For the first time, archaeologists have analyzed the genetic material of Homo naledi, a mysterious 300,000-year-old relative of modern humans discovered deep in a South African cave system. What they found is unique in human evolution studies: Every skeleton known from the species is female.

"I think it is fair to say that they surprised us," Lee Berger, a National Geographic explorer-in-residence, told Live Science in an email, but H. naledi "has always been an enigmatic discovery."

Since 2013, Berger has headed the Rising Star project, which discovered nearly two dozen skeletons of small-brained, two-legged creatures, which the research team named H. naledi, within a cave system in South Africa's Cradle of Humankind.

Research over the past decade has revealed that H. naledi was unusual for having a small brain and upper body, similar to earlier australopithecines like Lucy, but a face, hands and lower limbs that were more human-like. In 2023, the Rising Star team suggested H. naledi may have used fire in the cave, and in 2025, they advanced the controversial claim that H. naledi buried their dead — a complex behavior unexpected for a human relative with such a small brain.

But a new study of H. naledi teeth published Wednesday (June 24) in the journal Cell may bolster the team's interpretation of the Rising Star cave as a burial site.

An international team of experts studied 20 teeth from H. naledi skeletons using proteomic analysis, a minimally destructive technique that sequences genetic material from ancient proteins. Proteomics is a burgeoning field, especially because these proteins can last longer than DNA. The team focused on amelogenin genes (AMEL), which code for proteins in dental enamel and vary by sex. While the gene variant called AMELX is found in both males and females, another one, AMELY, is found only in biological males.

In analyzing the H. naledi teeth, the team found no AMELY genes but plenty of AMELX ones, suggesting that all of the skeletons were from females. These included the nearly complete skeleton of Neo and DH1, the main representative of the species, both originally assumed to be male.

The result is surprising because there are no known ancient human cemeteries or collections of nonhuman primate skeletons that contain only females.

"The most likely reason for these robust results are, in my opinion, cultural selection after death for burial by sex and perhaps gender," Berger said. "There are many past human societies with sex-specific burial practices," study co-author John Hawks, a paleoanthropologist at the University of Wisconsin-Madison, said in a statement, but the H. naledi skeletons "are older than any known Neanderthal or modern human burial site, and it's remarkable to see that they may all be female."

"An already weird hominin"

The discovery that everything we know about H. naledi comes from female skeletons has surprised paleoanthropologists.

"The bottom line is this is a weird result from an already weird hominin," Elizabeth Sawchuk, curator of human evolution at the Cleveland Museum of Natural History, who was not involved in the study, told Live Science in an email. "The key thing to remember is that failure to detect evidence of AMELY does not mean there are no males in the sample — it just means that none were detected."

One possible reason for the lack of this gene in H. naledi skeletons is an AMELY gene deletion that is known to occur very rarely in some modern-human populations and that has been found in one Neanderthal male. If the AMELY gene doesn't exist in this H. naledi group, then the protein profiles of males would look identical to the profiles of females.

However, "it's very unlikely that this would be the case among even half of the 20 individuals we studied or for an entire population," study co-author Enrico Cappellini, a paleoproteomics professor at the University of Copenhagen in Denmark, said in the statement. "Either scenario, namely the absence of H. naledi males in the Rising Star cave system or a systematic deletion of their AMELY gene, is fascinating and would have deep implications for a better understanding of the biology and evolution of this species."

Studies of H. naledi, a species known from a single site, "continue to yield more questions than answers," Sawchuk said. "As the authors point out, this is a surprising result that requires more investigation."

Other hominins in South Africa

A second surprising result in the proteomic analysis was that H. naledi shares a gene variant with Paranthropus robustus, a human relative with a massive face and teeth that lived in South Africa around 1 million to 2 million years ago.

Proteomic analysis of four P. robustus skeletons in 2025 proved that limited genetic material could be recovered from ancient human relatives in Africa. The new study has revealed that some members of this species and H. naledi shared a gene variant related to collagen production, which is different from the genes found in modern humans, Neanderthals and Denisovans.

While H. naledi and P. robustus inhabited the same general geographic area, it is unclear if they lived there at the same time and overlapped or if they may have had an ancestor-descendant relationship.

"It is early days for sampling fossil hominins with ancient proteins, and until we build a better, bigger sample, we just don't know" what the shared genetic variant means, Berger said.

Building a larger database of ancient proteins from other human relatives that evolved in Africa, such as Australopithecus africanus and Homo erectus, may clarify where H. naledi fits into the picture of human evolution.

"Key data are missing from H. erectus and A. africanus that would help put this evidence into context," Sawchuk said. "For now, this is another curious finding that bears further investigation."

What does sex change?

In 2015, Berger and colleagues named the new hominin H. naledi and described what they presumed to be male and female variants of the species based on the skeletons' sizes. In many groups of human relatives and in modern humans, males are physically larger than females, on average. This assumption led the researchers to classify the presumed male individual DH1, discovered in the Dinaledi chamber of the cave, as the main representative of the new species.

But a 2024 study was the first to question the assumption that the H. naledi skeletons came from two sexes. In that study, researchers found variation in the teeth of H. naledi that was "so low that the possibility that one sex is represented by few or no individuals in the sample cannot be excluded," they wrote.

"Our study helps resolve the long-standing mystery of why Homo naledi lacked significant variation," study first author Palesa Madupe, a researcher at the Max Planck Institute for Evolutionary Anthropology in Germany, said in the statement. "It's probably because they could have all belonged to one sex."

If the proteomic sex analysis is correct and H. naledi does not have AMELY deletion issues, it means everything we know about the species comes from females. But this doesn't mean interpretations of the species are wrong.

"The only thing that has changed is that we have never seen a male!" Berger said. "When and if we do, we will have to extend the description to include male sex characters and the likely extension of certain aspects of variation."

The researchers hope their study paves the way for more proteomic analyses of human relatives in the future.

The new analysis proves that protein analysis of fossils from the Pleistocene (2.58 million years ago to 11,700 years ago) can be done in a minimally destructive way, Madupe said. "This means potentially opening the door to a whole new way of sustainably investigating the differences between sexes in groups of extinct hominins and other animals without causing visible damage to these priceless fossils."

What do you know about early humans? Test your knowledge with our human origins quiz!

An isolated population of sperm whales in the Mediterranean Sea are splitting into two distinct groups with different dialects, a new study reveals. This shift has likely been happening for thousands of years, as two groups split from an initial single population.

The findings, published Tuesday (June 23) in the journal Proceedings of the Royal Society B: Biological Sciences, are providing a rare insight into the process of different dialects emerging among non-human species.

The sperm whales (Physeter macrocephalus) live in small social units of females and young, and they associate with other groups in the same area. They use social vocalizations called codas ‪—‬ shortpatterns of clicks ‪—‬ to communicate. The particular codas they use identify them as being part of the same cultural group.

Taylor Hersh, a researcher in the School of Biological Sciences at the University of Bristol in the U.K. and first author of the research, and her colleagues have analyzed codas recorded over almost 20 years in the Mediterranean, where there is a unique population of a few thousand sperm whales, to see if they all use the same dialect.

Sperm whales entered the Mediterranean via the Strait of Gibraltar about 20,000 years ago, and they have spread throughout the area. The whales rarely leave the sea ‪—‬ even males, which normally migrate. Other sperm whales don't seem to enter often, either, so the Mediterranean ones are effectively isolated from other populations and are considered an endangered subpopulation.

"The sperm whales in the Mediterranean are really cool," Hersh told Live Science. "I've always thought of them as the weirdos of the sperm whale world in that they don't leave through the Strait of Gibraltar even though they could. They are unique, and for a long time, they were also thought to be acoustically unique."

The thinking was that all the sperm whales in the Mediterranean belonged to the same clan, identified by their use of a single coda 90% of the time. This coda consists of three clicks and then a pause before the fourth and final click ‪—‬ a pattern called the three-plus-one type.

But the analysis by Hersh's team of 5,291 codas recorded between 2003 and 2021 revealed that sperm whales living in the eastern Mediterranean around the Hellenic Trench, off Greece, have a slightly different dialect from that used by animals in the western basin around Spain's Balearic Islands.

The eastern whales produce a distinct form of the three-plus-one coda. "It's a very similar pattern of clicks, but it's much, much faster," Hersh said.

In some recordings, whales in the eastern Mediterranean produced the slower coda, showing they were familiar with both dialects.

"The western sperm whales religiously stick to their dialect, but there were four instances of eastern whales using the western dialect," Hersh said. "The question of why is still an open one. Their dialect seems to be a lot more diverse than we expected. They do occasionally make those slow three-plus-one codas, but they make a lot of other coda types, too."

Hersh hopes further recordings alongside records that tie individual whales to sounds and events might help elucidate why the whales switch between dialects.

"It's exciting to see this study showing different populations behaving closely, but also differently," said Gašper Beguš, linguistics lead at Project CETI, a nonprofit organization that aims to translate the communication of sperm whales.

The study paints a picture of sperm whales progressively occupying the Mediterranean from west to east, with the dialect of one group gradually changing. "The groups in the east clearly remember the western dialect because they have these 'throwback' days," Hersh said.

It's still a mystery how and why these dialects evolved.

"Every speech is a dialect; the question is how did they arise and why?" said Beguš, who wasn't involved in the new study. He said the historical change in habitat does help to show which dialect came first. "In the Mediterranean, maybe they're forming different groups, so that's why they're trying to distinguish themselves," he told Live Science, giving the parallel of young people who distinguish themselves from previous generations by coming up with new slang.

"It's possible that these two groups with repertoires that are very similar but still distinctive could represent a sort of midway phase,” Ellen Jacobs, a marine biologist at Aarhus University in Denmark who wasn't involved in the research, told Live Science via email.

"Changes in the rhythm might be a very feasible and meaningful way for coda signals to start to diverge," she said, like the way the English words "How do you do?" got mashed together until they morphed into "howdy."

The timescale on which a sperm whale dialect develops is uncertain, but it's likely a slow process, according to Hersh. "It's probably happening on the scale of hundreds and thousands of years, because sperm whales can live into their 60s and 70s. And this study is looking over 19 years of data, and that's just a snapshot of one animal's life," Hersh said.

This means the eastern whale dialect was conceivably emerging in the Mediterranean Sea as famous human civilizations were speaking different languages on the surrounding lands, including when the ancient Greeks and Romans were rising and then falling.

"Maybe if we could leave them for another 10,000 years, we would come back to find the completely separated dialects of clans," Jacobs said.

The patient: A 61-year-old man in Japan

The symptoms: The man visited a hospital because two months earlier, some foods and beverages began to taste extremely unpleasant to him. Over time, more foods had become difficult for him to stomach. Sour and salty flavors were the first to trigger disgust. Oily foods were next, followed by fresh vegetables, cold water and juice, warm water and, finally, sweets.

The man ate less due to the taste aversions, and he unintentionally lost a few pounds. He told doctors at the hospital that he felt lethargic, they wrote in a report of the case.

What happened next: The patient, who was a physician himself, reported that eight years ago, he had been diagnosed with bipolar disorder. For the prior three years, he had been managing the condition with lithium, a mood stabilizer commonly used to treat bipolar disorder.

He was taking a prescribed dosage of 800 milligrams per day and historically hadn't had any unusual side effects. (This is slightly higher than the typical dose recommended for chronic management of bipolar disorder, but that said, doctors may tweak patients' doses based on their individual needs.)

The diagnosis: Doctors performed bloodwork and found that the level of lithium in the patient's blood was 1.28 milliequivalents per liter (mEq/L). Safe levels of lithium are between 0.6 and 1.2 mEq/L; any higher than that can cause a condition called lithium toxicity, which can be fatal if untreated.

When the doctors checked the man's medical records, they found that prior to the onset of his symptoms, the levels of lithium in his blood were between 0.4 and 0.9 mEq/L. In the report, the authors did not investigate the cause of the toxicity, nor did they hypothesize as to why lithium was accumulating in the patient's blood.

The treatment: The doctors told the man to stop taking lithium, and they instead prescribed another mood-stabilizing drug, called valproate. As the lithium levels in his blood dropped, the patient's energy returned and the foods and beverages that previously disgusted him recovered their normal flavors. Notably, this happened in the reverse order that their flavors had changed.

At a follow-up visit one year later, the man was still taking valproate and his symptoms of fatigue and taste changes had not returned.

What makes the case unique: Although they're uncommon, side effects of lithium use can include confusion, increased thirst, frequent urination, irregular or slow heartbeat, tiredness and weight gain. Rarer side effects include dizziness, headaches, vision problems and heat loss in the arms and legs. Lithium toxicity, also known as lithium intoxication, is known to increase the risk of these adverse symptoms.

Changes in a patient's sense of taste while taking lithium have been recorded in just a handful of reports dating to the 1970s and 1980s. One patient lost the ability to taste salt, while another "noticed a strange and unpleasant taste associated with butter and celery."

Nevertheless, "it has not been generally known that lithium can lose or change taste in some patients," the case report authors wrote. Based on their findings, they suggested that in the future, taste loss or changes in taste perception should be flagged as a potential indicator of mild lithium intoxication.

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

A deep-space telescope on a grand mission to make the largest-ever 3D map of the universe just peered into the star-filled heart of the Milky Way. In the new observations, shared Wednesday (June 24), the Euclid space telescope imaged the center of the Milky Way in extraordinary detail, showing off more than 60 million stars crowded in the galaxy's center.

The shiny new image from the European Space Agency (ESA) spacecraft will help astronomers confirm newfound exoplanets and use changes in starlight to measure those planets' masses as they orbit their parent stars, according to ESA scientists.

The image was taken in 26 cumulative hours in March 2025, across nine pointings of the telescope's visible-light camera toward the galaxy's center, also called the galactic bulge. Each viewpoint captured a slice of sky larger than the full moon. In a statement, ESA praised the performance of Euclid under challenging conditions.

"Designed to observe billions of faraway galaxies, the space telescope's visible-light camera is sensitive enough to tell apart individual stars in our super-crowded galactic bulge, without being blinded," agency officials wrote.

The mosaic image will help NASA's Nancy Grace Roman Telescope with its upcoming planet-hunting mission, after that observatory launches aboard a SpaceX Falcon Heavy rocket from NASA's Kennedy Space Center in Florida no earlier than Aug. 30.

One way the Roman telescope will search for new worlds is through microlensing, the same technique that can be used to examine exoplanets in the new Euclid image. Microlensing happens when one star passes in front of another from the perspective of an observer. The gravity of the closer-up star briefly bends and magnifies the light of the star behind it, allowing possibly unseen planets to pop up near that star.

"During the last 20 years, almost 300 exoplanets have been discovered using this technique, all with ground-based telescopes and all towards the centre of our galaxy," Jean-Philippe Beaulieu, who initiated the Euclid galactic bulge survey and co-led the Euclid Consortium's exoplanet working group, said in the ESA statement.

"This image from Euclid includes 51 known planetary systems ‪—‬ and it will assist in studying many more that will be found," added Beaulieu, who holds positions at the Paris Institute of Astrophysics and the University of Tasmania in Australia.

A cosmic time capsule

Euclid's observing window was too short to find a microlensing event, which requires more than 20 days of examining one star to watch for a planet's orbit and associated changes in the star's light. But Euclid's work did allow astronomers to measure already-known planets. And once newer planets are confirmed by other telescopes, the image will let astronomers look back to confirm those newfound worlds' masses.

"In 24 hours, Euclid has already captured the stars involved in all the future microlensing events that the Roman space telescope will detect, but before the stars and planets involved have aligned," Natalia Rektsini, a postdoctoral fellow at the Paris Institute of Astrophysics who led the release of Euclid's galactic bulge survey data, explained in the statement.

"Anyone who detects a microlensing event in the same region, for example with Roman, will be able from now on to use Euclid data as a time reference in the past and see how the stars looked before they overlapped," she added. "Since Euclid can clearly separate individual stars, one can then measure how fast they move over time, and use that information to confirm the existence of a planet and determine its mass. This would not be possible with data from one point in time."

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Earth's oldest known impact crater formed when a meteorite slammed into what is now Australia about 3 billion years ago ‪—‬ 470 million years later than scientists previously claimed, a new study suggests.

The impact crater, known as the North Pole Dome crater, is located in Western Australia's Pilbara region, which is home to some of the planet's oldest rocks. It remains a record-breaking structure, beating the world's next-oldest known meteorite impact crater — the Yarrabubba impact structure, also in Western Australia — by roughly 800 million years.

"While the site had previously been identified as an ancient impact structure, its exact age remained uncertain," study first author Chris Kirkland, a professor in the School of Earth and Planetary Sciences at Curtin University in Australia, said in a statement. "The impact left a 'mineral clock' behind. By dating minerals that were remade or newly grown in the damaged rocks, we can now pin down when this extraordinary event happened."

In a study published last year, Kirkland and his colleagues said they had "unequivocal evidence" that the North Pole Dome crater was 3.47 billion years old, based on an analysis of cone-shaped chunks of rock known as "shatter cones" that form when the shock waves from a meteorite impact propagate downward.

However, a study published four months later in the journal Science Advances called the other team's results "inaccurate," arguing that the impact occurred no earlier than 2.7 billion years ago.

For the new study, Kirkland and his colleagues used advanced mineral dating techniques to estimate the ages of zircon, apatite, calcite and muscovite in shatter cones from the North Pole Dome crater. The researchers analyzed two samples of shatter-cone-bearing rocks, as well as a shocked quartz vein — a sheet-like deposit that typically forms when superhot, mineral-rich water circulates in the cracks between shocked rocks.

"The key evidence comes from zircon, a tiny but extraordinarily resilient mineral that can keep geological time for billions of years," Kirkland said. "Some zircons at North Pole Dome have unusual branching, skeletal shapes. We interpret these as impact-modified crystals, formed when older zircon was disrupted, partly recrystallised, and in places regrown during the intense heating caused by the impact."

The age recorded in zircon was the same as that locked inside apatite minerals, giving the researchers confidence that the impact occurred a little more than 3 billion years ago. The younger shatter cones in the Science Advances study may have formed subsequently due to tectonic and thermal activity, the team wrote in the new paper, which was published Tuesday (June 23) in the journal Geology.

"Ancient impact craters are incredibly difficult to date because over billions of years, rocks are altered by heat, pressure and fluids, which can obscure or reset the original impact signals," Kirkland said. "The new age places the North Pole Dome structure as Earth's oldest known impact crater and the only recognised example from the Archean eon [4 billion to 2.5 billion years ago], a time when the planet's earliest continents were forming."

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Using drugs to induce a hypothermia-like state may slow stroke-related brain damage, according to a new study involving lab animals and human patients.

The study used two existing drugs: the antipsychotic chlorpromazine and the sedative promethazine, called "C+P" when they're used together. This drug combo induced hypothermia and protected brain tissue in mouse and monkey models of stroke.

Additionally, an infusion of C+P was safe in an early trial including 32 human stroke patients, causing no notable side effects. However, no significant improvements in stroke outcomes were reported in a paper describing the results, which was published June 17 in the journal Science Translational Medicine.

More research is needed to determine what benefits C+P treatment may offer stroke patients. But the research sheds new light on the metabolic dynamics believed to be responsible for hypothermia's therapeutic effects, said Dr. Eric Landsness, an assistant professor of neurology at the Washington University School of Medicine in St. Louis who was not involved in the work.

"What's exciting about this study is that it's clear that it's not just the hypothermia, but it's the hypometabolism," said Landsness, who reviewed the paper before it was published.

Brain freeze?

The researchers tested C+P as a therapy for acute ischemic stroke, in which blood flow to the brain is blocked. Ischemic strokes are the most common form of stroke, accounting for over 85% of cases; "acute ischemic stroke" specifically refers to the medical emergency brought about by a sudden loss of blood flow to the brain and corresponding loss of neurologic function.

When blood flow is restored through a therapy called reperfusion treatment, "you can get significant injury from a lot of processes that were set in motion during the ischemia," said Dr. Patrick Lyden, a professor of physiology and neuroscience, neurology, and neurosurgery at the University of Southern California Keck School of Medicine who was not involved in the study.

To protect brain tissue from this double whammy of ischemia and reperfusion injury, some researchers have tried to harness hypothermia, which is "one of the most powerful ways of protecting the brain that we've ever studied in lab animals," Lyden told Live Science. "It's the standard by which all other brain protectants are measured."

In hypothermia, body temperature drops below 95 degrees Fahrenheit (35 degrees Celsius). Under normal circumstances, this can be very dangerous because the cold can slow down the heart and nervous system to the point that the body's cardiac and respiratory systems fail.

But one of the biggest theories for why hypothermia works in a therapeutic context is that it slows down our metabolism, similar to what's seen in animals during hibernation, Lyden said. "Because the metabolism is slowed, the death process in the brain is also slowed down."

Therapeutic hypothermia can protect the human brain following cardiac arrest, and it is also sometimes used to treat newborns with hypoxic ischemic encephalopathy, an injury that blocks blood and oxygen to the brain around the time of birth. However, studies of hypothermia in adult stroke patients have been less successful, Lyden said.

The C+P approach may be a more effective way to slow metabolism in stroke patients, the researchers hypothesized. In previous experiments, C+P reduced neuroinflammation in rodent models of stroke, possibly through changes in metabolic activity independent of hypothermia.

In the new study, the treatment was compared with two other methods of reducing core temperature in mice: a different drug, called adenosine 5'-monophosphate, and surface cooling using cold water and ice packs. While all three approaches induced hypothermia in the mice, only C+P treatment reduced their overall oxygen consumption and energy expenditure, two important indicators of slowed metabolism.

The paper highlights metabolism as more than a mere secondary effect of hypothermia, Landsness said; it's a process worth studying in its own right.

In mice, C+P treatment reduced the burning of sugar by the brain and brown fat, which burns fuel to generate heat. The treatment was also associated with less brain tissue damage and lactate accumulation, which can drive cell death, after stroke. These effects were also observed in rhesus monkeys treated with C+P.

According to the small safety trial with humans, the metabolic effects of C+P appear to extend to people.

The researchers measured lower levels of metabolism-associated proteins in the blood of patients who received the highest dose of the treatment tested. These were also the only patients to experience a significant decrease in body temperature at four hours after treatment, although their temperatures never dipped into true hypothermia. (Temperatures did fall that dramatically in the mice and monkeys.)

In people, C+P infusion did not reduce the degree of brain damage seen 72 hours after treatment, nor did it affect the participants' ability to perform daily activities without assistance after 90 days. Alongside the C+P treatment, the patients had also received standard reperfusion therapies.

The study authors, based at Capital Medical University in Beijing, did not respond to Live Science's request for comment. In their paper, they wrote that future trials could potentially establish the protective value of the C+P treatment in stroke.

In the current study, C+P did not trigger notable side effects in humans, but Lyden worried that the medications may still pose a risk of worrying effects. The two drugs could potentially interact in ways that cause symptoms like muscle spasms, seizures or changes in heart rhythm, for example. For that reason, it may be best to find different drugs that still slow metabolism but don't come with those risks, Lyden suggested.

To find an alternative to the C+P regimen, researchers will need a better sense of how the drugs exert their effects. The new paper "happened to fall upon a drug [combo] that happens to induce hypothermia and hypometabolism, but we don't necessarily know why," Landsness said. His lab is studying the neural circuits involved in hypothermia and hypometabolism, which could reveal new therapeutic targets.

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

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A massive wave of warm water is making its way across the Pacific Ocean as the newly declared El Niño gets into full swing, satellite images show.

The band, called a Kelvin wave, marks a swell of higher-than-average sea levels that stretches hundreds of miles along the equator. The anomaly is caused by warmer waters linked to El Niño — the warm phase of a natural climate pattern whose current iteration could become one of the strongest ever recorded.

The Sentinel-6 Michael Freilich satellite captured the deviations from average sea surface height on June 8. Red areas indicate higher sea surfaces than usual, while blue areas mark areas with lower surface heights.

Developed and launched in 2020 by NASA and the European Space Agency and operated by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), Sentinel-6 Michael Freilich measures changes in sea surface height down to fractions of an inch every 10 days.

The data complements measurements of sea surface temperature that have shown Pacific waters warming at unpreceded rates over the past several months, leading scientists to declare the start of a new El Niño on June 11. When ocean water warms, it expands and takes up more space. That translates to an increase in the height of the water relative to the satellite and the center of Earth, which is then picked up by the satellite's sensitive equipment. At some points along the equator, sea surfaces are now more than 6 inches (15 centimeters) higher than usual.

Kelvin waves like this one form when winds in the western Pacific near the equator weaken and temporarily reverse, blowing from west to east instead of east to west. That lets warm water gradually build up in the east, deepening the layer of warm surface waters and preventing colder waters from rising from below. The wave has now reached the western coast of South America.

NASA had already observed a few other Kelvin waves this year, suggesting an El Niño event was soon to follow. In January, Sentinel-6 Michael Freilich detected one near Micronesia that dissipated around mid-February. Another emerged in March and elevated sea levels near Peru by mid-May.

Changes in sea surface temperature or height can alter atmospheric circulation patterns and affect the weather. El Niño often increases rainfall in the southwestern U.S., Colombia, Peru and Ecuador, while rainfall in the western Pacific tends to decrease. The most recent El Niño, which lasted from June 2023 to April 2024, boosted global mean temperatures that made 2024 the hottest year on record and the first to breach the 1.5 degrees Celsius (2.7 degrees Fahrenheit) warming limit — a guardrail set by the Paris Agreement beyond which the effects of climate change become more and more catastrophic.

The June 8 conditions in the western Pacific were similar to those that occurred 1997 during a particularly strong El Niño, according to a statement from NASA. 2026 has seen fewer Kelvin waves so far than 1997, but this year’s El Niño is still ramping up.

"For now, it looks like it's going to be a big one — more so than I would have said last week — but we still need more observations to know what's going to happen," Severine Fournier, a sea level researcher at NASA’s Jet Propulsion Lab, said in the statement.

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Humans have been searching the stars for alien radio signals for decades — and so far, E.T. has not phoned home. But that doesn’t mean intelligent life isn’t out there, a new study hints. Rather, something else could be interfering: according to the research, space weather surrounding alien planets could be preventing us from detecting technological signals from extraterrestrial civilizations.

The findings, published March 5 in The Astrophysical Journal, offer a potential answer to the Fermi paradox: Given the size of the universe, there are many potentially habitable planets that could support life, and yet we have not detected technosignatures from any of them ‪— so, "Where is everyone?" physicist Enrico Fermi famously posited in 1950.

In the new study, researchers found that space weather caused by a planet's star could broaden hypothetical technosignals, dissipating their power over a larger range of frequencies and making them more difficult to detect.

"If a signal gets broadened by its own star's environment, it can slip below our detection thresholds, even if it's there, potentially helping explain some of the radio silence we've seen in technosignature searches," Vishal Gajjar, an astronomer at the SETI Institute and first author of the paper, said in a statement.

One way astronomers search for alien life is by looking for very narrowband signals, which are sharp spikes in the power of a radio emission. This spike usually only covers a few hertz.

"These don't occur naturally," Evan Keane, an astronomer at Trinity College Dublin who was not involved in the research, told Live Science. "So, if you see something very narrowband, you know that it is from something of interest." Astronomers would, for example, be able to easily detect some narrowband technosignatures on Mars, coming from the Mars rovers. But they have not observed any such signals from a clearly non-human origin.

Distorting signals

The new research argues that astronomers may have been looking for the wrong signal shape. In the new study, the researchers found that alien signals could be distorted by stellar space weather surrounding their home stars, which could explain why they have not been detected.

Space weather refers to changes in the space environment caused by charged particles, radiation and giant lumps of plasma called coronal mass ejections emitted by the sun. Other stars also generate space weather in their vicinity.

Gajjar and SETI colleague Grayce Brown investigated how space weather has historically impacted communications between Earth and spacecraft such as Mariner IV, which flew by Mars in the 1960s, and the Viking probes, which launched in 1977 for a voyage through the solar system and beyond. They created one of the largest collections of signal broadening examples and used that information to determine how other sunlike stars would affect the environment around their exoplanets. From this, the team calculated what would happen to a hypothetical alien narrowband signal that originated on one of them.

Then, they turned their attention to M dwarf stars, the most common type in the Milky Way. These stars account for three out of four stars in our galaxy, and some have been around since the early universe. That gives them a lot of time to have developed technologically advanced life, according to the paper.

There are no actual measurements of space weather around these stars, so Gajjar and Brown modeled what might happen to a narrowband technosignal that emerged from exoplanets and had to travel through interplanetary plasma. They found that hypothetical narrowband signals from these exoplanets were more likely to be smeared by space weather, making them even harder to detect.

In the paper, the authors propose a framework to estimate how much broadening would happen to a signal, given its frequency and the type of star its exoplanet was orbiting.

This new framework doesn’t totally answer Fermi’s infamous question, but it does give us a potential reason for the silence. The Fermi paradox "is not solely evidence for the absence of transmitters, but also a reflection of our detection limitations arising from a mismatch between the assumed signal morphology" and shape, the researchers wrote.

A step forward for SETI

Michael Garrett, an astrophysicist at the University of Manchester in the U.K. who was not involved in the study, welcomed the research.

"It is a solid contribution that SETI researchers and signal-processing teams should pay attention to," he told Live Science. "One of the strengths of the paper is that it's grounded in real measurements too, drawing on decades of spacecraft observations."

However, he emphasized that the paper focused on narrowband radio signals, which was only one way of potentially detecting an alien civilization. By contrast, Garrett's work explores the possible combined radio leakage from a technological civilization across a large range of frequencies.

Andrew Siemion, director of Breakthrough Listen Oxford Hub in the U.K. who was not involved in the research but collaborates with the SETI Institute, said this is the first paper to explore the space around exoplanets and its impact on detectability.

"The work offers a very concrete mechanism through which a candidate signal might ultimately be validated as having a likely origin with a distant planetary system," he told Live Science.

The authors recommended that future searches, especially with sensitive next-generation telescopes such as SKA-Low, take note of signal broadening when searching for civilizations beyond Earth.

Are you a UFO fanatic? Find out with our extraterrestrials quiz!

China controls some of the largest rivers in Asia, experiences heavy rain and has vast stores of water locked in glaciers in the west. But despite these abundant resources, China has a water problem. While central and southern regions are quenched by massive rivers like the Yangtze, the northeastern megacities like Beijing and Tianjin have endured serious water scarcity as agriculture, industry and population size rapidly increased.

To address the imbalance, China has undertaken one of the biggest engineering projects in the world: rerouting the flow of one of the world's mightiest rivers and its tributary, and ferrying the water thousands of miles from the center and south of the country to the thirsty north.

Called the South-to-North Water Transfer Project (SNWTP), the vast system of canals, pipes, dams, reservoirs and pumps moves staggering amounts of water via two routes through central and eastern China.

"It binds into a single network four major river basins, six provinces, three megacities, myriad bureaucracies, and more than 700 million people," Michael Webber, a professor emeritus in the School of Geography, Earth and Atmospheric Sciences at the University of Melbourne who specializes in regional economic development in China, wrote in a 2023 journal article.

But even this is not enough to satisfy the water needs in the North: China is currently expanding these routes and is planning a third, western route for the project, which would snake through the Tibetan Plateau before feeding the water-parched north and east. The route is attractive to Chinese officials because the river-and-glacier-threaded plateau, dubbed the Water Tower of Asia, has abundant water resources and is the source of numerous major rivers.

However, experts say the routes could worsen conditions in parts farther south that provide the water. What's more, the Tibetan portion of the project has stoked fears and suspicion in neighbors, as unofficial plans swirl suggesting major transboundary rivers could be diverted away from other countries and further into China.

The huge plan is "unbelievable," Mark Wang, a professor of human geography at the University of Melbourne, told Live Science. "The proposals [have] underestimated the negative impacts — environmental, earthquakes, evaporation and economic cost," as well as the international impacts, Wang added.

Water imbalance

Construction of the SNWTP began in 2002. The eastern route has operated since 2013 and transports water from the mighty Yangtze from Yangzhou, near Shanghai, to the megacity Tianjin, which has a population of 15 million people. The central route, which goes from Danjiangkou to Beijing and Tianjin, began flowing the following year, carrying water from the Han River, or Hanjiang. Together, they have moved 21 cubic miles (88 cubic kilometers) of water more than 1,800 miles (2,900 kilometers) since they began operating, according to the Chinese government — more than double the maximum amount of water held in Lake Mead.

The motivation for this project is obvious: China must support nearly 20% of the world's population with just 6% of its freshwater reserves. And this water is not distributed evenly across the country. Northern China has nearly half of the country's population and more than half of its agriculture but just one-fifth of the country's freshwater reserves.

In some places, the imbalance is even more dramatic. Tibet, in the west, has 4.8 million cubic feet (136,800 cubic meters) of water per person, while Tianjin, in the Northeast, has just 3,990 cubic feet (113 cubic m) per person. The United Nations considers less than 1,000 cubic m (35,000 cubic feet) of fresh water available per person water scarcity and less than 500 cubic meters (18,000 cubic feet) per person as "absolute water scarcity." The average in the U.S. is 314,300 cubic feet (8,900 cubic m).

Water transfer

China has a long history of rerouting water to serve its needs. Parts of the eastern route, for instance, use the Grand Canal, which was first built in the fifth century B.C.

And the broad concept of transferring water from the south to the north was first laid out by Mao Zedong, China's first communist leader, in 1952.

"Control of water has been a key theme in Chinese history and mythology," Tom Harper, a lecturer at the University of East London specializing in Chinese foreign policy and international relations, told Live Science.

Currently, the eastern route, which stretches 715 miles (1,150 km) from the Yangtze River to eventually reach Tianjin, transfers around 4 cubic miles (15 cubic km) of water per year.

This water needs to travel 213 feet (65 m) uphill, meaning pumping stations have to raise the water along the route.

The central route, meanwhile, relies on gravity to channel around 3 cubic miles (13 cubic km) of water 790 miles (1,270 km) from Danjiangkou Reservoir, on the Han River in Hubei province, to eventually reach Tianjin.

The Danjiangkou Reservoir already existed before the commencement of the project, but it was significantly expanded to raise the water level — and required 350,000 people to be relocated as a result.

The routes are now key to providing water to Beijing and Tianjin. For example, around 70% of Beijing's water comes from the route, experts told Live Science.

Fixing the fixes

The Chinese government and many Chinese scientists have boasted that the project has increased the water supply to people in northern China, raised the groundwater table in northern regions, and increased economic activity and agriculture in the region.

A major part of the project also focused on improving water quality: Freshwater supplies in China are heavily polluted, which reduces the amount of drinkable water.

"These were reservoirs, these were rivers, these were groundwater resources that had severe pollution impacts," Darrin Magee, a dam expert at Western Washington University, told Live Science. "So in the south where we had abundant water resources, the quality tended to be very bad in some areas."

To rectify this, the SNWTP installed water-cleaning stations along the route and the government implemented measures to reduce water pollution, including shutting down or relocating hundreds of manufacturing businesses that dumped their waste into waterways along the routes.

Along the eastern route, "pollution was terrible," Wang noted. "The central government put in a lot of effort… and they have control of the pollution again in a short period of time," he noted, adding that the water quality has significantly improved along the routes.

However, experts have said that the massive project has damaged ecosystems, displaced hundreds of thousands of people and fueled saltwater intrusion into underground reserves in water-providing areas, as the Yangtze River's freshwater flow is reduced.

"When the South-North Water Transfer was being proposed, many, many Chinese scientists were also against it because you just create lots and lots of new problems, whatever you fix," Emily Yeh, a professor of geography at the University of Colorado Boulder who specializes in Tibet, told Live Science. "Why not conserve water instead?"

Other experts agreed. "The water problem in China, it's not just physical water scarcity, it's the structural problem," Wang said. The biggest driver of water consumption is farming irrigation, which is water-intensive and leads to significant water loss. Conserving that water would go a long way to alleviating water scarcity, Wang added.

If China's "first priority is conservation, you won't need a large-scale, world's largest mega project," Wang said. Chinese authorities seem to be realizing this. They're also attempting large-scale water conservation policies, Wang said.

But the country is forging ahead with engineering projects.

The SNWTP's sources, particularly along the Han River, have less water per capita than the world's average, so siphoning off large amounts of the river's water could severely strain local areas. This has become such a problem that Chinese authorities are now undertaking even more engineering projects to alleviate the problem caused by the SNWTP. For instance, a new, smaller diversion is being added near the Danjiangkou reservoir, because people downstream are not getting sufficient water, Wang said.

The central route is further being extended to improve Danjiangkou's water levels. The central route relies on gravity, so a high water level is required for the route and the reservoir's dam to function. If water levels dip too low, as happened in 2011 during droughts, the dam stops working. So, engineers are connecting the Danjiangkou reservoir to the Three Gorges Dam, the world's largest dam, on the Yangtze, to increase the water supply.

The project is "a fix to fix the fix to fix the fix," environmental researcher Stevan Harrell wrote in the Made in China Journal — emphasizing the ever-growing number of engineering projects to deal with poor water governance.

Western route

Even though the two existing routes provide vast amounts of water to the North, and other water-conservation measures are being rolled out, Chinese authorities say the supply to the North is still not enough to meet demand, and that more water diversion is necessary.

The SNWTP's planned western route through the Tibetan Plateau won't start operations until at least 2050, but since its earliest planning stages, it has been mired in controversy.

The western route's official path would take 4 cubic miles (17 cubic km) of water per year from the Tongtian, Yalong and Dadu rivers — all tributaries that eventually feed into the Yangtze. The route would cross about 190 miles (300 km) of the Tibetan Plateau to the Yellow River, which then flows to the water-scarce north and east. The government has commissioned more feasibility studies for this route as part of the country's newly announced five-year plan.

The construction of such a massive project is fraught with difficulty. The Tibetan Plateau rises 10,000 to 15,000 feet (3,000 to 4,500 m) above sea level. These high altitudes present several problems, such as challenges in construction and maintenance, and difficulties in preventing water from freezing.

To transfer water across the plateau, the route would require pumping stations, along with a series of 300- to 1,000-foot-tall (100 to 300 m) dams, which would rank among the tallest dams in the world. The project would also require cutting 200 miles (300 km) of tunnels through the mountains, including the Bayan Har Mountains, which separate the upper Yangtze and Yellow River drainage basins.

The Tibetan Plateau is very seismically active, meaning earthquakes could lead to collapses or landslides, potentially damaging the vast infrastructure.

In 2018, Chinese scientists attempted to overcome the difficult terrain by transferring water through the air. But the "Sky River," or Tianhe project, ultimately proved unfeasible and has been effectively cancelled.

But China has not been deterred by these obstacles. The ongoing construction of the Dianzhong Water Diversion Project, in Yunnan province in southwest China, provides a test case for transferring water across mountainous, earthquake-prone landscapes. The damless design relies on a 380-mile-long (610 km) series of 58 tunnels, as well as pumps, to carry water through the mountainous and seismically active terrain. It is the "the world's longest water tunnel that could fit two high speed trains" and is "seen as a pilot demonstration project that will inspire and inform the design for the Western Routes," according to the Hong Kong-based think tank CWR. The first stage of the Dianzhong project is due for completion later this year, with a second phase recently announced.

Red flag

While the official western route has yet to break ground, alternative proposals have caused serious concern in neighboring countries. One unofficial plan developed in the 1990s, which politicians and academics subsequently considered completely unworkable, suggested funneling 48 cubic miles (200 cubic km) of water (four times the flow of the Yellow River) away from the Brahmaputra River, which flows into India and Bangladesh, and diverting the water toward the Yellow River basin, which serves the North and East of China.

A second controversial proposal, known as the Red Flag River project, suggests diverting 14 cubic miles (60 cubic km) of water 3,700 miles (6,000 km) from the Lancang, Nu and Yarlung Tsangpo rivers (called the Mekong, Salween and Brahmaputra rivers when they leave China) across the Tibetan Plateau to the northern Xinjiang region, which has high water stress and is facing desertification. Officials suggested the plan could turn Xinjiang into China's "California." The diverted water could also potentially be rerouted toward Beijing, experts told Live Science.

Some experts have called these "semi-official" proposals, as they have no official government backing but have been discussed openly by researchers with heavy government backing and support in China, which the government wouldn't allow if these people were truly speaking out of turn, Wang said.

Despite no official government backing, the plans have worried neighboring countries, particularly India, due to fears that any water diversions on international rivers could significantly reduce vital downstream supplies. Massive water engineering projects are already being built in Tibet, such as the upcoming Motuo megadam on the Yarlung Tsangpo — close to the proposed starting point for the Red Flag River project.

"There's a lot of concern that there might be water diversion, because China has been talking about this for many, many years," Tenzin Norgay, a researcher at the nonprofit organization International Campaign for Tibet, told Live Science. "If it happens, it's going to be a huge risk to downstream countries."

Researchers have calculated that the Red Flag project would likely siphon around 20% of the rivers' upstream flows, though the overall water loss for the whole of each river is less than that. Regardless of the actual amount of diversion, the lack of international consultations and transparency is exacerbating suspicions, experts told Live Science.

A changing climate

While China is forging ahead with attempts to redistribute China's water and reduce water scarcity via the SNWTP, climate change could scramble those plans. An increased risk of droughts over the coming decades could compromise the SNWTP's ability to move water.

The Tibetan Plateau, which is a source of water for almost 2 billion people, is particularly at risk. The world's "Third Pole" is rapidly warming, leading its numerous glaciers to melt. This could lead to sudden flooding, followed decades later by reduced river flow as the glaciers disappear. Desertification, meanwhile, is also impacting the Tibetan Plateau.

"Short to medium term, [we'll] see an increase in runoff as melting begins earlier each year," Magee said. "But over the long term, decreased snowpack means less secure water resources for most of China."

Taming nature

China's water management approaches include vast dam-building projects, cloud seeding, monumental tree-planting schemes and water-transfer projects, all of which rely on technological and engineering solutions to control the natural world, experts told Live Science.

When it comes to megaprojects, "If there's any country that will do it, it's China," Magee said. "The People's Republic of Engineers."

Other experts agreed. "It is part of this idea that you can engineer your way out of these problems, even if it's with trees rather than with machines," Yeh said. "A large-scale engineering approach to the natural world has been a characteristic of Chinese approaches to perceived or real environmental problems."

This is particularly true for the Tibetan Plateau. "The government is really imagining Tibet as a source of ecological service for the rest of the country," Yeh said.

Other experts agreed that Chinese authorities typically take an engineering approach to attempt to manage nature.

But Wang noted that China faces big pressures, which is why its government is looking for big solutions.

"If you understand China's energy issues, you understand why China is doing this. If you understand the water and food security issues, you understand so many things China has done," Wang said.

From government surveillance programs to microchips in vaccines, technology-centric conspiracy theories have exploded in the digital age, adding to some of the best conspiracy theories already in existence.

While most probably seem laughable to the technically literate, some of these theories have spread like wildfire and had significant real-world impacts. And although most are complete fabrications, some do contain a kernel of truth — and others have turned out to be eerily accurate. Here's a rundown of some of the most pernicious technology conspiracy theories.

The Large Hadron Collider is opening a portal to hell

Verdict: Not True

The Large Hadron Collider, operated by the European Organization for Nuclear Research (CERN) in Switzerland, has been an obsession with conspiracy theorists almost since its opening in 2008. The organization has even seen it necessary to have a dedicated page on its website responding to some of the more outlandish claims.

One of the most persistent fears is that the machine could create a black hole that would consume Earth or open portals to other dimensions. At their most hysterical, these theories have suggested that researchers are deliberately opening the gates of Hell to communicate with demonic entities.

Unsurprisingly, physicists swiftly debunked these ideas. The collider uses magnetic fields to accelerate protons to extremely high speeds before smashing them together to create smaller particles. The goal is to discover new elementary particles that could help test theories about how the Universe works.

Creating even a microscopic black hole or wormhole would require an accelerator the size of the whole universe, say researchers. It would also decay in a fraction of a second thanks to Hawking radiation, which causes black holes to lose mass and eventually evaporate. Even if such a black hole was stable, which current physics suggests is impossible, it would take three trillion years to consume just one kilogram of matter.

Tracking microchips in COVID-19 vaccines

Verdict: Not True

When the COVID-19 pandemic hit in early 2020, governments took unprecedented steps to control its spread, including lockdowns and vaccine mandates. That proved fertile breeding ground for novel conspiracy theories, including the bizarre claim that authorities were sneaking microchips into vaccines so they could track people.

The theory’s origins can be traced to March 2020, when Bill Gates participated in a Reddit discussion about digital health passports. A Swedish website dedicated to biohacking misinterpreted his comments and published an article saying the billionaire wanted to use microchip implants to fight the pandemic.

Via a paranoid game of Telephone, this slowly morphed into the idea that the government was using the vaccine to implant tracking chips in citizens. Needless to say, the theory is nonsense. There is no evidence that any of the billions of people vaccinated against COVID-19 have been implanted with tracking hardware.

But by January 2021, one in 10 American adults believed the theory. More worryingly, a poll found that one in four Americans said they were uncertain whether vaccines contained microchips. The conspiracy was built on years of anti-vaccine disinformation, and further fuelled the vaccine hesitancy that made it so hard to control the pandemic.

5G networks spread COVID-19

Verdict: Not True

Another COVID-19 related conspiracy theory that gained significant traction claimed that the disease was being spread by newly installed 5G cellular networks. The theory became so widespread that cell towers were set on fire in several countries, and social media platforms were forced to actively combat its spread.

The idea is firmly contradicted by the overwhelming evidence that COVID-19 is caused by a contagious virus. And crucially, the virus spread rapidly in areas with no 5G coverage whatsoever. Nonetheless, the U.S. Federal Emergency Management Agency felt compelled to issue a statement clarifying that 5G technology does not cause coronavirus, while U.K. government officials dismissed it as a "crackpot conspiracy.”

The fears likely built on top of existing concerns about the health impacts of radiation from cellphone towers. But there is no credible evidence that existing technology causes health problems, and 5G should raise even fewer concerns. The radio frequency waves used by these networks are forms of non-ionizing radiation, meaning they lack the energy to damage DNA or cells in ways that could cause disease. High-band 5G uses millimetre wave frequencies that cannot even penetrate human skin.

The dead internet theory

Verdict: Partially True

The dead internet theory proposes that the web is now dominated by bots interacting with each other with minimal human involvement. The idea has been around for several years, but has been further fuelled by the recent rise of artificial intelligence (AI) chatbots and agents.

The conspiracy first surfaced in 2021 on the Agora Road's Macintosh Cafe forum, in a thread titled "Dead Internet Theory: Most Of The Internet Is Fake." The idea is that automated systems are being used to craft content designed to draw engagement and generate ad revenue. But the theory suggests that those interacting with this content are also bots.

While the extent to which this is true is debatable, there is an element of truth to the theory. Studies show bot traffic was responsible for 51% of all internet activity in 2024 — the first time bots surpassed humans. And since ChatGPT's launch, AI-generated content has exploded, with another study finding that 13.1% of websites now host such material.

This is leading to fears that the internet is being rapidly flooded with low-quality "AI slop" that could degrade its usefulness over time. Given that OpenAI CEO Sam Altman recently gave credence to the theory, this might be one to start taking more seriously. The evolution of this idea, fueled by AI, might permanently change how we use the internet in the years to come.

Governments can control the weather

Verdict: Partially True

Following the highly destructive hurricanes Helene and Milton in 2024, rumours swirled that they were the result of government weather control programs. One of the most prominent boosters of the theory was U.S. Congresswoman Marjorie Taylor Greene, who tweeted “Yes they can control the weather” to her 1.2 million followers shortly before Hurricane Milton hit.

While these specific claims are patently false, like many good conspiracy theories, they contain a kernel of truth. The U.S. government had been interested in weather control as far back as 1891 and had a serious "weather weapons" program in the form of Operation Popeye between 1967 and 1972 during the Vietnam War. Such practices were banned by the Environmental Modification Treaty in 1977.

Basic forms of weather modification also exist today, in particular cloud seeding. This involves dispersing materials like silver iodide into clouds, which can marginally enhance rainfall. Countries like China and Saudi Arabia use the approach to assist in agriculture. China harnessed this technology to ensure clear skies for the 2008 Olympics.

Proposals to fight climate change via solar geoengineering have also further fuelled conspiracy theories. This would involve spreading tiny particles in the upper atmosphere to reflect sunlight. But these approaches are a long way from the kind of weaponized weather control conspiracists dream of.

Phones eavesdrop on you for ad targeting

Verdict: Partially True

Many people have had the eerie experience of seeing ads for products appearing on their phone shortly after discussing them offline. This has led to a persistent belief that smartphones secretly listen to our conversations for advertising purposes.

The rumour has been around for decades, but Instagram head Adam Mosseri recently felt compelled to address it directly, stating the company doesn't use microphones this way and calling it a "gross violation of privacy." Multiple studies have also found no evidence of covert audio recording, and there are several reasons why it would be impractical.

For a start, constant audio recording would rapidly drain phone batteries and trigger visible indicators on phone displays. More importantly, unauthorized recording would create enormous legal liability for those who engaged in it.

But there is something potentially more unsettling behind the phenomenon. Online platforms, advertisers and data brokers are constantly collecting, curating and reselling every tiny piece of information they can glean from our online and offline behaviour. This allows them to develop incredibly accurate profiles of people to provide spookily appropriate, and timely, product suggestions.

Planned obsolescence

Verdict: Partially True

From clothes to consumer electronics and even cars, people increasingly complain that products don’t last as long as they used to. The theory of Planned Obsolescence suggests that this is no accident, and companies deliberately design products with short lifespans to force repeat purchases.

The idea has circulated for a long time and has some truth to it. There is historical evidence that companies have pursued obsolescence as a strategy — in the 1920s, for instance, major light bulb manufacturers came together to form the "Phoebus cartel," which colluded to reduce bulb lifespans to just 1,000 hours. General Motors also pioneered annual model changes to entice customers to buy newer vehicles, creating a template that other industries copied. Technology vendors are particularly guilty — think smartphones with batteries that degrade in just a few years, or no longer support software updates.

But the practice isn't necessarily aimed at tricking us into buying more than we need. Rapid product turnover makes things cheaper to manufacture and with technology in particular, consumers prefer paying less upfront for devices they'll replace soon to access new features. Durability comes at a price too, so customers are often happy to have cheaper products that may not last as long — for instance, clothes that children will grow out of.

Government-sponsored mind control programs

Verdict: True

There is a whole menagerie of conspiracy theories speculating that the government uses technology and drugs for mind control. One prominent recent example is the claim that the U.S. military’s High-frequency Active Auroral Research Program (HAARP) is secretly using radio waves to manipulate people’s thoughts.

While that specific claim has been firmly debunked, the idea that the U.S. government is attempting to control people’s minds is not so outlandish. In 1953, CIA director Allen Dulles launched a top secret program called MKUltra aimed at developing exactly those kinds of capabilities. The agency covertly contracted out 162 projects to various universities, research foundations and institutions to study how psychoactive drugs, hypnosis, electroshock therapy, sensory deprivation and various forms of torture could be used to manipulate people’s mental states.

Experiments were carried out on both volunteers and unwitting subjects, including prisoners, sex workers, soldiers and children. By the mid-1960s, the project’s backers concluded that while it was easy to dismantle a human mind, subsequently seizing control of it was beyond them, and they wound down research in 1964.

Investigative reporting by the New York Times uncovered the project in 1974 and led to a series of congressional hearings. But the bulk of documents related to the project had been destroyed the year before, meaning the true extent of the program remains a mystery.

Widespread digital surveillance

Verdict: True

Paranoia around the government’s ability to listen in on our phone calls or online communications is a defining feature of many conspiracy theories. But in June 2013, former CIA contractor Edward Snowden leaked a treasure trove of classified documents to journalists that validated many of these fears.

The revelations uncovered a mass surveillance network operated by U.S. intelligence agencies and their foreign allies to collect phone records and monitor internet activity across the globe. Most prominently, it uncovered the PRISM program, operated by the U.S. National Security Agency (NSA), which used secret court orders to demand internet communication data from technology companies.

The U.K.'s Government Communications Headquarters (GCHQ) was also revealed to be tapping into 200 fiber-optic cables around the world, allowing it to monitor up to 600 million communications daily.

The reports lead to widespread outrage because the surveillance targeted not only suspected terrorists and criminals but also ordinary citizens, journalists, corporations and 35 foreign leaders – most notably the phone of the German chancellor at the time, Angela Merkel. But despite an initial public outcry, Congress renewed many of these surveillance programs in 2018 with little debate, suggesting that widespread government surveillance remains alive and well.

Test your knowledge of unfounded beliefs, from flat Earth to lizard people with our conspiracy theory quiz!

This eye-catching satellite snap shows off a "bull's-eye-like" set of concentric cloud rings that formed above an erupting volcano on La Palma in Spain's Canary Islands.

The eruption, the first on La Palma in 50 years, began Sept. 19, 2021, when a fissure opened up on the western flank of Cumbre Vieja — a volcanic ridge that runs through the southern half of the island — and spewed massive lava fountains into the air. The violent outburst created a 660-foot-tall (200 meters) vent, dubbed Tajogaite, which continued to slowly pump out lava until Dec. 13, 2021.

The molten rock flowed into the Atlantic Ocean in a giant "river of fire" that destroyed a town and unleashed deadly gases that are still causing issues for locals today, Live Science previously reported.

The concentric cloud rings in this image are made up of steam, smoke and ash ‪—‬ known as an eruption plume ‪—‬ that rose above Tajogaite for weeks.

Normally, such a plume would continue to climb into the cold air of the stratosphere — the second layer of the atmosphere, which extends from around 6 to 31 miles (10 to 50 kilometers) above Earth's surface. However, when this image was captured, a rare "temperature inversion" created a layer of elevated warm air that acted as a lid, preventing the plume from rising and forcing it to spread outward, according to NASA's Earth Observatory.

The trapped plume created concentric rings that formed from the natural ebb and flow in the intensity of volcanic activity. This pulse in the emissions given off by the volcano is visible in time-lapse footage captured by the Izaña Atmospheric Research Center on Tenerife, another Canary Island.

The official name for this type of concentric cloud formation is a "gravity wave," according to the National Weather Service. However, the formation has nothing to do with gravity, and it's completely separate from the ripples in space-time called gravitational waves.

"River of fire"

During the 85-day eruption, around 7.1 billion cubic feet (200 million cubic meters) of lava — reaching temperatures of up to 2,000 degrees Fahrenheit (1,100 degrees Celsius) — seeped from the ground.

This molten rock traveled around 4 miles (6.4 kilometers), destroying around 3,000 buildings in the town of Todoque, before falling into the Atlantic Ocean in a fiery waterfall. The estimated damage exceeded 700 million euros ($780 million), according to the Spanish newspaper El País.

Where lava fell into the sea, around 4.6 million square feet (430,000 square meters) of new land was created. The reaction between the molten rock and the water also released high levels of volcanic gases, such as sulfur dioxide and hydrogen cyanide.

At least one person, a 72-year-old man who returned to his home prematurely, is believed to have died from inhaling these toxic fumes, according to AFP. Thousands of wild and agricultural animals are also thought to have been killed by the gases.

The damage was "truly terrible," Marie Edmonds, a volcanologist at the University of Cambridge, told Live Science at an event on La Palma in April 2025. "Most shocking to me is the closeness of the vent to the communities," she added when describing what it was like to visit the area. "It must have been absolutely terrifying to see the eruption so close."

The causes of inflammatory bowel disease (IBD) are poorly understood, but now, scientists have pinpointed a runaway immune response that may underlie the condition in some patients.

IBD, which is characterized by chronic inflammation in all or part of the digestive tract, affects millions of people worldwide. Its principal forms are Crohn's disease, which can occur at any point of the gastrointestinal tract, and ulcerative colitis, which affects only the colon and rectum.

While IBD patients may experience similar inflammation, the underlying cause may be different. Understanding those differences could potentially unlock new, targeted angles for treatment, researchers concluded in the new study.

"Identifying these patients early could eventually allow clinicians to move more quickly toward therapies that address the specific mechanism of disease rather than relying on a trial-and-error sequence of medications," Dr. Brad Pasternak, medical director of the IBD Clinic at Phoenix Children's Hospital, who was not involved in the work, told Live Science in an email.

A potential subtype of IBD

The genetics of IBD are complex, with past studies linking the condition to 300 "hotspots" throughout the genome. The strongest known genetic risk factor for ulcerative colitis is a gene variant called HLA-DRB1*01:03, but how this variant contributes to IBD has been unclear.

The new study, published June 10 in The New England Journal of Medicine, helps connect the dots.

A major clue had emerged in previous research by the same team, which tested the blood of two children with IBD. The kids had autoantibodies — immune proteins that target the body itself rather than germs — that were neutralizing a key anti-inflammatory protein called interleukin-10 (IL-10).

IL-10 normally works by inhibiting the secretion of pro-inflammatory proteins, so patients whose bodies block IL-10 are effectively releasing a brake that should be holding off inflammation, Pasternak said.

The researchers suspected that these autoantibodies could be one factor causing IBD. In their latest study, they sought to find out whether more IBD patients had the same autoantibodies.

The study included data from over 4,900 people with IBD and over 1,000 without the condition. Using two separate lab tests, the researchers analyzed blood samples from both groups, finding the autoantibody in 173 of the IBD patients, or about 3.5%. The autoantibody was virtually absent from the blood of the comparison group.

Then, in lab experiments, the team exposed immune cells to blood from the IBD patients who carried the autoantibody. This lowered the amount of IL-10 while triggering a pro-inflammatory response.

Study co-author Dr. Holm Uhlig, a pediatric gastroenterologist at the University of Oxford, told Live Science that identifying what drives the formation of the autoantibodies will be "a question of intense interest." For now, though, their data suggests that patients carrying HLA-DRB1*01:03 are far more likely to have autoantibodies blocking IL-10 than those without the variant.

Historically, the variant has been associated with severe IBD that can require major surgery to treat. "Currently, autoimmune responses are not at all part of the therapeutic repertoire, and that's why we feel it's a relevant study," Uhlig said.

Uhlig also noted that the subgroup of 3.5% of patients they identified is a "significant number," given the large overall number of IBD patients worldwide.

In general, many IBD patients are currently treated with therapies that broadly suppress inflammatory pathways, Pasternak said, but not everyone responds to treatment. This study points to a potential way to someday tailor treatments to the mechanism driving specific patients' diseases, he said.

Aside from offering personalized treatments for IBD patients, Uhlig said their findings may improve diagnoses.

"Patients could undergo genetic testing already in the early stage of their disease diagnosis," he said, "and then it would determine their susceptibility to develop autoantibodies."

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

Researchers have identified a new species of "walking shark," a rare group of small carpet sharks that use their fins to "walk" along shallow reefs.

A team of divers spotted the newfound shark, which they named Hemiscyllium dudgeonae, in the dark waters around the reefs of southeastern Papua New Guinea. Gliding along the rocks was a small, brown-spotted shark that they didn't recognize.

"I was so excited. … I didn't look very closely at the pattern and quickly caught it and took it back to the boat," Christine Dudgeon, a senior research fellow at the University of the Sunshine Coast in Australia, told Live Science in an email.

Dudgeon handed the shark to Jess Blakeway, a doctoral student and first author of a new study describing the shark. Blakeway "noticed that the shark had a different pattern to the one that we were looking for and called out to me: 'Chris, it's different.'"

The new shark is named the Dudgeon's walking shark after Dudgeon, in recognition of her 20 years of researching the Hemiscyllium genus.

The new find, described June 15 in the Journal of the Ocean Science Foundation, brings the number of known walking shark species to 10, each with their own unique body pattern.

"This discovery is exciting because a lot of new fishes, and in particular, new shark and ray species, tend to be deep sea, so finding something in very shallow [less than 3 feet, or 1 meter] of water is unusual and highlights that there is potentially a lot of biodiversity that we really don't know about," Dudgeon said.

Encountering a new species

The team had been searching for another walking shark species, called Michael's walking shark (Hemiscyllium michaeli), when they encountered the unusual shark.

"Michael's walking shark has leopard prints and Dudgeon's walking shark has small white dashes and brown dots all over its body," Dudgeon said. "But with only one specimen we were not sure if this was an anomaly or a true difference."

The researchers continued surveying nearby reefs, and within two days, they had located 11 additional Dudgeon's walking sharks across three sites. These included males and females, both juveniles and adults, with all displaying the distinctive body pattern. That consistency convinced the team that they were likely looking at an undescribed species.

Dudgeon and Blakeway used genetic data to test this hypothesis at their laboratory in Australia. By comparing DNA from the newly discovered sharks with genetic samples from the other nine walking shark species, they confirmed that the population represented a new species.

Walking on land

Walking sharks are notable for their unusual biology. Unlike larger, open-ocean shark species, walking sharks spend their lives near coral reefs. Their ability to "walk" across the seafloor using their pectoral and pelvic fins is particularly useful during low tide, when parts of the reef become isolated from deeper waters. "Walking" helps the animals remain active when oxygen levels drop so that they can continue hunting prey across reef flats.

Scientists think this ability evolved as a response to the challenging environment of tropical reef flats, where oxygen levels can shift dramatically as the tides rise and fall.

Studies indicate that some walking sharks can survive in low oxygen environments for hours, though more research is needed to understand how the sharks are able to do this, Dudgeon said.

So far, Dudgeon's walking shark has been documented at only three locations in Papua New Guinea. If future research confirms that the species has a highly restricted range, H. dudgeonae could be vulnerable to habitat degradation, climate change or overfishing.

Many walking shark species appear to stay close to the reefs where they were born, which limits their ability to recolonize damaged habitats. Species with small geographic ranges are often more susceptible to population declines because local disturbances can affect a larger portion of the total local population.

The discovery also shows how new shark species are still being found in regions that have received relatively little scientific attention. Dudgeon and her team plan to continue doing surveys in Papua New Guinea to study the new species in its home environment.

"I think many people are not aware of the wonderful diversity of sharks and their relatives, the rays, skates and chimeras," Dudgeon said. "Very few species are dangerous to humans and they are a wonderfully broad and eclectic group of animals. They continue to surprise and fascinate us."

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

The patient: A 29-year-old woman in Lithuania

The symptoms: The woman had been trying to conceive with her male partner but had not become pregnant. Two rounds of in vitro fertilization (IVF) also failed to produce a pregnancy, but gynecological exams did not find any underlying causes for why she was unable to become pregnant. (When the patient's doctors described the case in a report, they did not mention if any fertility tests were also conducted on her partner.)

However, the woman had a history of asthma and sensitivity to inhaled allergens, such as mold, cat fur and dust. So she visited a medical facility to see if her allergies might be affecting her fertility.

What happened next: At the facility, blood tests revealed that the woman had unusually high amounts of eosinophils, a type of white blood cell that defends the body against allergens. Skin tests showed that, in addition to the woman's known allergy triggers, she was sensitive to mites, pollen from weeds and grasses, and allergens from insects and dogs.

The patient was especially sensitive to a protein called Canis familiaris allergen 5 (Can f 5), which is found in dog dander and urine. Sensitivity to Can f 5 can also indicate sensitivity to similar types of proteins found in human semen, the doctors wrote in the report.

In an interview with an allergist at the facility, the patient confirmed that she experienced nasal congestion and sneezing after unprotected intercourse with her male partner. These symptoms were previously overlooked by other specialists during consultations about her inability to conceive, she reported.

The diagnosis: Doctors then conducted further allergy tests using samples of semen collected from the woman's partner. The patient's allergic response confirmed the doctors' suspicions that she had a human seminal plasma allergy. (Seminal plasma is the fluid component of semen that carries the sperm cells.)

Sensitivity to semen "is a potential cause of female infertility," because such allergies can trigger inflammation in reproductive organs, according to the report. It's not immediately clear if the allergy somehow complicated the woman's IVF treatments, as well, given semen would not have been present in the implanted embryos.

The treatment: Barrier contraception — namely, condom use — is the most common intervention for a semen allergy. However, the patient was still eager to conceive with her partner, so she rejected that strategy.

The only known treatment for reducing sensitivity to semen involves introducing the fluid into the patient's body in gradually increasing concentrations, to build up their tolerance to the allergens. But this course of treatment was unavailable in Lithuania, the doctors wrote. Instead, they recommended that the woman take antihistamine medication before intercourse to reduce the severity of her allergic reactions.

She followed their instructions but found this approach "ineffective," the doctors wrote. During a follow-up visit three years later, the woman said that she had still been unable to conceive. What's more, new allergic symptoms now appeared after contact with her partner's semen, including a burning sensation in her vulva, puffy eyelids and watery eyes. No further treatments were recommended, according to the report.

What makes the case unique: Worldwide, medical experts have documented about 80 cases of human seminal plasma allergy, and there is still much to be learned about its impact on pregnancy, especially in the presence of other health-related issues that could hinder conception.

The causes of infertility are often difficult to pinpoint. Therefore, "this case serves as a reminder that seemingly unrelated allergic conditions, when combined, can contribute to reproductive health challenges, warranting comprehensive evaluations," the woman's doctors wrote.

This article was first published July 23, 2025.

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

Oil lamps have been simple and popular light sources for more than three millennia. But during the Roman and Byzantine empires, many oil lamps were highly decorated works of art. This hanging lamp in the collection of the Metropolitan Museum of Art was made nearly 1,600 years ago in the shape of a human right foot wearing a sandal, likely as an early Christian symbol.

The bronze oil lamp is significantly smaller than a life-size foot, measuring just 3.25 inches (8.3 centimeters) long. Still attached to the lamp is a chain with a hook for hanging, which is over 17 inches (43.5 cm) long.

The right big toe rests against the spout of the lamp, which would have held the wick. A sandal covers the foot, its leather or cord thongs tied at the ankle. The sole of the sandal is decorated with a swastika, which in Byzantine times was known as a gammadion cross and represented good fortune.

At the back of the lamp, there is an opening at the ankle where the lamp could be filled with oil. The flat cover for the opening is topped with a cross, identifying the lamp as a Christian artifact, Vera Ostoia, a curator of medieval art at The Met, wrote in a 1969 study of objects from the The Met Cloisters.

The foot shape may have been a protective image that symbolized good health and healing, according to The Met, and it may have doubled as a symbol of Christian pilgrimage. But the symbolism may have run even deeper.

In early Christian times, oil lamps and the light they produced were metaphors for enlightenment and immortality rather than just functional, Ostoia wrote. This foot lamp may have been connected to Psalm 119:105, which reads: "Thy word is a lamp unto my feet, and a light unto my path," meaning that people should follow the word of God as their path in life.

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

When galaxies collide, it's less like a train wreck and more like a marriage: Two separate entities merge into a single massive celestial structure. But relationships are hard, whether you're a human or a galaxy — and this process may also "kill" the merging galaxies by unleashing star-quenching winds.

This mechanism may help to explain an enigma in the early universe. A glut of James Webb Space Telescope (JWST) observations have shown that galaxies grew surprisingly massive within 1 billion years of the Big Bang. Just as unexpectedly, many of these galaxies appear to have already stopped producing stars and grown quiescent (or dead) only about a billion years later.

Galactic winds have previously been considered as galaxy-killing culprits, but astronomers lacked the direct evidence to confirm that this process can meaningfully suppress star formation at such an early stage of cosmic history. Now, in a paper published June 10 in the journal Monthly Notices of the Royal Astronomical Society, an international team of astronomers has described how star-driven winds can quench galaxies, creating the kaleidoscope of quiescent structures observed by JWST.

Gas leak near the dawn of time

The researchers used JWST and the Atacama Large Millimeter/submillimeter Array radio telescope in Chile's Atacama Desert to observe a system of galaxies called CRISTAL-02 as it appeared only 1 billion years after the Big Bang.

With a stellar mass around 10 billion times greater than the sun's, CRISTAL-02 is a galactic merger that represents the latter stages of a multigalaxy collision. It also exhibits an immense plume of gas, almost as long as the galaxy system itself, that is escaping into space at hundreds of miles per second.

This immense outflow, comprising 1.5 billion solar masses, appears to be driven by the intense winds generated through a rapid burst of star formation, as well as star death, the study authors said. Both processes occur as galaxies collide, shocking large gas clouds into birthing new stars, including extremely massive ones that die within a few million years in violent supernova explosions.

The intense radioactive winds released from these young stars and their dying elder siblings can then suppress stellar formation, by energizing and dispersing pockets of cool molecular gas before it can gravitationally collapse to birth baby stars.

"The galaxy has a powerful wind that is ejecting material twice as fast as the galaxy forms stars," first author Rebecca Davies, an astrophysicist at the Swinburne University of Technology in Australia, said in a statement.

The CRISTAL-02 galaxy system may be forming around 260 new solar-mass stars per year — a rate three times higher than galaxies with similar masses and ages. Yet it's also losing more than 500 solar masses per year, — 20 times faster than typical massive galaxies, the researchers found.

"We don’t know much about how the first galaxies stopped forming stars. This work directly shows that process in action," co-author Andreas Faisst, an observational astronomer at Caltech, told Live Science via email.

"If the outflow keeps going, the galaxy will run out of gas to form stars in less than 100 million years from now — a blink of an eye in astrophysical terms."

A widespread cosmic phenomenon

This research offers a blueprint for galactic senescence, or gradual deterioration. "Almost half of early massive galaxies are interacting with other nearby galaxies, suggesting this isn't a quirk but a widespread cosmic phenomenon," Davies added.

But previous simulations have suggested that outflows from active black holes, rather than stars, may be primarily responsible for creating quiescent galaxies. Star-burst-driven outflows cease once star formation stops, whereas black-hole-driven outflows can persist for hundreds of millions of years afterward.

Therefore, the researchers cannot rule out that the CRISTAL-02 outflow was generated by a powerful black hole that was inactive at the time of the observation.

Additionally, the researchers compared the outflow from CRISTAL-02 with a sample of 99 other similar outflows spanning 12 billion years to determine whether this feedback process evolves over time.

They discovered that outflow efficiency has remained roughly constant across cosmic history, even as the internal properties of galaxies have changed while the universe has aged and expanded. Additionally, constraining the early-universe feedback mechanisms that dictate galactic evolution can help astronomers improve cosmological simulations that aim to explain why the cosmos looks and behaves the way it does today.

"If many early galaxies collide and experience rapid growth, then it may not be surprising that we see so many dead galaxies in the early universe," Davies explained. "CRISTAL-02 offers a natural solution to the mystery of why these massive galaxies live fast and die young."

These processes are still at work today, governing local star-dense sectors in our galaxy. They may also dictate its far off future, as the Milky Way could collide with our biggest neighbor, Andromeda, in around 4.5 billion years. When this merger occurs, it "will likely trigger a starburst associated with strong stellar winds — maybe similar to what we see in CRISTAL-02," Faisst said via email.

"The Milky Way and Andromeda system will subsequently likely become a large quiescent elliptical galaxy."

As summer in the U.S. heats up, people become more diligent about protecting their skin from the sun. Another option for doing so will soon be available.

On June 9, 2026, the U.S. Food and Drug Administration approved the first new sunscreen ingredient to be permitted for over-the-counter consumer use in the U.S. since 1999 — a chemical called bemotrizinol.

Bemotrizinol isn't new — consumers in Europe and Asia have used it for decades. Some are hailing its long-overdue approval and arrival onto the U.S. sunscreen scene.

I am a biomedical engineer studying skin science — including the damaging effects of the sun's rays. To understand what bemotrizinol does and how it fits in with products already available to consumers in the U.S., let's take a tour of the physics of sunlight and sunscreens.

A short primer on sunlight

Our planet is irradiated by a yellow dwarf star 93,000,000 miles away that we fondly call the sun. It radiates light from its surface at a temperature of about 10,000 degrees Fahrenheit.

The Earth's atmosphere blocks most of the sun's radiation. Of the rays that get through, about half consist of infrared light — which gives you that warm feeling you feel on a sunny day — and 40% visible light, which you are probably familiar with as daylight.

About 10% of those rays are ultraviolet, or UV, light. UV light has the shortest wavelengths of the three types. That makes it the most dangerous — it's invisible and can damage living tissue.

Ultraviolet damage

Physicists further categorize solar UV light into several types, based on the wavelength, which is measured in nanometers. About 95% of it is UVA (315-400 nm) and 5% is UVB (280-315 nm). Sunscreens need to be able to block those rays from penetrating the skin.

The sun also emits two other types of UV light — UVC (200-280 nm) and vacuum UV (100-200 nm) — but these are stopped by the atmosphere, so sunscreens do not typically need to be able to block them.

Scientists used to think only UVB was harmful because UVB rays cause sunburns. But today, researchers know both types of UV can damage the skin.

UVB, with its shorter wavelength, has more energy, but UVA can penetrate the skin more deeply. And all UV can degrade the integrity of your skin, damage the structure of your DNA and cause skin cancer.

The only natural safeguard your body has against UV light is a microscopically thin layer of a pigment called melanin in your epidermis. The skin produces more melanin when exposed to the sun — that's what tanning is.

This extra melanin does protect the skin, but not fully. That's why protecting your skin with sunscreen is so important.

Sunscreens old and new

Sunscreens come in two different forms — mineral and chemical.

The first chemical sunscreen, developed in 1891, was an ointment made from quinine — a plant-derived compound that makes tonic water bitter.

Chemical sunscreens cover the skin in a transparent coating, acting like a solar sponge. They absorb UV photons and undergo a harmless chemical reaction, then dissipate the energy as heat. Bemotrizinol falls into this category.

Mineral sunscreens such as zinc or titanium oxide ward off the sun's rays by forming a protective film that also absorbs most UV light, but reflects some of it. Unlike chemical sunscreens, the film absorbs the light naturally, without a chemical reaction — which is why they are often visible as a white film on the skin.

Chemical sunscreens that have been available in the U.S until now combine ingredients like avobenzone, the most widely used UVA filter, with UVB filters such as octinoxate, octocrylene octisalate and homosalate. Working together, these substances protect the skin against the broad spectrum of ultraviolet rays.

These sunscreens are only effective for a short time because they are degraded by the chemical reactions they undergo, which means they must be frequently re-applied.

Another important element of sunscreen — whether mineral or chemical — is its Sun Protection Factor, or SPF. This number tells you how well a sunscreen prevents your skin from burning — in other words, what amount of UVB rays it absorbs.

An SPF of 2 would mean a sunscreen cuts your exposure to UVB rays in half, filtering out 50% of those rays. An SPF of 30 means the sunscreen lets just 1/30 of the rays penetrate your skin - which is 3.3%. So it blocks about 97% of the UVB rays.

Dermatologists generally recommend using a sunscreen with an SPF of at least 30.

Benefits of bemotrizonol

Bemotrizinol, while new to the U.S., isn't a new compound. European regulators approved it in 2000. Chances are, if you brought back sunscreen from a vacation in Mexico, Europe, Canada or South Korea, you may even have some laying around your house.

One benefit of bemotrizinol is its ability to filter both UVA and UVB rays, so it doesn’t have to be mixed with other products to do the job.

It has some other beneficial features as well. First, its molecules prefer to sit on the surface of the skin rather than being more readily absorbed into the bloodstream, which can occur for some formulations.

Such absorption has raised concerns that sunscreens might be harmful — though this has not been demonstrated in people, it may discourage some people from using it.

Bemotrizinol also does not degrade as readily in the sun than other chemical sunscreen products. That photostability means it can last for four to eight hours, rather than having to be applied every two hours or so.

Regardless of the type, as a skin scientist I can say with certainty that any sunscreen is better than none. Your skin does an excellent job protecting you from the world outside — so make sure you protect it in return.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

Explosive beams of energy crisscross through rainbow-colored space in a scene that evokes a cinematic sci-fi battle. In reality, it’s a scene of birth; in this single image, astronomers have captured every stage of star formation playing out at once.

This new James Webb Space Telescope (JWST) image reveals OMC-2, a beautiful and dense star-forming region within the Orion Molecular Cloud. It places viewers inside a turbulent cosmic nursery, where gas, dust and newborn stars are all in motion.

Just south of the famous Orion Nebula, one of the best-known stellar nurseries in the night sky (located within the three-star asterism known as the Sword of Orion), OMC-2 is a cloud of cold gas and dust where protostars — very young stars still gathering mass — are forming.

The scene is filled with layered clouds of gas and dust glowing in blue, green and yellow. Thick clumps of cold dust appear dark brown to black, blocking light completely and creating dark pockets across the field. Inside some of these clumps, stars may still be forming, hidden from view inside thick cosmic cocoons.

Scattered throughout the clouds are fully-formed stars of different colors and sizes, from small orange points to larger white and blue stars shining through the haze.

But perhaps the most striking feature of the image is the network of pale, glowing streams and wave-like structures cutting through the cloud. These are created by protostar jets as they collide with the surrounding material, carving out bright ridges and shock fronts. The result is an image that looks sculpted, with curved streams of whitish gas marking how young stars shape their environment.

Each jet, ridge and shadow provides clues about the movement of material through the region and helps astronomers trace how stars form and how their energy changes the surrounding cloud. Its colors and textures reveal a complex environment where gravity pulls material together, young stars ignite and energetic outflows reshape the cloud that gave rise to them.

It’s a vivid portrait of cosmic creation made possible by JWST’s infrared vision, which allows it to peer through thick layers of gas and dust that block visible light. By detecting that infrared light, astronomers can see structures and embryonic stars that would otherwise remain secret.

OMC-2 is one of four parts of the Orion Molecular Cloud, a massive filament behind the Orion Nebula. OMC-1 sits immediately behind the nebula, OMC-2 and OMC-3 are to its north and OMC-4 lies to its south.

See more Space Photos of the Week

The Amazon is the largest rainforest in the world, spanning more than 2 million square miles (5.2 million square kilometers) — an area 12 times the size of California. It influences global water cycles, stores years of global carbon emissions, supports 47 million people, and is home to the greatest concentration of biodiversity on Earth.

But the Amazon rainforest is also disappearing, with 17% of it already cut down or destroyed and largely replaced with agriculture. Other grave threats, such as oil drilling and illegal mining, continue to whittle it down. The next century may have outsize importance, as the forest could reach a "tipping point."

So what will the Amazon rainforest look like in 100 years?

The answer depends on a number of compounding threats, Bernardo Flores, a researcher with the EqualSea Lab at the University of Santiago de Compostela in Spain, told Live Science.

Encroaching farmland and organized crime are a couple of the problems chipping away at the Amazon. But those work in tandem with what he considers the three main threats: climate change, which can lead to extreme weather events, "like wetter wet seasons and drier dry seasons," deforestation and fire.

As the Amazon loses more of its forest, it triggers a feedback loop. "You have less rainfall; then you have less forest, [then] less rainfall, less forest," Flores explained. "That ultimately leads to "a global scale feedback involving the Amazon: More forest loss [leads to] more global warming. More global warming, more forest loss."

As forests get drier, it becomes easier for wildfires to burn more areas. Roads also degrade the forest, and "wherever you have roads, you have people doing illegal activities, illegal logging … then this leads to [more] forest fires," Flores said.

The "arc of deforestation" — a roughly 310,000-square-mile (800,000 square km) border along the Amazon considered the largest deforestation frontier in the world — offers a preview of what much of the Amazon could ultimately look like, according to Flores. The forests that remain there have higher tree mortality and more canopy gaps, and they are often "covered with lianas," or woody vines, that become an ecological problem, he said. Lianas compete with trees for light and nutrients in the soil, and significantly reduce not only a tree's chance of survival but also the overall diversity of trees in a forest. "When the whole forest is covered in lianas, you don't see the forest anymore," he added.

Invasive grasses introduced by cattle farmers will likely proliferate in the decades ahead, but "only a few parts" of the Amazon could become "a savanna, because a savanna is a native, biodiverse ecosystem," he said. Invasive grasses "exclude native species, reduce biodiversity" and would not allow native savanna grasses to replace the forest, Flores said. Instead, one possibility is a "degraded open-canopy ecosystem," where native, naturally fire-tolerant trees, combined with invasive grasses, vines and ferns, proliferate, Flores told Live Science.

Wildlife would quickly be affected as well. Aquatic species are especially vulnerable, Flores said. "When you start having these droughts that will simply last for one, two, three years," wetlands will dry out and become flammable, he explained. That could lead to "very quick extinctions in those areas."

The destruction of the Amazon rainforest would be disastrous for the Indigenous people living there, Christian Poirier, program director of Amazon Watch, an environmental and Indigenous rights advocacy group, told Live Science. "Imagine having your backyard bulldozed and your water source poisoned," he said. "You probably need to move from where you live, and that's exactly what's happening in the Amazon."

A devastated Amazon would also lead to "a more chaotic global climate system," Flores said. There could be less rainfall across parts of South America, and global warming will worsen. Earth could eventually reach a tipping point where ice sheets melt, ocean currents malfunction and the collapse of the Amazon accelerate warming all at once, pushing the planet to "cross the tipping point and transition to a much warmer climate," he said, leading to potentially irreversible consequences.

Unlike other major climate risks, such as the potential of the Greenland Ice Sheet melting and contributing to sea level rise, deforestation can in theory be reversed more easily by reforestation, said Arie Staal, an assistant professor of ecosystem resilience at Utrecht University in the Netherlands.

"That gives us a knob to turn that we don't have for other possible tipping points on Earth," he told Live Science. "It is clear that we really need to stop deforestation in the Amazon. And there's hope."

Editor's note: This article was updated at 6:23 p.m. EDT on June 22 to fix the conversion of roughly 310,000 square miles to 800,000 square kilometers.

Rainforest quiz: Can you sort the largest rainforests on Earth?

For most people, a minor cut or scrape is no big deal — the body heals itself quickly, and antibiotics can deal with any infections. But some wounds, such as severe burns and diabetic ulcers, are prone to bacterial infections that can become resistant to antibiotics.

"Diabetic wounds are very difficult to heal and people live with these wounds for pretty much the rest of their life," says Vitaliy Khutoryanskiy, a materials scientist at the University of Reading in the United Kingdom.

To address this problem, scientists are developing new ways to treat infected wounds using specially designed nanomaterials that are activated with light and deliver precise antimicrobial action. The approach has shown promise in reducing infection and accelerating wound healing in experiments on mice and pigs but has not yet been tested in people.

Chronic, non-healing wounds offer ideal conditions for the formation of resilient biofilms, which delay healing and significantly raise the risk of amputation. The vast majority of such wounds — over 78 percent — have these stubborn layers of bacteria, which are often antibiotic-resistant.

The new light-activated nanomaterials offer a different way to eradicate bacterial infections, by converting light into localized heat, or by reacting with oxygen present in the tissues to produce toxic molecules that kill bacteria with minimal damage to the surrounding tissue.

Our skin can naturally absorb tiny amounts of radiation but with the help of specially designed nanomaterials, says Zhenpeng Qin, a materials scientist at the University of Texas at Dallas, "you can heat the tissue to a higher temperature." The heat weakens the bacteria and helps with tissue repair. Qin, who coauthored an exploration of the technique in the 2024 Annual Review of Biomedical Engineering, notes that similar, light-triggered therapies have been used to deliver toxins to target certain skin and esophageal cancers, but they have not been applied extensively to wound care.

In one promising study with wounds, Raffaele Mezzenga, a materials scientist from ETH Zurich, and his colleagues began with a naturally occurring antimicrobial protein called lysozyme, which was extracted from egg whites. They engineered the protein into a gel mixed with a light-absorbing dye. In the presence of near-infrared light, the dye heats up, melting the gel and releasing active lysozyme. When the light is turned off and the material cools, the lysozyme reverts to its inactive form.

When the team applied the gel to wounds in mice and pigs, they found it eradicated more than 95 percent of the bacteria present. The wounds also healed more quickly, because the lysozyme — which is toxic for healthy cells, too — was activated in the wound only when irradiated with light, saving the skin from overexposure. To boost healing still further, the team added magnesium ions to the gel, which prime immune cells called macrophages to shift from an inflammatory state to one that promotes healing. "The healing will be much faster because you kill the bacteria and heal the wound at the same time," says Mezzenga.

Since bacterial biofilms are especially persistent on the surfaces of medical implants — where they can cause recurring infections and sometimes require repeated surgeries or even amputations — the team also tested their gel on infected prosthetic joints in mice. They injected the gel around an infected implanted needle and shone near-infrared light through the skin. The treatment cleared biofilms and eradicated about 99 percent of bacteria around the implant, while preserving bone tissue.

In another recent study, scientists from Gannan Medical University and Shanghai University in China treated wounds using a nanomaterial made of gold nanoparticles and graphene-oxide "quantum dots," which are tiny, carbon-based semiconducting particles. When irradiated with blue light, the gold particles absorb the light energy and convert it into heat, while graphene oxide helps to transfer electrons across the material. This boosts reactions that produce toxic, unstable molecules called reactive oxygen species that react with structures on bacterial membranes and destroy them.

When the scientists added this material to a bacterial solution and shone blue light on it for 10 minutes, the mild heat and reactive oxygen species worked together to cause bacterial membranes to disintegrate. Using a stain that distinguished dead from living bacteria, the researchers confirmed that the treatment had killed 97 percent of the bacteria.

Testing the nanomaterial in mice revealed that after nine days, the wounds on treated mice showed 99 percent healing, while those of untreated mice showed only about 70 percent healing.

While these techniques have shown promise in the lab, further work will be needed before they can be applied to people. "There is still some way to go," says Lars Kaestner, a biologist at Saarland University in Germany. To be useful in a clinical setting, he notes, researchers would need to do extensive safety testing and lower the cost of the nanomaterials.

Nevertheless, the idea provides hope for patients with chronic wounds that fail to heal with conventional antibiotics, particularly as drug-resistant infections become more common in hospitals and diabetic care.

"It's a good concept," says Qin. "Wound healing and antibacterial resistance are very big challenges. And I think any advance that we can make in these areas would be welcome."

This article originally appeared in Knowable Magazine, a nonprofit publication dedicated to making scientific knowledge accessible to all. Sign up for Knowable Magazine's newsletter.

Pets form an important part of many people's lives, providing meaningful companionship. However, our pets can sometimes also be a source of unwelcome pathogens and diseases, particularly if they frequently roam outdoors.

We are ecologists and a veterinarian who study wildlife health and the movement of pathogens among wildlife, domestic animals and people. If you let your cat outdoors, or if outdoor cats visit your yard, our recent findings may be relevant.

Zoonotic pathogens are organisms that can infect both animals and humans. From a pathogen's perspective, humans are just another animal host. Wildlife is often emphasized as a source of emerging disease for humans because there are vastly more wild animal species than domestic animal species.

However, even if a pathogen is capable of infecting people, it needs a way to reach us. Humans share more zoonotic pathogens with domestic animals than with wildlife, because domestic animals live close to us. Pathogens benefit even further if they can infect a companion animal.

In our newly published research, we compiled data from more than 400 studies to investigate how a cat's lifestyle, whether they're mostly indoors, outdoor-roaming or feral, affects that cat's likelihood of carrying pathogens that can infect people.

Across this compilation, there were nearly 100 pathogens detected in cats that are considered zoonotic and capable of infecting humans. Familiar examples are rabies, Toxoplasma gondii, roundworms and Salmonella.

Our research

We found that outdoor-roaming pet cats had three to five times the odds of carrying a zoonotic pathogen compared with indoor-only cats. More surprisingly, cats allowed to roam outdoors had similar odds of carrying at least one zoonotic pathogen as feral cats. Outdoor-owned cats carried fewer types of pathogens than feral cats, but the same pathogens that infect feral cats can also infect owned cats.

These risks become a large-scale problem because pet cats that roam freely interact closely with people, wildlife and other domestic animals. Across the studies we reviewed, about 60 per cent of owned cats had unsupervised outdoor access; in some regions, that rate exceeded 90 per cent.

Roaming cats hunt, interact with wildlife or other domestic animals, and move through environments contaminated with pathogens and toxins. Research suggests that cat owners may underestimate hunting by around 80 per cent, meaning that many prey captures and animal contacts go unnoticed.

These interactions are not uncommon and not limited to so-called pest species. Single-country estimates of wildlife killed by cats run into the billions, with more than 2,000 wildlife species documented as prey for domestic cats.

Cats hunt animals that can carry zoonotic pathogens, including rodents, birds and bats, many of which would otherwise have little direct contact with people. Owned cats might bring home rodents carrying viruses, and there are documented cases of cats bringing rabies-positive bats into homes. A cat returning home with prey can therefore create a pathway by which pathogens circulating in wildlife populations reach people.

In addition, it is not only owners who are at risk. Outdoor cats defecate in gardens, parks, playgrounds and other shared spaces, potentially leading to high contamination rates. One study estimated that outdoor cats deposited more than 60 tonnes [60 tons] of feces per 10,000 households each year.

Depending on the parasite, feces can contain hundreds to hundreds of thousands of parasite eggs that can persist in soil or water for months to years, which can infect people or other animals that come in contact with those eggs.

What cat owners can do

The most straightforward intervention is also the most economical and humane: prevent unsupervised roaming. That does not mean denying cats access to the outdoors. It can mean building "catios" or enclosures, leash walks, supervised time outside or other forms of contained outdoor access.

Veterinary care still matters. Treating existing parasitic infections and vaccinating against diseases like rabies are essential precautions, even for indoor cats. Since neither vaccines nor anti-parasitic treatment cover the full spectrum of wildlife-associated pathogens, managing exposure remains the more comprehensive protective approach.

The free-roaming debate is often framed as a false choice: either cats roam freely, or they are deprived of a natural life. That framing is misleading and inconsistent with how we manage other companion animals.

We do not assume dogs need unrestricted access to roads, neighbors' yards or to hunt wildlife to have good welfare. Indoor cats and cats with supervised outdoor access can live healthy, enriched and longer lives.

Policies and strategies that address how and where owned cats roam outdoors can help safeguard biodiversity, feline and wildlife welfare and public health. That is the central insight of One Health, that the same choices that protect ecosystems can also protect the animals and people who share them.

This article was co-authored by David Lapen, who works for and receives research funding from Agriculture and Agri-Food Canada.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

How much of a cat fan are you? Find out by taking our cat quiz!

This week's science news was filled with things missing and found, with the revelation of the first-ever deep-sea footage of the elusive goblin shark making waves in the press.

Goblin sharks (Mitsukurina owstoni) are mysterious, deepwater creatures that have not changed much since they first appeared on Earth 125 million years ago — making them "living fossils." But capturing a recording of the sharks in their deep habitats is exceptionally difficult, and they have previously been seen alive only after being hooked to the surface on fishing lines. Scientists recently filmed not one, but two goblin sharks: The first near Jarvis Island in the South Central Pacific, and the second 6,550 feet (1,997 meters) deep in the Tonga Trench.

If you like your elusive animals on the wilier (and certainly much cuter) side, we also reported on the first ever photographs of the dwarf fox, a species that was believed to be extinct but has been found near a highway in Cozumel, Mexico.

Elsewhere, archaeologists found a second cannonball from the 1836 Battle of the Alamo, meaning they now have one from each side of the conflict. And separate teams of archaeologists discovered the remains of a prehistoric man in Germany who may have been a human sacrifice and signs of a "prototype" Stonehenge close near the famous Stone Age monument.

If you got this far wondering if the "missing" news items were, well, missing, we also covered how a "cold blob" of absent heat in the Atlantic Ocean is shifting Indian summer monsoons, threatening over one billion people; the Texas-size chunk of ice missing from Antarctica; how an ancient chunk of the moon found in Africa hints at a calamitous lunar collision; and a bizarre viral infection that left a woman unable to recognize her own father.

California is scarily close to a major quake

'The system is critically stressed': San Andreas and San Jacinto faults scarily close to major earthquake, study finds

The next major Californian earthquake could be closer than we thought, according to an alarming new study.

The research, based on historical modeling of earthquake activity, found that Southern California's San Andreas and San Jacinto fault systems are at their highest levels of tectonic stress in more than 1,000 years; while also being connected by a "gate" system that could make them rupture together.

The exact odds of each event happening and the timing of a possible future rupture are unknown. But the scientists stress that understanding how much strain is building up inside the system could help to prepare for whatever comes next.

Life's Little Mysteries

Why does it take our eyes so long to adjust to the dark?

Our eyes are remarkably adaptable, switching from navigating under bright lights to the near pitch-black of a moonless night. But anyone who's stubbed a toe during this acclimation window — and that definitely includes me — may have once or twice asked themselves why it takes our eyes so long to adjust to the dark. Live Science shed a bit of light on the question.

—If you enjoyed this, sign up for our Life's Little Mysteries newsletter

Physicists split a photon

'A mixture from zero to infinity': Physicists split apart a photon — and ended up with an improbable swarm of particles

What do you get if you split a photon? Anywhere from zero to an infinite number of more photons, physicists say.

That's the finding made by a new experiment that simulated a photon being sliced by a shutter under various circumstances, revealing the result was anywhere from zero to one to upwards of an infinite swarm of the tiny light particles. The probability of each of these states corresponded to how quickly the shutter cut the photon.

And the unexpected behavior has some truly profound implications for how we view fundamental particles.

Discover more physics news

—The world's first nuclear clock just ticked on — and it could help detect a fifth fundamental force of physics

—NASA's experimental X-59 jet breaks sound barrier twice, reaching Mach 1.4 in step toward 'quiet supersonic' technology

—Earth-based telescope shares image of Artemis II capsule near the moon — one of the farthest photos of humans ever taken

Also in science news this week

—'A completely different story': 300 million-year-old fossils reveal the first vertebrate land dwellers weren't what we thought, researchers claim

—Oldest known plague victims found in a 5,500-year-old burial ground in Siberia — and many of them were children

—Indonesia's near-identical, 'Twin Peaks' volcanoes form striking mirror image — Earth from space

—Lavish Roman villa discovered outside Rome's walls may have been frequented by Hadrian and Marcus Aurelius

—Neuroscientists are searching for the 'cellular substrate of loneliness'

Science Spotlight

'River in the Sky': China's doomed plan to create a 'cloud seeding corridor' tells us how far the country will go to solve its climate crisis

China's response to the climate crisis continues to astonish. Over the past two decades, the world's industrial powerhouse has presided over the largest and fastest clean energy buildout in modern history, while also working to bring its carbon emissions to a peak before 2030.

But an underdiscussed aspect of China's climate plans are its bold attempts to geoengineer the environment to be more resilient and better suit human needs. That's why, in his three-part "Taming Nature" series, Live Science's production editor James Price investigated the country's efforts to create a permanent atmospheric river and build the world's biggest dam in earthquake-prone Tibet.

Something for the weekend

If you're looking for things to keep you busy over the weekend, here are some of the best news analyses, crosswords, interviews, opinion pieces and quizzes published this week.

—A secretive Chinese probe has just arrived at one of Earth's 'quasi-moons' and will soon attempt a first-of-its-kind landing [News analysis]

—Dangerously hot and humid: Rising temperatures in the US make outdoor exercise hazardous [News analysis]

—'Is having two legs useful' in space?: Astronaut John McFall explains what life in orbit might be like for the first physically disabled person in space [Interview]

—'They reliably chose the statistically more favorable option': A crow researcher explains how these winged geniuses process numbers, and what it could reveal about human math smarts [Interview]

—Bow-Wow, Ding-Dong, Pooh-Pooh: Expert explains early theories of how human language evolved — and their silly names [Opinion]

—Rainforest quiz: Can you sort Earth's largest rainforests from biggest to smallest? [Quiz]

—Live Science crossword puzzle #48: Largest fish on Earth — 6 across [Crossword]

Science video of the week

Watch bison herd defend a newborn calf from wolf attack in a primeval Polish forest

European bison (Bison bonasus) are typically considered to be a non-prey species — only being hunted by humans.

But rare and unexpected camera trap footage from Poland's Bialowieza Primeval Forest (the oldest and best-preserved temperate lowland forest in Europe) has called that into question.

In the video, a herd of bison is recorded rallying around a newborn calf to fend off an attack from five wolves (Canis lupus), successfully driving the predators away. It's a nerve wracking watch, and one that could become more common as wolf packs grow in size thanks to a late 1980s hunting ban across the region.

Follow Live Science on social media

Want more science news? Follow our Live Science WhatsApp Channel for the latest discoveries as they happen. It's the best way to get our expert reporting on the go, but if you don't use WhatsApp we're also on Facebook, X (formerly Twitter), Flipboard, Instagram, TikTok, Bluesky and LinkedIn.

The patient: A 31-year old man in Louisiana

The symptoms: When the patient reached the hospital, he was bleeding from the mouth and had severe neck pain and stiffness. Upon examining the man, his doctors noted a tear in the back of his throat on the right side.

What happened next: The man, a sports fisherman, had been brought to the hospital by boat and helicopter after an accident during an ocean fishing trip. He had caught a white marlin (Kajikia albida), a type of large fish with a long pointy "bill," weighing approximately 60 pounds (27 kilograms). This species can grow up to 180 pounds (82 kg).

As the man leaned over the side of the boat to release the hook from the fish, it jumped and struck him in the mouth with its bill, sending the man tumbling backward into the boat. He felt pain in his neck, which then radiated into his spine.

At the hospital, an X-ray of the man's upper spine did not reveal any abnormalities. However, his intensifying spinal pain and neck stiffness prompted one of the doctors to order a computed tomography (CT) scan of the same area. In the CT scan, physicians noted "a wedge-shaped, hyperdense object," they wrote in a report of the case. The object had penetrated the back of the man's throat and entered his spinal canal. It stuck there, piercing the foramen magnum — a large hole at the base of the skull that the spinal cord passes through.

The diagnosis: The doctors immediately performed surgery on the man to remove the penetrating object. They administered general anesthesia, and the surgeon used retractors — instruments that hold wounds open — to expose the object, which turned out to be the broken tip of a fish bill.

The treatment: The sharp bill fragment was so firmly wedged in the man's skull that the surgeon had to make an additional incision above the man's topmost vertebra in order to remove it, pulling it out along the path of entry. It measured about 1.4 inches (3.5 centimeters) long.

After the fragment was removed, the patient was given five different types of antibiotics both to prevent infection from microbes found in the throat and from bacteria that are unique to marine environments. He was discharged eight days later and continued to take multiple antibiotics for the next two weeks.

At his final follow-up visit, the man had fully recovered and showed no lingering neurological symptoms.

What makes the case unique: In 1848, doctors published the first medical case study of a skull injury from a foreign object: a gunpowder explosion had sent an iron bar through the skull of railroad worker Phineas Gage. Gage recovered, but he exhibited personality changes that doctors attributed to his significant brain injuries.

In another notable case, published in 1895, a man had tripped and fallen face-first onto an oilcan. The spout penetrated his cheek and became stuck at the base of his skull, causing temporary incontinence and permanent memory loss.

Since those 19th-century cases, physicians have reported instances of cranial trauma in different parts of the skull and from a variety of objects, including a crochet hook, a pitchfork, a bike key and a harpoon.

This man's case is the first reported instance of an injury to the foramen magnum, as well as the first injury caused by a fish bill, according to the report.

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

It's after dark, and the lights go out; a thunderstorm has knocked out your power. At first, it's pitch-black. But slowly, after a while, the light from the moon makes it possible to see your surroundings. The light didn't change; your eyes did.

But why does it take our eyes so long to fully adjust to the dark?

It has to do with the types of cells in the eye and how they evolved, experts told Live Science.

Our eyes use two kinds of cells to sense light. These cells, known as photoreceptors, are called rods and cones, based on their shapes, Alapakkam Sampath, a retinal neuroscientist at UCLA, told Live Science.

Cones are responsible for color vision. Humans possess three kinds of cone cells, which detect red, green or blue light. The colors people can see are a mix of red, green and blue, Anand Swaroop, chief of the Neurobiology Neurodegeneration & Repair Laboratory at the National Eye Institute, told Live Science.

Rods cannot discriminate colors, but they are far more sensitive to light. Each is capable of detecting a single photon, or particle of light. "Rods are what allow you to see in dim light," Swaroop said.

The extraordinary sensitivity of rods has a price, though: Once each rod detects a photon, it can take up to an hour for it to regenerate its ability to see light, Johan Pahlberg, chief of the photoreceptor physiology group at the National Eye Institute, told Live Science.

The compound that helps rods sense light is called rhodopsin, which is derived from vitamin A, Sampath said. Once each rhodopsin molecule absorbs light, it gets "bleached," meaning it can no longer detect light.

Specifically, rhodopsin is made of two compounds: opsin and retinal, Pahlberg said. When rhodopsin absorbs light, the retinal changes from bent to straight and detaches from the opsin. This retinal eventually makes its way into a part of the eye known as the retinal pigment epithelium, where it can get repaired and resume a bent shape. This retinal can then make its way back to an opsin and reattach to create a functional rhodopsin.

If all of the rods in a human eye are bleached, it may take 45 minutes to an hour for all of them to regenerate, Pahlberg said. However, some rods may regenerate within 10 to 15 minutes to grant some level of vision in dim light, he added.

Rods and cones line the retina, the back part of the eyeball. Rods outnumber cones in most mammal retinas. "In each human eye, there are roughly 6 million cones and 100 million rods," Swaroop said. Sampath noted that "since it takes a lot of time for rods to regenerate, your eyes have a huge number of them to compensate."

Cones are found mostly in the center of the retina, where the eye's lens focuses most of the light it receives, while rods dominate the rest of the retina, Sampath explained. This reflects how during the day, we rely mostly on cone cells for our vision. "Rods are mostly not functional at all during that time," he said.

The human eye does have a quicker way to adjust somewhat to the dark. It can enlarge the pupil, the dark hole at the front of the eye, to let in more light, explained Mark Fairchild, professor of color science at the Rochester Institute of Technology in New York, in an article in The Conversation. However, the vast majority of the eye's adaptation to darkness is due to its rods, and the long amount of time it takes for rods to regenerate explains why it takes so long for eyes to fully adapt to the dark.

Before artificial lighting, humans would typically not experience quick shifts from light to dark. Instead, the ability for human eyes to adapt to the dark would have relied on the setting of the sun, which might take about the same time as rod cells take to regenerate. "There was no evolutionary pressure for it to be faster," Sampath said.

Rods are the most vulnerable cells in the retina to disease and dysfunction, Pahlberg said. This is why older adults often have trouble driving at night. "My colleagues are developing a diagnostic test as a normal part of an eye exam to measure the human adaptation to the dark to see how it changes with age," Sampath noted.

A camera trap in an ancient Polish forest has captured extremely rare and unexpected footage of wolves attacking a bison herd made up of adults, youngsters and a newborn calf, a new study shows.

The event took place on Sept. 15, 2025. Five wolves (Canis lupus) enter the camera frame, closely followed by three bison cows and the newborn calf. In the footage, the cows chase after the wolves, leaving the calf alone and exposed. The wolves then surround the calf, bite its neck and try to drag it away, but two cows come to its rescue. The wolves return and seize the calf a second time in the background of the video — however, this time the entire bison herd comes to its defense to end the attack.

The clip is from the Bialowieza Primeval Forest, the oldest and best-preserved temperate lowland forest in Europe, which hosts the world's biggest population of European bison (Bison bonasus). The forest covers 350,600 acres (141,900 hectares) on the border between Poland and Belarus. There are more than 870 bison on the Polish side, according to the new study, while the Belarussian side has roughly 730 bison.

Also known as "the king of the forest," the European bison is typically considered a non-prey species, meaning it has no predators except humans. But the footage calls this into question.

"To our knowledge, we present the first video-recorded evidence of wolves attacking a European bison herd in the Białowieża Primaeval Forest," researchers wrote in the study, published May 29 in the journal Ecology and Evolution. "Although the video did not capture a direct kill, it suggests that other attacks on European bison could potentially be successful."

Historical documents show that wolf attacks on European bison used to be more common, with about 8 kills recorded annually in the Bialowieza Primeval Forest between 1840 and 1849. The forest was a popular hunting ground for monarchs from the 14th century onward, explaining why such detailed records exist.

European bison went extinct in the wild in 1919, but they were reintroduced in the Bialowieza Primeval Forest in 1952. The first confirmed bison kill since then dates to the mid 1990s, and after that, it seems as though wolves stuck to a diet of roe deer (Capreolus capreolus), red deer (Cervus elaphus) and wild boar (Sus scrofa), likely because these are much easier prey than bison, the researchers wrote in the study.

But now, "our observation demonstrated that the European bison is in fact a potential prey for wolves," they wrote. "This raises questions about why predation attempts are so rare, whether the bison can still be described as a non-prey species, and what this could mean for conservation and management of the species."

An intriguing trend in the Bialowieza Primeval Forest is that wolf packs are growing in size, possibly thanks to a late 1980s hunting ban. This shift could increase wolf predation on bison in the future, because bigger packs can handle bigger prey.

"If predation on European bison, specifically young animals, occurs more frequently than previously assumed, wolves could play a small but potentially important role in the natural regulation of bison numbers," the researchers wrote in the study. "In turn, such regulation could possibly lead to mitigation of human-bison conflicts."

High estrogen in the brain's memory center may worsen one's resilience against traumatic events, swaying the tendency to develop memory problems or post-traumatic stress in the aftermath, a recent study in mice suggests.

The research, published in April in the journal Neuron, explored the effects of estrogen in the mouse brain. It zoomed in on the hippocampus, a key part of the brain involved in learning and memory. Both male and female mammals produce significant amounts of estrogen in the hippocampus, despite it often being framed as a "female" hormone.

"We're so biased to think of female high estrogen, male low estrogen," said study co-author Elizabeth Heller, an associate professor of pharmacology at the University of Pennsylvania Perelman School of Medicine. But "in this local brain region, where you have local production of estrogen, actually sometimes the males are higher than the females depending on the female's cycling," Heller told Live Science. Estrogen levels in the female hippocampus rise and fall in line with the body-wide hormone cycle, while its levels in the male hippocampus remain fairly steady.

The study suggests that these local estrogen concentrations may influence one's vulnerability to memory problems following major acute stress. Although the research was conducted in mice, the authors think it likely has relevance to humans.

"I think this is highly translatable," study senior author Dr. Tallie Z. Baram, a professor, developmental neuroscientist and child neurologist at the University of California, Irvine, told Live Science.

Estrogen isn't always a memory booster

Traumatic experiences can cause memory disturbances, including difficulty remembering specific personal experiences and having fearful reactions to formerly safe, familiar situations. When these issues persist and are accompanied by intrusive memories of the traumatic event, they are classified as post-traumatic stress disorder (PTSD).

About 10% to 12% of women experience PTSD in their lifetime, compared with 5% to 6% of men. Some of that difference may stem from variance in men's and women's lived experiences; for instance, women have higher rates of sexual assault at young ages than men do. Biological differences between women and men are another potential factor, but their contribution to the phenomenon is poorly understood.

The new study highlights hippocampal estrogen as one difference that might matter. "The research has uncovered important new avenues for research on PTSD," Victoria Luine, a professor emerita of psychology at Hunter College in New York City who wasn't involved in the work, told Live Science in an email.

In the study, researchers simulated acute traumatic events by exposing lab mice to multiple stressors at the same time, including bright lights, loud music and the odors of other stressed-out mice. They ran the mice through various memory tests before and after the stressful experience and compared these rodents with a group that did not experience such stressors.

Compared with unstressed mice, the stressed-out male mice performed worse on the various memory tests, and those deficits persisted for weeks. "Even a month later, they had a memory deficit — so it's a really perseverative effect," Heller said.

A similar pattern was seen in female mice that were stressed out during proestrus, the phase of their hormone cycle when estrogen peaks and the body prepares for ovulation. Both sets of mice learned to associate certain cues with the stressful experience and avoid them, with females being more sensitive to those cues than males were.

But interestingly, female mice that were stressed during estrus, when estrogen plummets and ovulation occurs, showed resilience. Their behavior and memory remained comparable to those of unstressed mice. "The female mice that had low levels of estrogen laughed it off — they were completely protected," Baram said.

Studies suggest hippocampal estrogen levels are similar in male and proestrus female mice, while estrus females have lower levels. The researchers confirmed this using a technique called mass spectrometry, finding that estrus mice had half the amount of hippocampal estrogen that the males and proestrus females did.

In this context, that lack of estrogen in the hippocampus appeared to guard against the negative effects of stress. This finding was surprising, Baram noted, because estrogen is generally thought to promote memory function in both sexes and declines in estrogen, as seen during menopause, are tied to memory problems. That said, menopause takes place over a much longer timeline than the female mouse hormone cycle, which takes only four or five days.

A connection to DNA

Why do estrogen levels matter for memory? "Estrogen receptors directly control gene expression," Heller said. By binding to its receptors, estrogen turns the activity of certain genes up or down.

Heller's lab studies mechanisms that control gene activity in the context of psychiatric disorders. One of those mechanisms is chromatin remodeling, meaning changes in how DNA is packaged in a cell that can shift which genes can be activated at a given time. A portion of the chromatin can be "open," exposing genes to machinery that turns them on, or "closed," which typically shuts genes down.

It turns out that the high hippocampal estrogen in male mice and proestrus female mice opens up their chromatin in a way that might leave them vulnerable to memory issues ushered by severe stress. Female mice in estrus, by contrast, have a totally distinct chromatin profile that appears to be protective.

"We can see that the function of many of those [open] genes relates to synapse biology," Heller said. Synapses are the points at which different neurons meet and exchange electrical signals, and they're central to the physical structure of memories in the brain.

It may be that, in most circumstances, it's useful to have high levels of hippocampal estrogen because they "open" the chromatin, enabling the hippocampus to forge new memories quickly in response to new experiences, Baram noted. But when these experiences consist of severe acute stress, "that same plasticity, that same ability of the brain to learn, turns problematic," she said. If the results carry over to humans, women may be particularly vulnerable to these memory impacts in certain phases of their menstrual cycles or points in their lifespans when estrogen is high.

In males and females, different flavors of estrogen receptor were responsible for the stress-induced memory issues. The reasons for this difference will be a matter of future study, Baram said. Additionally, future research could attempt to pinpoint exactly where the different estrogen receptors are located throughout the hippocampus, Heller said.

The study provides a "strong demonstration that estrogens drive sex-dependent, stress-induced changes in chromatin networks which can dramatically alter neural functions like memory," Luine said. What's more, "these results present cogent evidence that sex is a powerful biological variable."

Historically, female lab animals were excluded from studies because it was thought that their hormone cycles were too complex and would muck up the findings. The field of neuroscience exemplified this trend. In recent years, the U.S. National Institutes of Health (NIH) has required that scientists take sex differences into account when designing NIH-funded human and animal studies, but progress has been slow on both fronts — and current federal leadership has signaled a lack of support for the initiative.

It's important to include both sexes in research to truly understand how the brain functions and responds to external factors, like stress, Luine said. "An important aim of this and other studies is to protect humans against PTSD," she added, and this study strongly suggests preventive treatments for PTSD might need to be tailored by sex.

Beyond PTSD, Baram thinks the research could have implications for women's risk of aging-related memory problems and dementia.

The decline of estrogen in menopause is thought to raise this risk, but prior to menopause comes perimenopause — a period with massive spikes in estrogen. The study's findings hint that if stress shows up during perimenopause, the combination of stress and high estrogen levels may contribute to memory problems. Thus, perimenopause may represent another time when women are particularly vulnerable to memory disturbances, Baram suggested.

"We need to start thinking a little bit differently," she said. "What is it about women at that stage in life that makes them more vulnerable to memory loss with aging?"

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

This article was first published May 4, 2026.

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

Never-before-seen fossils of newly hatched crocodile-like creatures are shining new light on how our aquatic ancestors conquered land.

Early four-limbed vertebrates (tetrapods), which would eventually give rise to humans, took their first steps on land in the Devonian period, some 419 million to 359 million years ago, marking one of the most important periods in the evolutionary history of animals.

Now, a new study published Thursday (June 18) in the journal Science has revealed that these early tetrapods were less like amphibians and more like us. Rather than having a tadpole phase in their development, as many amphibians do today, new evidence suggests that they were direct developers — growing from smaller to bigger versions of themselves, like their ancestors, humans and many other animals.

The study is an important contribution to our understanding of early tetrapods' reproductive developmental biology, said Tim Smithson, a visiting academic at the University of Cambridge who specializes in early tetrapods but was not involved in the study.

It suggests that the "earliest tetrapods that took those first steps on to land were able to rely on the successful reproductive and developmental strategies of their forebears," Smithson told Live Science in an email. "Direct development made life easier — one less thing to worry about!"

The new research was based partly on fossils from early land-dwelling predators called embolomeres. These animals looked like a cross between a crocodile and an eel and ruled river, lake and swamp habitats 350 million to 280 million years ago, during the Carboniferous and Permian periods. While these creatures could grow to more than 10 feet (3 meters) long as adults, the study unveils rare fossils from Mazon Creek, near Chicago, that preserved embolomeres as hatchlings that were days to a couple of weeks old.

"These are intimate details of the first moments of these animals' lives, and we've never seen that before for this entire part of the evolutionary tree," study co-author Jason Pardo, a postdoctoral fellow of evolutionary biology at Vilnius University in Lithuania and a research associate at the Field Museum in Chicago, told Live Science.

These fossils didn't show evidence of external gills and other tadpole-like features that the researchers would have expected from an early land dweller. The researchers then checked other fossils from before and during the "fin-to-limb transition" but found no evidence of an amphibian-like life cycle in those, either.

"For as long as we've understood evolution, we've assumed this story of how we made that transition from water to land," Pardo said. "We in fact have a completely different story."

Science upended?

A statement released by the Field Museum claimed that the study upends scientists' understanding of how animals conquered the land. However, the experts Live Science spoke to disagreed with this assertion.

"The Mazon Creek material is wonderful, the study is interesting and the interpretation of the fossils is sound, but I don't think the results are terribly surprising," Per Ahlberg, a professor of evolutionary organismal biology at Uppsala University in Sweden, told Live Science in an email.

Ahlberg, who was not involved in the new study, specializes in the early evolution of tetrapods. He noted that scientists knew some early tetrapods had a larval stage similar to that of modern salamanders ‪—‬ namely, those belonging to the group Temnospondyli, which he described as the ancestral stock of modern amphibians. However, he contends that this didn't mean scientists assumed every early tetrapod was the same.

"Nobody has been arguing in recent years that ALL early tetrapods had such a larval stage or that this was essential for enabling the transition to land," Ahlberg said. "I mean, I have been working right at the core of this research field for 40 years and I have never given it any thought."

In response, Pardo agreed that specialists in the field recognized that the data didn't support that early tetrapods had an amphibian-like development. However, he argued that even among specialists, assumptions were still made about metamorphosis — a major developmental transition, like a tadpole transforming into a frog — and amphibian-like bodies.

"Onto something big"

Study co-author Arjan Mann, an assistant curator of early tetrapods at the Field Museum, first saw the study's first baby embolomere fossil during a 2016 trip to the Field Museum while working on his doctorate. At the time, the fossil was a mystery.

Mann and Pardo mused over the fossil's identity for years before high-resolution scans with scanning electron microscopy at the Canadian Museum of Nature confirmed that the ancient creature was an embolomere, according to the museum's statement.

"I think Jason and I both knew we were onto something big, since fossils of this kind of animal and from this phase, and developmental state in early tetrapod evolution have never been found or studied before," Mann told Live Science in an email.

Along with the embolomeres, the researchers looked at megalichthyid fish from before the land transition and limbless, snake-like creatures known as aistopods from during the land transition. All showed signs of direct development, they said.

"I think the take home message of this study is that we should always challenge conventional wisdom in science, especially when these older ideas do not have substantial backing," Mann said.

Some people from Oceania harbor thousands of genetic variants inherited from the Denisovans ‪—‬ a mysterious group of extinct humans ‪—‬ that are still active in their immune systems today, a new study finds.

The findings, published June 11 in the journal Science, come from the largest-ever map of Denisovan-inherited DNA ever created. The discovery shows that Denisovan DNA "is not just a remnant of ancient liaisons; it continues to influence our biology today," study co-author Serena Tucci, an assistant professor of anthropology and head of the Human Evolutionary Genomics Laboratory at Yale University, said in a statement.

Experiments revealed 3,127 variants inherited from Denisovans that still function in the immune systems of modern-day people; some of these variants switch genes that turn the immune response on or off, according to the new research.

However, because many of the immune system genes identified also affect other bodily functions, it is unclear exactly how these genes benefited survival, study first author Patrick Reilly, an evolutionary genomics researcher at Yale, told Live Science.

Denisovan DNA is active in humans today

Previous research has already found that some modern-day people in Oceania ‪—‬ a region that includes New Guinea, the Solomon Islands and Fiji ‪—‬ have some Denisovan DNA. For example, people from Papua New Guinea are known to carry up to 5% Denisovan DNA in their genomes thanks to prehistoric trysts with the enigmatic group of humans who lived in Asia and disappeared around 30,000 years ago. This is among the highest proportion in the world, with modern-day East Asians typically carrying only around 0.1% Denisovan DNA.

Previous research has also shown that modern-day Tibetans carry a Denisovan version of the EPAS1 gene that supports their adaptation to living at high altitudes. People living in the highlands and lowlands of Papua New Guinea have different Denisovan gene variants depending on their local environments.

Yet Oceanians are vastly underrepresented in genomic databases. Sequencing the genomes of Oceanians can give a glimpse into the lives of the Denisovans and is essential for closing gaps in health disparities in Pacific Islanders as a whole, Reilly said.

To fill this gap, Tucci and her team sequenced the genomes of 177 Oceanians from 12 populations and compared them to 1,284 previously published genomes from populations worldwide. Then, they compared these segments to the known Denisovan genome and three Neanderthal genomes.

Combined, the team built a catalog containing three times more Denisovan genetic sequences inherited from Denisovans than were previously identified, over 70% of which were unique to Oceanians.

Natural selection increased the frequency of some of these variants in people from Near Oceania, which includes New Guinea, the Bismarck Archipelago and the Solomon Islands in the Pacific Ocean, including genes linked to bone development, metabolism and fertility.

The team also ran experiments to assess whether any of the Densiovan DNA was changing how genes behaved in these populations, Reilly said.

This revealed that Denisovan genetic variants can switch various immune system genes on or off, although the exact immune functions that were targeted varied among the Oceanic populations studied.

Early migrants to Oceania at least 42,000 years ago benefited from Denisovan genes when they entered their new environment and encountered new disease-causing pathogens, Reilly said.

"This is consistent with multiple independent instances of local adaptation in response to novel immune environments and pathogens during human dispersal into the Pacific," the authors wrote in the study.

Although the researchers don't know exactly why natural selection acted on these genes, the findings highlight the major role pathogens played in shaping the way humans and our extinct relatives evolved, Reilly said.

The research is an "outstanding effort to try to understand the biological implications" of the enduring Denisovan genetic variants, Mathilde André, an evolutionary geneticist at the Pasteur Institute in France who was not involved in the study, told Live Science in an email.

The tripling of known Denisovan-inherited genetic sequences, most of which are unique to Oceanians, highlights the need to sequence the genomes from previously unrepresented populations to capture the diversity of Denisovan DNA, André said.

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

Camera traps from inside the Chernobyl exclusion zone reveal how the occupation of Russian forces at the site in February and March 2022 altered the behavior of wildlife living in the area.

After the invasion, which involved significant armed conflict inside the exclusion zone, mammals like deer and horses became less active and spent less time moving around at night, a new study reports.

Researchers discovered the changes by comparing footage from camera traps collected during the early months of Russia's 2022 invasion with recordings from the same period a year earlier, before the conflict began. The findings, published Thursday (June 18) in the journal Science, offer a rare glimpse of how animals respond to the immediate disruption caused by warfare.

"I wish the opportunity to analyze how the unfolding invasion affected wildlife ha[d] never happened," Svitlana Kudrenko, who conducted the study as part of her PhD at the Albert Ludwig University of Freiburg in Germany, told Live Science in an email. "Unlike in preindustrial times, current interstate conflicts are highly detrimental for wildlife because of a long list of warfare, often operated remotely."

The study took place in the Chernobyl exclusion zone, a roughly 1,000-square-mile (2,600 square kilometers) area surrounding the site of the 1986 Chernobyl nuclear disaster. Following the reactor explosion, authorities evacuated the region and restricted most human activity. Over the decades, with little to no human activity, wildlife populations have flourished, turning the zone into a natural laboratory for scientists studying ecosystem recovery and animal behavior.

But in February 2022, Russian forces seized control of the region during the beginning stages of the invasion of Ukraine. Military vehicles, troop movements, weapons being fired and other wartime disturbances suddenly transformed one of Europe's most unusual wildlife refuges into an active war zone.

To investigate the impact, researchers analyzed data from camera traps already operating in the exclusion zone from 2020 to 2022. Studying the ecological effects of armed conflict is difficult because war zones are dangerous and often hard for researchers to access.

By using the existing network of automated cameras, the scientists captured wildlife responses that would have been impossible to record otherwise. In total, the team analyzed almost 2,000 photographs and videos from the exclusion zone to build a picture of behavioral changes in response to the conflict.

The images and footage revealed responses from 11 wild mammal species, ‪showing that some animals changed their behavior during periods of heavier fighting.

Several mammal species — including roe deer (Capreolus capreolus), red deer (Cervus elaphus), moose (Alces alces) and red foxes (Vulpes vulpes) — were less active during the occupation than before the conflict, especially at night, the team reported.

The findings suggest that the impact of conflict can ripple through entire ecosystems. While Russia no longer occupies the Chernobyl exclusion zone, the authors highlighted that this study still shows how animal behavior can adapt to warfare.

Camera traps could become a valuable tool for measuring the environmental costs of conflict and understanding how wildlife copes with sudden human disturbances across the globe, the researchers added.

"Our study highlights the need to develop and implement research and conservation strategies focusing on armed conflict impacts on wildlife and environment in general, especially in areas of conservation importance," Kudrenko said.

What do you know about the animal kingdom? Test your knowledge with our animal quiz!

Energy used to power artificial intelligence (AI) could jump to 3% of global electricity demand by 2030, guzzling as much water as the 1.3 billion people in sub-Saharan Africa consume in one year to meet their domestic water needs.

Those are the conclusions of a recent United Nations report that estimated the land use, water consumption and greenhouse gas emissions associated with AI's breakneck expansion. If the data centers that underpin AI formed a country, they would rank 11th in the world for energy use due to their high infrastructure and electricity needs to train ever more complicated models and satisfy users, the report found.

By 2030, data centers could rise to sixth in the world for energy consumption, which would have a land footprint the size of Connecticut and release emissions comparable to those of the U.K. in 2025, depending on how much renewable energy is in the mix.

The findings highlight how much additional pressure AI and the infrastructure that supports it could put on the environment and the climate within the next few years. But why does AI have such a huge footprint, who is benefiting or being left out from the opportunities linked to AI's growth, and what can be done to limit the damage?

To find out more, we spoke with Kaveh Madani, lead investigator for the U.N. report; director of the United Nations University Institute for Water, Environment and Health; and the recipient of this year's Stockholm Water Prize.

Sascha Pare: What would you say is the main takeaway from the report?

Kaveh Madani: The main takeaway of this report is that although in the general discourse AI is perceived as something virtual, or digital, or up in the clouds, there is [a] massive physicality to AI and the supply chains and infrastructure that back it up. And that's one thing that this report has tried to do: to remind people that behind every prompt, every use, every interaction, there is some level of impact on the environment. This is because from the top of the supply chain, where the extraction of critical minerals happens, to the point of manufacturing the hardware, the construction of the data centers, then the operation of data centers, and then dealing with the e-waste, there are major environmental impacts. If we take all of those into account, then we realize that what's digital is not necessarily free of impact. There is always some footprint associated with it, and we have to remember that.

SP: Why does AI have such massive land and water footprints, specifically?

KM: The report outlines the carbon, water and land footprints of AI's energy use. All along the supply chain, from the extraction of critical minerals to the point of disposing and dealing with the electronic waste, we have actions and interventions that require water, require land, and are associated with carbon emissions. So, if you think about, for example, the extraction of critical minerals, we know that during the process, a lot of water is being used and a lot of water is being polluted and poisoned. We published a report in April about the water injustice implications of the critical minerals, showing exactly what is happening where we have the extraction of critical minerals.

But let's not forget that the [new] report is focused on AI's energy use, and then tries to argue that the energy production process itself requires also a lot of water and land. If you are using hydropower to provide energy to your data center, you're using a lot of land and a lot of water. This applies to all sorts of energy sources, regardless of being clean or not, or if you consider them renewable or not — they all require water and land. On top of this, of course, you need to build data centers on land, but also you need water for cooling. That's why, throughout the supply chain, throughout the life cycle of AI, we have a lot of water and land use, in addition to carbon emissions.

SP: The report is packed with jaw-dropping statistics about how big AI's environmental footprint could get by 2030. But how significant are the impacts?

KM: First of all, it is very hard to estimate exactly how much energy AI is currently using, but we know that roughly 20% of the current load of data centers can be attributed to AI. We are expecting that to be 40% within a few years. And by then, the data centers that back AI's operations are expected to have an energy demand that is about 3% of the total energy demand of the world. This is equivalent to being the sixth-most-energy-intensive country in the world. The water demand of that is also huge; the water footprint associated with that is enough to satisfy the domestic water needs of 1.3 billion people in sub-Saharan Africa.

SP: Can the environment and communities cope with the projected levels of energy and water consumption needed for AI?

KM: There would be places in the world where big decisions must be made, meaning that you have to decide if you want to continue using your water for agriculture or if you want to put it into data centers. Those would be decisions for the communities — and if the communities are not involved, then the most vulnerable, the poor, will be dealing with the consequences.

At the same time, we know that the world's electricity consumption keeps increasing. That's a major problem, because although we are trying to add more and more renewables to the energy supply systems, the renewables cannot keep up with the increasing electricity demand. This means that not only can we not retire the old systems, but we might also need to use more fossil energy to satisfy this growing demand. And of course, that means more pressure on the fragile environment.

We know some of the data centers are being placed in locations that are already dry or suffering from what we refer to as "water bankruptcy," based on the report we published in January. These are major issues. More pressure on the environment [puts] more pressure on humans, and this recipe means [we could have] a kind of reinforcing degradation loop that would jeopardize both nature and human society.

SP: Who is benefiting the most from AI's expansion, and who is being excluded?

KM: AI expansion is benefiting humanity as a whole. It has changed our lifestyle; it has provided a lot of opportunities and improvements. But at the same time, it has some consequences. The issue that we see right now is that the richer communities and countries of the world are the ones that are benefiting from it the most, and within those communities and countries, it's the rich who are also profiting more from the expansion. If you look at the investment landscape of AI, you can see that there is a lot of push from a number of strong players and private investors. And they don't bear the costs when it comes to pollution, water bankruptcy, land degradation and so on.

If you think about the emissions, they are contributing to global warming, and everybody would suffer from it. Even the countries that don't have AI infrastructure are affected: If you think about where the critical minerals come from, you see a lot of poor communities, poor countries and poor regions in Africa, South America, parts of Asia, where people don't have basic infrastructure — they don't even have clean drinking water and energy infrastructure. They don't benefit from this expansion and the profits and utilities it provides. It's the most vulnerable communities and the poor economies that are going to suffer the consequences, while the other ones will benefit more.

SP: How did you estimate AI's growth by 2030, and how likely is it that your numbers will come true, given the fears that AI is a bubble that's about to catastrophically burst?

KM: We were looking at the data centers, and we still think that our projections are conservative. There is a lot of push from the private sector to further growth. Countries are also seeing investment in AI and data centers as an investment in security, sovereignty and other matters, so there's also a competition there. Some of the investments — some of the decisions about expanding AI — are not necessarily based on comprehensive assessments. Investments remain a bid to stay in the race, and that means more and more push. So we think that what we have projected is probably very conservative.

SP: China is scaling up its energy capacity together with data center buildout, and it is putting data centers in the ocean to try to solve the hardware cooling issue. What do you make of this strategy, and should other countries learn from it?

KM: China's more centralized decision-making system provides advantages, but I think we need to be careful about generalizing the information of one or two projects highlighted by the media to the overall strategy.

We know that China has been expanding its renewable energy production capacity, and that's definitely a good thing. We have to make sure that the additional load of AI would not mean more fossil energy and would not compromise the decarbonization process. But at the same time, we should note that just scaling up renewables is not sufficient if you're thinking about decarbonization. We need a massive addition of renewables if we're going to reverse climate change, and we are not seeing strong enough signs of that around the world. So that's something that we have to be worried about.

That has been the challenge created for the world because of the expansion of AI. When it comes to putting things under the ocean, I think we do not yet have enough information and enough experience to judge if those things come with less environmental impact. What we hide would not be impact-free; there are also other impacts to worry about.

SP: What are some other solutions to the pressures AI is putting on the environment and people? How should we approach the rapid expansion to ensure it is fair?

KM: We offer a framework based on a number of principles about making the AI governance system more fair and transparent and sustainable. So, those are the principles suggested, and they bring responsibility to all stakeholders, including the developers and service providers — those who provide the technology and have responsibilities of ensuring that their systems are more transparent and efficient.

Then, we have the governments that have the responsibility of ensuring that information becomes available, that footprints are properly monitored and disclosed and regulated. They can use a range of incentives, mechanisms or penalties to ensure that footprints are reduced across the supply chain — and I insist on that — from the mines to the landfill. So, that can be done; pollution taxes can be charged and so on. [Governments should ensure] that those who have to deal with the consequences also benefit from the profits and the opportunities that data centers bring to their communities. Decisions must be made based on resource availability and the environmental consequences taken into account.

Users also can do a better job of making smarter choices by using AI more responsibly and only when it's absolutely necessary. When using AI, choose the right models, and be mindful of what is happening behind the scenes. Is it really necessary to generate another image? Is it really necessary to generate a video? Is it necessary to use the model in the "thinking mode"? Together, all the stakeholders can make a difference, and users can also call for more transparency and force governments to take action to force the service providers to provide more information and be more transparent.

Editor's note: This interview has been condensed and lightly edited for clarity.

Rainforests are some of the most important and diverse ecosystems on Earth. Found across several continents, these vast forests are home to millions of plants and animal species, many of which can't be found anywhere else. Many rainforests, both tropical and temperate, also play a crucial role in regulating the planet's climate by absorbing carbon dioxide and producing oxygen.

Rainforests vary immensely in size. Some stretch across multiple countries and cover millions of square miles, while others are much smaller but still support incredible biodiversity. Understanding the relative size of these rainforests helps us appreciate their role on our planet and the challenges involved in preserving them.

In this quiz, you'll test your knowledge by sorting the top 10 biggest rainforests from largest to smallest. Click on and drag the blue rectangles to place them in the right order. Remember to log in to put your name on the leaderboard; hints are available if you click the yellow button.

Related quizzes:

Earth quiz: What do you know about our planet's most amazing features?

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Evidence of two ancient wooden posts aligned with the summer and winter solstices has been discovered near Stonehenge in southwest England. The posts have rotted away, and only traces of the postholes survive. But archaeologists say the structure predated Stonehenge, and they think it was a temporary religious monument until a permanent one was built. They even suggest it may have been a Stonehenge prototype.

Analysis suggests that ancient people used the posts to mark the summer and winter solstices, Phil Harding, an archaeologist at Wessex Archaeology who's leading the project, noted at a news conference on Wednesday (June 17).

"These people were capable of establishing the points on the horizon where the sun rises in the midsummer and sets in midwinter," he said. "This was a pioneering achievement." (The 2026 summer solstice will be celebrated at Stonehenge on June 21.)

Harding's team at Wessex Archaeology, a private firm that often works for the government and local authorities, publicly announced the finds June 18 in the U.K., and a report on their research will be peer-reviewed and published. The ancient monument consisted of the two large, wooden posts, about 400 feet (120 meters) apart, on land near the village of Bulford, a few miles east of Stonehenge.

The land is now controlled by the U.K. Ministry of Defence, but archaeologists have been allowed to excavate there since 2015. They previously found traces of two "henges" ‪—‬ rings of ditches and banks made from earth ‪—‬ and dozens of Neolithic pits from about 5,000 years ago, centuries before Stonehenge was completed. The pits were filled with animal bones, pottery, flints and charcoal, and the researchers think they date to the time that the first phase of Stonehenge was being built.

Solstice alignment

The posts were aligned to point along an axis that marked the direction of sunrise on the summer solstice, or "midsummer's day," and the setting of the sun exactly six months later, at the winter solstice, or "midwinter's day," according to a statement from Wessex Archaeology. The same astronomical alignments are seen at Stonehenge.

The animal bones and other signs of feasting in the pits at Bulford are evidence of large numbers of people gathering for religious festivals. (Signs of ancient feasting have also been found at Stonehenge.)

"When we talk about the solstice, we're talking about religion," Matt Leivers, an archaeologist at Wessex Archaeology and one of the researchers, said in the statement. "What we see at Bulford, and later at Stonehenge, is a way of celebrating and marking the passage of time, but it's also about making sure the world keeps working as it should."

The site predates the largest circles of stones at Stonehenge, which have the same alignments. "What we've discovered at Bulford is 500 years earlier than the famous stones we know so well," Harding said. The researchers even suggest that the Bulford monument may have been a sort of prototype for Stonehenge itself.

Ancient stones

Stonehenge is the world's most famous Neolithic monument, but its original purpose was long a mystery. Archaeological investigations have established that the first earthwork henge was started there about 5,000 years ago, and the famous central stones were added about 500 years later.

Recent discoveries at Stonehenge include evidence of ancient cremations, and many archaeologists now think the monument was originally a burial site. If that's the case, the alignment with sunset on the winter solstice might have represented "new life," as the days then became longer and warmer after the depths of winter. However, no human remains have been found at the Bulford site.

Susan Greaney, an archaeologist at the University of Exeter who was not involved in the research, said the new finds show the importance of the region to prehistoric people. "It is intriguing to think that simple posts were erected here to align with the solstices around 500 years before Stonehenge was built," she told Live Science.

The Bulford monument may have been a temporary "model" for Stonehenge itself, Amanda Chadburn, an independent archaeologist who wasn't involved in the research, told Live Science "If you were designing a very complicated piece of engineering like Stonehenge," she said, "you would have had to understand how to make it before starting."

See how much you know about Stonehenge with our Stonehenge quiz!

Archaeologists have discovered an iron cannonball fired by Texans at the Battle of the Alamo in 1836. This is the second intact cannonball they have discovered from the famous conflict. The first one, a bronze cannonball, was found earlier this year and was likely fired by the Mexican army.

"It's a huge deal," Tiffany Lindley, director of archaeology at the Alamo, said in a video statement from Alamo Trust. "We all thought, 'There's no way we can top it,'" she said, referring to the bronze cannonball discovered March 5, just a day before the 190th anniversary of the conflict that killed Davy Crockett, "and then we found another one."

Both cannonballs were recovered from the northeast corner of the church at the Alamo, which was originally built in 1718 as a Spanish mission and fortress in what is now San Antonio. But the Alamo is better known as the location of an 1836 battle during the Texas Revolution, in which Anglo-American settlers and Hispanic Texans known as Tejanos seceded from the Republic of Mexico.

In a 13-day siege culminating in a deadly assault on March 6, 1836, Mexican troops, commanded by Gen. Antonio López de Santa Anna, surrounded the Alamo and killed the 180 Texan rebels defending the structure, including Davy Crockett. The cry "Remember the Alamo!" was used in later skirmishes in the Texas Revolution as soldiers fought Mexican troops for independence.

The newly excavated iron cannonball was found June 2, according to a statement from Alamo Trust.

Of the two cannonballs, "the newest one is slightly larger" and was likely fired from a cannon that shot 6-pound [2.7 kilogram] cannonballs, Kolby Lanham, a senior researcher and historian at the Alamo, said in the statement. "The likelihood is that the bronze one belonged to the Mexican Army and the iron one belonged to the Texans."

Over the years, archaeologists have found numerous pieces of ammunition and shrapnel at the Alamo, Lindley said, but these cannonballs are the first examples of solid shots — spherical projectiles fired from a gun or cannon — they have ever found.

"It's just a huge kind of once-in-a-lifetime deal," Lanham said. "But obviously, it's happened twice."

The Mexican and Texan cannonballs were found near each other, so they are likely the historic remains of the two sides shooting at each other in the fateful siege nearly two centuries ago.

"Whenever they were dropped the very first time — possibly in 1836, probably — they haven't been touched since, and that's what makes them extra special," Lindley said. "I don't think you can undersell it."

The Alamo remains an active archaeological site, where experts have discovered artifacts that span its centuries of history, from Indigenous stone tools that predate the Spanish mission through the late 19th century, when the structure was converted into a general store and warehouse.

Can you identify these historical objects of war? Test your smarts with our weapons of the world quiz!

Physicists recently wondered what would happen if you tried to split a photon ‪—‬ and they found some unexpected behavior that may transform the way we think about particles.

The experiment, in which researchers simulated a photon being sliced by a shutter under various conditions, showed that a severed photon can lead to a complex mixture of zero to infinitely-many photons — raising some big questions about the nature of particle interactions.

Photons are elementary packets of light, which means they are not made up of anything else. So what does it even mean to try splitting a photon? It may be possible thanks to wave-particle duality — a core principle of quantum mechanics, the bizarre physics of the very small.

According to wave-particle duality, a photon is not only a particle but also a wave. Using theoretical calculations, the researchers investigated what would happen if you sent this photon through a shutter and closed it while the photon was passing through, effectively cutting off the tail end of the photon wave.

"I think that most physicists would expect there to be a certain probability that you have zero photons and a certain probability that you have a single photon left after you have done this," Johannes Skaar, co-author of the new study and a professor of theoretical physics at the University of Oslo, told Live Science. "And that is approximately true, but it is not exactly true."

What are the chances?

This brings up another strange aspect of quantum mechanics: its probabilistic nature. Particles exist as a cloud of probabilities stretching to infinity. Until a particle is observed, its properties, such as its position or energy, are in a superposition of possible values; all we can know are the chances of finding it in a certain state.

Through their calculations, Skaar and his colleagues determined how cutting a photon affects these probabilities. In their study, recently accepted in the journal Physical Review Letters, they found that it would create a complex mixture of photon states, including one with an infinite number of photons.

Each of these states has a probability that depends on how quickly the shutter cuts the photon. The expected number of photons becomes infinite only if the shutter is closed infinitely quickly. For realistic shutter speeds, even a thousand photons would be extremely unlikely.

This may sound very strange, but the quantum physicists were unfazed. In fact, what surprised Skaar and his colleagues was what happens if you make measurements of the cut photon from different perspectives.

"When you measure from one side of the shutter, then it will look like a single photon state," Skaar said. "Then, on the other side, it will look like a vacuum state — that means no photons. And that is very strange because the actual state globally is this mixture from zero to infinity."

Changing how we think about particles

The fact that these complex mixtures can be treated locally as very simple states raises fundamental questions about the nature of particles. Skaar said they are still reckoning with the full extent of these implications and they are now considering how this process could play out for other quantum particles, such as electrons.

They hope that by following this theoretical thread through, they may be able to develop a neater way of describing particle interactions. Currently, particles' infinite stretching means they have been interacting for an infinite amount of time. This then poses a problem for causality ‪—‬ the order of cause and effect ‪—‬ in particle interactions, the team said.

These new theoretical photons with a cutoff tail would not have this problem, meaning the causal link in an interaction would be clear, Skaar said. He admitted that there is much more work to be done to develop the theoretical description of this interaction. However, the new result is an important step toward describing particle interactions with a clear causal relationship, which Skaar described as the team's "ultimate goal."

Hunter-gatherers in Siberia fell victim to lethal plague outbreaks around 5,500 years ago, marking the oldest known evidence of plague to date, a new study finds.

A research team investigating the Stone Age remains identified ancient DNA ion over a dozen individuals that came from previously unknown strains of Yersinia pestis, a bacterium that causes pneumonic, bubonic and septicemic plague.

The disease that infected these hunter-gatherers, most likely pneumonic plague, probably spilled over from wild marmots, and ravaged through family groups living around Lake Baikal, according to the study, published Wednesday (June 17) in the journal Nature.

Ancient DNA from the two newfound plague strains revealed a unique gene that codes for proteins that trigger massive immune responses, perhaps explaining why children were the most likely to die from the disease, the authors wrote in the study.

The discovery of two deadly plague outbreaks in prehistoric hunter-gatherers challenges the long-standing assumption that epidemics first occurred after the rise of agriculture, study first author Ruairidh Macleod, a researcher of ancient genomics at the University of Oxford, told Live Science.

"We got the really striking result that we found lots and lots of plague here far earlier than we expected," Macleod said. This is "the closest we'll probably ever get to a direct smoking gun demonstrating the virulence [the ability of germs to cause disease] of these early plagues."

Plague has played an extremely important part in human history and continues to infect people today. The strain of Y. pestis that affects people today still causes epidemics, predominantly in Africa, although seven human cases, on average, are reported in the U.S. each year. Nowadays, Y. pestis cases that are caught early can be treated with antibiotics.

Understanding how the disease has evolved over time is essential for gaining insight into how Y. pestis may change in the future, study co-author Eske Willerslev, an evolutionary geneticist at the University of Copenhagen, said at a news conference Tuesday (June 16), ahead of the study's publication.

Prehistoric plague outbreaks

Research suggests that plague outbreaks devastated communities long before the Black Death, the catastrophic epidemic that swept through 14th-century Europe and killed around 25 million people, or between 25% and 33% of Western Europe's population at the time.

For example, repeated plague outbreaks have been identified from between 5,300 and 4,900 years ago in farmers from what is now Scandinavia. However, whether these early plague strains were deadly or simply caused mild sickness has been hotly debated because the bacterium lacked some known disease-causing genes.

Now, a close inspection of the ancient DNA of hunter-gatherers buried in four cemeteries along the banks of the Angara River, which flows out of Lake Baikal, has provided "the best kind of evidence that we could probably hope for" that prehistoric plague strains were lethal and resulted in mass death, Macleod said.

During previous excavations of these cemeteries, researchers noticed that an unusually high number of children had been buried over a short period. There were no signs of violence or other injuries, Macleod said at the news conference, leaving the archaeologists stumped as to why so many children died.

Macleod and his team stepped in to see if ancient DNA could shed light on this mystery.

The researchers extracted ancient DNA from the teeth of 46 individuals at the four cemeteries. They checked whether any were related while also scanning for ancient DNA from known germs.

To their surprise, they identified large amounts of Y. pestis in 18 individuals. These cases spanned two distinct disease outbreaks: one lasting from around 5,596 to 5,341 years ago, and another most likely spanning 5,126 to 4,926 years ago.

Some graves contained the remains of multiple infected individuals who were buried at the same time, suggesting they died during the same outbreak. One grave belonged to three closely related young girls, while another held a nephew and aunt.

"There must have been survivors who knew these people when they were alive and what their identities were and what their biological relationships were to bury the dead and bury them in shared graves," Macleod said.

It is currently not possible to identify plague-specific antibodies that would identify which individuals survived the outbreaks, he added.

The findings help to support the idea that prehistoric populations were impacted by plague, Aida Andrades Valtueña, a researcher who specializes in ancient pathogens at the Max Planck Institute for Evolutionary Anthropology in Germany but was not involved in the study, told Live Science in an email.

However, more complete sequencing of the plague DNA is needed to confirm that the various cases were from the same outbreak, rather than from separate infections, she noted.

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

A Chinese spacecraft has arrived at one of Earth's temporary "quasi-moons" and will soon attempt to land on the space rock to scoop up samples that will be returned to our planet next year. The ambitious mission could help researchers uncover secrets about Earth's main moon and provide clues that may benefit space exploration and planetary defense, experts say.

The Chinese National Space Agency (CNSA) probe, named Tianwen-2, launched from Xichang Satellite Launch Center in southern China on May 28, 2025, Live Science's sister site Space.com reported at the time. The car-sized spacecraft sent back its first images a few weeks later, giving us our first glimpse of its secretive design, followed by a selfie with Earth a few months later.

The mission's primary target is 469219 Kamo'oalewa — also known as 2016 HO3 or simply Kamo'oalewa — a near-Earth asteroid discovered in 2016 by astronomers at Hawaii's Haleakala Observatory. It likely spans somewhere between 130 and 330 feet (40 to 100 meters) across and is a "quasi-satellite" of our planet, meaning it's orbiting the sun right alongside Earth in a temporary partnership. (Kamo'oalewa means "oscillating celestial fragment" in Hawaiian.)

Tianwen-2 is predicted to have arrived at Kamo'oalewa on June 7 and inserted itself into an orbit alongside the asteroid, according to an unverified timeline shared by freelance journalist Andrew Jones, a leading expert on China's space program. Around a month later, on July 4, the probe is expected to descend upon the space rock to collect samples from its surface, potentially employing a never-before-seen drilling technique to do so. (The CNSA has not released an official timeline for the mission or shared any recent updates about its progress.)

If successful, the samples are expected to be returned to Earth on Nov. 29, 2027, according to the same timeline. At this point, Tianwen-2 will then slingshot around our planet and head farther out into the solar system for its secondary mission: to rendezvous with and study 311P/PanSTARRS — a peculiar object beyond Mars, which displays characteristics of both comets and asteroids — in 2035.

Samples from Kamo'oalewa could help answer many interesting questions, including the true origin of the object, which some experts believe may have broken off from the moon.

"What makes [this mission] extraordinary is that we don't yet know [the object's] composition or origin," Li Chunlai, a researcher with the Chinese Academy of Sciences' National Astronomical Observatories and chief commander of Tianwen-2's ground application system, said in a state-sanctioned video translated to English. "We'll only obtain definitive answers after completing our exploration."

What is Kamo'oalewa?

There are currently eight known quasi-moons orbiting the sun alongside Earth, following the most recent quasi-moon discovery in September 2025. Unlike the similarly named "minimoons," which are asteroids that are briefly captured by Earth's gravity for a few months or years at a time, quasi-moons are temporary satellites that slowly circle our planet but are never gravitationally bound to it.

This relationship can last decades, or even centuries. For example, experts think Kamo'oalewa has been accompanying our planet for at least 100 years and could remain alongside it for another 300 years before it starts to fall out of sync with our solar orbit.

"The way Kamo'oalewa moves with Earth is kind of like a dog that might tag along with you for a while on a long walk through the woods, but it's not your dog," Richard Binzel, a planetary scientist and asteroid expert at MIT, told Live Science in an email.

The Ferris-wheel-size space rock is one of the closest quasi-moons to us, with a minimum distance of around 2.9 million miles (4.6 million kilometers) from Earth, or around 12 times farther away than our actual moon. It is also one of the fastest-spinning quasi-moons, rotating around its axis every 30 minutes. But unlike other quasi-moons, which likely originate from the solar system's main asteroid belt, between Mars and Jupiter, our current best guess is that Kamo'oalewa is actually a piece of the moon.

This hypothesis is based on observations from 2021 that showed Kamo'oalewa absorbs and reflects light similarly to the moon, hinting that the space rock may be a chunk of lunar material ejected by a long-ago meteor strike. More recently, in 2024, researchers narrowed down the most likely impact crater from which the asteroid originated: the 13.6-mile-wide (22 km) Giordano Bruno crater, located on the far side of the moon. However, there is still a chance that Kamo'oalewa is a main-belt asteroid that just happens to look an awful lot like lunar material.

"I am curious to find out the answer about its origin, since the debate on its [potential] lunar origin is still very open," Marco Fenucci, a mathematician at the European Space Agency's Near-Earth Objects Coordination Centre who has co-authored multiple studies on Kamo'oalewa, told Live Science. This mission should "definitely give us an answer to this matter," he added.

Scientists are also unsure whether Kamo'oalewa is a "solid monolithic rock," like the $100,000 quadrillion asteroid Psyche (the target of NASA's ongoing Psyche mission), or a "rubble-pile-like asteroid," such as Bennu or Ryugu, both of which have been explored by sample-return missions in recent years, Fenucci said.

Scooping up samples

Having arrived at Kamo'oalewa, Tianwen-2 will spend the next few weeks mapping the asteroid's surface at altitudes between 1,000 feet and 12.5 miles (300 m to 20 km) above its surface, according to limited mission details revealed by Chinese scientists in a January study. The resulting map will allow researchers to estimate the asteroid's density and work out the best landing spot.

On July 4, the probe is expected to swoop down and scoop up around 3.5 ounces (100 grams) of surface material, or regolith, from the asteroid, which is slightly less than what NASA's OSIRIS-REx mission managed to grab from Bennu. However, there are multiple ways this sampling process could play out.

If the asteroid is a pile of rubble, the probe will utilize a touch-and-go approach, which involves hovering just above the surface and using a robotic arm to reach out and grab the sample. This method was also used by OSIRIS-REx for Bennu and by Japan's Hayabusa2 mission, which scooped up samples from Ryugu.

But if Kamo'oalewa has a more solid surface, Tianwen-2 will attempt to land directly on the space rock and anchor itself in place before drilling into the asteroid. This has never been attempted before and could allow for longer contact time and "more controlled sampling," according to The Planetary Society.

After collecting samples, the probe will remain alongside the asteroid and conduct further analysis of its size, shape and trajectory.

In late April 2027, Tianwen-2 will depart Kamo'oalewa and begin the six-month journey back to Earth, where it will dump its samples in a return capsule that will fall to our planet's surface as the probe begins its long journey to rendezvous with 311P/PanSTARRS.

The return capsule will reenter Earth's atmosphere at around 27,000 mph (43,500 km/h), researchers wrote in the January study. That's slightly faster than the Orion capsule carrying the Artemis II astronauts traveled as it fell back to Earth in April.

What could we learn from Tianwen-2?

In addition to ending the debate over Kamo'oalewa's origin, samples from Tianwen-2 could reveal more about the solar system and our place within it.

For example, previously returned asteroid samples have helped to "tell us where Earth's water came from, how complex organic molecules were distributed in the early solar system, and how surface processes like space weathering alter asteroid properties over time," Fenucci said. These samples can also be used to "establish a link to known meteorites found on Earth" and help us learn more about these space rocks, he added.

The proximity of quasi-moons and minimoons to Earth also makes them valuable assets for future space exploration missions. Some researchers have proposed using them as temporary bases or refueling stations that could serve as stops on the way to Mars or other faraway destinations. These objects "could become literal stepping stones for human missions to practice what it is like to leave the Earth-moon cradle," Binzel said.

One particular idea that scientists want to explore is whether water can be extracted from these objects. And if Kamo'oalewa is a piece of the moon, that could have implications for NASA's planned moon base. "Someday, it might be possible to extract that water to provide resources for thirsty astronauts or even generate usable rocket fuel from the hydrogen," Binzel said.

Some near-Earth objects also pose a potential risk to our planet. And while Kamo'oalewa will likely never hit us (and would probably only cause localized damage if it did), there are much larger nearby space rocks that could trigger global catastrophes if they were to impact our planet.

"Over the time scale of centuries, these kinds of objects have a chance of striking the Earth," said Binzel, who invented the Torino scale used to measure the impact potential of near-Earth objects. Therefore, a better understanding of space rocks like Kamo'oalewa "can prepare us in how to deal with a threatening object if one were ever discovered," he added.

Finally, this mission will likely provide another opportunity to assess China's space exploration capabilities, which could hint at whether the country could overtake the U.S. as the top nation in space, as some experts predict.

A giant blob of abnormally cold water in the North Atlantic Ocean is shifting the Indian summer monsoon, threatening the livelihoods of more than 1 billion people, new research suggests.

The link between these two systems highlights a previously unrecognized connection that could inform weather forecasts in South Asia and shed light on climatic events elsewhere, scientists say.

The Indian summer monsoon is a rainfall pattern that lasts from June to September and is driven by temperature differences between the warm northern Indian Ocean and cooler seawater below the equator. Historically, the monsoon triggered heavy rainfall along the west coast of India and a huge region of northern India called the Indo-Gangetic Plain. But since 1999, this pattern has changed dramatically, the researchers reported in a new study.

Northwest India now receives about 25% more rain during the monsoon season than it did before 1999, while the Indo-Gangetic Plain gets roughly 4% less, the team found. This is disastrous for farmers, in particular, because their soils and crops are adapted to the old rainfall pattern, said study first author Mahendra Nimmakanti, a climate scientist at the Indian Institute of Science's Centre for Atmospheric and Oceanic Sciences.

"India is largely dependent on agriculture," Nimmakanti told Live Science in a joint interview with study co-author Matthew Huber, a professor in the Department of Earth, Atmospheric, and Planetary Sciences at Purdue University in Indiana. Higher-than-normal precipitation in northwest India is causing flash floods and crop losses, because agriculture in this region is adapted to dry conditions. Meanwhile, the Indo-Gangetic Plain has seen periods of drought that also caused crop declines and impacted farmers' livelihoods, Nimmakanti said.

Previous studies have linked shifts in the Indian summer monsoon to changes in the Atlantic Meridional Overturning Circulation (AMOC), a giant web of ocean currents in the Atlantic that regulates the global climate and carries heat to the Northern Hemisphere. Data suggests the AMOC is slowing due to climate change and releasing less heat in the North Atlantic Ocean than it did before. This may be causing a southward shift of the Intertropical Convergence Zone, a band of low-pressure atmospheric conditions around the equator that drives tropical monsoons, including the Indian summer monsoon.

But these studies didn't specify how the Indian monsoon might shift or explain the underlying mechanism in detail, Nimmakanti said. "They generally explain that if there is a weakening of AMOC, that suppresses the Indian summer monsoon," he said.

One part of the problem is that current climate models do not show the changes in the Indian monsoon that have happened in real life, possibly because they also don't fully capture shifts in North Atlantic sea surface temperatures. This is especially true for a region southeast of Greenland known as the "cold blob," where the water was colder between 1901 and 2021 than it was in the late 1800s, even as the ocean around it heated up.

The cold blob suggests the AMOC is weakening because it points to a reduction in the amount of heat reaching the North Atlantic.

To pinpoint how and why the Indian monsoon has changed, the researchers fed precipitation data, sea surface temperature records and other real-life observations into dozens of climate models. This reproduced the shifts observed over the past 27 years. However, the results only implied a correlation between shifts in the North Atlantic and changes in the monsoon, not that the former directly caused the latter.

To figure out if North Atlantic sea surface temperatures caused the Indian monsoon to behave strangely, the team added and removed the cold blob in a simulation. The results showed that the cold blob has shifted the Indian monsoon by creating a strong temperature gradient over the North Atlantic, which, in turn, affects jet stream winds and pressure systems in the atmosphere above Eurasia.

Specifically, the jet stream above the North Atlantic has intensified, and a "blocking" system over the Ural Mountains in western Russia has strengthened, Huber said. As a result, weather systems in India have changed, sucking moist air toward the country's northwest and away from other regions.

"It's a shifting of the high- and low-pressure systems," Huber said. "Realizing that these two systems were directly linked through this wave train coming off the North Atlantic, that was novel."

More than 1 billion people in India and other parts of South Asia depend on the monsoon for food security and economic stability. The new results, published April 27 in the journal AGU Advances, could help forecasters predict extreme rainfall and drought events in India and neighboring countries like Pakistan during the monsoon season.

Some researchers think the Indian monsoon is a key tipping point within the global climate, and the findings suggest the system crossed a threshold in 1999. Since then, the cold blob has caused a "persistent jet stream reorganization," leading to abrupt shifts in the monsoon, according to the study.

It's unclear how the Indian monsoon will evolve under intensifying climate change, because climate models produce different predictions of what will happen in the North Atlantic, and other drivers may come into play as the world changes, Huber said.

"What we do now know is that this is one of the key building blocks of formulating a theory for what will happen in the future," he said.

Corvids, including ravens and crows, have earned a reputation for being some of the smartest birds on Earth. They can recognize human faces, use tools, solve multistep puzzles and even hold funerals.

In recent years, scientists have added another surprising skill to the list: a grasp of numbers. Research suggests that corvids can distinguish between different quantities and, in some cases, even perform statistical analysis.

These discoveries have raised a provocative question: How deep do the roots of mathematical thinking go? While modern humans are the only known species to develop formal mathematics, studies of crows, monkeys and other animals suggest that the cognitive building blocks of math may have evolved hundreds of millions of years before people began doing calculations.

Few researchers have done more to uncover these abilities than Andreas Nieder, a professor of animal physiology and the director of the Institute of Neurobiology at the University of Tübingen in Germany. By examining the neural activity of both monkeys and crows, Nieder has found evidence that very different animal brains can process numerical information in surprisingly similar ways. Live Science spoke with Nieder about how these findings may reveal that the origins of mathematics are far older than our species.

Kenna Hughes-Castleberry: How did you get into researching crows and primates?

Andreas Nieder: After studying the auditory and visual systems for several years as a student, I realized that I wanted to focus on the neuronal foundations of intelligence and cognitive control functions. How does the brain give rise to abstract concepts, working memory, or the ability to follow complex rules deliberately? Of course, to study intelligence, you need intelligence specialists. I therefore began working with primates ‪—‬ more specifically, rhesus monkeys, arguably among the most intelligent mammals. They are closely related to humans, possess relatively similar brains, and share many cognitive abilities with us.

However, as a trained biologist, I was always interested in a broader evolutionary question: Are sophisticated cognitive abilities unique to mammals, or can they emerge in very different brains? Crows provided an ideal comparative species. Birds diverged from mammals more than 360 million years ago — roughly six times longer ago than the extinction of the dinosaurs. Yet despite this immense evolutionary distance, corvids display remarkably flexible behavior; in many ways, they are the feathered primates of the air.

KHC: Are crows difficult to study? Are they fun? Do they have personalities?

AN: Both primates and crows are demanding to study. Because they are highly intelligent, they require special housing and care. Since we investigate cognitive abilities under tightly controlled experimental conditions, they also require extensive behavioral training by skilled personnel. And, of course, the regulations governing research with these species are particularly strict.

At the same time, they are fascinating research subjects. Individual monkeys and crows differ noticeably in temperament and behavior. Some are curious and adventurous, others are cautious and reserved, and some learn new tasks much faster than others.

Their qualities can be quite striking. Some are reliable, highly motivated workers that perform consistently day after day. Others are sensitive divas who seem to require special treatment before they are willing to cooperate. Researchers generally avoid anthropomorphizing, but there is little doubt that individual animals exhibit stable behavioral traits that we would reasonably describe as distinct characters.

KHC: You've found that crows understand the concept of zero. How do we know this?

AN: We trained crows to recognize different numbers — sets containing one, two, three, four objects, and so forth. We then included trials in which no items appeared at all. The remarkable finding was that the birds treated an empty set as a quantity and as part of the numerical continuum. They behaved as though the empty set belonged before "one." Their error patterns were particularly revealing: They confused zero more often with one than with larger numbers, exactly as one would expect if zero were mentally represented as a numerical quantity next to one. In addition, recordings from neurons in the crow brain showed cells that responded selectively to empty sets. This suggests that zero is not merely a behavioral trick but is represented neurally as a meaningful numerical category.

KHC: To play devil's advocate, is the ability to recognize the difference between something and the lack of something really that surprising? Is it akin to the human concept of zero?

AN: That's an important question. Simply recognizing that nothing is present or absent is not surprising. Many animals can distinguish between the presence and absence of objects. The key issue is whether they treat "nothing" as a quantity that can be compared to other quantities.

Our experiments suggest that crows do more than detect absence. They position empty sets within an ordered numerical sequence, at the low end of the number line, and show distance effects similar to those observed with other numbers. For example, they find it easier to distinguish zero from two than zero from one.

That said, we should not claim that crows possess the full human mathematical concept of zero. Humans use symbolic zero in arithmetic, algebra, calculus and formal mathematics. What we have demonstrated is a foundational precursor: a nonsymbolic numerical representation of zero. This may represent an evolutionary building block from which more sophisticated human concepts eventually developed.

KHC: You've also found that crows can perform statistical analysis. Tell me more about these findings and what you showed.

AN: We trained carrion crows [Corvus corone] to associate a series of arbitrary visual signs, colored geometric images displayed on a touch screen, with different reward probabilities. One sign might yield a food reward 90% of the time, another 70%, another 50%, and so on down to 10%. Importantly, the signs themselves carried no inherent meaning; the birds had to learn these probabilities through experience.

Once the birds had learned these sign-probability associations, we presented them with pairs of signs and asked them to choose one. To maximize their rewards, they should select the sign associated with the higher reward probability. The crows did exactly that. Even when confronted with many novel pairings, they reliably chose the statistically more favorable option.

This does not mean that crows perform formal statistics in the human sense. They are not calculating percentages or solving probability equations. However, the results show that they can extract probabilistic regularities from experience, store this information in memory, and use it flexibly to make reward-maximizing decisions under uncertainty. These are fundamental ingredients of statistical reasoning and are highly valuable in natural environments, where animals constantly have to make decisions based on incomplete information.

KHC: Have researchers tried similar tests on babies or young humans, and if so, how do we stack up?

AN: Yes. Developmental psychologists have conducted many related studies with infants and young children. Even before learning language, infants show sensitivity to quantities, numerical differences and simple probabilistic information. By around 4 years of age, children also display an intuitive understanding of empty sets.

What is striking is that the behavioral signatures observed in crows resemble those seen in preverbal human infants and nonhuman primates. Of course, human children eventually develop symbolic mathematics through language, education and culture, which takes them far beyond the abilities observed in animals.

KHC: Can these findings tell us anything about how the human understanding of math evolved?

AN: They suggest that some foundations of mathematics may predate humans by a very long evolutionary timescale. Humans did not invent numerical intuition from scratch. Rather, we appear to have inherited ancient cognitive systems that allow brains to estimate quantities, compare numbers, and represent concepts such as zero approximately.

The fact that crows and primates — two distantly related groups — show similar numerical abilities suggests that these capacities may emerge whenever evolution favors flexible intelligence. Human mathematics likely built upon these ancient cognitive foundations and then expanded dramatically through language, symbols and culture.

KHC: What's something a general audience might be surprised to learn about crows?

Many people are surprised to learn that crows are songbirds. Most people associate songbirds with melodic singers such as nightingales or blackbirds, not with the harsh cawing of a crow. Yet crows do learn a significant part of their vocal repertoire and are even known as apt imitators, even of human speech sounds — the internet is full of funny videos in which crows imitate human speech.

What makes this particularly interesting is that their vocalizations are not merely reflexive calls. In our experiments, we found that crows can exert volitional control over their vocal behavior. They can learn to produce vocalizations in response to arbitrary cues and withhold them when required, demonstrating a level of cognitive control over vocal output that is considered an important prerequisite for complex communication and, ultimately, language.

More recently, we showed that crows can even use their vocalizations to count. In a recent study published in [the journal] Science, we trained crows to produce a specific number of calls — between one and four — in response to visual or auditory cues. Remarkably, they not only generated the correct number of vocalizations but also appeared to prepare the intended number before they started calling. This suggests that they can represent numerical information and use it to guide a self-generated sequence of vocal actions.

Taken together, these findings show that crow vocalizations are far more sophisticated than most people assume. Their characteristic "caw" is not just a simple call — it can be brought under deliberate cognitive control and even used to express numerical information. For a bird, that is a remarkably advanced ability.

This interview has been edited for length and clarity.

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In southwest China, Chinese soldiers load and fire rockets toward the sky as aircraft and drones circle overhead, dropping their toxic cargo into the air. The weapons are not trained on an enemy, and the planes aren't dropping bombs. Instead, they are targeting the clouds hovering in the sky.

This footage is just a tiny snapshot of the massive, countrywide effort to seed the clouds with rain at an unprecedented scale.

More than 50 countries around the world use cloud seeding to modify the weather at small scales, including the United States.

But China is the world leader, employing around 50,000 people; using thousands of rocket launchers and dozens of planes; and investing the equivalent of billions of dollars in these initiatives, experts told Live Science.

In 2018, China embarked on its most ambitious cloud seeding plan. The Tianhe ("Sky River") project aimed to create a permanent airborne water "corridor" from one river basin to another on the Tibetan Plateau. The project was intended to be part of the country's much bigger South-North Water Transfer project — a massive effort to transfer water to China's highly populated and water-scarce North and East.

From the start, the Sky River faced scathing criticism from scientists who said the project was unworkable. Yet China forged ahead.

China's pursuit of such a scientifically questionable geoengineering technology shows just how far Chinese authorities are prepared to go to achieve the country's water and climate goals. It also reveals how the Chinese government views the natural world, experts have said.

"There is an impetus to control and to view the environment as a machine or an infrastructure that can be controlled," Emily Yeh, a professor of geography at the University of Colorado Boulder, told Live Science.

The science of cloud seeding

China uses cloud seeding to produce precipitation to build up snowpack, help alleviate droughts, reduce the impact of hailstorms, and create skies clear of clouds and pollution for official events — as it did most famously during the 2008 Beijing Olympics, experts told Live science.

But cloud seeding can't create rain from an empty sky. Instead, it causes existing clouds to generate precipitation more efficiently by injecting particles into a cloud. Water droplets then coalesce around these particles, and the water eventually falls as rain or snow.

"Every single drop in any cloud you have ever seen — there's a particle in it," Rob Rauber, an atmospheric scientist at the University of Illinois Urbana-Champaign, told Live Science. Cloud seeding speeds up the raindrop-forming process by introducing more particles, he explained.

There are two main ways to do this, depending on whether the temperature of the clouds is above or below 32 degrees Fahrenheit (0 degrees Celsius). Warm-cloud seeding is known as hygroscopic seeding, while cold-cloud seeding is called glaciogenic seeding.

"They have the same general goals or approach," Jeff French, head of atmospheric science at the University of Wyoming, told Live Science. "And that is to introduce something into the cloud that would increase the efficiency in which cloud droplets or ice crystals are able to grow to precipitation-size particles and fall out of cloud either as rain or as snow."

A salt such as sodium chloride is typically used for hygroscopic seeding to attract water droplets, French said. Glaciogenic seeding, by contrast, takes advantage of cold clouds' supercooled water — water that is liquid even when temperatures are below freezing — by introducing silver iodide. This substance has a similar structure to ice and collides with supercooled water in a cloud, causing it to freeze and eventually fall from the cloud, French said.

Scientists insert seeding particles into clouds in a number of ways, including by dropping them from planes and drones, firing shells or rockets into the clouds from the ground, or burning materials in chambers that release the combustion byproducts into the air.

Scientists are still learning exactly when and how to use these techniques most effectively. Rauber and French both noted that it's difficult to quantify cloud seeding's impact.

"It becomes kind of a quagmire when you ask that question: 'Does cloud seeding work?'," French said. For his research, he used airplanes, ground sensors and radar across the U.S. Mountain West to measure the effects of seeding from aircraft on the initiation and growth of crystals and eventual snowfall. "From a physical standpoint, I can say very confidently that cloud seeding works," French said.

However, that experiment was in cold, mountainous conditions, and the impact of cloud seeding depends on many conditions, so tracking whether cloud seeding increases precipitation over a longer period and in different conditions can be challenging.

"Not all clouds are created equal," French said. Some are colder or warmer, and the seeding material won't work as well; in others, the size or distribution of droplets makes precipitation less likely. Even within a small region, the snowfall varies tremendously from one point to another. And beyond a small region, all bets are off.

"If you have a very successful cloud seeding program, that is producing, maybe 7% or 9% or even 10% more precipitation over a mountain range, downstream of that mountain range, the impact may be 1%," French said. "But it is a really difficult number to get our arms around."

French added that scientists should be careful to not overpromise what cloud seeding can accomplish.

"If the promise is that cloud seeding is going to eliminate droughts even on a local level, the answer is no, it can't live up to that. There's no scientific evidence," French said. But if targeted properly, it can moderately increase natural precipitation, he said.

Cloud seeding on the Tibetan Plateau

Despite cloud seeding's limitations, China has established weather modification bureaus across the country.

"They have a whole campus of people who are working in the weather modification field," Rauber said. "They have a fleet of aircraft — they're on a whole different scale than anything that goes on anywhere else in the world."

Chinese researchers claim that the country has made huge strides in its weather modification. Reports from state-owned media suggested that weather modification efforts increased precipitation by 168 billion tons between 2020 and 2025, and that in experiments, just one cup of cloud seeding material generated 30 Olympic-size pools' worth of precipitation over an area the size of Yellowstone National Park in the arid Xinjiang region.

These weather modifications have also been conducted on the Tibetan Plateau. The vitally important region, nicknamed Asia's Water Tower, is the source of multiple major rivers that supply water to nearly 2 billion people across Asia. But the plateau is facing increasing desertification and glacier loss due to human-caused climate change and other human activities such as overgrazing animals.

China's cloud-seeding ambitions for the plateau reached a whole new level in 2018, when authorities announced the Sky River project. The controversial project aimed to use cloud seeding to create precipitation across a 620,000-square-mile (1.6 million square kilometers) area in the Tibetan Plateau — about the size of Alaska — to divert Indian monsoon rains above the Yangtze River basin and channel the water to the Yellow River basin. From the Tibetan Plateau, the Yellow River flows north and east into the parched northern regions of China, while the Yangtze flows south and east into less-water-scarce areas. The initial plan claimed the project would transfer up to 7% of the country's total annual water consumption, reports noted.

The atmospheric channel was intended to be part of the country's colossal South-North Water Transfer Project, circumventing the region's challenging terrain by moving the water in the sky instead.

The plan, due to be completed in 2025, called for seeding this atmospheric river using tens of thousands of silver iodide-burning chambers on the ground, linked to a series of meteorological satellites that would analyze the weather conditions. Information from these satellites would automatically trigger the burners when the conditions were suitable for cloud seeding.

However, the plan was immediately met with a barrage of criticism from scientists in China. In a translated statement, Hancheng Lu, a professor at the National University of Defense Technology's School of Meteorology and Oceanography, called the project "an absurd and fantastical project with neither scientific basis nor technological feasibility."

The project was unworkable because it is not possible to convert all atmospheric moisture to rain, or to channel moisture in this way, Yeh said.

As of 2022, researchers were working on a significantly scaled-back version of the project. However, China's official channels have gone dark on the topic.

China's newly announced five-year plan, which sets out the policy direction of the country from 2026 to 2030, references weather modification enhancements but doesn't mention this specific project, according to reports from Chinese media.

This has led experts to speculate that the project was quietly canceled.

"When one goes to China and asks atmospheric scientists not involved in it about it, they just sort of laugh, and it's like this embarrassing incident," Yeh said. "It was never possible."

To see whether the project was still going forward, Live Science reached out to several researchers involved in the project, but they did not reply by the time of publication.

The fears of cloud seeding

The pursuit of the Sky River project — despite the low likelihood that it would ever work —— has caused significant alarm in neighboring countries. India relies on the monsoon rains and rivers such as the Brahmaputra, which starts in the Tibetan Plateau before flowing through India and Bangladesh on a 1,800-mile-long (2,900 km) route to the sea. There are also suspicions about cloud seeding being used to cause flooding across borders.

Many of these fears are overblown, experts told Live Science. Rauber noted that cloud seeding can't influence weather enough to reduce water in a wider weather system.

"This is always a question of, 'Are you robbing Peter to pay Paul?'" Rauber said. But the amount of water in storm clouds "is way greater than anything cloud seeding is going to extract."

Climate geoengineering

China's all-in pursuit of technologies like cloud seeding — even on the internationally important and politically sensitive Tibetan Plateau — has raised concerns that China is prepared to go to extreme lengths to engineer its way out of its problems — even when it involves scientifically dubious geoengineering projects with massive risks.

China's determination to address climate change and investment in megaprojects that attempt to engineer the natural world, such as the upcoming Motuo megadam in Tibet and colossal tree-planting projects in northern China, are also signs that China is moving toward larger climate geoengineering, experts have suggested.

This may even involve attempts to change how much sunlight reaches the planet's surface, experts have speculated.

"Given similarities, weather modification could serve as a means to incrementally build legitimacy for solar radiation management, in China and beyond, which may ultimately make it possible to deploy it," researchers argued in a 2019 study.

However, there's no evidence that China is currently pursuing such climate modifications, and it's unlikely they'd do so without some cooperation or buy-in from other countries, researchers wrote in 2023.

"It is currently unlikely that China would deploy SRM unilaterally. But its weather modification programme does demonstrate the country's willingness and capability to undertake large-scale atmospheric intervention projects," the study authors wrote.

Solar radiation modification aims to release particles such as sulfur high into the atmosphere to reflect sunlight back into space in an effort to limit global heating. It is being increasingly investigated by researchers and governments. The controversial concept has never been demonstrated on a large scale, and studies suggest it has many potential risks, such as the potential to shut down monsoon rains.

Scientists have already seen some of the negative impacts of natural solar radiation modification, for instance in the aftermath of large volcanic eruptions, such as Tambora in 1815. "It led to the suppression of the monsoon, because the monsoon is driven by heating from the sun, Rauber said. "And that cuts back on rain in tropical areas, and that causes droughts, which causes all sorts of diseases and can lead to mass starvation," he added.

"The evidence from nature is don't mess with Mother Nature," he said.

The patient: A 28-year-old woman in New Hampshire

The symptoms: In March 2020, the woman developed a high fever, chest tightness, shortness of breath and diarrhea, and she lost her sense of smell and taste. She also experienced coughing fits so intense that they caused her to faint. Based on these symptoms, her primary care provider diagnosed her with COVID-19, although she was not formally tested for the illness due to the lack of diagnostic testing available at the time.

After her diagnosis, she did not seek further medical care due to concerns about out-of-pocket costs, according to a report of the case.

What happened next: Three weeks after her symptoms started, the patient felt well enough to work from home. However, four weeks after that, many of her symptoms returned. She also noticed new feelings of disorientation and felt that "something was off with faces." Her primary care doctor suggested she go to an emergency room, where a CT scan was taken of her brain. The scan didn't show any active bleeding, the report notes, and she was discharged.

In June 2020, the patient spent time with family for the first time since catching COVID-19 and found she could not recognize her father or visually distinguish him from her uncle. She still recognized people by their voices, though.

The patient worked part time as a portrait artist; she used to be able to check her reference photos every 15 to 30 minutes but found she now struggled to hold the details in her mind. She told doctors that "faces are like water in my head," according to the case report.

The patient also had trouble doing everyday tasks, such as navigating her local grocery store or finding her way back to her car in a parking lot. In November 2020, she also started having balance issues and frequent migraines.

The diagnosis: Based on her wide-ranging and relapsing symptoms and her suspected history of COVID-19, doctors diagnosed the patient with post-acute sequelae of COVID-19 (PASC), now known as long COVID. They diagnosed her difficulties with recognizing faces as "face blindness," or prosopagnosia.

Roughly 2.5% of the general population is thought to be born with some degree of face blindness, while others can acquire the condition later in life. The exact number of people with acquired prosopagnosia is unclear, but some estimates suggest roughly 1 in 30,000 people in the U.S. are affected.

Many people with acquired prosopagnosia also have issues navigating familiar spaces. That was also the case with this patient, likely due to the "proximity of brain regions critical for scene and face processing," the case report authors noted.

To assess the extent of the patient's prosopagnosia, doctors had her complete several tests of facial memory, which asked her either to memorize strangers' faces or recognize celebrities' faces. The patient performed markedly worse on these tests than 10 women of similar age who were used as a comparison group.

However, she performed as well as the comparison group on other types of cognitive tests, suggesting her deficits were fairly specific to faces. She also got normal scores on tests of facial perception — the ability to recognize that a face is a face — so her face blindness seemed tied more to memory deficits for faces, the report authors said.

The treatment: The case report does not detail a specific course of treatment, and in general, few treatments exist for face blindness. If there's a clear cause for the deficit — such as a tumor in a key part of the brain for facial processing — addressing that underlying issue can help reverse acquired face blindness.

If the condition ends up being permanent, there are various strategies that can help patients cope. For instance, "perceptual training" can improve patients' ability to identify and remember the features of a person's face. Additional strategies include training people to use other cues, like voices and social context, to identify people.

What makes the case unique: In this patient's case, the report authors suspect that her COVID-19 infection triggered her face blindness either acutely or in the aftermath of the infection.

Various infections have been tied to face blindness; both bacterial meningitis and Whipple disease (caused by the bacterium Tropheryma whipplei) have been flagged as culprits, although such cases are uncommon. In a second known case involving COVID-19, a different person developed face blindness after an infection but had also had a stroke in the right hemisphere of their brain, a known cause of prosopagnosia.

The 28-year-old woman, by contrast, wasn't thought to have suffered a stroke, and it's unclear exactly how COVID-19 led to her facial processing issues.

The case report authors surveyed more than 50 other people with long COVID, to see if they also had signs of face blindness. While many showed general declines in visual recognition and navigational abilities, the group didn't have a specific problem with faces. So while long COVID is known to cause a range of neurological issues, it appears that face blindness is a rare consequence.

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!

Archaeologists in Germany have unearthed an unusual burial of an injured man who was thrown into an abandoned kiln nearly 5,000 years ago. Because archaeologists don't typically find artifacts or bones in kiln pits, they suspect the man may have been a human sacrifice.

While workers were constructing a power line near Gerstewitz, a village in central Germany, archaeologists found a Corded Ware culture grave, according to a June 15 statement from the State Office for Heritage Management and Archaeology (LDA) Saxony-Anhalt.

The Corded Ware culture, named after the distinctive cord-like impressions found in their pottery, spread across Northern Europe between the Late Neolithic and the Bronze Age, around 2900 to 2050 B.C. Graves of Corded Ware people tend to follow a strict pattern: Men were buried on their right side, women were interred on their left, and everyone was buried in a crouched position facing south. But sometimes, graves deviate from this pattern.

The newly excavated grave at Gerstewitz revealed the skeleton of a man who was about 25 years old when he died. He was buried in a crouched position facing south, but rather than being placed in a grave or under a small mound, he was found in a kiln pit. This pit, essentially a hole that had been dug into the ground, held ancient evidence that people had used it to burn material, such as wood or food, or to fire clay. Additionally, the man's skull showed signs of injury.

Experts have suggested three possible explanations for the unusual burial. The skull injury may have resulted from violence, meaning someone murdered the man. Alternatively, he could have perished in a Copper Age battle lost to history. But a third possibility is that he was placed in a kiln pit as a human sacrifice.

Oliver Dietrich, an archaeologist at LDA Saxony-Anhalt, wrote in the statement that, in rare cases, Corded Ware kiln pits contain cow or dog bones thought to be sacrificial offerings to unknown deities. While it's possible this man was a human sacrifice, Dietrich noted that future laboratory analysis should provide more information about the grave and the person buried there.

This is not the first time a sacrificial pit has been found in Gerstewitz. Last year, archaeologists with LDA Saxony-Anhalt discovered 12 pits ringed by a moat-like ditch. The pits were full of dog bones, human skulls and complete ceramic pots and had been sealed with the rubble of burnt houses, according to a 2025 statement about that discovery. An additional human skeleton was found buried in a converted oven pit. These finds, however, were attributed to the Salzmünde Culture (3400 to 3050 B.C.), which predated the Corded Ware people.

Other discoveries near Gerstewitz have revealed that the area was settled and occupied for over 6,000 years. The excavation there will last until at least 2027, when the power line project is expected to be completed.

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

Today (June 17), for the first time in 11 years, people across North America will be able to look up in the daytime sky and see Venus temporarily vanish behind the faint crescent moon.

The rare skywatching spectacle can be viewed with the naked eye and recorded without any special equipment, as long as the weather cooperates — however, using a good pair of binoculars or a backyard telescope will make it much easier to see the faint light of Venus in the daytime sky. No matter how you go about skywatching, you must take great care not to stare directly at the sun while doing so.

During the event, known as a lunar occultation, the moon will briefly pass between Earth and Venus, which has been shining especially bright over the past few weeks while hanging out alongside Jupiter in the evening sky. As a result of the occultation, the hellish planet will appear to blink out of existence, before reappearing around an hour later, allowing for two separate skywatching experiences. The last time this happened was on Dec. 7, 2015, and you will not be able to see it again until 2029.

How to see Venus disappear

The occultation will be visible from the 48 contiguous U.S. states, as well as from large parts of Canada and some countries in the northern half of South America — assuming there are clear skies at the time of the event. (The latest forecast suggests that weather conditions will be most favorable along the West Coast.)

As with most skywatching events, such as solar eclipses, not everyone will see it at the same time. For example, people in San Francisco will observe Venus vanish at around 11:34 a.m. PDT, while those in Miami will watch the planet disappear at about 4:06 p.m. EDT (around 92 minutes later when disregarding time zones).

The duration of the occultation will also vary with location. For example, Venus will reappear after around 58 minutes for viewers in San Antonio, but people in Philadelphia will have to wait roughly 80 minutes to see the planet again.

You can see the exact timings for more than 700 locations across the U.S. in a list compiled by the International Occultation Timing Association.

The best place to watch both the disappearance and reappearance of Venus will be from within the shadow of a large tree or building. Blocking out the sun will not only make it easier to see both the moon and Venus but also reduce the risk of sustaining eye damage by looking directly at the sun.

If you are struggling to see the occultation, try using your phone camera to zoom in on the waxing crescent to better locate and record Venus, Spaceweather.com recommends.

What the June 17 lunar occultation will look like

During the event, around 11% of the moon will be faintly visible in the daytime sky, according to Sky & Telescope. Around three-quarters of Venus will be visible — although it will look like a single spot to the naked eye — so the planet will shine much brighter than the moon. The pair will be collectively located around 38 degrees from the sun in the sky.

Venus will vanish behind the side of the moon opposite the illuminated crescent and will take around 30 seconds to disappear completely. It will then reappear above the crescent, similar to the iconic "Earthrise" photos taken by lunar astronauts, such as the Artemis II crew. (The exact spot where Venus disappears and reappears will depend on where you are in the world.)

If you miss this occultation or fancy another skywatching spectacle, be sure to head back outside later the same day, around an hour after sunset, when Venus, Jupiter and Mercury will shine alongside the crescent moon as it passes in front of the Beehive Cluster (also called M44).

A colossal chunk of sea ice roughly the size of Texas is missing from the west coast of Antarctica, and scientists fear it might never form again.

Antarctica is currently in winter, which runs from March to October on the southernmost continent. During the winter months, floating sea ice surrounding the continent typically grows, driving currents that regulate Earth's climate. But this year, there's a notable ice gap over the Bellingshausen Sea, on the western side of the Antarctic Peninsula.

Satellite observations have revealed that around 250,000 square miles (650,000 square kilometers) of sea ice hasn't formed yet, compared with the average amount of sea ice between 1991 and 2020, The Guardian reported last week. For comparison, the ice gap covers an area slightly larger than France or nearly the size of Texas.

Will Hobbs, a sea ice-ocean interaction scientist at the University of Tasmania, told The Guardian that he was "concerned" by the lack of sea ice and that it was "depressing." Hobbs noted that this year represents the third time in four years that the region's sea has been very low.

"I don't think we will see sea ice there any more," he said. "It's done."

Researchers still have a lot to learn about sea ice changes in Antarctica. Hobbs said that the sea ice loss was likely linked to changes in the ocean and that scientists are trying to determine whether global warming was a factor.

Sea ice has declined much more slowly in Antarctica than in the Arctic. But in recent years, scientists have been witnessing an astonishing change in the sea ice extent. One record low in 2016 was followed by another in 2022 and then a third in 2023.

Edward Doddridge, a physical oceanographer at the Institute for Marine and Antarctic Studies in Australia, told ABC News (Australia) that he was no longer surprised by sea ice loss.

"It's not good news, but it has become a pattern that we're expecting now," Doddridge said. "A warming world is going to have less sea ice."

The diminished winter sea ice is likely to have a variety of knock-on effects. For example, this area of sea ice normally provides important habitat for animals like krill and penguins. Sea ice also plays an important role in regulating the climate, including by driving key ocean currents, insulating the ocean from the sun, and protecting ice shelves at the mouths of glaciers.

Down the coast from the missing sea ice, researchers have warned that a key ice shelf is about to disintegrate from Antarctica's Thwaites Glacier — nicknamed the "Doomsday Glacier" because its collapse could raise sea levels by 2.1 feet (65 centimeters) in the coming centuries, flooding coastal communities worldwide. The ice shelf helps protect the mouth of the glacier by acting as a buttress, thereby restraining the flow of ice from the glacier into the sea.

Thwaites Glacier has been melting rapidly since the 1980s, which is part of a wider concern for the West Antarctic Ice Sheet that it helps to support. The collapse of such an ice sheet is considered one of the major environmental tipping points, or "points of no return," that humanity must avoid in the fight to rein in climate change.

The wreck of a Japanese prison ship that was sunk by U.S. warplanes and went down with more than 1,000 Allied prisoners of war in 1944 has been discovered in the Philippines.

The vessel was one of the notorious "hellships" used by the Japanese to ferry POWs between work camps. Many of the prisoners who died when the ship sank had worked on the infamous Burma-Thailand "Death Railway."

"Sadly, a lot of these prisoner transport ships were sunk by the Allies," expedition leader and American TV show host Josh Gates told Live Science. "The ships were painted to just look like military vessels, and they were inside the Japanese convoys — so the Allies thought they were legitimate military targets."

Gates teamed up with the Hellships Memorial Foundation, a U.S.-registered non-profit based in Subic Bay in the Philippines, to investigate the sinking of the hellship Hōfuku Maru. Its wreck had never been found, probably because searchers were guided by incorrect U.S. records to look too far north, he said.

But Japanese wartime records were more precise about the wreck's location, helping the team find the remains of the Hōfuku Maru in January, Gates said. His team has since made five dives to the wreck, which sits a few miles off the west coast of the main Philippines island of Luzon at a depth of about 160 feet (50 meters).

Prison ships

Japan used more than 130 hellships during World War II, but the wrecks of only a few have been found. Many hellships, including the Hōfuku Maru, were converted freighters. The Hōfuku Maru was used as a prison ship from 1942 until its sinking about two years later.

Gates said the vessel was part of a Japanese military convoy sailing from the Philippines to Japan when it was attacked on Sept. 21, 1944. U.S. warplanes had spotted the convoy, and one dropped a torpedo that cut the Hōfuku Maru in half. It quickly sank.

But the ship had roughly 1,200 Allied POWs on board, from the British and Dutch armies, many of whom had been forced to work on the Death Railway. Some were able to swim ashore, but they were recaptured by the Japanese. About 1,040 died in the sinking, Gates said.

War captives

The 1929 Geneva Convention placed strict limits on the use of prisoners of war for labor, but Japan was infamous for flouting these rules during World War II, claiming that it never ratified the convention and that wartime made POW labor important. Japan used POWs for slave labor on railways and docks, as well as in factories and mines. Of the roughly 132,100 prisoners captured from the United States and United Kingdom armies, nearly a third of them — about 35,000 people — died of exhaustion, malnutrition and disease.

Gates said the Japanese hellships used to ferry thousands of POWs between work camps were miserable places themselves: there was little light, air or food, and prisoners might be kept there for months. Human remains have been identified on the newfound wreck, and it will now be considered a war grave, he said. International conventions aim to prevent such wrecks from being disturbed.

The team first spotted the wreck with sonar, and then dove to identify parts of the structure that confirmed it as the Hōfuku Maru. They also mapped the wreck with a remotely operated underwater vehicle, which helped them determine that the ship had split into separate parts, just as accounts of the sinking had reported.

The Hellships Memorial Foundation would now work to try to locate the families of the victims, Gates said.

At age 19, John McFall thought he might never walk again after his right leg was amputated above the knee following a motorcycle accident. Fast-forward more than two decades, and he is now on the verge of becoming the first physically disabled person in space.

McFall, 45, is a British surgeon and former Paralympic athlete who won multiple medals as a T42-class sprinter. In 2022, he joined the European Space Agency's (ESA) Fly! program, which aimed to see if a person with a physical disability could live and work in low Earth orbit. And in February 2025, he became the first member of the program to be cleared for a potential future mission to space.

More recently, on June 2, the U.K. government announced that McFall had been selected as a prospective member of the first crew to live on Haven-1, an upcoming commercial space station from U.S. company Vast that is scheduled to be the first of its kind in low Earth orbit, if it launches on time early next year.

If everything goes according to plan, the roughly 30-day mission will help answer a series of interesting questions about how living in space might be both challenging and advantageous for people with physical disabilities.

Live Science spoke with McFall about what it would mean to break new ground, wearing a prosthesis in space and how microgravity might uniquely affect him.

Harry Baker: How did it feel to get the news that you might be going to space next year?

John McFall: Awesome. Very awesome, very exciting. And it feels like we're one step closer to realizing this amazing opportunity and achieving this very exciting milestone in human space exploration.

HB: What would it mean to you personally to become the first physically disabled astronaut in space?

JM: To me personally, it doesn't make a difference. In terms of "what an achievement for me," I don't tend to think of it like that. However, I am very aware that the broader message that it sends to wider society about what people are capable of — whether they have a disability or not — is very interesting and powerful. So I'm proud to be a very small part of that movement, if you like, and the journey of making society a more tolerant and inclusive place.

HB: What advantages do you think your disability might give you in space compared with other astronauts?

JM: It's a good question because we don't actually know. We can hypothesize, but until we actually get into space and conduct some science that's specifically relevant to my disability, we won't know. But there are some theoretical benefits.

One is that when you live in microgravity, you get a shift of fluid from the lower part of your body up into the upper part of your body and your cranium. This can cause swelling of the optic disk, which can temporarily affect vision. It's called spaceflight-associated neuro-ocular syndrome (SANS), and it affects around 70-75% of astronauts. I would hypothesize that, having a reduced lower limb volume to start with, you're going to get a proportionally smaller fluid shift in microgravity, relative to your physiological capacity to process it, reducing the risk of things like SANS.

Another is that in microgravity, because you're weightless, you're not using your bones as much, and your body naturally resorbs them. So your bones get weaker and thinner. And one of the byproducts of this is that you have to excrete a lot of calcium, and you do this via peeing it out. As it [calcium] passes through your renal system, or kidneys, this causes an increased risk of kidney stones in microgravity. So again, having lower bone mass to start with — but retaining the same physiological capacity to metabolically process calcium — there is potentially a lower risk of kidney stones.

So those are two small-but-hypothetical benefits of my particular disability in space. But the real answer is, we don't know until we do the science (i.e., urine samples, blood samples and eye examinations in orbit).

HB: How might space be more challenging for you than for other astronauts?

JM: Again, we don't know. The question is, do you really need both your lower limbs to help you stabilize and support yourself whilst your hands are doing tasks? And is having two legs useful in what we would call normal intravehicular operations [conducted inside the spacecraft], whether it be cargo operations, maintenance, this sort of stuff?

When we went through the feasibility initiative, trying to think of and work out all these scenarios, we couldn't really think of a disadvantage other than maybe having to work slightly harder.

HB: Will you be wearing a prosthesis in space?

JM: The plan is to wear a prosthesis. We deemed quite early on that wearing a prosthesis in a spacecraft would be a necessity, mainly at launch time. If there was an emergency that required me to get out of the spacecraft and get off the crew access arm and away from the launch site, it would be ideal wearing a prosthesis to do that.

But in space, we don't know whether it's going to be an advantage or be required for these intravehicular activities. Where I would definitely need to use one is on a long-duration mission where I need to exercise lots. I use a prosthesis to exercise on Earth, and I would use a prosthesis to exercise in orbit. However, short-duration missions [like this one] do not.

The prosthetics I use are modular, so I wear a socket — that's what's left of my leg goes inside — and then the hardware, what we call the terminal device, is attached to the socket. What I would envisage doing is always wearing the socket, because that way, you maintain consistency. But [for] the terminal device itself, I have a quick-change adapter that you can just unplug the device, and you can take it off and, likewise, put it back in again.

It's "plug and play," if you like, and [it will allow me to] make assessments of whether it's useful or not.

HB: Will your prosthesis need to be specially made for the trip?

JM: Not really. We are certifying a number of prosthetic hardware items to fly, but they're all what we call "commercial, off-the-shelf items." So they're products that are widely available.

However, there are some very small changes that we need to make to make them compliant with the safety requirements of the space station environment and the spacecraft, such as fireproof tape around certain parts of the device or changing the hydraulic fluid so it's less toxic in case there is a leak.

We're also doing a small amount of redesigning to the shape of the foot to make it more ergonomic to interface with things like rails and straps inside the space station, because you often slip your foot under rails and straps.

HB: Could anything you learn from your mission help physically disabled people back on Earth?

JM: Yeah, I think so, certainly from a prosthetics point of view. There are prosthetic developments that we have made that will benefit other prosthetic users in the future.

I mentioned this quick-change adapter. We have revised or reengineered this particular device to perform in a certain way, which I think will have advantages for a whole range of lower-limb amputees. The socket technology ‪—‬ the interface between my stump and the prosthesis ‪—‬ is [also] going to be redesigned and potentially has very beneficial applications for lower-limb amputees again.

HB: Are you hoping to be selected for more missions in the future? And would you like to become the first physically disabled person on the International Space Station (ISS) or the moon?

JM: Yeah, absolutely. I hope that we use this opportunity to demonstrate that it is very feasible, and I hope that that would put me in line for selection of missions in the future.

I would love to, in the future, potentially spend longer in space, demonstrating that it's possible for someone with a disability to live and work in space and cope with everything that comes with that.

And absolutely, I would love to go to the moon. You know, someone with a lower-limb disability, when you propose that against walking on the moon, it's quite a powerful statement, and I would love to do that.

Editor's note: This interview has been condensed and edited for clarity.

For decades, physicists have pursued a goal that sounds nearly impossible: to build a clock that keeps time using an atom's nucleus rather than the electrons orbiting it.

Now, researchers have demonstrated the first functioning nuclear clock ‪—‬ an advancement that could eventually lead to more robust timekeeping devices and new ways to search for dark matter and physics beyond the Standard Model.

"Having worked in this field for more than 15 years, it is just beautiful, how a very 'wild' idea such as manipulating an atomic nucleus with a laser has turned into reality," Thorsten Schumm, a professor of quantum metrology at the Vienna University of Technology and a member of the research team, told Live Science via email.

How is a nuclear clock different from an atomic clock?

Today's most accurate clocks are optical atomic clocks, which measure the frequency of electrons jumping between different energy levels inside atoms. These clocks are so precise that they would lose less than a second over a 100 million years.

A nuclear clock works similarly, but it uses a transition within the nucleus itself, where the nucleus jumps between energy levels. Because the nucleus sits deep inside the atom, it's far less affected by external disturbances from things like electric or magnetic fields. According to Schumm, the nuclear transition can be 1,000 to 10,000 times less sensitive to environmental noise than atomic transitions are.

"This means that it would be easier to stabilize a nuclear clock over long periods of time," Jacob Higgins, a postdoctoral researcher at Northwestern University who previously worked on thorium clock experiments at JILA in Colorado but was not affiliated with the study, told Live Science in an email. "The transition used for the nuclear clock experiment has a higher quality factor than optical atomic clock transitions, which means that in principle, it can be measured more precisely given the same amount of measurement time."

Together, those advantages could allow nuclear clocks to outperform even today's best atomic clocks according to Higgins.

Why thorium-229 is special

The nuclear clock relies on a rare isotope called thorium-229, whose nucleus contains an unusually low-energy excited state that can be manipulated with ultraviolet laser light.

For decades, scientists had suspected thorium had a low transition, but identifying and controlling it proved extremely challenging. Researchers spent years testing different thorium-containing materials, laser systems and detection methods before finally pinning down the transition.

"It was a long road," Higgins said.

One key advancement was the development of continuous-wave lasers that operate at the precise wavelength needed to excite the thorium nucleus. Before those lasers existed, researchers had to excite the nucleus and then wait several minutes for it to decay and emit a detectable signal. That process was too slow to build a practical clock.

"With the continuous lasers, we can measure the nucleus in absorption and get an immediate response, whether the laser is still at the right frequency (and if not, correct it back)," Schumm said. "Once we had that, it was 'just' implementing some electronics and atomization to have the clock stabilize itself to the nucleus."

Thanks to this set-up, the researchers kept the nuclear clock running continuously for 24 hours.

Unlike many optical atomic clocks, which require ultracold atoms to be suspended in a vacuum chamber, the thorium nuclei are embedded inside a crystal at room temperature.

Because the thorium transition remains stable inside a solid material, researchers may eventually be able to build compact clocks that are useful for navigation systems, telecommunication networks and data synchronization.

A tool for studying the universe

Some physicists are more excited about what nuclear clocks could reveal about fundamental physics, rather than the clocks' timekeeping abilities.

Atomic clocks primarily probe electromagnetic interactions involving electrons. Nuclear clocks, by contrast, are sensitive to the strong nuclear force, weak nuclear force and electromagnetism — three of the four fundamental forces of the universe, along with gravity. This can make them useful detectors of new physics, in a way.

"The nuclear clock is foremost a different clock, ticking on different fundamental physics mechanisms," Schumm said. "Essentially all modern theories beyond the standard model predict additional particles or 5th forces … which can be probed with the nuclear clock in some parameter regime."

Thorium-229 is particularly intriguing because the energy difference between its two nuclear states results from a delicate balance between electromagnetic and nuclear forces. Because those large contributions nearly cancel each other out, even tiny changes in the underlying forces could shift the clock's frequency.

"So small shifts in these forces — like if the nucleus were to couple to certain forms of dark matter or if there were an oscillation of a fundamental constant — will be amplified in our measurement," Higgins said.

Researchers, including Higgins, have already used early versions of the clock to place constraints on some dark matter models, and they expect its sensitivity to improve as the technology itself gets better.

Although the first functioning nuclear clock is a major achievement, these timekeepers remain in their infancy. Scientists still need to gain a better understanding of how the thorium transition responds to factors like temperature and magnetic fields while developing more powerful and stable laser systems.

"I think it will be many years before the thorium clock can compete with today's best optical atomic clocks," Higgins said, "but we will learn a lot of new science on the pathway to getting there."

The San Andreas and San Jacinto fault systems are at their highest levels of tectonic stress in 1,000 years, raising the threat of a major, imminent earthquake that could devastate Southern California, a new study finds.

The faults could rupture separately or together, thanks to an "earthquake gate" between them at Cajon Pass, where the San Jacinto fault splits from the main trace of the San Andreas fault. Researchers discovered that Cajon Pass can prevent or facilitate earthquakes moving between the faults, depending on how similar their stress levels are at the time of rupture.

And right now, the San Andreas and San Jacinto faults appear to have comparable, extremely elevated stress levels, potentially spelling trouble for Los Angeles, San Bernardino, Riverside and the Coachella Valley, the team warned.

"Our results show that stress levels on multiple fault segments are now at or above the highest values seen in the past millennium and that the region may be capable of a large through-going rupture involving both fault systems," study first author Liliane Burkhard, a planetary geologist at the University of Bern in Switzerland and at the University of Hawaii at Manoa, said in a statement.

The San Andreas and San Jacinto faults have caused 36 earthquakes with magnitudes of 6.4 or above in the past 1,000 years. Southern California's last "big one" was a magnitude 7.9 event in 1857, when a 205-mile (330 kilometers) segment of the San Andreas fault slipped horizontally between Parkfield and Cajon Pass. That rupture did not propagate through Cajon Pass, but a similar megaquake in 1812 did, suggesting this could happen again in what is now a much more built-up and densely populated environment, according to the study.

Almost 170 years have passed since the 1857 megaquake, raising fears that another huge earthquake could be due to hit soon.

To estimate this risk, Burkhard and her colleagues built a model replicating the last 1,000 years of major earthquake activity along the southern San Andreas and San Jacinto fault systems.

The researchers used observations such as tree-ring records and age data from sediments that have been displaced to reconstruct Southern California's earthquake history. They fed this information into the model, which simulated the accumulation, release and propagation of tectonic stress in the San Andreas and San Jacinto faults.

The results, published June 3 in the Journal of Geophysical Research: Solid Earth, suggest the San Andreas and San Jacinto faults are primed for an Earth-shattering rupture, which may involve the earthquake gate at Cajon Pass opening to unleash more destruction than a single-fault event would on its own.

If a rupture were to occur along the two branches of the San Andreas fault that connect at Cajon Pass, it would be a joint rupture, according to the study. If both branches of the San Andreas fault and the San Jacinto fault were involved, this would constitute a tripartite rupture.

The chance of each event happening and the timing of a potential rupture are unknown, but understanding how much stress is building up inside the system could help planners and policymakers prepare for whatever comes next, Burkhard said.

"What we can say is that the system is critically stressed, and that physics-based models like this one give us a clearer picture of the range of scenarios we should be prepared for," she said. "That information matters for hazard assessment, infrastructure planning, and emergency preparedness."

The researchers say their model could apply to other fault junctions and be used as a tool for hazard assessment globally. "We are using rigorous, quantitative science to better understand the risk facing millions of people," Burkhard said.

An elusive dwarf fox that was feared extinct has been photographed for the first time, after being spotted near a highway in Cozumel, Mexico.

The tiny animal was part of the mysterious Cozumel fox population, a potentially undescribed species that had not been officially sighted in more than 20 years.

Cozumel foxes live only on Cozumel, an island near Cancún. Researchers know very little about these mysterious predators, which are roughly 20% to 40% smaller than their gray fox (Urocyon cinereoargenteus) cousins that live on the mainland.

Park and museum officials spotted and captured the fox in 2023 and, after a health assessment, released it back into the wild. Researchers have now shared the photographs and documented the encounter in a new study published May 4 in the journal Neotropical Biology and Conservation.

Although the rediscovery confirms that Cozumel foxes are still alive, they are likely on the brink of extinction, the study authors noted; the photographs highlight the need for focused research and conservation efforts.

"The biggest challenge facing the Cozumel fox is that we still know almost nothing about it, including its remaining population size, distribution, or ecology," study first author Travis Bayer, executive director of the conservation organization Pathos Wildlife, said in a statement. "That uncertainty alone is dangerous, because it makes effective conservation extremely difficult."

Cozumel foxes are an example of insular dwarfism, an evolutionary process in which larger animals, including fox-sized mammals, evolve to be smaller after colonizing islands, where there are limited resources and less space than on the mainland. The foxes aren't the only mammals that have shrunk on Cozumel over time; other examples include the island's critically endangered pygmy raccoons (Procyon pygmaeus) and dwarf coatis.

Archaeological evidence suggests that Cozumel foxes have lived on the island for at least 5,000 years, likely since before the arrival of the Maya within the past few millennia, and potentially for tens of thousands of years before that. Prior to this rediscovery, the last confirmed sighting of a Cozumel fox was in 2001, according to the study.

The rediscovery began with reports of a disoriented animal wandering near the highway on the southeastern side of the island. Officials with the Parks and Museums Foundation of Cozumel located and captured the fox, an adult male, on Sep. 14, 2023. They checked its health and later released the fox in the Laguna Colombia State Reserve, a protected area just south of where it was captured.

Recent and historical sightings suggest that Cozumel foxes could have an extremely restricted range in the island's South, where nature is increasingly threatened by development, land-use change, invasive species and natural disasters, the study authors noted.

The researchers recommended surveys to determine the current distribution and size of the Cozumel fox population, along with morphological and genetic assessments to establish its evolutionary status and conservation efforts to protect its assumed habitat in southern Cozumel and minimize human-wildlife conflict.

"Ultimately, we hope this work helps move the Cozumel fox from a little-known, uncertain presence on the island to a better-understood key part of Cozumel's ecosystems," Bayer said. "We also hope it demonstrates that conservation is often most urgent when certainty is lowest and that uncertainty itself can be a call to action."

Since it launched from Kennedy Space Center on April 1, 2026, we've been treated to some truly incredible photos of NASA's historic Artemis II mission, including a dump of 12,000 images captured by the crew. But a blurry snap, which shows the crewed Orion capsule as nothing more than a handful of black and white pixels, is a contender for the most impressive Artemis II photo — because it was captured by an Earth-based telescope more than 200,000 miles (320,000 kilometers) away.

This makes the photo a candidate for the longest-distance image of humans ever taken from Earth. (Images like the "Pale Blue Dot," which were taken from space, don't count.)

The trippy image, shared May 6 by the National Radio Astronomy Observatory (NRAO), was captured by the U.S. National Science Foundation Green Bank Telescope (NSF GBT) in West Virginia. NSF GBT consists of a 328-foot-wide (100 meters) radio dish on a circular rail, making it the world's largest fully steerable radio telescope. It played a key role in tracking the Orion capsule (nicknamed Integrity) throughout the Artemis II mission.

The pixelated photo shows the radio waves emitted by Integrity as it slingshotted around the moon at around 2,000 mph (3,200 km/h) ‪—‬ as fast as a speeding bullet. The camper-van-sized capsule was approximately 213,000 miles (343,000 km) away when the image was captured on April 6 (the sixth flight day of the mission), meaning it was on the same side of the moon as Earth. It was, therefore, taken either just before or just after the crew temporarily disappeared behind the moon's far side and broke the record for the farthest distance traveled from our planet.

At first glance, the photo might not seem striking, but when you start to think about what you're actually looking at and the technology required to capture it, it becomes much more impressive.

"There are four people in those pixels," Will Armentrout, a NSF GBT astronomer who helped track Artemis II, commented to his colleagues when they first saw the image, according to an NRAO statement.

Those four people were mission commander Reid Wiseman, pilot Victor Glover and mission specialist Christina Koch of NASA, as well as mission specialist Jeremy Hansen of the Canadian Space Agency — each of whom broke a different individual spaceflight record during the mission.

Tracking NASA's return to the moon

The Artemis II crew launched to the moon on board NASA's mega Space Launch System rocket and splashed down in the Pacific Ocean on April 10, after reentering Earth's atmosphere at around 25,000 mph (40,000 km/h) — the fastest speed any humans have ever traveled.

Throughout the mission, spaceflight enthusiasts watched the livestream from Earth, keeping tabs on everything that happened, from early toilet troubles and lunar meteor strikes to a touching tribute to Wiseman's late wife and a rather awkward interview with President Donald Trump. But they were not the only ones watching.

The NSF GBT team was also keeping a close eye on Artemis II and helped to accurately track the crew's progress during six-hour observation windows on each of the five days Integrity was closest to the moon. The telescope's extreme sensitivity and precision helped provide crucial data that will help NASA prepare for future Artemis missions, which aim to establish a base on the moon.

"With the GBT, we were able to track the movement of the spacecraft within 0.2 millimeters [0.008 inches] per second of what NASA calculated in its projections," Anthony Remijan, the NSF GBT's site director, said in the statement. "It's like having a speedometer in your car that can track your speed within 0.0004 decimal places per hour."

This is a great example of how scientific institutions across the globe contributed to the mission.

"To get big things done like we're doing in this capsule … you need a big team behind you," Hansen said during an interview while on board Integrity.

This article was first published May 14, 2026.

Artemis II quiz: Is your knowledge of NASA's historic moon mission out of this world?

This awesome astronaut photo shows the striking symmetry of "twin" stratovolcanoes at the heart of Java, Indonesia. The parallel peaks are an eye-catching reminder of the region's extreme tectonic activity.

Mount Sundoro (also known as Sindoro or Sindara) on the left of the image, reaches a maximum height of 10,331 feet (3,149 meters). Its partner, Mount Sumbing, sits to the southeast (on the right of the image) and is slightly taller, at 11,056 feet (3,370 m) above sea level.

Both are considered active. Although Sumbing has not erupted since 1730, Sundoro has blown its top more recently, in 1971, and has experienced seismic activity as recently as 2012, according to the Smithsonian Institution's Global Volcanism Program.

The volcanoes' peaks are just 7.5 miles (12 kilometers) apart. A raised ridge with a major highway runs perpendicularly between them.

Each volcano also has a smaller, secondary cone on its flank left over from previous eruptions (to the upper left of Sundoro and the upper right of Sumbing in the image), and their orientations make the volcanoes look like mirror images of each other.

The slopes of both cones are covered with rings of dark-green forest that sharply terminate at their bases. The volcanic soils surrounding the mountains are excellent for growing crops such as rice, corn, coffee and sugarcane, which has led to the deforestation of their surroundings, according to NASA's Earth Observatory.

This matching coloration accentuates the similarities between the pair, especially when viewed from above.

One of the few differences between Sundoro and Sumbing is that the latter volcano has a sizable crater at its summit, which was carved out by the 1730 eruption. As a result, the larger volcano appears to have a darker point at its top.

The volcanoes are commonly referred to as "twins," due to their near-identical profiles. However, local people often call them "husband and wife," according to a local travel site. In this narrative, Sumbing is considered the husband due to its slight height advantage and "more masculine" profile.

Sundoro and Sumbing are part of the wider Dieng Volcanic Complex, which consists of around 20 volcanic cones stretching across central Java. Indonesia is also positioned along the "Ring of Fire," a roughly horseshoe-shaped arc of volcanoes that runs along a series of tectonic plate boundaries encircling the Pacific Ocean.

Over the past few years, there have been a number of significant eruptions in Indonesia, including a pair of violent blasts at Mount Lewotobi Laki-laki, on Flores Island, in 2024 and 2025. As of June 2026, there are seven ongoing eruptions in Indonesia — the most of any nation.