"In September 2024, U.S. scientists made key advances towards building a nuclear clock — a step beyond an atomic clock," according to ScienceAlert: In contrast to the atomic clock, the transition measured by this new device happens in the nucleus, or core, of the atom (hence the name), which gives it an even higher frequency. Thorium-229, the atom used for this study, offers a nuclear transition that can be excited by ultraviolet light. The team working on the nuclear clock overcame the technological challenge of building a frequency comb that works at the relatively high frequency range of ultraviolet light. This was a big step forward because nuclear transitions usually only become visible at much higher frequencies — like those of gamma radiation. But we are not able to accurately measure transitions in the gamma range yet.

The thorium atom transition has a frequency roughly one million times higher than the caesium atom's. This means that, although it has been measured with a lower accuracy than the current state-of-the-art strontium clock, it promises a new generation of clocks with much more precise definitions of the second. Measuring time to the nineteenth decimal place, as nuclear clocks could do, would allow scientists to study very fast processes... [G]eneral relativity is used to study high speed processes that could lead to overlaps with quantum mechanics. A nuclear clock will give us the technology necessary for proving these theories. [The clocks "will enable the study of the union of general relativity and quantum mechanics once they become sensitive to the finite wavefunction of quantum objects oscillating in curved space-time," according to the abstract of the researchers' paper.]

On a technological level, precise positioning systems such as GPS are based on complex calculations that require fine measurements of the time required by a signal to jump from one device to a satellite and onto another device. A better definition of the second will translate to much more accurate GPS. Time might be up for the caesium second, but a whole new world awaits beyond it.
As the researchers explain their paper's abstract,

60-year-old Chinese virologist Shi Zhengli led the Wuhan Institute of Virology's group studying bat coronaviruses (prompting Science magazine to call her "Bat Woman"). In June of 2020 Scientific American described Zhengli as "distressed because stories from the Internet and major media have repeated a tenuous suggestion that SARS-CoV-2 accidentally leaked from her lab — despite the fact that its genetic sequence does not match any her lab had previously studied."

More than four years later, Nature writes Friday that Zhengli "reported that none of the viruses stored in her freezers are the most recent ancestors of the virus SARS-CoV-2," presenting data at a conference in Japan "on dozens of new coronaviruses collected from bats in southern China." Shi has consistently said that SARS-CoV-2 was never seen or studied in her lab. But some commentators have continued to ask whether one of the many bat coronaviruses her team collected in southern China over decades was closely related to it. Shi promised to sequence the genomes of the coronaviruses and release the data. The latest analysis, which has not been peer reviewed, includes data from the whole genomes of 56 new betacoronaviruses, the broad group to which SARS-CoV-2 belongs, as well as some partial sequences. All the viruses were collected between 2004 and 2021.

"We didn't find any new sequences which are more closely related to SARS-CoV-1 and SARS-CoV-2," said Shi, in a pre-recorded presentation at the conference... The results support her assertion that the WIV lab did not have any bat-derived sequences from viruses that were more closely related to SARS-CoV-2 than were any already described in scientific papers, says Jonathan Pekar, an evolutionary biologist at the University of Edinburgh, UK. "This just validates what she was saying: that she did not have anything extremely closely related, as we've seen in the years since," he says.
"Earlier this year, Shi moved from the WIV to the Guangzhou Laboratory, a newly established national research institute for infectious diseases."

Space.com calls it "the once-in-a-lifetime reignition of a long-dead star in an explosion powerful enough to briefly match the brilliance of Polaris, the North Star." In March CNN promised this once-every-79-years event would happen "anytime between now and September."

But it didn't...

Space.com has a spectacular animation showing what this "recurring nova" was supposed to look like (described by CNN as a "sudden, brief explosion" from a collapsed/"white dwarf" star). "The highly-anticipated 'guest star' of the night sky has yet to deliver its grand performance," adds Space.com, "but we have an update." For a quick recap... T Coronae Borealis — often called T Cor Bor or T CrB — is home to a white dwarf, a dense, burnt-out star siphoning material from its companion star, which is a massive red giant close to the end of its life. This material spirals into an accretion disk around the white dwarf, where it slowly coats the star's surface. Every 80 years or so, the white dwarf manages to accumulate enough mass to trigger a nuclear explosion, sparking an outburst that boosts its typically dim magnitude of 10 to a bright 2.0 — that should look like a "new star" in the night sky to us...

[T]he elusive system continues to show signs that an outburst is still imminent. So, what gives? "We know it has to happen," astrophysicist Elizabeth Hays, who is watching T CrB every day using NASA's Fermi gamma-ray space telescope, told Space.com in a recent interview. "We just can't pin it down to the month."

The unpredictability stems partly from limited historical records of T CrB's outbursts. Only two such eruptions have been definitively observed in recent history: on May 12, 1866, when a star's outburst briefly outshined all the stars in its constellation, reaching magnitude 2.0, and again on February 9, 1946, when it peaked at magnitude 3.0. These events appear to follow the star's roughly 80-year cycle, suggesting that the next outburst may not occur until 2026. However, in February 2015, the system brightened in a manner reminiscent of its behavior in 1938, eight years before its 1946 eruption. This rise in brightness suggested T CrB's outburst was accelerated to 2023. The system also endured a "unique and mysterious" dimming about a year before its 1946 outburst, and a similar dip started in March last year, prompting astronomers to adjust their predictions to 2024.

Yet, the cause of this pre-eruption dip in brightness remains unclear, making it only a coincidental predictor. "We got really excited when it looked like it was doing similar things," said Hays. "Now we're learning, 'Oh, there's another piece we can't see.'" Moreover, the rate at which the red giant's material is being drawn toward the white dwarf may fluctuate over the years, making it trickier to put a date on the calendar for the outburst, Edward Sion, a professor of astronomy and astrophysics at Villanova University in Pennsylvania, told Space.com... "There's a lot of uncertainty about the actual average accretion rate," said Sion.
The article points out that last time there was an eruption, "there were no X-ray or gamma-ray telescopes in space, so there is no data from wavelengths other than optical to shed light on what happened before the outburst." But this time astrophysicist Hays says "We're getting the best dataset we've ever had on what does nova look like before it goes off".

Space.com says "this wealth of data will allow them to better predict future outbursts, and will eventually benefit models of how stars work."

Thanks to long-time Slashdot reader Okian Warrior for sharing the article.

"SpaceX has launched 20 of its Starlink satellites up into Earth's orbit, enabling direct-to-cellphone connectivity for subscribers anywhere on the planet," reports the tech blog New Atlas. That completes the constellation's first orbital shell, following a launch of an initial batch of six satellites for testing back in January. The satellites were launched with a Falcon 9 rocket from California's Vandenberg Space Force Base on December 5 at 10 PM EST; they were then deployed in low Earth orbit. SpaceX founder Elon Musk noted on X that the effort will "enable unmodified cellphones to have internet connectivity in remote areas." He added a caveat for the first orbital shell — "Bandwidth per beam is only ~10 Mb, but future constellations will be much more capable...."

The big deal with this new venture is that unlike previous attempts at providing satellite-to-phone service, you don't need a special handset or even a specific app to get access anywhere in the world. Starlink uses standard LTE/4G protocols that most phones are compatible with, partners with mobile operators like T-Mobile in the U.S. and Rogers in Canada, and has devised a system to make its service work seamlessly with your phone when it's connecting to satellites 340 miles (540 km) above the Earth's surface. The SpaceX division noted it's also worked out latency constraints, ideal altitudes and elevation angles for its satellites, along with several other parameters, to achieve reliable connectivity. Each satellite has an LTE modem on board, and these satellites plug into the massive constellation of 6,799 existing Starlink spacecraft, according to Space.com.

Connecting to that larger constellation happens via laser backhaul, where laser-based optical communication systems transmit data between satellites. This method leverages the advantages of lasers over traditional radio frequency communications, enabling data rates up to 100 times faster, increased bandwidth, and improved security.
The direct-to-cell program was approved last month, the article points out — but it's ready to ramp up. "You'll currently get only text service through the end of 2024; voice and data will become available sometime next year, as will support for IoT devices (such as smart home gadgets). The company hasn't said how much its service will cost. " (They also note there's already competing services from Lynk, "which has satellites in orbit and launched in the island nation of Palau back in 2023, and AST SpaceMobile, which also has commercial satellites in orbit and contracts with the U.S. government, Europe, and Japan.")

Elon Musk's announcement on X.com prompted this interesting exchange:

X.com User: You've stated that purchasing Starlink goes toward funding the journey to Mars, yes?

Elon Musk: Yes.

The use of lead in gasoline "might have harmed the mental health of a generation," reports USA Today. Gen X bears an extra burden of conditions such as depression, anxiety, ADHD and neurotic behavior because of the leaded gasoline they were exposed to as children, according to a study published Wednesday in the peer-reviewed Journal of Child Psychology and Psychiatry. Leaded gas was banned in the United States in 1996, but the study said years of exposure during development made them particularly vulnerable.

Lead gas peaked from the mid-1960s through the mid-1970s, and children born during that era would later develop some of the highest rates of mental health symptoms, the study said. The study also linked leaded gas to "disadvantageous" traits, such as struggling to concentrate, stay on task or organizing thoughts. "I tend to think of Generation X as 'generation lead,'" said Aaron Reuben, a study co-author and assistant professor of clinical neuropsychology at the University of Virginia. "We know they were exposed to it more and we're estimating they have gone on to have higher rates of internalizing conditions like anxiety, depression and symptoms of attention deficit hyperactivity disorder...."

Researchers linked the lead exposure to an estimated 151 million "excess mental disorders" in the United States over the 75-year period. The estimates should be "considered a floor" because it relies mainly on gas and not exposure from lead in paint and pipes, Reuben said... Those born between 1966 and 1986 generally had higher mental illness levels linked to lead exposure with the rates peaking for those born between 1966 and 1970, the study said. Those rates coincided with the peak use of lead in gas from the mid-1960s through the mid-1970s... The study said the peak lead use coincided with increased demand for psychiatric care and higher rates of juvenile delinquency.
Today there's routine blood screenings for high levels of lead, study co-author Reuben says. But in the 1960s, 1970s, and 1980s, "folks were walking around with an average blood lead value that today would trigger clinical follow-up."

"Are Primordial Black Holes real...?" asks Universe Today. "If they do exist, a "new paper suggests they may be hiding in places so unlikely that nobody ever thought to look there..." — in planets, in asteroids, and here on earth. Physicists hypothesize that Primordial Black Holes (PBHs) formed in the early Universe from extremely dense pockets of sub-atomic matter that collapsed directly into black holes. They could form part or all of what we call dark matter. However, they remain hypothetical because none have been observed... The authors claim that evidence for PBHs could be found in objects as large as hollowed out planetoids or asteroids and objects as small as rocks here on Earth. "Small primordial black holes could be captured by rocky planets or asteroids, consume their liquid cores from inside and leave hollow structures," the authors write. "Alternatively, a fast black hole can leave a narrow tunnel in a solid object while passing through it."

"We could look for such micro-tunnels here on Earth in very old rocks," the authors claim, explaining that the search wouldn't involve specialized, expensive equipment... "The chances of finding these signatures are small, but searching for them would not require much resources and the potential payoff, the first evidence of a primordial black hole, would be immense," said Dejan Stojkovic [the paper's co-author from the State University of New York]. "We have to think outside of the box because what has been done to find primordial black holes previously hasn't worked...." Cosmology is kind of at a standstill while we wrestle with the idea of dark matter. Could PBHs be dark matter? Could they behave like the authors suggest, and be detected in this manner?

"The smartest people on the planet have been working on these problems for 80 years and have not solved them yet," Stojkovic said. "We don't need a straightforward extension of the existing models. We probably need a completely new framework altogether."

America's next president "announced Wednesday he has selected Jared Isaacman, a billionaire businessman and space enthusiast who twice flew to orbit with SpaceX, to become the next NASA administrator," reports Ars Technica: In a post on X, Isaacman said he was "honored" to receive Trump's nomination. "Having been fortunate to see our amazing planet from space, I am passionate about America leading the most incredible adventure in human history," Isaacman wrote. "On my last mission to space, my crew and I traveled farther from Earth than anyone in over half a century. I can confidently say this second space age has only just begun...."

"Jared Isaacman will be an outstanding NASA Administrator and leader of the NASA family," said Jim Bridenstine, who led NASA as administrator during Trump's first term in the White House. "Jared's vision for pushing boundaries, paired with his proven track record of success in private industry, positions him as an ideal candidate to lead NASA into a bold new era of exploration and discovery. I urge the Senate to swiftly confirm him." Lori Garver, NASA's deputy administrator during the Obama administration, wrote on X that Isaacman's nomination was "terrific news," adding that "he has the opportunity to build on NASA's amazing accomplishments to pave our way to an even brighter future."

Isaacman, 41, is the founder and CEO of Shift4, a mobile payment processing platform, and co-founded Draken International, which owns a fleet of retired fighter jets to pose as adversaries for military air combat training... Isaacman, an evangelist for the commercial space industry, has criticized some of NASA's decisions on the Artemis program. In several posts on X, he questioned the agency's decision to fund two redundant lunar landers, while not planning for any backup to the Space Launch System (SLS) rocket, which costs $2.2 billion per copy, not including expenses for ground infrastructure or the Orion spacecraft itself. One of those casualties might be the SLS rocket. The program is managed by NASA, with suppliers spread across the United States and prime contractors working under cost-plus arrangements with the space agency, meaning the government is on the hook to pay for any delays or cost overruns.
If confirmed he'll be the 4th NASA administrator who's actually flown in space, according to the article.

And according to Wikipedia, Isaacman was the commander of Inspiration4, a private spaceflight using SpaceX's Crew Dragon Resilience that launched in 2021. The crew returned to Earth on September 18, 2021, after orbiting at 585 km (364 mi) in altitude. The mission was part of a fundraiser for St. Jude Children's Research Hospital, to which Isaacman pledged to donate $100 million.
Thanks to Slashdot reader FallOutBoyTonto for sharing the news.

Nature: Millions of research articles are absent from major digital archives. This worrying finding, which Nature reported on earlier this year, was laid bare in a study by Martin Eve, who studies technology and publishing at Birkbeck, University of London. Eve sampled more than seven million articles with unique digital object identifiers (DOIs), a string of characters used to identify and link to specific publications, such as scholarly articles and official reports. Of these, he found that more than two million were 'missing' from archives -- that is, they were not preserved in major archives that ensure literature can be found in the future.

Eve, who is also a research developer at Crossref, an organization that registers DOIs, carried out the study in an effort to better understand a problem librarians and archivists already knew about -- that although researchers are generating knowledge at an unprecedented rate, it is not necessarily being stored safely for the future. One contributing factor is that not all journals or scholarly societies survive in perpetuity. For example, a 2021 study found that a lack of comprehensive and open archiving meant that 174 open-access journals, covering all major research topics and geographical regions, vanished from the web in the first two decades of this millennium.

A lack of long-term archiving particularly affects institutions in low- and middle-income countries, less-affluent institutions in rich countries and smaller, under-resourced journals worldwide. Yet it's not clear whether researchers, institutions and governments have fully taken the problem on board. [...] At the heart of the problem is a lack of money, infrastructure and expertise to archive digital resources. [...] For institutions that can afford it, one solution is to pay a preservation archive to safeguard content. Examples include Portico, based in New York City, and CLOCKSS, based in Stanford, California, both of which count a raft of publishers and libraries as customers.

India has struck a landmark $715 million deal with 30 global academic publishers to provide nationwide free access to nearly 13,000 research journals. The "One Nation One Subscription" initiative, launching January 2025, will benefit an estimated 18 million students and researchers. The agreement, which surpasses similar arrangements in Germany and the UK, marks a significant shift in India's academic publishing landscape, despite the country's position as the world's third-largest producer of research papers. Science magazine: India's is expected to encompass some 6300 government-funded institutions, which produce almost half the country's research papers. Currently, only about 2300 of these institutions have subscriptions to 8000 journals. Under the new arrangement, "universities that aren't so well funded, and can't afford many journals, will gain," said Aniket Sule of the Homi Bhabha Centre for Science Education. Specialist institutes that only subscribe to journals relevant to their field will benefit from accessing work outside their silos, he added. Colleges that want to subscribe to journals not included under this initiative can use their own funds to do so.

Some part of the $715 million will cover the fees some journals charge to publish papers open access, making them immediately free to read by anyone worldwide when published, Madalli told Science. Details of that component have not been worked out yet, but the amount will be calculated based on the country's current spending on these fees, known as article-processing charges (APCs), which are paid by authors or their institutions, Madalli says.

"If NASA establishes a permanent presence on the moon, its astronauts' homes could be made of a new 3D-printable, waterless concrete," writes MIT Technology Review. "Someday, so might yours.

"By accelerating the curing process for more rapid construction, this sulfur-based compound could become just as applicable on our home terrain as it is on lunar soil..." Building a home base on the moon will demand a steep supply of moon-based infrastructure: launch pads, shelter, and radiation blockers. But shipping Earth-based concrete to the lunar surface bears a hefty price tag. Sending just 1 kilogram (2.2 pounds) of material to the moon costs roughly $1.2 million, says Ali Kazemian, a robotic construction researcher at Louisiana State University (LSU). Instead, NASA hopes to create new materials from lunar soil and eventually adapt the same techniques for building on Mars.

Traditional concrete requires large amounts of water, a commodity that will be in short supply on the moon and critically important for life support or scientific research, according to the American Society of Civil Engineers. While prior NASA projects have tested compounds that could be used to make "lunarcrete," they're still working to craft the right waterless material.

So LSU researchers are refining the formula, developing a new cement based on sulfur, which they heat until it's molten to bind material without the need for water. In recent work, the team mixed their waterless cement with simulated lunar and Martian soil to create a 3D-printable concrete, which they used to assemble walls and beams. "We need automated construction, and NASA thinks 3D printing is one of the few viable technologies for building lunar infrastructure," says Kazemian.

Beyond circumventing the need for water, the cement can handle wider temperature extremes and cures faster than traditional methods. The group used a pre-made powder for their experiments, but on the moon and Mars, astronauts might extract sulfur from surface soil.
Kazemian and his colleagues recently transferred the technology to NASA's Marshall Space Flight Center for further testing...

An anonymous reader shared this report from Reuters: The rapid increase in satellites and space junk will make low Earth orbit unusable unless companies and countries cooperate and share the data needed to manage that most accessible region of space, experts and industry insiders said. A United Nations panel on space traffic coordination in late October determined that urgent action was necessary and called for a comprehensive shared database of orbital objects as well as an international framework to track and manage them. More than 14,000 satellites including some 3,500 inactive surround the globe in low Earth orbit, showed data from U.S.-based Slingshot Aerospace. Alongside those are about 120 million pieces of debris from launches, collisions and wear-and-tear of which only a few thousand are large enough to track... [T]here is no centralised system that all space-faring nations can leverage and even persuading them to use such a system has many obstacles. Whereas some countries are willing to share data, others fear compromising security, particularly as satellites are often dual-use and include defence purposes. Moreover, enterprises are keen to guard commercial secrets.

In the meantime, the mess multiplies. A Chinese rocket stage exploded in August, adding thousands of fragments of debris to low Earth orbit. In June, a defunct Russian satellite exploded, scattering thousands of shards which forced astronauts on the International Space Station to take shelter for an hour... Projections point to tens of thousands more satellites entering orbit in the coming years. The potential financial risk of collisions is likely to be $556 million over five years, based on a modelled scenario with a 3.13% annual collision probability and $111 million in yearly damages, said Montreal-based NorthStar Earth & Space...

[Aarti Holla-Maini, director of the U.N . Office for Outer Space Affairs], said the October panel aimed to bring together public- and private-sector experts to outline steps needed to start work on coordination. It will present its findings at a committee meeting next year. Global cooperation is essential to developing enforceable rules akin to those used by the International Civil Aviation Organization for air traffic, industry experts told Reuters. Such effort would involve the use of existing tools, such as databases, telescopes, radars and other sensors to track objects while improving coverage, early detection and data precision. Yet geopolitical tension and reluctance to share data with nations deemed unfriendly as well as commercial concerns over protecting proprietary information and competitive advantages remain significant barriers. That leaves operators of orbital equipment relying on informal or semi-formal methods of avoiding collisions, such as drawing on data from the U.S. Space Force or groups like the Space Data Association. However, this can involve issues such as accountability and inconsistent data standards.

"The top challenges are speed — as consensus-building takes time — and trust," Holla-Maini said. "Some countries simply can't communicate with others, but the U.N. can facilitate this process. Speed is our biggest enemy, but there's no alternative. It must be done."
Data from Slingshot Aerospace shows a 17% rise in close approaches per satellite over the past year, according to the article. (It adds that SpaceX data "showed Starlink satellites performed nearly 50,000 collision-avoidance manoeuvres in the first half of 2024, about double the previous six months...)

The European Space Agency, which has fewer spacecraft than SpaceX, said in 2021 its manoeuvres have increased to three or four times per craft versus a historical average of one."

Slashdot reader sciencehabit writes: Most orange cats are boys, a quirk of feline genetics that also explains why almost all calicos and tortoiseshells are girls. Scientists curious about those sex differences—or perhaps just cat lovers—have spent more than 60 years unsuccessfully seeking the gene that causes orange fur and the striking patchwork of colors in calicos and tortoiseshells. Now, two teams have independently found the long-awaited mutation and discovered a protein that influences hair color in a way never seen before in any animal... Using skin samples collected from various cats, the researchers were able to hone in a mutation on the X chromosome that impacts how much of a protein a gene called Arhgap36 produces. Increasing the amount of the Arhgap36 in pigment producing cells called melanocytes activates a molecular pathway that produces a light red pigment.
"Scanning a database of 188 cat genomes, Barsh's team found every single orange, calico, and tortoiseshell cat had the exact same mutation," writes Science magazine. "The group reports the discovery this month on the preprint server bioRxiv. A separate study, also posted to bioRxiv this month, confirms these findings... They also found that skin from calico cats had more Arghap36 RNA in orange regions than in brown or black regions." Arhgap36's inactivation pattern in calicos and tortoiseshells is typical of a gene on the X chromosome, says Carolyn Brown [a University of British Columbia geneticist who was not involved in either study], but it's unusual that a deletion mutation would make a gene more active, not less. "There is probably something special about cats." Experts are thrilled by the two studies. "It's a long-awaited gene," says Leslie Lyons, a feline geneticist at the University of Missouri. The discovery of a new molecular pathway for hair color was unexpected, she says, but she's not surprised how complex the interactions seem to be. "No gene ever stands by itself."

Lyons would like to know where and when the mutation first appeared: There is some evidence, she says, that certain mummified Egyptian cats were orange. Research into cat color has revealed all kinds of phenomena, she says, including how the environment influences gene expression. "Everything you need to know about genetics you can learn from your cat."

"Spacecraft, satellites, and space-based systems all face cybersecurity threats that are becoming increasingly sophisticated and dangerous," reports CNBC.

"With interconnected technologies controlling everything from navigation to anti-ballistic missiles, a security breach could have catastrophic consequences." Critical space infrastructure is susceptible to threats across three key segments: in space, on the ground segment and within the communication links between the two. A break in one can be a cascading failure for all, said Wayne Lonstein, co-founder and CEO at VFT Solutions, and co-author of Cyber-Human Systems, Space Technologies, and Threats. "In many ways, the threats to critical infrastructure on Earth can cause vulnerabilities in space," Lonstein said. "Internet, power, spoofing and so many other vectors that can cause havoc in space," he added. The integration of artificial intelligence into space projects has heightened the risk of sophisticated cyber attacks orchestrated by state actors and individual hackers. AI integration into space exploration allows more decision-making with less human oversight.

For example, NASA is using AI to target scientific specimens for planetary rovers. However, reduced human oversight could make these missions more prone to unexplained and potentially calamitous cyberattacks, said Sylvester Kaczmarek, chief technology officer at OrbiSky Systems, which specializes in the integration of AI, robotics, cybersecurity, and edge computing in aerospace applications. Data poisoning, where attackers feed corrupted data to AI models, is one example of what could go wrong, Kaczmarek said. Another threat, he said, is model inversion, where adversaries reverse-engineer AI models to extract sensitive information, potentially compromising mission integrity. If compromised, AI systems could be used to interfere with or take control of strategically important national space missions...

The U.S. government is tightening up the integrity and security of AI systems in space. The 2023 Cyberspace Solarium Commission report stressed the importance of designating outer space as a critical infrastructure sector, urging enhanced cybersecurity protocols for satellite operators... The rivalry between the U.S. and China includes the new battleground of space. As both nations ramp up their space ambitions and militarized capabilities beyond Earth's atmosphere, the threat of cyberattacks targeting critical orbital assets has become an increasingly pressing concern... Space-based systems increasingly support critical infrastructure back on Earth, and any cyberattacks on these systems could undermine national security and economic interests.

"Polar oceans constitute emission hotspots during the summer," according to a new paper published in the peer-reviewed scientific journal Science Advances. "And including those sea-to-air fluxes in an atmospheric chemistry-climate model "results in a net radiative effect that has far-reaching implications."

The research was led by a team of scientists from Spain's Institute of Marine Sciences and the Blas Cabrera Institute of Physical Chemistry, according to an announcement from the UK's University of East Anglia: Researchers have quantified for the first time the global emissions of a sulfur gas produced by marine life, revealing it cools the climate more than previously thought, especially over the Southern Ocean. The study, published in the journal Science Advances, shows that the oceans not only capture and redistribute the sun's heat, but produce gases that make particles with immediate climatic effects, for example through the brightening of clouds that reflect this heat.

It broadens the climatic impact of marine sulfur because it adds a new compound, methanethiol, that had previously gone unnoticed. Researchers only detected the gas recently, because it used to be notoriously hard to measure and earlier work focussed on warmer oceans, whereas the polar oceans are the emission hotspots...

Their findings represent a major advance on one of the most groundbreaking theories proposed 40 years ago about the role of the ocean in regulating the Earth's climate. This suggested that microscopic plankton living on the surface of the seas produce sulfur in the form of a gas, dimethyl sulphide, that once in the atmosphere, oxidizes and forms small particles called aerosols. Aerosols reflect part of the solar radiation back into space and therefore reduce the heat retained by the Earth. Their cooling effect is magnified when they become involved in making clouds, with an effect opposite to, but of the same magnitude as, that of the well-known warming greenhouse gases, such as carbon dioxide or methane. The researchers argue that this new work improves our understanding of how the climate of the planet is regulated by adding a previously overlooked component and illustrates the crucial importance of sulfur aerosols. They also highlight the magnitude of the impact of human activity on the climate and that the planet will continue to warm if no action is taken.
The article includes this quote from one of the study's lead authors (Dr. Charel Wohl from the university's Centre for Ocean and Atmospheric Sciences). "Climate models have greatly overestimated the solar radiation actually reaching the Southern Ocean, largely because they are not capable of correctly simulating clouds. The work done here partially closes the longstanding knowledge gap between models and observations."

And the university's announcement argues that "With this discovery, scientists can now represent the climate more accurately in models that are used to make predictions of +1.5 degrees C or +2 degrees C warming, a huge contribution to policy making."

Thanks to long-time Slashdot reader schwit1 for sharing the news.

To explain the origins of dark market, a new model of the universe has been proposed by researchers, reports Phys.org.

"Their idea is that dark matter would be produced during a infinitesimally short inflationary phase when the size of the universe quickly expanded exponentially..." Although inflation is mostly accepted by cosmologists as part of the Big Bang picture based on some evidence (though there is meaningful dissent), the driver of inflation is still unknown... [T]o-date research has not considered the possibility that a significant [amount] of dark matter could be produced during the inflationary expansion and not be diluted away. In the paper's WIFI model — Warm Inflation via ultraviolet Freeze-In — dark matter is created through small and rare interactions with particles in a hot, energetic environment. It contains a new mechanism where this production occurs just before the Big Bang, during cosmic inflation, leading to dark matter being formed much earlier than in existing theories...

"The thing that's unique to our model is that dark matter is successfully produced during inflation," said Katherine Freese, Director of the Weinberg Institute of Theoretical Physics and the Texas Center for Cosmology and Astroparticle Physics at The University of Texas at Austin and lead author of the paper. "In most [other] models, anything that is created during inflation is then 'inflated away' by the exponential expansion of the universe, to the point where there is essentially nothing left." In this new mechanism, all the dark matter that we observe today could have been created during that brief, pre-Big Bang period of inflation. The quantum field driving inflation, the inflation, loses some of its energy to radiation, and this radiation, in turn, produces dark matter particles via the freeze-in mechanism....

The WIFI [Warm Inflation via ultraviolet Freeze-In] model cannot yet be confirmed by observations. But a key part of the scenario, warm inflation, will be tested over the next decade by the so-called cosmic microwave background experiments. Confirming warm inflation would be a significant step for the WIFI model's dark matter production scenario.
"What was before inflation? Physicists have no idea."

The Washington Post reports on tens of thousands of Americans "forced to pay for medication" to prevent the HIV infections, "despite federal requirements guaranteeing free access to treatment...according to multiple studies and interviews with medical professionals, activists and patients." Insurance companies are skirting rules compelling them to pay for pre-exposure prophylaxis treatment, known as PrEP, researchers and HIV advocacy organizations say — leaving patients to shell out hundreds of dollars each year for medication co-pays, doctor visits and screenings required to stay on drugs that reduce the risk of contracting HIV through sex by 99 percent.

Under the Affordable Care Act, commercial insurers must cover certain preventive health services. This is supposed to include at least one form of oral PrEP and related health services, such as regular testing for HIV and other sexually transmitted diseases, for people at increased risk of contracting HIV, according to 2021 guidance from the Biden administration. Responding to complaints that patients were still being charged, the Biden administration in October released new guidance instructing private insurers to cover all forms of PrEP without prior authorization, including new long-acting injections.

Nearly a third of a national sample of 325 health coverage plans on government insurance marketplaces did not include PrEP on their lists of covered preventive services, according to the AIDS Institute, a New York-based nonprofit. Between 20 and 30 percent of PrEP users with commercial insurance still had to pay for it despite the coverage mandate, with an average cost of $227 for 2022, according to the Centers for Disease Control and Prevention. Government regulators have been slow to crack down on insurer violations, activists say, creating a barrier to getting more at-risk Americans on the medication. The CDC estimates that only a third of the more than 1 million people who could benefit from PrEP have received a prescription, according to its most recent data.
The issue appears to be lax enforcement against insurers who break rules, a policy advocate told the newspaper. America's Centers for Medicare and Medicaid Services, which enforces regulations for preventive care, "said it takes enforcement seriously and recently found two insurance plans in violation of coverage requirements following consumer complaints."

And the Post spoke to an official at America's Labor Department, who said they were investigating a complaint against a large insurance company, but "said the agency does not have enough staff to conduct proactive investigations and lacks the authority to sue and penalize insurers that break the rules."

Major academic publishers including Elsevier and Springer Nature are grappling with a sophisticated new journal hijacking scam that precisely mimics their websites to deceive researchers.

The fraudulent operation, reported by Retraction Watch, has cloned at least 13 legitimate journals through fake domains, according to Crossref data. The scam, the publication reports, features high-quality website clones that replicate even cookie consent popups. The operation assigns its own DOI prefix to published papers and offers paper-writing and peer review services typical of paper mills.

A million and a half years ago, amid giant storks and the ancestors of antelopes, two extinct relatives of humans walked along the same muddy lakeshore in what is today northern Kenya, new research suggests. From a report: An excavation team uncovered four sets of footprints preserved in the mud at the Turkana Basin, a site that has led to important breakthroughs in understanding human evolution. The discovery, announced on Thursday in a paper in the journal Science, is direct evidence that different kinds of human relatives, with distinct anatomies and gaits, inhabited the same place at the same time, the paper's authors say. It also raises questions about the extent of the species' interactions with each other.

"They might have walked by one another," said Kevin Hatala, an evolutionary anthropologist at Chatham University in Pittsburgh who led the study. "They might have looked up in the distance and seen another member of a closely related species, occupying the same landscape." Based on skeletal remains found in the region, Dr. Hatala's team attributed the footprints to Paranthropus boisei and Homo erectus, two types of hominins, the group consisting of our human lineage and closely related species. Paranthropus boisei had smaller brains along with wide, flat faces and massive teeth and chewing muscles; Homo erectus more closely resembled modern human proportions and are thought to be our direct ancestors.

Longtime Slashdot reader AmiMoJo shares a report from Phys.org: Researchers from Imperial College London have discovered that a space-returned sample from asteroid Ryugu was rapidly colonized by terrestrial microorganisms, even under stringent contamination control measures. In the study, [...] researchers analyzed sample A0180, a tiny (1 x 0.8 mm) particle collected by the JAXA Hayabusa 2 mission from asteroid Ryugu.

Transported to Earth in a hermetically sealed chamber, the sample was opened in nitrogen in a class 10,000 clean room to prevent contamination. Individual particles were picked with sterilized tools and stored under nitrogen in airtight containers. Before analysis, the sample underwent Nano-X-ray computed tomography and was embedded in an epoxy resin block for scanning electron microscopy. Rods and filaments of organic matter, interpreted as filamentous microorganisms, were observed on the sample's surface. Variations in size and morphology of these structures resembled known terrestrial microbes. Observations showed that the abundance of these filaments changed over time, suggesting the growth and decline of a prokaryote population with a generation time of 5.2 days.

Population statistics indicate that the microorganisms originated from terrestrial contamination during the sample preparation stage rather than being indigenous to the asteroid. Results of the study determined that terrestrial biota had rapidly colonized the extraterrestrial material, even under strict contamination control. Researchers recommend enhanced contamination control procedures for future sample-return missions to prevent microbial colonization and ensure the integrity of extraterrestrial samples. Another factor in gathering contamination-free sampling is that everything used to collect extraterrestrial material originates on a planet awash in microbial life.

A University of Birmingham study reveals that PFAS and microplastics have a synergistic effect that significantly increases their toxicity. "The study's authors exposed water fleas to mixtures of the toxic substances and found they suffered more severe health effects, including lower birth rates, and developmental problems, such as delayed sexual maturity and stunted growth," reports The Guardian. From the report: The enhanced toxic effects raise alarm because PFAS and microplastics are researched and regulated in isolation from one one another, but humans are virtually always exposed to both. The research also showed those fleas previously exposed to chemical pollution were less able to withstand the new exposures. The findings "underscore the critical need to understand the impacts of chemical mixtures on wildlife and human health," wrote the study's authors, who are with the University of Birmingham in the United Kingdom.

Researchers compared a group of water fleas that had never been exposed to pollution with another group that had been exposed to pollution in the past. Water fleas have high sensitivity to chemicals so they are frequently used to study ecological toxicity. Both groups were exposed to bits of PET, a common microplastic, as well as PFOA and PFOS, two of the most common and dangerous PFAS compounds. The mixture reflected conditions common in lakes around the world.

The study's authors found the mixture to be more toxic than PFAS and microplastics in isolation. They attributed about 40% of the increased toxicity to a synergy among the substances that makes them even more dangerous. The authors theorized the synergy has to do with the interplay in the charges of microplastics and PFAS compounds. The remainder of the increased toxicity was attributed to simple addition of their toxic effects. Fleas exposed to the mixture showed a "markedly reduced number of offspring," the authors said. They were also smaller at maturation and showed delayed sexual growth.