NASA is eyeing an April launch window for the upcoming Artemis II mission after it repaired a helium-flow issue on the Space Launch System upper stage rocket. "Work on the rocket and spacecraft will continue in the coming weeks as NASA prepares for rolling the rocket out to the launch pad again later this month ahead of a potential launch in April," NASA wrote in an update on Tuesday. Space.com reports: The repair work occurred inside the huge Vehicle Assembly Building (VAB) at NASA's Kennedy Space Center (KSC) in Florida. Artemis 2's SLS and Orion crew capsule have been in the VAB since Feb. 25, when they rolled back to the hangar from KSC's Launch Pad 39B. Just a few days earlier, the Artemis 2 stack successfully completed a wet dress rehearsal, a two-day-long practice run of the procedures leading up to launch.

In the wake of that test, however, NASA noticed an interruption in helium flow in the SLS' upper stage. That was a significant issue, because helium pressurizes the rocket's propellant tanks. Rollback was the only option, as the affected area in the upper stage was not accessible at the pad. The problem took a potential March launch out of play for Artemis 2, which will send four astronauts on a roughly 10-day flight around the moon. It will be the first crewed flight to the lunar neighborhood since Apollo 17 in 1972.

The next Artemis 2 launch window opens in April, with liftoff opportunities on April 1, April 3-6 and April 30. And those options apparently remain in play, thanks to recent work in the VAB. That work centered on a seal in an interface through which helium flows from ground equipment into the SLS upper stage. That seal was obstructing the interface, which is known as a quick disconnect.

alternative_right shares a report from ScienceAlert: According to a study of 38 adult human brains donated to science, superagers -- people who retain exceptional memory as they age -- have roughly twice as many immature neurons as their peers who age more typically. Moreover, people with Alzheimer's disease show a marked reduction in neurogenesis compared to a normal baseline. [...]

Led by researchers at the University of Illinois Chicago, the team set out to examine a variety of postmortem hippocampal tissue samples to see if they could identify markers of neurogenesis -- and if different groups had any notable differences. The brain samples were donated from five groups: eight healthy young adults, aged between 20 and 40; eight healthy agers, aged between 60 and 93; six superagers, aged between 86 and 100; six individuals with preclinical Alzheimer's pathology, aged between 80 and 94; and 10 individuals with an Alzheimer's diagnosis, aged between 70 and 93. The young healthy adult brain tissue was first analyzed to establish the neurogenesis pathways in the adult brain. Then, they analyzed 355,997 individual cell nuclei isolated from the hippocampus, searching for three different stages of cell development: Stem cells, which can develop into neurons; neuroblasts, which are stem cells in the process of that development; and immature neurons, on the verge of functionality. The results were striking.

"Superagers had twice the neurogenesis of the other healthy older adults," [says neuroscientist Orly Lazarov of the University of Illinois Chicago]. "Something in their brains enables them to maintain a superior memory. I believe hippocampal neurogenesis is the secret ingredient, and the data support that." That's an interesting result on its own, but the data from the individuals with preclinical Alzheimer's pathology and Alzheimer's diagnoses is where the real meat of the study sits. In the preclinical group, subtle molecular changes hinted that the system supporting new neuron growth was beginning to falter. In the Alzheimer's group, a clear drop in immature neurons was evident. A genetic analysis of the nuclei also showed that superager neural cells have increased gene activity linked to stronger synaptic connections, greater plasticity, and brain-derived neurotrophic factor, a critical protein for neural survival, growth, and maintenance. Taken together, these three things can be interpreted as resilience. The research has been published in the journal Nature.

"Saturn and some of its 274 moons are pretty weird," writes Smithsonian magazine: [Saturn moon] Titan has strangely few impact craters, Hyperion is tiny and misshapen, and Iapetus has a tilted orbit. What's more, planets tend to wobble along their rotational axes as they spin, like an off-kilter spinning top in the moments before it topples over. Formally called precession, scientists have long thought that Saturn's wobble rate should match Neptune's because they're probably gravitationally linked. However, data from NASA's Cassini spacecraft, which studied the ringed planet from 2004 to 2017, revealed that Saturn's precession rate is slightly speedier than Neptune's.

In 2022, some researchers suggested that the destruction of a hypothetical moon, called Chrysalis, around 160 million years ago may have knocked Saturn out of sync and formed the pieces that became the planet's rings. But this work implied that Chrysalis probably would've crashed into Titan, posing a major problem, study co-author Matija Äuk, an astronomer at the SETI Institute, tells New Scientist's Leah Crane. In that case, Chrysalis' debris couldn't have become the rings, he says.

So, Äuk and his colleagues used computer simulations to investigate what would happen if Chrysalis did smack into Titan. If that happened around 400 million years ago, they found, the crash would've wiped away Titan's craters and made its orbit more elliptical. The altered path may have slowly pushed the trajectories of other moons, which then scraped against one another and left chunks of ice and rock that now make up Saturn's rings. The timing seems to align with the rings' estimated age of roughly 100 million years. Additionally, one piece of kicked-up debris may have formed the weird moon Hyperion, which may have subsequently tilted the orbit of the moon Iapetus, according to the analysis. The scenario could also resolve Saturn's unexpected wobble, which is currently "a little bit too fast," Äuk tells Jacopo Prisco at CNN.
The study has been accepted for publication in the Planetary Science Journal, and is already available on the preprint server arXiv.

In a library in Florence, Italy, historian Ivan Malara noticed handwritten notes on a book printed in the 1500s — and recognized the handwriting as Galileo's. The finding "promises new insights into one of the most famous ideological transitions in the history of science," writes Science magazine — since the book Galileo annotated was a reprint of Ptolemy's second-century work arguing that the earth was the center of the universe. Galileo's notes, perhaps written around 1590, or roughly 2 decades before his groundbreaking telescope observations of the Moon and Jupiter, reveal someone who both revered and critically dissected Ptolemy's work. And they imply, Malara argues, that Galileo ultimately broke with Ptolemy's cosmos because his mastery of the traditional paradigm's reasoning convinced him that a heliocentric [sun-centered] system would better fulfill Ptolemy's own mathematical logic.

There's already 5,000 sensors embedded in Antarctica's ice to look for evidence of neutrinos, reports the Washington Post. But in November scientists drilled six new holes at least a mile and a half deep and installed cables with hundreds more light detectors — an upgrade to the massive 15-year-old IceCube Neutrino Observatory to detect the charged particles produced by lower-energy neutrinos interacting with matter: When they do, the neutrinos produce charged particles that travel through the ice at nearly the speed of light, creating a blue glow called Cherenkov radiation... "Within the first couple years, we should be making much better measurements," [said Erin O'Sullivan, an associate professor of physics at Uppsala University in Sweden and a spokesperson for the project.] "There's hope to expand the detector, by an order of magnitude in volume, so the important thing there is we're not just seeing a few neutrino point sources, but we're starting to be a true telescope. ... That's really the dream."
The scientists spent seven years planning the upgrade, according to the article. "To drill holes a mile and a half deep takes about 30 hours, and 18 more hours to return to the surface," the article points out. "Then, the race begins because almost immediately, the hole starts to shrink as the water refreezes." ("If it takes too much time, the principal investigator says, "the instruments don't fit in anymore!")

A start-up called Reflect Orbital "proposes to use large, mirrored satellites to redirect sunlight to Earth at night," reports the Washington Post, "with plans to bathe solar farms, industrial sites and even entire cities in light that could, if desired, reach the intensity of daylight...."

Slashdot noted their idea in 2022 — but Reflect Orbital now expects to launch its first satellite in April, according to the article. "But its grand vision is largely 'aspirational,' as its young founder, Ben Nowack, told me..." Reflect Orbital's Nowack describes a scene right out of sci-fi: An extremely bright star appears on the northern horizon and makes its way across the sky, illuminating a 5-kilometer circle on Earth, then setting on the southern horizon about five minutes later, just as another such "star" appears in the north. To make the night even brighter, a customer could make 10 "stars" appear at once in the north by ordering them on an app. Two such artificial stars are in development in Reflect Orbital's factory. Nowack showed them to me on a Zoom call. The first to launch is 50 feet across, but he plans later to build them three times that size. If all goes according to plan, he'll have 50,000 of them circling the Earth in 2035 at an altitude of around 400 miles.

Nowack plans to start selling the service "in mostly developing nations or places that don't have streetlights yet." Eventually, he thinks, he can illuminate major cities, turn solar fields and farms into round-the-clock operations for any business or municipality that pays for it. He likened his technology to the invention of crop irrigation thousands of years ago. "I see this as much the same thing," he said, arguing that people would no longer have to "wait for the sun to shine."
The article adds that Elon Musk's SpaceX "wants to launch as many as a million satellites to serve as orbiting data centers — 70 times the number of satellites now in orbit." (America's satellite-regulation Federal Communications Commission grants a "categorical exclusion" from environmental review to satellites on the grounds that their operations "normally do not have significant effects on the human environment.")

The public comment periods for the two proposals close on March 6 and March 9.

On February 24th, the Vera C. Rubin Observatory activated its automated alert system, sending out roughly 800,000 real-time notifications flagging asteroids, supernovae, flaring black holes and "other transient celestial events," reports Scientific American. And this is only the beginning -- that number is projected to climb into the millions as it continues scanning the ever-changing sky. From the report: The astronomical observatory equipped with world's largest camera hit a key milestone on February 24, when a complex data-processing system pushed hundreds of thousands of alerts out to scientists eager to pore over its most exciting sightings. The Vera C. Rubin Observatory began operations last year, capturing stunning, panoramic time-lapse views of the cosmos with ease. Rubin's first images, based on just 10 hours of observations, let space fans zoom seemingly forever into an overwhelmingly starry sky. But watchful astronomers were always awaiting the next step: the system that would automatically alert them to the most promising activity in the overhead sky amid the 1,000 or so enormous images that Rubin's telescope captures every night.

"We can detect everything that changes, moves and appears," said Yusra AlSayyad, an astronomer at Princeton University and Rubin's deputy associate director for data management, to Scientific American last summer. "It's way too much for one person to manually sift through and filter and monitor themselves." So even as they were designing and building the Rubin Observatory itself, scientists were also designing an alert system to help astronomers navigate the flood of data. As soon as the telescope began observations, the team started constructing a static reference image of the entire sky in impeccable detail.

Now the data processing systems that support the observatory are starting to automatically compare every new Rubin image to the corresponding section of that background template. The systems identify all of the differences, each of which is individually flagged. The algorithms can also distinguish between a potential supernova and a possible newfound asteroid, for example. Alerting the scientific community is the final, crucial step. Astronomers -- as well as members of the public -- can sign up for notifications based on the type of sighting they're interested in and the brightness of the observation in question. And now that the alerts system has gone live, users receive a tiny, fuzzy image with some astronomical metadata of each observation that fits their criteria -- all just a couple of minutes after Rubin captures the original image.

Researchers at Cortical Labs used living human neurons grown on a chip to learn how to play Doom in about a week. "While its performance is not up to par with humans, experts say it brings biological computers a step closer to useful real-world applications, like controlling robot arms," reports New Scientist. From the report: In 2021, the Australian company Cortical Labs used its neuron-powered computer chips to play Pong. The chips consisted of clumps of more than 800,000 living brain cells grown on top of microelectrode arrays that can both send and receive electrical signals. Researchers had to carefully train the chips to control the paddles on either side of the screen. Now, Cortical Labs has developed an interface that makes it easier to program these chips using the popular programming language Python. An independent developer, Sean Cole, then used Python to teach the chips to play Doom, which he did in around a week.

"Unlike the Pong work that we did a few years ago, which represented years of painstaking scientific effort, this demonstration has been done in a matter of days by someone who previously had relatively little expertise working directly with biology," says Brett Kagan of Cortical Labs. "It's this accessibility and this flexibility that makes it truly exciting."

The neuronal computer chip, which used about a quarter as many neurons as the Pong demonstration, played Doom better than a randomly firing player, but far below the performance of the best human players. However, it learnt much faster than traditional, silicon-based machine learning systems and should be able to improve its performance with newer learning algorithms, says Kagan. However, it's not useful to compare the chips with human brains, he says. "Yes, it's alive, and yes, it's biological, but really what it is being used as is a material that can process information in very special ways that we can't recreate in silicon." Cortical Labs posted a YouTube video showing its CL1 biological computer running Doom. There's also source code available on GitHub, with additional details in a README file.

Nasa announced on Friday radical changes to its delayed Artemis III mission to land humans back on the moon, as the US space agency grapples with technical glitches and criticism that it is trying to do too much too soon. From a report: The abrupt shift in strategy was laid out by the space agency's recently confirmed administrator, Jared Isaacman. Announcing the changes on Friday, he said that Nasa would introduce at least one new moon flight before attempting to put humans back on the lunar surface for the first time in more than half a century, in 2028.

The new, more incremental approach would give the Nasa team a chance to test flight and refine its technology. As part of the changes, the Artemis II mission to fly humans around the moon this year, without landing, would also be pushed back from its latest scheduled launch on 6 March to 1 April at the earliest.

"Everybody agrees this is the only way forward," Isaacman told reporters at a news conference. "I know this is how Nasa changed the world, and this is how Nasa is going to do it again."

sciencehabit quotes a report from Science Magazine: For decades, planetary scientists have pored over a mystery hidden within the Moon rocks retrieved by Apollo astronauts in the 1960s and '70s. Minerals in the rocks record the imprint of a magnetic field, nearly as powerful as Earth's, that existed more than 3.5 billion years ago and seemed to persist for millions of years. But generating a magnetic field requires a dynamo -- a churning, molten core -- and most researchers believed the Moon's tiny core would have long since cooled off, 1 billion years after it formed. Corroborating that picture are other ancient Moon rocks of about the same age that suggest the field was weak -- leaving planetary scientists baffled.

Now, researchers are proposing a new way to solve the puzzle. A paper published today in Nature Geoscience theorizes that between 3.5 billion and 4 billion years ago, blobs of titanium-rich magma melted episodically just above the core, rising in plumes that drove volcanic eruptions on the surface. By intermittently stirring up the Moon's core, these bouts of melting would have caused the Moon's magnetic field to flicker on in short, powerful bursts. The paper "links a few different concepts that people were thinking about separately, but hadn't actually brought together," says Sonia Tikoo, a planetary geophysicist at Stanford University who was not involved in the study.

Longtime Slashdot reader ArchieBunker shares a report from NBC News: NASA revealed that astronaut Mike Fincke was the crew member who suffered a medical incident at the International Space Station in January, which prompted the agency to carry out the first evacuation due to a medical issue in the space station's 25-year history. The rare decision to cut a mission short and bring Fincke and three other crew members home early made for a dramatic week in space early this year.

In a statement released by NASA "at the request of Fincke," the veteran astronaut said he experienced a medical event on Jan. 7 "that required immediate attention" from his space station crew members. "Thanks to their quick response and the guidance of our NASA flight surgeons, my status quickly stabilized," Fincke, 58, said in the statement. [...] In his statement, Fincke thanked his Crew-11 colleagues, along with NASA astronaut Chris Williams and Russian cosmonauts Sergey Kud-Sverchkov and Sergei Mikaev, who were also aboard the space station at the time and are still in space. Fincke also thanked the teams at NASA, SpaceX and the medical professionals at Scripps Memorial Hospital La Jolla. "Their professionalism and dedication ensured a positive outcome," he said.

Fincke ended his statement by saying he is "doing very well" and still actively involved with standard post-flight reconditioning at NASA's Johnson Space Center in Houston. "Spaceflight is an incredible privilege, and sometimes it reminds us just how human we are," he said. "Thank you for all your support."

The screeching sound that Scotch tape makes when you rip it off a surface -- that fingernails-on-a-chalkboard noise most people try not to think about -- is produced by shock waves from micro-cracks that travel across the peeling tape at supersonic speeds, according to a new paper published in Physical Review E.

Researchers led by Sigurdur Thoroddsen of King Abdullah University in Saudi Arabia used simultaneous high-speed imaging and synchronized microphones to capture both the propagating fractures and the sound waves they generate in the surrounding air. The team's earlier work, in 2010, had identified a sequence of transverse cracks racing across the width of the adhesive during peeling, and a 2024 follow-up established a direct correspondence between those cracks and the screeching sound, but neither study pinpointed a mechanism.

The new findings show that a partial vacuum forms between the tape and the surface as each crack opens, and because the crack moves faster than air can rush in to fill the void, the vacuum travels along until it reaches the tape's edge and collapses into the stationary air outside, producing a discrete sound pulse.

A 10-week-old boy named Hugo has become the first baby born in the UK from a womb transplanted from a deceased donor, after his mother Grace Bell -- who was born without a viable womb due to a condition called MRKH syndrome, which affects one in every 5,000 women -- underwent a 10-hour transplant operation at The Churchill Hospital in Oxford in June 2024.

Hugo was born just before Christmas 2025, weighing nearly 7lbs, at Queen Charlotte's and Chelsea Hospital in west London, following IVF treatment and embryo transfer at The Lister Fertility Clinic. Bell's transplant is one of three completed so far as part of a UK clinical research trial that plans to carry out 10 such procedures from deceased donors, and Hugo is the first baby born from any of them.
Earlier in 2025, a separate effort produced baby Amy, the first UK birth from a living womb donation -- her mother had received her older sister's womb in January 2023. Globally, more than 100 womb transplants have been performed, resulting in over 70 healthy births.

Climate scientists trying to predict how much hotter the planet will get have long grappled with a surprisingly stubborn problem -- clouds, which both reflect sunlight and trap heat, account for more than half the variation between climate predictions and are the main reason warming projections for the next 50 years range from 2 to 6 degrees Celsius.

Two research groups are now racing to close that gap using AI, though they disagree sharply on method. Tapio Schneider at Caltech built CLIMA, a model that uses machine learning to optimize cloud parameters within traditional physics equations; it will be unveiled at a conference in Japan in March. Chris Bretherton at the Allen Institute for AI took a different path -- his ACE2 neural network, released in 2024, learns from 50 years of atmospheric data and largely bypasses physics equations altogether.

A study published last week in PNAS found that people who regularly cause problems or make life difficult -- whom the researchers call "hasslers" -- are associated with measurably faster biological aging in those around them, at a rate of roughly 1.5% per additional hassler and about nine months of additional biological age relative to same-age peers.

The research drew on DNA methylation-based epigenetic clocks and ego-centric network data from a state-representative probability sample of 2,345 adults in Indiana, aged 18 to 103. Nearly 29% of respondents reported at least one hassler in their close network. The biological toll varied by relationship type: hasslers who were family members showed the strongest and most consistent associations with accelerated aging, while spouse hasslers showed no significant effect on either epigenetic measure.

The damage also went beyond aging clocks -- each additional hassler was associated with greater depression and anxiety severity, higher BMI, increased inflammation, and higher multimorbidity. When benchmarked against smoking, a major behavioral risk factor for aging, the hassler effect corresponded to roughly 13 to 17% of smoking's estimated impact on the same aging clocks.