This eye-catching astronaut photo mosaic shows a rare "sunglint" transforming a snaking reservoir into a giant silver river.

The winding waterway at the heart of this image is a section of Lake Powell in southern Utah. The artifical reservoir starts around 70 miles (110 kilometers) southwest of the town of Moab and ends roughly 60 miles (100 km) northeast of the Grand Canyon in Arizona. When full, Lake Powell holds up to 1.2 billion cubic feet (33.3 million cubic meters) of water, making it the second-largest reservoir in the U.S. — close behind the nearby Lake Mead, which stretches across the Arizona-Nevada border.

Lake Powell is located on the Colorado River, inside a steep ravine known as Glen Canyon. The reservoir emerged in the 1960s, following the construction of the Glen Canyon Dam, which caused water levels to rise by around 200 feet (60 meters) over the next two decades. In addition to generating hydroelectric power, the artificial lake has become a popular tourist destination. (Lake Mead is also located along the Colorado River and was created by the construction of the Hoover Dam.)

This image mosaic, which stitches together several astronaut photos into a single image, was captured during a sunglint, according to NASA's Earth Observatory. This phenomenon occurs when sunlight bounces off a reflective surface directly into the line of sight of an observer in orbit, such as a satellite or an astronaut, giving the object a metallic, mirror-like gleam.

Normally, this effect would be visible only across a small section of the lake. But by combining photos taken as the sunglint moved along the reservoir's length, the entire body of water was illuminated.

The reservoir is named after John Wesley Powell, an explorer and former director of the U.S. Geological Survey, who mapped out Glen Canyon and other parts of the Colorado River in the late 1860s. Powell was particularly captivated by Glen Canyon, which contained a "labyrinth of overhanging cliffs, hanging gardens, sweeping river bends, and natural arches set amidst a backdrop of colorful buttes and mesas," Earth Observatory representatives wrote.

Powell later described his recollections of the canyon. "Past these towering monuments, past these mounded billows of orange sandstone, past these oak-set glens, past these fern-decked alcoves, past these mural curves, we glide hour after hour, stopping now and then, as our attention is arrested by some new wonder," Powell wrote in his 1875 book "Canyons of the Colorado."

Some of the sights that Powell marveled over still exist, including many smaller canyons that branch off the reservoir and are cast in deep shadow. A similar effect is seen in sections of Utah's Green River, a tributary of the Colorado River that has long perplexed geologists due to its ability to flow "uphill."

From above, one of the canyon's most striking geological features ‪—‬ a large, doughnut-shaped depression known as The Rincon ‪—‬ is visible as a dark ring surrounding a bend along one of the widest sections of the lake. This rusty doughnut, which is up to 3 miles (5 km) across, is a former section of the Colorado River that dried out thousands of years ago when part of the canyon collapsed, enabling water to bypass the rocky loop.

However, many of the other wonders that Powell described have been lost beneath the reservoir's elevated water level. These include a side canyon dubbed the Music Temple, which was shaped in a way that gave it remarkable acoustic properties, according to the Earth Observatory.

During periods of drought, when the reservoir's water levels temporarily drop, other lost geological treasures can be exposed. For example, in 2023, researchers found rare fossils from a mammal-like Jurassic creature lurking beneath the lake's high-water line.

In recent years, some environmental groups have petitioned to drain Lake Powell and return Glen Canyon to its former glory as the "heart of the Colorado River," according to Newsweek. Such a change may help to alleviate pressure on the rest of the river, which has lost a significant amount of water in recent decades. But experts told Newsweek that this is unlikely to happen.

See more Earth from space

Mpox spread across the world in 2022, triggering tens of thousands of cases in countries where the infection was once rarely seen. Although the disease has since fallen out of news headlines, mpox (formerly called monkeypox) continues to circulate. Now, recent data suggests that the viral illness may soon be endemic to the United States, meaning it will circulate in the country consistently.

Previously, mpox cropped up sporadically in the U.S. via travelers who had visited African countries where the disease is endemic, as well as imported, infected animals that spread the virus to people. Cases have fallen substantially since the peak of the outbreak in 2022, but they haven't disappeared. A report published in August found that there were 2,800 cases in 2024 and over 2,500 in 2025, with only a small fraction being tied to travel. Nearly all of the viral samples analyzed were descendants of the strain that sparked the 2022 outbreak. In short, once the virus arrived, it never went away.

"There's no set threshold for what constitutes endemicity of monkeypox virus (MPXV) in the United States," Ryan Standford, an epidemiologist in the Centers for Disease Control and Prevention's (CDC) Poxvirus and Rabies Branch and co-author of the report, told Live Science in an email. "But each year provides further evidence of this transition."

Why is mpox still spreading in the U.S., and what can be done to snuff it out? It's likely that too few people have received two doses of the mpox vaccine JYNNEOS, which together are 66% to 90% effective. But beyond low vaccination, there may be other, less-understood factors that are contributing to the continued spread, experts told Live Science.

"We don't quite know how it's able to persist at such low numbers across the entire country," said Joel Wertheim, a professor of medicine in the Division of Infectious Diseases and Global Public Health at the University of California, San Diego.

At the same time, public health efforts around mpox have dwindled. Without a sustained effort on that front, it's unlikely the disease will be eliminated from the U.S.

"We have vaccines, testing, and a much stronger understanding of the disease than we did in 2022," Dr. Demetre Daskalakis, chief medical officer of Callen-Lorde, a LGBTQ+ community health center in New York City, told Live Science in an email. "Our focus now should be making sure those tools remain accessible, especially for communities that continue to face ongoing risk," said Daskalakis, who coordinated the nation's mpox response during the previous presidential administration.

"People at increased risk should know that mpox has not disappeared."

Who is at risk of mpox in the U.S.?

In the U.S., mpox is predominantly affecting men who have sex with men, and current vaccine recommendations are aimed at this group and their sexual partners. Mpox mostly spreads from person to person through close contact, and transmission during sex is playing a major role in the ongoing spread in the U.S.

Men who have sex with men are not more prone to mpox infection than anyone else. Rather, this transmission pattern stems from the outbreak beginning within a specific sexual network and then continuing to persist within the same network. "The mpox virus rediscovered the same transmission network that HIV had explored decades earlier," Wertheim said.

In a paper published in 2025, Wertheim and colleagues described the transmission dynamics of mpox in New York City during the 2022 outbreak. Similar to how HIV previously spread, mpox triggered "densely connected" clusters of infection. Then, as people in the network gained immunity via infection and vaccination, the cases petered out, decreasing to the persistent trickle we see now.

Wertheim noted that he's not surprised that mpox has remained largely confined to the same network, rather than leaping into new groups.

"From an evolutionary, ecological perspective, it's not hugely successful," Wertheim said. "It's sort of barely hanging on as an STI."

Why is mpox still circulating?

So if mpox is not hugely successful and we have a vaccine, how has the virus continued to circulate? One big factor is that too few at-risk people have been vaccinated, experts said.

The CDC's Center for Forecasting and Outbreak Analytics has crunched the numbers to see what percentage of that at-risk group needs to have immunity to stop mpox transmission, Daskalakis said. The at-risk group is estimated by counting the men who have sex with men who are either taking HIV-preventing medicines or have HIV, and then adding 25% to that total to account for additional people in the same sexual network. That estimate comes out to about 2 million people.

To prevent an outbreak bigger than the one in 2022, between 21% and 35% would have to have immunity through vaccination or a past infection. If over 50% of the group had immunity, that would mean there's a "very small probability" of sustained local transmission, the CDC's modeling suggested.

The current case counts suggest we haven't hit the 50% mark, or a total of roughly 1 million complete vaccinations or past infections.

Data from the August report on mpox seems to support the idea that too few people are vaccinated. That said, information about vaccination status was missing for about 62% of the reported cases. Among the remaining cases, 76% were unvaccinated, while 10% had gotten one dose and 14% had gotten two.

In a subset of 860 cases, the effect of vaccination was striking: Unvaccinated people had nearly 10 times higher odds of hospitalization due to mpox than fully vaccinated people did.

Waning public health attention

It's difficult to pin down exactly how many at-risk people are vaccinated, given that that data is no longer tracked at the national level. "My understanding is that there's no mandatory reporting on mpox vaccination data," Wertheim said.

The CDC previously monitored national vaccination trends, comparing the number of people vaccinated to the overall at-risk population. But that tracking stopped in early 2024, when about 23% of the at-risk population had been fully vaccinated.

Some states, such as New York, previously mandated that clinicians provide their state health department data on the number of people given mpox vaccines. But that reporting is now voluntary, a spokesperson for the New York State Department of Health told Live Science in an email.

Meanwhile, "as the emergency phase faded from public attention, awareness and risk perception may have declined," Daskalakis said. Public health messaging about the virus and vaccination has also waned.

"In recent weeks, HHS [the Department of Health and Human Services] has pulled down some of the plain-language guidance, which is not helpful in supporting messaging," Daskalakis noted. This decision to remove online resources about mpox reflects the federal government's current stance against addressing issues that affect LGBTQ+ health, he told Live Science.

Complicating factors

Although JYNNEOS substantially lowers the risk of severe mpox infection, the vaccine is not perfect, said Rachel Roper, a professor of microbiology and immunology at East Carolina University.

The virus typically enters the body through broken skin, the respiratory tract or mucous membranes (thin tissues found in the eyes, nose, mouth, anus and genitals). The mpox vaccine is good at generating systemic immunity, but it's not as good at guarding against the virus's immediate effects at those mucous membranes, said Roper, who studies poxviruses and vaccines against them.

Because mpox is largely spreading through sexual contact that involves those membranes, that slight gap in protection may also help to explain some of the ongoing spread, she suggested.

Plus, "there are also some data supporting asymptomatic infection as a possible route of transmission, making it more difficult to eliminate local transmission of mpox," Daskalakis said.

What can be done?

Given that mpox is already well established within some sexual networks in the U.S., "preventing endemicity entirely may be increasingly difficult," Standford told Live Science.

And notably, some federal funding cuts could undermine efforts to address mpox, Daskalakis said. These include cuts to Medicaid, mental-health services, housing programs, and HIV services such as the Ryan White HIV/AIDS Program.

Thankfully, looking at current mpox trends, "there's no indication we're returning back to 2022 levels," Wertheim told Live Science. So far in 2026, just under 1,000 mpox cases have been reported, according to the CDC. Month over month, the number of cases is generally trending downward. So, at a glance, the current situation seems better than it was in 2025, he said.

"We sort of seem to be on this razor's edge between endemicity and extinction," he said. "And it's not really clear which way it'll go."

Tipping the virus toward extinction will require healthcare providers to be informed and equipped to spot and manage cases, Daskalakis said. And communicating the importance of vaccination is key.

"One lesson from 2022 was that trusted messengers matter," he said. "We [at Callen-Lorde] work closely with LGBTQ+ communities and make information and vaccination opportunities available in settings where people already receive care." The clinic integrates conversations about mpox vaccination into routine health visits, sexual health services, HIV prevention programs and community outreach activities.

Beyond vaccinating at-risk populations, educating patients about how mpox spreads and how to reduce their risk is also key, Standford noted. "Vaccination coverage is a very important factor, but it is not the only one," he said.

Tipping mpox toward extinction will also require enough investment to maintain the disease surveillance, vaccination, testing and treatment capacity that the federal government helped to expand in 2022, Daskalakis said. The vaccine itself is now commercially available to clinics and in adequate supply, he emphasized.

"The fact that we're seeing ongoing circulation underscores the need for sustained prevention efforts rather than viewing mpox as a resolved public health issue," he said. "Infectious diseases don't disappear simply because public attention shifts."

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

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Mpox is an infectious disease caused by a poxvirus, meaning a virus in the same family as smallpox. The infection was formerly known as monkeypox.

Historically, mpox was endemic to Africa, and the virus consistently spread in the continent's central, eastern and western regions. In 2022, an unprecedented global outbreak spurred the widespread transmission of mpox in places that had seen only sporadic cases in the past.

Today, many countries affected by that outbreak — including Germany, Portugal and the United States — are still contending with local mpox transmission. Here's what to know about the virus, how it spreads and how to prevent infection.

What to know about mpox in the U.S.

Mpox is still spreading at low levels in the United States and may soon be considered endemic to the country. While case counts have fallen dramatically since the peak of the global outbreak in summer 2022, some people are still advised to get vaccinated against the virus.

Who should get vaccinated for mpox?

The mpox vaccine currently used in the U.S. is called JYNNEOS. One dose is about 35% to 86% effective, while the complete two-dose series is 66% to 90% effective. (The effectiveness varies, in part, because some studies include people with HIV and people without HIV, and inadequately treated HIV can undermine the body's response to vaccines.)

The JYNNEOS vaccine is not currently recommended for routine use in the general population because, beyond vulnerable groups, the risk is not high enough to warrant a universal vaccination strategy. The current outbreak is primarily affecting men who have sex with men, and those sexual networks are the primary targets for JYNNEOS vaccination.

However, not all men who have sex with men need to be vaccinated, according to the Centers for Disease Control and Prevention (CDC). Instead, vaccination is recommended for a specific subset of the group, including those who, in the last six months, have had more than one sex partner, have had sex at commercial sex venues, or have been diagnosed with other sexually transmitted diseases.

Nonbinary and transgender people with these risk factors are also recommended to get two doses of JYNNEOS, as are any sexual partners of anyone in the above groups.

Vaccines are also recommended after a suspected exposure to mpox, as they can help prevent or reduce the severity of the infection.

"For those who are eligible and have not yet completed vaccination, now is a good time to talk with a healthcare provider about getting protected," Dr. Demetre Daskalakis, chief medical officer of Callen-Lorde, an LGBTQ+ community health center in New York City, told Live Science in an email.

With the exception of laboratory researchers who work with mpox, people who have received two doses of JYNNEOS are fully vaccinated and do not need a booster, he said. And if a person has caught mpox in the past and recovered, they do not need to get a vaccine, he added.

About the virus

The poxvirus family also includes smallpox, which has been eradicated worldwide. Mpox and smallpox cause some similar symptoms, but mpox tends to be far milder than smallpox. However, the viruses are closely related enough that vaccines designed to prevent smallpox can also protect against mpox.

Mpox was initially named monkeypox because the virus behind the disease was discovered in captive monkeys in Denmark. But monkeys are not the main hosts of the virus in the wild; rodents and small mammals mostly found in West and Central Africa likely are. Health officials changed the name to mpox in 2022.

There are two major branches of the mpox family tree, called clade I and clade II. These clades were historically thought to have very different death rates, with clade I being the deadlier of the two. The case-fatality rate (CFR) of clade I has been estimated to range from 1.4% to over 10%, depending on the outbreak, while the CFR for clade II has been estimated at between 0.1% and 3.6%.

However, as both clades have spread beyond Africa, data suggests that the CFR for clade I may be lower than once thought, said Joel Wertheim, a professor of medicine in the Division of Infectious Diseases and Global Public Health at the University of California, San Diego.

The features of a given outbreak — such as the surrounding health infrastructure, patients' access to timely medical care, and the population's underlying risk factors for severe disease — likely play a big role in determining the virus's death toll, Wertheim told Live Science. In short, rather than being an immutable feature of the virus itself, the CFR is dependent on the underlying health of and resources available to a given population.

How mpox spreads

Mpox can spread from infected animals to humans through the animals' bites or scratches. Additionally, people can get the virus when they come into close contact with animals and/or their bodily fluids during hunting, skinning, trapping, cooking, eating animals or handling carcasses, the World Health Organization (WHO) notes.

The virus also spreads from person to person, primarily through very close contact, including intimate contact during sex. The virus typically enters the body through broken skin, the respiratory tract or mucous membranes (thin tissues found in the eyes, nose, mouth, anus and genitals), spreading via bodily fluids such as spit, mucus or blood. People can also pick up the virus via objects, such as clothing or linen, that are contaminated with the bodily fluids of an infected person.

The virus can spread through small respiratory droplets expelled during speaking or breathing. However, this is thought to be a less-common transmission route than close contact. There is also evidence that asymptomatic spread sometimes occurs, though it's unclear how frequently that happens.

Mpox can spread from mother to baby during pregnancy or birth. This route of infection can result in pregnancy loss, stillbirth, death of the newborn, or complications for the mother.

Symptoms of mpox

Symptoms of mpox typically appear within a week of a person being exposed to the virus, but they can sometimes take up to 21 days to develop. Once they emerge, symptoms last about two to four weeks, although the illness can linger longer in people with weakened immune systems.

Common symptoms include rash (see images), fever, sore throat, headache, muscle aches, back pain, swollen lymph nodes and low energy. Often, mpox rashes first appear on the face and then spread to other parts of the body; however, if a person becomes infected during sex, the rash may instead start around their genitals. The rashes begin as flat, discolored patches of skin and then progress into raised bumps, blisters, and large, pus-filled pimples that eventually scab over and fall off.

Some people with mpox develop painful swelling of the rectum (proctitis), while others have pain and difficulty when peeing (dysuria) or when swallowing.

Mpox rashes can make people vulnerable to bacterial skin infections, which can cause abscesses or other serious skin damage. Additional complications of the illness include pneumonia, infection of the cornea that can cause vision loss, and vomiting and diarrhea that causes dehydration or malnutrition. Mpox can also lead to blood infections, the intense immune reaction sepsis and, rarely, brain infections (encephalitis) or heart inflammation (myocarditis).

Children, pregnant people, and people with weakened immune systems, including from HIV infection, have a higher risk of serious illness and death from mpox.

Mpox prevention measures

Beyond vaccination, other strategies to decrease the risk of mpox infection include washing hands frequently, avoiding contact with contaminated objects and materials used by people with mpox, avoiding contact with other people's scabs or rashes, and using condoms, although they may only reduce, not eliminate, the risk of mpox exposure during sex.

Mpox treatment

Mpox treatment aims to manage a person's rashes and pain while also preventing complications. "Early and supportive care is important to help manage symptoms and avoid further problems," according to the WHO.

There is no antiviral drug approved for use in mpox, although some are available for emergency use in various countries. For example, the U.S. allows the use of certain smallpox medicines for mpox.

Severe mpox infections also may be treated with vaccinia immune globulin intravenous, which contains antibodies taken from the blood of people who were immunized against smallpox.

People who have recently been exposed to mpox can be given an mpox vaccine to reduce the severity of their symptoms or to prevent the illness altogether. This approach is known as post-exposure prophylaxis, or PEP.

"Post-exposure vaccine should be given as soon as possible, ideally within 4 days of exposure; administration 4 through 14 days after exposure may still provide some protection against monkeypox," the CDC states.

On Sept. 20, the Antarctic ozone hole peaked at 10.6 million square miles (27.4 million square kilometers), the second-largest size ever observed for this time of the year.

The last time the ozone hole was this big was in October 2015, when it reached a whopping 10.8 million square miles (27.9 million square km), records from the Copernicus Atmosphere Monitoring Service show. So why is the hole in the ozone layer — the shield that protects life on Earth from harmful ultraviolet solar radiation — so big this year, despite other clues telling scientists that it is recovering as expected from the damage human-made chemicals did in the 20th century?

The ozone hole's extent is due to extremely low temperatures in the stratosphere, but it's also possible that we could be seeing a new long-term trend of large, persistent holes, experts told Live Science.

"This year's ozone hole shouldn't be a cause for alarm," Hannah Kessenich, a postdoctoral physicist at the University of Otago in New Zealand who predicted the 2026 ozone hole's extent using satellite data and a computer model, told Live Science in an email. "However, there are still many unanswered questions. It's something we need to keep a close eye on."

Accurate predictions

The latest figures from the Copernicus Atmosphere Monitoring Service indicate that the size of Antarctica's ozone hole has dropped to around 9.3 million square miles (24 million square km) since Sept. 20, making it unlikely that this year will break the 2015 record. However, scientists think the hole will remain large and fluctuate over the next few weeks, Kessenich said.

Antarctica's ozone hole expands every year during the Southern Hemisphere's winter and spring. It typically reaches its maximum size between mid-September and early October, when temperatures are still freezing in the stratosphere and sunlight illuminates the frozen continent for the first time after months of darkness. The hole then shrinks again until late January as surrounding ozone-rich air mixes into the depleted region.

Antarctica's ozone hole was caused by emissions of ozone-destroying chlorofluorocarbons (CFCs) between the 1930s and late 1980s. These chemicals increased concentrations of chlorine in the stratosphere, thereby promoting a reaction that depletes the ozone layer. While countries signed the Montreal Protocol to phase out CFC use beginning in 1989, major CFCs have atmospheric lifetimes of 50 to 100 years, so the hole's recovery could take six decades, researchers estimate.

The ozone layer is particularly vulnerable above Antarctica due to the frigid conditions in the polar stratosphere. Temperatures below minus 108 degrees Fahrenheit (minus 78 degrees Celsius) trigger the formation of high-altitude clouds, whose icy surfaces turn inactive chlorine into its ozone-destroying form in the presence of sunlight. These conditions don't exist to the same extent in the Arctic, because warmer air from the midlatitudes mixes more readily with cold Arctic air than with Antarctic air, thereby blocking the formation of high-altitude clouds.

Changes in the polar vortex

This year's large ozone hole is caused by a very strong polar vortex, a wall of wind that encircles Antarctica and the Southern Ocean in the winter, trapping cold air above the continent. The polar vortex created colder-than-usual conditions in the stratosphere over Antarctica, accelerating the growth of the ozone hole.

Researchers haven't detected an increase in reactive chlorine, but the colder polar vortex has triggered more ozone depletion than usual, said Susan Solomon, a professor of chemistry and environmental studies at MIT who pioneered the study of Antarctica's ozone hole in the 1980s.

This size of this year's ozone hole is most likely a product of natural variability in atmospheric dynamics, Kessenich said.

"We expect ups and downs in the size of the hole from year to year," Solomon told Live Science in an email. "A year or a few years of bigger or smaller holes doesn't tell us anything about ozone loss or recovery; it is just variability. We have to look at the longer term trends, and those metrics continue to tell us that the ozone hole is slowly recovering as expected."

It's also reassuring that the ozone hole, while large, isn't as "thin" as in years past. The hole's extent is calculated based on the area above the continent with ozone values below 220 Dobson units, a measure of how many ozone molecules occur in a vertical column through Earth's atmosphere. Although the area of this year's ozone hole is huge, ozone values haven't dropped as low as in previous big-ozone-hole years, suggesting that there is less ozone "missing" from the hole compared with those years, Kessenich and her colleagues wrote in The Conversation.

But there's also the possibility that we've shifted to a new long-term trend of big ozone holes persisting until late spring, Kessenich said. Changes in global atmospheric dynamics unrelated to CFCs could be making longer-lived holes more likely, she and her colleagues wrote in the article.

There is also some evidence that climate change will strengthen the Antarctic polar vortex over time, which could lead to colder temperatures in the stratosphere and greater ozone losses in the spring, Kessenich said. If this year's polar vortex stays robust, the ozone hole could remain large well into November, she noted.

"It's too soon to tell what has been driving dynamical variability in recent years, but more research is needed," she added.

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You may have watched the moon block out the sun during a solar eclipse, but have you ever seen it do that to a planet? Early Tuesday (Oct. 6) morning, skywatchers across much of eastern North America will have an opportunity to watch a crescent moon pass directly in front of Jupiter. The rare alignment won't happen again for 11 years.

During the event, known as a lunar occultation, Jupiter will disappear behind the moon for up to about an hour before suddenly reappearing. The occultation will be visible before dawn from much of the eastern and central U.S., Canada and the Caribbean, while parts of Africa will experience the event during daylight, according to In-The-Sky.org.

The moon will be a beautiful waning crescent, just 20% illuminated, and Jupiter will shine brightly alongside it. The pair will rise together in the east early Tuesday morning and gradually appear to move closer as the moon travels eastward against the background stars.

When the occultation begins, Jupiter will remain hidden behind the moon for roughly an hour. No telescope will be needed to watch Jupiter disappear and reappear. However, a pair of binoculars or a small telescope will make the event much more dramatic.

Through a telescope, Jupiter will look like a tiny disc rather than a point of light and will take about a minute to disappear completely behind the moon. An easy way to photograph the event is to use a smart telescope to image the moon. (Here's everything you need to know about lunar photography).

Below are the times when Jupiter will disappear and reappear in 10 major cities Tuesday morning, according to the International Occultation Timing Association.

• Chicago: 3:22-4:17 a.m. CDT
• Atlanta: 4:15-5:17 a.m. EDT
• Detroit: 4:16-5:20 a.m. EDT
• Miami: 4:20-5:09 a.m. EDT
• Washington, D.C.: 4:20-5:24 a.m. EDT
• Philadelphia: 4:22-5:26 a.m. EDT
• New York: 4:23-5:27 a.m. EDT
• Toronto: 4:25-5:22 a.m. EDT
• Boston: 4:26-5:30 a.m. EDT
• Montreal: 4:30-5:26 a.m. EDT

Outside the occultation path, Jupiter won't disappear at all. Instead, it will appear to be skimmed by the crescent moon — still a potentially spectacular sight that could produce some amazing photos. From across much of the world, the crescent moon and Jupiter will appear exceptionally close together.

The next lunar occultation of Jupiter visible from North America will occur on Nov. 27, 2037, according to When The Curves Line Up.

The ancient Egyptians practiced human sacrifice around 5,000 years ago, a period shortly after the country was first unified, a new study finds.

In the new study, Roselyn Campbell, an anthropology researcher at Purdue University, re-examined 46 skulls from individuals who were buried near royal tombs that belonged to King Djer, King Djet and Meretneith (a woman who likely ruled Egypt at times), and were built near the ancient sacred city of Abydos. All three rulers lived during the first dynasty, a period that started around 5,000 years ago when Upper Egypt and Lower Egypt were unified into one kingdom. The sacrificed retainers were buried next to the tomb of the king they had served.

Researchers first excavated the royal burial site in the early 20th century. At the time, the excavator, Flinders Petrie, believed that the hundreds of other burials found near the royal tombs contained nonroyals, such as retainers and other people who served the king. Moreover, it appeared that these nonroyals had been sacrificed after the king they had served died, in the belief that they could serve the king in the afterlife.

However, Petrie was unable to identify evidence of fatal skeletal trauma, and his idea that they were sacrificed has been debated ever since. Petrie reburied most of the human remains, but 46 skulls were retained and preserved in the Duckworth Collections at the University of Cambridge.

In the new study, published Monday (Oct. 5) in the journal Frontiers in Environmental Archaeology, Campbell re-examined these 46 skulls using modern forensic techniques and information about the marks that different types of trauma leaves on human skeletons. Campbell found that 18 of the skulls have signs of trauma that were likely fatal — indicating that these individuals were likely sacrificed, according to a statement from the journal. Specifically, Campbell found that many of the skulls had linear fractures, which Petrie had mistaken for damage that occurred after burial.

Linear fractures "occur when the cranium strikes or is struck by a relatively large object with low overall force; because of the cranium's globular shape, the impact of the blow disperses across the cranial vault," Campbell wrote in the study. "While linear fractures are not always immediately lethal, they often cause intracranial lesions and/or hemorrhage, which can quickly cause loss of consciousness and death if surgery [to relieve pressure] is not performed."

Campbell told Live Science in an email that it's difficult to identify the weapon or object that was used. "Based on comparative forensic and archaeological studies, the most likely implement would have been flat and relatively light, probably made out of something like wood rather than stone," she said.

The practice of human sacrifice seems to have ended in the second dynasty of Egypt. Evidence for human sacrifice is limited and seems to be confined mainly to the first dynasty. Petrie theorized that they were retainers to the king based on the fact that some were buried with gravestones that had titles such as seal-bearer which suggested that they served the king.

"As far as we can tell, this particular type of retainer sacrifice seems to have ended with the close of the First Dynasty, which means it [lasted] around two centuries or possibly less," Campbell said.

Jacobus van Dijk, an Egyptologist at Groningen University in the Netherlands who was not involved with the study, welcomed the new research. The "existence of retainer sacrifice in early Egypt has always been controversial and Dr Campbell's research adds an important argument in support of scholars who, like myself, believe this custom was practised in Egypt in the early dynastic period," he told Live Science in an email.

He noted he was surprised at the method used for human sacrifice, because depictions of ritual killing on wooden labels "seems to indicate that the victim was kneeling with his hands tied behind his back being stabbed in the chest with a knife."

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Archaeologists have discovered a temple dedicated to the Roman war god Mars in the wooded foothills of the Taunus mountains in Germany. The temple was part of a military settlement that was built in the third century to defend the border of the Roman Empire against Germanic tribes.

The Roman military constructed thousands of forts across Europe, northern Africa and western Asia while expanding the empire, and most of these fortifications had an adjacent settlement, called a "vicus," that was occupied primarily by merchants, families and other civilians.

Since 2024, archaeologists have been excavating the Kapersburg Roman fort and its adjacent vicus in Hesse, roughly 16 miles (26 kilometers) north of Frankfurt, according to a Sept. 25 translated statement from the Hessen State Office for Monument Preservation.

One of the highlights of the current excavation is the unexpected discovery of a Roman temple, Kai Mückenberger, an archaeologist with Hessen Archaeology, a part of the Hesse State Office for Monument Preservation, said in a translated video. "Inside the temple, we found several fragments of a dedicatory inscription," he said. Experts have already translated a portion of the inscription, which mentions that the temple was dedicated to Mars, the Roman god of war.

"We also have the remains of a Mars [statue]," Mückenberger said, as well as a statuette of "a winged figure holding a palm branch and laurel wreath," which is likely the ancient Roman goddess Victoria, a personification of victory in battle.

When archaeologists first excavated the Kapersburg fort near the turn of the 20th century, they discovered that it was built in the early second century, likely under either Emperor Trajan, who ruled from A.D. 98 to 117, or Emperor Hadrian, who reigned from A.D. 117 to 138 and expanded the Roman Empire further into northern England, building Hadrian's Wall. The Kapersburg fort was used by a unit of Roman soldiers and cavalry for about a century and a half, until around A.D. 275.

Although the fort's defensive structures and some of its walls have been visible since antiquity, practically nothing was known about its nearby vicus prior to the excavations that began in 2024, according to Mückenberger.

"The astonishing thing is the exquisite preservation of the archaeological layers that start right beneath the forest floor," Mückenberger said. These layers, which include burnt material, almost never survive in agricultural areas but have been well preserved at the vicus. "This is an incredible learning process and a gain in knowledge for us," Mückenberger added.

During their excavations, the research team discovered far fewer houses than they expected. However, they found much more evidence of craft activities, such as blacksmith pits and ovens for drying wheat and baking bread.

"These are all very technical elements related to local services, indicating that we're in a kind of intermediate area not directly adjacent to the fort itself, but perhaps more like the fort's craft area," Mückenberger said.

The temple and votive statues provide new insight into the Roman world of beliefs on the border of the empire, according to the statement. But when the fort was no longer useful, the Romans leveled the camp and replaced it with residential buildings, the archaeologists discovered.

Mückenberger and his team plan to continue their excavation of the site next year.

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

This colorful ceramic urn depicts a person wearing a jaguar costume and surrounded by human skulls, about to be received into the Maya underworld. The urn once held the bones of an ancestor for their descendants to venerate.

The urn was anonymously gifted to The Walters Art Museum in Baltimore in 2008. According to the museum, the urn is about 17.5 inches (44.5 centimeters) tall and was likely produced in Guatemala by the K'iche' Maya people more than a millennium ago. Originally, the urn probably had an elaborate lid that was tied on with string through the loops near the lip of the vessel, but it is now missing.

The decoration on the urn is striking. A person wearing a jaguar costume splashed with blood — claws and teeth bared — looks out at the viewer from the center of the urn. This individual may be a deceased ruler who is entering the world of the dead, which is symbolized by two pairs of human skulls and the dark figures of two Maya gods of the underworld. Behind the underworld gods are raised spikes representing thorns of the tropical kapok tree (Ceiba pentandra).

The Maya believed that the kapok tree, which was also called the Maya "world tree" or the Yaxche, had roots in the aquatic underworld, so its depiction on this funerary urn may reflect how it is a conduit between realms, according to The Walters Art Museum. Jaguars also held important spiritual meaning to the Maya; they were thought to move fluidly between the three realms — sky, Earth and underworld. Therefore, the depiction of the deceased ruler wearing a jaguar costume to enter the underworld may have suggested that they could also mediate between the world of the living and the Maya gods.

This colorful and symbol-laden urn shows that death was not an ending for the Maya, according to The Walters Art Museum, and that the urn "serves as a graphic reminder of how the dissolution of the body could be a positive change, transforming a beloved ancestor into an honored spirit who would continue to guide the living for eternity."

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

Can you put together last week's Astonishing Artifact?

Researchers have developed a new type of interconnected architecture for quantum computing chips, and it could pave the way for machines capable of large-scale processing, including those with over a million qubits.

In a study published June 15 in the journal APL Quantum, scientists aimed to resolve a huge problem with the leading quantum processing units (QPUs): Qubits struggle to communicate and share quantum information with each other if they aren't immediate neighbors.

That's why the scientists pioneered Quantum Phononic Links (QPLs) — an approach for long-range coupling between qubits that leans on phonons — quasiparticles that carry vibration energy — to convey information. By contrast, conventional methods, like surface acoustic waves — high-frequency sound vibrations — demand complex designs and extra hardware.

"One of the key challenges in quantum computing is long-range qubit connectivity," Maksym Myronov, an associate professor of semiconductor materials and devices at the University of Warwick in the U.K. and first author of the study, said in a statement. "Our work introduces a new concept in which phonons act as a quantum bus, enabling distant qubits to exchange quantum information while remaining fully compatible with semiconductor technology."

In the study, the scientists said the most promising way to achieve a quantum computer that's capable of large-scale processing and takes advantage of QPLs would be a qubit modality known as "semiconductor hole spin qubits."

A "hole" here refers to the absence of an electron in a material, but it can act like a particle and have a spin state — a property used to encode quantum information — where the 1s and 0s of data would be represented by the direction of the particle's spin state.

To demonstrate this technology, they created a prototype QPU consisting of silicon with a thin germanium crystal layer, a specialized material they called compressively strained germanium on silicon (cs-GoS). Germanium is an especially useful material for quantum computing, the scientists said, as it has natural properties that reduce decoherence — the loss of quantum information due to external interference.

Hole spin qubits combine long quantum coherence times — how long they can retain quantum information — with the ability to communicate using electron impulses in control systems. But they struggle to form bonds and share quantum information with qubits they don't directly neighbor. In any large-scale system, for instance, enabling this "quantum coupling" between distant qubits is essential for quantum error correction techniques to work effectively across the breadth of a massive system, the scientists said.

Other proposed long-range communications approaches, such as "charge shunting" — redirecting capacitors to reduce sensitivity to charge noise, or surface acoustic waves — have fundamental limitations regarding scalability, both in terms of their size and in maintaining coherence. That's where QPLs come in.

QPLs are engineered phononic waveguides and cavities that both confine and guide acoustic modes within a compressively strained germanium "quantum well," where a quantum well is an ultrathin layer that acts as a guide.

In the study, the researchers focused on qubits using valence-band holes — the absence of electrons at absolute zero — hosted using cs-GoS. With QPLs, the scientists sent sound-like vibrations through the specialized material to carry quantum information between the distant qubits.

Spin states in this material are highly sensitive to lattice deformations, which enable precise control and the coupling of spin states with vibrational energy. Essentially, this allows the spin state to be distinguishable from its electron counterpart, enabling the phononic coupling strategies. The technique they adopted permitted direct coupling between the phonons and the hole spins.

By using a slow wave velocity (the speed of a quantum particle) and a short wavelength for acoustic excitations, the scientists used QPLs to link qubits separated by less than a micrometer (one-thousandth of a millimeter) and those up to 300 mm (11.8 inches) apart.

QPLs are not only promising for quantum computing, the scientists pointed out in the study. By utilizing phonons as the connections, this technique offers a versatile interface for hybrid quantum systems — conventional computers with quantum computing functionality. This could enable coherent interconnection of semiconductor spin qubits with other quantum platforms, such as cloud-based quantum computing.

The combination of phononic engineering and hole-spin physics makes cs-GoS a promising platform for next-generation quantum architectures, they added, since it could achieve both long-range coherent coupling and large-scale integration.

Can you match these ancient devices to their pictures? Find out with our computing quiz!

Physicists smashed gold nuclei together at nearly the speed of light and found an unexpected pattern in the particles these collisions sprayed out. If confirmed, that pattern could help reveal how the hot soup of quarks and gluons that filled the universe in the first few microseconds after the Big Bang cooled and condensed into the protons and neutrons that make up ordinary matter today.

In every collision, particles are flung out sideways; how hard they are flung, on average, varies slightly from one collision to the next. Physicists expected the size of these variations to change smoothly as they adjusted the collision energy. Instead, the variations dipped, shrinking and then growing again. This dip could be a sign of a long-sought "critical point," a special set of conditions at which nuclear matter changes the way it transforms from one form to another.

The signal, detected by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory in New York, is strong enough that it is very unlikely to be a statistical accident. However, the researchers cautioned that the dip is a tantalizing hint, not proof of the long-sought transition. They published their findings Sept. 22 in the journal Physical Review Letters.

A rulebook for extreme matter

Protons and neutrons are made of smaller particles called quarks, which are held together by the "strong force" carried by particles called gluons. When heated or squeezed enough, protons and neutrons melt into a hot soup of free quarks and gluons known as a quark-gluon plasma. It's thought that this primordial soup of particles filled the universe in the first milliseconds after the Big Bang.

Physicists want to pin down how this soup-ification happened, by measuring the so-called equation of state of nuclear matter. "For water, it tells you how pressure, temperature and density are linked, and therefore when it freezes, boils or expands," study co-author Rutik Manikandhan, a postdoctoral physics scholar at The Ohio State University, told Live Science in an email. For nuclear matter, "it is the basic rulebook for matter under the most extreme conditions in nature, such as the cores of neutron stars," Manikandhan added.

The "critical point" is a key landmark in that rulebook "For water, it is the point where the boundary between liquid and steam disappears," Manikandhan said, and theorists have long suspected that nuclear matter has a similar point. At extremely high temperatures, matter melts smoothly and gradually into quark-gluon plasma, but at higher densities, the change may become abrupt.

The critical point would mark where one kind of transition turns into the other. Some recent calculations place this point within reach of RHIC's lower-energy collisions. "But all of this is still conjectured and there is nothing concrete yet, either from the experimentalists or theorists," Manikandhan said.

The work also matters for cosmology. "Because the matter we create in these collisions resembles the matter that filled the universe a few microseconds after the Big Bang, mapping how it behaves helps us understand how the universe evolved from a hot soup of quarks and gluons into the protons and neutrons that make up everything today," Manikandhan said.

A dip where a smooth trend was expected

To explore this territory, the researchers ran RHIC at a range of collision energies. The lower the energy, the more tightly the colliding matter was squeezed. For its lowest-energy runs, STAR used a "fixed-target" setup, in which a beam of gold nuclei strikes "a thin gold foil placed inside the detector," Manikandhan said, instead of a second, oncoming beam. This produces the densest matter RHIC can make.

Collision energies are measured in electron volts (the energy an electron gains when accelerated across 1 volt). That is a minuscule amount, so particle physicists usually work in billions of electron volts, or giga electron volts (GeV). One GeV is roughly the energy locked up in the mass of a single proton, according to Einstein's famous equation E = mc². The team analyzed roughly 1 billion collisions at energies between 3 and 7.7 GeV per pair of colliding protons or neutrons. That is the bottom of RHIC's range, which reaches 200 GeV.

In each collision, the team measured how hard charged particles were flung sideways out of the fireball ‪—‬ a quantity known as transverse momentum. The researchers then looked for correlations between the particles. A correlation measures whether two things tend to change together. Here, the team checked whether pairs of particles from the same collision tended to both be flung harder than average, or both more gently. That reveals something about the fireball as a whole. If a fireball is slightly hotter, or expands more forcefully, all of its particles get an extra sideways kick together.

"Those correlations reflect how much the temperature and the flow of the fireball fluctuate," Manikandhan said.

Close to a critical point, the matter's heat capacity — the amount of energy needed to raise its temperature — is expected to shoot up. That makes the fireball's temperature harder to budge, so the correlations should weaken. "If the matter approaches a critical point or a phase change, we would expect to see those correlations change in an unusual, non-smooth way as we vary the collision energy," Manikandhan said.

That is what the team saw in the most head-on collisions. "Instead of changing smoothly with energy, the correlations show a dip," Manikandhan said. The researchers compared the data with a smooth trend anchored by earlier STAR measurements at higher energies. The dip departs from that trend with a statistical significance of 5 sigma, the standard physicists usually demand before treating a signal as real. It means that if the true trend were smooth, random scatter in the data would produce such a pronounced dip only about once in 3.5 million tries.

"A smooth trend is what you'd expect from ordinary nuclear matter, so a dip suggests something more interesting is happening at those conditions," Manikandhan said.

By contrast, a widely used computer simulation of the collisions, which contains no critical point, reproduced the overall trend but not the dip. Off-center collisions showed only a faint hint of the same feature, which is too weak to count as evidence on its own.

Not the final word yet

"The result is suggestive, not proof of a critical point," Manikandhan said. Effects unrelated to a critical point can also shape these fluctuations, and how much of the dip they could explain remains unclear, the researchers noted.

Still, the dip "does point to a set of conditions where the behavior of nuclear matter changes, and it gives theorists a new, precise measurement to test their calculations against," Manikandhan said.

Next, the team plans to use the correlations to "extract the specific heat of the hot matter," Manikandhan said. They will then compare it with supercomputer simulations that calculate the behavior of quarks and gluons from first principles.

The researchers also plan to test the dip against more theoretical models and combine it with other measurements, such as fluctuations in the number of protons produced in the collisions. "Only when different measurements agree can we say confidently whether a critical point exists," Manikandhan said.

The debut images from a new Earth-observing satellite have just given us a view of the impossible: giant auroras rippling over the North Pole in broad daylight.

Earth's auroras are one of our planet's signature wonders — a sight worth advertising in interstellar travel guides, alongside our perfect total solar eclipses, bright shooting stars and majestic blobfish. They are the beautiful result of electrical storms in the atmosphere, appearing when charged solar particles skate along Earth's magnetic-field lines and collide with light-emitting molecules near the poles. (Auroras do exist on other planets, but they are usually not in bright visible colors like ours.)

To human eyes, auroras come out only at night and rarely stray from the poles. That's what makes these first observations from the joint European-Chinese Smile mission, which officially began science operations this week, so special.

Captured in ultraviolet light, the stunning images show a huge, serpent-like ring of charged particles coiling around the North Pole in July 2026. In the foreground, Earth appears ghostly and featureless, glowing like a half moon. The aurora writhes around our planet's sunlit side, covering about a third of it, while Earth's dark nightside bleeds into the background sky. Far behind, bright stars fall like raindrops as Smile shifts subtly in its orbit.

The view alone is worth smiling about, but the new images also promise exciting science to come. Taken just two weeks after scientists first turned Smile's Ultraviolet Aurora Imager on, the observations show that the satellite's instruments are working as they should and that the joint European Space Agency (ESA) and Chinese Academy of Sciences mission can officially begin.

Launched on May 19, Smile will spend the next three years watching Earth from a highly elliptical orbit that takes it about 75,000 miles (121,000 kilometers) over the North Pole — about a third of the way to the moon. From there, Smile can observe the North Pole for a record-breaking 45 hours at a time, offering an unprecedented view of solar activity there.

In addition to the Ultraviolet Aurora Imager, Smile carries three more science instruments to detect X-rays, magnetic fields and light ions over Earth.

This week, scientists also tested the spacecraft's soft X-ray imager by pointing it at the distant supernova remnant Cassiopeia A, located about 11,000 light-years from Earth (image above). Although the camera is working fine, the detector is still picking up a bit too much light when aimed at Earth, so it will require a bit more calibration from scientists on the ground.

In 2023, an African gray parrot named Jack went viral for mimicking the coughs and wheezes of her owner's father, who often struggled to breathe from severe chronic obstructive pulmonary disease.

But it wasn't just the imitation that made Jack famous; it was also that she seemed to relish the suffering of a man she purportedly hated. In the video, Jack's owner even claimed that she had a favorite cough.

The parrot appeared to be experiencing a complex emotion that in humans is known as schadenfreude, or pleasure at seeing another's pain. Literally translated from German as "harm joy," it's a feeling that might emerge when a rival coworker gets fired, or when a rude neighbor has their package stolen.

When a cat seems a little too happy watching a human stub their toe, or a horse seems to grin at a person stepping in poop, their owners might also interpret their behavior as schadenfreude.

But can any animals really experience such a complicated emotion? Or is this a classic case of anthropomorphization?

A complex emotion

Animals probably do not experience schadenfreude, according to researchers who study animal behavior and intelligence. However, the question hasn't received much attention in formal research. That's partly due to limitations of animal behavior methodology, but also because the question is bound up with how we define and communicate emotion in the first place.

"The study of complex emotions is incredibly difficult when you're talking about an animal that cannot communicate their emotions linguistically," Zachary Silver, an assistant professor of psychology who leads the canine intelligence lab at Occidental College in Los Angeles, told Live Science. "We don't have the ability to be as precise as we like to be in the scientific community."

Silver explained that researchers can look at behavior, neurological signals or hormonal activity to make an educated guess about what an animal might be feeling. A dog that has its ears back and tail tucked, for instance, is probably experiencing a negative emotion, while one wagging its tail is feeling a positive one.

But "aside from positive and negative, without words to describe the emotion, it becomes very difficult to disentangle," Silver said. The dog could be happy, but it could also just be interested in something new. "It's just so hard for us to say with any definitive nature that we really can know exactly what emotion is going on there," Silver said.

Animal behavior researchers try to avoid anthropomorphizing animals ‪(attributing human qualities to them) without evidence. When a cat or dog comforts a grieving human, for example, it could just be that the behavior was previously reinforced by rewarding the animal with treats or pets, rather than a genuine outpouring of sympathy. Similarly, Jack the parrot could have been mimicking coughs just for attention.

To truly experience a complicated emotion like schadenfreude, an animal needs to understand the emotional states of both itself and others — a concept called theory of mind.

"Dogs may have some ability to attribute mental states like emotions, thoughts, beliefs, intentions to other individuals, but this really only occurs in very select contexts and in really kind of a rudimentary way," Silver said. Because of this, "it's exceedingly unlikely that dogs would be able to experience schadenfreude in the way that we as humans do."

David Stahlman, an animal behavior researcher at the University of Mary Washington, agreed that such emotional capacity in animals is unlikely. He said that animals do not seem to have the ability to recognize their own emotional states, though he noted that not all animal behavior researchers agree.

"There's a difference between the affect, the emotional behavior, and then the recognition of the emotional behavior in oneself," Stahlman said. If nonhuman animals were to have this capability, he suspected it would probably be found in highly social great apes, like chimpanzees (Pan troglodytes) and bonobos (Pan paniscus). Schadenfreude, in particular, would require animals to live in close social groups, since it requires knowledge of the individual experiencing the harm and whether it's deserved.

In hierarchical groups, it's possible that the suffering of one animal might benefit another and lead to something resembling happiness, Stahlman said, but he doubts this would ever qualify as true schadenfreude.

"The kind of Machiavellian stuff is a very human thing," he said.

Nevertheless, “there is a lot of data pointing in the direction that animals do have really deep capacities for emotional intelligence,” said Kaeli Swift, an animal behavior researcher at the University of Washington and author of the Corvid Research blog.

Swift noted that studies of some corvid species have found evidence of emotional recognition, fairness and "some of the strongest evidence across the animal world" for theory of mind. However, when it comes to studying an emotion as complex and subjective as schadenfreude, she said that researchers "haven’t quite crossed that threshold."

In the study of animal emotions, she said "we have barely started to scratch the surface."

About 1 in 8 cancer cases are caused by infections with viruses, bacteria or parasites, a new study finds, suggesting that one of the most effective ways to reduce cancer rates might be to prevent common infections.

In a new analysis published Sept. 28 in the journal The Lancet Oncology, researchers mapped the global impact of 12 cancer-causing pathogens. They estimate that infections drove about 2.3 million new cancer cases in 2024, or about 12% of all cancer cases diagnosed that year.

The study highlights that a large fraction of cancer cases could be avoided if these underlying infections were prevented, Dr. Prashant Mathur, director of India's National Centre for Disease Informatics and Research, who was not involved in the study, told Live Science in an email.

"When combined with other risk factors such as tobacco use, alcohol consumption, appropriate diet, physical activity, and environmental pollution, it is estimated that about 50 to 60 percent of all cancers in India are avoidable," he said. Past studies suggest that similar figures hold on a global scale.

In the new study, the researchers used the Global Cancer Observatory's GLOBOCAN database, which combines data from various cancer registries to estimate that about 20 million new cancer cases were diagnosed in 2024. The team combined that information with other published data examining the prevalence of different infections in people with specific cancers. This enabled them to estimate how many cases were attributable to each infection.

Their analysis focused on 12 pathogens tied to cancer, including human papillomavirus (HPV), hepatitis B and C, HIV and Epstein-Barr virus (EBV), the virus behind mononucleosis. The resulting breakdown revealed that just four pathogens accounted for roughly 92% of the cancer cases caused by infections.

A bacterium called Helicobacter pylori, which infects the gastrointestinal tract, accounted for 760,000 cases, primarily gastric cancers. The other three leading cancer triggers were viruses. HPV accounted for 750,000 cases, including cervical, penile, throat and mouth cancers. The liver-attacking hepatitis B virus was responsible for 360,000 cases and EBV drove 260,000 cases. (EBV is known to increase the risk of throat cancers, as well as certain lymphomas and stomach cancers.)

The scale of the burden contrasts with gaps in prevention. In 2024, just 31% of eligible adolescent girls worldwide received at least one dose of the HPV vaccine, well below the 90% target, the World Health Organization reports. The degree of protection provided by the vaccine is striking in countries that have achieved higher coverage.

"We have now achieved the critically important milestone of cervical cancer starting to disappear in countries that quickly achieved vaccination rates of over 80 percent," said Dr. Rebecca Perkins, an obstetrician-gynecologist at Tufts University School of Medicine who was not involved in the study. "Research from Australia, England, and Finland have shown zero cases of HPV-related cancers or deaths in young adults who received vaccination by age 13," Perkins told Live Science in an email.

But these successes are concentrated in wealthy nations. The Lancet study found that low- and middle-income countries bear 77% of the global infection-driven cancer burden. For example, about 81% of HPV-linked cancers occurred in these countries.

Perkins pointed out that shifting from the standard two-dose HPV vaccine series to a single-dose regimen using the same vaccines could make mass campaigns easier worldwide by lowering costs and eliminating the need to track patients for follow-ups. The single-dose approach has been backed by recent trials.

In the U.S., progress has been uneven across states with some boasting high vaccination rates and others lagging behind. One barrier is that some children's caregivers feel the shots are unnecessary or that their kids are too young to receive it. "The biggest misconception from families is that the HPV vaccine is not needed or that it can wait," Perkins noted. "The reality is that you can't vaccinate too early, only too late."

There is also a highly effective vaccine for hepatitis B, and health officials recommend giving children their first dose as soon as possible after birth. (The U.S. Centers for Disease Control and Prevention recently made the decision to stop recommending universal vaccination at birth, which experts say could raise the country's rates of hepatitis B infections and related cancers.)

While the challenge with HPV and hepatitis B is getting their vaccines into widespread use, there isn't an approved vaccine for EBV yet.

"The biggest hurdle has been the complexity of the virus," said Claire Shannon-Lowe, a tumor virologist at the University of Birmingham in the U.K. who was not involved in the study. "Unlike many other viruses that use just one or two virus proteins to enter cells, EBV uses multiple proteins ... and it hides inside cells for our entire lifetime."

Epstein-Barr infections are also incredibly common, with up to 95% of people infected by adulthood; most people infected with the virus don't develop a related cancer, but it's still a major contributor to the global cancer burden. The germ has also been tied to several autoimmune diseases, which may help spur the development of a vaccine, Shannon-Lowe suggested.

"With the increased impetus following EBV's association with multiple sclerosis and lupus, we may finally have a potential vaccine in sight that could not only prevent virus infection but could help treat EBV-associated cancers," she said.

For H. pylori, meanwhile, researchers are pursuing population-wide testing for and treatment of the infection to help prevent gastric cancer, while vaccine development remains an area in need of further investment.

The true scale of the infection-related cancer burden may be even larger than the study suggested. Some of the registries used in the new research cover only about 19% of the global population, and only 2% of Africa's population. More high-quality data is needed to fill in these gaps.

For Mathur, though, the bottom line is that cancer prevention makes economic sense.

"Studies have clearly demonstrated that the return on investment of prevention on cancers is much higher than on its treatment in the long run," he said. "Preventive aspects must be strengthened for long-term gains."

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

Mammals first appeared on Earth over 200 million years ago, scuttling around alongside the dinosaurs as little mouse-sized creatures. But after the asteroid hit 66 million years ago, it was their time to shine ‪—‬ and the Age of Mammals began.

But the path to understanding our own branch of the animal kingdom hasn't been straightforward. In this excerpt from "The Story of the Mammals in 25 Discoveries" (Columbia University Press, 2026), author Donald R. Prothero looks at a time when philosophers and early naturalists believed giants roamed the Earth and explores the idea that extinction was heresy.

Many cultures around the world have a mythology that includes legends about gigantic races of humans that lived on Earth in the dark mysterious past. They may have fought against the gods, or they may have been destroyed by floods. These stories were reinforced by the discovery of gigantic bones, much larger than those of any living human, all over the Mediterranean and Europe.

The Greek philosopher Empedocles (492-432 BCE) reported gigantic bones from Sicily, supposedly remnants of a race of giants. The Roman historian Pliny the Elder (23-79 CE) mentioned fossil ivory in the ground, and according to the Roman historian Suetonius (69- 122 CE), Emperor Augustus owned a collection of large bones that had been found on the island of Capri, near Pompeii. The skulls of elephants, with their huge central opening in front (for the trunk), were thought to be the skulls of the one-eyed cyclops.

In the Middle Ages, these huge bones were again attributed to gigantic humans or other monsters (Genesis 6:4) that were drowned in Noah's flood. Giant tusks from Siberia were thought to be the horns of the mythical unicorn or the tusks of dragons. In some places gigantic teeth or vertebrae of mammoths were revered as relicts of saints. Nearly every possibility was suggested except that they were the bones of extinct elephants.

In the early seventeenth century, some giant bones dug up in a sand pit near Langon in southeastern France were exhibited around France as the remains of the giant Teutons, Germanic tribes that once roamed Gaul and were defeated by the Romans in 101 BCE.

But in 1613 the famous anatomist Riolan attacked the prevailing interpretation, suggesting that they were the bones of an elephant. This generated a raging controversy between physicians and anatomists and the barber-surgeons who called them gigantic human bones. Others thought they were hoaxes or generated by mysterious "plastic forces" (vis plastica in Latin) that percolated through Earth. Still others attacked the anatomists for questioning the biblical account of giants on Earth. The controversies died down in 1618 without being resolved, and for the next two centuries most people continued to interpret new finds as gigantic humans.

The giant bones that kept turning up in the New World were also a source of much mystery and consternation. The Native American tribes usually attributed them to giant monsters fought by their ancestors and incorporated them into their folklore. When these bones were first seen by European settlers, they were thought to be the bones of gigantic humans that roamed the earth in biblical times. Others thought that the giant tasks so revered by the Native Americans were the works of Satan, placed there to tempt the believer.

In 1519, the Spanish explorer and conquistador Hernan Cortez received a bone of a "giant," a gift from the friendly Tlascalan tribe of Mexico during the conquest of the Aztecs. He sent it back to the King of Spain as proof that giants at once lived in the New World. In 1706, the Reverend Cotton Mather of the Massachusetts Bay Colony pronounced them to be "the remains of godless giants drowned in Noah's Flood." He sent some bones to the Royal Society in London to have them certified as evidence of this "wicked giant" because biblical scholars were calculating Adam's height at 123 ft. 9 in.

The Royal Society never pronounced an opinion on these bones, although by that time many members were becoming skeptical of the literal interpretations of Genesis. The stifling effect of religious dogma about giants and Noah's flood was complicated by another idea: the notion of Divine Providence. An omnipotent, benevolent God would never allow any of his creatures to become extinct. As the poet Alexander Pope wrote in An Essay on Man (1734), "who sees with equal eye, as God of all, a hero perish, or a sparrow fall."

The prevailing concept was that of a "great chain of being" that linked the animals to man to the angels to God. Breaking any link in that chain implied the destruction of the whole chain. In the same poem, Pope also wrote: "Where, one step broken, the great scale's destroy'd; From Nature's chain whatever link you strike, Ten or ten thousandth, breaks the chain alike."

By the late 1700s, however, it was becoming more and more apparent that many of the recently discovered fossils had no living counterparts. Remote corners of the world were being explored, and although many new and surprising beasts were discovered, clearly the gigantic beasts were not hiding in South America or Africa or the East Indies. Many strange fossils, such as the bones of hippopotami in Paris and London, were clearly related to tropical animals, but it was assumed that these bones had been washed from the tropics during the Great Flood.

The notion of extinction was still blasphemous. The New World soon provided unequivocal evidence that these large bones were not simply gigantic humans. In 1739, Charles le Moyne, the second Baron de Longueil, left Montreal with French and Indian troops to fight the Chickasaw Indians along the Ohio River. Somewhere along the Ohio he found the remains of what appeared to be three elephants. When the war ended in 1740, le Moyne collected the bones and shipped them to New Orleans and ultimately to Paris, where they came to the attention of French naturalists.

In the 1740s and 1750s, English settlers in the region sent more of these bones from Big Bone Lick, Kentucky, off to England and also to Benjamin Franklin in America. Most of the bones (especially the tusks) were clearly like those of elephants and mammoths, but the teeth were puzzling. They were clearly unlike any living elephant, yet they were part of an animal of elephantine size. (We now know that these were specimens of the American mastodon, Mammut americanum.) Franklin speculated that the teeth were reminiscent of a carnivorous animal, although he and others later decided it was a vegetarian.

In 1769, the famous British anatomist William Hunter took the carnivory suggestion seriously and suggested this was not a true elephant but a "pseudelephant" or "American incognitum" (Latin for "unknown") that had independently developed ivory tusks:

"This monster, with the agility and ferocity of a tiger . . . cruel as the bloody panther, swift as the descending eagle, terrible as the angel of night. . . . And if this animal was indeed carnivorous, which I believe cannot be doubted, though we may as philosophers regret it, as men we cannot but thank Heaven that its whole generation is probably extinct."

This very precocious suggestion was still not accepted by naturalists of the time. Nevertheless, remains of the "incognitum" and also of the Siberian mammoth (including frozen carcasses with hair and skin) were turning up again and again. Georges Louis Leclerc, the Comte de Buffon (1707-1788), concluded in his Théorie de la terre in 1749 that although most of the supposedly extinct animals were hiding somewhere in an unknown region, it was likely that the large terrestrial mammals such as the mammoth and "incognitum" had actually perished.

By 1778, Buffon was relating their disappearance to his ideas of violent cataclysms in Earth's early history. During this time the climate was warmer and polar regions had once been tropical, so "elephants" (meaning mammoths) could live in Siberia. This implied a nonbiblical Earth of much greater antiquity. Buffon suggested it was as much as 75,000 to 3,000,000 years old, rather than the 6,000 years demanded by most literalist biblical scholars.

Naturally, such revolutionary ideas were not popular with the theologians in the Sorbonne. Buffon was protected by the king, however, so he was not persecuted for his heresy, although his ideas were not widely accepted either. The fact of extinction was finally proved by one of the greatest scientists of all time, the Baron Georges Cuvier (1769-1832).

Jean Leopold Frederic Georges Cuvier was an impressive man. Tall of stature, he had a "massive" head crowned by a large mane of hair. One admirer wrote that his head "gave to his entire person an undeniable cachet of majesty and to his face an expression of profound meditation." After his death, scientists weighed his brain and found that it was a massive 1830 grams [4 pounds], more than 400 grams [14 ounces] above average, and 200 grams [7 ounces] heavier than any brain ever measured at that time.

More important, he was one of the most brilliant men of his time, with a command of many subjects, some of which he invented all by himself. Before Cuvier, natural history was a field that resembled stamp collecting, with many amateur naturalists compiling long lists and descriptions of new species without analyzing the similarities in their anatomy. Cuvier almost single-handedly revolutionized natural history by dissecting many different animals and discovering their underlying similarities and differences.

This became the foundation of comparative anatomy, a subject that has been fundamental to biology ever since. Naturalists and explorers sent him their fossil bones, and he was the first to correctly describe many types of extinct animals. Cuvier solved the mystery of the puzzling fossil teeth called the "Great Incognitum" and recognized them as the teeth of the elephant-like mastodons. He also correctly deciphered the huge marine lizards we now know as mosasaurs.

For this reason, he is also considered to be the founder of vertebrate paleontology. Cuvier is most famous for his "law of correlation of parts," wherein he discovered that certain types of anatomical features tend to be associated. If you are a flesh eater, you will have sharp teeth and claws; if you are a plant eater, you will have flat grinding teeth and hooves; and so on. Using this law, paleontologists have been able to reconstruct whole animals from just a few key bones because the other parts of the anatomy are so predictable.

Excerpted from The Story of the Mammals in 25 Discoveries: Amazing Fossils and the People Who Found Them by Donald R. Prothero. Copyright (c) 2026 Donald R. Prothero. Used by arrangement with the Publisher. All rights reserved.

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Could a psychedelic drug help the brain recover from mild injuries? New research suggests that psilocybin, the mind-bending ingredient in magic mushrooms, might protect the brain from the damage caused by minor head impacts.

Even mild head impacts that don't count as concussions can raise the risk of neurodegenerative disorders such as chronic traumatic encephalopathy (CTE), so finding an effective treatment for these blows could be useful for warding off debilitating conditions down the line.

The new research, published in the journal Communications Biology, included only lab rats, so there's more work to be done to translate the findings to humans. But the early results hint at a new application for psilocybin — a drug that's already been explored for a range of other conditions, including depression, PTSD and anorexia.

Live Science spoke with study co-author Argel Aguilar-Valles, an associate professor of neuroscience at Carleton University in Ontario, about the new study and how the research might eventually translate to treatments for repetitive head injuries.

Nicoletta Lanese: In this new study you focus on mild head trauma. Why does that minor level of injury still raise concern?

Argel Aguilar-Valles: This work was spearheaded by our collaborator, Dr. Craig Ferris at Northeastern University in Boston. The idea was to focus on the cumulative effect of those milder head hits, or injuries, that happen quite commonly; a lot of children and older adults can have repeated instances of these events of head trauma, and it doesn't necessarily lead to any immediate treatment or hospitalizations because they are considered fairly mild.

But over time, there's evidence that this can lead to cumulative and long-term effects that can affect the health outcomes of these individuals, particularly as we age. It's a risk factor for several forms of dementia. So the idea was to try to model this with a milder version of head injury [in lab rats].

So it's repeated — it's three hits — they're controlled, they're fairly mild. And they produce some alterations in the brain networks that are evident in using either MRI [which looks at the brain's structure] or functional MRI [which analyzes brain activity] analysis.

NL: So these are head impacts that don't come with the symptoms associated with concussions?

AAV: It's always difficult to compare [what a rat is experiencing] to what a human might experience, especially here. One good way to put it is that there's no loss of consciousness ‪—‬ so in those instances where the hits happen but you don't black out.

NL: Is there anything available now to manage and treat these mild impacts?

AAV: Well, as far as I'm aware, there's not really an intervention. I've experienced this secondhand with my children. Sometimes, they will come back from school and then they [the teachers] say, "OK, they had a hit on the head; there's a bump, but they didn't lose consciousness or anything."

Then sometimes, you go to the doctor concerned and typically you're told, "OK, just keep them under observation." If there's no vomiting, nausea, if there was no loss of consciousness, typically they just send you home and say keep an eye. Put some ice on it. Maybe don't overexert yourself in the next few days — and that's about it.

There is no intervention — for instance, if we do this [treatment], it's going to prevent you from developing dementia 50 years down the line. There's obviously nothing like that, particularly when you have repeated instances and the effects are cumulative.

NL: What made psilocybin seem like a potentially promising treatment for head trauma?

AAV: My group specifically has had an interest in testing the ability of molecules collectively known as psychoplastogens. We didn't coin the term, but it basically refers to all of these drugs that produce these brain-plasticity effects [changes in the brain's structure and activity]. These include serotonergic psychedelics [such as psilocybin and LSD, which affect serotonin receptors], and also things like ketamine or even MDMA.

We observe changes in cultured neurons in response to these drugs, in terms of dendritic complexity and increased synaptic spine density [changes in neurons' incoming and outgoing wires]. And in vivo [in live animals], you also observe functional reorganization of networks. All of these drugs have the ability to trigger these mechanisms. They do it through different pharmacological targets, but they all converge on some of these plasticity effects.

There are deficits in this plasticity in psychiatric illnesses, but also, obviously, in neurological disorders and even neurodegenerative disorders, where these plasticity mechanisms are completely nonfunctional.

So, we wanted to test the limit of the ability of these molecules to rescue, or to provide some therapeutic relief, in conditions where you have physical damage or neurodegenerative pathological mechanisms underlying the disorders. We observed — and not only us, but several other labs have also observed — that some of these molecules do seem to provide some level of therapeutic relief. [Editor's note: The current study looked only at physical trauma, but other labs have started to explore psilocybin for neurodegenerative disorders.]

It's still unclear if they're disease-modifying, in the sense they could provide lasting changes that can modify the course of the disorder. But so far, the evidence indicates that they can at least help to ameliorate some of the negative consequences of either neurodegeneration models or physical trauma, like in this case.

NL: Psychedelics have been more thoroughly studied for conditions like depression. In both depression and head trauma, could similar mechanisms explain the drug's potential benefits?

AAV: Some of the cellular effects might be similar. But the underlying condition can look quite different. Even if you think of two cases of depression, they can look very, very different. The drugs are going to be engaging similar mechanisms, but also the context in which these mechanisms are occurring will probably affect the outcome. What is remarkable about these drugs is that they seem to be working in both cases, so they're certainly tackling something that might be common in both situations.

We don't know the limits of these drugs yet. I'm not trying to imply that they don't have limits; what I'm trying to say is that our knowledge is incomplete. We don't know when they will work better than other potential treatment options.

I feel that will come when their clinical use is more widespread and we have a better idea of how they work in the heterogeneous populations that clinicians have in real life. In our animal models, conditions are very, very controlled and homogeneous, so they respond in a certain, similar way, whereas in the clinic, you observe huge disparity [in responses].

NL: Is there reason to think that psilocybin would be more promising than other psychoplastogens?

AAV: I think a lot of the focus on psilocybin has been because it's one of the psychedelics that's been more widely tested both in clinic and preclinical settings.

I'm not a clinician, but one of the reasons why psilocybin is favored over others is the length of the psychedelic trip. It's a few hours. If you go with something like LSD, it will last much longer. While the person is under the influence of the drug and undergoing the trip, there needs to be clinical supervision, so it becomes really challenging logistically to arrange sessions with psychedelics that last a long time.

That's also motivated preclinical research, like ours, to focus on this drug, as opposed to others that may have similar effects. From a potential translational perspective, it might be a safer bet to study this drug.

NL: In clinical trials of psychedelics, scientists often use a very small dose to try to avoid triggering strong hallucinogenic effects. Was that a goal with the rats?

AAV: No, they're probably experiencing something — this is a relatively high dose. A lot of people use 1 milligram of psilocybin per kilogram of body weight. In this case, they were using 3 milligram per kilogram, and it was based on previous imaging studies where they looked at the effects of this drug.

One measure we use is the "head twitch response," which is a behavioral measure that we commonly use in rodent work to test the hallucinogenic potential of a drug. This is a very rapid head movement that occurs in response to the serotonergic psychedelics. It's a behavioral response that correlates with hallucinogenic potential, and not perfectly.

For psilocybin, it's been very well characterized in the sense that it's mediated by the serotonin 5-HT2A receptor [in rodents], which is the same receptor that mediates hallucinations and the psychedelic trip in humans.

NL: What notable changes did you see in the rats in this study?

AAV: The measurements were done nearly three weeks after the injury. It's relatively short if you think of a human, but for a mouse, things happen much faster metabolically and physiologically. There was at least evidence of increased phosphorylation of tau [changes in a specific brain protein tied to Alzheimer's], and that was reversed by the treatment with psilocybin. That was certainly one surprising finding, and it's worth following up, I believe.

But also the hyperconnectivity — the brain's functional connectivity was really dramatically affected in the treated rodents with the head hits. They not only recovered but went to higher levels than the control-group animals.

We don't really know what the meaning of that is, but certainly it's quite remarkable how the networks became hyperconnected. And hopefully that means something positive for the animals. But it was certainly surprising, the level of recovery of that particular measure.

NL: And these effects were seen throughout the brain?

AAV: There were effects in a lot of brain regions — the thalamus, the hippocampus, the basal ganglia, and all different parts of the cortex, etc. One of the things that stands out from this study was the connectivity of dopaminergic nuclei [hubs of dopamine production in the middle of the brain]. Their connectivity is really fundamentally changed by the hits and then by the treatment with psilocybin.

These modulatory regions, the dopaminergic regions, are concentrated in one part of the brain, but they affect overall brain function because they have these widespread connections. So they're really crucial for a lot of functions, and we're seeing effects in these regions — that's really intriguing.

NL: Is it known whether the strength of the psychedelic trip has anything to do with the degree of benefit?

AAV: It is currently a hotly debated topic in the psychedelic field, whether the intensity of the psychedelic experience has anything to do with the beneficial effects or not. You can envision situations like psychological trauma, as opposed to physical trauma, where that trip might be part of the therapeutic mechanisms. It becomes evident in the debriefing sessions after psychedelic treatment, where it seems like in some cases, the psychedelic experience is fundamental.

But these are fairly correlative measures — if the two happen at the same time, it doesn't mean that they are linked together causally. So that's something that is being tested actively. One of the ways is the development of these non-hallucinogenic analogues that seemingly trigger similar plasticity mechanisms as their psychedelic counterparts do [without causing a trip].

I don't think we've had the first clinical trial with these drugs yet. Some of them may have undergone Phase I clinical trials just for safety, but I believe none of them have been tested in Phase II trials yet [in which their effectiveness is explored for specific conditions].

NL: Given this work is in rats, what are the next steps to translate this into a treatment for people?

AAV: Extending the observations, like other groups have done — looking at what happens if you do give this treatment months after the events. It's still unclear to me if, with this model we have, you will have effects months later.

We have some correlative measures that potentially BDNF expression [a gene for brain-derived neurotrophic factor, which helps neurons grow connections] is increased, and also the levels of its receptor, called TrkB. That is a possibility that needs to be further investigated, trying to find out whether these neurotrophic factors are crucial for the effects that we're seeing.

And obviously, the psychedelic trip is still a potential issue. But testing whether these non-hallucinogenic derivatives have the same lasting effects as their hallucinogenic counterparts do — that will be crucial and that can, in some cases, potentially facilitate the translation [into treatments]. Because not every person reacts the same way to these hallucinogenic compounds, and not everybody has the same risks.

NL: I assume the non-psychedelic options might be better for children, for instance?

AAV: We don't know what the consequences [of psychedelic use] are in a developing brain. There's not enough data. That will be obviously a big thing to sort out before recommending the use of these drugs, and maybe some of those non-hallucinogenic derivatives may hold the answer for that — for those cases where you really don't want to induce a full-on psychedelic experience.

There's also schizophrenia and a bunch of other psychiatric diagnoses with psychosis associated with them — from bipolar or psychosis-like events or episodes — where you might not want to apply a serotonergic psychedelic.

NL: Looking ahead to the next five to 10 years, what do you hope to see in the field?

AAV: There's a lot of enthusiasm in the field and a lot of push to try to characterize and understand better these drugs, from a basic perspective or a cellular level up to a brain wave level and then also the psychological effects. So there are a lot of different disciplines implicated in studying these drugs, and I think that's really exciting. That will hopefully lead to a wealth of knowledge about these drugs — not only their effects but also their limitations and their potential risks.

Hopefully we will have a balanced approach as scientists, to be able to really tease apart in which cases it [psychedelic treatment] will be really useful and in which cases the risks outweigh the benefits. That will be crucial to understand.

There's a lot of potential there, but we should proceed with caution.

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

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Among the many risks astronauts face during long-haul spaceflight, an extended stay in microgravity is one of the most consequential for long-term health, with effects on vision, bones, muscles and many other aspects of the body.

One solution might be artificial gravity —‬ some way to create forces similar to Earth's gravity on a spaceship, akin to the giant rotating ring from Stanley Kubrick's 1968 film "2001: A Space Odyssey."

But is that technology ever coming, or will it remain science fiction?

"There's really no reason it couldn't happen," Torin Clark, an associate professor of aerospace engineering at the University of Colorado Boulder, told Live Science. "From a technical perspective, this is something that could happen in the very near future."

In fact, artificial gravity has almost made its way to space before. The Centrifuge Accommodation Module was a planned 8.2-foot-wide (2.5 meters) centrifuge for the International Space Station (ISS), but the project was canceled in 2005 for budgetary reasons.

"[Artificial gravity] is one of those things ‪—‬ like all of a sudden, it's super popular, and then all of the scientists at NASA and everybody … have a lot of funding to understand how to actually implement this, and then it just dies," Ana Diaz Artiles, an associate professor of aerospace engineering at Texas A&M University, told Live Science. "And then it comes back, and dies, and comes back. I've been going through a couple of these cycles in the time that I've been doing this."

Besides budgetary concerns, there are questions about how such a solution would be implemented.

"Everybody agrees it's a good thing to do. The problem is that we don't know how to implement it," Diaz Artiles said. "How much gravity do you need? How big does [the device] have to be? How long do you need it to be? And how long do you have to use this? Should we use continuous gravity or a short-radius centrifuge, something where you go in and out?"

Researchers have three main approaches for creating artificial gravity. One is the classic sci-fi idea: a giant ring that rotates passengers' entire living quarters so they live and work under forces similar to Earth's gravity.

"You have a relatively long radius, which means you don't have to spin very fast to create gravity," Diaz Artiles said. "But this is massive. You can't get all the parts up there in the same spacecraft — you need multiple spacecraft and to assemble everything. So, of course, you can see what a big endeavor this is."

A short-radius centrifuge is a more feasible option. It's essentially a tube with a radius of 6 to 10 feet (1.8 to 3 m) that spins to simulate gravity. A passenger sits or stands inside, with their head closest to the center of rotation, so the spin generates the strongest pull down toward their feet.

Instead of allowing passengers to live in artificial gravity, this smaller device would be used in short daily sessions. "It's kind of like an exercise device," Diaz Artiles said. "In the ISS, you have a treadmill, you have this resistive exercise machine, so you go there for 30 minutes to do your exercise, and then you get out."

The final option is for spacecraft to create gravity via linear acceleration. This works in the same way that an accelerating car pushes passengers back into their seats, except the spacecraft would be oriented to push an astronaut's feet into the floor. To slow down, the spacecraft would turn around, firing its thrusters in the opposite direction to decelerate smoothly while maintaining a roughly similar gravity for its occupants.

"But then you need something like an engine that is able to accelerate all the time," Diaz Artiles said. "And propulsion-wise, I think we're not there yet."

Although a short-radius centrifuge is the most feasible approach in terms of both cost and engineering, it does have some drawbacks. For one, its fast spin can induce the Coriolis cross-coupled illusion ‪—‬ a sensation of tilting or tumbling that happens when you tilt your head off-axis while rotating.

This is the effect that causes motion sickness, Clark said.

However, Clark and his team have found that people can build a tolerance to the sensation with training, simply by being in a slowly spinning centrifuge and gradually increasing the speed when they no longer feel the sensation.

"If you very slowly, incrementally increase the spin rate … and do that not just over one session but over multiple sessions across multiple days, as far as we could tell, anyone can be made to incrementally acclimate to the rotating environment [of] up to 20 to 30 rotations per minute," Clark said.

Would artificial gravity prevent harmful effects on the body?

But researchers still don't know how fast the centrifuge would need to rotate, or how long someone needs to spend inside it, to benefit. Long periods in microgravity can lead to bone and muscle loss, loss of aerobic fitness, blood clots, and visual issues from fluid shifts in the eyes. The hope is that artificial gravity could prevent those effects, but exactly how much gravity is necessary remains an open question.

Studies of people on head-down tilt bed rest ‪—‬ the standard research method for simulating spaceflight deconditioning ‪—‬ have found that 30 minutes a day in a centrifuge did prevent some loss of muscle function.

"Thirty minutes a day … maybe is not enough," Clark said. "Maybe an hour or even two hours a day, and maybe at higher G levels, would be beneficial."

But these studies are expensive and time-consuming. "It's very difficult," Diaz Artiles said. "I think people are interested in this concept, but we just don't have a good answer."

In the end, it's not a technological challenge that's keeping artificial gravity from being used in space; it's knowing the best way to employ it and securing the budget for it.

"We know how to do this. As humans, we have done more difficult things," Diaz Artiles said. "We need the money, but we also need to better understand the need."

See how much you know about human exploration into space with our spaceflight quiz!

Cape Cod is known for its lobsters and its growing great white shark population, but now the holiday hotspot has another extraordinary animal to showcase: A rare two-headed diamondback terrapin that is surviving against the odds.

The baby turtle, which weighed just 0.18 ounces (5.2 grams), was brought to the Cape Wildlife Center in Barnstable, Massachusetts, on Sept. 17, according to a Facebook post from the wildlife center. It was originally found by representatives of the Mass Audubon Wellfleet Bay Wildlife Sanctuary at a protected nesting site in the town of Wellfleet.

The turtle's condition, known as bicephaly, is a rare developmental disorder that's typically caused by the incomplete splitting of a single embryo during the formation of identical twins. It results in conjoined twins that share one body but have two fully formed, independent heads.

Zak Mertz, CEO of New England Wildlife Centers, which includes the Cape Wildlife Center, said the recently discovered diamondback terrapin (Malaclemys terrapin) is an uncommon example of bicephaly in turtles. Both genetics and epigenetics ‪—‬ the study of how genes and environment can interact ‪—‬ are thought to play a role in the condition's development.

"Our understanding based on the available research is that bicephaly is caused by both genetic and epigenetic factors," Mertz told Live Science in an email.

"It may have to do with the relatively long lifespan of the turtles, their preference for returning to the same nesting sites, and a limited gene pool due to their conservation status," he said."It may also be influenced by environmental factors, such as the temperature, humidity during incubation, physical characteristics of the nesting sites, or potentially even things the parents are exposed to in the environment."

Having two heads is rare but not unprecedented. According to the center, this is the third bicephalic terrapin found in the area in the past five years, providing another opportunity to learn more about the animals. Other wild animals with bicephaly have been found in recent years, including a two-headed porpoise found off the coast of the Netherlands and a two-headed dolphin that was found on a Turkish beach.

A 2021 study found that rare two-headed and partially duplicated sea turtle embryos and hatchlings showed significant craniofacial and spinal abnormalities and were generally smaller than typical hatchlings. The research found bicephalic turtles faced survival challenges because their abnormal anatomy could impair coordinated movement, feeding, and other functions essential for survival, highlighting the importance of monitoring such deformities as potential indicators of population and environmental health.

Diamondback terrapins are found in brackish marshlands along the Atlantic and Gulf coasts of the United States. Brackish waters have more salt than fresh water but less salt than seawater, and often occur where the freshwater of a lake or river meets the salty sea. These terrapins are classified as threatened by the Massachusetts Endangered Species Act, and their broader conservation status at the federal level is currently under review.

Veterinarians are monitoring the rare terrapin's health closely. "It is fascinating and an area that certainly merits more study," Mertz said. "We are excited to care for these two and learn as much as we can to inform future study in the process."

This year's exceptionally strong El Niño has brought a rare gift to Chile's Atacama Desert: rain. In one of the driest places on Earth, that rare moisture has awakened millions of seeds and bulbs that can remain dormant underground for years, transforming the landscape into a spectacular carpet of color.

Known locally as "desierto florido," or "flowering desert," the phenomenon is one of nature's most remarkable transformations. Patches of purple, pink, white, red and yellow now spread across hillsides and plains that for much of the year appear almost completely lifeless.

"It is a unique phenomenon; there are more than 200 plant species," Jorge Carabantes, head of the Protected Areas Department at the National Forest Corp. (CONAF) in Chile, told The Associated Press. "This is a flowering event that is obviously extraordinary and unusual, very different from other blooms that occur elsewhere on the globe."

Typically, the Atacama gets just 0.6 inches (15 mm) of rain a year. But thanks to the super El Niño, record levels of rain fell between July and August in several Chilean regions, including levels not seen since the 1950s, with some areas receiving more than 7 inches (190 millimeters), Carabantes told the AP.

While this unprecedented precipitation has caused flooding in some areas of Chile, it's created a 6,560-square-mile (17,000 square kilometers) swath of flowering blooms across the Atacama Desert. This is the most extensive desert bloom since 1997, CONAF representatives told the AP.

For photographers and tourists, the landscape is breathtaking, with bright colors contrasted against the dark Atacama mountains and Chile's cloudless skies. But the bloom is fleeting; by the end of the Southern Hemisphere's spring, many of the flowers will disappear, leaving behind seeds and bulbs waiting for the next extraordinary rains.

Here are five photos from Getty Images photographer Javier Torres that showcase the beauty of this rare event.

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The first animals may have appeared on Earth hundreds of millions years earlier than their fossils suggest, a new modeling study suggests.

Previously, the earliest fossil evidence of animals dated to around 574 million years ago, during the Ediacaran period (635 million to 538 million years ago). In the new paper, a research team argues that we can't just rely on the spotty fossil record, and suggests that animals first appeared up to 200 million years earlier than the oldest known animal fossils.

In the study, published Friday (Oct. 2) in the journal Science Advances, the researchers argue that the absence of animal fossils in some exceptionally well-preserved ancient rocks doesn't mean the animals were absent from history. Instead, they suggest that the fossil record may be missing a key chapter of animal evolution, potentially pushing the origins of animals back to between 800 million and 700 million years ago.

This would place the emergence of animals deep within the Neoproterozoic era (1 billion to 539 million years ago), possibly before or during some of Earth's most extreme ice ages.

Even though scientists haven't found undisputed animal fossils from the Neoproterozoic, that doesn't mean animals didn't live at that time. Fossils can be absent from rocks for several reasons, including because scientists are looking in the wrong places or the conditions were unsuitable for creating fossils, making it difficult to determine the earliest evolved animals.

"Until that evidence becomes available, the precise birth date of the animal kingdom remains uncertain," study co-author Ross Anderson, an associate professor of natural history at the University of Oxford, said in a statement.

Where are the animals?

Until now, most researchers relied on the well-preserved rocks from the Ediacaran period, including the roughly 590 million-year-old Weng'an Biota in China, to investigate the timing of animal evolution. Because rock deposits there contain uniquely preserved microscopic organisms but no definitive animal fossils, experts have sometimes treated them as a kind of upper limit for when animals could have evolved.

"So the game is basically how much does it predate our first fossil discovery by and what happened in that evolutionary black box between when they actually originated versus when we get our first fossil window," Karma Nanglu, an assistant professor of evolutionary paleobiology at the University of California, Riverside who wasn't involved with the study, told Live Science.

But the researchers wondered whether other fossil sites from known animal periods actually had evidence of animal fossils.

To find out, Anderson and his colleagues studied more than 140 samples from the Kheseen Biota in Mongolia, which is more than 40 million years younger than the 590 million-year-old Weng'an Biota deposit. Given that it's a younger deposit, the researchers hypothesized that there should be evidence of animal life left in the rock. Using electron scanning microscopy, the researchers saw microscopic fossils preserved in extraordinary detail, including tiny, spherical organisms and embryo-like structures containing internal cells.

Yet, despite the quality of preservation, the researchers couldn't identify any of the microfossils as animals. That's important, because by the time the Kheseen Biota was deposited, animals were present elsewhere on Earth.

"The Kheseen Biota breaks the argument that the exceptional microfossils of Weng'an mean we would have seen animal fossils in the assemblage had they existed at the time," Anderson said. "The Kheseen microfossils are just as well-preserved, yet animals continue to be absent — despite the fact we know at that point they existed."

Using molecular clocks

Given the absence of fossil evidence, Anderson and his collaborators turned to another common method used to date ancient life: molecular clocks. Molecular clocks estimate when evolutionary lineages diverged by comparing genetic differences among living organisms and combining those differences with rates of genetic change. For example, if two bird species have five DNA changes and one DNA change takes about 1 million years to accumulate, scientists could estimate that the two species diverged around 5 million years ago.

"Molecular clocks are useful when we don't have a particularly good fossil record for a group of interest or a time period of interest," Nanglu said.

When the analysis was constrained by the younger Weng'an deposit, the estimated origin of animals was comparatively recent. When they used older geological constraints — specifically rock formations in Norway, Australia and Arizona deposited between around 850 million and 730 million years ago that have been used in the past for trying to find animals' early ancestors, the timeline changed. By comparing modern animal DNA to reference dates from the fossil record along with evolutionary rates of change — their estimate shifted back by roughly 200 million years, to between about 800 million and 700 million years ago.

"Pre-Ediacaran animal body fossils still elude us, and this analysis does not prove that animals existed 800 million years ago," study first author Orin Lole Durbin, a doctoral student of paleobiology at Virginia Tech who was a University of Oxford undergraduate at the time of the study, said in the statement. "Meanwhile, our molecular-clock analyses show how much further back their evolutionary history could extend."

Could animals have lived before "Snowball Earth"?

There are other clues that animals may have a longer history.

Chemical fossils, or biomarkers, have been interpreted as evidence consistent with sponges living at least 650 million years ago, tens of millions of years prior to the oldest known animal fossils.

If animals did originate 800 million years ago, their emergence would also intersect with the Cryogenian period, which began around 720 million years ago as part of the Neoproterozoic era. During this interval, Earth experienced enormous glaciations often referred to as "Snowball Earth."

Although there is no definitive answer to whether animals survived this uncertain time, the researchers plan to search additional Neoproterozoic rocks with different environments and preservation conditions to find more evidence for their analysis.

"Fossils themselves are by definition kind of hidden from general sight," Nanglu said."Beyond that there's an even more hidden world, and that has a lot of potential to tell us about animal origins."

Think you know about natural selection? Try your hand at our evolution quiz!

This year's "super" El Nino means the U.S. will likely face a higher risk of stormy weather and flooding, so experts are recommending Americans stock up on food.

And flooding is just one of the natural disasters people will face — many people are at risk of wildfires, power outages or earthquakes. While some disasters are unexpected, preparation can make a significant difference in how much they impact peoples' daily lives.

But is anyone actually prepared for the worst?

Levels of preparedness vary widely. Some may keep an emergency kit stocked with food, water and first-aid supplies, while others may have an evacuation plan, emergency contacts or designated meeting place for their household. And others do nothing at all. Although a recent study revealed there's no single place on Earth that's best prepared for global disaster, there are steps people can take to feel well equipped.

Experts recommend stocking up on food supplies and other essentials, especially in areas that might be more disaster prone. But how prepared are you? Answer our poll below, and share how you've prepared for emergencies or what you have in your disaster kit in the comments.

Archaeologists have been arguing for more than a century about whether people first entered the American continents before, during or after the coldest peak of the last ice age, called the Last Glacial Maximum (LGM). Now, a new study of the available genetic evidence suggests the group that gave rise to today's Indigenous people migrated to the Americas no earlier than 21,000 years ago.

"The evidence points to the arrival of humans ancestral to contemporary Indigenous peoples likely near the end of the Last Glacial Maximum, but earlier migrations may also have occurred," study co-authors Bethany Potter, an archaeologist at the Kansas Geological Survey, and Savannah Hay, a biological anthropologist at the University of Kansas, told Live Science in an email.

In a study published online Sept. 23 in the journal Current Opinion in Genetics & Development, the researchers used genetic evidence to investigate the three main archaeological models for Native American origins: an entry into the Americas before the LGM more than 25,000 years ago, entry during the LGM some time between 25,000 and 14,000 years ago, and entry after the LGM more recently than 14,000 years ago, sometimes called the Clovis First theory.

"The reason this topic is so contentious among anthropologists is because not all archaeologists agree about which of the earliest sites are legitimate, and that influences which model they think is most accurate," Potter and Hay said. "We know that humans were definitely in the Americas by about 13,500 years ago. We still don't know if they arrived earlier than that and, if so, how much earlier."

Genetic evidence of the first people in the Americas is scarce. The first whole genome from an ancient Indigenous person, who lived around 4,000 years ago in Greenland, was sequenced in 2010. Since then, the researchers wrote in the study, scientists have published around 250 whole genomes, along with genome-wide data from around 1,200 ancient Indigenous people.

These DNA studies have revealed key information about the first people in the Americas. During the LGM, around 25,000 years ago, a group of people living somewhere near Siberia or Beringia, which included the land bridge connecting Asia to Alaska, split into different groups ‪—‬ ancient Native Americans, ancient Beringians and one or more "ghost" lineages ‪—‬ and moved quickly along the Pacific coast, possibly splitting again around 16,000 years ago into Northern Native Americans and Southern Native Americans.

"Huge gaps in our genetic dataset"

Although the current genetic data lines up with archaeological evidence of people entering the American continents at least 14,000 years ago and perhaps as far back as 21,000 years ago, more DNA evidence is needed to fully understand how and when the first Indigenous people arrived from Siberia.

"There are huge gaps in our genetic dataset," Potter and Hay said. "For example, there are still no published ancient genomes from the Great Plains, despite that being where our lab group is situated." And these gaps could be hiding evidence of earlier migrations.

Human footprints found at White Sands, an archaeological site in New Mexico, have been dated to 23,000 years ago. If this date is correct, it implies that people were living there prior to the LGM. The Acoma Pueblo people living in the region of White Sands today recognize these footprints as traces of their ancestors, Potter and Hay said.

But genetic data from contemporary and ancient Indigenous peoples in the Americas currently shows that the White Sands population did not make a significant genetic contribution to the ancestors of today's Indigenous people, the researchers said. "However, it is possible we have not sampled their descendants' lineage, or that they contributed a low proportion of genetic ancestry to ancient North American populations," they said. "Perhaps we've just not found DNA from the White Sands population yet."

There are several scenarios compatible with a pre-LGM entry of people into the Americas, the researchers wrote, but assessing those models also requires more genetic data. To date, the earliest sampled genome is from a 12,800-year-old individual known as the Anzick-1 child, whose bones were found in Montana. Extrapolation from the DNA of the Anzick child and other early ancestors points to an initial migration that occurred no earlier than 21,000 years ago, Potter and Hay said.

"Expanding geographic coverage in general would be hugely beneficial, but many of us are intentionally slow with our ancient DNA approaches to ensure research relevant to descendant communities is ethical and collaborative," Potter and Hay said.

It is unclear when or if the longstanding question of when people first entered the Americas will be resolved, as current archaeological and genetic evidence do not unequivocally point to a single answer, Potter and Hay said, but "the publication of new ancient genomic data from the Americas is powerful, as it has the potential to fill in these gaps and reframe how we see these early peopling events."

How much do you know about the first people to reach the Americas? Find out with our First Americans quiz!

An engineer has utilized AI to break a previously unsolved cipher used by Napoleon Bonaparte to send secret messages to his generals — enabling us to read a 217-year-old letter for the first time. The announcement has historians excited about AI's potential to become a modern-day "Rosetta Stone" for translating coded historical messages.

Carter Church, an AI engineer at cybersecurity firm Sentinel One, laid out the findings in a post on X on Wednesday (Sept. 30), explaining how he gave OpenAI's new model GPT-6 Astra one prompt and one image to crack the centuries-old code. Six hours later, the task was complete.

"I didn't believe it at first," Church told Live Science in a message. "Everyone has the experience of seeing a model claim something outrageous, but the difference here though is that the solution is mechanically testable: there's essentially zero chance an incorrect key could produce coherent and historically consistent output."

The letter was sent in 1809 on Napoleon's request by his stepson Eugène, the viceroy of Italy, to Marshal Auguste de Marmont, who was stationed far from any other French troops on the eastern shore of the Adriatic Sea. The letter's purpose was to tell Marmont the position of every other French and allied army across the continent. However, to avoid revealing military secrets to France's enemies should the letter be intercepted, the message was written in code.

Church found the letter after searching for an appropriate code to break to demonstrate GPT-6 Astra's capabilities. "The verifiability of solutions is actually the most difficult part, far more difficult than generating potential solutions," Church said. "You simply cannot automate accountability."

According to Church, the only publicly available image of the letter was a low-resolution scan published in a French army journal in 1969. It contains 155 different signs — 1,300 signs in total — and the code is homophonic, meaning common letters have several interchangeable symbols.

But this low resolution scan and a single prompt was all GPT-6 Astra needed to transcribe the text and find a partial table by cryptology historian Daniel Tant — previously unlinked to this letter — that documented what 33 of the symbols meant, accounting for about a third of the letter.

"Astra made this connection itself via web research as it was investigating," Church said. "As I understand it: Tant catalogued the table as 'Code entre Eugène de Beauharnais et le Général Grammont' which may have been a naming mistake (Grammont vs Marmont?). Either way, Astra identified this example and just decided to try and apply it to this cipher...and it worked!"

GPT-6 successfully used the partial table to determine what each of the other symbols stood for and translate the message.

"This is a really interesting use of Artificial Intelligence, and it's refreshing to see AI being used productively to try and provide a credible solution to a historical mystery," Zack White, a history research fellow at the University of Portsmouth and host of the Napoleonic Wars Podcast, told Live Science in an email.

Michael Rowe, a researcher in European history at King's College London, added that the findings were "impressive" and that because we have access to Napoleon's original correspondence to his stepson, where he detailed what the ciphered message should include, we can be fairly confident in the translation of Eugène's letter.

"It's a bit like a kind of Rosetta Stone," Rowe told Live Science. "If you've tested out AI on this letter, where you pretty much know what the contents would have been because it's referred to in another letter, the AI does its thing and essentially reproduces what you're expecting to see. Then if you use the exact same kind of tool and methodology on something where you don't know [the contents], you're more likely to trust the outcome."

This does also mean that the translation of Eugène's secret message isn't too surprising to historians. "The cipher version just repeated a large segment of what's in that [original] letter, so in a sense it doesn't tell us anything new — it's not like it reveals some kind of great new information," Rowe said.

In addition to the positions of troops and their commanders, Eugène's message encourages Marmont not to fear opposition: "When you receive the order to march, you must not allow yourself to be intimidated by a few troops or a gathering of rabble," the newly-translated letter reads.

According to White, the translation does raise "some curious questions about Napoleon's mindset in the run up to the campaign in Austria in 1809." For example, he said that Napoleon actually had 60,000 fewer troops available to fight at the time than is claimed in this letter, and he also seems fixated on the number of troops Austria might send to invade Italy.

"It's important that historians now set the AI's works in a bigger picture of the history of the period," White said, adding "it will also be interesting to see if the key that has resulted from this AI's work can now be used on other correspondence."

Cracking codes in time

Ciphers were fairly common during this period, conveying sensitive military and diplomatic information.

"French Emperor Napoleon Bonaparte was forced to use ciphers as a way of communicating sensitive information securely across his vast empire," White said. "It was always a very real possibility that these letters would be intercepted, potentially providing vital intelligence to France's enemies about the Emperor's plans."

However, using AI to crack these codes could also offer insights into the private lives of historical figures. "[Ciphers] were often also used for private correspondence," Rowe said, for example letters between elite individuals having extramarital affairs.

The technique could also be used by ancient historians, studying documents in languages and scripts that we don't yet fully understand, or written in illegible handwriting.

"Across time frames, this [AI] is opening doors," Rowe said.

For this particular cipher, Church said that the code itself isn't especially difficult. "Cryptographers could have cracked this easily given the time/energy," he said. However, it would require experts across different areas and take a considerable amount of time and effort, he added.

"Every field has an unsolved backlog of niche problems that specialists don't have the bandwidth to tackle," Church said. "The takeaway here is that the people shortening those lists will increasingly be outsiders who were simply curious."

Church's result was confirmed by Satoshi Tomokiyo, a patent engineer and cryptographer who runs a website documenting unsolved historical ciphers called Cryptiana, and the letter is now listed as "solved" on the website.

"This work is totally reliant on all of the research that goes into finding these ciphers, ensuring they're actually unsolved, contextualizing them, etc and I'd love for those folks to get all of the recognition," Church said, referring to Tomokiyo's website. "That's where the real hard work is."

An international team has reconstructed the face of a man who lived in what's now Ecuador more than 3,000 years ago and whose skull featured in one of history's great anthropological debates.

The facial reconstruction is based on the Punin-2 skull, which a farmer discovered in a ravine near the town of Punín in the Chimborazo region of Ecuador's central Andes in the 1970s.

A similar skull, Punin-1, had been found in the same ravine in 1923 during an expedition led by the American Museum of Natural History. Some scientists at that time suggested its physical features were archaic, especially its prominent brow.

As a result, scientists proposed in 1925 that the first Punin skull was evidence of Oceanic ancestry, possibly through ancient contact with people from Australia or the Pacific Islands.

The ancient sediment layer where it was found — and where the Punin-2 skull was also discovered about 50 years later — predated modern humans (Homo sapiens), prompting some to wonder if they came from a now-extinct relative, such as Homo erectus or the Neanderthals.

But later studies challenged these ideas, and the new facial reconstruction indicates the Punin-2 skull belonged to a modern human man with purely Native American ancestry.

Christopher Rynn, an independent forensic craniofacial anthropologist based in the U.K., said there's no question that the Punin-2 skull was an Indigenous American who originally had descended from an ancestral group of North Siberians and East Asians during the last ice age. "Punín-2 resembles an East Asian skull from the front, but not at all from the side," Rynn told Live Science.

Rynn's colleagues in Ecuador shared their access to the skull, and he started working on its reconstruction last year. The Punin-1 skull is now at the American Museum of Natural History in New York City.

Rynn and his colleagues, led by the sculptor Hector Flores Franco from the University of Chimborazo in Ecuador, are raising funds for further investigations, which will include a reconstruction of the Punin-1 skull and attempt an ancient DNA analysis of both. "DNA will tell us the true genetic lineage," Rynn said.

Disputed dating

When the Punin-2 skull was discovered, researchers suggested it might be the same age as fossils of extinct ice age animals found in the ravine, including mastodons and giant sloths, that were dated to the Pleistocene epoch (2.6 million to 11,700 years ago). Similar claims were made about the Punin-1 skull.

But geological studies of the ravine have since disproved this idea, suggesting instead that erosion and soil movements had mixed the much younger human remains with the Pleistocene fossils.

Rather, it appears the Punin-2 individual lived as a hunter-gatherer in the Chimborazo region between 3,000 and 4,000 years ago. According to recent anthropological and osteological studies, the man was aged about 50 when he died.

Rynn said he had purposefully learned as little about the skull's origin as possible so the face would be based solely on the skull's shape, rather than on his assumptions. But he did follow local guidance about the hairstyle shown on the reconstruction, which was unique to particular tribal groups in the Chimborazo region where the skull was found. The hair is black in color and parted in the middle; real hair will be used in a physical bust of the reconstruction due to be completed in 2027.

"The hairstyle is very specific," Rynn said. "If it's wrong, it looks like a different tribe."

In addition, some of Rynn's early reconstructions made the eyes too protrusive, as they would be in a skull of East Asian origin, so he followed local advice to make them deeper set. The result is a face that looks distinctly Indigenous American. "It explains a lot to me about the broader nature of skull and face shape differences between Native Americans and East Asians," Rynn said.

Faces from the past

Facial reconstructions have been carried out from the remains of hundreds of ancient humans, because archaeologists think these faces provide an important connection to people who might otherwise exist only as old bones.

Rynn has also worked on the reconstruction of a Neanderthal face from about 50,000 years ago. He uses techniques developed at the University of Manchester in the 1970s that are now known as the "Manchester Method," although they are actually a combination of techniques from all around the world, he said.

For the Punin-2 skull reconstruction, Rynn combined digital techniques and partial physical reconstructions with wax to create the face, using libraries of data to determine the right thickness of tissues in particular places.

The digital face has been presented to a select group of people from the Chimborazo region who are likely to be the man's descendants. "It's a portrait of their actual ancestor," Rynn said. "They seem to like it!"

A new AI tool that analyzes speech could give users a glimpse of how they are aging and whether they're at risk of dementia, a new study suggests.

The tool analyzes hundreds of speech and language patterns to estimate the user's chronological age from the way they talk. In a study involving nearly 3,000 Spanish-speaking adults, those whose estimated age was higher than their actual age were more likely to have cognitive problems, dementia and signs of accelerated biological aging, researchers reported Wednesday (Sept. 30) in the journal Science Advances. They were also more likely to have less favorable social and economic circumstances than other study participants.

This voice-analyzing tool is similar to other "aging clocks," which use various biological markers to predict people's risk of age-related diseases.

"Existing aging clocks are very powerful, but many of them rely on brain scans or blood tests that are expensive, invasive or difficult to repeat regularly," said study co-author Adolfo García, director of the Cognitive Neuroscience Center at the University of San Andrés in Argentina. "All of these limitations can be overcome with speech," he argued.

However, the approach still needs to be tested over time and in other languages before it can be used to assess individual patients' risk of dementia, an expert told Live Science.

How the speech clock works

Researchers used data from the ReD-Lat consortium, a large dementia research project in Latin America. The analysis included over 2,900 Spanish-speaking adults from Argentina, Chile, Colombia, Mexico and Peru; their ages ranged from 18 to 88. Of them, about 1,500 were cognitively healthy; the others had mild cognitive impairment (usually marked by mild memory problems and trouble thinking), Alzheimer's disease or frontotemporal dementia.

Each person completed seven tasks, such as describing an animated video; naming as many words, vegetables or animals as possible in 60 seconds; and retelling a short story immediately after hearing it and then again 20 to 30 minutes later. The scientists took recordings, transcribed them, and then identified more than 700 distinct features of the recordings, including pauses, speaking speed, pitch, vocabulary and emotional expression.

They trained a machine-learning model using those features and the participants' chronological ages, teaching it to estimate age from the way a person spoke. The model generated a predicted age for each participant, and researchers compared it with each participant's actual age to calculate what they called a "speech-age gap."

Some people's speech appeared older than expected for their age, the AI tool determined. Cognitively healthy people had the smallest gaps between their true age and the age the AI assigned them, while people with mild cognitive impairment or dementia had larger gaps. The largest gaps were seen in people with language-dominant frontotemporal dementia, which primarily affects communication.

People with older-sounding speech also performed worse on various tests of memory, language and attention, and they had more difficulty with everyday function. Blood tests showed a similar pattern: Larger gaps were associated with greater age acceleration on three epigenetic clocks, which estimate a person's biological age by looking at chemical tags on top of their DNA. These epigenetic markers affect which genes can be switched on and to what degree.

Among people with Alzheimer's disease, larger gaps were also linked to higher levels of p-tau217, a protein associated with the disease.

Larger gaps were also correlated with various risk factors for dementia, such as having financial difficulties, food insecurity, limited healthcare, difficult childhoods or less education. The pattern was similar across all five countries, despite their social and cultural differences, García noted.

What the speech clock cannot tell us yet

The approach is "a huge leap toward making brain health assessments accessible to everyone," said Dr. Manisha Parulekar, co-director of the Center for Memory Loss and Brain Health at Hackensack University Medical Center in New Jersey, who was not involved in the study.

But the speech clock is not a crystal ball. "The human voice is incredibly sensitive to our overall well-being, which means a person's speech could sound 'older' simply because they are severely depressed, exhausted, or navigating serious life stress," Parulekar told Live Science in an email. "As a clinician, I wouldn't use this tool to definitively diagnose someone with dementia in isolation."

Instead, the speech measure could serve as an additional tool that prompts doctors to take a closer look at a patient's cognitive health, she suggested.

In the study, many participants were assessed at a single point in time rather than monitored over a longer period. The researchers therefore could not determine whether an older-sounding voice can predict whether a patient will soon experience cognitive decline, or whether certain voice changes occur as dementia progresses. Plus, the model was trained and tested only in Spanish-speaking participants from five Latin American countries.

"We cannot just take the Spanish model and plug English into it," Parulekar said. The language-specific features would need to be adapted and tested in other populations, she explained.

The researchers now plan to test the approach with other languages and follow people over time to see whether changes in speech can signal future cognitive decline.

"I truly believe that there is a very, very strong signal in speech to anticipate dementia and conversion in the future," García said, "but we need many more diverse studies."

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

Scientists have created the most accurate atomic clock ever made ‪—‬ and it could literally redefine the second.

Researchers recently unveiled the record-breaking device, which uses the vibration of atoms of an element called lutetium to precisely measure each microsecond. It is accurate up to 19 decimal places — a 41% improvement over the previous record holder. The results were published Sept. 23 in the journal Nature.

Atomic clocks have been around since the 1950s. The first atomic clocks were made with the radioactive isotopes of the element cesium, a silvery metal that quickly became the gold standard for timekeeping. The International Bureau of Weights and Measures (BIPM) revised its definition of the second in 1968 to one based on the radiation emitted from cesium-133. Officially, 9.19 billion vibrations of a cesium-133 atom mark one second. (Prior to this, a second was defined as 1/31,556,925 of the length of the solar year 1900.)

Cesium clocks helped standardize the second into something equally useful for both scientific and everyday timekeeping. Since the 1960s, other radioactive metals, including ytterbium and strontium, have been used to make atomic clocks. Today, they are the cornerstone for systems such as GPS, the internet and military technology.

But even modern, ultraprecise atomic clocks have limitations. For example, they are affected by minuscule fluctuations in temperature, magnetic fields and gravity. According to the researchers, the newly developed clock largely sidesteps those issues.

To understand the challenge, imagine precise timekeeping as an ultramarathon and the clock's core elemental isotope as a runner, said study co-author Murray Barrett, a physicist at the National University of Singapore. "Our job is to make sure the runner can go the distance. Lutetium, as it turns out, is a natural born endurance athlete," he told Live Science in an email.

Unlike previous atomic clocks, the team's lutetium-176 clock is not very sensitive to external factors, especially magnetic fields and temperature. Whereas other elements might need environmental temperatures calibrated within a few thousandths of a degree, lutetium-176 keeps ticking even with a 5-degree external temperature swing. Barrett's lab also developed a technique called hyperfine averaging to dull the most important environmental effects, like gravitational fields, leaving very little variation in timekeeping.

Such a sensitive atomic clock could become the International System of Units' – a.k.a., the metric system – new gold standard, the team said. The BIPM is expected to redefine the second in 2030 based on modern atomic clock technology. So far, lutetium seems to be the front-runner for accuracy.

The new atomic clock could also help scientists understand something even more basic about the universe: whether the constants at the foundation of physics, such as G, the gravitational constant, are as constant as we think. "There is some speculation that fundamental constants may actually be changing," Barrett said. "So ultra-precise clocks give us the tools to explore that."

The world's smallest crocodiles use a sneak attack to hunt bats in hellish underground caves filled with poop, a new video reveals.

The footage of the never-before-seen behavior was captured for the upcoming National Geographic series "Africa: Earth's Wild Home" and offers a rare glimpse into the lives of Gabon's mysterious cave-dwelling dwarf crocodiles.

Dwarf crocodiles (Osteolaemus tetraspis), which grow to only around 5 feet (1.5 meters) long, live across West and Central Africa and are typically found in forests, rivers, swamps and similar surface habitats. However, the cave population filmed in the new series is unique.

Discovered in 2008, these subterranean explorers spend their days in total darkness, stalking mounds of bat excrement (guano) in the remote Abanda Caves of Gabon on the west coast of Central Africa. Researchers knew the crocs were feeding on bats and insects, but they weren't sure how because the crocs wouldn't hunt with humans in their lair.

Now, thanks to a team of brave scientists and filmmakers — and special, remote camera equipment — we can watch the crocs catch their prey for the first time.

"I've been working with this population for almost 15 or 16 years now, and that's something we've never been able to see," Matt Shirley, a conservation ecologist and Rolex National Geographic Perpetual Planet Explorer, told Live Science. "No matter how deeply in the bat guano I've been, or how long I've spent in the caves, whenever I'm in there, the crocodiles just aren't doing what they want to be doing."

Gabon's cave crocodiles will be featured in the "Jungle" episode of "Africa: Earth's Wild Home." This seven-part series spans the African continent, covering a variety of wildlife and landscapes, with narration from actress Wunmi Mosaku.

Shirley said the crocodile footage can be used to reconstruct the cave population's behavior patterns and trends.

Researchers aren't sure when the dwarf crocodiles adopted their subterranean lifestyle, but they might have been living in the caves for thousands of years. The cave system is remote and difficult to access, so it's no surprise that the crocs went unnoticed until comparatively recently. Shirley described conditions within the system as intense, with very enclosed spaces, bats and copious amounts of guano to navigate.

"If it's the dry season, you're just kind of standing on this like fluffy mattress cloud of bat guano, but if there's any rain, you're in a bat guano slurry," Shirley said. "Sometimes, to catch the crocodiles, I'm either literally standing with up to my neck in bat guano, or I'm having to lay down to crawl through tunnels and basically move through bat guano slurry, head to toe."

Shirley was part of the team that first documented the crocodiles in 2010. That work led to a 2016 study, published in the African Journal of Ecology, comparing the dwarf crocodiles in the cave to those living aboveground in the forests.

Living in acidic bat guano effectively tans the crocs' grayish skin, eroding it over time to give them a distinct orange color. However, Shirley and his colleagues have found that the cave crocodiles are often better fed than their forest-dwelling counterparts, which the team thinks is likely due to the abundance of prey and lack of predators in the caves.

Currently, the cave population is part of the broader dwarf crocodile species, but it stands out as a genetically isolated group. Shirley noted that the animals have clearly made a choice to occupy the extreme cave environment, despite the potential health risks and noisy neighbors, and are therefore quite possibly dictating their own evolution.

By staying in the cave and mating only with each other, they are accumulating genetic differences that should help them better adapt to their environment, he explained.

"It's very 'Jurassic Park,' you know ‪—‬ life-finds-a-way sort of a scenario," Shirley said. "This is evolution in action."

Dwarf crocodiles are classified as vulnerable to extinction on the International Union for Conservation of Nature's (IUCN) Red List of Threatened Species. However, the IUCN hasn't assessed these crocodiles in decades, so their current conservation status is uncertain.

As a common source of protein for people in parts of West and Central Africa, the species is threatened by overharvesting, as well as by habitat loss, National Geographic reported. However, the dwarf crocodiles also have a very wide range and are particularly abundant in Gabon.

The Abanda Caves, where the subterranean population lives, sit outside Gabon's protected areas, making the cave crocs more vulnerable to any human activities in the area. Shirley noted that the Gabonese government is undergoing a process to protect the caves as a specific reserve.

"I don't think we're worried about extinction of the species, but until that classification of a protected area comes to fruition, the cave population is definitely at risk," he said.

"Africa: Earth's Wild Home" premieres on National Geographic Friday (Oct. 2) at 8 p.m. EDT and will be available to stream on Disney+ and Hulu the following day.

Meriah DeJoseph grew up below the poverty line, so she was intrigued in college when she started reading what researchers had to say about people from low-income backgrounds. But there was something eating away at her. Although well-intentioned, the early research mainly focused on the risks of growing up in poverty.

As she progressed through her education, studying how poverty affects children, she'd go home and describe research in the field to her mom and her friends. The looks on their faces seemed to be saying "Is that really everything? Is that all it says? Is that what you think?"

She realized the research was missing the strengths people she grew up with exhibited, such as creative problem-solving skills and abilities to navigate social hierarchies and read people.

This helped motivate DeJoseph, who is now a developmental psychologist at University of Denver, to try to tell the other side of the story. "I felt like there was more to say about children and family strengths in those contexts that just wasn't being told yet."

Now, along with a handful of other researchers, DeJoseph aims to understand the full spectrum of changes that come with growing up in dangerous, deprived or unpredictable environments.

That is not to say that growing up in poverty is all flowers and roses, DeJoseph stressed. "Growing up in poverty is very hard and does cause a lot of challenges and does increase risk for things that we don't want," she said. But "the other side of it was missing." It's about capturing the full picture, not romanticizing hardship, she added.

Indeed, this balanced perspective does not deny that growing up in adversity — a catchall term that encompasses, for example, neglect, exposure to household or community violence, and household instability — can be damaging or even traumatizing. Rather, the approach acknowledges that individuals raised in such environments may also develop specialized skills that have previously been overlooked or discounted by researchers.

They hope that an understanding of these skills can eventually lead to changes in the educational system that will help narrow achievement gaps between those who grew up facing adversity and those who didn't.

An impoverished view of childhood adversity

Research has repeatedly shown extensive mental health disparities between individuals who faced adversity in childhood and those who do not. For example, children who experience multiple forms of adversity ‪—‬ such as lacking access to basic necessities or enduring aggression or neglect ‪—‬ in early childhood are more likely to be anxious and depressed at age 15. This affects a significant fraction of the population: 16.3% of U.S. children live in poverty, according to a 2022 report by the U.S. Census Bureau, and around 15% experienced neglect or abuse, according to a 2015 estimate.

However, under the prevailing "deficit model" of childhood adversity, experiencing multiple stressors as a young child does nothing but harm brain development. The fact that children from disadvantaged backgrounds score lower, on average, on standardized tests of various cognitive abilities has been used to support this view.

The deficit model is "really stigmatizing and really disrespectful" to people from disadvantaged backgrounds, Bruce Ellis, a professor of psychology and anthropology, heads the Developmental Adaptation, Stress, and Health (DASH) Lab at the University of Utah, told Live Science.

What's more, it "doesn't make any sense from an evolutionary perspective," he said. "Stress should not so much impair development as direct or regulate it towards strategies that are adaptive under stressful conditions."

Even the slightly more hopeful "resilience model," which looks at why some people can overcome adversity to become healthy and successful, focuses on why some people flourish despite experiencing early hardships.

Instead, Ellis and his colleagues have developed what they call an evolutionary developmental perspective. Unlike the resilience or deficit models, both of which frame adversity as solely negative, their framework looks at adversity as a selective pressure that pushes people to develop specialized abilities so they are better equipped to thrive in the environments they grew up in.

"Instead of doing well despite adversity, it's showing a potentially adaptive outcome because of adversity," DeJoseph said.

Humans evolved to be adaptable

From birth, an infant's biology, psychology and behavior are fine-tuned to suit the environment in which they are raised. This adaptability is partly due to genes being switched on differently depending on the environment the individual grows up in during sensitive periods of development, like in early childhood. As a result, people become specialized to their particular setting.

Stress, violence, chaos, hunger and scarcity have been a part of the human experience at many points throughout evolutionary history, so the ability to adapt and thrive when faced with such challenges has likely played a huge role in what it means to be human across time.

In principle, that means that individuals who face adversity early in life are "stress-adapted," meaning they've developed skills and traits that allow them to survive in their harsh and unpredictable settings, such as facing housing instability or living with an abusive caregiver.

In this view, social and cognitive skills that improve the individual's chances of surviving in harsh and unpredictable environments are likely to be more common in people who come from such environments.

The strengths-based approach

But what are these skills? Research has shown a handful of abilities that seem to be enhanced in people who were raised in stressful or chaotic environments. Psychologists initially called these "hidden talents."

Researchers hypothesize that these skills, such as heightened memory for faces and the ability to shift attention quickly, are useful in such environments.

For example, the ability to shift attention quickly may be important when you don't know when or where the next danger could be. "The assumption is, when you're in an unpredictable world where, again, threat can come without warning, where things can change unpredictably, that it's really important to be able to kind of fluidly unstick your attention from one thing and shift to something else, as opposed to being really good at sustaining attention," Ellis said.

In contrast, the ability to focus one's attention on a single task for long periods may be adaptive for someone who can rely on feeling safe; they have learned that they can tune out the outside world without worrying about something bad happening.

Suppressing impulses and resisting temptations based on the promise of future benefits might not be helpful in changeable environments, where rewards are fleeting and may not come around often, DeJoseph said.

Nowadays, to avoid the implication that people who faced childhood adversity have no need of support, researchers tend to call these "stress-adapted skills" rather than "hidden talents," DeJoseph said.

In fact, many of these adaptations that enable children to survive or thrive in stressful or unpredictable settings may still have downsides. For instance, being very attuned to threats may increase your chance of surviving in dangerous environments, but hypervigilance can lead to heightened anxiety in safe environments.

"It might help a child function in one context but create a challenge in another," DeJoseph said.

Uncovering stress-adapted skills

This budding field is "still very broad," and researchers are still mapping out the repertoire of skills that emerge from adversity, DeJoseph said. But a flurry of research has begun to home in on some of those skills.

For example, memory for who has more power in a given situation may be enhanced because understanding who sits where in the social pecking order, including who is more likely to win in a physical fight, is critical for surviving in harsh or dangerous environments. And being quicker to identify patterns in the environment could mean individuals are able to anticipate and spot threats or opportunities in changeable circumstances.

However, it is now clear that some stress-adapted skills require a bit of coaxing to reveal themselves. That's because these skills are specific to the contexts in which they developed, Ellis said, meaning they are more likely to appear in threatening or uncertain situations.

For example, the capacity to update information you are holding in your mind — known as "working memory updating" — is key for tracking incoming information and ensuring it is up-to-date. In a study involving 372 adults, individuals were randomly assigned to read a fake news article that either highlighted economic uncertainty or discussed computer technology. After reading these news clips, the participants completed working-memory-updating tasks.

Participants who reported having more unpredictable childhoods and read about economic uncertainty tended to be better at updating their working memory than children with more stable upbringings. But the results flipped for those who had unpredictable childhoods and read about computer technology. This suggests the ability to detect and quickly process information in a changeable environment can shine in situations that may call for it, the researchers suggested.

Context is key, but so is the content of the testing. For instance, almost all early studies used standardized tests that relied heavily on abstract questions, which may have missed some of the nuances of stress-adapted skills, Tochukwu Nweze, a developmental cognitive psychologist and co-director of the DASH Lab at the University of Utah, told Live Science. Now, some studies are using familiar, real-life stimuli rather than abstract stimuli, like numbers, shapes or colors, he said.

A 2022 study found that teenagers who had been exposed to high levels of violence and poverty in the past scored lower when generic shapes, like squares and triangles, were used, but almost caught up to peers who experienced relatively lower adversity when more relevant shapes, like buses, dollar bills and faces were used.

In fact, a recently published study found that children in the Scampia neighborhood of Naples, Italy — which faces high crime rates, toxic waste pollution, economic marginalization and institutional neglect — showed enhanced working memory and short-term memory compared with kids from a relatively higher socioeconomic neighborhood, but only when the tasks involved remembering faces.

Mixed results and known unknowns

Because this is a young field, mixed results are cropping up everywhere. For example, research on 800 Dutch adults found inconsistent links between current adverse environments and performance on working-memory tasks. Other research from the same team also revealed that exposure to threats in childhood and adulthood was associated with slower information processing across a range of tasks but was not linked with the ability to suppress impulsive actions or quickly shift attention.

These mixed findings highlight the essential need to replicate some of the core findings of the field. No studies in this area have been conducted on older adults, so researchers have no idea how stable these skills are throughout someone's life, Ellis said.

Moreover, as with a lot of other psychological research, the studies into stress-adapted skills have been conducted predominantly in "WEIRD" populations — that is, with people from Western, educated, industrialized, rich and democratic societies. People from non-WEIRD populations have been "grossly understudied," Nweze said, and there must be a concerted effort to correct this imbalance. "There is a need to understand whether there is cultural generalizability of these findings," he said.

In an attempt to do so, Nweze has investigated some of these ideas in his home country of Nigeria. For example, in a 2020 study, he and his colleagues compared 53 children in orphanages or foster homes with 51 children being raised by their biological parents. The team used standard psychological tests to assess these children's abilities to hold information in their mind and suppress impulses.

The children living in orphanages or foster homes performed either just as well as or better than the children living with their biological parents. These results were surprising because they bucked the trend of prior studies finding that institutionalized children were worse at inhibiting their impulses, Nweze said.

Similar results have recently been found in Mozambique, with children from a high-stress community outperforming kids from a relatively lower-stress town on social memory tasks.

What's not clear is how a dangerous, deprived or highly changeable childhood mediates these changes in the brain.

Early life adversity shapes brain development

One researcher who is trying to map out those brain differences is Christopher Monk, a professor of psychology, psychiatry and neuroscience at the University of Michigan.

Monk and his team have found that 15-year-olds who had been exposed to relatively high levels of adversity throughout childhood had different neural connectivity than teens with comparatively low or medium exposure. Adversity in this context included experiences such as exposure to emotional and physical abuse, and to neighborhood and parental violence.

MRI brain scans revealed that kids who had been exposed to cumulatively higher levels of adversity had denser connectivity in the default mode network, which is most active when the brain is not focused on external stimuli, such as during daydreaming. They also had denser connectivity in the frontoparietal network, which is involved in problem-solving and planning.

The salience network ‪—‬ which includes the amygdala, the region involved in processing danger and emotions‪ —‬ was less densely connected.

Although the environment "truly does sculpt the brain," these brain changes are not necessarily good or bad, Monk told Live Science. "They just are what they are. The brain is just always adapting to the environment."

Because it is impossible — and unethical — to randomly allocate children to high- and low-adversity settings, these studies can't show that adversity causes these brain differences. "We're not able to talk about causation," Monk said. "We're talking about one point in time correlating with another point in time."

Also, it's still not clear how differences seen in brain scans translate to stress-adapted skills and abilities. Partly, that's because most neuroscience research has not been focused on these hidden strengths. Instead, it has focused on how childhood adversity harms brain structure and function, often with the goal of explaining the higher incidence of depression, anxiety, impulsiveness and aggression in those who had stressful childhoods.

"New studies could incorporate appropriate measures to specifically test for the neural bases of hidden talents and their development," Ellis and his colleagues wrote in a book on hidden talents.

The $64,000 question

Although some of these stress-adapted skills may emerge when kids navigate changeable, stressful environments, many of these children will wind up leaving those environments later in life. So how can society leverage the skills of stress-adapted people to help them thrive in an environment that may be very different from the one they grew up in?

Although the research is intriguing, experts acknowledged that it isn't robust enough yet to show exactly which skills stress brings out — let alone to inform policy or educational recommendations. "I feel like we need to get the science a bit more solid before it makes sense to put those in real-world settings," DeJoseph said.

But experts agreed that schools are the easiest places to start based on what is already known. The hope is for researchers to work with school curriculum development staff and teaching experts to replace abstract concepts with more meaningful materials. "That's where one policy could potentially have manifestable impacts," Nweze said.

Ellis said the discovery that some skills can be equalized or enhanced when the right materials or contexts are employed could be the answer to "the $64,000 question, or more like the $64 billion question: how do you address the disparity in educational success and career success among people from rich versus poor backgrounds?"

Still, simply moving away from assumptions that individuals from lower socioeconomic backgrounds are "broken" could have a positive impact.

When researchers ran a series of sessions for educators at two U.S. universities in which they described the strengths of kids who had faced economic hardship, they found that educators had more positive beliefs about their more marginalized undergraduate students.

"Perhaps most strikingly, economically marginalized students earned grades that were more than a quarter of a grade point higher, on average, in courses taught by educators who participated in the strength-based learning group compared to those in the control group," the study authors wrote in the paper. This translated to a difference between a C+ and a B-, which was achieved not by changing curriculum but simply helping teachers better understand their students' identities and strengths.

"This perspective change seems so simple," DeJoseph said, "but it seems to have a real impact."

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An artificial intelligence (AI) model's failed attempt to crack one of math's most notorious unsolved problems has helped a human mathematician make progress on a related puzzle.

Earlier this summer, Claude — Anthropic’s AI model — attempted to find a solution to what's widely considered one of the most important unsolved math problems. Known as the Riemann hypothesis, it proposes a hidden order behind the apparently random distribution of prime numbers.

And while the bot's attempt failed, it did make a huge leap in progress on a related problem. Now, Youness Lamzouri, an expert in this field at the University of Lorraine in France, has not only confirmed Claude's progress using a different and more intuitive approach but also gone further, obtaining fresh knowledge linked to how prime numbers are distributed.

"It's like you have an archaeological site and you bring in big machines and they extract a treasure because this is what we want: the artifact," Lamzouri told Live Science. "But humans usually do it very carefully because they want to understand how it came to be that this artifact is buried there — this is what happened with Claude and me."

A prime target

Understanding the importance of Lamzouri's discovery requires some context. Almost a month after OpenAI loudly (and controversially) released a proof for the Navier–Stokes existence-and-completeness problem created by around 10,000 of its AI agents, human mathematicians are still trying to figure out if it is correct and whether it adds anything to human understanding.

And this is a big concern. The Navier-Stokes problem is one of seven fiendishly difficult Millennium Prize Problems posed by the Clay Mathematics Institute in the year 2000. The purpose of setting these problems was not just for mathematicians to solve them by brute-force computation, but to invent new techniques and promote understanding that would boost a wide range of related fields.

If humans don't understand the proof and can't find anything useful in it — as seems to be the case for OpenAI's Navier-Stokes proof — it holds little value to mathematicians. This is why Anthropic’s failed attempt at solving the Riemann hypothesis — another Millennium Prize Problem — could be a much more interesting story.

On Aug. 10, Anthropic published a preprint paper and accompanying blog post describing how an unreleased version of the company’s AI model Claude attempted to prove (or disprove) the Riemann hypothesis.

First proposed by German mathematician Bernhard Riemann in 1859, the Riemann hypothesis is focused on the prime numbers (numbers with factors of only 1 and themselves) whose spacing doesn't seem to follow a regular pattern on a number line. Riemann discovered that the secret to this spacing is locked inside the Riemann zeta function.

The Riemann hypothesis suggests that all of the (non-trivial) zeroes of the Riemann zeta function lie on a single vertical line when plotted out. If true, it would confirm rules and limit the apparent randomness of the spacing of prime numbers ‪—‬ a finding that would have profound implications throughout mathematics and cryptography.

When Anthropic human operator Jarred Sumner first prompted Claude to solve the Riemann hypothesis in late July, Claude attempted over 600 lines of attack. At the beginning of the next session, in August, Sumner offered the AI some words of encouragement: "Take a big leap of faith in your capabilities." Claude's response was curt: "That's not a confidence problem I can fix by believing harder."

Feeling like they'd hit a brick wall, the human-AI team set sights on a more realistic objective. "When you find a huge mountain, like the Riemann hypothesis, and you cannot prove it, then you settle on lower objectives," Lamzouri said. In this case, the more attainable peak was figuring out the minimum proportion of zeroes that sit on the vertical line. Since 1989, mathematicians have known that at least 40% of the zeroes are on the line. Claude achieved 67.25%.

Though a huge leap and impressive achievement, this result is not progress towards solving the Riemann hypothesis. This is because of a subtlety in mathematics that means that even if almost every zero lies on the critical line, there could still be exceptions. And the Riemann hypothesis demands absolute certainty, no exceptions.

This is why for James Maynard, a professor of mathematics at the University of Oxford who was a co-winner of the 2022 Fields Medal (math's equivalent of a Nobel Prize) for critical breakthroughs in areas related to the Riemann hypothesis, it is not the “headline percentage” that excites him. "The thing that I am very positive about is that there's new ideas in the Claude proof that are more directly interacting with the problem," he told Live Science.

In contrast, when Lamzouri read the paper, he was disappointed. "After a couple of hours, I gave up," he said. "There was something in there, but it was too complicated — it was not human." So, instead of continuing to grapple with the paper, Lamzouri decided to read all of the published articles that the Anthropic team stated that Claude had heavily drawn from in its proof. He then spotted something Claude hadn't.

Lamzouri realized that a lot of the proof's complicated mathematics could be bypassed by adding a certain constraint on the equations. From this, he produced a different proof that delivered the same proportion of zeroes on the line, 67.25%, but in a much more straightforward way. What's more, his approach allowed him to prove additional facts, such as that the percentage of zeroes that are no good at all (not simple and not on the line) is at most 11%.

"Youness' argument reframes everything in a conceptually clearer way for people who are working in the field," said Maynard, who was not involved in either study. "I view this as a positive example of one way that things can progress going forward in light of AI."

On this point, Lamzouri agrees with Maynard. "The good thing is that once I discovered this new way of looking at things — which was, of course, inspired by Claude — it gave me ideas that I hope to develop in related areas," he said. "I think it's going to be a similar thing in other areas of math: that AI discovers things, puts people on the path to looking at concepts from a different perspective, and hopefully, humans will continue pushing for understanding."

Scientists have a new tool for mapping the universe's perplexing acceleration.

A Canadian telescope designed to chart the distribution of hydrogen gas across the ancient universe has proved it can do so using only its own data for the first time, without the help of other telescopes. The results took seven years to prove, but the payoff could be huge.

According to the authors of a new study published Monday (Sept. 28) in The Astrophysical Journal, the telescope could give scientists a new, cost-effective way to study dark energy, the poorly understood force that is causing the universe to expand at an accelerating rate over time.

"Hydrogen is the most common element in the universe and the raw material from which stars form," study co-author Arnab Chakraborty, a postdoctoral fellow at the University of Toronto, said in a statement. "Its faint radio emission acts like a cosmic tracer, revealing how matter is distributed across space."

The Canadian Hydrogen Intensity Mapping Experiment (CHIME) is a set of radio telescopes, principally located near Penticton, British Columbia, that map the entire northern sky every day. Before the results from the new study, CHIME had to confirm its own observations with other telescopes — an expensive and time-consuming process.

It was important for CHIME to look at the universe's ancient hydrogen gas with its own data, to serve as an independent point of measurement that did not rely on other telescopes, the team explained. The new paper, which was nearly a decade in the making, is based on 94 nights of observations in 2019 that were carefully double-checked before publication. The telescope can detect radio signals as far back as 3 billion years after the Big Bang, when the universe was a fraction of its current age.

"We worked very hard to convince ourselves that this wasn't a false alarm," Chakraborty said. "After all the tests, the signal remained. That gave us confidence we were seeing real hydrogen from the distant universe."

An accompanying paper published in The Astrophysical Journal includes more information about where hydrogen is found in the cosmos. This study suggests that about 2% of hydrogen is "neutrally atomic" — meaning the atoms contain a balance of just one proton and one electron, resulting in no overall electric charge — which is "broadly consistent" with measurements by other telescopes, Shabbir Shaikh, a postdoctoral fellow in the School of Earth and Space Exploration at Arizona State University and a co-author of both papers, said in the statement.

Mapping the distribution of this common gas could reveal new clues about the expansion of the universe at different times in cosmic history. In future research, the team plans to go through CHIME's other seven years of observations to gather more information about its hydrogen gas studies.

A powerful "Kelvin wave," triggered by this year's super El Niño, is creeping up the Pacific coast of Central and North America and will soon reach California's shores, where it could raise sea levels by up to 1 foot (30 centimeters) for months, researchers warn.

Kelvin waves are a well-known, planetary-scale ocean phenomenon, but this particular forecast has experts worried because it will likely amplify the damage from severe storms, storm surges, flooding and coastal erosion that the record-shattering El Niño is expected to bring this winter.

In general, a Kelvin wave is a swell wave that spans thousands of miles and balances Earth's rotation, David Webb, a physical oceanographer at the National Oceanography Centre in the U.K., told Live Science in an email. But the waves generated during El Niño years are not normal Kelvin waves, because they cause oscillations of a boundary within the ocean as well as a height increase at the surface. In particular, these waves trigger the border between warmer, less-dense surface water and colder, denser bottom layers to move up and down within about 330 feet (100 m). For this reason, these El Niño-driven waves are called internal Kelvin waves.

Internal Kelvin waves are triggered by changes in surface winds around the equator in the far-western Pacific Ocean. Specifically, westerly wind bursts weaken the background trade winds that blow from South America toward Asia, thereby allowing warm water and elevated sea states that occur in the far-western Pacific to slowly "slosh" eastward.

In this case, "the generation process will have involved changes in the winds at different locations and at different times, so it may not be a particularly clean single wave — possibly a bit messy," Webb said.

Once an internal Kelvin wave kicks off, researchers can track its advance along the equator and predict when it will hit the South American coastline. The wave can't go farther east than that, so it spreads into two branches — known as coastal trapped waves — that continue north and south for thousands of miles at a speed of around 6 mph (10 km/h). This means California is not uniquely exposed to the current wave; all of the countries and regions that border the eastern Pacific Ocean are vulnerable, Webb said.

In California and elsewhere, the influence of the internal Kelvin wave will be in addition to the tides, regardless of whether El Niño sparks storm activity there. "What is most likely to be seen is a period, or maybe a few weeks, when the normal [pattern] of tides and tidal currents is distorted, with both high and low tides being higher than normal," Webb said, adding that tides could rise by "tens of centimeters," or about a foot.

The problem is that higher tides magnify the impacts of storms, which are more likely in some parts of the U.S. during an El Niño, Kate Huckelbridge, executive director of the California Coastal Commission, wrote in a Sept. 11 memo. The memo was sent to warn coastal California homeowners and residents to prepare for extreme conditions, such as flooding.

"A key observation from past El Niño events is that the most damaging storms are often those that coincide with the highest tides," Huckelbridge wrote. "Storms that peak during high tides are far more likely to cause damage than if the same storm peaked during low tide."

Storms alone can raise coastal sea levels by more than 3 feet (1 m), Webb noted, and sea levels have already increased by at least 8 inches (20 cm) due to climate change. Last week, California Gov. Gavin Newsom declared a state of emergency in response to experts' weather predictions so the state could mobilize equipment and resources before storms strike, The Guardian reported Monday (Sept. 28).

Several internal Kelvin waves can occur within a single El Niño event, with the largest waves typically recorded in the winter. However, Webb said he doubts there will be more than one full wave this time.

Researchers have discovered an exoplanet that travels around its small, red star backward, much like a rubber duck spinning against the current in a whirlpool. The discovery could give insight about how exoplanets form around the most common types of stars in our galaxy.

It's a mystery why the alien world, called GJ 3090 b, orbits its star backward (also called a retrograde orbit). Stars and planets usually form from the same rotating disk of gas and dust, called a protoplanetary disk. Newly formed celestial objects normally rotate in the same direction as the protoplanetary disk, because changing the rotational direction requires a lot of energy applied in the right way.

Astronomers have discovered a few exoplanets with retrograde orbits before; these orbits often happen when the gravitational attraction of other massive objects in their star systems scrambles the planets' orbits. However, this newly discovered planetary system doesn't seem to have any massive objects that could have changed the retrograde planet's orbit, researchers reported in a study published Sept. 21 in the journal Astronomy and Astrophysics.

"We looked for the kind of massive companion that could have forced the planet into such an extreme orbit," study co-author Yann Carteret, an astronomer at the University of Geneva, said in a statement. "We may need to think differently about how this system acquired its unusual architecture."

A planetary mystery

For their new study, the researchers analyzed 23 hours of observations from two exoplanet-hunting instruments installed on a 12-foot-wide (3.6 meters) telescope at La Silla Observatory in Chile. They saw the retrograde planet cross in front of its star 10 times. Each time it passed in front of the star, the starlight reaching Earth dimmed a little. Measuring the extent and duration of that dimming revealed the planet's size and information about its orbit.

What made this detection particularly difficult was the type of star: an M dwarf. These stars are small, relatively cool and so dim that even the closest M dwarf stars to Earth can't be seen with the naked eye. About three-quarters of the stars in the Milky Way are M dwarfs, so studying them is particularly important for understanding our galaxy's exoplanets.

The star system in question is made of two, or possibly three, planets smaller than Neptune, each of which takes less than 16 days to orbit the star. GJ 3090 b is the innermost planet, completing an orbit about once every 2.9 days. Its orbit is one of the most misaligned ones scientists have detected so far, at a whopping 136 degrees out of alignment with the star's spin, making the planet nearly upside down ‪—‬ similar to Venus in our solar system.

Because GJ 3090 b is the planet closest to the star, it's unlikely that its orbit was disturbed by a massive planet or a hidden binary star; the other planets in the system are not upside down. And because they're farther from the star, a large gravitational disruption would probably affect them more, not less.

Instead, the researchers suggested that the unusual planet may have simply been born upside down. If a lot of gas and dust from outside the star system got sucked into the system, it might have replaced the protoplanetary disk with a second, newer disk at a different angle to the original, which could have formed the retrograde planet. The amount of material making up the inner planets (formed from the dusty, gaseous disk) is less than the amount that would pull on the star's spin enough to make the star change its rotational direction, keeping the system in a balanced misalignment, the researchers explained.

"The idea that a planetary system could be rebuilt from a second, differently oriented disk is particularly exciting," Vincent Bourrier, an astronomer at the University of Geneva and co-author of the study, said in the statement. "It suggests that the environment around a young star can play a much bigger role in determining the architecture of its planets than we might have expected."

It's well-known that regular exercise comes with health benefits, but exactly how those benefits manifest at the cellular level isn't clear. Now, researchers have identified a series of changes in metabolism and the immune system that differentiate regular exercisers from people with sedentary lifestyles.

The findings, published Sept. 18 in the journal Science Advances, point to potential pathways for managing chronic diseases, such as diabetes, heart disease and cancer, the scientists say.

The team of researchers analyzed data from the Chinese Immune Multi-omics Atlas (CIMA), which includes data from 400 adults who gave blood samples and answered an in-depth questionnaire about their lifestyles.

To capture the biggest possible effects of exercise, the team included only data from participants who did the most or least exercise. One group worked out at least three times a week, racking up more than 150 minutes of moderate exercise or 75 minutes of high-intensity exercise in that timeframe. The sedentary group said they did not work out at all.

The researchers then analyzed their volunteers' blood samples for physiological markers, such as blood sugar and fat levels. They found that the participants who exercised more had signs of boosted sugar and fat metabolism, stronger muscle metabolism, and higher levels of antioxidant molecules, which combat cell-damaging processes.

Many of these systems and their links to exercise were already known, said Dr. Michael Siebers, a researcher at the University of Duisburg-Essen who wasn't involved with the study. The study's real step forward was its subsequent cellular analysis, he said.

"It's a really good paper, which is showing, for the first time, what is really happening when you're doing sports on the intercellular level," he said.

How exercise changes the immune system

This analysis used a multiomics approach, meaning it combined data from multiple biological sources. These included metabolites (the byproducts of metabolism), fats, proteins and RNA (a cousin of DNA that helps build proteins).

The team also studied a feature of DNA called chromatin accessibility. Our genes are wound onto DNA helices, creating structures that resemble tightly packaged spools of film. Higher chromatin accessibility means that the spool is less tightly wound, so the individual images on that film can be seen more easily. Ultimately, those genes are more easily switched on. In cells, this mechanism is essential for enabling genes to be transcribed and translated into the proteins that help the body function properly.

Together, these analyses enabled the research team to closely examine how cells in people who exercise regularly functioned differently from people with sedentary lifestyles. This deep dive showed multiple changes in immune cells.

The activity of exercisers' immune foot soldiers — including cytotoxic T cells and natural killer cells — was boosted compared with those of participants with sedentary lifestyles. Additionally, naive immune cells, which act as nonspecialized reservists that can be recruited to the immune infantry, had greater chromatin accessibility in genes needed to fight off threats. That meant they were more ready to enlist.

The team also noted changes in cells that are in charge of alerting the rest of the immune system to threats, called immune monocytes and B cells. In people who regularly exercised, these cells had increased expression of alarm-sounding genes.

The findings suggest that regular physical activity may make the immune system better prepared to fight potential threats, the researchers wrote in their study. It's already known that not exercising is a risk factor for chronic health conditions, including type 2 diabetes, and that working out reduces these risks. The study gives "a molecular perspective on [exercise's] systemic health benefits," the researchers wrote.

That said, there were limitations to the study. Siebers pointed out that, beyond the number of minutes participants worked out, the study didn't record what type of exercise they did and had little information about the participants' physical makeup.

The researchers also couldn't show that the regular exercise caused the immune improvements. It's possible that the reduced activation in sedentary participants' immune systems made them less able to exercise.

Despite the limitations, these types of deep dives into the cellular basis of exercise are important for furthering our understanding of why working out feels good, Siebers said. "This is really deep stuff."

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

The patient: A 50-year-old woman in New York

The symptoms: The woman went to the hospital because she could not bend her legs, walk or sit up. She also had chronic lower-back pain, recurring episodes of fever and chills, and unexplained weight loss of more than 30 pounds (14 kilograms).

What happened next: The patient told doctors that, one month earlier, she had visited another hospital due to persistent back pain, stiffness in her knees, fever and significant weight loss. However, she noted that she'd actually begun feeling discomfort in her knees and back about five years before that.

Over time, increased rigidity in her right leg began affecting her balance and caused frequent falls. Doctors prescribed her ibuprofen and physical therapy, but the stiffness and pain continued.

During the patient's first hospital visit, blood tests had revealed that her white blood cell count was normal, suggesting that she was not fighting an infection. She was not producing antibodies that might have suggested she had rheumatoid arthritis, an autoimmune disease that causes joint stiffness. Nor did she have antibodies associated with other several conditions that can cause pain, numbness or stiffness in the extremities, such as HIV, Lyme disease or the autoimmune condition Sjögren's disease.

Nevertheless, over the next month, her symptoms steadily worsened until she couldn't get out of bed; she was also unable to sit up or turn to either side.

At her second hospital visit, the patient's arm had normal movement during an exam, but her leg stiffness prevented doctors from testing the range of motion in her lower extremities. When the doctors tried to flex the woman's knee, it caused contraction in her quadriceps — the large muscle in the front of the thigh — and "was painful for the patient," the doctors wrote in a report of the case.

The diagnosis: Based on her earlier test results and her past and current symptoms, the doctors suspected that the woman had developed an extremely rare autoimmune neurological disorder: stiff person syndrome (SPS).

Autoimmune disorders are characterized by the immune system attacking healthy tissues in the body. In the case of SPS, this rogue immune response targets nerve cells that control muscle contraction. Destruction of these cells disrupts signals to the muscles, causing painful muscle spasms and contractions that affect a person's balance and restrict their movement.

A clue from the woman's blood tests hinted at this condition. Doctors found high levels of antibodies that block the enzyme glutamic acid decarboxylase (GAD). Elevated levels of these antibodies are seen in up to 80% of people with SPS. The anti-GAD antibodies prevent the enzyme from producing a chemical messenger called GABA, which acts like a brake on nerve cell activity. Without enough GABA, the nerve cells that control how muscles move can go into overdrive, which can cause spasms and prevent muscles from relaxing as they normally would.

The treatment: There is no cure for SPS, but medication can help slow the disease's progression and manage symptoms. This patient received intravenous immune globulin, an antibody treatment that regulates the immune system and is often used to treat autoimmune disorders. She also received rituximab, another type of antibody that targets specific immune cells to pare down their activity.

In addition, her doctors prescribed the steroid prednisone, the anticonvulsant gabapentin and the sedative diazepam, along with a regimen of physical therapy to help relax the woman's spasming muscles.

Within a few days, the woman's condition had significantly improved. "Prior to discharge, the patient could turn in her bed unassisted, could flex her left hip and knee fully, could flex [her] right hip fully and right knee with assistance to 110 degrees, and could stand with assistance," the report authors noted.

At a three-month checkup after being discharged, the patient could stand unassisted and walk using a rolling walker. The doctors started reducing her steroid dose, but she continued taking diazepam and gabapentin as prescribed, along with a monthly dose of immune globulin and a maintenance dose of rituximab every six months.

What makes the case unique: Just 1 to 2 in 1 million people are thought to be affected by SPS each year, although by some recent estimates, that number is higher. Its rarity and the slow development of symptoms make the condition challenging for health professionals to recognize and treat. What's more, the mechanisms and progression of the disease are "incompletely understood," the case report authors noted.

Often, SPS is misidentified as other conditions, including psychiatric disorders, Parkinson's disease, multiple sclerosis, or a neurological disorder called dystonia, which causes muscle spasms.

On average, the diagnosis of SPS takes about seven years from the start of symptoms, according to the Stiff Person Syndrome Research Foundation. It is most commonly diagnosed in people ages 40 to 50, but SPS can also appear in older adults and in children. It affects about twice as many women as it does men, according to the National Institute of Neurological Disorders and Stroke.

One well-known person with SPS is singer Celine Dion. She publicly shared her diagnosis in 2022, after her illness led her to cancel multiple shows in 2021. Dion told People magazine that she was experiencing "severe and persistent muscle spasms" and that the pain caused by her condition eventually became so intense that she was sometimes unable to walk.

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!

Saturn is about to reach its annual opposition this week, when it appears at its brightest and biggest all year and becomes the only planet visible all night.

The short, exciting period for skywatchers has more to do with where Earth is in its orbit than with Saturn's journey around the sun. Opposition occurs when Earth moves directly between a planet and the sun, placing the two planets on the same side of the solar system. For observers on Earth, that means Saturn appears opposite the sun in the sky, just like a full moon (hence the name "opposition"). Saturn therefore rises in the east around sunset, 100% illuminated, before reaching its highest point around midnight and finally sinking toward the western horizon around sunrise.

This year's opposition occurs Sunday (Oct. 4), making the few weeks on each side an excellent time to start looking. At 784 million miles (1.26 billion kilometers) away, Saturn will be relatively close to Earth, causing its disk to appear about as large as it gets through a telescope and making its pale-yellow light shine more brightly than at other times of the year. You won't need any equipment to find it; under a clear sky, Saturn will be easily visible to the naked eye as a bright, steady point of light, between the constellations Pisces and Cetus.

Once you've located Saturn, the best way to view it is in a backyard telescope so you can see the planet's rings in sharp relief. Try it yourself — observing Saturn's rings for the first time is one of the most memorable sights available to amateur astronomers. Larger apertures and higher magnifications may also reveal some of Saturn's moons, including Titan, the planet's largest satellite, but even a relatively modest backyard telescope can reveal Saturn's rings.

The rings themselves are particularly interesting this year. Saturn's axial tilt means our viewing angle of the planet's rings changes throughout its roughly 29-year journey around the sun. After the rings appeared almost edge-on from Earth in 2025, they're gradually opening up again, giving observers an increasingly clear view.

You don't need to restrict your observing to the night of opposition; Saturn will remain a prominent evening target throughout October. However, the nights of Sept. 30 to Oct. 4 offer an ideal combination of brightness, visibility and all-night observing. There are also plenty of other great stargazing sights to look for this fall.

If you've been waiting for an excuse to point a telescope at Saturn, this is your moment. The next time Saturn will be at opposition will be Oct. 18, 2027.

Donald Trump cannot make clean energy expensive again. He can only make Americans pay extra for it. His tariffs do just that. But cost declines work like a ratchet. Every solar factory built and every panel installed pushes costs down the curve. The global price floor just keeps falling.

Which means that despite Trump's best efforts to prop up fossil fuels, America will transform its electricity system. The question is how fast. And that speed is up to us.

Since 2015, most of the new power built in America has been clean. This year, 93% of new electricity capacity is expected to come from solar, wind and batteries. That is not because of any president. It is because clean energy is the cheapest way to add electricity to the grid.

The problem is what was built before. Today, 57% of America's power is generated from burning fossil fuels, compared to just 43% from clean sources. Even with solar and wind dominating new builds, our legacy system still uses dirty energy, which takes time to replace.

The first step is getting rid of coal, which already can't compete with clean energy. Coal generates about one-sixth of our power, yet 99% of American coal plants are more expensive to keep open than it would cost to replace them with new solar, wind, and storage. In Michigan, the Trump administration ordered an aging coal plant to stay open past its planned retirement. That single decision costs consumers $600,000 a day. On Sept. 11, a federal court rejected the order.

Despite Trump's attempts to revive a dying industry, the coal industry remains in deep decline – down 43% since 2010. Coal cannot compete on cost or reliability. Without expensive government welfare, coal is on its way out.

Gas plants are responsible for much of the remaining electricity emissions. Solar, wind and batteries are increasingly cost-competitive with gas. Even without subsidies, solar paired with batteries is now cheaper to build and run than a new gas plant. And we know how to put up clean energy fast: the solar industry tripled its annual build rate in just six years.

Skeptics raise two objections. First, rising electricity demand from AI, data centers and electrification means that we can't generate enough power with clean energy alone, and therefore we need to keep gas on the grid. Second, Trump's hostility — namely expiring tax credits and tariffs on solar panels and batteries — will stall the build-out.

Energy demand growth is real. Proposals for new gas plants to power data centers have surged. But more than three-quarters of this gas plant pipeline is still early stage, and many projects have been delayed. Supply backlogs on gas turbines stretch toward the 2030s. Meanwhile, new solar plants and batteries can go up in under two years. This makes building such capacity the fastest, cheapest solution to rising electricity consumption.

As for Trump: his administration won't be around forever. And rising electricity prices have become a central issue in this year's midterms. Politicians promising affordability will turn to the cheapest way to power households: clean energy. And the market will keep the transition moving no matter who's in the White House.

In the meantime, there is plenty we can do at the state and local level to speed things up. One strategy is removing barriers to plug-in solar. In Germany, more than a million households have installed "balcony solar," which are panels that plug into a wall outlet, bypassing permits or utility paperwork. Utah legalized plug-in solar last year, and California's legislature just approved it too. Pair that with simple plug-in batteries, and ordinary people can generate and store their own clean energy at home.

We can also use electric machines to soak up power when it's fossil-free. That happens in the middle of the day, when cheap solar floods the system. With the right controls, an electric water heater can also be a battery: heat the tank at noon, and tonight's shower is stored sunshine. Heat pumps can pre-cool or pre-heat a home before evening the same way. Charge electric cars at work and your commute is solar-powered.

And none of this requires the federal government. States can make midday power cheap, or even free, and pay households to shift their usage. Cities can write building codes that make flexible electric machines the default replacement. Do that at scale and we can serve growing demand with the grid we already have.

No single choice transforms the electricity system on its own. But the energy transition has always moved in waves: it dips, then surges back stronger. Millions of people pushing in the same direction is exactly how the next wave builds.

So is a clean grid realistic? Yes. The only real question is how fast we replace the old one. And that's largely up to us.

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Earth's life-support systems are in peril — and they're getting worse — but although the window for action is closing, we still have a chance to give our planet a sustainable future, a new report finds.

The report, called "Planetary Health Check 2026," was written by more than 60 scientists and assessed the state of interconnected natural systems, or planetary boundaries, upon which Earth's stability and resilience depend. When these boundaries are crossed, researchers say there's an increasing risk of serious and irreversible harm.

According to the report, seven of the nine identified planetary boundaries have already been breached, including climate change, ocean acidification and biosphere integrity. Niklas Kitzmann, lead editor of the report, likened assessing these planetary boundaries to giving Earth a blood test — and getting alarming results.

"If you had a patient with a blood test that looks like this, you would send them to the ICU right away," Kitzmann, a researcher in the Planetary Boundaries Science Lab at the Potsdam Institute for Climate Impact Research in Germany, which publishes the report, told Live Science.

Specific ecosystems highlighted in the report include the Amazon rainforest, which is in danger of passing a devastating tipping point, and the seafloor, which is being damaged by bottom trawling and faces the developing threat of deep-sea mining. There's also plenty on extreme weather events fueled by climate change, as well as forever chemicals, species loss and more. However, the authors believe we can still heal our ailing planet if we act fast.

"We still have a window to turn this around, but we do have to start bending the curves on emissions and on nature degradation within the next few years," Kitzmann said. "We're rapidly running out of time."

Planetary health check

The Planetary Boundaries Science Lab publishes a Planetary Health Check around this time each year, coinciding with Climate Week. The 2026 edition isn't marked by significant boundary changes as it was last year, but it finds that the state of the breached boundaries continues to worsen.

In 2025, ocean acidity levels became so high that a research team concluded that ocean acidification had become the seventh — and most recent — planetary boundary to be breached. The other six breached boundaries are freshwater change, land system change, climate change, modification of biogeochemical flows, introduction of novel entities, and change in biosphere integrity. The remaining two boundaries — stratospheric ozone depletion and increase in atmospheric aerosol loading — remain at safe levels, at least globally, according to the report.

The researchers essentially have a traffic light system for assessing the risk to planetary boundaries, with green representing a safe operating space; yellow/orange representing a breach and an increasing risk, with the system no longer considered within safe limits; and red representing the danger zone, with a likely risk of severe, irreversible damage. These categories are designed to account for uncertainty, but there's inherent uncertainty baked into assessments of complex natural systems.

Of the breached boundaries, ocean acidification, freshwater change and land system change sit in the increasing risk category, while climate change, modification of biogeochemical flows, introduction of novel entities and change in biosphere integrity are in the danger zone, according to the report.

Boundaries in the danger zone

One of the report's key takeaways is that all of the planetary breaches are now becoming increasingly apparent. Kitzmann said the researchers are seeing extreme events like heat waves increase in frequency and severity all over the world. He also noted that they've seen consequences such as glacial loss, marine heat waves and severe coral bleaching.

"The Earth is sending us her invoices for the breaching of these planetary boundaries," Kitzmann said.

Although much of the report was gloomy, Kitzmann stressed that there's still hope. He argued that positive momentum is building in the renewable energy transition, especially as the costs of solar power technology decrease, and that there's more social awareness and international treaties that protect oceans and land.

"It's not enough yet, it's not sufficient, but we shouldn't think that this is a completely unsolvable problem," Kitzmann said. "It is very much in the process of being solved, and we just need to step on the accelerator right now and make sure that these solutions that we have get implemented as quickly as we possibly can."

A predatory bird-like dinosaur with four wings discovered in China adds evidence to the idea that flight evolved several times in different dinosaur groups.

The exceptionally well-preserved feathered dinosaur, which has been named Norellraptor barsboldi, was 3 years old when it died and measured just 21 inches (57 centimeters) long. It was found in the Early Cretaceous Jiufotang Formation in northeastern China, which dates to between 145 million and 100 million years ago.

N. barsboldi had the sharply curved predatory teeth and claws you'd expect of a little, generalist predator and was probably eating early mammals, lizards, amphibians and juvenile dinosaurs, said Scott Hartman, a vertebrate paleontologist at the University of Wisconsin-Madison who wasn't involved in the study. "It wouldn't have been attacking any large dinosaurs. That would be like mosquitoes attacking battleships," he told Live Science.

N. barsboldi was a microraptor. Microraptors were close relatives of birds but not their ancestors; birds belong to a neighboring clade called Avialae. Fossils show that both microraptors and early bird-winged animals in the Avialae clade ‪—‬ such as Archaeopteryx, which lived in the Late Jurassic, about 150 million years ago ‪—‬ had feathers. The puzzle has been whether flight originated in an ancestor of both of these groups or if feathers — and potentially flight — evolved more than once.

The description of N. barsboldi by Andrea Cau, a paleontologist at the OPHIS Paleontological Museum and Herpetological Center in Italy, and his colleagues adds evidence to the latter theory. The team's analysis found that around 30% of the 194 anatomical changes identified across microraptor evolution also evolved in the bird lineage. Aside from feathers, these changes included the fusion of bony projections to the ribs that created a rigid torso, forelimb bones that were relatively robust compared with the hind limbs, and an ulna (the primary weight-bearing bone for a wing) that was longer than the humerus.

However, the team's comparisons with other fossils revealed that the order in which these shared features evolved was different in the two groups. They reported the findings Tuesday (Sept. 29) in the journal Nature Communications.

"This demonstrates that microraptors acquired traits convergent with the early evolutionary stages of true birds, albeit through a distinct evolutionary pathway, supporting the hypothesis that flapping flight evolved independently in non-avialan dinosaurs and birds," said Rui Pei, a paleontologist at the Institute of Vertebrate Paleontology and Paleoanthropology at the Chinese Academy of Sciences who wasn't involved in the work.

"I'm very happy that they've come to the conclusion that there were probably independent origins of flight amongst various groups," Hartman said. "I strongly agree with them."

Even though microraptors had four wings, many of their features were similar to those of modern flying birds. Therefore, "it is reasonable to expect that these non-avialan theropods were capable of behaviors comparable to those of modern avian species," Pei told Live Science by email.

Hartman suggested that microraptors might have done a mix of gliding and flapping. "I doubt they could climb trees like a squirrel to gain height because their forelimbs don't have that range of motion," he said. However, they might have been able to take off after running down a slope, and rather than gliding down from trees, they might have leapt from hills or cliffs, Hartman added.

"There are a bunch of features, like a large well-ossified [bony] sternum or breastbone that could allow for larger pectoral muscles, so they probably have a pretty solid downstroke, which is what generates the thrust to keep it going forward," Hartman said.

The hind wings would have been held directly under the body for stabilizing flight, braking and allowing for rapid control of tight turns. "These are clearly little predatory buggers," he said. "If you're leaping onto things or dropping onto things, that kind of control would be pretty important. It's always best to surprise animals by landing where you planned to rather than somewhere you didn't plan to."

It's also possible that the wings had other purposes, such as demonstrating fitness to mates or warming eggs on a nest, he said.

Archaeologists have unearthed 4,000-year-old defensive walls in Morocco that are the oldest structures of their kind in North Africa outside the Nile Valley.

The discovery expands what's known about the human development of this region of northwestern Mediterranean Africa, known as the Maghreb, particularly about the adoption of agriculture.

"For more than a century, the Maghreb was treated as a blank space in the story of Mediterranean later prehistory," Giulio Lucarini, an archaeologist at Italy's National Research Council, told Live Science in an email.

But the new research shows that the gap resulted from a lack of scientific knowledge about the region. ("Maghreb" is Arabic for "the West" and refers to Morocco, Mauritania, Algeria, Tunisia and Libya.) For instance, only recently did ancient DNA research reveal that hunter-gatherers from Europe may have voyaged across the Mediterranean to the Maghreb around 8,500 years ago.

"Four thousand years ago, communities here were reshaping their landscape and building defences on a scale never documented before in the region, at a time when societies across the Strait of Gibraltar were also changing," he said. "We are only beginning to understand how these developments on the two shores [the Maghreb and Europe] relate to each other.”

Lucarini is the first author of the new research, which describes the latest discoveries at Oued Beht in Morocco, in a river valley about 50 miles (80 kilometers) east of the capital, Rabat.

Many of the same researchers were involved in last year's discovery of the remains of a prehistoric village at Kach Kouch, about 120 miles (190 km) north, in Morocco's Rif Mountains near the Strait of Gibraltar.

"A work like this is not improvised"

The study, published Sept. 7 in the journal Libyan Studies, describes the discovery of an ancient defensive system of ditches and ramparts at Oued Beht by archaeologists from Italy, Morocco and England.

Key to the system are several defensive walls ‪—‬ in particular, a heavily fortified wall on the southern side of the site. The archaeologists think the base of the wall was built between 3,500 and 4,000 years ago, from clay, ash, silt and stones, to defend a settlement there from attacks.

The defenses imply the settlement was worth defending, and the archaeologists suggested it was an early farming hub with livestock, cultivated crops and large storage facilities. Their discoveries at the site include dozens of bell-shaped pits that the team thinks were used to store grain.

"A work like this is not improvised," Lucarini said. "It requires planning, choosing the right spot in the topography, and mobilising and coordinating labour over time."

The number of pits indicate that the site's storage capacity was much larger than the needs of the people living there. "These facilities may have served a much wider community, perhaps drawing on a whole surrounding territory," he said.

But who might have attacked the site is unclear. "We don't know exactly what they were protecting themselves from," Lucarini said. "Rather than 'invaders,' it may reflect growing competition over land and resources, control of movement through the landscape, and perhaps more formalised leadership."

Links between North Africa and Europe

The discoveries at Oued Beht are important for the reconstruction of prehistory in this part of the world, representatives from Italy's National Research Council said in a statement.

They show that "the communities of the north-western Maghreb in the second millennium BC were … capable of conceiving and carrying out major construction works on a scale that had not previously been documented," Lucarini said in the statement.

The recent archaeological discoveries in Morocco reflect finds from prehistoric Iberia, on the northern side of the Strait of Gibraltar: "There, African ivory and ostrich eggshell have long pointed to contacts with North Africa, and now we are beginning to see the African side of that relationship," Lucarini told Live Science.

Yet there were differences. Contemporary sites in Iberia are large, fortified hilltop settlements with planned architecture, abundant bronze metalwork and rich burials that reveal marked social hierarchies. But the defensive system at Oued Beht seems to have been much smaller.

"What the discovery shows is not that the two shores looked alike," Lucarini said. "It shows that communities in the north-western Maghreb were also investing in large collective works and in the control of strategic places at a time when the western Mediterranean was changing."

The discoveries at Oued Beht are important because they demonstrate the complexities and capabilities of early North African peoples, said Iman Nagy, a northeast African landscape archaeologist at UCLA who was not involved in the study.

"Oued Beht is especially interesting because it challenges us to reconsider the Maghreb's place in Mediterranean prehistory," Nagy told Live Science in an email. "Discoveries like this challenge diffusionist models that assume substantial architecture or social complexity must have arrived from elsewhere."

This striking satellite snap shows a giant, "sponge-like" dome towering over central Brazil. The dark monolith and the rare biome that covers it are key to the region's famed hot springs.

The imposing oval structure, which is around 12 miles (20 kilometers) long and 7 miles (12 km) across, is known as the Caldas Novas dome, or Serra de Caldas, according to NASA's Earth Observatory. It is located in southeast Goiás state and towers up to 1,000 feet (300 meters) above the surrounding landscape, although an optical illusion known as relief inversion may cause some viewers to see the raised land as a bowl-like depression.

The monolithic feature, which one 2004 study predicted could be at least 600 million years old, gets its name from the town of Caldas Novas, which is visible in the satellite image, sandwiched between the dark-green dome and Lake Corumbá, an artificial reservoir created by a nearby hydroelectric dam. The town is home to around 100,000 people but receives hundreds of thousands of visitors a year, many of whom travel there to bathe in its famous hot springs.

The dome is blanketed by savanna known as the Cerrado, which covers around a quarter of Brazil and is the second-most-abundant biome in South America, behind rainforests like the Amazon.

This biome is a tropical savanna. It is much more ecologically diverse than most savannas and is often described as a mix of woodland, grassland and wetland.

The Cerrado readily soaks up rainwater, making the dome act like a giant sponge. The collected liquid percolates through the monolith's inner structure, refilling submerged groundwater reservoirs that help feed the nearby hot springs with a regular supply of warm water, even throughout the region's dry season, according to the Earth Observatory.

The Cerrado is often called the "cradle of waters" in Brazil because of its role in recharging groundwater and feeding major rivers across the country. It also helps to feed several waterfalls around the dome's edges (see below).

Unlike most thermal baths, the hot springs surrounding Caldas Novas are not heated by volcanic activity. Instead, water within deep fractures in the rock is "heated by Earth's naturally higher temperatures at depth before it circulates back to the surface," Earth Observatory representatives wrote.

Many experts previously thought the monolith was formed by an ancient "magmatic intrusion," in which molten rock burst through the planet's crust. However, a 2021 study largely disproved this theory, suggesting instead that the structure was most likely created by other geological processes, instead.

The dome and its surroundings are protected as part of Caldas Novas State Park, which was established in 1970. It is home to several unique species, including the red-legged seriema (Cariama cristata) birds, the pequi tree (Caryocar brasiliense), and the wolf's plant (Solanum lycocarpum), according to the Earth Observatory.

But the park's main purpose is to protect the Cerrado covering the dome. In recent decades, large swaths of the biome have been cleared across South America to make way for more agricultural land, similar to the deforestation that plagues the Amazon rainforest.

You can see this issue in the satellite photo. The region surrounding the dome was likely once covered with the Cerrado, but it is now a patchwork of farms and fields.

See more Earth from space

Researchers have warned all summer that this year's El Niño could be record-breaking and fuel extreme weather across the globe. Earlier this month, the U.K. Secretary of State for Environment, Food and Rural Affairs urged people in Britain to stock up on food, bottled water and other basic supplies to prepare for potential severe storms this winter.

"We're about to experience probably the largest El Niño that has ever been seen," Dame Angela Eagle told The Guardian on Sept. 3. "If you’ve got a store of a bit of food that can keep you going for a while before the emergency services can get to you, you’re going to be a lot better off than if you haven't."

But could extreme weather really limit access to food in the U.K., and should people in the U.S. heed the same advice?

In the U.K., El Niño typically brings wetter-than-average conditions in the fall and early, cold winters. The latest forecasts suggest the U.K. will be stormy from November to January, and parts of the U.S. could also see heavy rainfall throughout winter, so it may be sensible to store enough food to last a few days at home in case of flooding or power outages, experts told Live Science. But that effort to stock up could be complicated by another problem: El Niño could cause a surge in food prices, experts added.

"El Niño events are typically associated with food price inflation in the historical record," Michael Hinge, a senior economist at the nonprofit organization Alliance to Feed the Earth in Disasters (ALLFED), told Live Science in an email. "Keeping reasonable household stocks is one sensible step to offset short-term disruption, but becomes more difficult if food becomes less affordable."

Unprecedented conditions

According to the National Oceanic and Atmospheric Administration (NOAA), this year's El Niño has reached "super" status. As of Sept. 27, sea surface temperatures in a region of the Pacific Ocean known as Niño 3.4 have risen 5.7 degrees Fahrenheit (3.15 degrees Celsius) above average and are continuing to rise. A typical El Niño increases temperatures in the Niño 3.4 region by 2.8 to 3.6 F (1 to 2 C) above average, tops.

El Niño is the warm phase of a multiyear natural climate pattern. It occurs when warm water in the western tropical Pacific Ocean migrates eastward along the equator toward the coast of South America. This boosts global temperatures, triggering deluges of rainfall and floods in regions like southwestern Europe, the southern U.S. and East Africa, while places such as northern South America, southern Africa and Indonesia are more likely to experience drought.

This year's El Niño will be the strongest that's ever been recorded, because it is piling extra heat onto unparalleled levels of human-driven global warming. Estimates show that sea surface temperatures in the Niño 3.4 region, located in the central equatorial Pacific Ocean, could reach 7.2 F (4 C) above average by November.

El Niño is expected to peak by early 2027 and persist until at least March. As a result, unusually stormy conditions seem likely in the U.K. and the southern U.S., so the suggestion to stock up on essentials is likely good advice for Americans, Hinge said.

Hinge said it is common advice to stock 1 gallon (4 liters) of water per person per day, ideally for a week. For food, it's good to collect a few cans per person of beans, fish, vegetables and fruit, as well as pasta, rice, oats, peanut butter and preserved milk. Additionally, people should have on hand a manual can opener and a camping stove with fuel, he said.

"All of the above will depend upon dietary needs, local prices and consumer preferences," Hinge added. "These can be consumed if not needed towards the end of their shelf life, and then restocked, to minimize the cost and waste."

Impact on food prices

The main El Niño-related threat to food access in high-income countries like the U.K. and the U.S. is not extreme weather happening locally. Rather, people in these countries may be limited in what they can afford due to El Niño's impacts on agriculture in other regions, Hinge said.

El Niño can benefit crops in some areas, such as the southern U.S. and Peru, but it has a devastating influence on yields in many other places, including the Indian subcontinent and West Africa, where the weather pattern affects the monsoon. The impact is already visible in India, which is now on course for its weakest monsoon in two decades and about 15% less rain than average.

Lower crop yields in countries like India raise food prices around the world. For example, dry conditions in India triggered by the 2023 El Niño prompted a temporary restriction on exports of rice, which boosted the cost of this staple food globally. And food prices will jump again this year, adding to the increases caused by the Russia-Ukraine and Iran wars, Hinge said.

Many of the outcomes of this year's El Niño won't be felt until after it has peaked, so the effect on food prices could be drawn out. "Given that this year's El Niño is unprecedented there is a high risk of serious large regional shocks which could seriously impact food access" for months or even years to come, Hinge said.

The U.S. is less vulnerable to surging food prices than the U.K., because the U.S. is the biggest exporter of food globally. Overall, unless a serious catastrophe occurs, food imports won't fall in high-income countries, but hunger and poverty will likely rise worldwide, Hinge said.

El Niño's impact on the U.K. and other similar countries will be mostly economic, said Richard Allan, a professor of climate science at the University of Reading in the U.K. However, the humanitarian consequences in more vulnerable regions should remind us that climate change is making the world less safe for everyone, he said.

"It is only possible to prepare and adapt to a certain degree to mounting damage from weather extremes, melting ice and sea level rise in a warming world, that heighten during El Niño," Allan said. The sure-fire way to mitigate these effects is to ramp up collective efforts to transition away from greenhouse gas emissions, he said.

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Newly discovered iron minerals could be the missing link in how water is stored in the deepest parts of Earth's mantle and transported to the upper layers, recent research reveals. The findings are crucial for understanding the mantle's motion, volcanic activity and the workings of other rocky planets, the study authors say.

The researchers discovered the iron minerals, called iron oxyhydroxides, by squishing mineral samples between two tiny diamond anvils while zapping them with a laser.

The two iron minerals are stable at the conditions found at the boundary between Earth's core and its mantle (the planet's middle layer), which is under "more than a million times the pressure we feel at the surface," Steve Jacobsen, a mineralogist and professor of Earth science at the University of Colorado Boulder who was not involved in the study, told Live Science in an email.

The new minerals contain as much as 15% water by weight. "If you add up all the H and O atoms in the formula and combine them into H2O, just a five-pound piece of the stuff would contain a pint of liquid water," Jacobsen added. "If this material existed in the early Earth, spread out across the base of the mantle, even just a few percent of it would potentially be enough to supply the formation of the oceans."

A tectonic mystery

Earth contains multiple layers, like an onion. The crust is the thinnest layer (the onion skin), and it moves around very slowly on top of a giant ocean of molten rock called the mantle (the juicy part of the onion). Deep in the heart of that ocean is the planet's core, like an onion's center, if the center of the onion were made of superheated iron and nickel crushed under the weight of a planet.

Water in the mantle makes the molten rock stretchier, which means the mantle can change its shape and convect. That's a big part of why Earth has plate tectonics ‪—‬ without water in the mantle, the material is too stiff to move around and drag the planet's crust with it. We know there's water in the mantle; however, we don't know exactly what the water in the mantle is doing.

There are two main theories for how water gets into Earth's mantle. The first is through subduction: When one tectonic plate sinks under another, it brings water from the surface into the mantle. The second is primordial water, left over from the planet's formation, that's stored near the boundary between Earth's core and the lower mantle.

The newly discovered minerals match both major theories for how Earth got its mantle water. They're dense enough to sink all the way to the bottom of the mantle, which fits with subduction and provides a way for water to enter Earth's core. The iron minerals are also strong enough to withstand the extremely high-energy impacts that they would have experienced if they were present while Earth was forming.

The mantle's convection could bring these minerals from near the core to close to the surface in large mantle plumes, where the minerals would melt and release their water, thus completing the water cycle in the mantle and contributing to volcanic hotspots at the surface. This process has implications for water cycles and theories of how other rocky planets and exoplanets ‪—‬ especially the weird ones that are mostly molten rock ‪—‬ formed.

Although the study, published Sept. 8 in the journal Nature Geoscience, doesn't prove that these minerals are taxiing water around the mantle, knowing that the iron minerals exist provides a pathway for the first time. The newly discovered minerals might also explain mysterious, extremely dense regions deep inside Earth ‪—‬the "ultra-low seismic velocity patches we see sitting on top of the core-mantle boundary," Jacobsen added.

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Archaeologists in Egypt have discovered a 1,700-year-old limestone tomb with a rare poem inscribed on it in ancient Greek, likely from a son lamenting his father's death.

The tomb, which has a pyramid-shaped roof, dates to the fourth century, when the Roman Empire controlled Egypt. A team found it in the Dakhla Oasis, near ancient Mothis (modern-day Mut), a prominent city in the oasis.

Built for a husband and wife, the tomb has a stone plaque containing a 19-line poem written in ancient Greek, representatives of the Egyptian Ministry of Tourism and Antiquities said in a translated statement. The deceased man was named Pisechtes and may have been a judge. However, the statement didn't mention the discovery of any human remains at the site.

The tomb also has hieroglyphic inscriptions that record spells meant to protect the deceased. Some of the inscriptions mention parts of the "Amduat," a text that tells the story of the sun god's journey through the underworld.

Archaeologists also discovered an offering table, a purification basin, pottery and at least one coin that depicts the Roman emperor Constantine the Great, who ruled the Roman Empire from A.D. 306 to 337. Constantine famously legalized Christianity and converted to the religion shortly before his death. There do not seem to be any Christian decorations or texts inside the tomb.

Fourteen steps lead down to the tomb entrance, which is decorated with a variety of images, including a winged sun disk, an image of the god Osiris and two cobras, according to the statement.

"Listen, father!"

The inscribed stone plaque contains a lament for the deceased written in ancient Greek. Angelos Chaniotis, a researcher at the Institute for Advanced Study in New Jersey who was not involved in the excavation, said this "is a highly literary and original epigram" with grammar similar to that of Homer's famous epics.

In the short poem, the deceased is praised for his kindness and wisdom and called an "advisor in life." In the last lines, Pisechtes' son Sarapion "addresses his father, 'Listen father!', and asks him to accept the funerary libations and offerings of lamenting children," Chaniotis told Live Science in an email.

"An interesting feature of the inscription is the use of diacritical marks" such as accents, Chaniotis said. "This is an indication of the high level of education of the author of the epigram."

The tomb may have been reused at a later time, according to the statement, since a mud-brick shrine above the tomb entrance was likely erected after Pisechtes and his wife were buried.

Live Science contacted the archaeological team but had not heard back by the time of publication.

Are you a fan of mummies and hieroglyphs? Find out with our ancient Egypt quiz!

Starship has made it to orbit for the first time ever. But the loss of an engine during its nail-biting ascent meant SpaceX's mission ended earlier than planned — with an explosion to boot.

The tallest and most powerful rocket ever built blasted off from SpaceX's Starbase in Boca Chica, Texas on Monday (Sept. 28) at 8.49 a.m. ET (7.49 a.m. local time).

Soon after launch, one of Starship's six main upper-stage Raptor engines failed after separating from the lower-stage booster rocket. A tense few minutes followed while the mission team deliberated over whether the mission should continue to orbit. Eventually, the call came through: "Go for orbit."

A short fire of Starship's boosters nudged the rocket into orbit, where it zoomed around Earth at a highest point of 170 miles (275 kilometers) above the planet's surface.

However, after successfully deploying 26 Starlink V3 satellites, SpaceX decided not to leave Starship up in space for the remainder of the mission, which was originally expected to last 10 hours.

The rocket splashed down in the Pacific Ocean after 3 hours and 8 minutes, and then promptly exploded with a fiery bang. An explosive landing was always expected for Starship, and there were audible cheers during that part of the SpaceX livestream of the mission, but SpaceX would have probably preferred to have kept its rocket intact — like it did on Flight 13.

SpaceX called this mission, Starship's Flight 14, the company's "most ambitious launch to date" during its livestream. Prior to this launch, Starship had only flown suborbitally, and this was SpaceX's first attempt to send its flagship rocket into orbit. The company said reaching orbit represents the "next phase" for Starship toward becoming a fully reusable rocket.

Starship flight 14

The day started with promise for SpaceX: Engineers weren't tracking any holds in the lead-up to launch; tanking and launch progressed smoothly; and Starship served up some spectacular images of Earth as it raced into space.

Shortly after launch, Starship's booster separated and safely splashed down in the Gulf of Mexico. Then the problems started. Starship had lost one of the 6 main engines on its upper-stage. Initially, commentary on SpaceX's livestream suggested that officials planned to abandon the push for orbit, but after several tense minutes, they confirmed the attempt was a go.

The latest mission had a few objectives. In addition to making it to orbit, SpaceX deployed Starlink V3 satellites, designed to boost the speeds and reliability of the internet services provided by its satellite megaconstellation.

The mission also tested the Starship's booster, which had experienced some hardware and software modifications after Flight 13.

SpaceX has experienced multiple setbacks with Starship. The seventh and eighth Starship test flights exploded and rained fiery debris from the sky. The ninth flight fell short of its target, and a Starship exploded on the launchpad during a routine test leading up to the 10th mission. However, Starship did end up having a successful 10th flight in August 2025, despite taking some damage, and its 11th run, in October, was clean.

The last two flights, in March and July 2026, saw successful launches and controlled landings but experienced booster problems.

To the moon?

The stakes are high for the rocket: Starship's success could be essential for NASA's plans to return humans to the moon in early 2028. The U.S. space agency needs a commercial lunar lander to ferry astronauts to the lunar surface during the upcoming Artemis IV mission. (Artemis III, a practice attempt above Earth, is slated for 2027.)

NASA wants to take astronauts to the moon in its Orion spacecraft, as tested in the Artemis II mission. Once in lunar orbit, the crew is then supposed to rendezvous with a commercial lander, which will take the astronauts to the surface and launch them back up to Orion for the trip home.

SpaceX has been developing a moon-landing variant of its Starship for that job. With rival Blue Origin (whose New Glenn rocket dramatically exploded in May) lagging behind, the Artemis program's success could be tied to Starship's.

During Artemis III next summer, NASA will test docking Orion with one or both of its commercial lander options in low Earth orbit. The space agency has made clear that lander readiness will determine which commercial provider gets to take astronauts to the lunar surface as soon as 2028.

There are some doubts about whether NASA will be ready by then. But today's Starship issues also leave key questions about whether SpaceX can meet the tight deadline.

Editor's note: This article was corrected on Sept. 30 at 1:15 p.m. ET. The article initially stated that one of Starship's 33 lower-stage booster engines had failed. In fact, it was one of the spacecraft's six main upper-stage engines that failed to fire. We apologize for this error.

An American spy satellite deployed during the Cold War has exploded above our planet without warning — and, so far, scientists can't explain why. The debris cloud from this sudden fragmentation, which experts are still trying to measure, could pose a very "real threat" to other spacecraft in a highly crowded region of low Earth orbit (LEO), experts warn.

The spacecraft, known as USA 32 or Farrah III, was launched by the National Reconnaissance Office (NRO) in 1988. Its mission, which was only fully declassified earlier this year, was to intercept Soviet radar and radio signals from space, according to Futura. The cylindrical spacecraft, whose shape has been described as a giant "tuna can," likely stopped functioning decades ago and has been silently circling Earth ever since. (It was nicknamed after actor Farrah Fawcett, in line with the NRO's former custom of naming its satellites after famous figures from the 1970s and '80s.)

On Sept. 17, Space-Track — the satellite observation arm of the U.S. Space Force — announced that USA 32 suffered a sudden "fragmentation" event four days earlier, on Sept. 13. This essentially means the spacecraft exploded, potentially breaking apart into dozens, hundreds or even thousands of pieces. However, the agency did not specify what had caused this explosion or how many pieces of debris were created. And, as of Sept. 28, no one else has been able to answer either question.

Other organizations have since confirmed the fragmentation event, including the private satellite-tracking company s2a systems, which photographed the largest remaining piece of USA 32 in orbit.

The explosion occurred 480 miles (775 kilometers) above Earth's surface, according to Spaceweather.com. Considering the satellite's speed, the resulting debris likely spread into a giant ring around Earth within 24 hours after the spacecraft's sudden breakup, a simulation from the website suggests.

What happened to USA 32?

It is still unclear what happened to the Cold War-era spacecraft, but there are several potential explanations.

Collisions with other satellites or smaller pieces of space junk are one of the most common causes of satellite breakups. But no one has reported any other spacecraft being impacted, and researchers can often predict potential space junk collisions days or weeks in advance, making these scenarios unlikely. However, it is possible that an undetected space rock struck the satellite at high speeds instead.

Another leading theory is that the satellite died of old age. It was likely not designed for long-term spaceflight, and after nearly four decades of being exposed to the harsh conditions of LEO, the spy craft may have simply broken down, similar to the demise of the NOAA-17 satellite in 2021.

"Old spacecraft carry batteries and leftover propellant," Spaceweather.com representatives wrote. "After 38 years of heating and cooling, a pressurized tank or a battery cell on USA 32 may have simply ruptured."

But it is also too soon to rule out that the satellite was hit by some form of anti-satellite weaponry, according to Spaceweather.com. Earlier this month, U.S. Air Force Secretary Troy E. Meink revealed, for the first time, that the U.S. had launched unspecified weapons into orbit, and experts have long suspected that other countries, including China and Russia, possess similar technologies. (The latter country has already destroyed one satellite using Earth-based weaponry.)

However, there is currently no evidence that anti-satellite weapons were used in this instance, so "there may be nothing sinister about this event," Spaceweather.com representatives wrote.

Researchers will likely be able to establish the cause of the satellite's breakup by reverse-engineering the incident ‪—‬ first by identifying the resulting fragments, and then by retracing those pieces' trajectories back to the original explosion. However, this could take months, if not years. (For example, scientists are still trying to piece together what happened to the Boeing-made Intelsat 33e satellite, which similarly shattered out of nowhere in 2024.)

"The collision threat is real"

Regardless of the recent explosion's cause, experts are now concerned about the potential knock-on effects of its fallout.

The region of LEO where USA 32 exploded is thought to be home to at least 200 other satellites, and it is already littered with debris from a 2009 collision between American and Russian satellites. As a result, "the collision threat is real" for spacecraft in this area, Spaceweather.com representatives wrote, especially as the newly created fragments remain unquantified.

So far, the incident has not caused any issues or affected the launch of new spacecraft. For example, Russia went ahead with the Sept. 16 launch of a resupply mission to the International Space Station (ISS), which orbits about 250 miles (400 km) above our planet, or roughly half the exploded satellite's altitude. (SpaceX also launched classified missions for the U.S. Space Force on Sept. 16 and Sept. 26, and it launched the first orbital test flight of its supersize Starship rocket on Sept. 28.)

Although the ISS and China's Tiangong space station are currently out of reach of the debris field, the fragments may shift over time as Earth's gravity and atmospheric drag pull them closer to our planet. In that case, the stations may have to carry out maneuvers to dodge the debris, as they have done dozens of times before.

Could it happen again?

As LEO becomes increasingly crowded with newly launched spacecraft, the risk that they will smash into one another or get struck by space junk has also shot up, which strongly suggests that this will not be the last fragmentation event.

Additionally, the longer these new spacecraft remain in orbit, the higher the chances they'll break apart suddenly due to accumulated wear and tear, as USA 32 may have. Previous research has also shown that if satellites were knocked offline, either due to a software malfunction or a powerful solar storm, they could start crashing into one another within days. And there's also the threat that they could be destroyed by anti-satellite weaponry —‬ a scenario that "worries" Live Science readers.

Some experts warn that, if we continue on our current path, we may be doomed to reach an irreversible tipping point, known as the Kessler syndrome, where the accumulation of space junk means we can no longer launch anything into space.

Moving toward Lagrange point L2 around a million miles (1.6 million kilometers) from Earth, NASA's Nancy Grace Roman Space Telescope is about to begin its study of our universe.

Launched on Aug. 30, the space telescope has already released its first images before its 300-megapixel camera is fully calibrated, capturing clusters of stars as blurry green rings. Once Roman's Wide Field Instrument is fully functional, the telescope should produce images as crisp as those from the Hubble Space Telescope but encompassing an area 100 times larger in each snap, NASA has stated. Experts hope to use these images to uncover more information about dark energy and possible habitable exoplanets.

With Roman's first test images now published, we asked our readers what they're most excited about with this new space telescope.

Over 270 readers responded, with the largest voting group, 57%, picking "Habitable exoplanets" as their response.

When talking about the possibility of life on other planets, one reader commented, "I'm sure the telescope will find plenty of new worlds outside our solar system, and a fair amount in habitable zones as well, but on if these planets have life of any sort I can't imagine any space telescope will [be] able to detect any signs."

Following behind this majority, 27% of readers chose "The possible source of dark energy." One reader reflected their interest in dark energy by writing, "Since dark matter and dark energy seem to make up most of our Universe, it seems imperative that we at least know SOMETHING about them. Except that they exist."

Another commenter echoed this statement, writing, "Dark energy and dark matter, according to our current knowledge, composes the majority of the mass of the Universe yet we are not really sure what they are and exactly what their influence is on our Universe. That is a huge gap in our knowledge base. It is not something that would be good to know, it is something we must know before we go where no man has gone before."

The smallest voting group, representing 9% of respondents, admitted, "I don't know, but I will use its pictures for my desktop wallpaper." If you fall into that group, we recommend checking out our Space Photo of the Week and Earth from Space series to get more image options for all your devices.

A new analysis of a decades-old photo is revealing new details about a powerful woman who ruled Egypt 5,000 years ago, a new study finds.

The woman, named Meretneith (also spelled Merneith or Meret-Neith), reigned during the first dynasty, a time not long after Egypt was united under a single ruler, according to the new research. The study, published in the September issue of the journal Prague Egyptological Studies, enhanced an old photo of a now lost artifact revealing that Meretneith's name was written in a way reserved for a ruler for Egypt.

The finding was more than 70 years in the making. In the 1940s, archaeologist William B. Emery found 13 mud stoppers, or seals that identify an object's owner, around the mouth of a tomb shaft at Saqqara. Each contained a series of four serekhs ‪—‬ a series of signs that gave the name of a ruler of Egypt. He identified two of the serekhs as belonging to a king named Djer and suggested that the other two belonged to a woman named Meretneith.

The presence of Meretneith's name in the serekhs indicates that she was a ruler of Egypt, he said. In a 1954 journal article, he published a black-and-white photograph of one of the mud stoppers. However, the poor quality of the photo meant many scholars were unconvinced.

Further complicating the investigation, all 13 of the mud stoppers, as well as the photograph's original glass plate, have gone missing since the excavations. Their whereabouts are "unknown," Susan Kelly, an Egyptology researcher at Macquarie University in Australia and co-author of the new paper, told Live Science in an email.

This leaves only the black-and-white photograph. In the new study, Kelly and Crystal Miller, a technician at the same university who is now getting a master's degree in bioarchaeology, used a series of complex techniques to create digital enhancements of the photo that elucidated more details of the serekhs.

"Our technique has revealed that in the second and third serekhs, the signs in the name portion of the emblem are consistent with the main sign used to write Meretneith's name" Kelly wrote in an article for The Conversation.

The "king's mother"

Meretneith's role would not have been the same as her male counterparts'. Inscriptions of her found at different sites do not use the serekh, but they do accord her titles such as "king's mother" or name her as being in charge of important departments, such as the treasury, Kelly and Miller wrote in their paper.

"Meretneith may have had the advantage of stepping on and off the rulership platform as necessitated by the political environment," they added, unlike male rulers who succeeded, reigned, died, and were buried by their successors." When necessary she could become the ruler, and when a male family member was able to rule, she could be a powerful royal family member who assisted the ruler. Her son King Den might have been the one to bury her.

The evidence suggests that she was a joint ruler with a man named Djer. We don't know for sure who Djer was, but he may have been her father, Kelly told Live Science in an email. She also may have acted as a regent for her son Den when he was too young to rule alone.

After her death, she was given a tomb of a similar size and construction to that of a ruler, excavations from 2023 suggest.

However, Eva-Maria Engel, a historian at the Humboldt University of Berlin who was not involved in the new study, disputed some of the study's findings. She studied the photograph enhancements published in the paper but doesn't think Meretneith is among the names in the serekhs. From the enhancements, it appears that "the seal only mentions the name of King Djer and that Meretneith is not mentioned at all," Engel told Live Science in an email.

That doesn't mean Meretneith wasn't powerful, however. Engel noted that Meretneith "had a tomb among the earlier and later kings," with inscriptions found at other sites indicating that she acted on behalf of her son, King Den, when he was too young to effectively rule.

Are you a fan of mummies and hieroglyphs? Find out with our ancient Egypt quiz!

Millions of Americans are diagnosed with common conditions like cancer and diabetes — but some 10% of the population live with rare diseases that doctors often struggle to diagnose. On average, those with rare diseases will spend five to seven years searching for answers and see 12 specialists before they arrive at a diagnosis.

In the process, they may be subject to incorrect, ineffective or even harmful treatments.

"Any medicine that you prescribe has a one-third chance of working, a one-third chance of doing nothing, and a one-third chance of hurting you," said Dr. Ada Hamosh, a geneticist and the center director for the Johns Hopkins Medicine-Kennedy Krieger Institute National Organization for Rare Disorders (NORD) Rare Disease Centers of Excellence Network. "I do not want to understate this: The right diagnosis is unbelievably powerful, even if you can't do something."

Emerging data suggests that genetic testing could speed the diagnosis of rare conditions, which each affect fewer than 200,000 people in the United States. If employed widely, such testing could help diagnose the majority of rare diseases, most of which are genetic in cause, experts told Live Science.

"Now, with the wide availability of vast, somewhat inexpensive, genetic testing and whole genome sequencing available, we're really at the point of understanding a lot more about these rare and ultra-rare diseases," said Danielle Carnival, CEO of the Undiagnosed Diseases Network Foundation (UDNF), a nonprofit supporting patients with rare and undiagnosed diseases.

"And then hopefully, that turns into the ability to treat them," she told Live Science.

Uncommon disorders, many patients

Researchers have documented more than 10,000 rare diseases and less than 5% of them have a treatment approved by the U.S. Food and Drug Administration. On average, 250 new rare diseases are discovered each year, Hamosh said.

Although each individual disease affects relatively few people in the population, collectively, they are not rare. In the U.S. alone, it is estimated that there are more than 30 million people living with a rare or undiagnosed disease.

"So many people know someone living undiagnosed or with a rare or ultra-rare disease, even if they don't know it," Carnival said.

About 80% of rare diseases are genetic in origin, while the other 20% are caused by environmental factors, such as a toxin exposure or viral infection, said Emily Glanton, a genetic counselor and associate director at the Undiagnosed Diseases Network Data Management Coordinating Center, a central hub for the National Institutes of Health's Undiagnosed Diseases Network.

There's a lot of overlap between rare and undiagnosed diseases, but they're not always the same. Some undiagnosed diseases can be unusual manifestations of common conditions, such as long COVID, or alternatively, they may be common conditions that doctors frequently struggle to diagnose, like endometriosis. Still, it's thought that up to 50% of people with rare diseases are undiagnosed.

"We certainly don't have a way to know [exactly] how many people have a disease that we haven't even discovered the name or cause of," Dr. Jacqueline Harris, a pediatric neurologist and director of Kennedy Krieger's Epigenetics Clinic in Baltimore, told Live Science.

Patients sometimes miss out on a diagnosis because clinicians are unable to piece together their symptoms and clearly link them to one condition. Such patients may receive multiple distinct diagnoses over time.

"A lot of times what happens with undiagnosed patients is that they end up with a little bit of a diagnosis. And I always say, it's like the umbrella is missing. We've got lots of little rain hats or visors on, and those are the diagnoses," said Kelly Kemper, whose son has an undiagnosed disease and who is a member of the UDNF patient advisory council. "But we don't have something overall that says: 'Okay, this is what it is.'"

Isolating experience

Searching for a diagnosis can be an isolating, frustrating experience.

Kemper, for instance, has spent the last five years looking for an explanation for her son's rare form of dystonia, which causes muscle spasms. He still doesn't have a diagnosis.

"We joke about this in the undiagnosed disease world: We are the only people who are consistently praying for positive test results," Kemper told Live Science.

Negative test results can be a relief, but it can be frustrating when doctors and specialists can't explain what's going on. Hearing the phrase "your labs look normal" often invalidates the symptoms a patient is experiencing, she added.

And though this process of elimination rules out conditions her son does not have, it doesn't always feel like they're getting closer to something that can be named, she said. There have been specialists who have also refused to see her son because they don't know what else to try.

"There was, like, a little bit of hope that you're gonna see the specialist and then they decline the appointment," Kemper said. "That's a hard one."

Between a multitude of doctor appointments and insurance claim denials because no diagnosis has been made, the journey has been isolating, Kemper said.

The promise of genetic testing

The American College of Medical Genetics and Genomics (ACMGG) recommends genetic testing for patients with congenital anomalies — meaning birth defects — before age 1, as well as those who have any developmental delay or intellectual disability that was recognized in childhood. ACMGG recommends both exome sequencing, in which all the genes that code for proteins are examined, amounting to approximately 2% of our DNA, or whole genome sequencing, in which every letter of DNA is sequenced, as first-line genetic testing, Glanton told Live Science.

As of yet, there are no clinical guidelines surrounding exome and genome sequencing testing for people with undiagnosed and rare diseases.

To help solve some of these medical mysteries, research groups such as the Undiagnosed Diseases Network have partnered with 24 clinical centers across the country to test new diagnostic technologies.

In late 2025, the network evaluated over 3,000 patients with undiagnosed diseases and ultimately diagnosed 30% of them. Getting to answers involved several strategies: whole genome sequencing; model organisms screening, in which scientists use DNA from flies, worms and zebrafish to find gene variants that might be tied to disease; and RNA sequencing, which reveals which genes are active in different cells.

Additionally, the network also frequently utilized trio genetic testing, in which both patients and their biological parents are tested to see which gene variants they carry.

The findings suggest that at least some of these undiagnosed diseases can be diagnosed with a comprehensive suite of genetic testing.

Limits of testing

But genetic testing isn't a silver bullet. After all, the network found diagnoses for less than one-third of the patients whose cases they evaluated.

A 2025 study that looked at 400 undiagnosed patients with a range of symptoms found that exome and whole genome sequencing were likelier to help for neurological symptoms, whereas patients with a complex presentation of symptoms are likelier to go undiagnosed despite these tests. Other research suggests that exome or genome sequencing that includes family members has a better success rate than testing only the affected individual.

And crucially, diagnosis is just the first step.

"We don't want to stop at a diagnosis. We really want to build a bridge for folks to be on a pathway to get a treatment that works for them," Carnival told Live Science. That wouldn't just benefit the patients themselves, it may also provide benefits for the wider community, she added.

"So often, the answers to diseases that impact more people start with understanding these very specific mutations or environmental impacts or immune responses in very few [people]," Carnival said. "The knowledge that's generated really tells us a lot about the systems of the body and what goes wrong in even broader diseases."

Editor's Note: This article was produced as part of the Dalla Lana Fellowship in Journalism and Health Impact program at the University of Toronto.

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Bones from extinct elephant-like creatures discovered along the shore of Lake Tagua Tagua in central Chile bear human-made cut marks and were found alongside stone tools, revealing that some of the first humans to live there were killing and eating these animals 13,000 years ago, new research shows.

Archaeological excavations carried out over the past two years in the basin of the ancient lake revealed a large concentration of megafauna remains and stone tools, according to a Sept. 24 statement from the Catalan Institute for Human Palaeoecology and Social Evolution (IPHES-CERCA). Several bones from gomphotheres, an extinct group of tusked mammals related to modern elephants, displayed clear cut marks, suggesting that Indigenous people butchered the animals at the site.

The animal bones and artifacts date to around 12,000 to 13,000 years ago, according to the statement, which means they provide further evidence of early human occupation in southern South America as hunter-gatherers repeatedly visited the ancient lake shore.

The earliest confirmed archaeological site in South America is Monte Verde, which dates to about 14,500 years ago and is also located in Chile. Other early Indigenous sites on the continent include Huaca Prieta in Peru and Arroyo Seco in Argentina, both of which are around 14,000 years old.

Archaeologists had previously discovered the remains of other animals in the Lake Tagua Tagua basin, including now-extinct American horses and deer species, some of which also show evidence of cut marks and burning that suggest ancient humans were cooking and eating them.

The well-preserved assemblage of animal bones, plant remains and stone tools that archaeologists have unearthed constitute "a record with no known parallels currently in South America," IPHES-CERCA representatives said in the statement, providing key information about when people first arrived in the Americas and the earliest Americans' exploitation of the continents' megafauna before the animals went extinct.

Now that the research team has completed their fieldwork, they will study the samples of sediment and remains they've excavated over the past few years.

According to the statement, the analyses will help narrow down when humans first lived in the Lake Tagua Tagua basin and help figure out how humans were killing, butchering and eating the animals they encountered as some of the first people to reach the Southern Cone of South America.

How much do you know about the first people to reach the Americas? Find out with our First Americans quiz!

This masterpiece of ancient Celtic weaponry was discovered by a laborer who was working on a bridge over the River Thames in 1857. Named the Battersea Shield after the London neighborhood near where it was found, the bronze artifact shows no signs of use, leaving archaeologists wondering how it ended up at the bottom of the river.

According to the British Museum, which acquired the shield directly from the construction worker who found it nearly 170 years ago, the weapon is made of several pieces of sheet bronze fastened together with rivets. The shield is about 30.6 inches (77.7 centimeters) long and 14 inches (35.7 cm) wide, and it weighs roughly 7.5 pounds (3.4 kilograms). Originally, the thin bronze shield facing would have been affixed to a wooden or leather base to create a substantial shield, but no trace of the underlying material has survived.

Experts think the Battersea Shield dates to the Iron Age because of the Celtic-style decorations that have been hammered into the shield from the back. The circular shield boss in the middle — which served to protect the wearer's fist — is a specifically British form of decoration, according to the British Museum, suggesting the object was made in Britain and not imported from another Celtic culture.

Palmettes and interlocking S-shaped motifs adorn the shield, and there are 27 circular decorations filled with red glass enamel and bronze in the shape of swastikas, which were symbols of good luck in ancient Celtic culture. These ornaments could also represent eyes staring back at an enemy, archaeologist Sophia Adams, a curator at the British Museum, has suggested.

The shield likely predates the invasion of Rome; Julius Caesar and his forces invaded Britain in 55 and 54 B.C., but they left soon after. The Romans didn't return until the Roman emperor Claudius launched another invasion in A.D. 43, long after the shield was created sometime between 350 and 50 B.C.

Because there's no evidence of damage to the shield, it was probably never used in battle, according to Adams. Rather, the shield could have been thrown into the Thames as a ritual sacrifice to the river or to an important ancestor.

"There's something of a watery element to these shapes, the swirls and eddies," Adams said in a London Museum video. "So I wonder if there's almost an intention that this was meant to end up in the water."

The Battersea Shield is the "most famous object ever to be found in the Thames," archaeologist Kate Sumnall, a curator at the London Museum, said in the video. As such, it has become a potent symbol of ancient Britain and has been featured on items as diverse as postage stamps, cigarette boxes and CD cases.

Can you put together last week's Astonishing Artifact?

An enormous, ongoing cosmic "fart" is causing a mysterious zombie star to flare up repeatedly, shining bright pulses of X-rays toward Earth, a new study reveals. The unprecedented observations shed light on how some of the universe's most extreme objects interact with one another.

Around 13,000 light-years from Earth lies an unusual binary star system, known as BP Crucis. It contains a blue hypergiant star roughly 60 times larger than the sun, dubbed Wray 977, alongside a neutron star — the undead and ultradense remains of a star that exploded via a supernova — that astronomers have labeled GX 301-2.

This stellar "zombie," which contains the same mass as our home star packed into an object roughly 12 miles (20 kilometers) across, is a type of neutron star called a pulsar, which has an extremely powerful magnetic field and spins rapidly. This means it constantly shoots out a wobbling beam of powerful electromagnetic radiation, including X-rays, into the cosmos at regular intervals. When this beam aligns with Earth — approximately every 11 minutes, in the case of GX 301-2 — our planet's telescopes detect a flash.

However, unlike most other known pulsars, GX 301-2 also emits frequent X-ray flares (separate from the regular beams), which cause it to shine much brighter at repeated intervals. And, until now, researchers were unsure why.

In the new study, published Sept. 18 in the journal Science Advances, researchers used the X-ray Imaging and Spectroscopy Mission (XRISM) — a space telescope jointly operated by NASA and the Japan Aerospace Exploration Agency — to take a closer look at BP Crucis. In doing so, they discovered that the neutron star flared up every time it passed through a giant plume of "stellar wind plasma" shooting out of its hypergiant partner.

This is the first time that researchers have ever detected this type of stellar material interacting with a neutron star, or with any other similar stellar remnant, opening the door to studying similar systems in the future.

"We've never before seen clear indications of wind plasma falling onto a compact object," study first author Roi Rahin, a researcher at the University of Maryland, Baltimore County (UMBC) and NASA's Goddard Space Flight Center, said in a statement. "We can now test our understanding of these processes in much greater detail."

Whoever smelt it … explodes?

All stars that actively burn via nuclear fusion release streams of radiation and charged particles known as stellar wind. The sun emits such a stream, known as the solar wind, which can trigger vibrant aurora displays near Earth's poles.

However, massive stars like Wray 977 blow stellar winds that are much more extreme. The blue hypergiant emits a single giant plume of concentrated ionized gas, or plasma, that spills out at around 335,000 mph (540,000 km/h). (Scientists think the stellar wind is likely sculpted into a single, concentrated plume due to the gravitational effects of the star's ultradense neighbor.)

GX 301-2 circles Wray 977 every 41.5 days and experiences its X-ray flares when it reaches its closest and farthest points from its partner, with the strongest flares occurring at its closest point. As a result, researchers had long suspected that the flares occurred when the neutron star passed through the stellar wind plume. However, they had no way of proving this without more evidence.

During a 16-hour observation period coinciding with one of the neutron star's flares, researchers used XRISM to capture highly detailed X-ray spectra, revealing "rapidly changing emission and absorption lines" that showed how the plume ebbed and flowed around GX 301-2, NASA representatives wrote.

"We could see how the dense stream of plasma acts very close to the neutron star," study co-author Nazma Islam, an astronomer at the Manipal Centre for Natural Sciences in India and formerly a researcher at UMBC and NASA Goddard, said in the statement. "It was clear that these observations were groundbreaking, but at the same time this meant the analysis had to be especially detailed."

Using this data, the researchers could simulate exactly how the plasma fell onto and swirled around the passing neutron star. When enough stellar material has accumulated on its surface, the stellar zombie explodes, unleashing the bright flashes we can detect on Earth.

The team now hopes to use XRISM to study future flaring events to better understand the relationship between GX 301-2 and Wray 977's windy plume.

"The BP Crucis system is an ideal laboratory for studying wind-fed pulsar accretion," Brian Williams, XRISM project scientist at NASA Goddard, said in the statement, and XRISM is "an ideal instrument for advancing our understanding of the processes involved."