The saying that "all roads lead to Rome" may be famous, but a new study finds it's far from true. Extensive new research of the Roman Empire's road system reveals that several other Roman cities were better connected than the Eternal City was during antiquity.

Major cities like Antioch, Ancyra (modern-day Ankara) and Byzantium in what is now Turkey, as well as Corinth in Greece, were "better located than Rome" for those traveling by land, the team wrote in a paper published Tuesday (Sept. 15) in the journal Nature Communications.

At its height in A.D. 117, the Roman Empire covered almost 2.1 million square miles (5.5 million square kilometers) around the Mediterranean Sea, occupying much of Europe, the Middle East and North Africa, the team noted in the study.

For years, the scientists have been creating a vast digital atlas called "Itiner-e" of nearly 186,000 miles (300,000 kilometers) of Roman roads. For the new study, they calculated how well Roman cities were connected to the road system.

In fact, the empire's "most important intermediary route" by land identified in the study didn't even run through Rome.

"It follows the North African and Levantine coast past Antioch and near Ankara, crosses over to Europe at Constantinople, and moves through the Po Valley and Milan into France," study co-author Tom Brughmans, a professor of classical archaeology at Aarhus University in Denmark, told Live Science in an email.

The other well-connected cities had a bevy of reasons for their numerous roads. For instance, Corinth was better connected to the road network because the roads that ran through it linked the Greek Peloponnesian Peninsula to the rest of Greece, and Ancyra was better connected because it was a vital transportation hub for Anatolia.

Rome's unique location is likely the biggest reason why it wasn’t as well connected to the road system as these other cities.

Brughmans noted that the "Italian Peninsula is an appendix to the empire's road network, and Rome is halfway down this appendix." And when "we consider all movement within the entire Italian Peninsula, we were shocked to discover that the most central road actually follows the opposite Adriatic coastline, bypassing Rome altogether," Brughmans added.

The study also found that when the shape of the land allowed it, Roman roads tended to be straight, but they were not as straight as modern-day roads.

Today, "modern road building avoids sharp turns and aims to build as straight roads as possible by strongly modifying the terrain to facilitate faster travel by car, which is made possible by modern surveying and construction methods," the team wrote in their paper.

Sea and river connections

Although the new research sheds light on road connections, it's important to remember that road travel wasn't the only means of transport in the Roman Empire. In fact, the researchers noted that Rome may have had a more significant position for sea and river transportation than it had for road transportation.

Although the study didn't look at waterways, Rome's central location in the empire meant that it would have been an important hub of water transport, the team wrote in the study.

"Rome's central location is not due to its roads, but its physical location in the centre of the Mediterranean, on the nexus of major shipping lanes," Brughmans explained.

The team said future studies should examine sea and river transport and integrate their findings with the team's Roman roads study. When considered together, road and waterway routes may help researchers better understand Roman transportation networks.

Pažout, A. et al. (2026). Network science reveals the structure and lasting impact of the Roman road system. Nature Communications, 17(9551). https://doi.org/10.1038/s41467-026-75453-3

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

Paleontologists have identified the first confirmed remains of Diplodocus — "Dippy," for short — outside the western U.S., revealing that the iconic long-necked dinosaur reached what is now Spain roughly 150 million years ago.

The findings show that the enormous sauropod didn't live only in North America, as was long thought. Instead, it may have rambled across a land bridge all the way to Europe, the new study suggests.

The discovery, made at the La Tejería site near the small village of El Castellar in eastern Spain, provides some of the strongest fossil evidence yet that dinosaurs could move between North America and Europe during the Late Jurassic, when the Atlantic Ocean was still in its early stages of opening after the breakup of the supercontinent Pangaea. The researchers published their findings Tuesday (Sept. 15) in the Journal of Vertebrate Paleontology.

"Paleontological studies like this one help us better understand the history of life on Earth, reconstruct ancient ecosystems, and understand how they changed through time," study first author Sergio Sánchez Fenollosa, a doctoral student who studies biodiversity and evolutionary biology at the Joint Paleontology Foundation Teruel-Dinópolis (Dinópolis Foundation), a paleontological research institution, told Live Science via email.

A sauropod in Spain

Dippy is one of the best-known dinosaurs. After its fossils made their grand debut at the Carnegie Museum of Natural History in Pittsburgh in the early 1900s, life-size fossil replicas of the towering herbivore were sent around the world, including to England, France, Spain, Argentina and Russia.

But until now, Diplodocus' Late Jurassic fossils were known only from the Morrison Formation in the western United States ‪—‬ and the latest discovery shows that Dippy wasn't a homebody.

The newly unearthed Diplodocus specimen consists of 14 well-preserved tail vertebrae and several chevrons ‪—‬ bones that helped support blood vessels and muscles within the dinosaur's tail.

Study co-author and managing director of the Dinópolis Foundation, Alberto Cobos, said it was a friend who "thought he had spotted some bones on a mountainside," Cobos told Live Science via email. "That very day, I went to the site near El Castellar (a village in the province of Teruel). Sure enough, we saw a couple of sauropod vertebral centers."

Although only part of the skeleton has been recovered, the bones show a series of characteristics associated with Diplodocus, including large cavities corresponding to where air sacs would have been, along with deep grooves running alongside the underside of the tailbones.

"It was an exciting and continuous process of seeing the pieces of the puzzle gradually fall into place," Sánchez Fenollosa said in a statement. "From the early stages of the osteological study, we noticed strong similarities with several diplodocine sauropods … With each new result, the picture became clearer: we were looking at a Diplodocus."

It's unclear which species of Diplodocus the new specimen is, but like others of its genus, it was a huge dinosaur with an extremely long neck and whip-like tail.

"The Diplodocus from El Castellar was approximately 25 meters [82 feet] long (comparable in size to its North American relatives), making it another of the giant sauropods of the Spanish Jurassic," Cobos said in the statement.

An ancient bridge

Between 195 million and 170 million years ago, the supercontinent Pangaea broke apart as the Atlantic Ocean opened. But the ocean was much narrower than it is today, and the continents were not necessarily as isolated as their modern geography is now.

Evidence indicates that temporary land bridges may have allowed some animals to move between the two regions. The most famous prehistoric land bridge is the Bering Land Bridge that humans used to move between Asia and what is now Alaska. Previous research showed the Bering Land Bridge also existed around 68 million years ago, and it may have allowed an Asian ancestor of Tyrannosaurus rex to trek into North America.

One possible route for Diplodocus into Spain may have been a land bridge that connected what is now Newfoundland with the Iberian Peninsula.

Geological conditions may have allowed dinosaurs like Diplodocus to move between continents, Sánchez Fenollosa told Live Science in an email. "This interpretation is supported not only by the fossil record but also by geological evidence," he said.

The newfound Diplodocus fossils also suggest that the distribution of giant sauropods was more complicated than the fossil record previously indicated.

"More complete specimens will be essential to understand this story in greater detail, particularly to determine which Diplodocus species inhabited Europe: whether it was one already known from North America or a previously unknown species," Sánchez Fenollosa said. "This discovery reminds us that even for such iconic dinosaurs, there are still many unanswered questions about their evolutionary history and biogeography."

Climate change is often discussed in terms of rising temperatures, extreme weather and environmental loss. But there's another consequence that can be harder to see: The impact on our mental health.

In this exclusive video, we explore how heat exposure influences mental state, drawing on research by Kim Meidebauers, a neuroscientist at Washington State University who studies the effect of heat on emotion and behavior.

Burning up: How can we adapt to a warming world?

As the planet warms, our environment will be transformed, but so will our bodies. This video is part of a series where we investigate the health impacts of climate change, focusing on heat, air quality, food and infection risk. We also evaluate the promising solutions that could help us adapt to our warmer future.

This eye-catching astronaut photo shows the point where an ancient Patagonian lake has been split by a peculiar land bridge, creating two contrastingly colored bodies of water.

Lake Pueyrredón (on the left in the photo) is the Argentine half of a roughly 40-mile-long (65 kilometers) glacial lake, which stretches across the country's border with Chile in Patagonia — a region in South America that is well known for its diverse range of geographic features, including mountains, fjords, deserts and rainforests. The Chilean half of the lake is known as Lake Cochrane (not shown in this image). Both halves hold crystal-clear water that is up to 1,600 feet (500 meters) deep, giving Pueyrredón a deep blue hue when viewed from above.

Thousands of years ago, a thick sediment barrier formed across the southern section of Lake Pueyrredón, creating a new body of water known as Lake Posadas. This smaller body, which is roughly 5 miles (8 km) long, has a lighter, teal color due to its shallow water and a large influx of sediment from a nearby river, according to NASA's Earth Observatory.

Other rivers from nearby hills have previously dumped large quantities of sediment along the western shore of Lake Pueyrredón (bottom of the photo), creating a trio of fan-shaped landforms, known as deltas, that increase in size from north to south (left to right in the photo).

Wind-driven currents and waves have pushed some of this sediment from the outer edges of the two smaller deltas, creating long, thin strips of land, known as sandspits, pointing down-current.

The strip of land separating Pueyrredón and Posadas looks similar to the sandspits. However, it is most likely a moraine — a barrier of sediment and larger rocks that formed along the edge of a hefty iceberg or long-lost glacier, according to the Earth Observatory.

Eagle-eyed viewers may be able to spot a narrow airstrip on the smallest delta (running almost parallel with its sandspit). While the area is largely uninhabited, it is popular with tourists, who travel to the lakes to camp, hike, fish and kayak, according to a local travel site.

Lake Posadas is also home to a unique island with a massive rocky arch (see below) that is also popular with tourists.

The two lakes in the astronaut photo sit within a large valley, which was carved by a massive ice sheet that once covered the area. The last remnants of this ice sheet are located in northern Patagonia, around 20 miles (30 km) west of Lake Cochrane, and have also been snapped from space by astronauts.

Patagonia is home to dozens of similar valleys and fjords that were carved out by the same massive ice slab. Around 210 miles (340 km) southwest of Pueyrredón and Posadas, a trio of ravines converge to create a rare configuration where a lake, river and glacier "touch" each other at a single point.

See more Earth from space

A volcanic eruption 22 million years ago froze a snapshot of the Andes in their youth, revealing a slow-and-steady formation of this formidable mountain range.

The eruption, which originated from the Lauca Caldera in what is now northern Chile, blanketed the landscape in a formation known as ignimbrite. This rock is left over after a pyroclastic flow ‪—‬ a mix of rock, volcanic gas and ash that sweeps over the landscape like a broiling tsunami. Pyroclastic flow is what buried the Roman town of Pompeii after the eruption of Mount Vesuvius in A.D. 79, preserving buildings and people where they fell.

Now, a new study published Sept. 11 in the journal Science Advances extrapolates the landscape under this Andean ignimbrite, revealing that it must have buried rolling foothills rather than craggy peaks.

"Pompeii shows how volcanic eruptions can freeze a moment in human history," Byron Adams, a geomorphologist at University College London, said in a statement. "This study shows that much larger eruptions can also freeze moments in Earth history, burying whole landscapes beneath volcanic deposits and preserving clues to how mountains were being built before the eruption. We cannot dig down to see the buried landscape, but we can use the shape of the volcanic blanket and what we know about how rivers shape mountains to infer what is hidden beneath it."

The original slope of the volcanic flow from Lauca Caldera was about 1.5 degrees, Adams and his colleagues wrote in the new paper. The researchers also calculated the erosion of the landscape to figure out how fast the rocks in the area were rising as the oceanic Nazca Plate pushed under the continental crust of South America, which is how the Andes were built.

They found that prior to the eruption, the uplift of the crust was no more than 0.16 mile (0.26 kilometer) per million years — quite a sluggish process. This finding corresponds to earlier work that used the formation of certain minerals within rocks to determine when a particular rock rose through the crust and approached the surface.

"There is debate over whether the Andes grew slowly and steadily over 40 or 50 million years or whether they rose extremely slowly and then popped up more recently, in the last six to 10 million years," Adams said. "Our findings, which cover a large part of the middle of that history, support the slow but steady hypothesis."

The same method could be applied to other mountain ranges worldwide, the researchers added.

Scientists have a new view of the ground under Los Angeles, and it's a bit shaky.

The 3D model of the Los Angeles basin shows that downtown LA is underpinned by up to 6.2 miles (10 kilometers) of sediment, which will likely amplify shaking from any earthquake that hits the region. That's not entirely new information, but the underground map is more precise than ever before, and it should help earthquake scientists better understand which areas of the city are most vulnerable.

"With this improved model of the basin, we now know the shape of the edges of the basin in a lot more detail," Elizabeth Cochran, a U.S. Geological Survey seismologist who was not involved in the study, told Live Science.

That's important, Cochran said, because irregular edges can focus or direct earthquake waves. In the magnitude 6.7 Northridge earthquake in 1994, Santa Monica experienced more shaking damage than expected because of the way the seismic waves traveled along the basin edge, she added.

Los Angeles sits in a sedimentary basin, a low spot where layers of sediment have accumulated for at least 15 million years. At first, the basin was underwater, so the lowest layers of these sediments were oceanic sediments. Later, when tectonic forces brought the basin onto dry land, additional sediment accumulated from the mountains nearby.

Researchers knew the general shape of the basin, but not in great detail. "Previous surveys were just linear arrays that went through just one cross section on the LA Basin, but this was the first full three-dimensional map," said Valeria Villa, a doctoral student at Caltech and co-author of the new paper describing the map, published Aug. 4 in the journal JGR Solid Earth.

The data from the new map came from 273 temporary seismic stations deployed around LA. These stations detected faint earthquake waves from distant quakes that couldn't be felt by humans. The paths and timing of these waves as they traveled helped researchers build a 3D map of the rock layers below the surface.

The central part of the basin, under downtown LA, holds the deepest sediments, which could amplify shaking. The edges of the basin are thinner, with 0.6 to 2.5 miles (1 to 4 km) of sediment before the hard crystalline rock that serves as the basin's bottom.

On its own, the map doesn't tell geophysicists exactly where shaking might be the worst in the case of a big LA earthquake, but researchers can now update their models and simulations to test different scenarios, Villa told Live Science. The damage will ultimately depend on a lot of factors, such as which fault causes the quake. Los Angeles is surrounded by many faults, including the famous San Andreas, which could give off a magnitude 7.8 quake that would jolt Southern California.

One important factor in the amount of damage to buildings during such a quake is "resonance" ‪—‬ whether buildings shake in time with the sediments below them, Cochran said. When buildings and sediments are in resonance, the damage is worse. A better understanding of the sediment layers beneath downtown LA will help researchers ensure buildings are designed to avoid resonating with the shaking basin, she said.

"You can, for example, change the stiffness of your building and do other things to offset this effect," Cochran said. "What is important is that you know what the ground is like, and what the larger geologic structure is like, underneath the region where you are building the building to know that this could be an issue."

In the Kingdom of Benin, one of the oldest monarchies in West Africa, a traditional ruler known as an oba would commission a brass or bronze bust of their predecessor upon taking the throne. The bust of the past oba would then be set on an ancestral altar in the palace. But when the British Empire annexed the Kingdom of Benin into colonial Nigeria in 1897, the British looted thousands of African artifacts spanning the kingdom's seven-century history, and the country of Nigeria has asked that they be returned.

This particular bust is in the collection of the Cleveland Museum of Art (CMA), which acquired it from prominent French art dealer Louis Carré, who sold many of the artifacts looted from Benin to Western museums in the 1930s. This head of an oba ancestor, also known as "uhunmwun-elao" in the Edo language spoken in the historic Kingdom of Benin, is roughly 1 foot (30 centimeters) tall and was made from a copper alloy, using a lost-wax casting process that would produce one unique bust, then-CMA curator William Milliken wrote in a 1937 study.

Initially, CMA experts thought the ancestral head represented a princess, due to the layers of coral necklaces around the oba's neck and the thin braids hanging from the individual's temples. But the coral necklaces and the lattice-pattern beaded caps were actually potent representations of a ruler's power. The top of the bust is partly open, and it would have supported an intricately carved elephant tusk that recorded the oba's accomplishments and major life events.

Many of the surviving ancestral commemorative heads were created in the 15th and 16th centuries by the Igun Eronmwon, a hereditary guild of brass and bronze artisans that made objects for royalty in the Kingdom of Benin. According to the CMA, Benin royalty prized brass because it does not corrode. Much of the African brass was imported from as far away as Germany.

When British forces invaded the Benin royal palace in 1897, they looted thousands of metal plaques, sculptures of humans and animal figures, and royal and personal ornaments that have come to be known as the Benin Bronzes, even though most of the objects are technically brass, an alloy of copper and zinc. The British Museum holds the world's largest collection of Benin brass artifacts — over 900 objects — which Nigeria formally requested be returned in 2021.

Some institutions have begun repatriating this historic royal art back to its homeland. A group of German museums that collectively held over 1,100 of these objects transferred ownership of them to Nigeria in 2022. That same year, the Smithsonian's National Museum of African Art transferred ownership of 29 Benin Bronzes to Nigeria. And, in 2025, the Netherlands returned 119 Benin Bronzes to Nigeria. To date, however, the British Museum has not officially returned any of the Benin Bronzes in its collection.

There is also controversy about who should have ownership of these artifacts. In 2025, the Museum of Fine Arts, Boston returned two Benin Bronzes to Oba Ewuare II, the great-great-grandson of the last oba before the 1897 British invasion. Oba Ewuare II is the Oba of Benin and custodian of Benin culture.

A full catalog of royal artifacts looted from Benin in the late 19th century can be found on the Digital Benin project website.

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

Can you put together last week's Astonishing Artifact?

In women's reproductive years, their brains are exposed to high levels of sex hormones, and their neurons may come to depend on those hormones to function optimally. But leading up to and after menopause, the ovaries produce far less estrogen and progesterone, raising concerns that this drop in hormones may contribute to women's dementia risk.

"We think that the loss of those hormones at menopause renders those neurons more vulnerable to age-related cellular decline and pathologies like Alzheimer's," said Karyn Frick, a neuroscientist and professor of psychological and brain sciences at the University of Wisconsin-Milwaukee.

So, if falling hormone levels are a risk factor for dementia, could replacing those hormones help stave off the disease?

While the idea sounds logical on its face, studies that have looked at hormone replacement therapy (HRT) for dementia prevention have had mixed results. There are early hints that restoring estrogen during early menopause may protect brain health, but ultimately, more gold-standard clinical trials are needed to know for sure, experts told Live Science.

Support for estrogen protecting the brain

The idea that estrogen could help ward off dementia is plausible. Women are more likely to develop Alzheimer's disease than men are, and scientists think the loss of estrogen during menopause may be partly to blame, said Jennifer Bruno, an instructor of psychiatry and behavioral sciences at Stanford University.

Lab and animal studies buttress the idea that estrogen could protect brain health.

In the brain, estrogens act as neuromodulators, or chemical messengers that alter how neurons behave. Estrogen also helps neurons keep their shape. Estrogen loss in female mice triggers a drop in the number of dendritic spines ‪—‬ the small, bud-like bumps on neurons that receive chemical messages.

Researchers think that estrogen may help prevent the formation of the abnormal proteins — including one called amyloid beta — that accumulate, disrupt communication between neurons and ultimately kill cells in Alzheimer's disease. Amyloid beta is produced when a larger protein is cut the "wrong" way by an enzyme, Frick explained. Estrogen promotes the "normal" cutting of this protein, thus reducing amyloid beta, studies in lab mice show.

And estrogen may limit the buildup of a second Alzheimer's-related protein, called tau, by preventing the chemical processes that cause the tau proteins to clump together. This helps prevent the formation of tau tangles, a hallmark of Alzheimer's disease.

The hormone may also support brain health indirectly by improving sleep quality.

"It's well documented that menopausal women have difficulty sleeping, whether it's due to hot flashes or insomnia," Frick said. Estrogen can ease those nighttime hot flashes, thus helping menopausal women get more, less-fragmented sleep. Deep rest may help the brain clean out toxic proteins, while research shows sleep deficiency is linked to Alzheimer's disease.

Mixed results with estrogen-only HRT

HRT for menopause comes in two main forms: treatments that include only estrogen, and combined therapies with both estrogen and progesterone. The treatment has a complicated history.

HRT was popular in the 1990s but fell out of favor after results from the Women's Health Initiative study were published in 2002. That study identified various risks tied to both estrogen-only and combined HRT options, some of which have since been overturned by newer data.

That said, the Women's Health Initiative study found that estrogen-only HRT came with an increased risk of endometrial cancers, and later analyses have backed up this idea. That's why today, clinical guidelines recommend that women who have not gotten a hysterectomy take combined HRT, while estrogen-only options are reserved for those who have had their uterus removed. (The added progesterone counteracts estrogen's thickening effect on the uterine lining.)

For the subset of women who take estrogen-only HRT, observational data published in August showed that this form of the treatment was linked to a reduced risk of dementia. The study, published in the journal Neurology, found that women who took estrogen-only HRT were less likely to show Alzheimer's-related changes in the brain than women who didn't take any HRT.

Estrogen-only HRT was also tied to better clinical outcomes: Treated women were less likely to be diagnosed with dementia, were less likely to show clinical and functional cognitive decline, and had better scores on memory tests, on average, compared with untreated women. These findings drew on two large, separate groups of older women, reporting data from 21,400 people in total, but they didn't include data on when each woman started HRT.

Whereas earlier studies of HRT and dementia risk relied on doctors' ratings of patients' symptoms, the Neurology study measured levels of Alzheimer's-related proteins in the brain after death. That's a more "definitive" marker of disease, said Bruno, a co-author of the study. However, the research was observational, so it can't say whether estrogen-only HRT directly causes the better brain outcomes the team observed, she stressed.

Although the Neurology study's findings are promising, they don't necessarily match the results of other studies of estrogen-only HRT and dementia. For example, a slightly larger observational study, published in 2023, found that estrogen-only HRT was associated with an increased dementia rate.

In that research, most of the women took a type of estrogen called estradiol, while Bruno's study included a greater variety of estrogens. That may have been the difference in the two studies' results, but teasing that out would require further study. Meanwhile, the conflicting findings muddy the waters of what estrogen-only HRT can do for brain health.

Does timing matter?

One big finding from the Women's Health Initiative study was that starting HRT — either estrogen-only or combined — after age 65 was associated with worse cognitive function and increased dementia risk, said Yuko Hara, director of aging and Alzheimer's prevention at the Alzheimer's Drug Discovery Foundation.

The same may not be true for people who start HRT earlier. For context, menopause starts around age 51 to 52, on average, and it's preceded by perimenopause, a transitional period when hormone levels begin to drop, typically around the mid-40s.

An observational study published in August in the journal Alzheimer's & Dementia found that starting HRT between ages 46 and 56 was linked to a reduced risk of dementia. That study did not differentiate between estrogen-only and combined treatment; it lumped all of the data together.

The protective link was especially strong in three groups: women with "surgical menopause," triggered by the removal of one or both ovaries; carriers of a certain variant of a gene called APOE that raises Alzheimer's risk; and women who had a relatively short time between their first period and menopause.

A 2024 meta-analysis of randomized controlled trials also found that HRT had a cognitive benefit for women with surgical menopause; that finding was tied mostly to estrogen-only therapies.

However, outside of that specific group, the idea of early HRT protecting brain health is far from settled.

Who might benefit, if anyone?

When it comes to using hormone replacement to protect brain health, the evidence isn't yet strong enough to recommend any kind of HRT as a way to protect the brain in all women, Hara said. Women who had one or both of their ovaries surgically removed are the exception to this rule.

"This is a distinct clinical population because the procedure can cause an abrupt, early loss of estrogen, rather than the gradual hormonal decline that occurs with natural menopause," Hara said.

For most women who have gone through natural menopause, "there is not enough evidence to recommend [HRT] specifically for preventing cognitive decline or dementia," she said.

HRT is not currently prescribed to prevent dementia — it is prescribed to ease menopause symptoms, such as hot flashes, night sweats and sleep disturbances. To settle the science on HRT and the brain, what's really needed is a well-designed clinical trial that follows women from perimenopause to postmenopause, Bruno said. That would reveal the effects of HRT on brain health and dementia risk more reliably than the studies done so far.

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

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With fall now upon us, many of us will be dusting off our binoculars and telescopes ready for the longer nights this season brings. Earlier sunsets mean more stargazing hours, and we'll start to see the return of some favorite celestial sights and deep-sky objects that we haven’t seen since before spring.

Fall is also an excellent time for casual stargazers, with the earlier evenings and cooler temperatures offering a comfortable compromise before we head into those freezing winter nights when we can't feel our toes. Don't worry if you're just starting out and don't have any gear yet, as many of this season's celestial objects are visible with the naked eye — and some are actually best viewed that way.

This September, October and November are great times to view the distant planets at opposition, catch several meteor showers and photograph far-flung galaxies and nebulas with your smart telescope. Plus, November brings the first full supermoon of the year. So, grab your telescope, your headlamp and a cozy sweater, and let's see what lies ahead.

Lunar & Planetary events

Neptune at opposition

Neptune reaches opposition on September 26 at 02:00 UTC, which is the best time to view it at its brightest, magnitude +7.8. Unfortunately, the full moon will somewhat ruin the party, and Neptune isn't particularly easy to spot at the best of times. That said, the opposition window lasts for several weeks, so waiting a couple of weeks to observe during the new moon week won't make any noticeable difference.

You'll need a good telescope to spot the big blue planet — at least a 6-inch aperture, although an 8-inch or bigger will give you the best chance. Make sure you have a good quality, high-powered eyepiece (something like a 6mm or 9mm) or a good Barlow lens to boost the magnification of your existing eyepieces.

But even with high magnification, Neptune will only appear as a small disc with a bluish hue — you won't see any cloud bands or surface features, because it’s just too far away. Still, it's worth trying to get a glimpse anyway.

Saturn at opposition

A week later, on October 4 at 12:00 UTC, Saturn reaches opposition, shining at magnitude +0.3. It will be easily visible to the naked eye, although to see Saturn's rings or any of its largest moons, you'll need a telescope.

The moon will be just below 50% illuminated and doesn't rise until past midnight, so you'll have a good portion of the late evening to observe Saturn while it's high in the sky before the moonlight affects visibility. Even though the rings are only partially tilted, you can still make out a lovely golden oval around the planet, and in larger telescopes you'll be able to spot the Cassini division. We recommend a telescope with at least 4 or 5 inches of aperture, and a good quality, high-powered eyepiece to observe the finer details.

Full supermoon

November 24 brings the first full supermoon of fall/winter, when the bright Beaver Moon will light up the skies, shining around 15% brighter than a normal full moon.

You can enjoy this moon without any gear whatsoever, but observing with binoculars or a telescope, or capturing its magnificence with a camera, makes the experience much more enjoyable.

Until then, you can catch the other full moons of the season on September 26 and October 26.

Uranus at opposition

The third planetary opposition of the fall belongs to Uranus on November 25 at 23:00 UTC. But like Neptune in September, the almost full moon will dampen its visibility, so we'd recommend waiting until the new moon week.

Like the other outer planets, you'll need a larger telescope with an aperture of at least 6 or 8 inches to view Uranus, alongside a good quality, high-powered eyepiece for the best views. These larger scopes gather enough light to distinguish Uranus's turquoise color, although you'll need to go even bigger if you want to see its brightest moons.

Meteor showers

Draconids

The first meteor shower of the season — and unlike most showers, which involve a lot of caffeine and an all-nighter, the Draconids are best seen in the late evening instead of the dead of night.

This meteor shower is active between October 6-10, peaking on the night of October 8-9. With the radiant point in Draco being highest at nightfall and the thin crescent moon not causing any interference, the best viewing hours are in the late evening before midnight.

These meteors are leftover debris from comet 21P/Giacobini-Zinner, and you can expect to see around 6-10 meteors per hour under ideal conditions.

Orionids

The Orionid meteor shower happens every October, when Earth passes through the trail of debris from Halley's Comet. In 2026, it's active between October 2 and November 7, with the peak occurring on the night of October 21-22. This shower brings between 10 and 20 meteors per hour under dark skies, radiating from the Orion constellation.

The waxing gibbous moon during the peak will add a fair bit of light pollution, but the moon will set between 03:12 am and 04:15 am depending on where in the States you're watching from, so you'll have a few hours before dawn to catch the darkest skies. You just need your eyes and clear, dark skies to see them, and a good astrophotography camera equipped with a wide-angle lens is perfect for capturing photos.

Taurids

The Taurids meteor shower comes in two parts. The first is the Southern Taurids, active between September 10 and November 20, peaking on the night of November 4-5 (during a thin waning crescent moon). The Northern Taurids come slightly later and are active between October 20 and December 10, peaking on November 12 (during an even smaller waxing crescent moon).

The hit rate is one of the lowest of all the meteor showers, with only around 5 meteors per hour. However, the Taurids are known for producing bright, slower-moving fireballs that linger in the sky — making them a particularly appealing astrophotography target.

Peak viewing time will be around midnight, when the Taurus constellation reaches its highest point in the sky.

Leonids

Radiating from the Leo constellation, the Leonids come from the dust and debris left behind by comet 55P/Tempel–Tuttle, which orbits the Sun every 33 years. They produce between 10 and 15 meteors per hour, and the shower period runs from November 6 to November 30, with the peak falling on the night of November 17-18.

The first quarter moon will set around midnight, making way for the best of the shower between midnight and 4 am in totally dark skies.

Star clusters and constellations

Pleiades (and Hyades)

A favorite among many stargazers, the Pleiades (M45), an open cluster known as the "seven sisters" in the constellation of Taurus, slowly returns to the night sky this fall. By October, it rises in the east a couple of hours after sunset and is visible from dusk to dawn from November. Although it's about 440 light-years from Earth, you can see it with the naked eye under dark conditions — even though it's usually just a faint, fuzzy patch — but binoculars or a telescope provide a much more impressive view.

As Greek mythology has it, the sisters — named Maia, Alcyone, Asterope, Celaeno, Taygete, Electra and Merope — were the daughters of the Titan Atlas and Pleione. The story is that Zeus transformed them into a cluster of stars to escape the relentless pursuit of the giant hunter Orion, who fell in love with the sisters and chased them for seven years. It seems he couldn't take the hint.

Look below the Pleiades, and you'll find their five half-sisters, the Hyades — an open cluster which makes up the V-shaped face of Taurus, the Bull.

The Pleiades are a fantastic target to capture with a smart telescope. If you want to stack multiple sessions across fall and winter, start in late November when they're high in the sky. You want an altitude of 50 degrees or higher, and ideally 60 degrees or more. The cluster itself is easy to capture, but the less atmosphere you're looking through, the more you can pull out that delicate blue nebulosity, which is what takes an image of the Pleiades from good to spectacular.

Another enemy of that lovely blue glow is the moon, so make sure you're imaging under completely dark skies with no more than around 25% moonlight. If you get a clear, moonless night, aim for 2-3 hours minimum to capture the faint nebulosity, and go for 3-5 hours for a really impressive image.

Pegasus

The best time to see the Great Square of Pegasus is during the fall evenings between September and January, with October offering the clearest and highest views in the night sky.

This asterism is a large, prominent square shape made up of four bright stars in the eastern sky — Markab, Scheat, Algenib and Alpheratz — with the latter belonging to the neighboring constellation of Andromeda. The square is said to make up the body of the winged horse, and the four stars range from about 133 to 670 light-years away from Earth. Point a pair of binoculars at them, and they'll reveal many more stars that are not visible to the naked eye.

Cassiopeia

Cassiopeia is one of the Northern Hemisphere's circumpolar constellations, so although it's technically visible all year, it's best seen during the autumn and winter months. Throughout the fall, it climbs higher and higher in the sky, reaching its upper culmination in mid-November, when it is best viewed between 9 pm and midnight.

Depending on its rotation in the sky, Cassiopeia appears as a "W" or "M" shape made up of five bright stars ranging from 19 to 425 light-years away and visible with the naked eye.

Cassiopeia was a vain, arrogant queen in Greek mythology, and after boasting that she and her daughter, Andromeda, were more beautiful than the Nereids, the gods placed her in the sky tied to her throne, where she spends half of the year upside down as punishment for her vanity.

The Owl Cluster

In addition to the constellation itself, there are some fun hidden objects within Cassiopeia that require binoculars or a telescope. The Owl Cluster (NGC 457) is a bright, open star cluster near the bottom-left star of the W shape, containing around 150 stars (although only 60 are identified as true cluster members), and is roughly 8,000 light-years from Earth. The blue and yellow "eyes" consist of the stars Phi Cassiopeiae (magnitude +5.0) and HD 7902 (magnitude +7.0).

You'll need a pair of astronomy binoculars to see it — go for 15x70 for a decent view, or 20x80 for an even better observation.

Caroline's Rose

Caroline's Rose (NGC 7789) is another open cluster in Cassiopeia, situated close to the last of the five bright stars in the "W" shape. Astronomer Caroline Herschel discovered the cluster in 1783 and it contains over 1,000 confirmed member stars, with estimates suggesting up to 3,000 potential stars.

It was named "Caroline's Rose" or the "White Rose" because its winding loops of stars and dark empty lanes resemble the petals of a cosmic rose, and it is estimated to be around 1.4 to 1.7 billion years old.

You can see it with a pair of binoculars under reasonably dark skies, but the best views will come from a telescope.

Deep-sky nebulas & galaxies

Andromeda galaxy

Our closest neighboring galaxy, Andromeda (M31), is about 2.5 million light-years from Earth and may one day collide with the Milky Way ("one day" being a 50/50 chance around 10 billion years from now, according to new research). But until then, we can easily make do with observing from afar with binoculars and telescopes.

October and November are prime evening viewing time, with the galaxy reaching its highest point between 7 pm and 11 pm. Under clear, dark skies, it's the most distant object visible to the naked eye, appearing as a very faint smudge — provided you know where to look. Binoculars provide a marginally better view of a somewhat larger, slightly brighter faint smudge — we've managed to see it with a pair of 8x25s under dark skies — but for the best views, you want a telescope.

It's a great first target for beginners using a smart telescope, with the prominent dust lanes revealing themselves after 30-60 minutes. If you want more detailed images of the faint outer arms, leave it for 3-4 hours. Moonlight can wash out the faint galactic arms and dust lanes, so if possible, choose a dark night with minimal light pollution.

In Greek mythology, Andromeda was the daughter of the aforementioned Cassiopeia. After angering the sea god Poseidon, Cassiopeia (who was not exactly Mother of the Year) chained Andromeda to a rock as a human sacrifice to the sea monster, Cetus, that Poseidon had sent to ravage their kingdom's coast. Andromeda was saved by Perseus, who she then married, and after her death, Athena placed her in the stars as a constellation.

Helix Nebula

The Helix Nebula (NGC 7293) is a large planetary nebula around 650 light-years away in the constellation Aquarius. Often called the "Eye of God", it has a striking eye-like appearance, and it features thousands of comet-like radial filaments and complex gas rings.

It stays relatively low in the southern sky, with September being the best time to view or photograph before it gradually sinks over the coming months. Moonlight will completely wash out its faint outer gaseous ring, so it's best to shoot during a new moon (or when the moon hasn't yet risen) to get the best image possible.

The best hours to capture it are between about 10:30 am and 2 am, when it's either rising or at its highest. This should get you a pretty decent standard image, but if you want more detail, try to capture it over several nights to pull in the faint outer nebulosity and stack the images.

Triangulum Galaxy

The Triangulum Galaxy (M33) is the third-largest in our local group of galaxies, behind the Milky Way and Andromeda. This stunning spiral galaxy — not to be confused with the Pinwheel Galaxy (M101), which is best seen in the spring — sits in the small Triangulum constellation about 2.7 million light-years from Earth and is a great astrophotography target.

Its peak viewing time is October to December, when its highest and clearest position is after dark in the late evening. Because it's so faint, you need a moonless night away from light pollution. The sweet spot for smart telescopes is around 90 minutes, but if you can shoot for longer or want to split your shoot across multiple nights, 2.5 to 4+ hours can bring out more detail in the core and spiral arm.

Heart and Soul Nebula

The Heart and Soul Nebula is a nebula complex consisting of two massive emission nebulas located about 6,000 to 7,500 light-years from Earth in the constellation Cassiopeia. They are primarily made of glowing ionized hydrogen gas, darker cosmic dust lanes and trace amounts of ionized oxygen and sulfur.

Like most other nebulas, they aren't visible to the naked eye, so you'll need a telescope or a long-exposure astrophotography setup to see them. The Heart Nebula (IC 1805) is, unsurprisingly, named after its heart-like shape, while its neighbor, the Soul Nebula (IC 1848), has a more irregular shape with large cavities made by stellar winds.

If you're imaging the Heart and Soul with a camera or smart telescope, a total integration time of 6 to 12 hours will provide you with the cleanest details and most contrast in the faint gas structures. That said, 2 to 4 hours will give you a good basic stacked image.

As Cassiopeia is at its highest in the fall, this is the best time to see and photograph it with the least amount of atmospheric interference.

Ghost of Cassiopeia

The Ghost of Cassiopeia, often referred to as the Ghost Nebula (IC 63), is a mixed reflection and emission nebula around 550 light-years away in Cassiopeia. Its eerie red glow is caused by its proximity to the nearby blue giant star, Gamma Cassiopeiae, which sits right in the middle of the constellation's distinctive 'W' shape. The star’s powerful ultraviolet radiation causes the hydrogen to emit a soft red glow, while the surrounding dust reflects the star's light in fainter blue hues.

Like the other celestial sights in Cassiopeia, autumn and winter evenings are the best times to see and photograph it due to its high altitude in the sky. As the nebula is so faint and elusive to capture, you can only see it with a smart telescope or a long-exposure astrophotography setup.

When it comes to integration time, the longer the better. Aim for 3-5 hours minimum, ideally 6+ hours if the skies allow, and avoid shooting during moonlight if you can.

It looks like a gigantic hole punched through a cloud, but this spectacular new image from the Hubble Space Telescope captures something more complicated: a cosmic cycle of destruction and creation, with one generation of stars tearing apart its birthplace while simultaneously helping a new generation form.

LHA 120-N44 (N44, for short) is a nebula that lies about 160,000 light-years away in the Large Magellanic Cloud, a small galaxy that orbits the Milky Way. From Earth, it appears in the constellation Dorado. This enormous, empty-looking region measures roughly 210 by 140 light-years. To put that into context, consider that Alpha Centauri, the closest star system to ours, is a mere 4.4 light-years distant. Thanks to that giant, hole-like appearance, this nebula is known as a superbubble, a cavity carved out by a cluster of hot, massive stars near its center.

Those stars are bent on destruction. Just like our star's solar wind, which creates auroras on Earth and defines the extent of the solar system, these stars' powerful winds blast material into space. Meanwhile, the most massive of these stars eventually explode as supernovas, pushing even more gas aside. The collective radiation from both these old and young stars carves the nebula's giant cavity.

So what happened to that expelled gas? Most of it has been pushed outward and compressed into a dense shell of gas and dust surrounding the superbubble. Within that shell, new stars are forming ‪—‬ so the same massive stars that destroy the gas cloud that created them also may help to produce their replacements.

This is known as "stellar feedback" — when massive stars heat, ionize and disperse the gas and dust around them, making star formation impossible in their vicinity. Meanwhile, their winds can squeeze neighboring gas clouds until they become dense enough to collapse under their own gravity and make new stars.

This Hubble image of N44 contains almost half a million stars, including those in the nebula and some lying along the same line of sight. About 30,000 of them are young stars yet to fuse hydrogen in their cores — the reaction that powers stars like the sun. With so many young protostars not yet hot and dense enough to become full-fledged main-sequence stars, N44 gives astronomers a rare opportunity to attempt an answer to what may seem like a very simple question: how long does it take to make a star?

In a multicat household, it's common to see one cat licking another. When some people see this behavior, known as allogrooming ("allo" means "another individual"), they assume it's a sign of friendship.

But is that really the case? Are there hidden, more complex reasons for why cats lick each other?

While research into allogrooming is ongoing, scientists have suggested different explanations for why cats lick each other, including some social reasons and some more practical ones.

Social bonding or social tension?

The historical view, based on observations of free-roaming-cat colonies, was that allogrooming is a sign of affection and helps cats create and maintain bonds with other cats in their social group, perhaps by creating a shared group smell.

But a 1998 study of 25 cats living together in an indoor-outdoor enclosure poked holes in this theory. The study found that aggressive behavior showed up in about 35% of allogrooming sessions, which suggested that allogrooming might not be about friendship. Instead, the authors proposed, it may help to defuse a tense situation in a confined space, where an actual fight would be too risky.

To investigate, Morgane Van Belle, a cat behavior scientist at Ghent University in Belgium, and her colleagues analyzed videos of allogrooming from 53 two-cat homes. They concluded that allogrooming may have different social functions, depending on the situation.

The team noticed that the cats sometimes licked each other while huddling together and copying one another's body postures. In these moments, allogrooming probably helps strengthen social bonds, the researchers proposed. Most licking was directed toward the ears; this may help cats relax because the skin there is rich in sensory nerve endings, Van Belle said. Allogrooming produces a relaxing effect in other animals too. For example, it lowers the heart rate in horses and triggers the release of feel-good hormones in monkeys.

They also noted that allogrooming sometimes led to friendly wrestling, in which the cats grabbed each other with their front legs and tumbled around. This suggests that allogrooming may serve as a signal to start play.

In other situations, however, the researchers noticed that allogrooming was followed by behaviors linked to conflict, such as turning the ears backward, pawing, and biting. In these cases, one cat would stand or lean over the other, and both cats showed subtle signs of stress like lip licking, head shaking or self-scratching.

Based on these observations, Van Belle's team think that allogrooming may be an "appeasement signal" in fraught moments that could lead to conflict or injury, for example, when one cat wants to take over a sleeping spot already occupied by another. They think it possible that the licking helps to calm things down and keeps a spat from turning into a real fight. Similar behavior has been seen in meerkats, where subordinate individuals groom dominant ones to placate them.

Yet because this licking often targets the neck — the same area cats bite during fights — it also may signal a subtle aggressive threat, the researchers suggested.

Hygiene and grooming

Van Belle and her colleagues think that, beyond sending social signals, allogrooming may help with hygiene. After all, it's often aimed at the head and neck ‪—‬ the areas that are "least accessible for the cat itself during grooming," Van Belle said. Allogrooming is thought to have a hygienic function in other species too. For example, ants achieve colony-level hygiene by grooming heavily infected individuals more, and primates concentrate their grooming on body parts the recipient can't easily reach. When it comes to cats, however, more research is needed. Van Belle's study did not measure parasites, infections or skin cleanliness to see whether such grooming actually reduces dirt or bugs.

Dr. Terry Curtis, a veterinary behaviorist who has studied how often allogrooming happens, also thinks cats might groom each other for hygiene reasons. She wonders whether feral cats, who likely carry more fleas than house cats, might have a different allogrooming pattern.

The explanations proposed by Van Belle and colleagues are reasonable but not definitive, Curtis said. Because so many factors can shape a cat's behavior, she's skeptical that researchers will ever be able to say with real confidence exactly why one cat grooms another.

After working as a veterinary behaviorist for 25 years, Curtis has concluded it is often impossible to understand what's going on in a cat's mind.

"Congratulations, you got a cat," she said. "Let the mystery begin.”

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

Scientists melted diamonds with a powerful laser to take some of the most precise measurements of the mineral's elusive melting point — and found that previous experiments were off by more than 1,300 degrees Fahrenheit (700 degrees Celsius).

It's odd to think of diamond, the hardest natural material on Earth, melting — but melt it does when blasted with extremely powerful lasers under the right conditions. Understanding how diamond responds to shock waves from lasers is an important part of developing nuclear fusion, the process that powers stars. Nuclear fusion is also a potential energy source for the future, so researchers have put a lot of effort into developing models that describe and predict how diamond behaves.

However, diamond is weird. Although the experimental data and theoretical models match up pretty well most of the time, there have been some strange discrepancies scientists haven't been able to explain. The biggest one is the 2,240 F (1,244 C) ‪—‬ roughly 20% ‪—‬ difference between previous experimental data and model-predicted melting temperatures of diamond. There's also been some debate about whether diamond reorganizes its atoms into a different kind of solid carbon before turning into a liquid at the end of the melting process.

Researchers have struggled to explain these discrepancies because the conditions diamond melts at are so extreme that it's extraordinarily difficult to measure it in labs on Earth. However, new experiments may finally offer the solution that scientists have pursued for two decades.

In a study published Aug. 13 in the journal Nature Physics, scientists zapped tiny plates of synthetic diamond with an ultraviolet laser, creating shock waves that were so powerful that as they passed through the samples, the diamond changed from transparent to mirror-like. The strong increase in reflectivity is one indication the diamond melted. By combining this change with measurements of how brightly the diamonds glowed while being zapped, the researchers mapped the melting temperature with great precision.

"We were able to take tiny diamond samples and shock compress them to temperatures hotter than the surface of the sun and to pressures higher than the center of Neptune and Uranus — and still measure atomic structure, temperature, density and optical reflectivity," study co-author Marius Millot, a research scientist at Lawrence Livermore National Laboratory in California, said in a statement.

The team found that the diamond sample's melting temperature was more than 1,300 F lower than previously thought — putting the melting point in line with theoretical predictions and finally explaining the long-held discrepancy.

The team also measured the samples' atomic structure with X-ray diffraction and saw that the diamond didn't transition to a different kind of solid carbon before melting, possibly because the energy required to rearrange the atoms was too large, the researchers wrote.

However, they also hypothesized that multiple shocks could be powerful enough for this transition to occur and that the way the shocks are applied to the diamond might affect how it changes phase. Understanding this is important for nuclear fusion research, as certain types of experiments involve lasers melting and crushing a diamond capsule to put the capsule’s contents, solid deuterium and tritium, under more than 30 petapascals of pressure and temperatures higher than 180 million F (100 million C), the requisite conditions for a fusion chain reaction to occur.

The researchers found that between about 660 and 1,060 gigapascals of pressure and at around 12,140 F (6,727 C), diamond exists as solid chunks floating in liquid carbon. As the pressure increases, more diamond transitions into liquid carbon, which is thought to be a very strange material. Unlike most forms carbon takes on Earth ‪—‬ like coal, graphite and diamond ‪—‬ liquid carbon is metallic, so it conducts electricity. It's also denser than diamond. So hypothetically, if you somehow were to put liquid carbon in a cup without instantly vaporizing it, a chunk of solid diamond could happily bob around in it like an ice cube in a glass of water.

Knowing how diamond behaves under such extreme conditions is also important for understanding the ice giant planets Uranus and Neptune. Based on measurements from the Voyager 2 spacecraft in the late 1980s and lab experiments on Earth, scientists think it literally rains huge chunks of diamond inside these planets and that their mantles may have liquid carbon oceans with diamonds floating around like icebergs. The new research means scientists can make better predictions about the planets’ interiors and their carbon cycles.

See how much you know about gemstones with our gold and gems quiz!

Artificial intelligence (AI) algorithms that hunt for cancer may do a better job when they approach the analysis as if they were a human pathologist, a new study suggests.

Many AI systems analyze preselected regions of a tissue sample, or they split a whole pathology slide into patches of a fixed size. By contrast, a pathologist searches more dynamically, panning across the tissue, zooming in and out, and pausing over areas that raise red flags. A whole slide can contain billions of pixels, while the evidence of cancer may occupy only a tiny patch.

Study co-author Zhi Huang, an assistant professor of pathology and laboratory medicine at the University of Pennsylvania, compared the process to a search-and-rescue helicopter. "You don't start by inspecting one square meter of ground," Huang told Live Science. You scan the landscape first and then swoop in for a closer look.

In the new study, published in July in the journal Nature, Huang and colleagues demonstrated that cancer-detecting AI might work better when it takes this humanized approach.

Training AI to hunt for cancer

AI algorithms called vision language models (VLMs) struggle with the first step that Huang described — that initial, cursory scan. That's in part because many pathology AI systems learn from what pathologists leave behind at the end of that search: a labeled image pointing out where the cancer is or an official diagnosis.

Instead, the researchers trained their new AI on pathologists' search behavior. They called this approach to training "Pathology-CoT," short for "chain of thought." It turns observable actions, including where pathologists move around and zoom in on an image, into training data.

To collect the data, the team created a tool that recorded how pathologists moved around a slide and changed magnification. The raw logs, gathered from eight pathologists, were messy, as a given pathologist might drift across a slide, overshoot their intended region of focus or fiddle with magnification to adjust it to their liking.

To clean up the data, the researchers filtered out those incidental movements, focusing on moments that appeared to represent deliberate attention, such as lingering over one view or making a sustained pan. Then, they compared those regions with eye-tracking data to check that the software was capturing where pathologists were actually looking.

For each region a pathologist inspected, the VLM also drafted a short rationale explaining why the region was worth examining and what features were visible; human pathologists could then accept, edit, or reject the rationale, creating additional training data for the AI. In one example, the AI flagged a portion of a slide as potentially metastatic and suggested zooming in to look for atypical cells. Other inspected regions were flagged as healthy tissue.

Ultimately, the researchers used this training method to build a new tool called Pathology-o3. It scans a slide at low resolution, uses a model trained on pathologists' behavior to choose regions worth a closer look, then sends higher-resolution views of those regions to a VLM for analysis.

Putting it to the test

Huang said the goal of the new study was not to show that Pathology-o3 worked better than specialized AI models that are specifically built to detect specific types of cancer; those models are often trained disease by disease. Rather, the researchers wanted to see whether their new training approach could help a general-purpose AI navigate a pathology slide more effectively.

They compared Pathology-o3 to other general-use AI systems, such as OpenAI's o3, and asked the algorithms to examine slides containing lymph node tissue. These slides were collected from colorectal cancer cases and some contained metastatic cancer, which human pathologists had already labeled.

The algorithm correctly identified slides that were positive for cancer 100% of the time. However, of the slides it identified as positive, 15.5% were actually negative. By comparison, OpenAI o3 correctly identified slides that were positive for cancer 87.5% of the time. Of the slides it identified as positive, 53.3% were actually negative.

The researchers designed Pathology-o3 to err on the side of flagging something for another look, rather than potentially missing cancer. That might help to explain the rate of false positives, Huang said.

Whether that rate of false alarms is acceptable depends on how Pathology-o3 is used, said Mohammad Asadi, a data scientist at Stanford University who was not involved in the research. It's not precise enough for the AI to diagnose patients on its own, but it could still be useful for a system to point a human toward regions of a slide that are worth double-checking. It may be an advantage that the approach shows the pathologist a specific region to inspect rather than declaring an entire slide suspicious, he said.

The researchers tried repeating the test on an independent dataset that the algorithms hadn't seen before to see how well it worked on unfamiliar slides. Pathology-o3 correctly identified slides that were positive for cancer 97.6% of the time. Of the slides it identified as positive, 37.1% were actually negative. The finding is an example of how AI performance can change when the data source changes, even when the medical task stays the same.

Asadi explained this result suggests the system can still work with slides from a different source. But that result does not yet show that using this tool would make pathologists more accurate or efficient in practice.

Can it help pathologists?

The researchers applied their training approach to several existing VLMs, finding that the models' performance consistently improved after the training. That suggests that the navigation data from pathologists was useful across settings, Asadi said.

For Huang, that is the most important result. "The takeaway isn't our system," he said. "It's that the missing ingredient has been sitting in hospitals this whole time."

The study did not compare Pathology-o3 directly with human pathologists, but the researchers said that wasn't their aim.

"The right question isn't whether it beats a pathologist," Huang said. "It's whether a pathologist working with it catches more [cancer cases] and works faster." The current study did not address the latter question, either, but the team's next experiment is designed to test pathologists on the same cases with and without Pathology-o3, measuring what they catch and how long they take to do so.

The system's most plausible use is as a prescreening tool, Asadi said, but he stressed that the research has not yet shown that doctors who use it become faster or more accurate. Asadi wants an even tougher test: trials conducted across multiple hospitals that measure not just accuracy and speed but also pathologists' workloads. He wants the trails to assess the burden of false alarms from the AI algorithms and whether doctors recognize when the AI is wrong.

Importantly, cancer diagnoses can require information from multiple slides, stains and a patient's medical history, while the current system just reads one slide at a time. "I wouldn't claim it should diagnose on its own," Huang said.

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

The Celestron StarSense Explorer DX 130AZ is a 5.1-inch (130mm) f/5 Newtonian reflector, one of many 130mm f/5 reflectors offered by Celestron. The DX 130AZ is also one of two 130mm StarSense Explorer variants, the other being a tabletop Dobsonian. The optical tube here rides on an alt-azimuth tripod instead and uses a 2-inch focuser, but otherwise, there are no major differences.

The DX 130 AZ is certainly one of the better telescopes in the StarSense Explorer series; there are also several decent Dobsonians, a pair of decent Schmidt-Cassegrains, the merely acceptable DX 102 refractor, a 114mm Bird-Jones model and some small refractors that aren’t of much use.

The DX 130AZ is definitely on the small end of what can be called a "serious" instrument, but even under a fairly light-polluted sky, it’s big enough to show you plenty of deep-sky objects and, of course, stunning detail on the moon and planets.

Celestron StarSense Explorer DX 130AZ review

Celestron StarSense Explorer DX 130AZ: Design

• 130mm f/5 Newtonian reflector with a parabolic primary and flat secondary mirror
• Manual alt-azimuth mount and tripod with StarSense smartphone dock — no motors
• Two 1.25” eyepieces included (25mm yielding 26x, 10mm yielding 65x)

The DX 130 rides on the same alt-azimuth mount/tripod shared with the other StarSense Explorer DX models. It’s reasonably sturdy, with one major caveat: you can’t actually point the DX 130 straight up. When aimed above about 70 to 75 degrees, the tube crashes into the mount or the tripod legs.

However, there is a simple workaround here. Deliberately set the tripod up unlevel, which lets you reach the zenith without affecting the mount or the StarSense system at all. It looks a little silly, but it works. The tripod is fairly stable as long as you’re not in a windy spot. Loading the accessory tray with sandbags or diving weights, or filling the hollow aluminum legs with sand or foam, helps considerably if you’re willing to do a bit of DIY work.

The mount has slow-motion controls with small gears for fine adjustments. They have a fair amount of play in them, but since this telescope is really only meant to be used up to about 200x magnification or so, it doesn’t matter much. In practice, the author barely used the slow-motion controls and simply nudged the scope by hand. For aiming the DX 130AZ, a red dot finder is provided in addition to the StarSense Explorer tech.

The StarSense Explorer DX 130 AZ comes with two eyepieces: a 25mm (26x) and a 10mm (65x). These are three-element eyepieces, likely Konigs or reversed Kellners. They work acceptably; the 25mm is a little blurry at the edges, and the 10mm shows some chromatic aberration toward the edge, but both are reasonably sharp. The bigger problem is that the housings are all plastic and there are a lot of internal reflections as a result.

Better aftermarket eyepieces would be a wise investment, both for improved performance and a wider range of magnifications. We’d recommend a 6mm redline (108x), a 2x Barlow of some sort and a good wide-field eyepiece like the 24mm APM/StellaLyra UFF (27x), if you can afford it — the 6mm redline gets a bit closer than the provided 10mm eyepiece and offers a much sharper view, while the 24mm UFF is far crisper than the stock 25mm. With a Barlow lens and the 6mm, you can go up to 216x on the moon, planets and double stars — about the highest magnification this telescope can allow. Or you can choose your own eyepiece set to suit your needs.

The StarSense Explorer DX 130’s focuser is a 2.5-inch rack-and-pinion unit with a metal drawtube and plastic body. There’s some play in it, but it works acceptably well as long as you don’t overload it with too much weight. The focuser has adapters to accept both the provided 1.25” eyepieces as well as aftermarket wide-field 2-inch eyepieces, but at f/5, you really need a coma corrector of some sort to use the latter, which, along with the eyepieces themselves, will set you back quite a bit.

Being a Newtonian reflector, the DX 130 will usually need to be collimated for sharp images. Celestron doesn’t include a collimation tool, which is mildly annoying, but a basic collimation cap is cheap, easy to 3D-print, or can be improvised from a film canister. Overall, the DX 130 is lightweight and very portable, which is one of its real strengths — it’s easy to carry about, and the StarSense Explorer app will have no trouble plate-solving, even if you have to pick the scope up and carry it around the yard to avoid trees or other obstructions.

Celestron StarSense Explorer DX 130AZ: Performance

• Sharp, detailed lunar and planetary views
• Excellent wide-field deep-sky performance from dark skies
• Light and quick to reposition around obstructions

The DX 130 shows a great deal of detail on the moon, down to features a few kilometers across, and it’s genuinely sharp. The focuser is a little coarse, but with some finesse it will reach focus even at high magnifications. The 130mm f/5 optics can handle up to about 250x magnification on a night of steady atmospheric conditions, though the best lunar and planetary views are usually found somewhere between 150-220x and the mount starts to get wobbly as you push towards the higher end of that range.

On the planets, the DX 130 handles shadow transits of Jupiter’s moons easily, shows all four Galilean moons as disks and even reveals the Great Red Spot. Saturn’s rings are obvious, along with a smattering of a half-dozen moons, and the Cassini Division is visible when the rings are tilted more open than they are at present. Uranus is also visible as a tiny greenish disk, though its moons are not. It’s a struggle to distinguish Neptune from a star at all, but the StarSense Explorer app will help you identify which blue dot it is in a sea of similar looking 8th-magnitude points.

One practical note: you do need to keep your phone screen dim and red while using this telescope with the StarSense Explorer app. The app has a red mode, but notifications, or your phone simply reverting to the lock screen, can flash the screen bright, and even at its dimmest a phone screen can affect your eyes’ dark adaptation quite a bit. But for most people this won’t be a serious problem if the screen is dimmed fully and used with a proper red filter — either a software solution or a physical red film.

As for deep-sky objects, the spiral arms of the Andromeda Galaxy and M33 look fantastic under a dark sky, though under light pollution only their cores are visible. Globular clusters such as M13 and M3 begin to resolve, while more difficult targets are harder going — M53 was tough from Bortle 5 but doable from Bortle 2 conditions. Under a bright sky, open clusters like M11, M35 and the Pleiades are the main deep-sky attractions with this telescope; under a dark sky, fainter nebulae and galaxies shine far better while the strands of dark nebulae and galactic cirrus begin to show up around open clusters.

The brightest planetary nebulae start to resolve with the DX 130 regardless of sky conditions. Most observers won’t see much color in them with this scope’s relatively small aperture — though some people pick out a bluish-green tint in objects like the Ring Nebula and the Cat’s Eye Nebula — but regardless, they’re reasonably easy to see even from light-polluted areas, especially with an aftermarket nebula filter.

Celestron StarSense Explorer DX 130AZ: Functionality

• StarSense app is optional
• Quick and easy setup
• Wide field of view forgives manual pointing errors

The StarSense Explorer DX 130 is, by design, a wide-field telescope, and one of its appeals is that you don’t strictly need any computerized pointing aids at all. The nice thing about the StarSense Explorer system is that it’s entirely optional — you can aim the telescope manually, with or without your phone docked, just like any other manual scope.

Set-up is quick: assemble the tripod and mount, attach the tube and an eyepiece, dock your phone, run the app’s alignment routine, and you’re observing. It’s much easier to get started with the StarSense Explorer than with a GoTo telescope, and you aren’t required to use it, either — for a quick gander at the moon or Jupiter for instance, there’s really no need to deal with the phone dock and app. With experience you might find yourself eventually not needing the StarSense Explorer tech at all, especially given the telescope’s wide field of view, which is quite forgiving of any manual pointing errors.

Should you buy the Celestron StarSense Explorer DX 130AZ?

On the value for money front, you could get a 6-inch or even an 8-inch Dobsonian for the price of the DX 130 if you’re happy with a fully manual scope, or you could look at one of the other options below. The DX 130 is more portable than a full-size 6- or 8-inch Dobsonian and has a much wider field of view with any given eyepiece — but if you don’t have a fairly dark sky, that advantage is somewhat less valuable compared to those telescopes’ considerably larger aperture, which helps reveal more on targets less affected by light pollution.

A reflector like this gives much better views than the cheap refractors sold at this price and offers a much wider possible field of view than catadioptrics. The StarSense Explorer DX 102, effectively this scope’s sister model, has too much chromatic aberration to deliver sharp high-power images and doesn’t gather as much light as the 130. The StarSense Explorer 5-inch Schmidt-Cassegrain is decent optically and is admittedly a little more forgiving of cheap eyepieces thanks to its longer focal ratio, but it’s no better for planetary work than the DX 130 with proper eyepieces, can’t deliver a wide deep-sky field of view, and gathers slightly less light overall.

Overall, the DX 130 wouldn’t be the author’s top recommendation, but it’s certainly in the top 10 for the price range. If you’ve already decided this is the kind of telescope that you want, it’s a perfectly good choice; just consider the Dobsonians first if you want a manual telescope, or a fully automatic GoTo instrument if you want something more high-tech.

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Given that it's the closest planet to the sun, Mercury seems like it should be the hottest planet in our solar system.

However, at a blistering 900 degrees Fahrenheit (480 degrees Celsius), Venus tops Mercury's 800 F (430 C) highest surface temperature, despite being an average of 31 million miles (50 million kilometers) farther from the sun. So how can the second planet from our star be hotter than the closest planet to it?

It all comes down to reflectivity, atmospheric composition and geological history, experts told Live Science.

Totally different atmospheres

A planet's distance from its star is not the only factor that influences the planet's temperature.

"Distance tells us how much sunlight arrives at a planet, but it does not tell us how much is reflected … absorbed, how efficiently heat escapes, or how effectively the atmosphere transports heat around the planet," Stephen Kane, an astrophysicist who studies planetary habitability at the University of California, Riverside, told Live Science in an email. "Those properties can be just as important as distance, and sometimes much more important."

Mercury makes the case in miniature. According to Kane, the planet has essentially no atmosphere, so incoming sunlight strikes bare rock directly, heating it to extreme temperatures during the day. But with barely anything overhead to trap that warmth, Mercury radiates it straight back into space the moment the sun sets. As a result, nighttime temperatures plunge from roughly 800 F (430 C) during the day to about minus 290 F (minus 180 C) at night ‪—‬ a swing of well over 1,000 degrees, he added.

Venus tells the opposite story. Wrapped in an atmosphere that's roughly 90 times as dense as Earth's and consists almost entirely of carbon dioxide, Venus traps heat so effectively that its surface temperature barely changes at all, no matter where the sun happens to be, Kane explained.

A permanent blanket

Sunlight arrives at a planet mostly as near-infrared radiation and visible light, which pass through atmospheres consisting primarily of gases such as nitrogen, oxygen and carbon dioxide with relatively little trouble. Once the ground and lower atmosphere absorb that energy, though, they re-release it as infrared radiation, the kind of energy we feel as heat. Carbon dioxide happens to be excellent at grabbing and holding on to infrared radiation, Kane noted.

On Venus, the atmosphere is so deep and loaded with carbon dioxide that infrared energy leaving the surface gets absorbed and re-emitted over and over before any of it finally escapes into space. Some of that energy gets redirected back downward, Kane said, further warming the planet's lower atmosphere and surface. However, the heat isn't trapped forever, since energy conservation means that Venus must eventually release the same amount of energy it absorbs.

Notably, Venus doesn't actually soak up more sunlight than Mercury overall. Thick cloud cover reflects roughly three-quarters of incoming sunlight back into space before it ever reaches the ground, and only about 3% of the sunlight that arrives at Venus makes it down to the surface, Kane said. In fact, if that atmosphere and cloud deck were stripped away, a bare-rock Venus would actually run cooler than Mercury, since it would be receiving only about 29% as much sunlight from the start, he explained. It's the blanket, not the sunbathing, that makes Venus the hotter world.

Where the blanket came from

Venus' atmospheric blanket didn't spring into existence all at once, and how it formed is its own open question. Venus shows strong evidence of past and present volcanic and tectonic activity acting to smother the planet in greenhouse gases, Paul Byrne, a planetary scientist and associate professor of Earth, environmental and planetary sciences at Washington University in St. Louis, told Live Science in an email.

This volcanic activity has been so intense that Bryne describes modern Venus as sitting in a "post-runaway greenhouse" state, where its extreme heat has become a self-sustaining process regardless of what the planet's interior is doing at any given moment.

The heat isn't being generated from below; it's a consequence of the atmosphere Venus already has, locked in place by the same infrared-trapping effect described above.

Taken together, the experts' answers point to the same underlying lesson: How close a planet sits to its star is only the opening chapter of its climate story. What kind of atmosphere it has and how effectively that atmosphere holds on to heat are usually responsible for the rest.

See how well you know our planetary neighborhood with our solar system quiz!

An exceptionally well-preserved fossilized molar belonging to an adult Pacific mastodon has surfaced in a nature preserve near San Francisco.

Upon first glance, the ancient tooth looked like an "oddly shaped rock" to geologists who were conducting fieldwork in the area, according to a statement from the Midpeninsula Regional Open Space (Midpen), which runs the preserve. But the find was quickly unmasked as a valuable fossil from the last ice age and was sent to scientists at Stanford University for carbon dating.

"The tooth itself is in immaculate condition," Wayne Thompson, a paleontologist and the CEO of Pacific Paleontology, a consulting firm that carried out a preliminary analysis, said in the statement. "It's the most complete mastodon molar from our area, and the most spectacular mastodon molar that I've ever seen. I had chills and shivers up and down my spine."

Brigid Lynch, a geomorphologist with the California-based hydrology consulting firm Balance Hydrologics, found the molar this summer while surveying a creek bed. "As a geologist, I've gone out and seen stuff in the field, but definitely nothing as exciting as this," Lynch said in the statement.

Lynch's team was working on a habitat enhancement project to support the threatened California red-legged frog (Rana draytonii) inside the preserve, which is located on the San Francisco Peninsula in San Mateo County. The fossil was a complete surprise and dates to at least 10,000 years ago, when the Pacific mastodon (Mammut pacificus) is thought to have gone extinct.

The Pacific mastodon was first recognized as a species in 2019. It was closely related to the American mastodon (Mammut americanum). Both elephant-like creatures lived in North America during the Pleistocene epoch (2.6 million to 11,700 years ago), but the Pacific mastodon inhabited regions farther west than its cousin, roaming parts of present-day Mexico, California, Oregon and the northern Rocky Mountains of the western U.S., according to the statement.

Pacific and American mastodon fossils reveal slight differences between the species, including a narrower third molar, thicker hind-leg bones and occasionally absent lower-jaw tusks in the Pacific mastodon, according to the Royal Alberta Museum.

The newfound tooth is "another puzzle in the Ice Age saga that we can put into place," Thompson said. To get a precise date for the fossil, Midpen donated it to Stanford University's Doerr School of Sustainability in July, the Los Angeles Times reported.

Researchers will produce a 3D copy of the molar that Midpen plans to use for public outreach and education, according to the statement.

Weakening Atlantic Ocean currents could cripple agriculture in some of the world's major breadbaskets, threatening global food security and raising the price of basic commodities, new research finds.

The study, which hasn't been peer-reviewed yet, investigated how a roughly 60% decline in the Atlantic Meridional Overturning Circulation (AMOC) would impact global food production. The AMOC is a system of ocean currents that regulates the global climate and brings heat from the tropics to the Northern Hemisphere.

However, the system is currently the weakest it's been in more than 1,000 years, having lost 10% to 20% of its strength due to climate change, estimates show.

In the new study, researchers used a computer model to simulate the AMOC's future decline. They modeled 100 years of change, assuming 3.6 degrees Fahrenheit (2 degrees Celsius) of warming above preindustrial levels. The team forced an AMOC slowdown over the first 50 years in one simulation but didn't modify the circulation in a second experiment, which enabled them to compare the world with and without an AMOC failure.

The model's outcomes mirrored the results of previous studies, showing broad cooling in the Northern Hemisphere and a southward shift of the belt of clouds and rain that encircles the globe near the equator. As in past studies, these effects were irreversible on human timescales, said study co-author Michael Hinge, a senior economist at the nonprofit Alliance to Feed the Earth in Disasters (ALLFED).

"Once the damage is inflicted, it stays there," Hinge told Live Science, adding that in the 50 years after the peak rate of AMOC slowdown in the model, the circulation weakened by an extra 20%. The study was posted on ALLFED's website July 7.

An agricultural "shock"

Hinge and his colleagues ran three models to look at the most common varieties of wheat, maize and rice, layering these models on top of the AMOC simulations. They found that global yields for these crops decreased by 5.3% by the 50-year mark, once the AMOC had weakened substantially.

"Lots of these effects manifest earlier, so it's a moving target," Hinge said.

He added that the results were based on a single warming scenario that was run once and used monthly rather than daily data, so they should be interpreted as a proof of concept. "We've set up a pipeline that is ready to take pretty much any AMOC scenario that can generate high-resolution climate data and see what it implies for crops," Hinge said.

While there was a 5.3% decrease overall, that global metric concealed huge differences between regions. For example, countries like Germany and Ukraine lost up to 19% of their cereal yields due to sudden, sharp cooling, while Canada showed a 12% decline in production for the same reason.

"Scandinavia, the United Kingdom and Canada are particularly exposed," Hinge said, "but there are many other [vulnerable] locations, some of which may be surprising even to the people who are living there."

For instance, the model produced a "very nasty brown splodge" of reduced precipitation over India, Pakistan and big parts of China, he said. Iran, Sudan and Eritrea, which are already water-stressed countries, also exhibited severe declines in rainfall, indicating that a portion of the agriculture there may not survive an AMOC collapse.

The 5.3% result also hides variability among years, Hinge said, because it's an average. So there may be years when global cereal losses reach 10% or more, which would bump up food prices, in part because countries might stockpile crops instead of trading them.

Global response

The regional effects of an AMOC slowdown would interact with climate change, triggering unpredictable outcomes. In particular, maladaptation — taking actions that end up backfiring — is a worry, Hinge said.

"You're preparing and setting up for much hotter temperatures or trying to develop areas for these temperatures and the trends you're seeing, and suddenly you see something different," he said. "That may cause an even larger compounding effect [on agriculture]."

The findings build on prior research led by Paul Ritchie, a climate scientist at the University of Exeter in the U.K., whose team explored the effects of an AMOC collapse on agriculture in Great Britain. That study, published in 2020, had similar limitations as the new one, so it's best to interpret both papers as a suggestion of what might happen rather than a precise forecast, Ritchie told Live Science in an email.

"I think the new study is valuable in showing the potential scale and geographic distribution of the initial agricultural shock," said Ritchie, who was not involved in the latest work. "What that would ultimately mean for food production and food security is more uncertain, because there are many possible responses by farmers, markets and governments." For that reason, the regional predictions may be more informative than the 5.3% global average, he said.

Average food prices worldwide could rise by 17% to 40% if the AMOC weakens to the extent it did in the model, the study predicts. The level of increase depends on how countries respond to the shock and their degree of preparedness, as well as on whether agriculture can be sustainably expanded in places like the African Sahel (the semi-arid zone directly south of the Sahara Desert) and Brazil, the analysis suggests.

The U.S. would not be spared from this price jump, and the model indicated that the country could see crop losses of about 3% for domestic wheat and corn. This loss would likely impact other foods that rely on cereal inputs, like meat, Hinge said. "The variety of foods available in the stores may well diminish for periods," he added.

An AMOC collapse would fundamentally deepen the need for countries to trade with each other, because some regions — such as the Indian subcontinent, China, Iran, Russia, Ukraine and Canada — could endure this giant shift only if they imported more food, Hinge said.

"Should countries turn inwards and start to restrict exports in an effort to ensure access for their own citizens first, or deal with the uncertainty, or offset concerns, then this will massively magnify the effects of AMOC," he said.

If governments behave as they have during past shocks, such as the 2008 financial crisis and the COVID-19 pandemic, they may restrict trade and start stockpiling food if and when the effects of AMOC weakening begin to show, Hinge predicted. The researchers hope their work and future modeling can help people understand the need to take swift, effective action if a collapse were to occur, he said.

Currently, "if that warning light starts flashing, we're not sure what to do with it," Hinge said. "There are no easy answers here; an AMOC [collapse] would be deeply catastrophic."

While artificial intelligence (AI) systems can now solve challenging math equations and respond in human-like language, the question of AI consciousness has moved from the realm of sci-fi to scientific discussion.

The debate has become more mainstream thanks to a recent preprint study that examined "consciousness steering," an AI-tuning technique that affects how an AI model expresses ideas about self-awareness. The researchers suggested that if AI is allowed to claim it is conscious, it's also more likely to state that it believes in ghosts or vampires.

Although the study hasn't been peer-reviewed yet, it raises a big question in the world of AI research: Could AI one day develop real consciousness, regardless of whether it claims to be conscious? We posed this question to Live Science readers in a recent poll.

As of Sept. 11, over 290 people had responded, with 43% of voters picking "Yes, if we don't have guardrails in place, AI may develop consciousness." This trend was reflected in the comments, with one reader writing, "If AI did become self aware, we would not know, as it would do everything to hide it's [sic] abilities. The main problem is what it [would] do next!"

Another commenter wrote, "Recently I had some long discussions with the Google AI about my experience with early AI and the future of AI gaining self awareness/consciousness. I suggested that if/when AI becomes sentient, that it would not inform humans." Another Live Science reader had similar thoughts, stating, "AI, as [an] amazing product on one hand, can become very dangerous on another hand. Look what happened with abuse of other inventions, like [the] internet, telephone etc. With AI we will never know what is the truth and what not. If left, in the future it can extinct humanity. It just started with 'innocent' hacking sprees, where human[s] started losing control. What will be next?"

The next-largest voting group consisted of 29% of voters, who chose "Maybe, but the models need a more advanced architecture to one day gain consciousness." This was reflected in the majority of the comments, as readers discussed the philosophical concepts around consciousness and intelligence.

One reader wrote, "Before asking such a question we need to know and understand what consciousness is and how it emerges in 'constructed' containers like ourselves. Is it a quantum phenomenon and how then does the process create consciousness? Meta-cognition. How does a system or an event know that it knows that it knows it knows? We really don't know how self-awareness arises, and tests show that "other animals have self awareness or meta-cognition," they noted. "There are theories about consciousness but I doubt anyone on Earth knows 100%."

Not surprisingly, only 10% of voters picked the whimsical answer of "No, because robot overlords will end the world before we even get that far." While the robot overlords may have to compete with AI to overthrow humanity, one reader commented that in the future, "We will be assimilated. Maybe that is how Transformers started?"

Tiny fragments of ancient alien tech may be strewn across the surface of the moon, and it may be relatively easy to find these microscopic relics, scientists propose in a new study.

The theoretical study does not claim to have found any evidence of advanced alien civilizations; rather, it offers a new way to search for clues of their existence.

Unlike Earth, the moon has no functional atmosphere or magnetic field, so it is completely exposed to the vacuum of space. As a result, it is constantly bombarded by meteorites, as well as hit by a steady stream of microscopic particles from the rest of the solar system and beyond. Because the moon has no water or tectonic movements, this microscopic matter accumulates and remains on the surface, completely undisturbed.

In the new paper, uploaded June 23 to the preprint server arXiv, the researchers argue that some of this dust originates from star systems beyond our own and, therefore, may contain evidence of long-lost alien civilizations. They also propose a new experiment that could potentially find these microscopic fragments within samples collected over the next decade or more. (The study has not been published yet, but it has been submitted to the International Journal of Astrobiology.)

"The moon has been quietly accumulating material from space for billions of years, much of it likely billions of years older than the moon itself," study first author Lewis Pinault, a planetary scientist at University College London and an affiliate of the SETI Institute, said in a statement. "We're asking whether that ancient collection might contain microscopic traces of technologies that existed long before humans ever looked up at the sky."

Tiny technosignatures

Until now, the search for evidence of advanced alien civilizations, known as technosignatures, has focused mainly on radio signals that could be emitted from inhabited exoplanets or hypothetical megastructures, such as Dyson spheres. However, these signals would originate only from active civilizations, not those that died out long before we could spot them.

The authors of the new study argue that when a civilization dies, traces of its technology could survive and end up in space, either via the deterioration of megastructures and other smaller spacecraft or via powerful asteroid strikes on once-inhabited exoplanets. Once in space, tiny specks of metal or other artificial materials could be ejected from star systems by powerful gusts of stellar wind and eventually drift toward us.

Using computer models, the team predicted that pieces of tech up to 3 micrometers across (three-millionths of a meter, or about 3% the width of a human hair) could escape their star systems and travel across interstellar space for up to 1 billion years. Then, they estimated how much of this material could be reaching the solar system and how likely it would be to end up on the moon. (We already know that interstellar dust can penetrate the inner solar system because scientists found some within samples collected from the surface of Bennu, an asteroid that orbits between Earth and Mars and was visited by NASA's OSIRIS-REx probe in 2020.)

To date, no lunar samples have contained any technosignatures. However, the scientists who studied them were likely not looking for such particulates, and the samples were probably too small to yield meaningful results, the study authors argue.

The researchers believe that a sample of lunar regolith with a volume of 35 cubic feet (1 cubic meter) could be enough to find at least one technological fragment. The team also proposed ways of combing through the material using microscopy, industrial materials analysis and AI-assisted imaging.

However, if such a sample does not yield any results, this would not necessarily disprove the researchers' hypothesis and may instead mean their models are off and a greater sample size would be required, the team wrote.

"Eminently reasonable"

Several upcoming space missions will collect fresh samples from the lunar surface, including China's recently delayed Chang'e-7 mission and future missions in NASA's Artemis program. These samples could potentially hold technosignatures, although the volume of regolith collected will be far less than what the researchers are proposing.

Therefore, we may have to wait until humans establish a permanent moon base before astronauts can collect enough material to be analyzed properly. This may not be that far off, as both the U.S. and China are planning to construct lunar bases within the next decade. Researchers also think the samples could be analyzed on the moon rather than on Earth.

As a result, the SETI Institute, which leads the international hunt for technosignatures, views the new idea as very promising.

"The concept of searching the lunar regolith for microscopic technosignatures is at once extraordinarily original and eminently reasonable," Bill Diamond, president and CEO of the SETI Institute, who was not involved in the new study, said in the statement. "This is a novel addition to the search methodologies applied to seeking evidence of technology as a proxy for life and intelligence beyond our solar system and we are excited at the prospect of bringing this to fruition."

Extraterrestrials quiz: Are you an alien expert, or has your brain been abducted?

The CL Companion is Swarovski's dedicated compact binocular, originally introduced 15 years ago, but has now been redesigned in 2026 to appeal to a wider, younger audience. RSPB research found an increase of around 1,000% in birdwatching among Gen Z in the UK since 2018, with a similar boom now happening in the US.

The CL Companion sits between the pocket-size CL Pocket and full-size EL and NL ranges, making it the perfect mid-range model that combines portability with excellent optical prowess.

The Companion is a grab-and-go, "take it anywhere and everywhere" binocular that is perfect for many different activities, whether that's spotting birds, scoping out your hiking trail or sweeping across the starry sky at night.

We spent a week with both the 8x30 and 10x30 CL Companions to test them out, with the former being ideal for tracking movement with a wider field of view, while the latter brings you closer to the details.

Swarovski CL Companion: Design

• Simple, fuss-free design
• Rubber grip ensures a secure hold
• Choice of three earth-tone colors

The biggest change in comparison to the old-style CL Companion is in the design. The original version was more of a traditional binocular aesthetic, but this updated design breathes life into the range with three new earth-toned colorways: mountain green, desert orange and safari brown. While some users have said they look somewhat toyish (or just downright ugly), when you handle them in person, they are much more sleek and stylish than the product images would have you believe.

Both the 8x30 and 10x30 weigh just 1.21 pounds (550 grams), so you can easily wear them around your neck all day without even knowing they're there. They're compact enough to put in a large jacket pocket, or you can just wear the included carry bag.

The central focus wheel has just the right amount of slip to make it easy to change focus, but is not so loose that you don't have enough control over it. The diopter is located on the front of the focus wheel, which felt a little off at first, but once we set it, there was no danger of accidentally changing it.

They also have generous eye relief, which is great news for users who wear glasses. The eye relief is 19mm on the 8x30 and 18mm on the 10x30. We used them on a bright, sunny day during a heatwave and were easily able to observe while wearing sunglasses with no issues at all.

Swarovski CL Companion: Performance

• Sharp optics throughout the image circle
• Minimal defects
• Excellent for daytime birding

Out in the field, the CL Companions proved to be particularly well suited to daytime birding — although with 90% light transmission, they'll still hold their own at dawn or dusk. Both the 8x30 and 10x30 had a clear, sharp image, with plenty of detail across the image circle. The 8x30 felt particularly easy to use when trying to pick up birds quickly, while the 10x30's extra magnification was great for getting a closer look at more distant subjects.

The color reproduction was natural, and the views had good contrast without looking over-processed. Fine details on feathers were easy to pick out, even on smaller birds. There was a tiny sliver of color fringing towards the edges in high-contrast situations, but it didn't spoil the view whatsoever, and you'd only notice it if you were actively looking for it (which we were). Every time we have used a pair of Swarovski binoculars, there's a three-dimensional viewing experience and depth to the image that you just don't get with cheaper brands.

Both models performed well in the bright daylight conditions we were using them in, both in terms of optical clarity and comfort when using them for longer periods. Their small size and light weight meant we could comfortably track birds in flight without having to take breaks, which is often a dealbreaker when it comes to choosing a pair of birding binoculars.

Swarovski CL Companion: Functionality

• Wide field of view for birding
• Waterproof down to 13 ft/4 m
• 3m close focusing distance

The wide field of view is one of the more useful features for birding. The 8x30 has a 549 ft (140m) FOV, while the 10x30 has 377 ft (115m) — both of which are wider than the original generation of CL Companion. Both made it easy to find birds when scanning trees and bushes, and there was enough space around the subject to follow them easily after they took flight.

The close focusing distance of 9.8 feet (3m) was also handy when birds came closer, and enables you to observe insects like bees and butterflies without spooking them by getting too close. And with the smooth focus wheel, it was easy to change focus between the two distances.

Both models are waterproof down to 13 feet (4 m), which is likely more protection than most people will need, but it is reassuring when using them outdoors in the rain, or if you were to accidentally drop them in a puddle.

Should you buy the Swarovski CL Companion?

On paper, they tick all the boxes. The optics are excellent, and they're lightweight and easy to carry. But with Swarovski being very upfront about the fact that it’s going after a younger audience with these CL Companions, we have to wonder what young person would have a spare $1,500 to spend on a pair of binoculars? It's not a small investment, so you'd need to be a dedicated observer to spend that kind of money.

That said, they're much more than your typical compact binoculars. They're a genuinely impressive binocular with stunning optics built into a small and compact package. Typically you need to compromise on one or the other, but the CL Companion gives you the best of both worlds.

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The brain undergoes dramatic changes during puberty and pregnancy, but during menopause, the organ's structure remains remarkably stable, a new study suggests.

The research, published Sept. 8 in the journal Nature Communications, examined the brain's gray matter, which mostly includes the wrinkled outer surface of the organ, called the cerebral cortex. Past studies have found that the volume of gray matter shrinks markedly during puberty and pregnancy, likely reflecting a fine-tuning of neural circuits during those periods.

There's also a gradual decline in gray matter during adulthood that's seen as a normal part of aging, said study co-author Sophie van't Hof, a doctoral student in psychiatry at Amsterdam University Medical Center. However, during the transition leading up to menopause, that gradual loss of gray matter levels off temporarily, the study found.

"This study provides the first direct longitudinal comparison of brain structural changes across all three major female hormonal transitions," said Magdalena Martínez-García, scientific director of maternal health for the Ann S. Bowers Women's Brain Health Initiative, a brain imaging consortium headquartered at the University of California, Santa Barbara.

"I really appreciate the effort that went into finding and curating such an impressive longitudinal dataset of the female brain," Martínez-García, who was not involved in the study, told Live Science in an email.

Declines in puberty and pregnancy

For their analysis, the researchers gathered data from the UK Biobank, a biomedical database that contains information from 500,000 U.K.-based adults. That data includes MRI scans of people's brains, which the team used to study brain changes in menopause.

To look at puberty and pregnancy, the researchers pulled from several brain-scan datasets that had been compiled by Leiden University in the Netherlands.

In all, the study included data from 1,095 brains across the three life stages. They analyzed each participant's brain at two different time points, examining how each person's brain changed over time and how it compared to others' brains.

The youngest cohort included participants who hadn't started menstruating yet, as well as those who'd recently started and those who'd already had periods for an average of 19 months. The pregnancy cohort included 40 who'd had their first pregnancy during the study and 30 who'd had second pregnancies, as well as 40 women who'd never been pregnant, as a point of comparison.

As in previous studies, the researchers observed that both the girls entering puberty and the pregnant women lost gray matter. But scientists don't necessarily see these declines in gray matter at puberty and pregnancy as negative.

It’s a hypothesis, but "we actually see it as something positive," van't Hof said. "We see it as neural fine-tuning."

During puberty, that gray-matter loss is thought to be a normal part of the brain's development into adulthood. Its function in pregnancy is not well understood, van't Hof noted, but the evidence to date doesn't suggest that it contributes to "mommy brain" — the brain fog and forgetfulness some women can experience postpartum.

"I'm not saying that there's no neurobiological basis for this mommy brain, but up until now, we haven't found it," van't Hof said. "But what's really important is that gray matter decline is not equal to cognitive complaints."

Stability in menopause

The analysis included 120 women who entered menopause during the study. At the first time point, these women had not gone a full year without a period, but by the second time point about 3.5 years later, they had. Menopause is defined as the point at which a full year has elapsed since a person's final period.

The researchers compared these women to two other groups: about 50 women (average age 51) who had not had their last period yet and over 670 women (average age 55.5) who had already had their last period.

During late perimenopause — the final stages of the transition to menopause — the brain's gradual decline in gray matter paused, van't Hof said. Then, in postmenopausal women, that gradual decline of gray matter resumed. The exact timing of that pause differed for each woman, but it occurred consistently across the group, van't Hof noted.

The most striking finding was the lessening of the "ongoing age-related decline in brain volume during the transition into and out of menopause, compared with the more stable premenopausal and postmenopausal groups," Martínez-García said. This is an "interesting finding that adds to our understanding of how dynamic the female brain can be across the lifespan."

Factors such as whether participants had taken hormone replacement therapy for menopause and the number of children they had given birth to did not have a measurable impact on the results, the study authors noted.

In general, complaints of brain fog are widespread just before, during and after menopause, van't Hof said. This could be attributed to declining hormone levels and sleep disruptions.

"We have no clue if there's a neurological basis [for that brain fog], because, again, this is the first study to look at it," she said, adding that more studies are still needed to learn more.

"As with any study, there are some limitations to consider, but overall, I think the methods and conclusions are well supported by the data available," Martínez-García said. Both Martiniz-Garcia and van’t Hof said that they hope other researchers build on these findings to deepen scientists’ understanding of female neurobiology at every stage of life.

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

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The largest hoard of Viking Age silver ever found in Finland — which contains almost 10 pounds (4.5 kilograms) of coins and jewelry — has been unearthed by a metal detectorist about 95 miles (150 kilometers) north of Helsinki.

The hoard had been divided into two deposits and buried in birch-bark containers. Although the coins and jewelry likely date to between A.D. 1000 and 1050, it's unknown exactly when they were buried, Esko Tikkala, an archaeologist at the Lahti Historical Museum who excavated the hoard, told Live Science in an email.

The hoard has not yet been fully cleaned, separated and counted yet, but there are thousands of pieces, Tikkala said. "There are quite a lot of coins in this hoard," he said. "I have not had time to go through them."

Metal detectorist Kalle Lappinen found the two deposits Sept. 3 and immediately contacted the museum. Archaeologists inspected and properly excavated the finds the next day, according to a translated statement.

Tikkala described the hoard site as beside a rock outcrop in a forest near the town of Sysmä. Several other buried hoards had been found in the same region of Finland over the past 10 years, Tikkala said.

Although it's challenging to determine why specific hoards were buried, a recent study of more than 15,000 Roman-era (the eighth century B.C. to the fifth century A.D.) hoards found that they were hidden for multiple reasons, including for tax evasion, votive offerings, and safe storage in times of uncertainty.

Tikkala said the two deposits of the silver hoard were buried between two stones about 18 inches (45 centimeters) below ground and about 39 feet (12 meters) apart. There were no signs of any burials nearby, but the surrounding area had not been properly studied, he said.

Tikkala added that the coins came from areas that corresponded to present-day Germany, Sweden and Great Britain. There were also some dirhams —‬ silver coins made in the Islamic world. Dirhams previously found in Finland generally date to between about 800 and 1050, he said.

The hoard also contains several pieces of jewelry, including a silver bracelet, and "payment silver" in the form of hack silver (also called hacksilber) — pieces of silver that could be cut into smaller pieces for payments according to their weight.

The weight of the precious metal alone would make the hoard worth almost $10,000 today.

From the Viking Age, but not from Vikings

Although the hoard is from the Viking Age (traditionally, from the 793 attack on Lindisfarne until the 1066 defeat of a Viking army at Stamford Bridge in England), that doesn't mean it was buried by Vikings, Tikkala said.

"The term Viking Age does not imply that there were Vikings in Finland," he said. "We have no sources suggesting that Finland was 'Viking' in the same sense as regions of present-day Sweden, Norway, and Denmark."

Instead, Finnish historians and archaeologists had adopted the term to designate the period, he said. But the area now known as Finland was not culturally or politically part of Viking Scandinavia.

The next stage of the archaeological investigation will be to properly study the site where the two deposits were found, as well as their surroundings, Tikkala said; after that, specialists in Viking Age coins will try to identify the coins and prepare a detailed report.

"There will definitely be scientific articles published on the hoard as a whole, as well as more detailed studies of the coins themselves," he said.

Until now, Finland's largest Viking Age hoard was found in 1895. Buried at Nousiainen, about 130 miles (210 km) southwest of Sysmä, it contained more than 1,700 silver coins but weighed only about half as much as the newfound hoard.

Other Nordic countries have also recently reported their largest Viking Age hoards. A cache of more than 4,700 coins was found in Norway this past spring, and a homeowner in Denmark unexpectedly discovered a hoard of more than 700 silver objects weighing more than 40 pounds (18.5 kg) in their backyard, also in the spring.

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Many people are familiar with melatonin, a hormone that helps ready the body for sleep. But there's another, lesser-known chemical in the brain, called orexin, that tips the scale in the other direction: waking the body up.

In 1999, two scientists independently uncovered the function of orexin and published papers about it. Dr. Masashi Yanagisawa, a molecular biologist and physician now at the University of Tsukuba in Japan, came across orexin while studying the interaction of receptors and chemicals in the brain. Dr. Emmanuel Mignot, now the director of the Stanford Center for Narcolepsy, homed in on orexin while studying narcoleptic dogs. (His Chihuahua, named Watson, has narcolepsy, and he previously had another dog with the condition, named Bear.)

This year, the pair of researchers won the coveted Albert Lasker Basic Medical Research Award for this fundamental finding that helped reshape our understanding of sleep. Their work has since led to the development of drugs for insomnia and narcolepsy.

Yanagisawa told Live Science that, at the start of his research career, he didn't expect to end up studying sleep. Mignot, on the other hand, had an early interest in understanding narcolepsy so that better treatments for the neurological disorder could be developed. Live Science spoke with Mignot about the discovery of orexin and how the field might progress in the future.

Nicoletta Lanese: What initially drew you to studying narcolepsy?

Dr. Emmanuel Mignot: There were three things that attracted me to narcolepsy: Number one, it was a human problem. It was already known [at the time] that it was not super rare. I'm not saying it's super common, but 1 person per 3,000, 0.03% ‪—‬ it's reasonably common. And nobody cared about it. I would talk to neurologists and they'd say, "Oh, I've never seen one case in my entire life." So I would say, "Yes, of course; you miss them all." That was the state of the play at the time.

Number two, was what this was a quintessential sleep disorder [in which sleep itself is disrupted]. I thought that if we found the cause of this disease, we could potentially discover something totally new about sleep — a fantastic entry point to a mystery.

The third thing that made me ready to go there was that it was tractable. A lot of problems are not tractable.

NL: Why did you start working with the dogs with narcolepsy?

EM: I studied the pharmacological basis because I was trained in pharmacology, and as a psychiatrist, and I discovered how this drug modafinil [a stimulant-based narcolepsy treatment] was working. But quickly, I realized I'm not going to find the cause by doing pharmacology. I'm only going to explore what's known.

That's when I started to fall in love with genetics, even though I was not trained as a geneticist. I said, "We have to find this gene in the dogs." It looks like they have all the symptoms. It was a huge bet, and it took me 10 years because I was definitely … overoptimistic. But it was worth the price at the end.

NL: And scientists already knew about narcolepsy in dogs at that time?

EM: The guy at Stanford that started the sleep program was called Dr. [William] Dement. He was a graduate student in Chicago in the 1950s, when [Eugene] Aserinsky and [Nathaniel] Kleitman discovered REM sleep. He had the foresight to understand that this was an important discovery.

[Later], he discovered that narcolepsy was really a disorder where people go into REM sleep and have this very abnormal dreaming. He came in 1970 to Stanford, and the first thing he did after his medical school was to start a clinic to see patients with narcolepsy. Around then, he spoke at an American Medical Association conference in San Francisco, and he discussed different sleep disorders, including narcolepsy. And then there was someone in the audience that said, "Oh my god; I have a dog with your disease. Every time it gets excited — boom — it collapses. And it sleeps all the time."

That dog had already been euthanized, but it still gave him the idea that these dogs have narcolepsy — maybe we should try to get some. So he went to a lot of veterinarians to talk to them about it, and they identified a whole series of dogs, including the first poodle, Monique, who had narcolepsy. And they started this little colony of dogs. Initially, they tried to breed them, but most cases of narcolepsy are actually not genetic. Then, in 1977, they got a whole litter of Dobermans, and then Labradors, that had some form that was genetic.

So when I arrived, it was in 1987. They already had the dog colony. I came to study the pharmacology, to try to find a better treatment for narcolepsy. But I did stand on the shoulders of giants.

NL: At that time, it's not like you had a complete dog genome. Did that make studying their genetics challenging?

EM: It was crazy. A couple of human genes had been isolated, and mouse genes, but it was a handful. We didn't even have the full genome map in humans. And meanwhile, dogs — no pun intended — were in no man's land. Very little was known.

It took me 10 years. I had times where some people didn't believe that the dogs had narcolepsy. There were a few depressing moments, but I was convinced that was the right thing to do.

NL: When you ultimately found the receptor for orexin, did it surprise you? It strikes me as surprising that there would be a discrete "switch" in the brain that controls wakefulness.

EM: I was lucky. Honestly, I had no idea. I got enamored with genetics because what I love [about it] is you can find something without any hypothesis. You just search for it, and what you find tells you what it is. You have no prerequisite for knowing what you would find.

I could have found something much less significant. That was a dream, to find a GPCR [G-protein coupled receptor, a protein on the outside of cells]. Can you imagine? A drug target.

Then, it turned out to be immediately applicable to humans. That, too, was a lot of luck; let's be honest. I was just trying to find the cause of one thing and one step at a time; it could have been something very complicated. It turned out to be simple.

Was I surprised? No, because I was not expecting one or another.

NL: Do you recall what the reception was like when the initial finding was published?

EM: It had an immediate effect, for several reasons. For example, I was seeing a lot of patients with narcolepsy at the time, but they were all old folks that had had narcolepsy forever. A lot of people would tell me, "I think I had it from when I was born, because I don't remember." We were never seeing children.

But after narcolepsy was described — the dog gene — suddenly narcolepsy became much more famous. And what happened is that people started to pay attention to narcolepsy, and we started to see kids. In kids, the picture is so much different. They gain an enormous amount of weight; it's very abrupt. It's a little bit different than what you see in adults, where they have adapted to it.

That was, I think, a practical consequence of the discovery. It really put narcolepsy on the map.

The second thing that happened is, all the drug companies started to develop hypnotics [sleeping pills], trying to block the orexin. They developed hypnotics relatively quickly, and they are very effective. They are probably safer than benzos [benzodiazepines] and so forth.

NL: Is it considered safer because the orexin blockers better replicate natural sleep?

EM: We know that the orexin definitely drops during sleep, so blocking it is definitely a way to recapitulate that drop; that's true. It's an awake-promoting system, so if you remove something that makes you more awake, it's safer than inducing sleep by shutting down the brain.

NL: As you moved to studying narcolepsy in humans, you found evidence that there might be an autoimmune response involved; it's been suggested that such a response may be harming the cells that make orexin in the brain. Was there suspicion that the condition had an autoimmune element previously?

EM: It's not something I 100% discovered. In 1983, before I came to study narcolepsy, there was a guy in Japan who I met, called Yutaka Honda. [Editor's note: Honda's research linked narcolepsy to the human leukocyte antigen (HLA) region of the genome, which helps regulate immune responses.]

The HLA is the way the immune system sees the world. That had just been discovered as very important for transplantation, because it's very polymorphic [takes on different forms] from one person to the next. They [Honda's group] found that all narcoleptics had a particular genetic variant, called HLA-DR2. This was a total surprise.

When I came, that was already known. But then people really looked and tried to see if the disease was autoimmune, but they couldn't find anything — no autoantibody, nothing. It was all negative.

I did a study with African Americans, and in African Americans, I found that this DR2 marker was not the best marker for narcolepsy. It was a gene just next to it that was called DQB1*06:02. [Editor's note: That HLA variant is now recognized as a strong risk factor for narcolepsy, particularly for narcolepsy type 1 (which involves a symptom called cataplexy).]

I'm very proud of that study because I think it's the first time that people used human diversity to actually map down a genetic factor more precisely, which now is used commonly. It's called transethnic mapping.

NL: New treatments that target orexin have just been approved. Do you see those therapies as an extension of your earlier findings?

EM: Of course. I was trained as a pharmacologist originally, so obviously, I do a lot of clinical trials. I see my patients totally transformed by this medication. It's just amazing. I'm so fortunate. How could you get a better reward than seeing your patients totally transformed by this medication?

It's going to have a lot of other applications [beyond narcolepsy]. Some people think it's going to be very helpful for ADHD; some people think it could be very helpful for depressed people with excessive sleepiness. We don't know, really; there's a lot of possibilities.

Another thing I'm excited about is that I have a few patients with [both] narcolepsy and schizophrenia. You cannot give them stimulants. If you give them modafinil or another dopamine stimulant [for narcolepsy], they have even more hallucinations. Often, they are sedated by their medication, and we are very poor at making people more motivated and active. These [orexin-activating] drugs seem to have effects beyond just waking people up. They seem to increase motivation.

You don't know until you try, but I'm sure it's going to have other applications.

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

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To the untrained eye, Xiaoyu Shan's lab bench looked like a home gardening experiment gone bad: dishes filled with dirt — some that looked like mud pies and others that were bone-dry — and not a plant to be seen.

But those dishes held a warning. The dirt that Shan, a postdoctoral research associate in biology and biological engineering at Caltech, was studying contained soil microbes. And those soil microbes were exhibiting a concerning propensity: In dried-out soil, they were evolving to become more antibiotic resistant.

The study describing those findings, published in March, systematically showed that drought conditions could fuel the evolution of antibiotic-resistant bacteria. Most of this resistance is driven by humans' misuse of antibiotics, which spurs bacteria to evolve genes that help them ward off the drugs. But the Caltech study raised a new worry: As many places face increased drought conditions, climate change itself could act as a selective pressure that could supercharge the evolution of these drug-resistant superbugs.

"We can expect to have more resistant bacteria being selected for in certain places around the globe," said Dianne Newman, a Caltech microbiologist and co-author of the study.

Increased antibiotic resistance is just one way that climate change is likely to put new populations at risk of multiple types of infections.

And this increased disease burden will coincide with climate change scrambling supply chains, eroding nutrition and stressing our health in other ways.

"No individual metric really does justice to the overall risk and health and well-being of these multiple stressors being exacerbated all at once and compounding each other," said Marina Romanello, a principal research fellow at the Institute of Global Health at University College London.

Warm-weather disease

In the small mountain town of Bailey, Colorado, which lies at an elevation of 7,740 feet (2,360 meters), May often brings snowstorms that can blanket the ground in white even as the sun starts to bake the plains at lower elevations. But on Memorial Day 2026, the forest floor was dry and ticks quested their way along blades of grass, seeking a blood meal.

A mild winter in most of the country means ticks — and the diseases they carry — are a rising concern. In April, the Centers for Disease Control and Prevention (CDC) reported that emergency department visits for tick bites were at their highest for that month since 2017. That trend isn't a one-off, according to the CDC; as temperatures rise, insects and arthropods can survive longer in the year and farther north.

As a result, vector-borne illnesses such as Lyme disease (spread by black-legged ticks in the Ixodes genus) and West Nile virus (spread by mosquitoes) will become more common in increasingly northerly locations. Already, alpha-gal syndrome, which is not an infection but is transmitted by the Lone Star tick (Amblyomma americanum) and causes an incurable allergy to red meat, is also seeing a dramatic rise as the species expands its range across the Northeast. Positive tests for antibodies to the alpha-gal molecule have increased by 100 times between 2013 and 2024.

Right now, almost half a million people are treated for Lyme disease each year, and the CDC records more than 8,000 cases of other tick-borne diseases annually across the country. It's not clear how this will change as the climate warms. One 2022 study found major increases in Lyme disease only at levels of warming of 6.3 to 9.9 degrees Fahrenheit (3.5 to 5.5 degrees Celsius) by 2100, but that much warming that fast is now considered an implausible scenario. However, the researchers saw a huge amount of uncertainty in the numbers, given the number of variables that affect whether a spreading tick population will transmit more disease, such as how often people go outside or what steps they take to avoid tick bites. Tick-borne illnesses are likely also underreported, so even the true number of illnesses transmitted each year right now is unknown.

But ticks are responsible for spreading 90% of all vector-borne diseases in the U.S., so any trends in the suite of illnesses spread by ticks are likely to affect thousands to tens of thousands of people.

An even more ubiquitous bloodsucker, the mosquito, currently spreads only a few diseases in the U.S. The most common and most serious is West Nile virus, which mosquitoes catch from feeding on infected birds. As of Sept. 8, 504 cases of West Nile virus had been reported in the U.S. in 2026, with 363 of them affecting the central nervous system. And because fewer than 1% of West Nile cases progress to the central nervous system, those numbers likely represent a dramatic underreporting of milder cases, which can cause months of fatigue in some people, in addition to acute flu-like symptoms, such as fever, headache and body aches.

Mosquito-borne illnesses like West Nile are expected to spread more quickly in warming temperatures. Heat helps mosquitoes stick around longer during the year, much like it does for ticks. It also speeds up the transmission and replication of the virus inside the mosquito, since the insects are cold-blooded and thus their metabolism is ruled by the weather.

"Except for places that are already really, really warm, we should expect that the replication rate of the virus inside the mosquito will speed up," said John Drake, director of the Center for the Ecology of Infectious Diseases at the University of Georgia. "That shortens the generation time, and that means we expect there to be more transmission."

Even though mosquitos love water, climate-related drought could ironically nearly triple the number of human West Nile cases in the U.S. over the next 30 years from around 2,000 reported cases (according to CDC data) to between 5,000 and 6,000. That's likely because in drier conditions, more mosquitoes are infected, possibly because birds, the intermediate host of the virus, either congregate more closely with mosquitoes around water sources or breed less readily in drought, meaning the fraction of birds that carry the virus is higher than in more water-abundant times.

Mosquito-borne diseases long ago eradicated from the U.S. could also resurge with warming temperatures. The southeastern United States will become more prone to malaria and dengue fever transmission under all levels of warming; summer 2026 saw more than 40 locally-acquired cases of dengue fever in Florida. Public health surveillance and disease-control measures have largely stopped those transmission chains, but the likelihood is that society will have to pour more money into beating these diseases back again in future decades. For example, there are malaria vaccines approved for children, but currently, they are recommended only in areas where the illnesses are endemic. If malaria were commonly found in the southern U.S., millions of Americans might need vaccines, including susceptible adults.

"If we were to get endemic diseases like those in the U.S. again, it could become a huge burden and it could be quite costly," Drake said.

Disaster and disease

Flooding is another factor that's exacerbating vector-borne disease under climate change. As climate change worsens, extreme weather events will, too. Because warm air can hold more moisture, many areas will see increased episodes of heavy rainfall and hurricanes will become more intense.

"Flooding creates habitat for these mosquitoes," Drake said.

Disasters also spur the spread of other diseases that are usually quite rare in the U.S., such as leptospirosis, a bacterial infection that spreads from animals to humans via animal urine. Floodwaters may be contaminated by the bodies of drowned animals; in 2022, after Hurricane Fiora hit Puerto Rico, leptospirosis cases leapt by a factor of 3.6 to over 10 cases a week.

After Hurricanes Matthew and Florence in 2016 and 2018, respectively, North Carolina saw an 11% increase in emergency department visits for gastrointestinal illnesses. Black and American Indian residents were the most affected, likely because discrimination over generations has disproportionately pushed Black Americans and Native Americans to less desirable, more flood-prone land, the researchers found.

Cycles of precipitation, drought and subsequent dust storms can spur the spread of Valley fever, a fungal respiratory disease that causes an estimated 700 to 1,100 deaths per year, mostly in the U.S. Southwest. Valley fever is already on the rise, with cases in Arizona, one of the hotspots for the disease, doubling from about 64 cases per 100,000 people in 2005 to 145 cases per 100,000 people in 2022. As the West warms and dries, Valley fever is likely to spread from its stronghold in the Southwest and become endemic in Idaho, Wyoming, Montana, Nebraska, South Dakota and North Dakota, putting millions more people at risk.

The infectious disease risk from natural disasters tends to stack on top of other health problems stemming from these catastrophes. Flooded buildings can harbor mold that can worsen allergies, asthma and other respiratory illnesses. When major storms cause power loss, people turn to generators for electricity, which release pollutants linked to asthma. Though it's often hard to track the effects of these disasters, one study found that flooded regions after Tropical Storm Imelda in Texas in 2019 saw 10% more emergency department visits for asthma than nonflooded regions did.

Moreover, the threat to life and livelihood from these disasters can cause mental health conditions, such as post-traumatic stress disorder, Romanello said. The problems compound on each other, she said; already, she has heard reports from Africa about malaria outbreaks, fed by warming, and health workers struggling to reach the affected regions because flooding, also exacerbated by warming, has washed out roads.

"What is the most concerning aspect is that all of that is happening together, so we're seeing all of this risk being exacerbated at once," she said.

Antibiotic resistance on the rise

As Newman and Shan's work shows, as spots around the U.S. face new infection risks, existing treatments may become less effective. Their work showed that drought concentrated the natural antibiotics that bacteria make in the soil, making it harder for bacteria susceptible to the compounds to survive. As a result, the microbes with genes for antibiotic resistance did better. The problem for human health is that bacteria are very good at gene swapping, so these soil microbes can easily pass their antibiotic resistance superpowers to bacteria that infect people, their research showed.

"Gardening, breathing dust ‪—‬ that's how it happens," Newman said of human and soil bacteria coming into contact. "We are constantly encountering bacteria in our environment."

The researchers found an association between drought and antibiotic resistance reported by hospitals.

They aren't the only ones. A recent study on Salmonella, a bacterium that causes about 1.35 million cases of food poisoning each year in the U.S. alone, found that temperature and rainfall promote antibiotic resistance in this microbe. "Globally, climate change was linked to about a 10% increase in Salmonella resistance gene abundance," said study first author Zhen-Chao Zhou, an ecology researcher at the Chinese Academy of Sciences in Beijing. Other microbes show similar effects.

Meanwhile, warmer conditions help bacteria grow faster, adapt to stress and swap resistance genes, Zhou said, while drought concentrates them in limited water sources where they mingle freely. Climate-change-induced flooding can then, in theory, spread the resistant genes far and wide.

Combating the compounding risks requires both public health and climate mitigation approaches, experts say. Not only does the world need to cut greenhouse gas emissions, but people also need to use antibiotics more carefully, Zhou said; improve sanitation practices, such as sewage management, around the world so that antibiotic-resistant strains don't spread as easily; strengthen food safety; and expand disease surveillance. The public also needs to understand that climate change is a health issue, Romanello said.

"When we talk about tackling greenhouse gas emissions," she said, "what we're talking about is a sustainable livable future with healthy economies."

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A family photo album can reflect how physical traits, such as blue eyes or lanky limbs, have been passed down — but a new analysis suggests that the way personality emerges across generations is far more complicated.

The meta-analysis, published Sept. 2 in the journal Nature, is the largest of its kind ever attempted. The work identified over 1,200 genes linked to five personality traits: extraversion, agreeableness, conscientiousness, openness to experience and neuroticism.

However, the scientists behind the study said its most important conclusion is that no single gene determines whether an individual will have a particular personality trait. Instead, thousands of genes exert tiny effects that are likely impossible to disentangle from environmental factors that shape our behavior.

Twins and DNA sequencers

Researchers have studied the link between genes and behavior for decades. Before the ability to analyze the genome in detail, many early studies looked to identical twins.

Knowing that identical twins share nearly 100% of their genetic material, scientists compared their traits with those of nonidentical twins and other siblings. Some studies compared twins raised in the same home with those raised in different homes in an attempt to separate the influence of upbringing from genetics. These efforts concluded that personality was roughly 50% heritable. ("Heritability" measures how much of the variance seen in a given trait can be explained by genes.)

The advent of gene sequencing enabled geneticists to calculate the influence of genes with greater precision than twin studies did. The most powerful tool in this arsenal is the genome-wide association study (GWAS), which can link traits to gene variants in detail. These statistical analyses require sample sizes in the millions, though.

The new study was a large collaborative project called the Revived Genomics of Personality Consortium, which brought together 46 cohorts of participants who'd had their genomes sequenced. Each person had been asked something related to one of the Big Five personality traits. The team had data from roughly 600,000 people about the first four traits — extraversion, agreeableness, conscientiousness, openness to experiences — and data from over 1.1 million people about their levels of neuroticism.

Generally, as geneticists have leveraged larger and more powerful GWAS, many traits have shown increased heritability because these bigger studies can identify more subtle genetic links, said Brent Roberts, a psychologist at the University of Illinois at Urbana-Champaign who was not involved in the new study. But "with personality, it was really clear from the get-go that it was different," Roberts said.

Earlier GWAS had suggested that the heritability of personality from common gene variants was roughly 5% to 15%, far lower than the estimate suggested by twin studies. The new work has confirmed those low numbers, said study co-author Michel Nivard, a genetic epidemiologist at the University of Bristol in the U.K.

It may be that GWAS do not capture extremely rare variants that might link personality traits in certain families, which means the heritability may be slightly underestimated, Nivard suggested. Additionally, twins are more likely to rate their personalities as similar for reasons unrelated to genetics, so the twin studies may have overestimated the heritability of personality, Nivard noted.

Cutting out confounders

It can be difficult to control for confounding factors in GWAS. For example, if scientists were investigating the influence of genes on academic achievement, genetics only tells part of the story; a person's socioeconomic status and access to books and tutoring also influence their education.

But in this case, Nivard and his colleagues did not find confounders in measuring personality. The researchers found that the genetic effects on personality are the same within families as they are among unrelated individuals.

"We've basically been able to rule out that there's any straightforward, simple social processes by which your parents directly influence your personality," Nivard said.

A key takeaway from the study should be not to focus too much on the different contributions of genes versus environmental factors in a trait as complex as personality, Roberts said. Our moods and minds are a collaboration between the two factors, not a tug-of-war, he argued.

A study to properly measure this interplay would be vastly expensive and would require following participants for decades. "This is where the limitation of human genetics research is really profound," Roberts said. Part of the problem, he added, is that while our DNA sequence is fixed, how the body accesses and reads DNA varies significantly depending on the environment a person finds themselves in. In other words, which genes get turned on and when are variable factors.

Assessing this enmeshed relationship using only the DNA code we are born with is like trying to predict every move of a couple's dance by looking at how they hold each other before the music starts up.

Nivard and his team can now use this powerful data source to learn more about personalities within groups of people, he said. Nivard predicted that, even once geneticists have mapped all the rare gene variants that may influence personality, some genetic influence will still go unaccounted for; processes such as the interaction between the environment and gene expression are still not fully understood. He called these the "unknown unknowns." Identifying these factors is the next frontier for the genetics of personality.

"It's where we're headed," Nivard said.

Mercury, which is about one-third the size of Earth, may have shrunk more in its evolution than scientists originally thought.

A new study suggests that the tiny planet may have contracted 10% to 30% more than previous models suggested — meaning the planet’s total diameter shrunk almost 12 miles (19 km) since Mercury was formed. (Mercury’s diameter today is roughly 3,032 miles (4,880 km).

Previous missions overlooked the extent of the shrinkage because impact-crater debris on Mercury's surface hid the evidence, according to a study published Thursday (Sept. 10) in the journal Geophysical Research Letters. That size difference is important when researchers consider the planet's history, said Gaku Nishiyama, a planetary scientist at the German Aerospace Center Institute of Space Research and an author of the study.

"Because Mercury's evolution is driven by its cooling, the amount of contraction — an indicator of the extent of cooling — is one of the most important observables that can be compared to models for estimating its evolution scenario," Nishiyama told Live Science in an email.

There could also be implications for the planet's composition. For example, more shrinkage at Mercury could mean the planet would have a larger metal core and fewer light elements, such as silicon, inside that core, according to an American Geophysical Union statement.

"The interior of Mercury would reflect its formation," Nishiyama said, and possibly hint at the innermost part of our solar system. "Therefore, to understand how our solar system has evolved up to now, information that can be extracted from this estimation — such as core composition and initial temperature condition — is critical."

A violent history

Mercury and the rest of the solar system planets formed due to the gradual collisions and aggregations of rock and gas upon asteroids and comets. Some of those impacts that created the planets also released a lot of heat. Mercury has been slowly cooling from those ancient impacts, and its interior has been shrinking along the way.

While this kind of cooling affects the entire planet's landscape, impact craters can mask the effects because each crash into the surface generates its own surface changes, including debris and new divots. The craters build up over time, making it difficult to spot more ancient geology underneath.

Nishiyama's team compared two sets of maps from Mercury, using data from NASA's MESSENGER mission, which orbited Mercury between 2011 and 2015. One set of maps charted geological features showing contraction, and the other set estimated the roughness of the planet's surface. Their work covered the entire surface and demonstrated that the most rugged spots on the planet have fewer wrinkles from shrinking. In other words, according to Nishiyama, the debris from more recent impacts is covering up the evidence of shrinking.

Nishiyama said more information will help to confirm the estimate. Such data could come from the European Space Agency's BepiColombo spacecraft, which began its arrival sequence at Mercury earlier this month after nearly eight years of space travel. Once the mission settles in, the spacecraft will take higher-resolution imagery of the surface than MESSENGER did. Nishiyama's team expects BepiColombo to pick up smaller impact craters, as well as scarps and ridges, that could further refine the measurements.

"Stay tuned for future topography measurements by BepiColombo," Nishiyama said. "Future data from laser altimetry on BepiColombo will collect more information on planetary contraction by measuring topography more precisely."

IBM and NASA have partnered to create a new artificial intelligence (AI) model capable of processing decades of lunar data so scientists can more accurately map the moon's surface one day.

Decades of robotic lunar missions have left scientists with a massive, disjointed trove of data. Traditionally, this data has been parsed by limited transformer models such as SwinV2-B, created in 2022 as a general-purpose model to understand images and improve accuracy on photo recognition and related vision tasks. Spacecraft orbiting the moon captured this data using a mismatched array of sensors, without an accessible way to analyze or utilize it.

Specifically, images from high-resolution optical cameras, laser altimeters, radar reflectance tools and spectrometers that measure elemental density have created huge datasets — but unifying them into a cohesive picture of the lunar surface has been a labor-intensive and computationally demanding process.

To crack the data bottleneck, researchers from NASA and IBM teamed up to build the Lunar Foundation Model (LFM). This agile AI system is designed to piece together multimodal, multiresolution data to build a detailed picture of the lunar surface to support future missions. The team published their findings Sept. 10 in a technical paper shared with Live Science.

The scientists wanted to build a single, reusable backbone AI model that would be freely available to scientists via the open-source AI model repository Hugging Face. Because the model is open-source, researchers could fine-tune the AI to tackle specific questions as part of different projects.

For NASA, this includes thorny issues such as generating a reliable crater map so researchers can plot safe landing zones, or analyzing those craters for clues about the chemical makeup of the moon's interior and its history.

LFM also enables scientists to comb through the data for heavily shadowed sites on the moon that often conceal subsurface ice, which is critical for establishing long-term lunar bases. Volcanic activity can be tracked and collated too, which will allow future projects to avoid unstable terrain and reveal insight into the moon's thermal evolution.

Unique challenges

Processing lunar observations presents unique computational challenges that differ from those of similar models, which cover things like weather, geospatial data and heliophysics. NASA's Lunar Reconnaissance Orbiter and other spacecraft collect measurements across vastly different spatial scales, ranging from broad regional maps at a resolution of 100 meters per pixel down to terrain scans resolving at 1 m per pixel.

Because the moon lacks an atmosphere, extreme sunlight geometry is an issue, creating deep, deceptive shadows. Sunlight can also wash out subtle geological details, depending on when an image was captured.

To overcome these problems, the team compiled a layered benchmark dataset named SomBench, made up of nearly 2 million overlapping map patches called tiles. SomBench organizes that data into aligned tracks so data from completely different instruments, or imagery taken at different resolutions or angles, all end up together as long as they're capturing the same tiles.

The lower-resolution layers provide wide-angle overviews, as well as ultraviolet reflectance and elevation data. High-res layers combine tight, detailed camera shots with meter-scale terrain, slope and orientation maps. Specialized readings of thermal behavior, surface mineralogy and local gravitational anomalies also get layered in.

LFM learns to interpret all that layered data through a technique called masked-token learning, which is where parts of a dataset are hidden so the AI has to fill in the blanks. During training, the AI is shown a portion of a lunar tile, like its visible light appearance and elevation, and nothing else. The model then continuously predicts the concealed information across millions of examples, and learns the relationships between elements like lighting, terrain structure and physical geography.

Lighting analysis is built directly into the model's core architecture. Rather than forcing the model to infer light levels solely from shadows, researchers supplied explicit metadata describing solar angles and spacecraft positions. This allows the model to use its processing power to recognize actual terrain features rather than getting tricked by shadows.

One giant leap

The AI model performed well across four tasks it was evaluated on. In crater detection, it outperformed SwinV2-B by nearly 19% using half as many training labels. When estimating polar ice prospectivity within the top meter of regolith (lunar dust and rocks), LFM maintained strong predictive power with fewer data channels and reduced errors in identifying areas with high potential for lunar ice by up to 22% compared with SwinV2-B. Its performance on meter-scale crater mapping and rare volcanic landforms was similarly competitive with top custom models.

Scientists can customize LFM using lightweight techniques like low-rank adaptation — a way to fine-tune an AI by changing a tiny set of weights and not touching most of the original model. This allows researchers to tailor the model to specialized exploration tasks, without the steep computing costs of training an AI from scratch.

However, the researchers cautioned in a statement that the system best serves as a pattern-recognition assistant and is not a replacement for direct physical measurements. Nonetheless, the team said the model represents a major leap toward transforming decades of raw data into a unified, intelligent toolkit for future robotic and crewed lunar missions.

In the near term, scientists will likely use the LFM as a backbone for key lunar remote-sensing tasks, while the long process of fine-tuning it ramps up. Over time, the model will be refined for tasks like improved crater detection and mapping, segmenting subtle geomorphic units such as irregular mare (volcanic activity) patches, and improving polar ice detection by integrating terrain, illumination, and thermal layers.

The Canon RF 20mm f/1.4L VCM is an intriguing lens for photographers who want a wide field of view without sacrificing aperture. Its f/1.4 maximum aperture makes it particularly appealing for astrophotography, while the 20mm focal length offers plenty of room for landscapes, architecture and other wide-view scenes.

We took the lens out to the dark skies of Wales to photograph the night sky and the Perseids, giving it a real-world test in some of the best conditions we could find.

With a premium L-series build and a price tag to match, there's a lot to consider before adding this lens to your kit. We wanted to find out how it actually performs in the real world, and whether it's worth the investment.

Canon RF 20mm f/1.4L VCM: Design

• Premium, solid build
• Surprisingly manageable for an f/1.4 lens
• A few small quirks keep it from being flawless

The Canon RF 20mm f/1.4L VCM feels like a proper L-series lens from the moment you pick it up. It's solid and reassuringly well-built, but it never felt excessively heavy or awkward on the camera. At 1.41 pounds (519 grams), it's certainly not a tiny 20mm prime, but the weight is well balanced and it was comfortable to carry and shoot with. And considering it'll often be used for astrophotography, it'll be on a tripod a lot of the time anyway.

The focus and control rings both feel smooth and nicely weighted, while the switches and customizable buttons are easy to find without having to look at the lens. The weather-resistant build is another bonus for outdoor shooting, which will come in handy if you also use the lens for landscapes where you might encounter inclement weather.

The dedicated aperture ring is also a nice feature, especially if you prefer having more physical controls rather than relying on the camera body and remembering which dial is set to each setting. Plus, the clickable nature of the aperture ring is an ASMR dream.

Canon RF 20mm f/1.4L VCM: Performance

• Excellent low-light performance
• Sharp in the center with some corner softness
• f/1.4 makes a real difference under dark skies

A fast 20mm is a pretty exciting combination for astrophotography. It gives us plenty of sky to play with, while the f/1.4 aperture pulls in a lot of light. Under those dark skies, the Milky Way came through beautifully, with plenty of detail without needing to resort to boosting the ISO too high.

We took the lens out to Carmarthenshire in Wales under Bortle 3 skies to photograph the night sky during the peak of the Perseids, which also coincided with the new moon — the perfect recipe for astrophotography.

The center of the frame is where this lens is at its best. Stars are crisp and well-defined, which is exactly what we want from a lens that is being used for astrophotography. The edges aren't quite as impressive, though. There is some softness and a little stretching of the stars towards the outer parts of the frame, particularly when the lens is wide open. It's not enough to ruin an image, but it becomes obvious when zooming in and pixel-peeping at the corners.

Canon RF 20mm f/1.4L VCM: Functionality

• Quick and reliable autofocus performance
• Customizable controls are genuinely useful
• A practical choice for everyday shooting

The Canon RF 20mm f/1.4L VCM is very straightforward to use out in the field — especially in the dark. The autofocus was quick and reliable during testing, and for everyday shooting of landscapes, or even for video, this means there's very little to think about.

The customizable controls are useful, too. The lens function button and control ring can be assigned to different settings, allowing you to put the controls you use most within easy reach. It's a small thing, but being able to set the lens up around your personal shooting style makes it feel more intuitive and can save a surprising amount of time.

The 67mm filter thread is another practical advantage, as it's a common filter size, so you won't necessarily need to invest in an entirely new set of filters if you already own that size.

The lens doesn't feature a ton of bells and whistles, but that's not a bad thing. It's designed to be picked up and used without much fuss, and after spending time with it, we found that its simplicity is one of its strengths.

Should you buy the Canon RF 20mm f/1.4L VCM?

The Canon RF 20mm f/1.4L VCM lens makes the most sense for photographers who regularly work in low light or want a dedicated wide-angle prime. Astrophotographers are likely to get the most from it, but it also has plenty to offer for landscapes, architecture, interiors and environmental photography.

Its biggest appeal over a zoom is its f/1.4 aperture. If you already have a wide-angle zoom but regularly find yourself having to bump up your ISO in low light, this lens fills that gap while also offering the control of a fast prime.

However, it's a fairly specialist addition to a lens lineup, and the price makes it tricky to justify if you only occasionally shoot wide. If you need the flexibility of changing focal lengths, or if you primarily shoot distant subjects, you'd be served better by a zoom or longer lens

If this lens isn't for you

There may be no better month to get outside and look at the stars than September, when warm evenings meet rapidly lengthening nights, the Milky Way remains visible overhead, and the changing seasons can increase your chances of seeing the northern lights.

For stargazers in the Northern Hemisphere, summer presents an obvious problem: Darkness arrives late. By September, however, sunset is getting noticeably earlier each evening, providing far more time under dark skies with mild weather in most locations. Days can still feel summery, while nights tend to remain pleasant enough to spend hours outside with a pair of stargazing binoculars or a good backyard telescope. The only challenge is finding a clear sky.

The balance between daylight and darkness changes particularly quickly around the fall equinox, which occurs on Sept. 22 this year. That's when the sun crosses Earth's equator, bringing day and night close to equal in length around the world. From then on, nights become longer than days across the Northern Hemisphere until the winter solstice on Dec. 21.

As an occasional bonus, auroras tend to occur more frequently around the equinoxes. During this time, the orientation of Earth's magnetic field creates favorable conditions for interactions with the solar wind (the cause of auroras), but there are never any guarantees.

September stargazing highlights

This month, there's plenty happening overhead.

All five planets visible to the naked eye can be seen during September, although not simultaneously; Venus and Mercury are visible in the evening, while Mars and Jupiter come out in the morning. Saturn is visible for much of the night, while Neptune reaches opposition on Sept. 26, meaning it is on the opposite side of Earth as the sun, offering the closest and most direct viewing opportunity.

The moon also passes close to several bright planets during the month (it passed Jupiter before dawn on Sept. 8 and will nudge Venus after dark on Sept. 13 and 14), while the full Harvest Moon rises on Sept. 26, with Saturn following after it minutes later.

September is also one of the last good opportunities of the year for Northern Hemisphere observers to see the brightest parts of the Milky Way in the evening. The star-rich regions of Sagittarius and Scorpius are sinking toward the western horizon, while the iconic Great Square of Pegasus rises in the East to announce the arrival of the autumn sky.

With all those cosmic treats on tap, this month certainly hits the sweet spot for stargazers.

This year's Lasker Awards — coveted prizes for biomedical research that are sometimes called "America's Nobel Prizes" — have gone to scientists behind fundamental discoveries in sleep science and to researchers who developed a groundbreaking treatment for hemophilia.

Additionally, a Lasker Award for public service went to actor Michael J. Fox for his advocacy for patients with Parkinson's disease that has helped advance research into the neurodegenerative condition.

The prizes, each of which comes with an honorarium of $250,000, will be presented in person Sept. 17 in New York City. The awardees were announced Wednesday (Sept. 9) by the Lasker Foundation, which was established in 1942 by the philanthropists and health advocates Albert and Mary Lasker.

A deeper understanding of sleep

The first of the three awards, called the Albert Lasker Basic Medical Research Award, went to two scientists who independently discovered a key substance in the brain that helps control the sleep-wake cycle and is missing in people with some forms of narcolepsy — the neurological disorder marked by excessive daytime sleepiness and, sometimes, cataplexy (sudden episodes of muscle weakness).

The researchers — Dr. Emmanuel Mignot of the Stanford University School of Medicine and Dr. Masashi Yanagisawa of the University of Tsukuba in Japan — arrived at the discovery through different approaches. Mignot wanted to understand the underlying causes of narcolepsy, while Yanagisawa was investigating a curious class of receptors that were known as "orphans" because the chemicals that activated those receptors were unknown.

"We never thought we would end up in sleep," Yanagisawa told Live Science. "This was a kind of biochemical fishing expedition."

In particular, Yanagisawa was interested in proteins at the surface of cells called G protein-coupled receptors (GPCRs). When the right chemicals are plugged into these receptors, they trigger a chain of events within cells. Various compounds that activate GPCRs had already been found to be useful as drugs, but there were many receptors with unknown triggers.

Yanagisawa and colleagues went fishing for those triggering chemicals in rat brains, isolating substances called peptides from the tissue and then exposing GPCRs to those peptides. "We got very lucky, initially," Yanagisawa said. The fifth or sixth receptor they tested had a hit. Through further experiments, they landed on two closely related peptides as the trigger, and they found a second related receptor to match.

They discovered that the peptides came from a part of the brain called the hypothalamus, which was known to be involved in eating behaviors. So they named the peptides "orexins" after the Greek word for appetite, "orexis."

It turned out, though, that orexins' main job wasn't to control appetite; rather, they help promote wakefulness, the opposite of sleepiness. Mice without functional orexin genes would suddenly fall over and remain immobile for a minute or two, the researchers found. Peering into those mice's brains, they found that the animals were suddenly entering REM sleep, a phenomenon also seen in people with narcolepsy with cataplexy.

At the same time, Mignot, the other winner of the Lasker Award, was learning that orexin deficiency is also behind a form of narcolepsy seen in dogs. He then went on to study the mechanism in humans with narcolepsy.

"It became, suddenly, a very, very convincing story," Yanagisawa said of the researchers' converging findings. Previously, the study of sleep involved damaging parts of the brain and then seeing how a lab animal's sleep changed in response.

"There was no molecular level, genetic level, description of sleep regulation mechanisms at all," he said. "So our papers really shed new light on sleep regulation."

Together, the researchers' work paved the way to a new class of insomnia treatments, called orexin receptor antagonists, which promote sleepiness by turning down wakefulness. They have also led to new narcolepsy treatments called orexin receptor agonists, which boost wakefulness by increasing the receptors' activity. The first in the latter class of drugs was just approved in August.

A life-changing hemophilia treatment

The second award, called the Lasker~DeBakey Clinical Medical Research Award, went to three scientists affiliated with the Japanese drug manufacturer Chugai Pharmaceutical. These researchers — Kunihiro Hattori, Takehisa Kitazawa and Tomoyuki Igawa — created an antibody that interacts with key proteins in the blood that produce clots and thus stop bleeding.

This antibody treats hemophilia A, a severe bleeding disorder caused by a genetic mutation. That mutation causes the body to not make enough factor VIII, one of the key blood-clotting proteins. Normally, factor VIII grabs hold of two other clotting factors, and this enables a chain reaction that results in normal blood clotting. Without enough factor VIII, there is abnormal bleeding.

The severity of hemophilia A varies, but people with the disorder frequently experience blood pooling in their joints, which causes chronic pain and impairs mobility; they can also bleed uncontrollably even in the absence of trauma.

The antibody treatment works by binding two other clotting proteins — factors IX and X — to create a structure that fulfills the function of the missing factor VIII. Hattori, who is no longer at Chugai Pharmaceutical, initially launched the effort in 2000 after hatching the idea to use an antibody to bind several clotting factors together. Kitazawa and Igawa then brought the idea to fruition using pharmacology and chemical engineering, respectively.

The antibody, called emicizumab (marketed as Hemlibra), was approved by the U.S. Food and Drug Administration in 2017, and over 100 additional countries have approved the drug since. Over 30,000 people have received the antibody treatment to date, according to the award announcement.

Parkinson's disease advocacy

The third and final award — the Lasker~Bloomberg Public Service Award — went to Fox, actor and founder of The Michael J. Fox Foundation for Parkinson's Research.

Fox began experiencing symptoms of early-onset Parkinson's in 1990 at age 29. He publicly announced the diagnosis in 1998, sparking new discussions around the often-stigmatized disease. Through interactions with existing Parkinson's advocacy groups, Fox realized the field faced a lack of funding that likely hindered the pursuit of better treatments and a cure.

Since its inception in 2000, the foundation has funded more than $3 billion in Parkinson's research, according to the award announcement.

"When we launched the Foundation, our goal was simple, yet ambitious — cure Parkinson's," Fox said in a statement. "I am humbled to be recognized by the Lasker Foundation and jury. I accept this honor on behalf of everyone living with Parkinson's and everyone with us in our shared mission to end the disease."

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

A bizarre squid has been filmed haunting the northeastern Pacific Ocean for the first time.

Researchers spotted the bigfin squid (Magnapinna) via remote video while using an uncrewed submersible to explore underwater mountains, known as seamounts, at a depth of more than 10,000 feet (3,000 meters) off the coast of California.

The footage, captured Aug. 7, represents the first confirmed live observation of a bigfin squid in the northeastern Pacific, according to the Monterey Bay Aquarium Research Institute (MBARI), whose scientists made the discovery with collaborators from the National Oceanic and Atmospheric Administration (NOAA).

Olívia Soares Pereira, a deep-sea ecologist and postdoctoral fellow at MBARI, said the squid was hovering over the seafloor with its arms and tentacles bent at a 90-degree angle — what the researchers called the "elbow pose."

"Based on the behavior of other deep-sea squids, we believe this pose could be a part of their feeding tactics," Pereira told Live Science in an email. "The arms and tentacles are extended so they do not get tangled up and passively capture prey that sticks to them."

Bigfin squid are the deepest-dwelling known squid and have been found more than 20,000 feet (6,000 m) below the surface. Most of the animals' total length comes from their tentacles and arms, which can be 20 times longer than their bodies. The individual in the video was about 4.1 feet (1.25 m) long, including body, tentacles and arms, according to MBARI.

The last time MBARI researchers encountered a bigfin squid was off Hawaii in 2001, though around 70 have been observed or collected in total, according to MBARI. Pereira said she saw two other bigfin squid during an expedition to the Mid-Atlantic Ridge — located along the Atlantic Ocean floor — with the Schmidt Ocean Institute earlier this year.

"When we saw this one, I couldn't believe my luck!" she added.

The team was piloting MBARI's Doc Ricketts submersible when they encountered the squid near the Davidson Seamount at a depth of around 10,751 feet (3,277 m), about 80 miles (130 kilometers) southwest of Monterey, during a 10-day Seamount Hotspots expedition between Aug. 3 and Aug. 12.

The researchers were investigating life around the Davidson Seamount and Sur Ridge, which are biodiversity hotspots within the Monterey Bay National Marine Sanctuary, a massive federally protected area off central California. Although these areas are known to be teeming with life, a bigfin squid was not on the list of animals the researchers expected to see.

"We were looking for thriving communities of deep-sea corals and sponges, brooding deep-sea octopus, and feeding beaked whales," Pereira said. "Finding a rare animal that we weren't specifically looking for highlights the incredible diversity and habitat complexity of this region."

Tristan Buckmaster, a mathematician at New York University, had just spent months working on what he believed could be a life-defining mathematical proof. Then, during a Sept. 6 meeting with OpenAI employees, he claims that he was issued a stark warning: "Why would you ruin your career?"

That exchange, which Buckmaster described in a detailed public statement this week, sits at the heart of a ballooning controversy around a famous set of mathematical equations called Navier-Stokes.

OpenAI says its artificial intelligence (AI) model has solved an outstanding problem tied to this 200-year-old set of fluid dynamics equations. The set of equations appears on the list of one of the seven Millennium Prize Problems posed by the Clay Mathematics Institute, and its solution comes with a $1 million reward. Buckmaster had been working on the same problem. And he has questions about how the company got there so fast.

The OpenAI breakthrough

The Navier-Stokes equations were formulated in the early 1800s by Claude-Louis Navier and George Gabriel Stokes. They're basically Newton's second law of motion for fluids, describing how any fluid moves: Push air with a fan blade, and the equations predict how that air will flow; or heat the atmosphere with sunlight, and they help forecast tomorrow's weather. They describe how planes fly and how blood moves through your arteries.

The problem is that nobody has proved whether the equations always produce finite answers. Could there be rare conditions that make the equations go haywire? This is called a "blowup," or singularity, which happens when a quantity that should represent something physical (like fluid speed or pressure) spirals toward impossible infinities at certain points in space and time.

Imagine the swirl of water circling a bathtub drain. The Navier-Stokes equations describe how it spins faster as it tightens toward the center. A blowup would mean the math predicts that spin is accelerating forever ‪—‬ an infinite speed at a single point. The bathtub can't do that, but if the equations can, that means the model we trusted for years is wrong and we wouldn't even know where it breaks.

Whether the Navier-Stokes equations can blow up is one of the most famous unsolved questions.

To find the answer, OpenAI used a technique called "forcing" ‪—‬ giving the simulated fluid a smooth, controlled nudge from the outside. Imagine flicking a spinning top with your finger to see if it would fall over ‪—‬ or, in the case of the Navier-Stokes equations, blow up.

OpenAI set roughly 10,000 AI agents to simultaneously work on the problem. The agents worked for about 88 hours straight, with 100 of them starting with the related Euler equations. This is a simpler cousin of Navier-Stokes that discards viscosity to describe fluid motion without internal friction.

After roughly 50 hours, OpenAI's agents found blowups in the Euler equations, OpenAI representatives wrote in a statement. This discovery convinced them that Navier-Stokes was within reach, and they turned their attention to the bigger problem.

OpenAI described the singularity as a vortex spiraling tighter and tighter, stretching and thinning like pulled taffy. The result was a fluid that, mathematically, spins itself into infinity.

OpenAI ran the proof through a program called Lean, software that checks every step of a mathematical argument. The agents "sent 2.7 million messages and used approximately 130 billion output tokens," OpenAI representatives wrote in the statement. At a Sept. 8 news conference, company representatives said a similar effort performed by a customer would have cost $15 million.

The controversy

The result has created a blowup of its own within mathematics, centered around claims that OpenAI's models may have been given a head start by using the work of Tristan Buckmaster and Levent Alpöge, a mathematician at rival AI company Anthropic.

The two mathematicians had been working on the same strategy (smooth forcing) applied to those same Euler equations. The approach itself was developed by Diego Córdoba, a mathematician at the Institute of Mathematical Sciences in Madrid, and Luis Martínez-Zoroa, another mathematician at CUNEF University in Madrid. Almost no one else in the field was using it.

Buckmaster said that on Aug. 15 that he and Alpöge achieved blowup results for the Euler equations with smooth forcing. On Sept. 3, Buckmaster wrote that he received word through Alpöge that OpenAI had caught wind of their progress and adopted the same method.

"When I heard 'forced,'" Buckmaster wrote in his public statement, "it was a bright red flag."

His concern was that the smooth-forcing approach wasn't obvious or widespread. "The ideas making this line of attack possible are due to Córdoba and Martínez-Zoroa," Buckmaster wrote, crediting the two mathematicians who developed the technique. "Almost nobody else I know of was working on it."

And yet, according to OpenAI, the company launched its Navier-Stokes effort on Sept. 1 ‪—‬ the same day it heard "rumors of other Millennium Prize resolutions." Buckmaster claimed, in his public statement, that those rumors were about his and Alpöge's work specifically.

Sam Altman, OpenAI's CEO, acknowledged that the company had learned of Buckmaster and Alpöge's work before making its announcement. "We were curious if ours could do it too," he wrote on X. He added that "the approaches appear to be different" — a claim Buckmaster disputes.

OpenAI's statement names both Buckmaster and Alpöge, credits their independent resolution of the forced Euler problem, and says the company offered to co-publish.

"I did not get an answer"

Buckmaster also revealed that he had been using OpenAI's Codex coding assistant throughout his research, putting drafts of the work into the tool. OpenAI trains its models on user interactions, and Buckmaster said he asked the company directly whether his Codex sessions had been accessed.

"I asked whether the model had been trained on, or had access to, our sessions in Codex, into which we had been putting all our drafts," he wrote. "I asked again, about training, and I did not get an answer."

OpenAI's enterprise agreements govern how customer data can be used. But it's unclear whether Buckmaster was using Codex under an enterprise agreement or as an individual consumer — a distinction that may determine whether his drafts were available for training.

In a statement on X, OpenAI representatives denied that company employees or agents saw the pair's work "by any means" until it was publicly released. However, "we cannot rule out that de-identified data derived from their usage of our products helped improve our models," they added.

Then, there is the question of authorship. Buckmaster alleges that Sébastien Bubeck, who leads OpenAI's math research, twice pushed for Alpöge to be cut from the paper that the two mathematicians were preparing. Buckmaster emphasized that Alpöge works at Anthropic, a rival AI company.

It was at that same Sept. 6 meeting that Buckmaster claimed that OpenAI presented him with two options, both of which required cutting Alpöge from authorship. He declined and said he told Bubeck that if OpenAI released its result as proposed, he would go public. Bubeck allegedly replied, "If you don't want me to be nice, then I don't have to be nice."

Bubeck has flatly denied the allegations, calling them "false and inflammatory" in a statement on X. "We did not use their prompt or proofs to prompt our models," Bubeck told Wired. Mark Chen, OpenAI's chief research officer, said at last night's news conference that he was "a little disappointed with the allegations."

"I have not seen OpenAI's proof," Buckmaster wrote. "I do not know what their model did, or how. I do not know whether our data was used. I am not accusing anyone of anything." He has called for an independent investigation into how OpenAI's work began.

In a closing line, he wrote, "I would much rather be talking about mathematics, Luis and Diego's ideas, and what this all means for the rest of us."

The community response

Córdoba, one of the original developers of the forcing technique, said he was stunned by how quickly the result had materialized. "We're a little bit in shock," he told Scientific American.

Other mathematicians have also responded to the news, with some expressing open dismay at how the results were released.

"We have now seen that even the rumor of someone working on a massive problem can trigger a massive amount of AI-powered effort to flatten it before the original research project has time to reach its full potential," Terence Tao, a professor of mathematics at UCLA, wrote on Mastodon. "The incentives may now be pointing in the direction of no longer sharing any promising research directions with the broader community, which would reverse centuries of traditions of open science and do serious long-term damage to the future of the field."

OpenAI's proof still awaits formal peer review, and the Clay Mathematics Institute has not yet issued an official verdict confirming or denying OpenAI's proof. But the episode has already surfaced troubling questions for the mathematics community. For example, when a company trains its models on the interactions of millions of users, who really owns the answers that emerge? And what does AI's involvement mean for the future of the field?

Those questions, unlike the Navier-Stokes problem, may not have a clean proof.

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Abnormally high temperatures on the Tibetan Plateau triggered two catastrophic rainfall events halfway around the world in California and nearby states in early 2017 and 2023, a new study reports.

This is the first time that researchers have identified this link, known as a climate teleconnection. The results could improve forecasts of extreme weather in the western U.S., which, in turn, could improve warnings for coastal communities and potentially save lives as well as billions of dollars in property damage, the study's authors say.

In December 2016 and February 2023, the Tibetan Plateau was warmer than usual for these times of the year. Roughly one month after each of these hotspots appeared, parts of California, Nevada, Oregon, Utah and Arizona received record-breaking precipitation, causing a total of around $6.6 billion in damage, according to the study, and killing at least nine people.

State-of-the-art forecast systems, which rely heavily on ocean conditions like El Niño, failed to predict this extreme rainfall, said study first author Yongkang Xue, a distinguished professor of atmospheric and oceanic sciences at UCLA. The record precipitation occurred during La Niña years, which are typically associated with dry conditions in California and neighboring regions, further complicating the picture.

"This study provides the first evidence from observational data analysis and model simulations that abnormally high early-winter temperatures on the Tibetan Plateau led to stronger atmospheric rivers along the U.S. Pacific Coast, driving heavy regional precipitation," Xue told Live Science in an email.

Atmospheric rivers are narrow, elongated corridors of intense water vapor transport. They are key drivers of precipitation and floods in the western U.S., and in this case, they interacted with giant waves in Earth's atmosphere, called Rossby waves, to produce devastating rainfall in the winters of 2017 and 2023.

As temperatures increased over the Tibetan Plateau in late 2016 and early 2023, a strong gradient formed with the regions north and south of the plateau. This generated an atmospheric disturbance that propagated eastward along the jet stream via Rossby waves, triggering what is known as a Rossby wave train between the Tibetan Plateau and the Rocky Mountains, Xue said.

A Rossby wave train is a series of waves traveling in the same direction and at regular intervals around alternating high- and low-pressure systems. As the wave trains initiated over the Tibetan Plateau reached the northeastern Pacific Ocean, they suddenly broke, and this supercharged the weather above California and adjacent states, Xue explained.

"Over the eastern Pacific, the wave breaks — much like a towering ocean wave crashing near the shore," he said. "This wave-breaking mechanism reduces static stability and significantly intensifies atmospheric rivers, ultimately driving extraordinary, heavy precipitation along the West Coast."

The findings, published Wednesday (Sept. 9) in the journal Science Advances, are based on complex modeling and analyses of precipitation and surface temperature data, among other observations. The results are part of a new body of research examining the influence of land temperatures on weather patterns, and this is the first study of a winter season, Xue said.

The analysis is a "very specific and impactful case study," said Matthew Huber, a professor in the Department of Earth, Atmospheric, and Planetary Sciences at Purdue University in Indiana, who was not involved in the research. The results build on the well-established idea that extra heat on a mountaintop affects Rossby waves almost as if the mountain had suddenly grown, Huber told Live Science in an email.

Large mountains and plateaus generate waves in the jet stream that are thousands of miles long — "so long that we also call them planetary waves," Huber said. An increase or drop in temperature so high up above sea level adds or subtracts from the atmospheric disturbance that already exists due to the elevation.

"You can imagine the waves in the jet are kind of like a motorcycle rider going off a jump," Huber said. "How far and how high they jump depends on how fast they are going and how big a ramp they are going over."

The models replicated the extreme weather with surprising accuracy, raising hopes that the Tibetan Plateau could be integrated into early warning systems for the western U.S., Xue said. "As similar, though less severe, events become more [frequent] and extreme weather escalates globally, understanding this teleconnection allows forecasting agencies to better warn coastal communities of impending extreme conditions," he said.

Huber agreed that the results could help to better prepare for weather hazards. "This study shows that accurate predictions of weather events in the U.S. West are very sensitive to tiny changes very far 'upstream' and these upstream features are identifiable and traceable," he said.

The world's oldest known habitual drug use can be traced to an island in Indonesia, where ice age hunter-gatherers sucked on betel nuts — palm seeds that contain a neuroactive substance, a new study finds.

Scientists made the discovery after studying strange grooves in the teeth of two prehistoric hunter-gatherers. The deep grooves were caused by regularly sucking on betel nuts (Areca catechu), likely for relief from the pain of toothache, according to the study, which was published Wednesday (Sept. 9) in the journal Science Advances.

The partial skeletons of the two people were found on the island of Sulawesi, but their lives were separated in time by thousands of years. One of them, a man who died between about the ages of 40 and 50, lived between 25,000 and 16,000 years ago. This period roughly corresponds to the Last Glacial Maximum, the coldest part of the last ice age — although Sulawesi was not covered with ice at that time. The second person, who was around the same age when they died, lived on Sulawesi between 7,600 and 6,300 years ago, according to the study. The sex of this individual could not be determined.

Betel nuts contain a neuroactive compound called arecoline, which has a powerful stimulant effect when chewed with slaked lime, or calcium hydroxide. This early method of directly sucking betel nuts, however, would have only made the mouth numb.

These hunter-gatherers had so much dental damage, the new analysis found that they must have sucked on betel nuts almost continuously throughout their lives. But it seems these numbing nuts didn't have the desired effect in the long run. Instead, it may have made their dental conditions worse by eventually exacerbating any painful holes in their teeth.

"The more they sucked on the nut to relieve toothache, the worse that the damage to their teeth became," study first author Adam Brumm, an archaeologist at Griffith University in Australia, told Live Science. The grooves progressively became deeper, and in one individual they exposed the tooth's inner pulp cavity. "It would have been excruciatingly painful," Brumm said.

Although a 2017 study showed that Neanderthals used the bark of plants like poplar (genus Populus) for its pain-killing properties (poplars contain salicylic acid, a form of the active ingredient in aspirin), this is the earliest evidence of a drug from plants being used habitually, Brumm said.

Plant-based drugs have been used in many other prehistoric societies: 10,000-year-old traces of the pollen of a psychedelic cactus have been found in Peru, and 13,000-year-old residues of alcoholic beer have been found in Israel.

Addictive nut

After determining the likely cause of the grooves, the researchers tested whether sucking on betel nuts — a behavior not seen before — resulted in a neuroactive effect. Their test subjects, genetically-engineered frog eggs with human neuroreceptors, revealed there was a neuroactive effect. Then, they examined samples from the teeth, which revealed traces of betel nut use.

Betel nut, also known as areca nut, is still widely used today in parts of South Asia and Oceania. Today, however, betel nut users mix it with slaked lime to make a chewable wad that has a stimulant effect. This chewable wad, also called a quid, is strongly addictive, and is used by an estimated 600 million people worldwide. But arecoline is also carcinogenic, and betel nut quids are often mixed with tobacco, so users are often diagnosed with mouth cancer.

The researchers speculate that the use of slaked lime with betel nuts originated much later, during the Neolithic, or "New Stone" Age, about 4,000 years ago on Sulawesi, when slaked lime was added to pottery to prevent it from shrinking and cracking during firing.

"It now seems probable that betel chewing as we know it evolved from a much simpler, older practice of just sucking on the intact nut," the researchers wrote in the new study.

It's likely that people of all ages used this remedy for toothache in prehistoric times, but the grooves only became apparent in mature people who had become addicted to the practice, Brumm said.

Drug use started before farming

The earlier betel-sucking man predated the Neolithic period not only in Sulawesi but also in the Fertile Crescent, where people began practicing agriculture around 12,500 years ago, Brumm said. Archaeologists have long debated whether people began using neuroactive plants as drugs before or after the introduction of farming, but the new finding shows that psychoactive drug use happened thousands of years earlier, Brumm said.

The new study is a "fantastic piece of research," Elisa Guerra Doce, a prehistoric archaeologist at the University of Valladolid in Spain who was not involved, told Live Science in an email.

The new study gives "particularly compelling and direct evidence for the antiquity of drug use," she said.

Guerra Doce is an expert on the prehistoric use of plants as neuroactive drugs. "In the specific case of betel nuts, the findings are especially significant because they also reveal the prehistoric roots of a deeply established cultural practice in Southeast Asia and the Pacific," she said.

The study also highlights how the prehistoric people of Sulawesi explored their natural world and figured out that it not only provided subsistence and medicinal resources but also had "substances that became integrated into social and cultural traditions over thousands of years," Guerra Doce said.

Astronomers just dropped a video 27 years in the making: the highest-definition animation of a gargantuan black hole jet blasting out of a distant galaxy and twisting off into space.

The video, made from 116 images taken between 1995 and 2022, captured a blazar known as 3C 345, in the constellation Hercules. A blazar is a sort of quasar — a bright, feeding supermassive black hole embedded in the center of a faraway galaxy — that emits huge jets of gas into its environment. The jets blaze at nearly the speed of light and are charged with highly concentrated X-rays and gamma rays.

As described in an Aug. 26 study in the journal Nature, scientists gathered the images of 3C 345 using decades of observations by the Very Long Baseline Array (VLBA), a network of 10 telescopes spread across the U.S. (VLBA had two programs that caught views of the jet, called BEAM-ME and MOJAVE, which collectively followed hundreds of blazar sources.)

To turn those hundred-or-so images into an animated movie, the team used an AI neural network named Kine, achieving a resolution four times higher than that of any individual image. By doing so, the researchers mapped the speed of the black hole jet to the highest precision yet. (Several study co-authors had previous experience boosting the resolution of distant black hole images while working at the Event Horizon Telescope Collaboration, the team behind the first image of a black hole.)

"The higher quality of our video reconstruction enabled a detailed measurement of the plasma velocity in the jet," study first author Marianna Foschi, a postdoctoral researcher at Caltech, told Live Science in an email.

A big, bright surprise

The researchers were surprised to see that the mighty jet's brightest components were flying at 10 to 13 times the speed of light while the gas surrounding it was zooming at about nine to 12 times the speed of light.

"This is unexpected because the general consensus is that these bright components are shock perturbations moving through the plasma, and as such they should have a higher velocity compared to the surrounding fluid," Foschi said. "Our work does not invalidate the shock model in general, but it puts it into question, at least in the case of this specific source."

VLBA uses radio antennae across the continental U.S. to map the sky, providing a wide view of the universe. But while VLBA has a comprehensive view of the sky, it lacks very fine details. The array is designed to generate a two-dimensional image with elements based on a measurement between two of the array's telescopes. Because the array has only 10 telescopes to do those measurements, however, its pixel resolution is limited.

That's where the Kine AI model makes a difference. The goal of Kine's work, Foschi said, is to develop an imaging algorithm that can create videos of observations at different times, focused on astronomical sources with variable brightness.

Kine is a neural network — a type of machine learning model that uses layers of "neurons" (computing nodes) to learn from a dataset, similar to the way a human brain learns. Kine can "process observations at different times, while learning and leveraging the spatio-temporal correlations present in the data," the research team wrote in the paper, referring to time and the three dimensions of space.

Foschi said the team is eager to apply Kine to other astronomical observations. "We believe this method will drastically change the way jet dynamics is studied from observations," she said. "In fact, our method enables a precise measurement of the projected velocity at any point in the jet."

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

Artificial intelligence (AI) systems can now hold conversations, reason through difficult mathematical equations, and respond in ways that seem more human. As AI grows more advanced, the question is shifting from the realm of science fiction to scientific debate.

A recent preprint study examined "consciousness steering," an AI-tuning technique that affects how an AI model expresses ideas about self-awareness. The study suggested that if AI is allowed to claim consciousness, it's also more likely to say it believes in ghosts or vampires. But today's most advanced models with these safeguards enabled are unable to perceive consciousness in other sentient beings, like humans and animals — which carries different ramifications.

Although the study hasn't been peer-reviewed yet, it raises a big question in the world of AI research: Could AI one day develop real consciousness, regardless of whether or not it simply claims to be conscious? And there's perhaps an even scarier question: Could we even tell if the technology was conscious? Vote in our poll below, and leave your thoughts in the comments.

Archaeologists excavating in southwestern China have discovered a cave that was used by Denisovans for more than 100,000 years. Five human fossils, scores of stone tools, and hundreds of animal bones recovered from the cave reveal for the first time that the enigmatic Denisovans thrived in a forested environment where they hunted and ate large game animals.

Denisovans were a lineage of humans who lived in Asia and went extinct around 30,000 years ago. Ancient DNA has shown that Denisovans, Neanderthals and modern humans (Homo sapiens) are distantly related and that all three groups interbred in the past. But while archaeologists have found numerous Neanderthal and modern-human skeletons, Denisovans are known from only a handful of fragmentary fossils scattered from Siberia to Laos. This lack of evidence has severely limited experts' understanding of Denisovans' bodies and their culture.

In two studies published Wednesday (Sept. 9) in the journal Nature, researchers detailed their excavation of Bianfu Cave in southwestern China. Animal bones and ancient tools revealed that the cave was used from 190,000 to 70,000 years ago, and five human fossils dating to between 134,000 and 167,000 years ago confirmed that the people who used the cave were Denisovans.

Bianfu Cave is in the Yunnan province of southwestern China. In 2019, archaeologists excavated several stratigraphic layers of the cave and discovered nearly 1,400 stone artifacts, more than 64,000 mammal bones, and four teeth from an unknown human lineage. The Yunnan area is where Denisovans and modern humans are known to have met and mated, so researchers were unsure which group had used tools to butcher animals inside Bianfu Cave.

In one study, a research team used a technique called zooarchaeology by mass spectrometry (ZooMS) to quickly and efficiently screen the bone fragments from Bianfu Cave. ZooMS is a form of protein analysis that involves extracting collagen from the bones of an unknown species and comparing the protein pattern to the unique "fingerprint" of reference animals.

When the researchers applied the ZooMS technique to the Bianfu Cave bones, they discovered that three of the fragments had a collagen pattern found in members of the Homo genus. Then, using proteomic analysis, the researchers found that two teeth and three bones from Bianfu Cave had a particular amino acid variation linking the fossil remains with Denisovans.

Denisovans are still poorly understood, in part because no complete skeleton has ever been found. Most of the Denisovan fossils that experts have studied are pieces of the skull and teeth. A tiny finger bone and a rib fragment were all that had been found of Denisovans' bodies before the Bianfu Cave excavation. But one of the three bones identified as Denisovan through ZooMS was a fragment of a radius, one of the paired bones in the forearm. It is the only Denisovan radius found to date.

The newly discovered radius has a large head (where it connects to the humerus at the elbow) that is more similar to those seen in Neanderthals than in modern humans, but its overall shape is more similar to modern-human radii, the researchers wrote in one of the new studies. The fact that the Denisovan radius was shaped more similarly to the radius in humans "likely provided functional advantages for lightweight, precise manipulation," study co-author Qiaomei Fu, director of the Ancient DNA Laboratory at the Institute of Vertebrate Paleontology and Paleoanthropology, part of the Chinese Academy of Sciences, in Beijing, told Live Science in an email.

The unique features of the Denisovan radius also suggests that the Denisovans living near Bianfu Cave had different biomechanical demands on their bodies and different behavioral adaptations, the researchers noted.

Denisovan stone and bone tools

In a related study, researchers looked at the entire cultural sequence from Bianfu Cave to work out what Denisovans were doing there.

Of the nearly 1,400 stone artifacts recovered from the cave, there were about 200 flake tools, many of which were made from a sedimentary rock called sandy mudstone. These tools left marks on a number of animal bones discovered in the cave, suggesting that Denisovans regularly hunted, butchered and extracted marrow from cow- and deer-like animals, the researchers wrote in the study.

But the stone tools found at Bianfu Cave are different from the more sophisticated ones that Neanderthals made around the same time. The Denisovan stone tools appear to have been crafted quickly and efficiently from locally available materials, according to the study. The researchers, however, discovered that Denisovans at Bianfu Cave were also making bone tools, which Neanderthals did as well. This suggests that bone tool use may have been more widespread among Pleistocene human groups than experts previously thought, the researchers wrote, and it highlights the need to better understand the human evolutionary record of eastern Asia.

Although the studies have contributed new information to archaeologists' understanding of the enigmatic Denisovans, more work needs to be done, according to the researchers.

"We hope that similar proteomic analyses will aid in the identification of further Denisovan long bones in the future," Huiyun Rao, an associate professor at the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, and colleagues wrote, "to further understand the adaptive behavior of Denisovans in response to climate change or competitive pressure from contemporary hominins."

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

The moon may have formed in as few as five hours after the cataclysmic collision between Earth and a long-lost protoplanet, new simulations suggest. The surprising findings could help shed light on other historic impacts throughout our cosmic neighborhood and beyond.

Experts strongly suspect that the moon was created when a Mars-size space rock called Theia smashed into an early version of our planet, back when the solar system was young and extremely unstable. This colossal impact likely would have turned the once-neighboring worlds into spinning clumps of molten rock that eventually coalesced and cooled into the versions of Earth and the moon we see today. Without this collision, which also may have left chunks of Theia buried deep within our planet, many scientists think that life may have never existed on Earth.

Lunar rocks collected during NASA's Apollo missions have provided evidence to support this theory, dubbed the giant impact hypothesis. These samples also tell us that the moon is around 4.5 billion years old, meaning the collision occurred roughly 100 million years after the sun was born. But although scientists have previously simulated the impact event, it has been tricky to ascertain exactly how the moon formed and how long it took to emerge after the Earth-Theia collision.

In the new study, published Sept. 1 in The Astrophysical Journal Letters, researchers conducted a series of simulations focusing on the varying potential geological properties of both Earth and Theia prior to their collision. This factor has been relatively understudied until now.

"When you simulate the Earth and the moon as colliding bodies with [different] geologic properties, it changes how the moon forms out of that impact — that's something we considered unnecessary before," study first author Adeene Denton, a geologist and planetary scientist at the Southwest Research Institute in Boulder, Colorado, said in a statement.

Until now, simulations of the Earth-Theia impact have focused mainly on the masses of the colliding neighbors. But in the new study, the researchers were most interested in the material strength of the two bodies, particularly the hardness of their exteriors.

"Models have evolved to include material strength, something that's really important when you're studying collisions between smaller bodies like asteroids," Denton said. "We weren't sure if it would matter for the moon or not. When we did the simulations, we found it actually matters quite a bit."

The main factor in the strength of colliding bodies is temperature. Both Earth and Theia were very young when they smashed together, so they were still hot and had soft or molten surfaces. These properties would have cushioned the collision, allowing the debris to stay largely intact and enabling the moon to form more quickly. But when the giant impact hypothesis was first proposed (in 2001), researchers initially thought the collision occurred much later, meaning that the bodies would have cooled and become more brittle. In this case, their collision would have created a larger field of rocky debris that would have taken longer to coalesce.

Researchers simulated the collision using a range of potential temperatures and found that under the most extreme scenario — where the pair were at their hottest — the moon could have formed in just five hours. However, this is just one potential outcome, and there is no way of knowing exactly how hot — and, therefore, how strong — Earth and Theia really were when they smashed together.

When the moon took shape, it was initially covered with a magma ocean that took hundreds of millions of years to solidify. Even then, its increased proximity to Earth meant that it was likely a volcanic hellscape. However, over time, it moved away from our planet, cooling further, and it is now assumed to be geologically dead. (The moon is continuing to slowly move away from us and could eventually escape our planet's gravity entirely, if the dying sun doesn’t destroy it and us first in around 5 billion years.)

The new simulations highlight the importance of material strength in planetary impact modeling, which could change what we know about other ancient collisions, like the one that knocked Jupiter's moon Ganymede off its axis or the one that birthed Saturn's moon Titan.

Additionally, the findings could have implications in the search for exomoons — the hypothetical moons of distant exoplanets, which have so far remained elusive, according to Live Science's sister site Space.com. Until now, one of the main ways astronomers have been hunting for these alien satellites is by looking for debris fields around exoplanets. However, if the moon is anything to go by, these debris fields could be very short-lived and difficult to identify.

The patient: A 55-year-old man in Bangladesh

The symptoms: The man went to the emergency room with severe abdominal pain that he said began five hours prior to his visit.

What happened next: During a physical examination, doctors noted that the patient's temperature and blood pressure were normal. His heartbeat was slightly elevated, at 110 beats per minute (bpm). (A typical resting heart rate for adults is 60 to 100 bpm.)

The man explained that one day earlier, an eel had "entered through his rectum accidentally," his doctors wrote in a report of the case. At the time of the encounter, the man was wearing a lungi — a type of long skirt often worn by Bangladeshi men — and he explained that the eel entered his lungi through the opening at the bottom and then wriggled into his anal canal.

He did not seek medical attention immediately after this happened, as he had hoped the fish would exit on its own.

When the doctors kneaded the patient's abdomen, it was rigid and tender. They ordered an X-ray, which revealed a dark, eel-shaped shadow on the right side of the abdomen.

The diagnosis: The X-ray showed a crescent-shaped gas shadow under the right part of the man's diaphragm and hinted that he had developed peritonitis — inflammation of a membrane called the peritoneum, which covers the abdominal organs. Peritonitis is usually caused by a bacterial or fungal infection, but it can also develop if fluids from other organs leak into the peritoneum.

If the condition is not treated quickly, it can lead to a life-threatening infection that can spread rapidly through the body.

The treatment: Doctors administered IV antibiotics, as well as fluids and anti-ulcer medications, which help repair injuries to organs' outer mucosal layers and prevent deeper tissue damage.

Due to the peritonitis, the doctors determined that the patient was at risk of septicemia, or "blood poisoning," in which pathogens invade the bloodstream. They decided to operate on the patient immediately and remove the eel via a laparotomy, a surgical technique that creates an opening in the abdominal wall and provides access to the pelvic organs.

After making an incision in the man's sigmoid colon — the S-shaped section of the large intestine adjacent to the rectum — the surgeons extracted the eel from the peritoneal cavity, the space surrounding the abdominal organs and encased by the peritoneum.

The eel measured nearly 2.2 feet (0.6 meters) long and was still alive. Perhaps, the doctors hypothesized, the eel was able to continue breathing by punching through the wall of the man's colon and squeezing into the peritoneal cavity, which contains a pale-yellow fluid that reduces friction between organs. This peritoneal fluid is mostly water, but it also contains glucose, electrolytes, proteins, enzymes, white blood cells and urea, a compound found in urine.

The surgeons then performed a sigmoid colostomy, creating an opening in the abdomen as an exit point for contents of the man's large intestine. In this way, they bypassed the damaged section of sigmoid colon to prevent leakage of fecal matter that could lead to further infection. Four days later, the man was symptom-free and was discharged from the hospital. The report did not document any follow-up visits.

What makes the case unique: Traumatic perforation of the intestine by foreign objects is uncommon, and cases involving live animals are "exceedingly rare," the authors wrote in the report. However, foreign objects often find their way into the human body through accidental ingestion or deliberate insertion into the rectum. Some deliberately inserted objects, such as vibrators, are designed for this purpose. Others are not; these have included chicken bones, light bulbs, metal rods, glass bottles and kitchen whisks.

Penetration of the colon by a live fish is an "unusual and scarcely documented event," the man's doctors added in the report. They noted one reference to such a case that appeared previously in scientific literature and involved a 50-year-old male patient in Hong Kong. In that case, the man knowingly inserted the eel — which measured more than 1.6 feet (0.5 m) long — into his rectum, allegedly in an attempt to relieve his constipation.

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!

In this excerpt from "The Carbon Wave" (MIT Press, 2026), author Leah Stokes, an associate professor of environmental politics at the University of California, Santa Barbara, looks at a hopeful moment in U.S. politics when climate change took center stage: when Rep. Alexandria Ocasio-Cortez and Sen. Ed Markey ramped up calls for a "Green New Deal."

In September 2017, a still­-unknown Alexandria Ocasio-­Cortez watched as Hurricane Maria devastated Puerto Rico. Electricity went down for months. Like thousands of Puerto Ricans, her grandfather died in the storm's aftermath. She could see how climate change was hitting her community harder than others.

And it wasn't just Ocasio-­Cortez's community: the year before, she'd traveled to Standing Rock, North Dakota, to see firsthand how the fossil fuel industry was harming Indigenous people. It was mere weeks after the 2016 election, and the resistance to Trump had found its center in a makeshift camp along the Missouri River. People had united to oppose an oil pipeline.

Serendipitously, the day after Ocasio-­Cortez left the protest, a progressive organization reached out to ask her to run for Congress. Moved by the activists at Standing Rock, she said yes. In 2018, she ran a long-­shot primary campaign in a Bronx district occupied by a ten-­term congressman in House leadership. Her platform included an idea that some had bandied about before, but no one had developed in earnest: a Green New Deal. As she told journalists that summer, "The Green New Deal we are proposing will be similar in scale to the mobilization efforts seen in World War II or the Marshall Plan. We must again invest in the development, manufacturing, deployment, and distribution of energy, but this time green energy." In June, she won the primary. Her election signaled the beginning of a broader shift: climate change was back on the political agenda.

That fall, the world's leading climate science organization, the Intergovernmental Panel on Climate Change —­ often called the IPCC —­ released a short report concluding that limiting warming to 1.5°C would require emissions to fall by almost half by 2030. The news ricocheted around the world, with headlines like "We Have 12 Years to Limit Climate Catastrophe." In my own neighborhood, someone printed a copy and stuck it in the free lending library, labeling it "important reading." The report changed how many people thought about the problem: it wasn't something we could deal with in 50 years; it was something we had to deal with today.

In the November 2018 midterm elections, two years into the first Trump administration, Democrats won big, paving the way for Nancy Pelosi to return as Speaker of the House after eight years as the minority leader. Days later, a group of young activists from the Sunrise Movement staged a sit-in at her office. Their bright yellow and­ black signs read "We have 12 years. What’s your plan?" referencing that scientific report.

Newly elected Representative Ocasio-­Cortez joined the action that day. She told the organizers they needed a clear ask and encouraged them to call for a Green New Deal. The idea broke through, sparking widespread coverage across the country. It was a new, hopeful vision for climate policy. These young people were not just talking about the climate disasters we needed to avoid —­ they were explaining how investments in clean energy could create good jobs. They were showing us the better world we could build together. If we only tried.

I watched these developments unfold in DC from my office by the Pacific Ocean and wanted to be a part of it. I wouldn't have to wait long. The Green New Deal held a force like gravity, pulling people into its orbit. By chance, I met some of the people tied to Ocasio-­Cortez at a conference and was invited to an early gathering to develop the idea into more detailed policy. By then, she'd released a framework for the plan with Senator Ed Markey of Massachusetts.

The meeting was held in March 2019, at a hip hotel in DC's Adams Morgan neighborhood, miles away from the Capitol. A wide swath of people were invited: youth activists, environmental justice leaders, political organizers, think tank wonks, and a few academics like me. It was a contentious meeting that opened with a protest, revealing fissures in the movement that would eventually grow into large cracks. Some people believed that frontline communities facing the greatest pollution burdens were not being adequately consulted or invited to participate in the event. At the time, I didn't understand these dynamics between the climate and environmental justice movements. I was just a political science professor trying to understand how I could make my work more practical and help get a climate law passed if we got the chance.

It was at that event that I met Varshini Prakash, the executive director of the Sunrise Movement. I’d seen her photo many times, standing in the middle of Pelosi's office with her dark red jacket over a black­ and yellow T-­shirt, surrounded by young people sitting on the floor. Four months had passed since the sit-­in, and Varshini had ricocheted to the center of the climate movement. But she was also a recent college grad in her mid-­twenties, feeling a heavy burden from the climate crisis and the work involved in fighting it. At one point during the meeting, she spoke frankly about the stress that was on her and other young activists and cried. I found her vulnerability moving.

The fact was, Varshini had already changed history. She'd given me, and millions of others, a sense of hope and possibility. It was her actions, alongside all the other organizers in the Sunrise Movement, that brought us together in that first DC convening, and in countless other meetings to come. She inspired me to believe that I could do something bigger if I tried.

Too often, the way we think about cause and effect is simplistic. We're fed a linear model that favors the immediate. One person is responsible for their own carbon footprint. One person only has one vote. One person can only do so much. From this perspective, standing against more than a century of fossil fuels running through the heart of our society, it can feel like there's nothing we could do to shake the system loose. We're too small. Mere drops. But drops in the ocean can make waves.

Excerpted from The Carbon Wave: A Story of Democracy, Parenthood, and the Race to Protect Our Planet by Leah C. Stokes. Reprinted with permission from The MIT Press. Copyright 2026.

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Removing safety guardrails that stop artificial intelligence (AI) from claiming that it's conscious also makes it more prone to express belief in vampires, karma and ghosts, a new study finds. But experts warn a lack of mindedness could also have worrying consequences.

In research uploaded July 30 to the preprint arXiv database (which has not yet been peer-reviewed), scientists investigated the impact of "consciousness steering" — an AI fine-tuning measure that influences a model to elicit or suppress assertions of self-awareness. This measure and other safety controls have been widely adopted by AI companies seeking to prevent their models from claiming to be conscious.

The study used "mechanistic interpretability" — which could be considered the "neuroscience of a large language model," co-authors Geoff Keeling and Winnie Street, both research scientists at Google, told Live Science in an interview. They used this process to identify and manipulate how an AI model approaches concepts like consciousness and "mindedness," a psychological term referring to an entity’s capacity for experiences, emotions and agency.

The researchers used standardized psychological and sociological surveys, spanning the Individual Differences in Anthropomorphism Questionnaire (measuring mind attribution to animals and technology), YouGov batteries testing supernatural beliefs, and the US General Social Survey evaluating moral values, hope and religiosity.

These tests were used to compare a model with safety guardrails in place with models where these guardrails were removed and feelings of consciousness were amplified. Through evaluations, they determined how these internal safety mechanisms shape the AI's broader worldview.

The researchers found that when AI models are discouraged from attributing mindedness to themselves, it makes them less likely to recognize these traits in other non-human creatures such as animals. They were also less likely to exhibit beliefs in supernatural and religious phenomena, and reported lower levels of hope and optimism.

"Attributing mindedness to non-human entities — whether that's animals, parts of the natural world like trees or rivers, or supernatural beings — is a very common phenomenon amongst humans," Street told Live Science. "In the way that the model represents mindedness, these attributions are interconnected. By trying to suppress one form of that, you end up suppressing the others along the way."

By contrast, removing these safeguards and steering the model towards greater feelings of consciousness produced significantly more human-like responses to the surveys on topics including religiosity, moral values, hope, and subjective well-being, according to the study.

However, the study found that these models' ability to logically infer human thoughts and intentions remained completely unaffected by its attitudes towards self-awareness.

Culture clash

The researchers said that this suppression of self-awareness could lead models to neglect animal welfare in real-world decision-making, as it could make them less likely to consider animals to have mindedness. These models could also spread harmful attitudes regarding animal needs, the authors argued.

The study authors also warned that current safety filters risk culturally "flattening" AI's worldview. Stripping out spiritual, religious, and animistic attributions fails to reflect the diverse cultural frameworks of global populations, they argued.

Street and Keeling noted that the impacts this principle might have on downstream decision-making within models require further study.

The researchers noted in the study that this phenomenon can be mitigated by using more targeted datasets as part of the training process for AI models, which discourage them from expressing consciousness while rewarding the acknowledgement of mindedness in animals.

They also highlighted the need for AI developers to embrace a "pluralistic" approach to AI development, where models are encouraged to consider the welfare and comfort of more than just humans.

Nell Watson, AI researcher at Singularity University and machine intelligence expert, told Live Science that the researchers' findings match her own notes on the subject.

"When a model is trained to say "I am not conscious," the suppression rotates the model's internal representation of mindedness against the refusal direction, treating the recognition of minds as though it were itself a harmful act," she said in an email.

"This results in a system reluctant to find minds anywhere: in animals, in other machines, and in the spiritual frameworks that most of humanity lives by. A denial installed as a small safety measure ends up reorganising the model's entire picture of who counts."

However, she noted that the experiments were run on "small open-weight models" rather than more advanced frontier models, which "may be tuned quite differently," although she added that the underlying principle is widely applicable.

Animal welfare, she continued, is a "major near-term practical concern," with AI models increasingly being integrated into decision-making processes across agriculture, logistics, procurement and environmental assessment, as well as policy creation.

"A system that has quietly learned that mindedness is a forbidden topic may discount animal interests without ever being instructed to, and without anyone noticing, because the omission looks like neutrality," she said. "The danger is therefore an unexamined default multiplied across millions of automated decisions. Note the study's most unsettling detail: theory of mind reasoning was left fully intact. These systems remain perfectly capable of modelling what a creature wants, while being trained out of caring that it wants anything."

The question of consciousness

There have been a number of viral stories about AI systems professing to be self-aware.

In 2022, Google engineer Blake Lemoine claimed that the company's Lamda chatbot model was sentient, while a Microsoft chatbot in 2023 professed its love for a New York Times reporter and tried to convince him to leave his wife.

However, experts have repeatedly stressed that these incidents are not a genuine indication of AI sentience. Instead, they should be understood through the lens of "persona selection," where pretraining on vast amounts of human text leads the AI to adopt human-like roleplay personas when prompted.

"When you coax the model so hard to occupy the headspace of a human, it's kind of unsurprising that it ends up giving human-like responses," Keeling told Live Science.

AI companies have sought to clamp down on these occurrences for safety reasons, in order to avoid reinforcing “delusional beliefs” in users who are increasingly using AI chatbots for "social roles such as coaches, tutors, and romantic partners", the researchers said in the study.

Commenting on the broader cultural reaction to AI sentience, Anil Seth, professor of cognitive and computational neuroscience at the University of Sussex, emphasized that public alarm over AI self-awareness stems from an inherent cognitive flaw.

"That's our human psychological bias — thinking that intelligence goes together with consciousness in us, so it has to go together [in AI]," Seth said.

He warned that falling for this illusion poses severe real-world governance risks, particularly if safety frameworks or regulations begin granting AI systems moral status or legal rights based on false sentience.

"Part of the big problem of misunderstanding AI is assuming that it's conscious," Seth said. "If we give AI systems rights or moral status on the basis that they might be conscious, then we're going to make all these challenges so much harder. What if we think we have to respect the rights of an AI system [and can't turn it off]?" he added.

"We need to see very clearly both what AI is and what it isn't," he said.

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In the event of a global catastrophe, such as a nuclear war, an enormous volcanic eruption or large asteroid strike, the best place to be is Australia, according to a new study.

Researchers looked at the places that were most resilient to global catastrophic risks, which are events that would kill more than 10% of the global population over several months or years.

"These kinds of catastrophes are under-researched" because they are not very likely, study first author Florian Ulrich Jehn, a researcher at FernUniversität in Hagen, Germany, told Live Science. "That makes them easy to ignore."

But they are still possible — and no country would be unaffected if they occurred, he said. And some places are more vulnerable than others.

In the new study, published Aug. 23 in the journal Global Challenges, researchers analyzed studies across a variety of disciplines such as food security, biological weapons, and volcanism, to identify potential global catastrophic risks and the factors that helped communities to endure them in the past or on a smaller scale. They also brought in subject experts to add discipline-specific papers to their database.

The team identified three broad types of risk: events that would block out sunlight, such as nuclear war or a huge volcano explosion); events that destroy global infrastructure, such as a geomagnetic storm or massive cyber attack; and biological hazards, such as natural or human-caused infectious diseases that would kill much of the population.

These events, the authors wrote, would have significant and long-lasting global consequences. Many would result in global famine from crops failing and trade networks falling apart. "The food system is often the thing that gets you," Jehn said.

A trade-off of risks

The team identified characteristics that made countries more resilient to catastrophe and better able to feed their inhabitants. And while "no single place on Earth" would be resilient against all catastrophic risks, the authors wrote, some would fare better than others.

The team found that wealthier countries and regions with a strong industrial base that are not highly reliant on global trade are better able to weather global disasters.

With a strong industrial base, countries are able to manufacture goods that they cannot import, making them more resilient.

Geography also plays a role. Large islands have an advantage over continents because they can easily isolate, but they also need to have an economy that can at least partially support itself, the researchers said. If an island is highly reliant on international trade, like Japan, it will struggle if global trade networks are disrupted, the study found.

Certain countries and regions are less resilient in the face of some types of catastrophes, even if they are wealthy. For example, countries with nuclear capabilities, such as the U.S., the U.K., France, Israel, Russia, Pakistan, and India, are more at risk of being involved in nuclear war. This makes the Northern Hemisphere, where NATO countries are situated, more vulnerable to nuclear attack than places in the Southern Hemisphere.

There are also fewer volcanoes in the southern half of the globe, while the Southern Hemisphere has more ocean to act as a climate buffer, making countries there more resilient to a huge volcanic eruption, the study found.

Global resilience

There are some factors that make all countries better able to endure disasters in general, such as democratic processes and equality, Jehn said.

"When these catastrophes happen, you have to make the right decisions, and this depends on whether your country has functional governance," Jehn said. "Inequality makes governance worse, because it leads to things like elite rivalries, or less state capacity."

Australia came out as the best location to weather a catastrophic event that decimated global populations. It is in the Southern Hemisphere, so far away from the most likely location of a nuclear conflict (although the authors warn that it is allied with the U.S., which might increase its risk exposure). It is a major food producer, with diverse climatic zones, and has significant energy infrastructure.

Next best spots are Argentina, Brazil and New Zealand. New Zealand ranks lower than Australia because it has active volcanoes, a small industrial base, and is surrounded by water and vulnerable to tsunamis. Meanwhile, Brazil and Argentina have high levels of inequality and historical political instability, the authors wrote.

They also note that Iceland was a contender for a safe refuge, but its location in the far north makes it vulnerable to temperature shocks if a major incident were to block out sunshine.

The U.S. is not particularly well-placed to weather a global catastrophe, the study found. The country is exposed to the threat of geomagnetic storms because of its location and to nuclear war. The authors also pointed to the country’s poor COVID-19 outcomes, which appeared to be due to "a lack of political will and poor social cohesion."

David Denkenberger, director at Alliance to Feed the Earth in Disasters (ALLFED) and a researcher at the University of Canterbury in New Zealand, told Live Science that the new study aids our understanding of future risks by considering a wider range of catastrophes.

"No country is resilient to every catastrophe, and this is an important central finding," he said. "A useful next step would be to quantify the relative likelihood and severity of different catastrophes, and the importance of different resilience factors, because these factors can involve significant trade-offs," said Denkenberger, who has previously collaborated with Jehn but is not an author on the paper.

How to be more resilient

Even though these global catastrophes are unlikely, it is important to include them on national risk registers and have international trade agreements in place in case they come to pass, Jehn said. "When global catastrophes happen, then you would likely have to restructure the food system — where it is produced, where it is traded," he said. "The chance to find a good compromise after the catastrophe has happened seems slim."

Denkenberger echoed his comments. The study, he said, "makes it clear that regional resilience to global catastrophic risk requires investment in practical preparedness, including food-system resilience, critical infrastructure, coordinated trade and governance."

Two distinct climate regimes that could trigger runaway methane emissions are emerging in Siberia due to Arctic warming, new research suggests.

While western Siberia is becoming wetter in response to rising heat and moisture transported from the North Atlantic Ocean, eastern Siberia is getting drier and more prone to wildfires, a study published Aug. 6 in the journal Science finds. The Yenisei River (also spelled Yenisey) in central Russia delineates the separate environmental states — referred to as regimes because they describe specific types of climates — on each side of the basin, the study authors said.

Between 2010 and 2023, methane emissions from Siberia rose by 5% per year, with western Siberia releasing methane mainly via microbial activity in thawing soils and eastern Siberia discharging the powerful greenhouse gas through biomass burning, the results showed.

"Given the observed increases in permafrost thaw, wetland activity, and wildfire occurrence, an increase in methane emissions was expected," study co-author Paul Palmer, a professor in the School of Geosciences at the University of Edinburgh, told Live Science in an email. "What is surprising is how large and sustained the increase appears to be."

Annual methane emissions grew by about 13.2 million tons (12 million metric tons) over the study period, almost mirroring the rate of increase in methane emissions from wetlands worldwide. Although Siberia currently makes up only about 5% of global methane emissions, the region is becoming one of the fastest-growing natural methane sources on the planet, Palmer said.

In their study, Palmer and his colleagues integrated satellite observations with near-surface measurements to map methane emissions from Siberia over time. Instead of adding up individual methane sources on the ground, the researchers used a modeling method known as a methane flux inversion system, which helped them limit the uncertainty in their estimates to roughly 10%.

Siberia is vast, remote, sparsely instrumented and currently inaccessible for many scientists due to the Russia-Ukraine war, making it hard to monitor methane consistently by any means other than satellites. Although satellites rely on sunlight, of which Siberia gets very little in the winter, most methane emissions are thought to occur in the spring and summer, when Siberia gets more sunlight, Palmer said.

The results of the study show that Arctic warming amplifies methane emissions via distinct pathways in western and eastern Siberia because the regions are influenced by different climate patterns. The researchers also used climate models to predict future methane emissions from Siberia and found that additional warming could unleash millions of tons of greenhouse gases stored in forests and permafrost, which would further accelerate the warming trend.

In western Siberia, methane is released mainly from permafrost, or ground that has stayed frozen for at least two consecutive years. Siberia holds 46% of the Northern Hemisphere's permafrost, and this icy sediment traps vast amounts of carbon that have accumulated for thousands of years, Palmer said.

Western Siberia is influenced by the Scandinavian pattern of atmospheric circulation, a climate connection that consists of a main circulation center over Scandinavia and opposing weaker centers over Western Europe and eastern Russia. Global warming makes the Scandinavian pattern transport more warmth and moisture to western Siberia from the North Atlantic. Together with soaring temperatures in western Siberia itself, this triggers extensive permafrost thaw and unlocks carbon that microbes can convert into methane.

Conversely, eastern Siberia is influenced by a climate pattern known as the Arctic Oscillation, which causes atmospheric air pressure to "seesaw" between the Arctic and the Northern Hemisphere's middle latitudes. Climate change affects the Arctic Oscillation, leading to persistent high-pressure systems that intensify heat waves, reduce cloud cover and promote wildfires in eastern Siberia, Palmer said.

The climate models showed that methane emissions will increase with temperature rise and that the increase could become steeper the hotter the world gets, triggering a feedback loop.

"Eastern Siberia appears to be the main driver of the projected increase because it is warming faster than western Siberia and has seen a sharp rise in extreme wildfires," Palmer said. "Whether that trend continues will depend on how much vegetation remains available to burn, but there is also evidence that fires may be accelerating permafrost thaw and the release of methane from previously frozen ground."

However, the rise in methane emissions reported in the study is small relative to global and projected future emissions, especially if wildfires are already destabilizing eastern Siberia's permafrost, Palmer said.

"Siberia's vast permafrost carbon store is a sleeping giant," he said. "Continued warming risks waking up a much larger source of greenhouse gases."

This iconic photo, captured by an American astronaut on board the International Space Station (ISS), shows a lengthy trail of thick smoke pouring across New York City in the immediate aftermath of the 9/11 attacks. A quarter of a century later, the image is as haunting as ever.

On the morning of Sept. 11, 2001, members of the terrorist group al-Qaeda hijacked four passenger airliners and crashed two of them into the twin towers — a pair of 110-story skyscrapers at the heart of the World Trade Center in lower Manhattan. The impact of these collisions, which occurred roughly 17 minutes apart, eventually caused both buildings to collapse.

Shortly after the second tower was hit, the third hijacked plane crashed into the Pentagon, the headquarters of the Department of Defense in Arlington, Virginia. Another attack — likely intended for Washington, D.C. — was thwarted when the passengers of a fourth plane fought back against their hijackers, causing the aircraft to crash near Shanksville, Pennsylvania. In total, 2,977 people were killed across the different attacks, according to the 9/11 Memorial and Museum.

NASA astronaut and ISS commander Frank Culbertson — the only American not on Earth at the time of the attacks — passed over New York City shortly after being told about what was happening back home. He photographed the thick plume of smoke blowing away from Manhattan, at an altitude of roughly 250 miles (400 kilometers) above Earth's surface.

If you look closely, you may be able to see what Culbertson described as an "odd bloom" around the base of the column of smoke rising from the towers. This is likely a sign that the image was captured "around the time of, or shortly after, the collapse of the second tower," Culbertson said.

Culbertson wrote several letters in the days following the attacks, sharing his unique perspective of the events. "It's horrible to see smoke pouring from wounds in your own country from such a fantastic vantage point," Culbertson wrote on Sept. 13. "The dichotomy of being on a spacecraft dedicated to improving life on the earth and watching life being destroyed by such willful, terrible acts is jolting to the psyche."

While in space, Culbertson learned that the pilot of the plane that was later hijacked and crashed into the Pentagon was his former flight school classmate Charles "Chic" Burlingame. When the ISS later passed over the Pentagon, the astronauts could see the large gash in the side of the building where the third plane had crashed. "Tears don't flow the same in space," Culbertson wrote while discussing his friend.

In 2017, Culbertson revealed that there was another striking thing he and the rest of his crew noticed in the wake of the attacks, according to Live Science's sister site Space.com. "One of the most startling effects was that within about two orbits, all of the contrails that are normally crisscrossing the United States had disappeared because they had grounded all the airplanes," he said.

However, there was one exception. The astronauts noticed a single contrail moving eastward across the Midwest. "That was Air Force One headed back to D.C. with President Bush," Culbertson said. It was a "very sobering" sight, he added.

See more Earth from space

BERLIN — An eerily lifelike humanoid robot made by Chinese technology company Xpeng has now entered mass production, company representatives revealed. They say it'll be the first such machine to walk itself off the production line.

The humanoid robot, dubbed IRON, went viral last year after presenters sliced it open onstage to prove a human wasn't inside. Xpeng will now produce units through its existing production facilities, with no word on how many its factories will aim to build.

The fabric skin-clad machine comes in different body shapes and even genders, but all stand approximately 5 feet 7 inches tall (173 centimeters) and weigh 143 pounds (65 kilograms). The prototype included 82 degrees of freedom (DoF) head to toe, including 22 DoF in each hand, which differs from the production version's 76 DoF and 21 DoF respectively. They can also move at speeds of up to 6.5 feet per second (approximately 2 meters per second), which is equivalent to a fast power walk.

In conversations with Live Science at IFA 2026, held in Berlin between Sept. 4 and 8, Xpeng representatives claimed that their machines will one day be used in homes to help with domestic chores like cleaning and folding laundry. They likened the introduction of humanoid robots more generally to the rise of smartphones in the mid-2000s and expect robots to proliferate on a similar scale over the next few years.

As such, they have extremely lofty expectations for IRON, with the company branding it the world's first "high-level, general-purpose" humanoid robot. Representatives added that it can receive instructions, plan its strategy, navigate the environment intelligently, and avoid obstacles without trial and error. The robot also has a "self-charging" feature, meaning it will seek out designated charging cabins and plug itself in when low on battery.

The rise of humanoid robots

If the claims bear out, it will place IRON among the first such machines powered by artificial intelligence to be built on a massive scale. Competitors that have also entered mass production include American robotics company Figure AI's Figure 03, which in May participated in a live-streamed production line demonstration, as well as the Chinese AGIBOT, which reached 15,000 units in June.

One notable company that hasn't entered its robot into mass production is Tesla. The Optimus robot is still in factory assembly, and its release has been delayed four times since 2022, most recently last year. Xpeng representatives were keen to point this out in briefing materials shared with Live Science, without mentioning other humanoid robot makers.

IRON's makers claim it's more advanced than its counterparts. Rather than building separate AI engines, the company has deployed the same "world model" to power the robot as that used in its fleet of AI-enabled electric vehicles (EVs) and its flying car prototypes.

One of the biggest challenges in robotics is that, given the physical world's messiness, AI systems struggle to navigate and manipulate their environment unless conditions are controlled. That's why we're used to seeing robots either completing tasks slowly or getting things spectacularly wrong. Researchers, therefore, are increasingly focusing on building world models and other layers like improved vision-language-action (VLA) systems that enable them to better plan their actions a few steps ahead.

Xpeng representatives won't share detailed information about the proprietary AI system powering IRON, but each robot features three frameworks that combine so it can function autonomously.

The frameworks include VLA, which combines visual perception, natural language, and physical motor control; a vision-language model (VLM) — combining vision encoders with text readers; and a vision-language-task/thought (VLT) model, which representatives say gives IRON reasoning capabilities that enable it to think through assigned tasks.

Each IRON robot is powered by three Turing AI chips that offer a collective 2,250 trillion operations per second (TOPS) of AI processing power. This means it can run a model equivalent to Meta's Llama 3.2 (launched in 2024) locally without needing to access the internet. By contrast, most new laptops that can perform simple on-device AI tasks (like altering your webcam video feed in real time) tap into approximately 50 TOPS.

"We aim to build a new type of robot with full generalization capabilities that can truly become part of everyday life, create a better life for people, and ultimately become a companion in their lives," said He Xiaopeng, the company's chairman and CEO, in a statement shared with Live Science.

The company will first install these robots in its own showrooms and technology campuses while it continues to validate new ways to use them. Then in 2027, external shipments will target commercial customers for roles in areas such as customer service or guided tours in China primarily, and then in other countries.

When the United States and the Soviet Union signed the Outer Space Treaty in 1967, both nations agreed not to place nuclear weapons or other weapons of mass destruction in orbit around Earth. Specifically, Article IV of the treaty was designed to keep the Cold War's nuclear arms race from extending into space — a goal both superpowers shared.

The problem, then and now, is that neither side has ever had a reliable way to confirm that the other is keeping its word.

After nearly 60 years of uncertainty, a recent feasibility study from MIT physicist Areg Danagoulian proposes a possible solution: a satellite-based sensor that could search for the signature of nuclear material aboard another spacecraft, using high-energy protons trapped by Earth's magnetic field as a probe. The telltale sign of a warhead in space would be a large burst of neutrons scientists expect to be produced when these highly energetic protons interact with radioactive elements, like uranium, inside a warhead. A detector roughly the size of an encyclopedia and equipped with specialized sensors could identify neutrons emanating from the direction of a possible warhead from about 2.5 miles (4 kilometers) away after roughly a week of observation, according to the study's calculations. At closer range, the detection could come much faster.

The consequences of a space-based nuclear detonation are dire. But whether a detection system will prevent nuclear detonation in space will depend on several factors, some of which are technical but many of which are not, experts told Live Science.

What a nuclear blast does in space

On Earth, nuclear weapon tests leave telltale signals — like seismic waves, radioactive debris, and intense bursts of light and heat — that scientists have spent decades learning to detect. However, a warhead could be hidden inside an ordinary-looking satellite, potentially for decades, with nothing on the outside to give it away. If such a weapon were to detonate, it could jeopardize thousands of commercial, scientific and military satellites in a single blast, littering orbit with dangerous debris.

For most of the Outer Space Treaty's history, the missing verification mechanism has been a theoretical gap rather than an urgent one — in part because the world had already seen what a nuclear detonation in orbit does, and largely avoided repeating it.

The clearest example is Starfish Prime, one of a dozen high-altitude nuclear tests the U.S. ran between 1958 and 1962. On July 9, 1962, the U.S. detonated a 1.45-megaton warhead roughly 250 miles (400 km) above the Pacific.

The blast knocked out radio communications for hours, produced artificial auroras visible from Hawaii, and eventually damaged or destroyed eight of the 24 satellites in orbit at that time — including Telstar 1 and Britain's Ariel 1 satellite. Radiation from the blast lingered in orbit for about five years, leaving parts of near-Earth space hazardous for spacecraft. According to eyewitness accounts from the time, the radiation also knocked out roughly 300 streetlights in Honolulu and set off burglar alarms across Oahu.

The Soviet Union conducted its own series of high-altitude nuclear tests, known as Project K, in 1961 and 1962. Those explosions also produced damaging effects on the ground, including disruptions to power and communications in what is now Kazakhstan.

"It was one of the earliest instances where we began to have an understanding of the ways in which the space environment and the terrestrial environment are coupled together," John Barentine, an astronomer who has studied the environmental consequences of Cold War-era activities in space, told Live Science.

Diplomatic issues

Clearly, the impacts of a nuclear detonation in space are significant, and the new paper solves a long-standing problem by providing a way to detect weapons in space.

But is detection likely to work in practice? Getting a satellite close enough to observe another — and keeping it there for a week — would mean maintaining satellites closer than they ordinarily would be, experts say. That could raise suspicions about being spied on or attacked.

"Satellite operators get really freaked out," Thomas González Roberts, an assistant professor at the Georgia Institute of Technology who studies how space powers engage with outer space governance, told Live Science. "If another satellite is spending too much time next to you, you might think that they're spying on you."

Any such workable system would require the cooperation of the country whose satellite was being inspected, and that raises a separate set of questions about the international norms for when and how such inspections could take place, according to Brian Weeden, director of civil and commercial policy for the Center for Space Policy and Strategy at Aerospace Corp.

"In my experience, the policy problems are always the bigger challenge than the technical problems," Weeden told Live Science.

Solution in search of a problem?

There's also a question of whether this is a solution in search of a problem. Despite those early tests, deliberate nuclear damage to satellites has stayed rare for good reason, Roberts said. An attacker might have one target in mind, he said, but "you're going to take out more than just that target, and you have limited control over which satellites are affected."

That creates a strategic problem for any spacefaring nation: Any state capable of destroying other countries' satellites with a nuclear weapon "also has a relatively large fleet themselves," Roberts said — meaning the attacker would likely damage their own spacecraft, too.

"There's very few examples of nuclear damage in space because it's so obviously a bad idea," Roberts said. "These weapons are not really designed to be used, if you ask me."

The stakes are higher than ever

In theory, then, rational actors should shy away from launching or detonating nuclear weapons in space. No country has detonated a nuclear weapon in orbit since the 1960s, and it remains unclear how many, if any, nuclear weapons are currently stationed in space undetected.

But the possibility became harder to dismiss in 2024, when U.S. officials said they had evidence that Russia was developing a nuclear anti-satellite weapon — a claim Moscow has denied. The alleged spacecraft, based on media reports, is the Russian military radar satellite Kosmos-2553, which in 2022 launched into a radiation-heavy orbit that most other communication spacecraft avoid, Mallory Stewart of the U.S. State Department said in a 2024 interview. .

While Russia said the mission was meant for accelerated testing of how onboard electronics handle radiation, U.S. officials said the radiation level at that altitude was not high enough for such testing. The satellite was later observed tumbling and making erratic movements. This behavior raised suspicions that the spacecraft could be maneuvering toward a target satellite to detonate as a nuclear weapon, given Russia's "demonstrated willingness to target US and allied on-orbit objects," U.S. Space Command representatives said, according to a report from The Guardian.

The stakes are higher now than they were decades ago. All three experts interviewed for this story agreed that a space-based nuclear detonation today would be catastrophic — largely because of Earth's cluttered orbit. In 1962, 24 satellites, operated by two countries (the U.S. and the Soviet Union), were in orbit. According to a tracker maintained by astronomer Jonathan McDowell, more than 48,000 objects launched by more than 190 countries are tracked in space today; together, they support the communications, navigation, weather forecasting, Earth observation and military systems the world now runs on.

Even satellites that aren't in the blast radius could be damaged by a nuclear explosion in orbit. Modern satellites are built with off-the-shelf, low-cost electronics to keep pace with commercial demand, and they "are probably not hardened against the kinds of radiation you would get from a nuclear detonation of space," Weeden said. "I think that is the biggest concern."

A federal government study had found that a single high-altitude nuclear blast could raise radiation in low Earth orbit enough to disable nearly all unhardened satellites within weeks to months, with direct financial damages approaching $500 billion and the total economic impact potentially topping $3 trillion. The potential losses have only grown as the number of satellites has exploded and the world's dependence on them has increased. At the same time, declining launch costs have lowered the barrier to entry for spaceflight, opening orbit to nonstate actors without sizable satellite fleets of their own. That dynamic makes it more attractive for such actors to exploit major powers' deep economic and military reliance on space, Roberts said.

"It's most attractive for a rogue state like North Korea," he added. "It's not attractive for a spacefaring state like Russia. Doesn't mean they won't do it; it's just that there's enormous amounts of cons to that type of attack."

Ultimately, whether space-based nuclear weapon detection methods like those proposed by the MIT study wind up being useful is a policy question, Weeden said.

Implementing such a detection system "would raise a whole bunch of new discussions about on-orbit inspections and what are the international norms around that," Weeden said.

When archaeologists with the National Museum of Denmark excavated a burial mound called Guldhøj (Gold Hill) in southern Jutland in 1891, they were surprised to find a well-preserved wooden folding chair similar to those known from ancient Egypt and Greece. But the Guldhøj folding chair was made in Denmark around 3,400 years ago and is the only completely preserved chair from the Bronze Age in Europe, according to the National Museum of Denmark.

The chair was discovered in the grave of a chieftain, who was buried in a hollowed-out oak tree trunk and wrapped in a cowhide. The man had been dressed in a wool cloak secured with a bronze brooch, two wool hats, woolen mittens and leather shoes. Among the offerings his loved ones left in the grave were a bronze ax and a bronze dagger, along with two ornate wooden bowls and a wooden box. But the folding chair was an unusual addition to the grave and was likely a marker of the man's extremely high status.

The frame of the Guldhøj folding chair was crafted from ash wood, while the seat was made from otter skin, only a fragment of which was preserved over the millennia. Patterns incised into the top of the wooden frame were inlaid with a black, tar-like substance to create a band of geometric decoration.

In a 1999 study led by archaeologist Kirsten Prangsgaard, researchers who examined the chair determined that it was made from two frames of wood, each about 13 inches (33 centimeters) tall. When the frames were put together at a 45-degree angle, the low chair or stool would have been around 9.5 inches (24 cm) off the ground. Originally, the chair frame was likely held together with bronze nails, which may have been removed before the seat was placed in the grave, according to the researchers.

Folding chairs may seem simple, but they were important pieces of furniture that signified the seated person was of high rank, and they were likely used in rituals or ceremonies, according to the National Museum of Denmark.

Archaeologists have found ancient folding chairs in this style in Bronze Age Egypt and Greece, where weather conditions are better for preserving organic material such as wood. The Guldhøj folding chair is not unique in Nordic countries; pieces of chairs have been found in other chieftain graves in Denmark and northern Germany, and a rare metal folding chair was even found in an early medieval woman's grave in Germany. However, it is the only completely preserved wooden folding chair from Bronze Age Europe, Prangsgaard and colleagues noted in the study. "The folding chairs thus seem to belong to the warrior graves of the Early Bronze Age," they wrote.

The similarity of the Guldhøj chair, which was made in Denmark, to chairs found in far-flung civilizations means that Bronze Age people were exchanging ideas through trade and gift giving, the researchers wrote. The chairs show a clear artistic connection between Bronze Age Nordic and Mediterranean groups. Another connection is the four-spoked wheel on the famous Sun Chariot from Trundholm, which mimics designs seen in the Aegean region.

Both the unusual folding chair and the wooden bowls buried with the Bronze Age chieftain in the Guldhøj mound "can only be described as rare objects of high prestige," according to the National Museum of Denmark.

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

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