaion in the early 20th century, but only a handful of artifacts and skulls were saved from the excavation. Pantikapaion was incorporated into the Byzantine Empire in the sixth century by Emperor Justinian I.

The Crown of Kerch features two stylized heads of birds of prey, likely eagles, flanking a central floral motif. Round, green gems mark the birds' eyes. These birds likely represented power and authority among the Huns and other groups, according to the museum, and they were a popular symbol on jewelry and accessories of the time. Similar birds of prey have been found on Visigoth women's jewelry in Spain from the sixth century, for example.

German archaeologist Joachim Werner wrote in a 1956 study that the Crown of Kerch was found in a burial chamber near the skeleton of a woman with an artificially modified skull. Although the woman was buried with the diadem, Werner believed that these items were not just used for grave goods, and that high-status Hun women regularly wore the accessory during life, possibly with a cloth cap or veil attached.

Around two dozen examples of similar gold diadems have been discovered to date. This suggests that the Crown of Kerch is not technically the royal insignia of a queen but rather a diadem worn 1,600 years ago by a member of the ruling Hun elite.

For more stunning archaeological discoveries, check out our Astonishing Artifacts archives.

Can you put together last week's Astonishing Artifact?

Photovoltaic technology, most commonly seen as the bulky solar panels used on solar farms, is expected to become a dominant energy source by 2050. But these panels are often installed on land that might otherwise be used to grow crops for feeding a burgeoning population.

Agrivoltaics aims to solve this problem by planting crops around or underneath rows of solar panels, allowing for more efficient land use. In previous studies, solar panels were shown to help shade and protect certain crops as well as increase soil moisture, suggesting that carefully designed systems could support both agriculture and clean energy production.

Existing agrivoltaic research, however, tends to focus on one aspect of this process at a time — for example, light availability or crop growth — rather than addressing the nuanced interactions between microclimates, crop type, light, and panel type. Hosseini et al. share a new model that can simulate the microclimates beneath solar panels and even addresses the heat stress that workers might face in actual conditions.

The new model simulates the interactions between solar panels, crops, soil, air and water movement, and carbon dioxide uptake by tracking how energy, momentum, and mass move through the agrivoltaic system. The researchers used agrivoltaic site data, including leaf temperature measurements taken in Davis, Calif., and soil temperatures taken in Chicago City, Minn., to assess how the model's efforts matched real-world conditions.

They then applied the model to a hypothetical agrivoltaic tomato farm using weather data from a hot, humid day in Princeton, N.J., a representative location for the densely populated mid-Atlantic region, where food and energy are both in high demand.

Compared to tomatoes grown in an open field, tomatoes grown under solar panels experienced leaf temperatures that were 1.84°C cooler during the day overall and up to 7.56°C cooler during peak afternoon heat, reducing water loss through evapotranspiration by 22.4%. Even though the simulated crops received 47% less sunlight, their carbon uptake declined by only 31%, suggesting that more temperate conditions lowered heat stress and partially offset the effects of increased shade.

The solar panels themselves were also 5.6°C cooler during the daytime than panels in bare soil, allowing them to recover about 15% of the efficiency that is lost during hotter temperatures. The average perceived temperatures for humans decreased by 4.46°C during working hours, implying important occupational health and safety benefits for farmworkers. The researchers suggest this model can be used to examine the benefits of agrivoltaic farms as well as other climate and crop combinations.

In July, a government agency tasked with protecting our cultural heritage abdicated its responsibility, voting to further industry's pursuit of profit over protecting sites of cultural significance. The Advisory Council on Historic Preservation (ACHP), the only federal agency whose sole mission is promoting preservation of America’s historic places, voted to advance a proposed new rule that would make sweeping changes to how Section 106 of the National Historic Preservation Act is implemented. By doing so, the Council is opening the door for federal agencies to bulldoze sacred Indigenous sites and important archaeological sites.

Section 106 requires federal agencies to assess the effects of their actions — or the actions they license or permit — on historic, archaeological, and cultural properties listed in or eligible for listing in the National Register of Historic Places. Additionally, agencies must attempt, to the extent possible, to minimize harmful effects on these significant places. The rules governing Section 106 have been in place since 1974. As part of that framework, the government is legally required to consult with Tribal Nations about projects that may destroy or damage their sacred places or culturally significant resources.

The proposed new regulations destroy the idea behind consultation. For instance, they would give federal agencies the discretion to decide whether public participation will be useful. Essentially, the agencies get to decide whether to notify the public or provide opportunity for public comment before they approve projects that might damage or destroy historic properties.

It would also give federal agencies the right to approve projects that may damage or destroy Tribal sacred places and other culturally significant resources without consulting with Tribal Nations or seeking their expertise about them. This violates federal law and jurisprudence, which recognizes Tribal Nations as "domestic, dependent nations," and requires consultation with them on a government-to-government basis; Tribal Nations are not merely “interested parties” like community organizations or local groups.

An agency official would prepare a "Section 106 report" that identifies historic properties, assesses impacts, and makes a determination on next steps; this Section 106 report would then be circulated to State Historic Preservation Officers, Tribal Historic Preservation Officers, and all relevant consulting parties — including project proponents — who would have an opportunity to comment on the findings. The agency official must only review those comments; officials have no obligation to respond to or incorporate any of those comments before issuing the final decision, shifting Section 106 from its previous consensus-seeking exercise to one where the agency official simply decides.

The new regulations also remove vast swaths of our history from protection. To be considered a historic property, the new regulations say it must include, or have included, tangible human improvements – built structures – AND the historic property must be geographically compact. This change in definition will exclude entire categories of historic places from meaningful consideration under Section 106 in the future, including battlefields like Gettysburg or the Little Bighorn, cultural landscapes like Devil’s Tower in Wyoming or the Black Hills in South Dakota, archaeological resources like petroglyphs in Chaco Canyon. It lessens protection on places like the Grand Canyon, simply because they are not “geographically compact” or centered on a building or other structure.

The new regulations specifically preclude "noncompact, unimproved natural features such as mountains, valleys, bodies of water, or landscapes, including ethnographic landscapes" — locations that carry great spiritual and historical meaning to American Indian groups. Many traditional cultural places and sacred sites of deep religious and cultural significance to Tribes, Native Hawaiian organizations, and local communities will automatically be excluded from consideration for protection by the new regulations.

The changed definition of "historic property" in the new regulations will remove protections for 99% of American Indian heritage and could result in the erasure of the heritage of an entire group of people in the United States – those who lived here before European colonization.

Mitigation, or trying to prevent, minimize or offset any damage to a historic site, becomes a “maybe,” as the federal agency undertaking the project decides whether the "value" of the property is worth the cost of mitigation. "Reasonable mitigation" is redefined so that federal agencies only have to consider measures to lessen the impact of a project on a historic property if they are "technically and economically feasible."

The new regulations water down the definition of what is considered to be an "Adverse Effect" on historic properties so that they are close to meaningless. By removing indirect and cumulative effects on historic properties and eliminating the visual, atmospheric or audible elements that diminish the experience at a property, the new regulations could say that building and operating a casino or amusement park on Mount Vernon would not be considered an Adverse Effect.

Additionally, agencies will not be required to avoid or minimize adverse effects. They can simply document that “other considerations outweigh” historic preservation and proceed as they wish.

Advocates of the new regulations argue that the existing regulations for protecting historic places slow down projects and make economic development more expensive than necessary. They say these new regulations create a system that allows industry to plan better with more precise information, and the processes and procedures are better explained. They argue that the narrower definitions and expanded exemptions could mean faster, more predictable reviews. In reality, however, the rules that are already in place seek to balance the need for economic development with the need to protect the fabric of America’s heritage.

I remember urban renewal and its impact on Oklahoma City in the early 1960s, as large, beautiful buildings in the downtown area were bulldozed to rubble and hauled away so that new, shiny structures could replace them. I remember entire neighborhoods of working-class people being leveled so that an Interstate highway could be constructed through the center of town to let millions of people speed through without having to see the “urban blight” that was erased. I remember, too, the historic properties that disappeared under the developer’s bulldozers and graders.

Those memories are fading fast, I must admit, and the historic properties are long gone. The National Historic Preservation Act was established to help prevent the destruction of the property of economically weaker groups of people at the behest of the economically strong without some level of consideration of the heritage under threat by construction; the Section 106 regulations grew out as a result of that time and has been seen to be a good compromise between economic development and economic justice.

The new regulations serve to weaken everything that has worked about Section 106 for the last 50 years so the federal government has the power to quickly green-light industry's ground-disturbing projects without considering the impact of its actions on America’s heritage. Agencies may proceed as they wish, since the new regulations mute the voices of states, tribes, and local communities who are at the forefront of identifying and protecting American heritage.

The new regulations are currently under review with the Office of Information and Regulatory Affairs (OIRA) within the White House Office of Management and Budget.

There is a chance that the administration will use a rushed rulemaking process that bypasses public comment, meaning the regulations will take effect when published.

But bringing visibility to the proposed changes could potentially forestall that, and so people who are concerned should contact their local congressional representatives to tell them the changes are a threat to all American's heritage.

If these changes are not stopped, our children will hold us accountable for letting our shared heritage be erased merely for the convenience and benefit of a few.

Opinion on Live Science gives you insight on the most important issues in science that affect you and the world around you today, written by experts and leading scientists in their field.

In this single Hubble Space Telescope image, tens of thousands — possibly millions — of stars bound tightly by gravity sparkle as one. This is NGC 6723, a glittering globular cluster about 27,000 light-years away, in the constellation Sagittarius.

Also known as the Chandelier Cluster, this swarm of stars is one of about 150 known globular clusters that orbit in the halo of the Milky Way, though others may remain hidden behind thick cosmic dust or crowded star fields at the galaxy's bright core.

Globular clusters like NGC 6723 are among the most ancient structures in our galaxy. What baffles astronomers most is the age of the stars within them. These clusters often contain stars older than 10 billion years, with some dating back almost to the beginning of the universe itself 13.8 billion years ago. They likely formed early in the history of the Milky Way, billions of years before the thin disk of stars where the sun now orbits took shape.

It was once thought that all stars inside a globular cluster formed at the same time, from the same material, during a single burst of star formation. If that were true, the stars would have the same age and chemical composition.

However, Hubble's view demonstrates that this is not the case. The cluster is densely packed at the center, where many bright-blue stars appear concentrated, while orange stars are more prominent toward the edges. Blue stars are younger than orange stars, suggesting that globular clusters can have complex histories, with different populations of stars and subtle chemical differences among them.

Hubble first observed NGC 6723 in visible and near-infrared light as part of a major survey of 65 globular clusters in 2013. It found that massive stars sink toward the center of a cluster, while lower-mass stars drift outward. In 2013 and 2014, Hubble studied NGC 6723 to search for small chemical differences between stars and to measure the spread of ages of stars within the cluster. Two epochs were found, with the second burst of stars happening about 634 million years after the first.

One leading idea is that globular clusters formed when enormous gas clouds collapsed rapidly in the early universe. However, recent simulations also suggest that some globular clusters may be the surviving cores of ancient dwarf galaxies that were stripped of their outer stars by larger galaxies. Either way, they're a fossil remnant hinting at how galaxies evolve.

Globular clusters are not unique to the Milky Way. They are found around many kinds of galaxies, including spirals, giant ellipticals and dwarfs. The Andromeda galaxy, the nearest large spiral galaxy to the Milky Way, is estimated to host about 460 globular clusters, while the giant elliptical galaxy M87 contains roughly 15,000 globular clusters, according to NASA.

Every second of every day, Earth is bombarded by particles from outer space. Some of these particles are obstructed by our planet's atmosphere but can spray down other particles, while others can zoom through the atmosphere and easily pass through anything, including us.

You won't feel these particles darting through you, but it raises a question: How many cosmic particles are actually passing through your body at any moment?

The most common particles that stream through us from outer space are ghostly specks known as neutrinos. "An estimated 100 trillion neutrinos pass through each of us every second," Michael Pravica, a professor of physics at the University of Nevada, Las Vegas, told Live Science.

Neutrinos barely interact with regular matter. Nearly all of them pass through us and the rest of the planet without leaving a trace. "The fact that most of these particles never interact with us demonstrates that there is an underlying reality to our existence, much of which we are not even aware of," Pravica said.

Neutrinos originate from nuclear activity. Nearly all of the neutrinos zipping through us come from the nuclear fusion reactions that power the sun, although some neutrinos originate much farther away, even other galaxies, Lu Lu, an assistant professor of physics at the University of Wisconsin-Madison, told Live Science.

Other extraterrestrial particles that continually strike Earth are cosmic rays — electrically charged, highly energetic particles that travel at nearly the speed of light from all directions, according to the University of Chicago. Although the sun's nuclear reactions produce very-low-energy cosmic rays, the vast majority of cosmic rays come from beyond the solar system. These may be created when faraway stars explode as supernovas, matter falls into supermassive black holes, or galaxies collide, per the University of Chicago.

Cosmic rays are mostly either protons, which are the nuclei of hydrogen atoms, or the atomic nuclei of heavier elements (which contain both protons and neutrons), such as helium or iron. Electrons and positrons (the antimatter counterparts of electrons) also make up a tiny fraction of cosmic rays.

When cosmic rays hit Earth, they are generally blocked by molecules of air high in our planet's atmosphere, Lu said. However, these collisions can generate showers of secondary particles that make it to the ground. These include muons, which are negatively charged subatomic particles that are much like electrons except more than 200 times more massive.

At sea level on Earth, about one muon passes through per 0.15 square inch (1 square centimeter) per minute, Lu said. "For a person, the number ranges from tens to hundreds per second," she noted. "Roughly one or two pass through a hand each second."

Because muons are electrically charged, they can interact with matter they encounter. "Their paths can be made visible in a cloud chamber," a box of vapor in which a trail of mist can be seen when a charged particle streaks through the vapor, Lu said.

In contrast, neutrinos are not electrically charged. They also have almost no mass. These two qualities make it very difficult to detect neutrinos, which is why they're often dubbed "ghost particles."

Detecting cosmic particles

Scientists estimate the number of neutrinos that pass through our bodies by recording "the tiny fraction that happen to collide with matter inside or close to a detector," Lu said. "Everything else follows by working backward from those few."

For instance, the IceCube Neutrino Observatory in Antarctica surrounds 0.24 cubic mile (1 cubic kilometer) of ice with thousands of light sensors. "When a neutrino interacts with an atomic nucleus in the ice, it produces fast-moving charged particles, and those particles emit a faint flash of blue Cherenkov light, which the sensors record," Lu said. "From the pattern and brightness of that light, we can reconstruct the neutrino's energy and direction."

To estimate how many neutrinos pass through Earth based on these recorded interactions, "we account for the size of the detector, how long it operated, its detection efficiency, and the probability that a neutrino of a given energy interacts at all," Lu said. "It is a bit like estimating the number of fish in a river from the few caught in a very coarse net. If you know the size of the net, how long it was in the water, and how easily fish slip through it, you can work backward to the whole river."

When it comes to the neutrinos that IceCube studies, although trillions pass through each of our bodies every second, nearly none of them interact with our atoms. "You would expect no more than roughly one interaction in your body, perhaps a few, over an entire lifetime," Lu said.

These rare interactions would have virtually no effect on us. Given how little energy such an interaction would deposit, such neutrinos "pose no health risk at all," Lu said.

In contrast, the showers of particles resulting from cosmic ray impacts can potentially affect human biology. "At ground level, muons dominate the penetrating charged particles reaching us from cosmic-ray showers," Lu said. "At higher altitudes, and especially during air travel, other secondary particles, particularly neutrons, contribute a significant share of the biologically relevant dose."

Still, any effects from these cosmic-ray showers are generally small. "For an average person, cosmic radiation contributes roughly 0.4 millisieverts per year, about the same as a few chest X-rays spread across the year, out of a total natural background of about 2.4 millisieverts from all sources," Lu said. "The dose varies with altitude, latitude and shielding. At typical ground level, muons and other cosmic-ray particles are not considered a significant health hazard. Life on Earth has been bathed in them from the beginning."

So, every second, there are about 100 trillion neutrinos and tens to hundreds of muons passing through your body per second, and maybe a tiny scattering of neutrons and other cosmic particles or debris from cosmic particles impacting the atmosphere.

These cosmic particles may lead to a variety of discoveries. For instance, scientists have used muon detectors to identify hidden passageways in pyramids. And "high-energy neutrinos allow us to study some of the most violent and otherwise hidden environments in the universe, such as the regions surrounding black holes, exploding stars and other powerful cosmic accelerators," Lu said.

"Because neutrinos interact so weakly, they can escape from dense regions that light may not be able to penetrate," she explained. "They therefore carry information directly from the places where some of nature's most energetic particles are produced."

All in all, "the particles streaming through us are a constant reminder that we are not separate from the universe," Lu said. "We are part of a cosmic story stretching back 13.8 billion years."

See how much you know about black holes with our black hole quiz!

Archaeologists in Russia have unearthed a medieval hoard of 2,600 silver coins, including more than 350 coins of a type never seen before. The hoard may have been buried by a nobleman who later fell victim to a plague.

The coins were found in an elegant ceramic jug, according to an Aug. 26 translated statement from the Institute of Archaeology of the Russian Academy of Sciences. The jug was buried in a pit in what is now the historic center of Kolomna, a city about 71 miles (114 kilometers) southeast of the city of Moscow. In the 14th and 15th centuries, Kolomna was the second-most-important city in the region.

Most of the silver coins are a type called a denga. Dengi were first minted in the late 14th century by the Grand Principality of Moscow, a late medieval Russian monarchy. Each denga was worth half a kopek, and there were 100 kopeks to a ruble. The coin hoard is dominated by coins minted in Kolomna under Vasily I (who reigned from 1389 to 1425) and Vasily II (who reigned from 1425 to 1462), according to the statement. These rulers were both grand princes of Moscow, as the city and its wider region were part of an independent principality at the time.

One of the most interesting coin types is an extremely rare denga that features a bird in flight, which was produced during the final years of the reign of Vasily I, according to the statement. Additionally, more than 350 of the coins are previously unknown varieties minted in Kolomna, which experts are now studying.

The person who buried the Kolomna hoard was likely a wealthy, high-status person, such as a high-ranking government official or an extremely successful merchant, according to the statement.

While it is unclear why the hoard was buried, experts think the date of the coins provides an important clue. The most recent coins were minted in the second half of the 1420s, according to the statement. This suggests that the hoard's owner could have fallen victim to a plague epidemic that swept through Russian principalities from 1424 to 1427.

See if you know what these mysterious artifacts are with our archaeological fragments quiz!

Earth's temperatures are steadily rising, with the past decade experiencing all 10 of the warmest years on record. As heat waves become more frequent and intense, concerns are growing about how this heat could impact people's health.

Higher temperatures can have serious effects on the human body, including dehydration, heat exhaustion and heatstroke. But extreme heat can also drive up the rates of heart attack and strokes due to ill health.

In a Live Science poll, we asked our readers how concerned they are about rising temperatures affecting their health and fitness, daily activities and the safety of their community. Over 170 people responded to the poll, which was published Aug. 26, with 67% of readers voting "Yes, I'm very worried about how extreme heat is affecting everyone around the world."

The comments from readers also reflected their concerns. One commenter wrote, "Too much of humanity is unaware that the Earth is a single organism. Everything is connected. El niño may begin off South America but its effects are eventually felt everywhere. There is only one ocean."

Another reader mentioned the daily challenges caused by the rising temperatures, saying, "I've been trying to make walking around the block of my neighborhood a regular thing, but when it gets too hot (and more precisely too humid) I prefer staying inside my house where I can be comforted by the AC."

So what do you think? After reading these responses, are you also worried about extreme heat? Let us know in the comments.

A new artificial intelligence (AI) model used a novel approach to AI cognition to dramatically reduce the cost of requests, suggesting that nonverbal reasoning may be the next step toward machines developing human-like intelligence.

In a new research paper published Aug. 10 on the preprint server arXiv, scientists at AI company Pathway detailed the technical foundations of its new BDH-CQ model. This follows a precursor model known as "Dragon Hatchling" that the scientists created in 2025, which was designed to accurately simulate how the neurons in the brain connected and strengthened during the learning experience.

In the new study, the scientists described how they evaluated BDH-CQ's performance against a foundational 2019 benchmark that helped set the current standard for measuring progress toward artificial general intelligence (AGI) — the point at which AI has matched or surpassed human capabilities in all domains.

The 2019 benchmark, known as ARC-AGI, uses nonverbal reasoning puzzles — such as rotating a series of shapes to complete a sequence — to measure the cognitive ability of AI systems. Whereas humans are highly skilled at inferring the rules of these types of puzzles through trial and error, early AI systems were historically much less skilled.

BDH-CQ scored almost 30% on the ARC-AGI-1 benchmark, successfully solving the equivalent of three out of 10 puzzles in two or fewer attempts. Although numerous models have achieved significantly better scores on this test, the underlying reasoning approach that BDH-CQ is based on makes its size and usage costs dramatically smaller than models built atop the traditional transformer-based architecture.

For example, while OpenAI's entry-level lightweight reasoning model GPT 5.6 Luna (Low) achieved a slightly higher score, the study stated that this "modest accuracy gain" cost roughly 11 times as much as BDH-CQ in terms of relative token costs — the metering system that AI companies use to measure the cost of running AI systems. This type of AI model architecture, if adopted widely, could have a dramatic impact on the overall cost and scale of AI deployments, the scientists believe.

More than meets the eye

BDH-CQ was trained on just 150 million parameters, while parameters for the most advanced, "frontier" AI models such as Meta’s open-source Llama 3 70B or Llama 3.1 405B typically number tens of billions to hundreds of billions. In the world of AI development, fewer parameters means that models are faster to train and cheaper to run.

The researchers, however, said these results also imply that the model's cognition capabilities could scale significantly when expanded to larger parameter sizes.

The reason for this performance jump is that Pathway's model uses what the company's scientists describe as a "post-transformer" architecture.

Most mainstream AI models, such as those powering Claude and ChatGPT, are based on "transformer models," so called because they transform user inputs into interconnected mathematical reference points. These systems look at every word within an input simultaneously, which allows them to infer context from position, such as deciding based on nearby words whether the word "bark" refers to dogs or trees.

A transformer model forms its responses to user queries by looking at the full prompt simultaneously and then predicting what the next word in the sequence of its reply should be. It does this word by word, using natural language to effectively verbalize a linear train of thought in the background. Transformers' reasoning also functions sequentially, meaning they have to work through each stage of a problem in a strict linear order.

These models have significant advantages over earlier architectures, which would often forget the start of an input by the time they reached the end. However, transformer architectures can struggle with longer or more complex prompts, as the computational complexity of evaluating the prompt increases quadratically — meaning that doubling the length of an input uses four times as much processing power.

AI model usage is measured on a per-token basis, with a token representing any data fragment (equivalent to roughly four characters of text) that the AI has to ingest or output. Because more complex prompts require longer trains of thought with multiple steps, processing and responding to these queries can burn through significant amounts of tokens.

AI's next generation?

Conventional transformer-based token generation is prone to causing memory bottlenecks, as AI re-reads every previous word in the conversation with every new word generated. Eventually, this will clog up the memory in the graphics processing units (GPUs) used for AI operations.

Because of this, scaling AI reasoning has become an expensive computational challenge. Pathway's post-transformer approach changes how the AI’s memories of a conversation and the relationship between pieces of information are stored and processed. It replaces text logs with new tools, including an improved short-term memory and a mechanism that allows it to work through problems without consuming tokens.

Transformer-based models retain prompts and interaction histories as a long string of numerical values representing the text of requests. That string then expands as new tokens are added through processing the request. BDH-CQ uses numerical arrays to represent the underlying rules and contextual patterns of a task, using numbers to track relationships between chunks of information rather than defining them in text.

These arrays represent vectors — directional information that points to another point on a theoretical map stored inside the GPU’s memory as part of the training data, implanted during the model's creation. The scientists said in the study that this allows the model to process complex abstract reasoning without increasing its memory footprint or computational cost.

To execute tasks, BDH-CQ implements a "latent reasoning engine" as its internal workspace. Using numbers to represent the different elements of a prompt or problem, it carries out a series of iterative recurrent loops to determine the best answer to return based on the prompt. The model takes the output of the last loop, assesses how the result could be improved based on its training data, and feeds back the previous output as the starting point for the next iteration. It repeats this for a pre-set number of loops, with each iteration theoretically closer to the desired outcome.

To tackle more complex problems requiring more thinking time, BDH-CQ can execute more loops. This increases the time taken, but the amount of memory and computational power consumed does not scale with more attempts — in theory, the model would consume a consistent proportionality of memory and power running 200 loops as it would running 20 loops. Standard transformer models, by contrast, achieve extra thinking time by generating long chains of written text tokens, which exponentially consumes GPU memory and computing power across an AI cluster.

The model's ARC-AGI-1 benchmark results have been independently verified and reproduced by prominent researchers in the AI field, including NYU researcher Richard Zhong, and Łukasz Kaiser, a co-author of the seminal 2017 paper "Attention Is All You Need," which introduced the concept of transformers within large language models.

"I've followed Pathway closely and replicated their ARC-AGI-1 results myself," Kaiser said in a statement. "Pathway shows that model architecture, not just scale, can drive the next leap in AI reasoning."

Pathway plans to scale the BDH architecture up to 600 billion parameters and apply its vector-based reasoning to more challenging benchmarks, such as ARC-AGI-2 and ARC-AGI-3, as well as develop a fully-fledged large language model (LLM) based on the technology, which would provide a basis for building text-based chatbots. The company hopes the technology can be applied to complex reasoning problems in sectors such as cybersecurity incident response and industrial operations.

There's a commonly cited idea that water in a drain swirls in opposite directions in the Northern and Southern hemispheres. But is there any truth to it? When you pull the plug from a bathtub, does the water circle one way in New York and the other way in Sydney?

Although the idea is based on a real scientific principle, you probably won't see it play out in a small drain in your house, experts told Live Science.

The Coriolis effect

The idea that water spins in opposite directions in the Northern and Southern hemispheres stems from a phenomenon known as the Coriolis effect. When something, including air or water, moves across Earth as it rotates on its axis, that substance appears to curve because the ground beneath it is rotating at different speeds in different places. Points close to the equator move faster than points near the poles because they have a bigger circle to travel in the same 24 hours.

Over the immense distances covered by weather systems and ocean currents, that small deflection can accumulate and become important. The key words here are "immense distances." The Coriolis effect is weak, so it needs enough time and space to produce a noticeable change. Storms and weather patterns can persist for days and stretch across hundreds of miles. But water in a sink, bathtub or toilet has only seconds to move before disappearing down the drain.

"You always need to think about the right timescales and length scales," Susanne Horn, a professor of numerical and mathematical fluid dynamics at Coventry University in the U.K., told Live Science.

At your bathroom's scale, seemingly trivial details take control. The water may already be rotating slightly because of how it entered the basin, how somebody moved in the bath or how the plug was removed. The sink and drain are unlikely to be perfectly symmetrical, which can also play a part, and the design of a toilet deliberately guides its water. All of these factors are more influential on your basin than the Coriolis effect is. (In other words, that episode of "The Simpsons", which features Bart investigating drainage direction in Australia versus the U.S., got it wrong.)

Consequently, the same sink can drain clockwise on one occasion and counterclockwise on another, depending on the variation of these variables on any given day; the direction depends principally on how the water was introduced and the geometry of the container and drain, according to the Library of Congress.

So, although the Coriolis effect behind the claim is real, the water in a bathroom drain is normally overwhelmed by much stronger influences.

How to see the Coriolis effect in action

To make Earth's rotation ‪—‬ and, thus, the Coriolis effect ‪—‬ matter in a drainage experiment, Horn said, "there are essentially two tricks: let it drain very slowly, or make it much bigger."

Fluid dynamicists describe this using the Rossby number, which compares a flow's inertia with the influence of the planet's rotation. A small Rossby number indicates the Coriolis effect is important; a large one means the flow is moving too quickly or across too short of a distance, for Earth's rotation to have much influence. A typical household drain falls firmly into the latter category. In Horn's words, it "doesn't feel rotation."

Still, there are ways to see the Coriolis effect in action. In a meticulously designed experiment researchers suppressed those larger disturbances to give the Coriolis effect enough time to emerge.

In the 1962 experiment, described in the journal Nature, an MIT researcher used a large, carefully prepared tank that removed residual movements in the water before it drained. The water eventually developed the counterclockwise rotation predicted for the Northern Hemisphere.

Three years later, in another study published in Nature, researchers at the University of Sydney published a Southern Hemisphere counterpart. After taking similarly stringent precautions against outside disturbances, they observed the predicted clockwise rotation. The two experiments demonstrated that Earth's rotation could select the direction of a draining vortex — but only under extremely well-controlled conditions. In other words, the Coriolis effect appears only once you've removed practically every other variable.

That is very different from saying every sink or toilet flows in the same direction according to which hemisphere they're in. In normal plumbing, the drain's shape, the water's starting motion and the way it is released are all far more influential.

"Just ask yourself whether what you're looking at happens slower than Earth's rotation and for long enough, only then does the Coriolis force really start to matter," Horn said.

In 2013, MIT neuroscientists Steve Ramirez and Xu Liu published a paper detailing how they had created false memories in mice. They'd used optogenetics — where cells' activity is manipulated using light — to plant a fearful memory in the brain and then reactivate this memory with these pulses of light. The breakthrough helped to propel research in the field by showing that memories can be artificially constructed.

The initial experiments involved using a protein to tag brain cells in the hippocampus (a key memory center in the brain) that were active during the formation of a fearful memory. They then reactivated these "fear memory-bearing cells" while the mice were perfectly safe. The first four mice showed no response, but the fifth froze in fear. After analyzing the fifth mouse's brain, it turned out they had placed the protein in a slightly different location of the hippocampus to the others by accident — and inadvertently found the exact spot where the memory was stored — and that it could be manipulated and controlled.

In his book "How to Change a Memory: One Neuroscientist's Quest to Alter the Past" (Princeton University Press, 2025), Ramirez, now an associate professor at Boston University's Center for Memory and Brain,explores fundamental questions about memory: What is it, and can we manipulate it? He uses his personal experiences ‪—‬ including with loss, PTSD and addiction — to probe these ideas, asking whether this line of research could open new paths to treatments. He conceptualizes a world where memories could be manipulated to help ease a person's PTSD, or guard against dementia.

Live Science spoke with Ramirez about the book, the future of memory research, the ethics and implications for treating disease, and our brains' extraordinary power to recall our past. "How to Change a Memory" has been short-listed for the 2026 Royal Society Trivedi Science Book Prize.

"How to Change a Memory" excerpt: 'As if a shudder ran from its brain to its body': The neuroscientists that learned to control memories in rodents

Hannah Osborne: In the book, you reflect on your and Xu's major 2013 paper, noting that it was initially the result of a botched surgery in a single mouse. What if that little mistake hadn't happened?

Steve Ramirez: If we hadn't accidentally botched the surgery, I'd like to think we still would have gotten there, because what would have happened was that we would have done all the surgeries correctly, we would have hit the wrong spot, and everything would have been a negative result. And then, we would have said, "Maybe this is the wrong area to try to activate a memory." Now, where we would go next, I don't know.

I'd like to think that we would stay within the hippocampus and we would say, "Why not this other part or this other part?" Or maybe we would have moved to another brain area. But I think it would have delayed the inevitable by maybe six months or less.

Having hit the area, I think we realized that these mistakes — I shouldn't say mistakes; these unintended outcomes of an experiment — are certainly something that I think are pretty common. We just don't look for them often. A lot of times, we'll see a negative result and say, "OK, there's a million reasons why this experiment may not have worked as predicted," because it's very hard to touch base with reality and test the hypothesis. But I think it taught us to look a little bit more deeply when we see results that are either confusing or head-scratching.

The more I talk to people in science, I think everyone has this version of this one hiccup in an experiment [that] led us down a completely different rabbit hole that ended up being the basis of a paper or a series of papers ‪—‬ or, in mine and Xu's case, a career and then some.

I wouldn't say that they're universally common in every experiment, but I think that biology is so squishy, we're going to get things that kind of zig when we think that they're going to zag.

HO: Throughout the book, you talk about engrams. What are they, and why are they so important to memory research?

SR: An engram is a theoretical construct. It's a theoretical topic that certainly elicits every possible opinion out of memory researchers because it's kind of the holy grail of "what is memory." We think of an engram as whatever the physical basis of memory is.

It's almost like, what are the cellular building blocks of a memory in the brain? Whatever those building blocks are, that's what we consider an engram. And the reason I say that it's theoretical is because we don't really have a clean-cut "This is where an engram begins and ends in the brain."

We're not at the point where we have a Google Maps for an engram and we can zoom in to "This is the emotional part, and this is the smell associated with the memory." We have more of a zoomed-out satellite view of what an engram looks like. But we'll get there, and it's important, because if we have a full understanding of the physical manifestation of memory in the brain, then we have a way better chance of predicting what's going to happen when those building blocks break down and give rise to certain kinds of amnesia or cognitive impairments or memory loss.

By analogy, we have a pretty good understanding of how the heart works down to the physics of how a pump works, for example. Now that, thankfully, has enabled us over the past 200-plus years of cardiology, to have heart valves that we could 3D print or grow in pigs or things like that. With the brain, there's no law of physics saying that we can't get there to turn the brain into how we view the heart, where we can 3D print pieces to replace what was broken, or we understand a bit of clogging in this artery will lead to all of these different impairments.

We're only beginning to understand what those [metaphorical] clogged arteries look like in the brain, especially when it comes to memory. So if we have an understanding of the detailed physical picture of what an engram is, then we'll have a better shot of being able to predict what happens to ideally even prevent its breakdown, for example.

The goal is to understand the physical basis of memory and to use that understanding to try to enable well-being to an individual.

HO: In your experiments, you've used optogenetics to manipulate memories in mice, but that technique isn't widely used in human medicine yet. If you wanted to apply it in humans as a therapy, are there hurdles we'd need to get over? How are we going to be thinking about changing memories in 10 years?

SR: I'm so glad you asked, because I think it can go in two directions. Optogenetics is not really used in humans at all, except for maybe like eye retinal therapy, because you can flash light into the eyes and it's noninvasive and pretty straightforward. [Editor's note: Optogenetic retinal therapies are currently in clinical trials.]

There are groups working on some pretty remarkable technologies on being able to deliver [genetic] payloads into the brain, such as an optogenetic tool, but in a way that doesn't even require putting a virus in the brain [as is often done in gene therapies] or the optic fiber. There's groups working on giving even injections peripherally — like in the arm or in the rodent tail — and have that make its way into the brain, so it's way less invasive.

I'd like to think that technologically, we [researchers in the field] are working on trying to get optogenetic tools as noninvasively in humans as possible. But maybe the question becomes, do we want to do optogenetics in humans? And I just think that we may not have to, because there's so many other ways of doing what optogenetics does in rodents in humans, but especially with regards to memory.

In rodents, we have to go in and find those cells that hold on to a particular memory, that part of an engram, and activate those cells to get the animals to recall the memory. In humans, I can just ask you, "How was your night last night? How was your dinner? Did you have anything particularly savory or sweet?" Then, just through noninvasive verbal communication, a world of memory can come back in your mind.

I'd like to think of what we're doing in rodents as setting a blueprint for the kind of work that we could do in humans and that we can be clever about how to access things like memories in humans, where invasiveness like deep brain stimulation or transcranial magnetic stimulation is probably a last line of defense, whereas maybe the first lines of defense would be more cognitive behavioral [therapy, or CBT] because it requires no invasiveness into the brain at all.

HO: You look at the ethics around memory research a lot in the book. Where do you think the line is for whether we can apply memory manipulation, versus whether we should?

SR: I think there's two things happening simultaneously here. I don't think we should ever, for example, remove personal agency from the decision-making process here unless our personal agency has been removed by a particular disorder or something that can be medically considered [as having] robbed us of our ability to do the things that we want to do.

For instance, a patient living with depression, we may not just be able to tell them, "Think positive memories." Well, no, that's the very thing that we can't do, right? It's like asking someone with a broken leg to walk it off. So I think of it this way, where this kind of work can go with humans: we have to have some morally or ethically bounded goal of why we're doing what we're doing.

The goal of our research is truly to understand memory and to use that understanding to restore health and well-being to an individual. Now that's pretty arbitrary. That's human-made. We've made that up. We're the ones that made up this ethical boundary that this has to be used as a force for good — but by having that either ethically, or morally, or even medically bound goal, it can prevent us from derailing because we have a goal in sight that considers the overall well-being of people.

This is kind of like a sinister example, because people have compared this to the Manhattan Project. The goal was to build the bomb — it was to build or use nuclear fission; create it so that we can create a bomb. Now that's not necessarily an ethically bounded goal. The goal there is "win a war," and it's kind of the opposite of how I think about our research. The goal of our research is to prevent misuse by anticipating it first.

So what are the seat belts and what are the guardrails here? If we start by considering memory manipulation as part of our tool kit to help tackle disorders of the brain, then we have to use that inherently into some sense of good or medical good.

If we keep memory manipulation in the province of medicine, and in the clinic, then we can at least start in a way that takes the person into consideration first and foremost. We can study it to see, what are the side effects? Just like with any other drug, long-term use, is there desensitization? Are there clinics popping up everywhere that's doing this underground? We can anticipate all of this, right? Begin with it in the clinic, because we can have a kind of social infrastructure that can prevent its misuse and really hit the accelerator on using it for good.

The second part — and where I take my academic hat off and just become part of the public like everyone else — is, it's on us, society as a whole, to at least engage with some semblance of science literacy in a way that I think science can really be conveyed and used for good, whether it's storytelling or as a tool. Right now, it's so easy to fall under the traps of misinformation.

When we think of memory manipulation, everyone thinks Hollywood: "Eternal Sunshine [of the Spotless Mind]," "Total Recall." That's good for getting the conversation started and saying, what did "Total Recall" get right and wrong? What did "Eternal Sunshine" get right and wrong? But let's look at Hollywood, and let's use it as a case study of, where did memory manipulation go wrong here? Let's avoid that, or let's try to come up with some infrastructure that can avoid it. Where did memory manipulation go right? Let's try to do more of that and build some infrastructure around that.

HO: In the book, you note neuroscience is a relatively young discipline compared to things like astronomy. What do you think is the weirdest and most mind-blowing thing about memory that we still don't understand?

SR: The first thing that comes to mind is — I don't know how many memories we have, but let's just say we have a million memories or 10 million memories — that it's amazing to me that if I had 10 million memories, they all exist in my brain right now. They're all there. I can randomly think of the last time I ate steak, and my steak memories come up. Or I can randomly think of the last time I played a song on the piano, or me and Maple [his dog] going out for a walk, and then all of those memories come back.

So, 9,999,999 memories are quiet right now in my brain, except for one, which is me going out for a walk with Maple yesterday. But presumably, the other memories are still shaping me and sculpting my brain and influencing very much my biology, my sense of self, my personality, my identity, because they are me. They're just not bubbling into consciousness at the moment.

I think it's amazing that I can recall one memory and on the basis of what that memory is, I can either be moved to euphoria because I'm thinking of some of the happiest days of my life or be moved to tears because I'm thinking of more somber days of my life. And both of those can happen within like five seconds or less, depending on which memory I chose. I can experience the peaks of happiness or the valleys of sadness within five seconds or less. It's crazy that we can do that without really breaking a sweat.

What is everything else [the other memories] doing simultaneously? They might be helping to sculpt things like our imagination or our dreaming or our sense of self, which is an aggregate of all the sum of all of our experiences. I think that the fact that memories can move us through the entire landscape of emotion within seconds and that we have so many more memories that just fly under the radar of consciousness that are probably doing that and more is pretty remarkable. It's kind of scary, but it's kind of remarkable to think about it that way.

HO: On a related note, why do we wake at 3 a.m. and think of something stupid we did 20 years ago?

SR: As someone that wakes up like every other night at 3 a.m., I totally resonate here. There's a couple of theories. The first is less of a theory and more of a point. In terms of like the previous question about how remarkable memory can be, it's amazing that we have dormant memories that are decades old that, up until right now, we have every reason to believe we'd forgotten them. They don't exist anymore ‪—‬ out of sight, out of mind ‪—‬ and they're off into the ether now. But the fact that we can wake up at 3 a.m. and randomly remember something from 20 years ago is beautiful evidence that memories might go into dormancy for decades, but they may not actually be gone or erased or forgotten.

It's kind of wild, because I think that we have more possible connections in our brain than we do seconds of life. I don't think we would ever run out of space in our brain. I don't think that would ever happen.

But in terms of like waking up and the kinds of memory or waking up and recalling memories from the distant past, one theory is that whatever was happening when we formed that memory, there were particular sights and sounds and smells happening around us, and presumably we also felt a particular way during the formation of that memory, like our inner state was something when we were making that memory. Probably through random chance, when we wake up …our inner state happens to match the state that we were in when we made that memory, plus maybe a couple of more cues ‪—‬ a random song in the background that was playing that reminds us of it, or a particular odor, or maybe even something subtle like we saw a commercial an hour ago that just primed that.

I think it's evidence that some memories may truly live on in the brain for the entire life of a person, even though we don't recall them for decades, meaning we have access to an insane amount of memories in the brain that we don't always actually intentionally access.

We don't have an answer for it yet, but it gives me hope that some memories that are thought to be gone are not and actually way more restorable.

Hannah Osborne: It's a very personal and moving book, which you dedicated to Xu Liu, who passed away in 2015. What made you want to write it, and was it a difficult process?

Steve Ramirez: There's two things that made me want to write this book. The long-term reason was because I've always wanted to write a book since I was a kid. I do think that there's this inner 5-year-old core of me that thinks that if you're on a bookshelf, you matter somehow, like you did something that was important that all of humanity can read and presumably benefit from or learn from in some way, and I always found that cool as a kid.

More personally, in 2015, a book agent had reached out, asking if I was interested in writing a book. And I said, "Absolutely — but I have no idea about what." It wasn't until Xu passed away that all of the puzzle pieces clicked, [and] I was like, "I know what I want to write about" because I now have a real passion project. I knew that I always wanted to intertwine a bit of myself in this project because that's the way that I teach. In the classroom, I often bring my lived experiences.

More than anything, it was a way of honoring my friend, and that really felt like the purpose of the book — to honor my friend and, along the way, teach neuroscience, because that was kind of the basis of our friendship to begin with. I realized it's not so much that I want to as much as I have to write this book. That turned into very much benefiting from it in all of the weird ways that writing a book can change a person.

HO: Could you tell me about how you and Xu met and when your friendship clicked?

SR: Our friendship really did click on the first day that we met. We met in the lab, so we knew that science was going to be the common denominator of conversation, but it just so happened that there was a social that day for our building, which just meant free food and drinks for everybody. When we started chatting, we said, "Let's go; let's not miss the free drinks and food. Let's go to the social, and we'll continue our conversation there."

Then we spent the next couple of hours talking about all of these ideas of trying to artificially reactivate memories and why we thought they were important. It was such an easy conversation to have because I felt like I could let my academic guard down around him because, at least in the first year of grad school for me, it felt very stuffy and everyone at MIT was like an insane hotshot in some way and very intimidating. But Xu was just someone that I could level with; I could ask my quote unquote dumb questions, and I could just have a regular conversation about science.

When we were in the elevator ride back up to the lab, he mentioned just in passing that since it looks like we might be working together, we should just be co-first authors on everything that we do. It was just so perfectly emblematic of how our friendship would evolve, where all of our talks, all of our presentations, even awards, we were very like down the middle because there was no one without the other when it came to how we did our projects together. The combination of the scientific and the interpersonal made it easy. We were quite different people but very complementary, and I think that's what made it work.

This interview has been condensed and edited lightly for clarity.

The tiny, now-extinct human relative known as a hobbit had an even more human-like body than previously thought, and probably walked upright somewhat slowly, anthropologists have discovered by studying their hip bones.

But with a more primitive walking style than modern humans and lack of hunting and cooking, the species still differs significantly from Homo sapiens — so with the new findings, the mystery of the hobbits' origins has only deepened.

"Based on just the hip bones, Homo floresiensis looks generally like humans and other genus Homo species and probably could have moved a lot like humans," Kristi Lewton, a biological anthropologist at the University of Southern California, told Live Science. But H. floresiensis "was not a particularly fast biped and was not traveling long distances," she said.

Lewton and colleagues closely studied the pelvic bones of LB 1, an adult female hobbit who was about 3.5 feet (1 meter) tall when she died between 100,000 and 60,000 years ago on the Indonesian island of Flores. They looked for clues as to whether members of H. floresiensis were more similar to other Pleistocene human species or to earlier australopithecine species, such as the iconic "Lucy". Their study was published Aug. 25 in the American Journal of Biological Anthropology.

Ever since H. floresiensis was discovered in 2003, researchers have tried to figure out why members of this species were so small and which species they evolved from. The hobbits' skeletons have a unique mixture of human-like and australopithecine-like traits, making assessment of their evolutionary ancestry challenging. For instance, the hobbits' hand bones are more similar to those found in australopithecines, but their shoulders and upper arms are more human-like.

One physical characteristic that experts have identified in H. floresiensis is known as iliac flare, or the degree to which the hip bones are flared out from the center of the trunk. A large degree of iliac flare has been linked to australopithecine anatomy and, functionally, to less efficient bipedal walking than is seen in humans. But a problem that Lewton and colleagues encountered was that different methods used to quantify the "iliac flare" of humans' relatives often produced contradictory results.

In their new study, the researchers compared hip bones from chimpanzees, gorillas, australopithecines, and both living and extinct human species. By creating a quantifiable measure of iliac flare and adding other measurements of the pelvises of these species, the researchers found that the pelvis of LB 1 was statistically similar to other Pleistocene human species, such as Homo erectus, and different from australopithecines and apes.

"These results suggest that H. floresiensis likely used a form of bipedal walking that would have been markedly similar to those of humans," the researchers wrote in the study.

But the similarity of the hobbit pelvis to other human groups does not mean that their form of bipedalism was exactly the same as ours. Rather, their bones suggest the hobbits were a species "that was not traveling long distances or at fast speeds and that may have incorporated some arboreal behaviors," the researchers wrote in the study.

Caley Orr, a paleoanthropologist at the University of Colorado Denver who was not involved in the study, said "their results are consistent with a more limited quantitative comparison among fossil pelvises that my team published last year." In that work, the LB 1 pelvis also popped out as being mostly human-like, Orr told Live Science.

The new results suggest that there is considerable variability in the size and shape of the skeletons of early human groups, he added, but "what this means for the origins of the 'hobbits' remains ambiguous."

Although Lewton and colleagues focused closely on just one part of the hobbit skeleton, they noted that their results support the two main theories of how these mysterious humans evolved.

"Most evidence points to one of the two following hypotheses," Lewton said. "Either H. floresiensis evolved from a population of H. erectus that arrived on the island of Flores and experienced insular dwarfism, or H. floresiensis derived from a small-bodied, earlier radiation of a different species of Pleistocene Homo." In other words, they may have been H. erectus that shrank over time because they lived on an island, or may have evolved from a smaller, unknown Homo species.

Genetic analyses, including studies of ancient proteins, could potentially help experts resolve the question of where hobbits came from, Lewton said. "But this question is probably not going to be resolved any time soon."

See how much you know about early humans with our human evolution quiz!

There are many theories as to how the diabetes drug metformin lowers blood sugar levels, but now, scientists think they've discovered the main route.

It turns out that the drug, primarily used in type 2 diabetes, forces gut cells to absorb and burn extra glucose. It achieves this by messing with gut cells' mitochondria — their internal power generators.

Although metformin was first used in patients in the 1990s, scientists have been unsure of how it works.

"Every year there's a new mechanism for metformin that says last year's mechanism was wrong," said study co-author Navdeep Chandel, a biochemist at Northwestern University.

Part of the problem is that metformin affects several organs. "Metformin has a complex mechanism of action, with effects in several organs and on different aspects of metabolism, making it difficult to identify a single mechanism that explains all of its effects," Manuel Vázquez Carrera, a pharmacology researcher at the Sant Joan de Déu Research Institute who was not involved with the study, told Live Science in an email.

Some studies suggested that metformin causes intestinal cells to use up glucose, and an animal study released last year proposed that the drug causes glucose to move from the bloodstream into the intestines, where gut bacteria can then break it down. Other research pointed to the liver, proposing that the drug lowers blood glucose levels by inhibiting gluconeogenesis, a process in which the liver makes glucose from other molecules, usually to regulate sugar levels during fasting or exercise.

The scientists exploring the drug's action in the liver found that metformin interacts with a large complex of proteins inside mitochondria. Called mitochondrial complex I, it's a key player in generating cells' primary energy currency: the molecule adenosine triphosphate (ATP).

However, the theory that metformin mainly works by targeting this complex was quickly dismissed. That's because the drug's concentration in the liver is too low to exert an effect, Vázquez Carrera said.

But elsewhere in the body, it's a different story. In the recent study, published in May in the journal Nature Metabolism, Chandel and his colleagues found that metformin does work by targeting mitochondrial complex I — but it does so not in the liver but in the intestines, where the drug builds up to higher concentrations.

Their first clue came when they compared metabolites in the bloodstreams of people taking metformin and those unexposed to the drug. For one metabolite, called citrulline, they saw the biggest drop in concentration following a dose of metformin. This blood metabolite is produced almost exclusively by mitochondria in intestinal cells, revealing that the drug affects gut mitochondria.

In further experiments, the team genetically modified mice so they had a backup for complex I in the intestines. The backup was a different enzyme that performs a similar function but is not affected by metformin. That meant that if the drug works by inhibiting complex I, mice equipped with backups could bypass the drug's effects. When the researchers administered metformin to these mice, they found that the drug was much less effective at lowering citrulline levels in the blood, suggesting that metformin acts on complex I in intestinal cells.

Besides affecting citrulline, the genetic tweak also reduced metformin's effects on blood sugar by 80%, Chandel said. This means inhibition of complex I is probably the main mechanism behind the acute effects of the drug, he added.

Mitochondria can generate roughly 30 ATP molecules from one glucose molecule, but when these powerhouses are blocked, the cell tries to compensate by running a less-efficient ATP production line. This alternate pathway, called glycolysis, generates only two ATP molecules per glucose molecule. The researchers argued that by inhibiting intestinal mitochondria, metformin might force the cells to sequester and burn through as much glucose as possible with this less-efficient strategy. In turn, that lowers blood sugar levels.

They were able to show this in lab mice. Metformin caused glucose to accumulate in intestinal cells of normal mice, not the mice carrying backup enzymes, suggesting that the cells with blocked-up mitochondria usurp hoards of glucose to run glycolysis instead.

"Much of the mechanistic evidence comes from male mice, so it remains unclear how well the findings translate to humans and whether there are sex-specific effects," Vázquez Carrera noted.

Most of metformin's sugar-lowering activity — about 80% — involved complex I, but it's likely that the drug has additional targets. In future work, Chandel and his colleagues aim to explore how the drug affects other aspects of the body's biology, such as the liver or the gut microbiome.

This article is for informational purposes only and is not meant to offer medical advice.

Twenty-nine state attorneys general went into an Oakland, California courtroom this month seeking roughly $200 billion from Meta over claims of teen addiction. Their case ended in its second week, with a settlement agreement that requires Meta to pay up to $17 billion across 10 years and make several product changes, such as a midnight-to-6 a.m. blackout, a two-hour daily cap, and an optional chronological feed. While some of these requirements are steps in the right direction, the settlement gives the company too many ways to avoid making meaningful, lasting changes to their products. The agreement is time-limited, relies on Meta's definitions of critical terms, and doesn't require detailed disclosure to the public.

What makes this settlement worthy of attention is the deal's requirement for an independent auditor, which is the first time anyone examining Meta's product design will be chosen by someone other than the company. Independent regulators, such as the Federal Communications Commission, are a proven (if imperfect) way to protect the public interest, and social media platforms are now at least as important to our lives (and our children's lives) as the broadcast and telecom industries that the FCC regulates.

Under the agreement, an independent auditor will have access to Meta's internal data and engineers, a mandate to report annually on whether the company is doing what it promised, and an obligation to make a summary of each report public.

On the surface, this is good news. But look a little deeper and it becomes clear the auditor's power is too limited. First, the agreement repeatedly defers to Meta's current business practices, rather than defining new standards based on the public interest. For example, Age Appropriate Experiences are defined as "content captured in Meta's applicable Ages 13+ content setting." Harmful Experiences are defined as "behaviors that violate Meta's Community Standards," and age verification data must only be protected "using Meta's highest data privacy and security standards." This creates myriad openings for clever Meta employees to meet the letter of the agreement while avoiding real change.

Second, the auditor's public report will be heavily redacted. The summary will describe the status of Meta's implementation of the agreement for the period, and whether Meta adopted or agreed to adopt the auditor's recommendations. But it allows Meta to exclude information that it deems "nonpublic, proprietary, or Confidential." Given that one of the core issues of this case was Meta burying unfavorable data, this is deeply concerning.

This limited public disclosure is insufficient for external researchers and the public interest. Meta says in its public announcement of the settlement that the agreement includes the establishment of "an independent social media research foundation" with which "Meta will share consented user data… to advance independent research into teen well-being" — but we could find no mention of this foundation as an obligation in the settlement.

Finally, the requirement for an independent auditor expires in as little as five years (the agreement itself expires after 10 years). This creates an incentive for Meta to run down the clock until it can return to business as usual, rather than making permanent changes.

We do not mean to suggest this agreement is not a positive step. Its weaknesses are not failures of negotiation, but rather a reflection of the limits of a legal settlement: a bargain with one company, for a fixed period, based on specific legal claims at the time of agreement.

That's why legislators urgently need to act now. A new law, preferably at the federal level, should convert the independent auditor into a strong, permanent regulatory oversight body, funded with annual fees on big tech companies in proportion to the size of their business and impact on society.

A permanent regulator could also go beyond one-time agreements on specific Meta features, and build an ongoing body of research and practice around safety best practices. This would allow society to develop its own definitions and standard of care that could apply internet-wide. A more comprehensive approach to regulating social media, looking beyond issues of child safety on specific platforms, is needed.

There's a particular need for the public to have more insight and control over how social media feeds are constructed. The agreement requires Meta to offer teens the option of choosing a non-personalized (and thus presumably less addictive) "home" feed, but doesn’t make this the default, and still lets teens continue to use the personalized feed. Since research has shown most people dislike chronological feeds, this requirement will probably have limited real-world impact.

Further, the provisions establish that the non-personalized feed will consist of "content [that] is populated by accounts the Teen User follows or has friended, displayed in chronological order." This assumes that a chronological feed is the best alternative to Meta's curated feed. There is an argument that well-designed algorithms could actually contribute to improved mental health if optimized to deprioritize toxic posts and misinformation, while aligning with users' preferences as to what gives them long-term value.

We also urgently need independent, rigorous audit standards for privacy and security of online identity data. Trusting the same company that gave us the Cambridge Analytica scandal to grade their own homework on this front is a bad bet.

We hope that this settlement agreement will become a baseline, not a high water mark, for more thoughtful regulation of internet platforms. This case, and the many other pending lawsuits in state and federal courts, are useful in providing evidentiary material, political attention, and specific concessions. But they are not substitutes for the durable rules and institutions that only Congress and state legislatures can provide.

Editor's Note: This opinion piece was jointly published on Friday Aug. 28 in Jonathan Bellack's free weekly newsletter, Platformocracy, which advocates for more democracy in our online lives.

This article is for informational purposes only and is not meant to offer medical advice.

Opinion on Live Science gives you insight on the most important issues in science that affect you and the world around you today, written by experts and leading scientists in their field.

Scientists may have found a way to regenerate the neurons that are lost due to conditions like Alzheimer's disease, a new laboratory study hints.

The research, published Aug. 26 in the journal Cell Biomaterials, suggests that reducing levels of a key protein in another type of cell in the brain, called astrocytes, may convert those cells into neurons. The adult brain has a limited capacity to produce new neurons, at baseline, and an even more limited ability to replace neurons lost to disease.

If successfully developed into a treatment for humans, this new approach could replenish lost neurons and thus restore brain function, the study authors say.

Astrocytes are abundant, star-shaped cells in the brain that protect and support the functions of neurons. A crucial protein for astrocyte development is called PTBP1, and previously, scientists suggested that eliminating this protein in astrocytes may convert them into neurons. In that study, researchers reported converting astrocytes in the mouse brain into neurons by eliminating the gene that coded for PTBP1.

However, later experiments contradicted these results, suggesting that newly formed neurons could not be traced back to the astrocytes. So Peisheng Xu, a co-author of the new study and a pharmaceutical scientist at the University of South Carolina, set out to investigate that contradiction.

"We felt it's strange [that] two groups of people got different conclusions," he told Live Science.

He used a technique called Nano-Eraser, developed earlier in his lab, to delete PTBP1 from astrocytes without editing any of their genes. The team accomplished this by packaging an antibody that targets PTBP1 into a polymer gel. That gel helped sneak the antibody across the blood-brain barrier, a gatekeeper that prevents certain substances in the bloodstream from entering the brain.

Once it reaches astrocytes in the brain, the antibody binds to PTBP1 and drives the cell's internal machinery to destroy the protein.

"I think it's quite interesting, intriguing and an innovative approach," said Dr. Christiane Wrann, a neuroscientist at Harvard Medical School, who was not involved in the study. "They show that [the gel] can cross the blood-brain barrier," which is important for developing therapies for the brain, she told Live Science.

The team first tested the gel in human astrocytes grown in lab dishes. Over the course of days, astrocytes exposed to the gel lost their characteristic star shape and started to form axons — the wires from which neurons send messages. Proteins typically found in neurons also became more abundant in the astrocytes.

The cells later showed electrical activity that further confirmed that they were functioning similarly to neurons and could fire synchronously. The gel also showed similar results in miniature models of the brain, called organoids, which had been grown from human stem cells.

The researchers then tested the gel in mouse models of Alzheimer's disease. These lab mice had lost neurons and had developed some characteristic features of Alzheimer's disease, such as inflammation, loss of cognitive function, and sticky clumps of a protein in the brain.

The team gave these mice two intravenous doses of the gel, eight days apart. Over the next four weeks, behavioral tests suggested that the treated mice's memories improved and they were able to build better nests than untreated mice; that's an indication of improved behavioral function. Later, the researchers examined the brains of the treated mice, finding that the density of their neurons had increased while their levels of inflammatory molecules decreased.

However, while the lab-dish experiments indicated that astrocytes converted into neurons, that finding has not been confirmed in live mice, Xu said.

"We observed that neuron density increased in treated mice compared to untreated ones," he said, "but we cannot yet eliminate the possibility that some other neural stem cells might have also converted into neurons."

Wrann agrees that additional experiments would have been required to see whether a particular astrocyte in the mouse brain changed into a neuron. While the results are "intriguing," a lot more research is needed to see the long-term effects of such a treatment on different types of brain cells, she said.

Xu and his team now plan to probe further into astrocyte conversion in live mice. Before they can move to clinical trials with people, he said, the safety and effectiveness of the treatment would need to be tested in nonhuman primates.

Notably, astrocytes themselves serve important functions in the brain. So there's a question about what having "chronically reduced PTBP1 could do to the brain," Wrann noted. She agreed that careful studies would be needed for this to translate to humans.

"That's something that needs to be tested step by step," she said.

See how much you know about the most complex organ in the human body with our brain quiz!

Scientists have uncovered an ancient shark "graveyard" in the middle of the Egyptian desert.

Fossilized teeth from seven shark species dating back millions of years were discovered in the Abu-Tartur Plateau ‪—‬ located in Egypt's Western Desert ‪—‬ between 2020 and 2022, offering new insight into the desert's watery past. The researchers detailed their discovery in a study published Aug. 18 in the journal Cretaceous Research

"This study provides evidence that the area now occupied by the plateau was once a sea with flourished marine life, with environmental conditions suitable for its development and prosperity, including favourable temperatures, sunlight, and appropriate oxygen levels," study first author Tarek Yassin, a paleontologist at Cairo University in Egypt, told Live Science in an email.

During the Cretaceous period (145 million to 66 million years ago), temperatures on Earth were generally warmer than they are today, with sea levels up to 558 feet (170 meters) higher than they are now, according to the Natural History Museum in London. As a result, shallow seas formed in areas that are now fairly dry, including the Egyptian desert.

The Abu-Tartur Plateau lies along the Duwi Formation, a Late Cretaceous geological rock formation that spans Egypt's Eastern and Western deserts. Previous research had already uncovered fossils of fish, sea turtles and other marine reptiles in this region, hinting at the thriving ocean ecosystem that once existed there. The rocks are also rich in phosphorite, a type of sedimentary rock that often forms from the shells and bones of marine animals.

"We had conducted research before our expedition and knew that areas rich in phosphate deposits could also contain fossils of vertebrate marine organisms," Yassin said, adding that finding the shark fossils was an "exciting surprise."

Yassin and colleagues had previously found fossilized teeth from two types of mackerel shark, but further expeditions between 2020 and 2022 uncovered 14 more fossilized teeth belonging to at least five additional shark species. One of these species, Scapanorhynchus raphiodon, an ancient relative of present-day goblin sharks (Mitsukurina owstoni), had never been reported in Africa before. Another two,Serratolamna serrata and Squalicorax bassanii, had never been seen in Egypt.

"Finding teeth belonging to seven different shark species was particularly remarkable, especially because they were all discovered in the same location, in the middle of an entire plateau," Yassin said. "This discovery is more than simply a large assemblage of shark fossils."

The existence of so many shark species in the same area suggests it was once home to a nutrient-rich, complex ecosystem, with plenty of smaller fish to feed these apex predators. However, the discovery doesn't necessarily mean these sharks coexisted; rather, their remains may have become jumbled together in the same sediment over time, the study authors noted.

The team plans to continue their research in the Abu-Tartur Plateau and explore the surrounding area. "We believe there is still much more to discover," Yassin said.

How much of a shark fan are you? Find out with our shark quiz!

Climate change is making El Niño stronger and more dangerous than ever before, scientists warn.

In a new study, researchers have revealed that El Niño events have become nearly 40% stronger over the past four decades than they were in the preindustrial era.

The finding comes as the world is in the grips of a historic "super" El Niño. While daily average sea surface temperatures soar to unprecedented highs, forecasters have become almost certain that the 2026 to 2027 El Niño will be an all-time record event.

"We don't see a time in the past where El Niños have been as strong as today, and we show that the strength of El Niño changes in parallel with the warming of global temperature," study first author Julia Cole, a professor and chair of the Department of Earth and Environmental Sciences at the University of Michigan, said in a statement. "Our findings tell us that the big El Niño events of the last 40 years are not normal in the context of the last thousand years."

El Niño events occur every two to seven years as part of the Pacific Ocean's El Niño-Southern Oscillation (ENSO) natural climate cycle. The ENSO cycle flips between the warmer El Niño phase and the cooler La Niña phase, with neutral periods in between.

El Niño periods bring elevated sea surface temperatures in the central and eastern Pacific, thereby weakening or reversing trade winds and strongly disrupting global temperatures and rainfall patterns. Earth's last El Niño ran from June 2023 to April 2024, delivering an injection of heat to our already warming world that made 2024 the hottest year on record.

The impacts of El Niño periods can be profound, with studies linking the events to famine in Europe, civil wars in tropical regions, and droughts, floods and forest fires around the world.

Climate scientists have long suspected a link between the growing intensity of recent El Niño events and global warming. But sparse instrumental records and significant variability in the natural climate pattern has made it difficult to say so for certain.

So in the new study published Aug. 27 in the journal Science, researchers investigated whether climate change has been boosting the severity of recent El Niño events. The team analyzed 13 ancient and modern corals taken from close to the events' epicenter — the Pacific Ocean's Galápagos Islands.

By analyzing the temperature-sensitive chemistry of the coral samples, the scientists discovered a millennium-spanning pattern of lower intensity El Niño events being gradually superseded by ones of increased strength after humanity's widespread adoption of fossil fuels in the 19th century. Using climate simulations, the researchers ruled out the possibility that natural causes, such as volcanic eruptions or solar variability, could have caused this shift.

"We kept adding records thinking well, this is going to get more complicated, but it really didn't," Cole said. "This is such a clear story."

The prospect of El Niño and climate change feeding back into each other is troubling, the researchers said, especially as the climate pattern has the potential to drive persistent shifts in major ecosystems such as the Amazon rainforest.

"El Niño is a really big source of climate extremes, and so if it's getting stronger, the impacts are getting stronger. Impacts like droughts, floods, wildfire and food insecurity," Cole said.

In the short term, the combination of climate change and El Niño could bring significant strain to our warming planet.

"The question is not whether the current El Niño is going to happen, but how bad is it going to be, and how bad will the impacts be?" Cole said. "This event is superimposed on global warming, and it's likely to supercharge the temperature increase that we would normally see from greenhouse gases."

The findings further underscore the urgent need to mitigate further global warming, Cole noted.

"No country has the resources to be fully protected from these impacts. This is one more reason we need to move away from fossil fuels, the root cause of the problem," Cole said.

NASA's next-generation cosmic observatory — the Nancy Grace Roman Space Telescope — is set to launch this weekend on a potentially decade-long mission to hunt for distant exoplanets, map out the Milky Way and unravel some of the universe's biggest mysteries, such as the true nature of dark matter.

The Roman telescope and its payload are scheduled to lift off aboard a SpaceX Falcon Heavy rocket Sunday (Aug. 30) at 7:26 a.m. EDT from Launch Complex 39A at NASA's Kennedy Space Center in Florida, according to NASA. A few hours later, the telescope will be released from the rocket's second stage and be exposed to the vacuum of space for the first time.

But even if everything goes according to plan, we will still have to wait a while to get a glimpse of Roman's first groundbreaking images.

As of Thursday morning (Aug. 27), the National Weather Service forecasts a 50% chance of thunderstorms at Kennedy Space Center Sunday, so weather could delay the launch. If that happens, a second launch window is available Monday (Aug. 31) at 7:22 a.m. EDT, when there is a reduced risk of thunderstorms.

You can watch the event on a SpaceX livestream and stay up to date with last-minute developments and postlaunch news via a live blog from Live Science's sister site Space.com.

What is the Roman Space Telescope?

The Roman Space Telescope is NASA's latest flagship observatory. It follows the James Webb Space Telescope (JWST), which launched in 2021, and the Hubble Space Telescope, which has been in orbit since 1990. Rather than replacing those spacecraft, Roman will work alongside them to help scientists scour the skies like never before.

The observatory is named after pioneering scientist Nancy Grace Roman, who served as NASA's first chief astronomer between 1960 and 1979. It is approximately 42 feet (12.7 meters) tall and 14 feet (4.4 m) wide and weighs around 18,000 pounds (8,000 kilograms) — about the same as a fully grown Tyrannosaurus rex, according to a NASA fact sheet.

Roman was fully completed in December 2025, almost a decade after construction began and within its initial $4.3 billion budget (less than half what JWST cost). Since then, it has been moved more than 900 miles (1,450 kilometers) from Goddard Space Flight Center in Maryland and undergone a series of final checks in NASA's "clean rooms." Having initially been slated for a 2027 liftoff, the telescope is technically launching ahead of schedule.

Roman will eventually be stationed around 1 million miles (1.6 million km) from Earth at what scientists call a Lagrange point — a fixed point relative to our planet where the gravity of two objects cancels out. Its specific Lagrange point will be Sun-Earth L2, where JWST and the European Space Agency's Gaia and Euclid space telescopes already reside.

Roman's initial mission will last five years, but experts hope it could survive at least twice that long. Some space telescopes far outlast their initial missions; for example, Hubble is more than two decades past its original mission parameters, and NASA's recently doomed Swift Observatory lasted 10 times longer than predicted.

What makes Roman special?

Roman has two key instruments that set it apart from its predecessors. The first is its Wide Field Instrument, a 288-megapixel camera attached to a 7.9-foot (2.4 meters) mirror, which gives it a field of view 100,000 times greater than Hubble's. It will also see the cosmos in infrared light, similar to JWST. These combined capabilities will allow Roman to observe the cosmos like never before.

But the telescope's secret weapon is arguably its coronagraph, which can block out the light from distant stars, allowing Roman to see fainter objects, such as the exoplanets that orbit these stars. Until now, scientists' main way of finding alien worlds was to wait for them to pass in front of, or transit, their home star, but Roman will be able to directly image exoplanets at almost any time in their orbital cycles. (Exoplanets remain out of view when they are directly behind their home stars.)

One of the biggest and most exciting claims researchers have made about Roman is that it could help reveal up to 100,000 exoplanets. Such discoveries would revolutionize how we study alien worlds, especially considering that we have uncovered over 6,000 exoplanets since the first one was spotted in 1992.

However, the telescope will also conduct long-term surveys that will help astronomers accurately map the Milky Way and find extremely distant galaxies, potentially helping scientists solve the mysteries of dark matter and dark energy that currently underpin a "cosmological crisis" surrounding the universe's expansion. And as with any new space telescope, scientists will likely find novel ways of using Roman once it is in operation.

"The mission will offer practically limitless opportunities for astronomers to conduct a broad range of additional science," NASA representatives wrote in the fact sheet. "From objects in our outer solar system and exploding stars to growing black holes and galaxies by the billions, very little will be beyond Roman's reach."

The spacecraft will beam roughly 1.4 terabytes of data — roughly 10 times the storage capacity of an average smartphone — to ground stations across Earth every day, according to the fact sheet.

When will we see Roman's first photos?

Roman's first snaps are arguably the most anticipated astronomical images since the debut photos from the ground-based Vera C. Rubin Observatory, which were released in June 2025.

But first, Roman has to travel to its Lagrange point, which is roughly four times farther away than the moon. This could take several weeks, although no exact timeline has been provided.

Once Roman is in position, there will be a roughly 90-day commissioning period, during which the telescope will fully power up its instruments and run a series of diagnostic tests to ensure everything is in order before its mission truly begins.

There is, therefore, a slim chance that we could see Rubin's first photos before the end of the year. However, NASA officials have tentatively predicted that the telescope will start snapping the stars in early 2027. It took JWST about seven months postlaunch to send its first full-color image to Earth.

NASA representatives have promised that "data from all of Roman's surveys will be made public as soon as it is processed, with no periods of exclusive access," so once the images are ready, everyone will be able to see them.

As wildfires raged through Ontario, Canada in mid-July, millions of people in the Midwest and on the East Coast found themselves under a shroud of yellow skies, darkened by smoke from the infernos. The air quality index in Grand Rapids, Michigan hit 616 on July 16, breaking the previous record for the city of 350; any number over 301 indicates hazardous, emergency conditions.

Smoke events like this are only likely to worsen in the coming decades: Wildfires are one of the most imminent impacts of climate change.

Not only do the flames themselves directly threaten lives, but the smoke can trigger heart attacks, asthma attacks and premature births, as well as worsen heart disease or lung ailments such as chronic obstructive pulmonary disease (COPD). And those effects can spread as insidiously as smoke travels.

A 2025 study found that the record-breaking 2023 Canadian wildfire season may have shortened the lives of 87,000 people exposed to the smoke plumes worldwide. Another 2025 study found that wildfire smoke contributed to 41,380 excess deaths per year in the U.S. between 2011 and 2020 and that the number will rise to 71,420 excess deaths by 2050 if global temperatures rise 5 to 8.3 degrees Fahrenheit (2.8 to 4.6 degrees Celsius) by the end of the century.

In North America, the health impacts of this extra fire are likely to be significant. Wildfire season is getting longer and more intense in the West and Southwest, while regions not historically prone to wildfires will need to deal with the impacts of smoke plumes that can travel thousands of miles.

"Wildfire smoke is the fastest-growing environmental threat [to health] in the U.S.," said Marshall Burke, a professor of global environmental policy at Stanford University who was the senior author of the study predicting the grim rise in excess deaths. "It's just changing so rapidly."

Longer fire season, bigger blazes

Even a rapid drop in greenhouse gas emissions wouldn't fully mitigate the growing risk of wildfires. Because these gases persist in the atmosphere for decades, a more fire-friendly future is already locked in.

"No one foresees changes in the near future, at least, that are going to result in decreases in wildfire," said Mary M. Johnson, a principal research scientist in environmental health at the Harvard T.H. Chan School of Public Health. Wildfires are "predicted to increase in size, intensity and frequency."

Global data suggests that without climate change mitigation, fires will increase in all vegetation types by the end of the 21st century. Even if warming is held to 2.2 F (1.5 C) over pre-industrial temperatures ‪—‬ an increasingly challenging goal to meet ‪—‬ fires outside of tropical latitudes will become more frequent.

In the U.S., the picture is bleak. Between 1984 and 2015, the number of large wildfires in the U.S. West doubled, according to the National Oceanic and Atmospheric Administration (NOAA). The seasonality of fire is also shifting. A February 2026 study published in the journal Geophysical Research Letters found that climate change is nudging fire season in the boreal forests of Alaska and Canada forward as winter snow vanishes earlier, leaving spring vegetation dry and ripe to burn. In the U.S. West, on the other hand, fire season is stretching later because of summer drought.

"It's about dryness," GRL study senior author Hongliang Zhang, an air quality researcher at China's Fudan University, told Live Science.

Climate change warms the atmosphere, and a warmer atmosphere can hold more water. But changes in precipitation patterns can still lead to increased dryness and drought, Zhang said. With climate change weighing the scales toward more intense bouts of rainfall, a particular location could see more precipitation but still experience a simultaneous increase in dry or drought periods, he added.

Zhang and his colleagues found that under a scenario in which temperatures rise by about 7.9 F (4.4 C) by 2100 — a high-emission scenario in which we do little to curb carbon output — fire season would move forward by about a week in Canadian and Alaskan forests, with some of the northernmost regions of Canada and Alaska seeing shifts of up to 23 days. California, with its Mediterranean-like climate, would experience a peak burning shift later in the season. In the Southwest, fire season under this scenario would start a week later but end more than a month later than it does now.

How wildfire smoke is poisoning the air

All of this spells bad news for human health in the U.S. More frequent and intense fires will fuel dramatic increases in air pollution. For instance, a 2020 study suggests that particulate smoke pollution levels will double or triple in the Pacific Northwest and Northern California under unmitigated warming by the end of the century. And even though the West is the U.S. region most prone to fire, wildfire smoke pollution won't stay there. Instead, it will travel across the country, worsening air quality on the East Coast and in the Midwest, Burke and his colleagues found. Depending on the level of warming, smoke emissions will increase 262% to 482% between 2046 and 2055 compared to 2011 to 2020, the researchers found.

Climate change also brings an uptick in severe weather, including winds, Johnson told Live Science. More wind means smoke can travel many thousands of miles. For example, the smoke from the 2023 Canadian wildfires reached Europe and Asia, and that trend is likely to worsen.

"There really isn't any place in the world now where you can say, 'I'm not going to be exposed to smoke,'" she said.

When wildlands burn, they produce PM2.5, a fine particulate matter that is small enough to slip into the bloodstream. Epidemiological studies have linked exposure to PM2.5 to a range of health issues, including dementia, kidney disease and lung cancer. The particles increase oxidative stress on cells in lab dishes, induce cell death, and cause DNA damage that can lead to cancerous mutations, among other impacts.

The damage is evident during big fires. For instance, exposure to wildfire smoke raises the risk of heart attack, stroke and other cardiovascular emergencies, according to a study of California emergency department visits during the 2015 wildfire season. Cumulative exposure over time, however, is how wildfire smoke causes the most deaths. Between 2006 and 2020, PM2.5 from wildfire smoke exposure was responsible for an average of 24,100 deaths per year in the United States, a study published in the journal Science Advances in February found. Smoke exposure worsened the death rate for every health condition studied, with neurological disease deaths rising most significantly.

Wildfire smoke may also fuel premature births. Just a week of wildfire smoke exposure raised the risk of preterm birth by 3.4%, a 2022 study found — and in a world where smoke exposure could span weeks, that could translate to a significant uptick in the rate of premature birth. Other studies tell a similar story: a 2024 study found risk of premature birth rises with every incremental increase in exposure to PM2.5 from wildfires during pregnancy. And a 2025 study found that preterm birth risk increased in the U.S. West with smoke exposure, regardless of whether that exposure was measured by high-smoke days, exposure to 4-day waves of smoke, or by the concentration of particulate matter in the air.

Wildfire smoke may also affect cognition: A 2022 study found that cumulative exposure to wildfire smoke over the school year was linked to slightly lower test scores for elementary and middle schoolers. And research using data from cognitive brain-training apps has also shown that performance on a cognitive task declines on high smoke days in adults. Over the long term, PM2.5 exposure from wildfires is linked to dementia risk.

Toxic cocktail

Researchers are still working to understand why wildfire smoke is so dangerous to the body. Smoke can contain a toxic stew of ingredients, especially when homes and buildings burn. Air testing after the 2025 Palisades fire in Los Angeles found high levels of silver and chromium-6 nanoparticles, the latter of which are carcinogenic.

Johnson and her team have found that smoke exposure leads to epigenetic changes associated with the immune system.‪‬ In other words, the person's DNA doesn't change, but the way it's translated into building proteins and cells in the immune system shifts. And epigenetic shifts can be passed along to the next generation. One shift is a decline in regulatory T cells, immune cells that help the body tolerate itself and harmless allergens. The immune changes probably play a role in why wildfire smoke exacerbates chronic diseases, Johnson said.

More smoke days can also affect health indirectly, by keeping people from going outdoors. In California, the heaviest smoke days actually have fewer emergency department visits overall, Burke said. On the smokiest days, when the air is noticeably hazy and may even smell like a campfire, emergency department visits for asthma-related reasons rise, but visits related to injuries or car accidents decline even more, probably because everyone is staying home. That may sound like a net benefit, but if forced quarantines happen repeatedly, they can worsen physical and mental health over time, making people more sedentary or less able to socialize.

"It's keeping people from doing things they would otherwise love to do," Burke said.

On the flip side, emergency department visits rise on days when the Air Quality Index indicates a moderate risk or a risk to sensitive groups.On these days, the air may not seem noticeably bad, and people may go out without realizing the amount of pollution they are inhaling until they start to feel ill.

"That's really consistent with this broader air pollution literature that, especially recently, has shown there is no safe exposure level to air pollution," Burke said.

With an increasingly wildfire-friendly climate in its future, Americans will be less healthy. There are ways to reduce the impact, however. Burke and his team have found that controlled burns put off less pollution than wildfires, while reducing the fuel load that turns wildland fires into smoke-churning infernos. An investment in managing fuels could ultimately be an investment in improving the country's health.

"It is within our power to correct that problem," Burke said.

This article is for informational purposes only and is not meant to offer medical advice.

Devastating flash floods near the Nepal-Tibet border have left more than 330 people dead and more than 1,500 missing — including 65 from the U.S. — following a glacier collapse early Wednesday morning (Aug. 26), according to Nepalese authorities and Chinese state media.

Data from a surviving water level gauge shows that the Trishuli River water level surged by 30 feet (9 meters) in just 30 minutes on Wednesday in the municipality of Galchhi, some 20 miles (33 kilometers) west of the Nepalese capital, Kathmandu, the International Centre for Integrated Mountain Development reported.

Videos posted to social media show people fleeing the oncoming wall of mud and water that has destroyed buildings and uprooted bridges. Meanwhile, authorities have warned the public to stay away from the banks of the Bhotekoshi, Narayani (also called the Gandaki or Gandak) and Trishuli rivers amid concerns of further flooding.

"Although this occurred at the height of the monsoon season, significant rainfall does not appear to have been the trigger," Jon Tunnicliffe, a river science researcher at the University of Auckland in New Zealand, said in a statement to the Science Media Centre. "Preliminary investigations instead point to a large collapse of glacier ice and rock high above the Lhende Kola [river]."

The impact of this glacial material was so powerful that the U.S. Geological Survey (USGS) initially confused it for an earthquake. The seismic shock reached magnitude 5.2 ‪—‬ equivalent to a moderate earthquake. The USGS's subsequent analysis of the seismic waves produced also indicate that the signal was produced by a glacial collapse and debris flow.

Based on satellite images, researchers suspect the ice and rock shed by the glacier entered the Lhende Kola river valley at an elevation of around 17,060 feet (5,200 m), according to Tunnicliffe. He added that scientists are investigating the possibility that the debris may have temporarily blocked the river before releasing a larger surge downstream.

"That sequence is what geomorphologists call a hazard cascade — instability high on a glacierised slope becomes an ice-rock avalanche; that can block a river, entrain water and sediment, and transform into a debris-laden flood travelling tens of kilometers downstream," Tunnicliffe explained.

These processes are familiar, he said, but the danger comes from the connections between them, turning what may have started as a localized failure upslope turned into a catastrophe for the people far below in the valley.

However, Tunnicliffe cautioned against attributing this specific event entirely to climate change.

"There is an important climate change context here, but we need to be careful about attribution," he said. "We do not yet know why this particular glacier failed.

"What we do know is that conditions across the Hindu Kush Himalaya are changing rapidly," he added. "Glaciers are retreating, permafrost is degrading, new lakes are forming and steep slopes are being exposed and destabilised. Climate change can amplify hazards that already exist by altering the thresholds at which one process triggers another."

Tunnicliffe warned that in such events, the danger does not necessarily end after the initial surge passes. Instead, material deposited in the flood's wake can raise riverbeds, divert channels and create temporary new dams, all of which can set off further hazards in the following days, weeks or even years.

Basanta Raj Adhikari, director of the Centre for Disaster Studies at Nepal's Tribhuvan University, agreed that there is a risk of "second and third waves" over the next couple of days, he told BBC Newsday.

"We don't know yet," he cautioned. "There isn't high rainfall, but [a] landslide might happen." Adhikari said he is continuing to discuss the risk with colleagues in China who are monitoring the situation.

With an eye to the future, "the broader lesson is that we increasingly need to manage hazard chains, rather than individual hazards," Tunnicliffe said.

Satellite monitoring of glaciers, lakes and slopes must be combined with seismic monitoring, river gauges and warning systems capable of detecting cascades once they begin, he said, and we need to plan infrastructure, evacuation plans and land-use controls with the risk of future disasters in mind.

But for now, "Our thoughts are with the families of those killed and still missing, and with the Nepali and Chinese agencies and communities carrying out the search," Tunnicliffe said.

Earth is getting hotter, and people across the world are starting to feel the effects. The past decade includes all 10 of the warmest years on record, and 2024 was the hottest year ever measured. As temperatures continue to rise and heat waves become more frequent and intense, that heat could severely impact people's health.

Extreme heat can affect the body in serious ways, such as dehydration and heat exhaustion, and it can lead to more severe conditions, like heatstroke or an increased strain on the heart and lungs.

How worried are you about these health effects as our planet heats up? Are rising temperatures changing the way you think about your health and fitness, daily activities, or the safety of your family and community? Answer our poll, and let us know what you think in the comments below.

Archaeologists working at a Stone Age site in Turkey have discovered a unique depiction of a person sitting on the back of a leopard. The 11,000-year-old statue may reflect the culture's fascination with virility and masculinity, experts say.

The statue was unearthed this summer at Karahan Tepe (also written as Karahantepe), a Neolithic site in southern Turkey, according to an Aug. 25 translated statement from the Turkish Ministry of Culture and Tourism.

The unique statue, which measures about 28 inches (70 centimeters) tall, was made in "a style unlike anything seen before," Mehmet Nuri Ersoy, Turkey's minister of culture and tourism, said in the statement.

Excavators found the statue on a platform that ran along the wall of a round structure about 10 feet (3 meters) in diameter, according to the statement.

Karahan Tepe is one of the oldest known villages in the world. It was built around 9750 B.C. in Turkey's Urfa province (also known as Şanlıurfa), where other early settlements, including Göbekli Tepe, were established. Several of these early settlements produced enigmatic artwork depicting men and wild beasts.

In 2023, archaeologists at Karahan Tepe unearthed an enormous 11,000-year-old statue of a man clutching his penis, which possibly represents an important ancestor. Another life-size sculpture of a man holding his penis, known as Urfa Man, was found near Göbekli Tepe in 1993. And in 2022, archaeologists working at the site of Sayburç in the Urfa region found a carved scene depicting two leopards, a bull and a man grasping his penis.

The newly discovered sculpture "seems to be a mirrored version of the known type of 'animal mounting on top of a human,'" Jens Notroff, a Neolithic archaeologist at the German Archaeological Institute who was not involved in the project, told Live Science in an email. A statue of a human with a leopard on their back was previously discovered at Karahan Tepe and is now in the collection of the Şanlıurfa Museum.

Notroff thinks the Sayburç leopard scene and the new statue of a person on a leopard may be linked.

"Leopards were common feline predators in the region," he said. "They are vigorous, dangerous animals, so probably challenging game for skilled hunters. That might have added to their symbolic meaning."

Although the exact meaning of the human-and-leopard motif is unknown, Notroff suggested it could relate to courage or strength.

"An individual fearlessly shown among these animals, as in Sayburç, or even apparently mastering one, as in this new sculpture from Karahan Tepe, could be read as maybe a symbol of power, of control over this vigor and danger," Notroff said.

The statue may also yield important new information about the earliest human settlements in the region, according to the statement.

"I believe this discovery, which opens the door to new questions about the earliest periods of human history, will have a wide impact on the scientific community," Ersoy said.

What do you know about the Paleolithic, Mesolithic and Neolithic eras? Find out with our Stone Age quiz!

SCORESBY SOUND, Greenland ‪—‬ There's no feeling more exhilarating than waking up inside the imminent path of a total solar eclipse to see a clear blue sky. It was Wednesday, Aug. 12, and after over two years of planning, I was in the farthest reaches of eastern Greenland's beautiful Scoresby Sound (or Scoresbysund) fjord system aboard the Aurora Expeditions cruise ship the Sylvia Earle. We were creeping toward Ukattip Kungersiva, also known as Harefjord, in the icy depths of Ofjord.

Up on the observation deck, I scanned the sky for even a slight cloud. There was not a trace. I addressed the planet directly: "Are you kidding me?!" I smiled with utter joy, as it had been 1,210 days since my last clear view of the sun's corona — an eternity for an avid eclipse chaser like me. Clouds had thwarted my previous eclipse chase in Texas for the 2024 total solar eclipse, which was followed by almost two-and-a-half years without a total solar eclipse.

Today, 117 eclipse chasers on the expedition were depending on the decisions made by a few of us on the ship — the ship's captain, the expedition leader (and noted Arctic adventurer) Greg Mortimer and I. We had taken a risk to position the ship in a glorious location — the confluence of four fjord channels, with icebergs passing below ice-capped mountains — and, it seemed, in good weather ‪—‬ and we were also almost bang on the centerline of the path, where the sun would be blocked by the moon for 2 minutes, 16 seconds. That was just two seconds off the maximum possible totality anywhere on Earth. We were asking Mother Nature for everything on offer, but there were zero guarantees, aside from the moon's dark shadow enveloping us and cutting the light.

The day before, we'd surveyed the aptly named Sol Glacier, a wall of ice on the shores of Scoresby Sund. The sound of thousands of tons of ice calving into the sea will stay with me forever, but I had the prospect of something else even more dramatic on my mind. We had to decide where to put the cruise ship for the total solar eclipse the next day. I looked at the latest cloud forecast and sighed; it showed a blue hole of sky far away on Greenland's Blosseville Coast, back the way we'd come from Iceland. Could we make it in time?

Yes, if we left soon. But watching an eclipse far out at sea could bring its own problems. The swell would make the ship unsteady, and mist and clouds were likely. Our first choice, the centerline of the path of totality down narrow Ofjord, had looked cloudy on forecasts all week, though the chances of clear skies had improved slightly today. I headed to the bridge — the ship’s command center — just as the latest forecast was updated. It was good news.

"We're seeing a trend for Ofjord to clear," said Mortimer, who, in addition to being expedition leader, is a mountaineer who's used to shooting for the summit when conditions allowed. To disappear down the channels of Scoresby was a risk; due to narwhals, the speed limit was just 3 knots (about 3.5 mph, or 5.6 km/h) — and there was no escape route. We decided to take the chance.

Being on a cruise ship that could change position paid off in spades. We had hugged the northern side of the fjord to prevent any rising clouds from blocking totality; as it neared, two other cruise ships joined us. The temperature dropped like a stone; three eclipse chasers watching from the ship's open-air hot tubs suddenly appeared to be the most sensible of all.

At precisely 5:33 p.m. on Aug. 12, I watched the sun's bright face finally disappear behind the moon's silhouette as both hung over the reddish rocks of Røde Fjord to the south. The light in Ukattip Kungersiva dissolved as a diamond ring appeared around the moon. As it faded, a luminous reddish-pink prominence — a loop of gas and magnetic fields protruding from the sun's chromosphere — took its place. It was quite possibly the s crispest, clearest and most beautiful totality to witness. The 117 guests stood in reverence throughout as they experienced something unique and impossibly precious.

Each totality is different, but this Arctic eclipse taught me much for the next one on Aug. 2, 2027. For that event, nicknamed the "eclipse of the century," I'll be on the centerline again ‪—‬ but this time, for 6 minutes, 20 seconds. I will witness it from a river cruise ship in Egypt at noon, with the eclipsed sun at 82 degrees — almost directly overhead. So it will be a literal pain in the neck, but worth it.

Should we lie down on the deck? We'll prop up binoculars with our eye sockets and spend six minutes with an all-sky corona. A few lucky observers will get to float in the on-deck pool. It will be scorching hot, but during totality, it will cool considerably. Repositioning likely won't be necessary, as there will be a less-than-1% chance of clouds.

Totality isn't just something you see; it's a landscape you briefly inhabit. In 2027, that landscape — the dark Nile busy with ships and traffic — will last the longest of any total solar eclipse for another 87 years. This time, there will be no risk but plenty of reward.

Opinion on Live Science gives you insight on the most important issues in science that affect you and the world around you today, written by experts and leading scientists in their field.

See how much you know about the sun with our sun quiz!

A striking red aurora may be visible to some skywatchers alongside tonight's blood-red partial lunar eclipse, astronomers say.

The full moon is expected to slide into Earth's shadow tonight (Aug. 27-28), casting an eerie red glow over 96% of the lunar surface. At the same time, the National Oceanic and Atmospheric Administration (NOAA) has issued a moderate (G2) geomagnetic storm warning for 9:03 p.m. EDT (1303 GMT) Thursday night (Aug. 27) — 20 minutes before the eclipse starts. According to NOAA, the resulting auroras may be visible over several states, ranging from New York to Idaho.

However, skywatchers farther north have better odds of catching both spectacular sights together.

"Though it's unlikely the moon and aurora would occupy the same part of the sky, observers in Canada and Alaska have the best chance to see them together," Tom Kerss, an astronomer and co-author of the "Little Book of Eclipses: An essential companion to solar and lunar events" (Octopus Publishing Group, 2026), told Live Science. "The further west you are, the lower the moon will be in the East during the deepest part of the eclipse, where it may overlap with the brightest region of the auroral oval."

The aurora borealis, also known as the northern lights, is an atmospheric phenomenon caused by the solar wind ‪—‬ clouds of electrically charged particles spewed from the sun. Most of these particles are deflected by the geomagnetic shield that surrounds our planet, but some get swept into Earth's magnetic field and channeled toward the planet's poles.

Once there, the particles collide with atoms and molecules in the atmosphere, causing them to heat up and glow and producing the mesmerizing light show we know as the northern lights.

The intensity of these lights depends on the strength of the solar wind that hits our planet. Yesterday (Aug. 25), a powerful M-class solar flare — the second-strongest class of solar flare — flashed from a restless sunspot called 4513, according to Live Science's sister website Space.com. This was followed by a large ejection of solar plasma known as a coronal mass ejection.

This cloud of electrified, magnetic gas is expected to reach our planet between Aug. 27 and 28, with NOAA forecasting moderate (G1 and G2) geomagnetic storm conditions from 5 p.m. to 11 p.m. EDT on Aug. 27. Meanwhile, the lunar eclipse will begin at 9:23 p.m. EDT, peak just after midnight, and end around 3 a.m. EDT Friday (Aug. 28).

The moon won't fall totally under Earth's shadow, so we can't officially call it a "blood moon," but it will be the deepest lunar eclipse anywhere in the world until the next total lunar eclipse on Dec. 31, 2028. This could allow for particularly unusual viewing conditions.

"Typically, a full moon competes with aurorae by brightening the sky, but when submerged in the Earth's shadow, it will be relatively dark, increasing the odds of spotting the northern lights," Kerss said.

The contrasting green of the auroral bands and coppery-red surface of the moon should make for striking views on their own. But with G2-class geomagnetic storms on the horizon, some viewers may catch a glimpse of an even rarer sight.

"If the northern lights are occurring over your horizon, you may even witness the high-altitude red auroras in concert with a reddened moon," Kerss said.

The colors of the northern lights are influenced by the different gases in Earth's atmosphere — primarily nitrogen and oxygen — and where these gases sit in the atmosphere, according to NASA. At lower altitudes, for example, oxygen usually glows green. However, during more intense geomagnetic storms, an aurora may reach oxygen particles high in our planet's atmosphere. At these altitudes, above 120 miles (200 kilometers), oxygen glows red.

Meanwhile, the moon appears coppery red due to the way Earth's atmosphere bends and absorbs light. Sunlight comprises a spectrum of colors, and the blue and yellow parts of this spectrum are absorbed by the atmosphere. However, red light gets bent, or refracted, by Earth's atmosphere, which directs it toward the moon and lights up our rocky satellite like a blood-red flashlight beam, according to the European Space Agency.

The patient: A 41-year old man in Iran

The symptoms: The man visited an outpatient clinic after a week of experiencing extreme discomfort during urination and pain above his pubic bone. His urine stream was weak, and he was unable to empty his bladder.

What happened next: The patient told the doctors that about a month earlier, he had begun to develop incontinence. He self-treated for two weeks by inserting superglue into his urethra.

At first, the superglue seemed to help. But after four days, he began to produce less and less urine and urination became painful. By the time of his clinic visit — two weeks after he stopped applying the superglue — he was barely able to urinate at all and was in constant pain, his doctors wrote in a report of the case.

The diagnosis: During a physical examination, the doctors noted that the man's penis was erect and that they felt a solid foreign body in the penile urethra. They also observed "brittle fragments of superglue" on the opening at the tip of his penis, they wrote in the report.

The doctors attempted to perform a cystoscopy, a procedure in which a tube fitted with a lens enables doctors to look inside the urethra. But the obstruction prevented them from inserting the tube far enough to see anything, and they decided to perform emergency surgery to remove the mass of hardened glue.

The treatment: Surgeons made an 0.8-inch (2 centimeters) incision in the glans, the bulb at the end of the penis. For 15 minutes, they bathed the urethra with 0.8 gallons (3 liters) of saline solution to saturate the glue plug and thus separate it from the walls of the urethra ‪—‬ a feat they eventually accomplished through "certain maneuvers," they wrote.

Finally, the glue broke loose. The doctors extracted a rod-shaped solid glue block measuring nearly 4 inches (10 cm) long.

After the patient recovered from surgery, his urination and urine analysis were normal. He was discharged five days later with a catheter that remained in place for 10 days, and he received prescriptions for antibiotics to prevent infection. At a follow-up visit in the sixth week after surgery, his urination was normal and he had no further complications.

The doctors did not identify the cause of the patient's prior incontinence.

What makes the case unique: Application of superglue in body cavities typically occurs in the ear or nose, according to past case reports. Usually, the glue can be dissolved with solvents, such as acetone. However, three other case reports in the medical literature describe patients intentionally inserting superglue into their urethras, and all of those cases required removal with endoscopy or surgery, the doctors in Iran reported.

Urethra tissue is very delicate, and inserting anything into this sensitive tube risks damaging it, which can lead to serious infection. The insertion of foreign bodies into the urethra can also be painful, making the practice "relatively rare," the report's authors wrote.

If a person chooses to do this, they added, it may be to satisfy curiosity or as a result of intoxication or mental illness, but the most common motivation is sexual stimulation. Despite the risks, numerous case reports describe people pursuing pleasure by introducing a wide range of diverse objects into their urethras, including magnets, pencils, earphones, a dining fork, a thermometer, the ink chamber from a ballpoint pen, the metal tip of a screwdriver, a USB cable, a tree branch and three AAA batteries.

For more intriguing medical cases, check out our Diagnostic Dilemma archives.

This article is for informational purposes only and is not meant to offer medical advice.

Can you guess the diagnosis in these strange medical cases? Find out with our diagnostic dilemma quiz!

President Donald Trump's recent executive order on childhood vaccines has generated a predictable and understandable debate around public health needs, parental autonomy and the scientific justifications for the directive. The order proposes, among other things, altering the U.S. childhood vaccine schedule and splitting up the combined MMR vaccine into multiple shots. As an immunologist, my view is that the order contradicts established scientific consensus and instead backs narratives that are not supported by evidence.

However, the more important issue with the order may be something more fundamental: What happens when vaccine policy is divorced from the scientific processes designed to guide it?

For many decades, the U.S. relied on a transparent process in which scientists, physicians, public health experts and vaccine specialists reviewed evidence and developed recommendations for who should receive a given vaccine and when. Through this process, there would be disagreements, which is not only expected but welcomed. Constructive debate on policy can lead to the development of better policies. But replacing expert scientific review with political directives risks creating a precedent that extends well beyond vaccines.

It's very possible that the immediate impact of the executive order will be limited. Many pediatricians, state public health agencies and professional medical organizations are likely to continue following established immunization schedules that were developed through decades of scientific review and real-world experience. The order itself does not magically change how vaccines work, how doctors practice medicine, or how states set school vaccination requirements.

Indeed, while the order says a lot, it doesn't hold direct authority to change vaccine recommendations. These, at least for now, are still protected by federal laws. The order can set direction but not policy.

Nevertheless, it would be a mistake to conclude that the order does not matter, because the true risk it poses is that it creates confusion and uncertainty for parents and caregivers, who only want to protect their children as best they can.

Vaccination programs rely on something fragile: the public's confidence. This confidence can be destroyed easily. Parents deserve to have trustworthy information when making decisions about the health of their children. Physicians, too, must trust that vaccine schedules reflect the best available science. Weakening those foundations of trust will further contribute to declining vaccination rates, even if no formal mandates change.

We are seeing this right now. U.S. kindergarten vaccination rates have continued to drop, falling farther below the thresholds needed for herd immunity. This is especially concerning at a moment when the U.S. is experiencing one of its worst measles outbreaks in decades, while other preventable infectious diseases are making a resurgence.

The executive order proposes separating the combined measles, mumps and rubella (MMR) vaccine into three individual vaccines — and this illustrates the problem. The proposal is framed as part of an effort to reduce the number of childhood immunizations, but it would do the opposite in practice.

Here's why. Today, during their first years of life, children receive two doses of the combined MMR vaccine, administered in two separate injections. Under the approach outlined in the executive order, children would need six separate injections to achieve the same protection.

The order also suggests that each immunization be administered at separate medical visits, thus tripling the number of visits needed to reach the same protection. For families, that translates into more time away from work, more missed school, more transportation costs, more co-pays for those whose insurance plans require them, and more opportunities for appointments to be postponed or missed altogether.

These practical consequences shouldn't be ignored. Every additional visit creates another chance for a child to fall behind on vaccinations. Every added logistical hurdle disproportionately affects families with fewer resources, less schedule flexibility or less access to healthcare.

What's more, the separate vaccines required to implement this policy are not even currently available in the U.S. Manufacturers would need to develop new production processes, conduct testing, navigate regulatory review and establish distribution systems for these separate vaccines, all to replace a combined vaccine with an extraordinary record of safety and effectiveness spanning more than half a century.

In short, the proposal would require substantial new costs and complexity just to replace a system that has been working exceptionally well and protecting children for decades. The combination MMR vaccine was developed precisely because combining vaccines reduces the number of injections, thus improving vaccination rates by ensuring children receive protection as early and efficiently as possible.

What is the rationale behind the executive order? Administration officials have pointed to differences between U.S. vaccine recommendations and those from some other developed countries, such as Denmark, which recommends fewer routine vaccines than the U.S. does. On the surface, that argument may sound reasonable — if another country administers fewer doses, why shouldn't the U.S.?

The answer is that the timing and number of vaccines are developed to suit different countries' wildly different healthcare systems and public health realities. Countries differ in disease prevalence, healthcare access, vaccination delivery systems, screening programs and population demographics. Some countries have more centralized healthcare systems that allow for easier preventive care follow-up, while others face different infectious disease risks than the U.S.

It is therefore unsurprising that schedules vary among nations, and the motivation to match other countries' schedules is arbitrary, rather than science-led. What matters more is whether recommendations are supported by evidence and whether they effectively protect children in America, specifically.

It may be months or years before we see the consequences of this executive order and the wider attacks on vaccines. It will be reflected through declining confidence in public health institutions, growing uncertainty among families, and increasing difficulty in maintaining high vaccination rates, leading to higher rates of disease and death.

That is why this executive order matters.

Whether formal policy changes will be implemented now or in the future is less the issue. What's more at stake is whether the order will drive Americans to rely less on scientific evidence and expertise when they're making decisions that affect their children's health.

I believe immunology is one of the critical scientific infrastructures that underpins modern medicine. Vaccine policy should be built on the foundations of that infrastructure, with the science and evidence guiding public health recommendations. When this fails, the results will be measured in the lives lost to preventable illness, and that's a future we must avoid.

This article is for informational purposes only and is not meant to offer medical advice.

Opinion on Live Science gives you insight on the most important issues in science that affect you and the world around you today, written by experts and leading scientists in their field.

Skywatchers are in for an ecliptic encore tonight (Aug. 27 to 28) as a very deep partial lunar eclipse promises to turn the full moon coppery red.

As the full moon slides into Earth's shadow, it will cast an eerie red glow over 96% of the lunar surface. In North and South America, every stage of the eclipse will be visible in the night sky, beginning at 9:23 p.m. EDT on Thursday night (Aug. 27), ending around 3 a.m. Friday (Aug. 28), and peaking just after midnight. Meanwhile in Europe, the eclipse will occur just before dawn as the moon sinks below the horizon.

The moon won't fall totally under Earth's shadow, so we can't officially call it a "blood moon," but it will be the deepest lunar eclipse anywhere in the world until the next total lunar eclipse on Dec. 31, 2028.

Why does the moon turn red during a lunar eclipse?

A lunar eclipse happens when the moon passes directly behind Earth and falls into its shadow. But instead of going completely dark, the moon turns a deep shade of coppery red. This is because of the way Earth's atmosphere absorbs and bends light.

Sunlight is made up of a spectrum of colors. The blue and yellow parts of this spectrum are absorbed by Earth's atmosphere. But red light is bent, or refracted, by our planet's atmosphere and directed toward the moon, lighting it up like a blood-red flashlight beam, according to the European Space Agency.

The exact shade of red depends on what else is going on in Earth's atmosphere at the time. For example, volcanic ash and desert dust can significantly darken a lunar eclipse.

Unlike with a solar eclipse, you don't need eclipse glasses to safely see a lunar eclipse.

While the partial eclipse will be visible to the naked eye, even better views are possible if you use one of the best telescopes, best smart telescopes or best stargazing binoculars. If you're looking to photograph the moon, check out our picks for the best astrophotography cameras to capture the best shots of the lunar eclipse.

Two people in Lancaster County, Pennsylvania, have died of measles, marking the first measles-related deaths in the United States this year.

Neither individual was vaccinated against the disease, the Pennsylvania Department of Health (DOH) reported Tuesday (Aug. 25). Their deaths mark the first measles fatalities in the state in 35 years.

"To protect the privacy of the individuals and their families, DOH will not release any additional details that could personally identify these individuals and their families," DOH officials said in the statement.

Since the start of the year, there have been 393 confirmed cases of measles in Pennsylvania across 28 counties. Nationwide, 2,813 cases have been reported so far this year, according to the Johns Hopkins U.S. Measles Tracker. The 2026 nationwide total already exceeds the total number of measles cases reported in 2025, when 2,289 cases were reported, including over 240 hospitalizations and three deaths, according to Centers for Disease Control and Prevention data.

These totals represent both measles caught within the U.S. and imported cases from people who caught the infection elsewhere. Imported cases make up a relatively small proportion of the overall total, with most cases coming from local transmission, according to the tracker.

The two deaths in Pennsylvania come as the nation's vaccination rate for measles continues to fall among kindergarteners and as the proportion of kindergarteners with vaccine exemptions is rising. The U.S. is likely to lose its "measles elimination status" later this year, which would mean the same outbreak strain had been consistently circulating in the country for over 12 months. Essentially, this suggests that although the U.S. officially eliminated measles in 2000, the disease is likely back in regular circulation.

According to the tracker, nearly all of the measles cases reported this year — 96% — have been among unvaccinated people or people with unknown vaccination status. Two doses of either the MMRV vaccine (which protects against measles, mumps, rubella and chickenpox) or the MMR vaccine are about 97% protective against measles infections. (Both vaccines offer the same protection against measles, but the latter excludes protection against varicella, or chickenpox. Kids who receive the MMR shot get a separate chickenpox vaccine.)

Measles infections can cause rash; fever; cough; runny nose; and red, watery eyes. About 1 in 5 unvaccinated people who catch measles are hospitalized, and there's a risk of developing complications like pneumonia or brain inflammation. In the U.S., 1 to 3 in 1,000 people with measles die of the disease. Those who survive the infection can develop long-term health problems, such as neurological disease or "immune amnesia," where the immune system loses ability to fight off pathogens it's encountered in the past.

"Because measles was largely eliminated in the Commonwealth for more than three decades, people are not familiar with this disease and don't fully understand the potential severity of the illness," Dr. Debra Bogen, Pennsylvania's secretary of health, said in the statement. "We want to ensure every Pennsylvanian has the information they need to protect themselves, their loved ones and their communities."

The best way to protect against measles is to get fully vaccinated, DOH representatives said in the statement.

This article is for informational purposes only and is not meant to offer medical advice.

Archaeologists in the Czech Republic have discovered a prehistoric structure they believe was a ritual center linked to the movements of the sun and moon. The center is around 6,500 years old — about 1,000 years older than Stonehenge.

The structure was discovered at Chleby in the Central Bohemian Region. Archaeologists found a circular enclosure consisting of a ditch that was about 750 feet (230 meters) in diameter and 8 feet (2.5 m) deep. Twelve entrances that led to the center of the enclosure were located in different spots around the ditch, the team said in an Aug. 18 statement.

Archaeologists suspect that wooden posts likely created the walls of the enclosure. Based on animal bones found in the ditch, experts think that the entryways were decorated with bull skulls and horns.

"The cult of the bull was an important religious symbol among the first farming communities and is known from many parts of prehistoric Europe," Jan Turek, an archaeologist at Charles University in Prague who is involved in the research, said in the statement. Bulls in these Neolithic cultures were likely symbols of strength and fertility.

Sun and moon

The shape and orientation of the mysterious structure are unusual for a Stone Age site, the archaeologists noted.

"Circular enclosures are completely unknown in our region for this period, which already makes the site exceptional," Petr Krištuf, an archaeology professor at the University of West Bohemia in the Czech Republic who is leading the research team, said in the statement. "But when we began to analyze the positioning of the entrances in detail, it became clear that their arrangement was not random. Their geometry creates a system that made it possible to observe the most significant moments of the solar and lunar cycles."

Specifically, the 12 entrances were oriented so that people inside the enclosure could observe important astronomical events, such as the moon's most extreme position on the horizon during its 18.6-year cycle. People could also observe sunrise on the summer solstice, the longest day of the year, and sunset on the winter solstice, the shortest day of the year, through the structure's entrances.

"For prehistoric farming communities, the connection between sunrise and the summer solstice symbolized a beginning, while sunset and the winter solstice represented an ending," Krištuf said. "The same principle can be seen along Stonehenge's main axis. We can now see that [this site] was designed similarly."

In later times, the ritual purpose of the Chleby structure seems to have changed or been lost entirely. Previous excavations at the site found burials of 18 people from the Bronze Age Únětice culture (circa 2300 to 1600 B.C.), a culture which had unique burials and artifacts, including the Nebra Sky Disc. The site may have still maintained a ritual purpose at this time. But in the Iron Age (circa 800 B.C. to 1 B.C.), a settlement was built over the Chleby site.

"By the Iron Age, the monument appears to have definitively lost its original significance. The ditch was gradually filled in, and an ordinary settlement was established on the site of the former sanctuary," Krištuf said.

Research is ongoing, and archaeologists plan to analyze the site's soil to learn more about the people who once lived there.

"In addition to artifacts and the remains of the dead, people leave chemical traces in the soil. These can help us understand how this exceptional site was used during different periods of prehistory," Jan Fišer, an archaeologist at the University of Hradec Králové in the Czech Republic who is involved in the research, said in the statement.

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