Astronomers using the Vera C. Rubin Observatory have discovered a record-setting asteroid, known as 2025 MN45, nearly half a mile wide and spinning once every 1.88 minutes -- the fastest known rotation for an object of its size. "This is now the fastest-spinning asteroid that we know of, larger than 500 meters," said Sarah Greenstreet, University of Washington astronomer and lead author of the study. The findings have been published in the The Astrophysical Journal Letters. GeekWire reports: 2025 MN45 is one of more than 2,100 solar system objects that were detected during the observatory's commissioning phase. Over time, the LSST Camera tracked variations in the light reflected by those objects. Greenstreet and her colleagues analyzed those variations to determine the size, distance, composition and rate of rotation for 76 asteroids, all but one of which are in the main asteroid belt between the orbits of Mars and Jupiter. (The other asteroid is a near-Earth object.)

The team found 16 "super-fast rotators" spinning at rates ranging between 13 minutes and 2.2 hours per revolution -- plus three "ultra-fast rotators," including 2025 MN45, that make a full revolution in less than five minutes. Greenstreet said 2025 MN45 appears to consist of solid rock, as opposed to the "rubble pile" material that most asteroids are thought to be made of. "We also believe that it's likely a collisionary fragment of a much larger parent body that, early in the solar system's history, was heated enough that the material internal to it melted and differentiated," Greenstreet said. She and her colleagues suggest that the primordial collision blasted 2025 MN45 from the dense core of the parent body and sent it whirling into space.

OpenAI has unveiled ChatGPT Health, a sandboxed health-focused mode that lets users connect medical records and wellness apps for more personalized guidance. The company makes sure to note that ChatGPT Health is "not intended for diagnosis or treatment." The Verge reports: The company is encouraging users to connect their personal medical records and wellness apps, such as Apple Health, Peloton, MyFitnessPal,Weight Watchers, and Function, "to get more personalized, grounded responses to their questions." It suggests connecting medical records so that ChatGPT can analyze lab results, visit summaries, and clinical history; MyFitnessPal and Weight Watchers for food guidance; Apple Health for health and fitness data, including movement, sleep, and activity patterns"; and Function for insights into lab tests.

On the medical records front, OpenAI says it's partnered with b.well, which will provide back-end integration for users to upload their medical records, since the company works with about 2.2 million providers. For now, ChatGPT Health requires users to sign up for a waitlist to request access, as it's starting with a beta group of early users, but the product will roll out gradually to all users regardless of subscription tier. [...]

In a blog post, OpenAI wrote that based on its "de-identified analysis of conversations," more than 230 million people around the world already ask ChatGPT questions related to health and wellness each week. OpenAI also said that over the past two years, it's worked with more than 260 physicians to provide feedback on model outputs more than 600,000 times over 30 areas of focus, to help shape the product's responses. "ChatGPT can help you understand recent test results, prepare for appointments with your doctor, get advice on how to approach your diet and workout routine, or understand the tradeoffs of different insurance options based on your healthcare patterns," OpenAI claims in the blog post.

sinij shares a news release from the Utah Department of Commerce: The state of Utah, through the Utah Department of Commerce's Office of Artificial Intelligence Policy, today announced a first-of-its-kind partnership with Doctronic, the AI-native health platform, to give patients with chronic conditions a faster, automated way to renew medications. This agreement marks the first state-approved program in the country that allows an AI system to legally participate in medical decision-making for prescription renewals, an emerging model that could reshape access to care and ultimately improve care outcomes. Politico provides additional context in its reporting: In data shared with Utah regulators, Doctronic compared its AI system with human clinicians across 500 urgent care cases. The results showed the AI's treatment plan matched the physicians' 99.2 percent of the time, according to the company. "The AI is actually better than doctors at doing this," said Dr. Adam Oskowitz, Doctronic co-founder and an associate professor of surgery at the University of California San Francisco. "When you go see a doctor, it's not going to do all the checks that the AI is doing."

Oskowitz said the AI is designed to err on the side of safety, automatically escalating cases to a physician if there's any uncertainty. Human doctors will also review the first 250 prescriptions issued in each medication class to validate the AI's performance. Once that threshold is met, subsequent renewals in that class will be handled autonomously. The company has also secured a one-of-a-kind malpractice insurance policy covering an AI system, which means the system is insured and held to the same level of responsibility as a doctor would be.

Doctronic also runs a nationwide telehealth practice that directs patients to doctors after an AI consultation. In Utah, patients who use the system will visit a webpage that verifies they are physically in the state. Then the system will pull the patient's prescription history and offer a list of medications eligible for renewal. The AI walks the patient through the same clinical questions a physician would ask to determine whether a refill is appropriate. If the system clears the renewal, the prescription is sent directly to a pharmacy. The program is limited to 190 commonly prescribed medications. Some medications -- including pain management and ADHD drugs as well as injectables -- are excluded for safety reasons.

Jupiter's moon Europa is on the short list of places in our solar system seen as promising in the search for life beyond Earth, with a large subsurface ocean thought to be hidden under an outer shell of ice. But new research is raising questions about whether Europa in fact has what it takes for habitability. Reuters: The study assessed the potential on Europa's ocean bottom for tectonic and volcanic activity, which on Earth facilitate interactions between rock and seawater that generate essential nutrients and chemical energy for life. After modeling Europa's conditions, the researchers concluded that its rocky seafloor is likely mechanically too strong to allow such activity.

The researchers considered factors including Europa's size, the makeup of its rocky core and the gravitational forces exerted by Jupiter, the solar system's largest planet. Their evaluation that there probably is little to no active faulting at Europa's seafloor suggests this moon is barren of life.

"On Earth, tectonic activity such as fracturing and faulting exposes fresh rock to the environment where chemical reactions, principally involving water, generate chemicals such as methane that microbial life can use," said planetary scientist Paul Byrne of Washington University in St. Louis, lead author of the study published on Tuesday in the journal Nature Communications. "Without such activity, those reactions are harder to establish and sustain, making Europa's seafloor a challenging environment for life," Byrne added.

Scientists at Melbourne's Peter Doherty Institute for Infection and Immunity are working on a Crispr-based treatment -- delivered as a nasal spray or injection -- that could stop influenza infections by targeting the virus's RNA and disrupting its ability to replicate inside human cells.

The approach uses the Cas13 enzyme, a lesser-known cousin of the DNA-cutting Cas9, which can be engineered to seek out conserved regions of influenza's genetic code that are found in virtually all flu strains and are crucial to the virus's survival. The delivery mechanism would use lipid nanoparticles to ferry two molecular instructions to flu-infected cells in the respiratory tract: an mRNA that tells cells to produce Cas13 and a guide RNA that directs the enzyme to specific parts of the influenza virus's code.

Cas13 then cuts the viral RNA and effectively stops the infection at the genetic level, Sharon Lewin, the infectious diseases physician leading the project, told Wired. Early safety testing at Harvard's Wyss Institute used a "lung on a chip" model to examine whether human cells producing Cas13 could fight off flu strains including H1N1 and H3N2. The institute's founding director Donald Ingber says the studies showed no off-target effects.

"The ancient evolution of fish mouths could help solve a modern source of plastic pollution," writes ScienceAlert.

"Inspired by these natural filtration systems, scientists in Germany have invented a way to remove 99 percent of plastic particles from water. It's based on how some fish filter-feed to eat microscopic prey." The research team has already filed a patent in Germany, and in the future, they hope their creation will help curb a ubiquitous form of plastic pollution that many are unaware of. Every time a load of laundry is done, millions of microplastics are washed from the fibers of our clothes into local waterways. By some estimates, up to 90 percent of plastic in 'sewage sludge' comes from washing machines. This material is then often used in agriculture as soil or fertilizer, possibly exposing those who eat the resulting crops to these pollutants...

Unlike other plastic filtration systems on the market, this one reduces clogging by 85 percent.

An anonymous reader shared this report from the Independent: Candida auris, a type of invasive yeast that can cause deadly infections in people with weakened immune systems, has infected at least 7,000 people [in 2025] across 27 U.S. states, according to data from the Centers for Disease Control and Prevention. The fungus, which can spread easily in healthcare settings such as hospitals and nursing homes, is gaining virulence and spreading at an "alarming" rate, the CDC says. Some strains of the fungus are particularly troublesome — and even considered a superbug — because they're resistant to all types of antibiotics used to treat fungal infections, The Hill reports.

While healthy people may be able to fight off the infection on their own, the fungus can be deadly, especially in healthcare settings, where it can quickly spread amongst a vulnerable population. "If you get infected with this pathogen that's resistant to any treatment, there's no treatment we can give you to help combat it. You're all on your own," Melissa Nolan, an assistant professor of epidemiology and biostatistics at the University of South Carolina, told Nexstar...

A recent study found that Candida auris is gaining virulence and spreading rapidly, not just in the U.S., but also globally. Candida auris has already been found in at least 61 countries on six continents.
Some context from Newsweek: There are strategies available to combat Candida auris infection. While the superbug can develop ways to evade the immune response, vaccination and treatment strategies are possible, but researchers would like them to be strengthened. Four classes of antifungal drugs are currently available, with varying degrees of efficacy, and three new drugs are currently in trials or at newly approved stages

An AI chatbot to answer probate questions from Alaska residents "was supposed to be a three-month project," said Aubrie Souza, a consultant with the National Center for State Courts told NBC News. "We are now at well over a year and three months, but that's all because of the due diligence that was required to get it right." "With a project like this, we need to be 100% accurate, and that's really difficult with this technology," said Stacey Marz, the administrative director of the Alaska Court System and one of the Alaska Virtual Assistant (AVA) project's leaders... While many local government agencies are experimenting with AI tools for use cases ranging from helping residents apply for a driver's license to speeding up municipal employees' ability to process housing benefits, a recent Deloitte report found that less than 6% of local government practitioners were prioritizing AI as a tool to deliver services. The AVA experience demonstrates the barriers government agencies face in attempting to leverage AI for increased efficiency or better service, including concerns about reliability and trustworthiness in high-stakes contexts, along with questions about the role of human oversight given fast-changing AI systems. These limitations clash with today's rampant AI hype and could help explain larger discrepancies between booming AI investment and limited AI adoption.
The chatbot was developed with Tom Martin, a lawyer/law professor who designs legal AI tools, according to the article. But the project "had to contend with the serious issue of hallucinations, or instances in which AI systems confidently share false or exaggerated information." "We had trouble with hallucinations, regardless of the model, where the chatbot was not supposed to actually use anything outside of its knowledge base," Souza told NBC News. "For example, when we asked it, 'Where do I get legal help?' it would tell you, 'There's a law school in Alaska, and so look at the alumni network.' But there is no law school in Alaska." Martin has worked extensively to ensure the chatbot only references the relevant areas of the Alaska Court System's probate documents rather than conducting wider web searches.
The article concludes that "what was meant to be a quick, AI-powered leap forward in increasing access to justice has spiraled into a protracted, yearlong journey plagued by false starts and false answers." But the chatbot is now finally scheduled to be launched in late January. "It was just so very labor-intensive to do this," Marz said, despite "all the buzz about generative AI, and everybody saying this is going to revolutionize self-help and democratize access to the courts.

"It's quite a big challenge to actually pull that off."

"Starlink is beginning a significant reconfiguration of its satellite constellation focused on increasing space safety," announced Michael Nicolls, Starlink's vice president of engineering: "We are lowering all Starlink satellites orbiting at ~550 km to ~480 km (~4400 satellites) over the course of 2026. The shell lowering is being tightly coordinated with other operators, regulators, and USSPACECOM. Lowering the satellites results in condensing Starlink orbits, and will increase space safety in several ways... Starlink satellites have extremely high reliability, with only 2 dead satellites in its fleet of over 9000 operational satellites. Nevertheless, if a satellite does fail on orbit, we want it to deorbit as quickly as possible. These actions will further improve the safety of the constellation, particularly with difficult to control risks such as uncoordinated maneuvers and launches by other satellite operators.
But orbits are being lowered for another reason (besides quick de-orbiting), notes Space.com. Within the next four years the period of least solar activity is expected, a period which coincides with decreased atmospheric density, Nicolls added, "which means the ballistic decay time at any given altitude increases." [Bringing the satellites lower] will mean a >80% reduction in ballistic decay time in solar minimum, or 4+ years reduced to a few months," Nicolls wrote in his X post. "Correspondingly, the number of debris objects and planned satellite constellations is significantly lower below 500 km, reducing the aggregate likelihood of collision...." The downward migration in 2026 involves roughly half of SpaceX's Starlink megaconstellation, which currently consists of nearly 9,400 operational spacecraft (though that number is always growing).

A small section of the International Space Station that has experienced persistent leaks for years appears to have stopped venting atmosphere into space. ArsTechnica: The leaks were caused by microscopic structural cracks inside the small PrK module on the Russian segment of the space station, which lies between a Progress spacecraft airlock and the Zvezda module. The problem has been a long-running worry for Russian and US operators of the station, especially after the rate of leakage doubled in 2024. This prompted NASA officials to label the leak as a "high likelihood" and "high consequence" risk. However, recently two sources indicated that the leaks have stopped. And NASA has now confirmed this.

"Following additional inspections and sealing activities, the pressure in the transfer tunnel attached to the Zvezda Service Module of the International Space Station, known as the PrK, is holding steady in a stable configuration," a space agency spokesman, Josh Finch, told Ars. "NASA and Roscosmos continue to monitor and investigate the previously observed cracks for any future changes that may occur."

For the better part of half a decade, Russian cosmonauts have been searching for the small leaks like a proverbial needle in a haystack. They would periodically close the hatch leading to the PrK module and then, upon re-opening it, look for tiny accumulations of dust to indicate the leak sites. Then the Russian cosmonauts would apply a sealant known as Germetall-1 (which has now been patented) to the cracks. They would close the hatch again, monitor the pressure inside the PrK module, and begin the search anew for additional leaks. This process went on for years.

A new sweeping meta-analysis has found no reliable link between economic inequality and well-being or mental health, challenging a long-held assumption that has shaped public health policy discussions for decades. The study, led by Nicolas Sommet at the University of Lausanne and Annahita Ehsan at the University of British Columbia, synthesized 168 studies involving more than 11 million participants across most world regions. The researchers screened thousands of scientific papers and contacted hundreds of researchers to compile the dataset, extracting more than 100 study features from each paper and linking them to more than 500 World Bank indicators.

They also replicated their findings using Gallup World Poll data spanning 2005 to 2021, which surveyed more than two million respondents from more than 150 countries. People living in more economically unequal places did not, on average, report lower life satisfaction or happiness than those in more equal places. The average effect across studies was not statistically significant and was practically equivalent to zero. Studies that did find links between inequality and poorer mental health turned out to reflect publication bias, where small, noisy studies reporting larger effects were over-represented in the literature. The study adds: Further analyses showed that the near-zero averages conceal more-complex patterns. Greater income inequality was associated with lower well-being in high-inflation contexts and, surprisingly, higher well-being in low-inflation contexts. Greater inequality was also associated with poorer mental health in studies in which the average income was lower. We conclude that inequality is a catalyst that amplifies other determinants of well-being and mental health (such as inflation and poverty) but on its own is not a root cause of negative effects on well-being and mental health.

A Guardian investigation published Friday found that Google's AI Overviews -- the generative AI summaries that appear at the top of search results -- are serving up inaccurate health information that experts say puts people at risk of harm. The investigation, which came after health groups, charities and professionals raised concerns, uncovered several cases of misleading medical advice despite Google's claims that the feature is "helpful" and "reliable."

In one case described by experts as "really dangerous," Google advised people with pancreatic cancer to avoid high-fat foods, which is the exact opposite of what should be recommended and could jeopardize a patient's chances of tolerating chemotherapy or surgery. A search for liver blood test normal ranges produced masses of numbers without accounting for nationality, sex, ethnicity or age of patients, potentially leaving people with serious liver disease thinking they are healthy. The company also incorrectly listed a pap test as a test for vaginal cancer.

The Eve Appeal cancer charity noted that the AI summaries changed when running the exact same search, pulling from different sources each time. Mental health charity Mind said some summaries for conditions such as psychosis and eating disorders offered "very dangerous advice."

Google said the vast majority of its AI Overviews were factual and that many examples shared were "incomplete screenshots," adding that the accuracy rate was on par with featured snippets.

Every human body contains a small population of cells that are not genetically its own -- cells that crossed the placenta during pregnancy and that persist for decades after birth. These "microchimeric" cells, named after the lion-goat-serpent hybrid of Greek mythology, have been found in every organ studied so far, though they are exceedingly rare: one such cell exists for every 10,000 to 1 million of a person's own cells.

The cells were first noticed in the late 1800s when pathologist Georg Schmorl described placenta-like "giant cells" in the lungs of people who had died from eclampsia. In 1969, researchers detected Y-chromosome-containing white blood cells in people who would later give birth to boys. For more than two decades, scientists presumed these cells were temporary. That changed in 1993 when geneticist Diana Bianchi found Y-chromosome cells in women who had given birth to sons up to 27 years earlier.

The cells appear to have regenerative properties, transforming into blood vessels or skin cells to promote wound healing. They also challenge a central assumption of immunology -- that the immune system classifies cells as either "self" or "non-self" and rejects foreign material. Microchimeric cells should trigger rejection but do not. Higher-than-typical concentrations have been found in people with autoimmune conditions including diabetes, lupus, and scleroderma.

Mark Thomson, a professor of experimental particle physics at the University of Cambridge, takes over as CERN's director general this week, and one of his first major decisions during his five-year tenure will be shutting down the Large Hadron Collider for an extended upgrade. The shutdown starts in June to make way for the high-luminosity LHC -- a major overhaul involving powerful new superconducting magnets that will squeeze the collider's proton beams and increase their brightness. The upgrade will raise collisions tenfold and strengthen the detectors to better capture subtle signs of new physics. The machine won't restart until Thomson's term is nearly over.

Thomson is far from disconsolate about the downtime. "The machine is running brilliantly and we're recording huge amounts of data," he told The Guardian. "There's going to be plenty to analyse over the period." Beyond the upgrade, Thomson must shepherd CERN's plans for the Future Circular Collider, a proposed 91km machine more than three times the size of the current collider. Member states vote on the project in 2028; the first phase carries an estimated price tag of 15 billion Swiss francs (nearly $19 billion).

A UK-based company has successfully powered up a microwave-sized space factory in orbit, proving it can run a 1,000C furnace to manufacture ultra-pure semiconductor materials in microgravity. "The work that we're doing now is allowing us to create semiconductors up to 4,000 times purer in space than we can currently make here today," says Josh Western, CEO of Space Forge. "This sort of semiconductor would go on to be in the 5G tower in which you get your mobile phone signal, it's going to be in the car charger you plug an EV into, it's going to be in the latest planes." The BBC reports: Conditions in space are ideal for making semiconductors, which have the atoms they're made of arranged in a highly ordered 3D structure. When they are being manufactured in a weightless environment, those atoms line up absolutely perfectly. The vacuum of space also means that contaminants can't sneak in. The purer and more ordered a semiconductor is, the better it works.

[...] The company's mini-factory launched on a SpaceX rocket in the summer. Since then the team has been testing its systems from their mission control in Cardiff. Veronica Viera, the company's payload operations lead, shows us an image that the satellite beamed back from space. It's taken from the inside of the furnace, and shows plasma - gas heated to about 1,000C -- glowing brightly. [...]

The team is now planning to build a bigger space factory -- one that could make semiconductor material for 10,000 chips. They also need to test the technology to bring the material back to Earth. On a future mission, a heat shield named Pridwen after the legendary shield of King Arthur will be deployed to protect the spacecraft from the intense temperatures it will experience as it re-enters the Earth's atmosphere.