Science – Page 4

Exploring an undersea terrain sculpted by glaciers and volcanoes

Science / Kris Guyer / December 21, 2024

Perhaps counterintuitively, sediment layers are more likely to remain intact on the seafloor than on land, so they can provide a better record of the region’s history. The seafloor is a more stable, oxygen-poor environment, reducing erosion and decomposition (two reasons scientists find far more fossils of marine creatures than land dwellers) and preserving finer details.

A close-up view of a core sample taken by a vibracorer. Scientists mark places they plan to inspect more closely with little flags. Credit: Alex Ingle / Schmidt Ocean Institute

Samples from different areas vary dramatically in time coverage, going back only to 2008 for some and back potentially more than 15,000 years for others due to wildly different sedimentation rates. Scientists will use techniques like radiocarbon dating to determine the ages of sediment layers in the core samples.

ROV SuBastian spotted a helmet jellyfish during the expedition. These photophobic (light avoidant) creatures glow via bioluminescence. Credit: Schmidt Ocean Institute

Microscopic analysis of the sediment cores will also help the team analyze the way the eruption affected marine creatures and the chemistry of the seafloor.

“There’s a wide variety of life and sediment types found at the different sites we surveyed,” said Alastair Hodgetts, a physical volcanologist and geologist at the University of Edinburgh, who participated in the expedition. “The oldest place we visited—an area scarred by ancient glacier movement—is a fossilized seascape that was completely unexpected.”

In a region beyond the dunes, ocean currents have kept the seafloor clear of sediment. That preserves seabed features left by the retreat of ice sheets at the end of the last glaciation. Credit: Rodrigo Fernández / CODEX Project

This feature, too, tells scientists about the way the water moves. Currents flowing over an area that was eroded long ago by a glacier sweep sediment away, keeping the ancient terrain visible.

“I’m very interested in analyzing seismic data and correlating it with the layers of sediment in the core samples to create a timeline of geological events in the area,” said Giulia Matilde Ferrante, a geophysicist at Italy’s National Institute of Oceanography and Applied Geophysics, who co-led the expedition. “Reconstructing the past in this way will help us better understand the sediment history and landscape changes in the region.”

In this post-apocalyptic scene, captured June 20, 2008, a thick layer of ash covers the town of Chaitén as the volcano continues to erupt in the background. Around 5,000 people evacuated, and resettlement efforts didn’t begin until the following year. Credit: Javier Rubilar

The team has already gathered measurements of the amount of sediment the eruption delivered to the sea. Now they’ll work to determine whether older layers of sediment record earlier, unknown events similar to the 2008 eruption.

“Better understanding past volcanic events, revealing things like how far away an eruption reached, and how common, severe, and predictable eruptions are, will help to plan for future events and reduce the impacts they have on local communities,” Watt said.

Ashley writes about space for a contractor for NASA’s Goddard Space Flight Center by day and freelances as an environmental writer. She holds master’s degrees in space studies from The University of North Dakota and science writing from The Johns Hopkins University. She writes most of her articles with a baby on her lap.

Exploring an undersea terrain sculpted by glaciers and volcanoes Read More »

Louisiana bars health dept. from promoting flu, COVID, mpox vaccines: Report

anti-vaccine, COVID-19, flu, health, health department, KFF Health News, Louisiana, mpox, NPR, public health, Science, vaccines / Tim Belzer / December 21, 2024

Louisiana’s health department has been barred from advertising or promoting vaccines for flu, COVID-19, and mpox, according to reporting by NPR, KFF Health News, and New Orleans Public Radio WWNO.

Their investigative report—based on interviews with multiple health department employees who spoke on the condition of anonymity for fear of retaliation—revealed that employees were told of the startling policy change in meetings in October and November and that the policy would be implemented quietly and not put into writing.

Ars Technica has contacted the health department for comment and will update this post with any new information.

The health department provided a statement to NPR saying that it has been “reevaluating both the state’s public health priorities as well as our messaging around vaccine promotion, especially for COVID-19 and influenza.” The statement described the change as a move “away from one-size-fits-all paternalistic guidance” to a stance in which “immunization for any vaccine, along with practices like mask wearing and social distancing, are an individual’s personal choice.”

According to employees, the new policy cancelled standard fall flu vaccination events this year and affects every other aspect of the health department’s work, as NPR explained:

“Employees could not send out press releases, give interviews, hold vaccine events, give presentations or create social media posts encouraging the public to get the vaccines. They also could not put up signs at the department’s clinics that COVID, flu or mpox vaccines were available on site.”

“We’re really talking about deaths”

The change comes amid a dangerous swell of anti-vaccine sentiment and misinformation in Louisiana and across the country. President-elect Trump has picked Robert F. Kennedy Jr.—a high-profile anti-vaccine advocate and one of the most prolific spreaders of vaccine misinformation—to head the US Department of Health and Human Services.

Louisiana bars health dept. from promoting flu, COVID, mpox vaccines: Report Read More »

Rocket Report: ULA has a wild idea; Starliner crew will stay in orbit even longer

rocket report, Science, Space / Tim Belzer / December 20, 2024

ULA’s Vulcan rocket is at least several months away from flying again, and Stoke names its engine.

Stoke Space’s Zenith booster engine fires on a test stand at Moses Lake, Washington. Credit: Stoke Space

Welcome to Edition 7.24 of the Rocket Report! This is the last Rocket Report of the year, and what a year it’s been. So far, there have been 244 rocket launches to successfully reach orbit this year, a record for annual launch activity. And there are still a couple of weeks to go before the calendar turns to 2025. Time is running out for Blue Origin to launch its first heavy-lift New Glenn rocket this year, but if it flies before January 1, it will certainly be one of the top space stories of 2024.

As always, we welcome reader submissions. If you don’t want to miss an issue, please subscribe using the box below (the form will not appear on AMP-enabled versions of the site). Each report will include information on small-, medium-, and heavy-lift rockets as well as a quick look ahead at the next three launches on the calendar.

Corkscrew in the sky. A Japanese space startup said its second attempt to launch a rocket carrying small satellites into orbit had been terminated minutes after liftoff Wednesday and destroyed itself again, nine months after the company’s first launch attempt in an explosion, the Associated Press reports. The startup that developed the rocket, named Space One, launched the Kairos rocket from a privately owned coastal spaceport in Japan’s Kansai region. Company executive and space engineer Mamoru Endo said an abnormality in the first stage engine nozzle or its control system is likely to have caused an unstable flight of the rocket, which started spiraling in mid-flight and eventually destroyed itself about three minutes after liftoff, using its autonomous safety mechanism.

0-for-2 … The launch failure this week followed the first attempt to launch the Kairos rocket in March, when the launcher exploded just five seconds after liftoff. An investigation into the failed launch in March concluded the rocket’s autonomous destruct system activated after detecting its solid-fueled first stage wasn’t generating as much thrust as expected. The Kairos rocket is Japan’s first privately funded orbital-class rocket, capable of placing payloads up to 550 pounds (250 kilograms) into low-Earth orbit. (submitted by Jay500001, Ken the Bin, and EllPeaTea)

A fit check for Themis. ArianeGroup has brought the main elements of the Themis reusable booster demonstrator together for the first time in France during a “full-fit check,” European Spaceflight reports. This milestone paves the way for the demonstrator’s inaugural test, which is expected to take place in 2025. Themis, which is funded by the European Space Agency, is designed to test vertical launch and landing capabilities with a new methane-fueled rocket engine. According to ESA, the full-fit check is one of the final steps in the development phase of Themis.

Slow progress … ESA signed the contract with ArianeGroup for the Themis program in 2020, and at that time, the program’s schedule called for initial low-altitude hop tests in 2022. It’s now taken more than double the time officials originally projected to get the Themis rocket airborne. The first up-and-down hops will be based at the Esrange Space Center in Sweden, and will use the vehicle ArianeGroup is assembling now in France. A second Themis rocket will be built for medium-altitude tests from Esrange, and finally, a three-engine version of Themis will fly on high-altitude tests from the Guiana Space Center in South America. At the rate this program is proceeding, it’s fair to ask if Themis will complete a full-envelope launch and landing demonstration before the end of the decade, if it ever does. (submitted by Ken the Bin)

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Baguette One is going critical. French launch startup HyPrSpace has announced that it has completed preliminary design reviews for its Baguette One and Orbital Baguette One (OB-1) rockets, European Spaceflight reports. Baguette One will be a suborbital demonstrator for the OB-1 rocket, designed to use a hybrid propulsion system that combines liquid and solid propellants and doesn’t require a turbopump. With the preliminary design complete, HyPrSpace said it is moving on to the critical design phase for both rockets, a stage of development where detailed engineering plans are finalized and components are prepared for manufacturing.

Heating the oven … HyPrSpace has previously stated the Orbital Baguette One rocket will be capable of delivering a payload of up to 550 pounds (250 kilograms) to low-Earth orbit. Last year, the startup announced it raised 35 million euros in funding, primarily from the French government, to complete the critical design phase of the OB-1 rocket and launch the Baguette One on a suborbital test flight. HyPrSpace has not provided an updated schedule for the first flight of either rocket. (submitted by Ken the Bin)

A new player on the scene. RTX weapons arm Raytheon and defense startup Ursa Major Technologies have completed two successful test flights of a missile propelled by a new solid rocket motor, Breaking Defense reports. The two test flights, held at Naval Air Weapons Station China Lake in California, involved a Raytheon-made missile propelled by an Ursa Major solid rocket motor measuring less than 10 inches in diameter, according to Dan Jablonsky, Ursa Major’s CEO. Details about the missile are shrouded in mystery, and Raytheon officials referred questions on the matter to the Army.

Joining the club … The US military is interested in fostering the development of a third supplier of solid rocket propulsion for weapons systems. Right now, only Northrop Grumman and L3Harris’s Aerojet Rocketdyne are available as solid rocket vendors, and they have struggled to keep up with the demand for weapons systems, especially to support the war in Ukraine. Ursa Major is one of several US-based startups entering the solid rocket propulsion market. “There is a new player on the scene in the solid rocket motor industry,” Jablonsky said. “This is an Army program that we’ve been working on with Raytheon. In this particular program, we went from concept and design to firing and flight on the range in just under four months, which is lightning fast.” (submitted by Ken the Bin)

SpaceX’s rapid response. In a mission veiled in secrecy, a SpaceX Falcon 9 rocket lifted off Monday from Cape Canaveral Space Force Station, Florida, sending a military Global Positioning System (GPS) satellite to a medium orbit about 12,000 miles above Earth, Space News reports. Named Rapid Response Trailblazer-1 (RRT-1), this mission was a US national security space launch and was also intended to demonstrate military capabilities to condense a typical two-year mission planning cycle to less than six months. The payload, GPS III SV-07, is the seventh satellite of the GPS III constellation, built by Lockheed Martin. The spacecraft was in storage awaiting a launch on United Launch Alliance’s Vulcan rocket.

Tightening the timeline … “We decided to pull SV-07 out of storage and try to get it to the launch pad as quickly as possible,” Col. James Horne, senior material leader for launch execution at the US Space Force’s Space Systems Command, told Space News. “It’s our way of demonstrating that we can be responsive to operator needs.” Rather than the typical mission cycle of two years, SpaceX, Lockheed Martin, and the Space Force worked together to prep this GPS satellite for launch in a handful of months. Military officials decided to launch SV-07 with SpaceX as ULA’s Vulcan rocket faced delays in becoming certified to launch national security payloads. According to Space News, Horne emphasized that this move was less about Vulcan delays and more about testing the boundaries of the NSSL program’s flexibility. “This is a way for us to demonstrate to adversaries that we can be responsive,” he said. Because SV-07 was switched to SpaceX, ULA will get to launch GPS III SV-10, originally assigned to SpaceX. (submitted by Ken the Bin and EllPeaTea)

An update on Butch and Suni. NASA has announced that it is delaying the SpaceX Crew-10 launch, a move that will keep astronauts Butch Wilmore and Suni Williams—who already had their stay aboard the International Space Station unexpectedly extended—in orbit even longer, CNN reports. Williams and Wilmore launched to space in June, piloting the first crewed test flight of Boeing’s Starliner spacecraft. Their trip, expected to last about a week, ballooned into a months-long assignment after their vehicle experienced technical issues en route to the space station and NASA determined it would be too risky to bring them home aboard the Starliner.

Nearly 10 months in orbit … The astronauts stayed aboard the space station as the Starliner spacecraft safely returned to Earth in September, and NASA shuffled the station’s schedule of visiting vehicles to allow Wilmore and Williams to come home on a SpaceX Dragon spacecraft with two crewmates to end the Crew-9 mission in February, soon after the arrival of Crew-10. Now, Crew-10 will get off the ground at least a month later than expected because NASA and SpaceX teams need “time to complete processing on a new Dragon spacecraft for the mission,” the space agency said. (submitted by Ken the Bin)

Stoke Space names its engine. Stoke Space, the only other company besides SpaceX developing a fully reusable orbital rocket, has revealed the name of the methane-fueled engine that will power the vehicle’s booster stage. “Say hello to Zenith, our full-flow staged-combustion booster engine, built to power Nova to orbit,” Stoke Space wrote in a post on X. The naming announcement came a few days after Stoke Space said it hot-fired the “Block 2” or “flight layout” version of the main engine on a test stand in Moses Lake, Washington.

Stoked by the progress … “As we build towards the future of space mobility, we’re building on top of the pinnacle–the zenith–of rocket engine cycles: full-flow staged combustion,” Stoke Space said. Only a handful of rocket engines have been designed to use the full-flow staged combustion cycle, and only one has actually flown on a rocket: SpaceX’s Raptor. Seven Zenith engines will power the first stage of the Nova rocket when it takes off from Cape Canaveral, Florida. A hydrogen-fueled propulsion system will power the second stage of Nova, which is designed to launch up to 5 metric tons (11,000 pounds) of payload to low-Earth orbit.

Upgrades coming for Vega. The European Space Agency (ESA) has signed 350 million euros in contracts with Avio to further evolve the Vega launcher family,” Aviation Week & Space Technology reports. The contracts cover the development of the Vega-E and upgrades to the current Vega-C’s ground infrastructure to increase the launch cadence. Vega-E, scheduled to debut in 2027, will replace the Vega-C rocket’s third and fourth stages with a single methane-fueled upper stage under development by Avio. It will also offer a 30 percent increase in Vega’s payload lift capability, and will launch from a new complex to be built on the former Ariane 5 launch pad at the European-run Guiana Space Center in South America.

Adaptations … The fresh tranche of funding from ESA will also pay for Avio’s work to “adapt” the former Ariane 5 integration building at the spaceport in French Guiana, according to ESA. “This will allow technicians to work on two rockets being assembled simultaneously–one on the launch pad and one in the new assembly building–and run two launch campaigns in parallel,” ESA said. (submitted by Ken the Bin and EllPeaTea)

New Glenn coming alive. In a widely anticipated test, Blue Origin will soon ignite the seven main engines on its New Glenn rocket at Launch Complex-36 in Florida, Ars reports. Sources indicated this hot-fire test might occur as soon as Thursday, but it didn’t happen. Instead, Blue Origin’s launch team loaded cryogenic propellants into the New Glenn rocket on the launch pad, but stopped short of igniting the main engines.

Racing the clock … The hot-fire is the final test the company must complete before verifying the massive rocket is ready for its debut flight, and it is the most dynamic. This will be the first time Blue Origin has ever test-fired the BE-7 engines altogether. Theoretically, at least, it remains possible that Blue Origin could launch New Glenn this year—and the company’s urgency certainly speaks to this. On social media this week, some Blue Origin employees noted that they were being asked to work on Christmas Day this year in Florida.

China begins building a new megaconstellation. The first batch of Internet satellites for China’s Guowang megaconstellation launched Monday on the country’s heavy-lift Long March 5B rocket, Ars reports. The satellites are the first of up to 13,000 spacecraft a consortium of Chinese companies plans to build and launch over the next decade. The Guowang fleet will beam low-latency high-speed Internet signals in an architecture similar to SpaceX’s Starlink network, although Chinese officials haven’t laid out any specifics, such as target markets, service specifications, or user terminals.

No falling debris, this time … China used its most powerful operational rocket, the Long March 5B, for the job of launching the first 10 Guowang satellites this week. The Long March 5B’s large core stage, which entered orbit on the rocket’s previous missions and triggered concerns about falling space debris, fell into a predetermined location in the sea downrange from the launch site. The difference for this mission was the addition of the Yuanzheng 2 upper stage, which gave the rocket’s payloads the extra oomph they needed to reach their targeted low-Earth orbit. (submitted by Ken the Bin and EllPeaTea)

Elon Musk’s security clearance under review. A new investigation from The New York Times suggests that SpaceX founder Elon Musk has not been reporting his travel activities and other information to the Department of Defense as required by his top-secret clearance, Ars reports. According to the newspaper, concerns about Musk’s reporting practices have led to reviews by three different bodies within the military: the Air Force, the Office of the Under Secretary of Defense for Intelligence and Security, and the Defense Department Office of Inspector General. However, none of the federal agencies cited in the Times article has accused Musk of disclosing classified material.

It won’t matter … Since 2021, Musk has failed to self-report details of his life, including travel activities, people he has met, and drug use, according to the Times. The government is also concerned that SpaceX did not ensure Musk’s compliance with the reporting rules. Musk’s national security profile has risen following his deep-pocketed and full-throated support of Donald Trump, who won the US presidential campaign in November and will be sworn into office next month. After this inauguration, Trump will have the power to grant security clearance to whomever he wishes.

ULA’s CEO has a pretty wild idea. Ars published a feature story last week examining the US Space Force’s new embrace of offensive weapons in space. In the story, Ars discusses concepts for different types of space weapons, including placing roving “defender” satellites into orbit, with the sole purpose of guarding high-value US satellites against an attack. Tory Bruno, CEO of United Launch Alliance, wrote about the defender concept in a Medium post earlier this month. He added more detail in a recent conversation with reporters, describing the defender concept as “a lightning-fast, long-range, lethal, if necessary, vehicle to defend our assets on orbit.” And guess what? The Centaur upper stage for ULA’s own Vulcan rocket could do the job just fine, according to Bruno.

Death throes or a smart pivot? … A space tug or upper stage like the Centaur could be left in orbit after a launch to respond to threats against US or allied satellites, Bruno said. These wouldn’t be able to effectively defend a spacecraft against a ground-based anti-satellite missile, which can launch without warning. But a space-based attack might involve an enemy satellite taking days or weeks to move close to a US satellite due to limitations in maneuverability and the tyranny of orbital mechanics. Several launch companies have recently pitched their rockets as solutions for weapons testing, including Rocket Lab and ABL. But the concept proposed by Bruno would take ULA far from its core business, where its efforts to compete with SpaceX have often fallen short. However, the competition is still alive, as shown by a comment from SpaceX’s vice president of Falcon launch vehicles, Jon Edwards. In response to Ars’s story, Edwards wrote on X: “The pivot to ‘interceptor’ or ‘target vehicle’ is a common final act of a launch vehicle in its death throes.” (submitted by Ken the Bin)

Vulcan is months away from flying again. Speaking of ULA, here’s an update on the next flight of the company’s Vulcan rocket. The first national security mission on Vulcan might not launch until April 2025 at the earliest, Spaceflight Now reports. This will be the third flight of a Vulcan rocket, following two test flights this year to gather data for the US Space Force to certify the rocket for national security missions. On the second flight, the nozzle fell off one of Vulcan’s solid rocket boosters shortly after liftoff, but the rocket successfully continued its climb into orbit. The anomaly prompted an investigation, and ULA says it is close to determining the root cause.

Stretching the timeline … The Space Force’s certification review of Vulcan is taking longer than anticipated. “The government team has not completed its technical evaluation of the certification criteria and is working closely with ULA on additional data required to complete this evaluation,” a Space Force spokesperson told Spaceflight Now. “The government anticipates completion of its evaluation and certification in the first quarter of calendar year 2025.” The spokesperson said this means the launch of a US military navigation test satellite on the third Vulcan rocket is now slated for the second quarter of next year. (submitted by Ken the Bin and EllPeaTea)

Next three launches

Dec. 21: Falcon 9 | “Astranis: From One to Many” | Cape Canaveral Space Force Station, Florida | 03: 39 UTC

Dec. 21: Falcon 9 | Bandwagon 2 | Vandenberg Space Force Base, California | 11: 34 UTC

Dec. 21: Electron | “Owl The Way Up” | Māhia Peninsula, New Zealand | 13: 00 UTC

Stephen Clark is a space reporter at Ars Technica, covering private space companies and the world’s space agencies. Stephen writes about the nexus of technology, science, policy, and business on and off the planet.

Rocket Report: ULA has a wild idea; Starliner crew will stay in orbit even longer Read More »

Louisiana resident in critical condition with H5N1 bird flu

bird flu, CDC, H5N1, health, Infectious disease, Louisiana, Science / Tim Belzer / December 18, 2024

The Louisiana resident infected with H5N1 bird flu is hospitalized in critical condition and suffering from severe respiratory symptoms, the Louisiana health department revealed Wednesday.

The health department had reported the presumptive positive case on Friday and noted the person was hospitalized, as Ars reported. But a spokesperson had, at the time, declined to provide Ars with the patient’s condition or further details, citing patient confidentiality and an ongoing public health investigation.

This morning, the Centers for Disease Control and Prevention announced that it had confirmed the state’s H5N1 testing and determined that the case “marks the first instance of severe illness linked to the virus in the United States.”

In a follow-up, the health department spokesperson Emma Herrock was able to release more information about the case. In addition to being in critical condition with severe respiratory symptoms, the person is reported to be over the age of 65 and has underlying health conditions.

Further, the CDC collected partial genetic data of the H5N1 strain infecting the patient, finding it to be of D1.1. genotype, which has been detected in wild birds and some poultry in the US. Notably, it is the same genotype seen in a Canadian teenager who was also hospitalized in critical condition from the virus last month. The D1.1. genotype is not the same as the one circulating in US dairy cows, which is the B3.13 genotype.

Louisiana resident in critical condition with H5N1 bird flu Read More »

“Unprecedented” decline in teen drug use continues, surprising experts

adolescent, alcohol, Drug use, health, illicit drugs, marijuana, nicotine, Science, Teens / Paul Patrick / December 17, 2024

A new era

“Kids who were in eighth grade at the start of the pandemic will be graduating from high school this year, and this unique cohort has ushered in the lowest rates of substance use we’ve seen in decades,” Miech noted.

For alcohol, use in the past 12 months among eighth graders was at 12.9 percent in 2024, similar to 2023 levels, which are all-time lows. For 10th graders, the rate dropped significantly from 30.6 percent in 2023 to 26.1 percent, and for 12th graders, from 45.7 percent to 41.7 percent—both record lows.

For nicotine vaping, rates fell for 10th graders (from 17.5 percent to 15.4 percent) and remained at low levels for eighth and 12th graders. For marijuana, use remained low for eighth and 10th graders and fell significantly for 12th graders (from 29 percent to 25.8 percent). All three grades are at lows not seen since 1990.

For abstainers from alcohol, marijuana, and nicotine in the prior 30 days, the rate among eighth graders hit 90 percent, up from 87 percent in 2017, when it was first measured. The rate was 80 percent among 10th graders, up from 69 percent in 2017, and 67 percent for 12th graders, up from 53 percent in 2017.

“This trend in the reduction of substance use among teenagers is unprecedented,” Nora Volkow, director of NIH’s National Institute on Drug Abuse (NIDA), said. “We must continue to investigate factors that have contributed to this lowered risk of substance use to tailor interventions to support the continuation of this trend.”

“Unprecedented” decline in teen drug use continues, surprising experts Read More »

$huge-math-error-corrected-in-black-plastic-study;-authors-say-it-doesn’t-matter$

Huge math error corrected in black plastic study; authors say it doesn’t matter

black plastic, chemosphere, electronic plastic, EPA, flame retardants, health, plastic, plastic recycling, Science, Toxicology, waste / Kris Guyer / December 16, 2024

Ars has reached out to the lead author, Megan Liu, but has not received a response. Liu works for the environmental health advocacy group Toxic-Free Future, which led the study.

The study highlighted that flame retardants used in plastic electronics may, in some instances, be recycled into household items.

“Companies continue to use toxic flame retardants in plastic electronics, and that’s resulting in unexpected and unnecessary toxic exposures,” Liu said in a press release from October. “These cancer-causing chemicals shouldn’t be used to begin with, but with recycling, they are entering our environment and our homes in more ways than one. The high levels we found are concerning.”

BDE-209, aka decabromodiphenyl ether or deca-BDE, was a dominant component of TV and computer housings before it was banned by the European Union in 2006 and some US states in 2007. China only began restricting BDE-209 in 2023. The flame retardant is linked to carcinogenicity, endocrine disruption, neurotoxicity, and reproductive harm.

Uncommon contaminant

The presence of such toxic compounds in household items is important for noting the potential hazards in the plastic waste stream. However, in addition to finding levels that were an order of magnitude below safe limits, the study also suggested that the contamination is not very common.

The study examined 203 black plastic household products, including 109 kitchen utensils, 36 toys, 30 hair accessories, and 28 food serviceware products. Of those 203 products, only 20 (10 percent) had any bromine-containing compounds at levels that might indicate contamination from bromine-based flame retardants, like BDE-209. Of the 109 kitchen utensils tested, only nine (8 percent) contained concerning bromine levels.

“[A] minority of black plastic products are contaminated at levels >50 ppm [bromine],” the study states.

But that’s just bromine compounds. Overall, only 14 of the 203 products contained BDE-209 specifically.

The product that contained the highest level of bromine compounds was a disposable sushi tray at 18,600 ppm. Given that heating is a significant contributor to chemical leaching, it’s unclear what exposure risk the sushi tray poses. Of the 28 food serviceware products assessed in the study, the sushi tray was only one of two found to contain bromine compounds. The other was a fast food tray that was at the threshold of contamination with 51 ppm.

Huge math error corrected in black plastic study; authors say it doesn’t matter Read More »

Bird flu jumps from birds to human in Louisiana; patient hospitalized

bird flu, H5N1, health, Science / Tim Belzer / December 13, 2024

A person in Louisiana is hospitalized with H5N1 bird flu after having contact with sick and dying birds suspected of carrying the virus, state health officials announced Friday.

It is the first human H5N1 case detected in Louisiana. For now, the case is considered a “presumptive” positive until testing is confirmed by the Centers for Disease Control and Prevention. Health officials say that the risk to the public is low but caution people to stay away from any sick or dead birds.

Although the person has been hospitalized, their condition was not immediately reported. It’s also unclear what kind of birds the person had contact with—wild, backyard, or commercial birds. Ars has reached out to Louisiana’s health department and will update this piece with any additional information.

The case is just the latest amid H5N1’s global and domestic rampage. The virus has been ravaging birds of all sorts in the US since early 2022 and spilling over to a surprisingly wide range of mammals. In March this year, officials detected an unprecedented leap to dairy cows, which has since caused a nationwide outbreak. The virus is currently sweeping through California, the country’s largest dairy producer.

To date, at least 845 herds across 16 states have contracted the virus since March, including 630 in California, which detected its first dairy infections in late August.

Human cases

At least 60 people in the US have been infected amid the viral spread this year. But the new case in Louisiana stands out. To date, nearly all of the human cases have been among poultry and dairy workers—unlike the new case in Louisiana— and almost all have been mild—also unlike the new case. Most of the cases have involved conjunctivitis—pink eye—and/or mild respiratory and flu-like symptoms.

There was a case in a patient in Missouri who was hospitalized. However, that person had underlying health conditions, and it’s unclear if H5N1 was the cause of their hospitalization or merely an incidental finding. It remains unknown how the person contracted the virus. An extensive investigation found no animal or other exposure that could explain the infection.

Bird flu jumps from birds to human in Louisiana; patient hospitalized Read More »

The US military is now talking openly about going on the attack in space

chance saltzman, Features, military space, Science, Space, US Space Force / Rejus Almole / December 13, 2024

Mastalir said China is “copying the US playbook” with the way it integrates satellites into more conventional military operations on land, in the air, and at sea. “Their specific goals are to be able to track and target US high-value assets at the time and place of their choosing,” Mastalir said.

China’s strategy, known as Anti-Access/Area Denial, or A2AD, is centered on preventing US forces from accessing international waters extending hundreds or thousands of miles from mainland China. Some of the islands occupied by China within the last 15 years are closer to the Philippines, another treaty ally, than to China itself.

The A2AD strategy first “extended to the first island chain (bounded by the Philippines), and now the second island chain (extending to the US territory of Guam), and eventually all the way to the West Coast of California,” Mastalir said.

US officials say China has based anti-ship, anti-air, and anti-ballistic weapons in the region, and many of these systems rely on satellite tracking and targeting. Mastalir said his priority at Indo-Pacific Command, headquartered in Hawaii, is to defend US and allied satellites, or “blue assets,” and challenge “red assets” to break the Chinese military’s “long-range kill chains and protect the joint force from space-enabled attack.”

What this means is the Space Force wants to have the ability to disable or destroy the satellites China would use to provide communication, command, tracking, navigation, or surveillance support during an attack against the US or its allies.

Buildings and structures are seen on October 25, 2022, on an artificial island built by China on Subi Reef in the Spratly Islands of the South China Sea. China has progressively asserted its claim of ownership over disputed islands in the region. Credit: Ezra Acayan/Getty Images

Mastalir said he believes China’s space-based capabilities are “sufficient” to achieve the country’s military ambitions, whatever they are. “The sophistication of their sensors is certainly continuing to increase—the interconnectedness, the interoperability. They’re a pacing challenge for a reason,” he said.

“We’re seeing all signs point to being able to target US aircraft carriers… high-value assets in the air like tankers, AWACS (Airborne Warning And Control System),” Mastalir said. “This is a strategy to keep the US from intervening, and that’s what their space architecture is.”

That’s not acceptable to Pentagon officials, so Space Force personnel are now training for orbital warfare. Just don’t expect to know the specifics of any of these weapons systems any time soon.

“The details of that? No, you’re not going to get that from any war-fighting organization—’let me tell you precisely how I intend to attack an adversary so that they can respond and counter that’—those aren’t discussions we’re going to have,” Saltzman said. “We’re still going to protect some of those (details), but broadly, from an operational concept, we are going to be ready to contest space.”

A new administration

The Space Force will likely receive new policy directives after President-elect Donald Trump takes office in January. The Trump transition team hasn’t identified any changes coming for the Space Force, but a list of policy proposals known as Project 2025 may offer some clues.

Published by the Heritage Foundation, a conservative think tank, Project 2025 calls for the Pentagon to pivot the Space Force from a mostly defensive posture toward offensive weapons systems. Christopher Miller, who served as acting secretary of defense in the first Trump administration, authored the military section of Project 2025.

Miller wrote that the Space Force should “reestablish offensive capabilities to guarantee a favorable balance of forces, efficiently manage the full deterrence spectrum, and seriously complicate enemy calculations of a successful first strike against US space assets.”

Trump disavowed Project 2025 during the campaign, but since the election, he has nominated several of the policy agenda’s authors and contributors to key administration posts.

Saltzman met with Trump last month while attending a launch of SpaceX’s Starship rocket in Texas, but he said the encounter was incidental. Saltzman was already there for discussions with SpaceX officials, and Trump’s travel plans only became known the day before the launch.

The conversation with Trump at the Starship launch didn’t touch on any policy details, according to Saltzman. He added that the Space Force hasn’t yet had any formal discussions with the Trump transition team.

Regardless of the direction Trump takes with the Space Force, Saltzman said the service is already thinking about what to do to maintain what the Pentagon now calls “space superiority”—a twist on the term air superiority, which might have seemed equally as fanciful at the dawn of military aviation more than a century ago.

“That’s the reason we’re the Space Force,” Saltzman said. “So administration to administration, that’s still going to be true. Now, it’s just about resourcing and the discussions about what we want to do and when we want to do it, and we’re ready to have those discussions.”

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Americans spend more years being unhealthy than people in any other country

disability, disease, health, health care, life expectancy, lifespan, Science, us / Kris Guyer / December 13, 2024

For the new study, researchers at the Mayo Clinic analyzed health statistics collected by the World Health Organization. The resource included data from 183 countries, allowing the researchers to compare countries’ life expectancy and healthspans, which are calculated by years of life weighted by health status.

Longer, but not better

Overall, the researchers saw lifespan-healthspan gaps grow around the world, with the average gap rising from 8.5 years in 2000 to 9.6 years in 2019. Global life expectancy rose 6.5 years, to about 73 years, while healthspans only rose 5.4 years in that time, to around 63 years.

But the US was a notable outlier, with its gap growing from 10.9 years to 12.4 years, a 29 percent higher gap than the global mean.

The gap was most notable for women—a trend seen around the world. Between 2000 and 2019, US women saw their life expectancy rise 1.5 years, from 79.2 to 80.7 years, but they saw no change in their healthspans. Women’s lifespan-healthspan gap rose from 12.2 years to 13.7 years. For US men, life expectancy rose 2.2 years, from 74.1 to 76.3 years, and their healthspans also increased 0.6 years. Their lifespan-healthspan gap in 2019 was 11.1 years, 2.6 years shorter than women’s.

The conditions most responsible for US disease burden included mental and substance use disorders, plus musculoskeletal diseases. For women, the biggest contributors were musculoskeletal, genitourinary, and neurological diseases.

While the US presented the most extreme example, the researchers note that the global trends seem to present a “disease paradox whereby reduced acute mortality exposes survivors to an increased burden of chronic disease.”

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Generating power with a thin, flexible thermoelectric film

cooling, materials science, power, Science, thermoelectric material / Rejus Almole / December 12, 2024

The No. 1 nuisance with smartphones and smartwatches is that we need to charge them every day. As warm-blooded creatures, however, we generate heat all the time, and that heat can be converted into electricity for some of the electronic gadgetry we carry.

Flexible thermoelectric devices, or F-TEDs, can convert thermal energy into electric power. The problem is that F-TEDs weren’t actually flexible enough to comfortably wear or efficient enough to power even a smartwatch. They were also very expensive to make.

But now, a team of Australian researchers thinks they finally achieved a breakthrough that might take F-TEDs off the ground.

“The power generated by the flexible thermoelectric film we have created would not be enough to charge a smartphone but should be enough to keep a smartwatch going,” said Zhi-Gang Chen, a professor at Queensland University of Technology in Brisbane, Australia. Does that mean we have reached a point where it would be possible to make a thermoelectric Apple Watch band that could keep the watch charged all the time? “It would take some industrial engineering and optimization, but we can definitely achieve a smartwatch band like that,” Chen said.

Manufacturing heaven

Thermoelectric generators producing enough power to run something like an Apple Watch were, so far, made with rigid bulk materials. The obvious problem with them was that nobody would want to wear a metal slab on their wrist or run a power cable from anywhere else to their watch. Flexible thermoelectric devices, on the other hand, were perfectly wearable but offered efficiencies that made them good for low-power health-monitoring electronics rather than more power-hungry hardware like smartwatches.

Back in 2021, generating 35 microwatts per square centimeter in a wristband worn during a typical walk outside was impressive enough to land your research paper in Nature. Today, Chen and his colleagues made a flexible thermoelectric device that performed over 34 times better at room temperature. “To the best of our knowledge, we hold a current record in this field,” Chen says.

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Studies pin down exactly when humans and Neanderthals swapped DNA

ancient DNA, ancient genomics, ancient people did stuff, anthropology, Archaeology, Neanderthals, out of africa, Science / Tim Belzer / December 12, 2024

We may owe our tiny sliver of Neanderthal DNA to just a couple of hundred Neanderthals.

The artist’s illustration shows what the six people buried at the Ranis site, who lived between 49, 500 and 41,000 years ago, may have looked like. Two of these people are mother and daughter, and the mother is a distant cousin (or perhaps a great-great-grandparent or great-great-grandchild) to a woman whose skull was found 130 kilometers away in what’s now Czechia. Credit: Sumer et al. 2024

Two recent studies suggest that the gene flow (as the young people call it these days) between Neanderthals and our species happened during a short period sometime between 50,000 and 43,500 years ago. The studies, which share several co-authors, suggest that our torrid history with Neanderthals may have been shorter than we thought.

Pinpointing exactly when Neanderthals met H. sapiens

Max Planck Institute of Evolutionary Anthropology scientist Leonardo Iasi and his colleagues examined the genomes of 59 people who lived in Europe between 45,000 and 2,200 years ago, plus those of 275 modern people whose ancestors hailed from all over the world. The researchers cataloged the segments of Neanderthal DNA in each person’s genome, then compared them to see where those segments appeared and how that changed over time and distance. This revealed how Neanderthal ancestry got passed around as people spread around the world and provided an estimate of when it all started.

“We tried to compare where in the genomes these [Neanderthal segments] occur and if the positions are shared among individuals or if there are many unique segments that you find [in people from different places],” said University of California Berkeley geneticist Priya Moorjani in a recent press conference. “We find the majority of the segments are shared, and that would be consistent with the fact that there was a single gene flow event.”

That event wasn’t quite a one-night stand; in this case, a “gene flow event” is a period of centuries or millennia when Neanderthals and Homo sapiens must have been in close contact (obviously very close, in some cases). Iasi and his colleagues’ results suggest that happened between 50,500 and 43,000 years ago. But it’s quite different from our history with another closely related hominin species, the now-extinct Denisovans, with whom different Homo sapiens groups met and mingled at least twice on our way to taking over the world.

In a second study, Arev Sümer (also of the Max Planck Institute) and her colleagues found something very similar in the genomes of people who lived 49,500 to 41,000 years ago in what’s now the area around Ranis, Germany. The Ranis population, based on how their genomes compare to other ancient and modern people, seem to have been part of one of the first groups to split off from the wave of humans who migrated out of Africa, through the Levant, and into Eurasia sometime around 50,000 years ago. They carried with them traces of what their ancestors had gotten up to during that journey: about 2.9 percent of their genomes were made up of segments of Neanderthal ancestry.

Based on how long the Ranis people’s segments of Neanderthal DNA were (longer chunks of Neanderthal ancestry tend to point to more recent mixing), the interspecies mingling happened about 80 generations, or about 2,300 years, before the Ranis people lived and died. That’s about 49,000 to 45,000 years ago. The dates from both studies line up well with each other and with archaeological evidence that points to when Neanderthal and Homo sapiens cultures overlapped in parts of Europe and Asia.

What’s still not clear is whether that period of contact lasted the full 5,000 to 7,000 years, or if, as Johannes Krause (also of the Max Planck Institute) suggests, it was only a few centuries—1,500 years at the most—that fell somewhere within that range of dates.

Natural selection worked fast on our borrowed Neanderthal DNA

Once those first Homo sapiens in Eurasia had acquired their souvenir Neanderthal genes (forget stealing a partner’s hoodie; just take some useful segments of their genome), natural selection got to work on them very quickly, discarding some and passing along others, so that by about 100 generations after the “event,” the pattern of Neanderthal DNA segments in people’s genomes looked a lot like it does today.

Iasi and his colleagues looked through their catalog of genomes for sections that contained more (or less) Neanderthal ancestry than you’d expect to find by random chance—a pattern that suggests that natural selection has been at work on those segments. Some of the segments that tended to include more Neanderthal gene variants included areas related to skin pigmentation, the immune response, and metabolism. And that makes perfect sense, according to Iasi.

“Neanderthals had lived in Europe, or outside of Africa, for thousands of years already, so they were probably adapted to their environment, climate, and pathogens,” said Iasi during the press conference. Homo sapiens were facing selective pressure to adapt to the same challenges, so genes that gave them an advantage would have been more likely to get passed along, while unhelpful ones would have been quick to get weeded out.

The most interesting questions remain unanswered

The Neanderthal DNA that many people carry today, the researchers argue, is a legacy from just 100 or 200 Neanderthals.

“The effective population size of modern humans outside Africa was about 5,000,” said Krause in the press conference. “And we have a ratio of about 50 to 1 in terms of admixture [meaning that Neanderthal segments account for about 2 percent of modern genomes in people who aren’t of African ancestry], so we have to say it was about 100 to maybe 200 Neanderthals roughly that mixed into the population.” Assuming Krause is right about that and about how long the two species stayed in contact, a Homo sapiens/Neanderthal pairing would have happened every few years.

So we know that Neanderthals and members of our species lived in close proximity and occasionally produced children for at least several centuries, but no artifacts, bones, or ancient DNA have yet revealed much of what that time, or that relationship, was actually like for either group of people.

The snippets of Neanderthal ancestry left in many modern genomes, and those of people who lived tens of thousands of years ago, don’t offer any hints about whether that handful of Neanderthal ancestors were mostly male or mostly female, which is something that could shed light on the cultural rules around such pairings. And nothing archaeologists have unearthed so far can tell us whether those pairings were consensual, whether they were long-term relationships or hasty flings, or whether they involved social relationships recognized by one (or both) groups. We may never have answers to those questions.

And where did it all happen? Archaeologists haven’t yet found a cave wall inscribed with “Og heart Grag,” but based on the timing, Neanderthals and Homo sapiens probably met and lived alongside each other for at least a few centuries, somewhere in “the Near East,” which includes parts of North Africa, the Levant, what’s now Turkey, and what was once Mesopotamia. That’s one of the key routes that people would have followed as they migrated from Africa into Europe and Asia, and the timing lines up with when we know that both Homo sapiens and Neanderthals were in the area.

“This [same] genetic admixture also appears in East Asia and Australia and the Americas and Europe,” said Krause. “If it would have happened in Europe or somewhere else, then the distribution would probably look different than what we see.”

Science, 2023 DOI: 10.1126/science.adq3010;

Nature, 2023 DOI: 10.1038/s41586-024-08420-x;

(About DOIs ).

Kiona is a freelance science journalist and resident archaeology nerd at Ars Technica.

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NASA believes it understands why Ingenuity crashed on Mars

ingenuity, Mars, Science, Space / Rejus Almole / December 11, 2024

Eleven months after the Ingenuity helicopter made its final flight on Mars, engineers and scientists at NASA and a private company that helped build the flying vehicle said they have identified what probably caused it to crash on the surface of Mars.

In short, the helicopter’s on-board navigation sensors were unable to discern enough features in the relatively smooth surface of Mars to determine its position, so when it touched down, it did so moving horizontally. This caused the vehicle to tumble, snapping off all four of the helicopter’s blades.

Delving into the root cause

It is not easy to conduct a forensic analysis like this on Mars, which is typically about 100 million miles from Earth. Ingenuity carried no black box on board, so investigators have had to piece together their findings from limited data and imagery.

“While multiple scenarios are viable with the available data, we have one we believe is most likely: Lack of surface texture gave the navigation system too little information to work with,” said Ingenuity’s first pilot, Håvard Grip of NASA’s Jet Propulsion Laboratory, in a news release.

A team from NASA and a company that specializes in unmanned aerial vehicles, AeroVironment, started by looking at the terrain where Ingenuity was operating over during its 72nd flight, on January 18 of this year. The helicopter’s navigation system tracked visual features on the surface using a downward-looking camera. During its initial flights, Ingenuity was able to discern pebbles and other features to determine its position. But nearly three years later, Ingenuity was flying in a region of Jezero Crater filled with steep, relatively featureless sand ripples.

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