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Today β€” 11 December 2024Science – Ars Technica

NASA believes it understands why Ingenuity crashed on Mars

11 December 2024 at 17:44

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.

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Β© NASA/JPL-Caltech/LANL/CNES/CNRS

New congressional report: β€œCOVID-19 most likely emerged from a laboratory”

11 December 2024 at 16:45

Recently, Congress' Select Subcommittee on the Coronavirus Pandemic released its final report. The basic gist is about what you'd expect from a Republican-run committee, in that it trashes a lot of Biden-era policies and state-level responses while praising a number of Trump's decisions. But what's perhaps most striking is how it tackles a variety of scientific topics, including many where there's a large, complicated body of evidence.

Notably, this includes conclusions about the origin of the pandemic, which the report describes as "most likely" emerging from a lab rather than being the product of the zoonotic transfer between an animal species and humans. The latter explanation is favored by many scientists.

The conclusions themselves aren't especially interesting; they're expected from a report with partisan aims. But the method used to reach those conclusions is often striking: The Republican majority engages in a process of systematically changing the standard of evidence needed for it to reach a conclusion. For a conclusion the report's authors favor, they'll happily accept evidence from computer models or arguments from an editorial in the popular press; for conclusions they disfavor, they demand double-blind controlled clinical trials.

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Β© Grace Cary

Yesterday β€” 10 December 2024Science – Ars Technica

In a not-so-subtle signal to regulators, Blue Origin says New Glenn is ready

10 December 2024 at 14:02

Blue Origin said Tuesday that the test payload for the first launch of its new rocket, New Glenn, is ready for liftoff. The company published an image of the "Blue Ring" pathfinder nestled up against one half of the rocket's payload fairing.

"There is a growing demand to quickly move and position equipment and infrastructure in multiple orbits," the company's chief executive, Dave Limp, said on LinkedIn. "Blue Ring has advanced propulsion and communication capabilities for government and commercial customers to handle these maneuvers precisely and efficiently."

This week's announcementβ€”historically Blue Origin has been tight-lipped about new products, but is opening up more as it nears the debut of its flagship New Glenn rocketβ€”appears to serve a couple of purposes.

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Β© Blue Origin

Before yesterdayScience – Ars Technica

Paleolithic deep-cave compound likely used for rituals

9 December 2024 at 20:00

Archaeologists excavating a paleolithic cave site in Galilee, Israel, have found evidence that a deep-cave compound at the site may have been used for ritualistic gatherings, according to a new paper published in the Proceedings of the National Academy of Sciences (PNAS). That evidence includes the presence of a symbolically carved boulder in a prominent placement, and well as the remains of what may have been torches used to light the interior. And the acoustics would have been conducive to communal gatherings.

Dating back to the Early Upper Paleolithic period, Manot Cave was found accidentally when a bulldozer broke open its roof during construction in 2008. Archaeologists soon swooped in and recovered such artifacts as stone tools, bits of charcoal, remains of various animals, and a nearly complete human skull.

The latter proved to be especially significant, as subsequent analysis showed that the skull (dubbed Manot 1) had both Neanderthal and modern features and was estimated to be about 54,700 years old. That lent support to the hypothesis that modern humans co-existed and possibly interbred with Neanderthals during a crucial transition period in the region, further bolstered by genome sequencing.

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Β© Assaf Peretz, Israel Antiquities Authority

Google gets an error-corrected quantum bit to be stable for an hour

9 December 2024 at 18:25

On Monday, Nature released a paper from Google's quantum computing team that provides a key demonstration of the potential of quantum error correction. Thanks to an improved processor, Google's team found that increasing the number of hardware qubits dedicated to an error-corrected logical qubit led to an exponential increase in performance. By the time the entire 105-qubit processor was dedicated to hosting a single error-corrected qubit, the system was stable for an average of an hour.

In fact, Google told Ars that errors on this single logical qubit were rare enough that it was difficult to study them. The work provides a significant validation that quantum error correction is likely to be capable of supporting the execution of complex algorithms that might require hours to execute.

A new fab

Google is making a number of announcements in association with the paper's release (an earlier version of the paper has been up on the arXiv since August). One of those is that the company is committed enough to its quantum computing efforts that it has built its own fabrication facility for its superconducting processors.

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Β© Google

Latest James Webb data hints at new physics in Universe’s expansion

9 December 2024 at 14:00

Physicists have been puzzling over conflicting observational results pertaining to the accelerating expansion rate of our Universeβ€”a major discovery recognized by the 2011 Nobel Prize in Physics. New observational data from the James Webb Space Telescope (JWST) has confirmed that prior measurements of distances between nearby stars and galaxies made by the Hubble Space Telescope are not in error, according to a new paper published in The Astrophysical Journal. That means the discrepancy between observation and our current theoretical model of the Universe is more likely to be due to new physics.

As previously reported, the Hubble Constant is a measure of the Universe's expansion expressed in units of kilometers per second per megaparsec (Mpc). So, each second, every megaparsec of the Universe expands by a certain number of kilometers. Another way to think of this is in terms of a relatively stationary object a megaparsec away: Each second, it gets a number of kilometers more distant.

How many kilometers? That's the problem here. There are basically three methods scientists use to measure the Hubble Constant: looking at nearby objects to see how fast they are moving, gravitational waves produced by colliding black holes or neutron stars, and measuring tiny deviations in the afterglow of the Big Bang known as the Cosmic Microwave Background (CMB). However, the various methods have come up with different values. For instance, tracking distant supernovae produced a value of 73 km/s Mpc, while measurements of the CMB using the Planck satellite produced a value of 67 km/s Mpc.

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Β© NASA/ESA/CSA/STScI/A. Riess (JHU)

After critics decry Orion heat shield decision, NASA reviewer says agency is correct

6 December 2024 at 22:29

Within hours of NASA announcing its decision to fly the Artemis II mission aboard an Orion spacecraft with an unmodified heat shield, critics assailed the space agency, saying it had made the wrong decision.

"Expediency won over safety and good materials science and engineering. Sad day for NASA," Ed Pope, an expert in advanced materials and heat shields, wrote on LinkedIn.

There is a lot riding on NASA's decision, as the Artemis II mission involves four astronauts and the space agency's first crewed mission into deep space in more than 50 years.

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Β© NASA/Amanda Stevenson

US to start nationwide testing for H5N1 flu virus in milk supply

6 December 2024 at 21:18

On Friday, the US Department of Agriculture (USDA) announced that it would begin a nationwide testing program for the presence of the H5N1 flu virus, also known as the bird flu. Testing will focus on pre-pasteurized milk at dairy processing facilities (pasteurization inactivates the virus), but the order that's launching the program will require anybody involved with milk production before then to provide samples to the USDA on request. That includes "any entity responsible for a dairy farm, bulk milk transporter, bulk milk transfer station, or dairy processing facility."

The ultimate goal is to identify individual herds where the virus is circulating and use the agency's existing powers to do contact tracing and restrict the movement of cattle, with the ultimate goal of eliminating the virus from US herds.

A bovine disease vector

At the time of publication, the CDC had identified 58 cases of humans infected by the H5N1 flu virus, over half of them in California. All but two have come about due to contact with agriculture, either cattle (35 cases) or poultry (21). The virus's genetic material has appeared in the milk supply and, although pasteurization should eliminate any intact infectious virus, raw milk is notable for not undergoing pasteurization, which has led to at least one recall when the virus made its way into raw milk. And we know the virus can spread to other species if they drink milk from infected cows.

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Β© Credit: mikedabell

Lizards and snakes are 35 million years older than we thought

6 December 2024 at 18:16

Lizards are ancient creatures. They were around before the dinosaurs and persisted long after dinosaurs went extinct. We’ve now found they are 35 million years older than we thought they were.

Cryptovaranoides microlanius was a tiny lizard that skittered around what is now southern England during the late Triassic, around 205 million years ago. It likely snapped up insects in its razor teeth (its name means β€œhidden lizard, small butcher”). But it wasn’t always considered a lizard. Previously, a group of researchers who studied the first fossil of the creature, or holotype, concluded that it was an archosaur, part of a group that includes the extinct dinosaurs and pterosaurs along with extant crocodilians and birds.

Now, another research team from the University of Bristol has analyzed that fossil and determined that Cryptovaranoides is not an archosaur but a lepidosaur, part of a larger order of reptiles that includes squamates, the reptile group that encompasses modern snakes and lizards. It is now also the oldest known squamate.

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Β© Lavinia Gandolfi/David Whiteside, Sophie Chambi-Trowell, Mike Benton and the Natural History Museum, London

Rocket Report: NASA delays Artemis again; SpinLaunch spins a little cash

6 December 2024 at 12:00

Welcome to Edition 7.22 of the Rocket Report! The big news is the Trump administration's announcement that commercial astronaut Jared Isaacman would be put forward as the nominee to serve as the next NASA Administrator. Isaacman has flown to space twice, and demonstrated that he takes spaceflight seriously. More background on Isaacman, and possible changes, can be found here.

As always, we welcome reader submissions, and 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.

Orbex pauses launch site work in Sutherland, Scotland. Small-launch vehicle developer Orbex will halt work on its own launch site in northern Scotland and instead use a rival facility in the Shetland Islands, Space News reports. Orbex announced December 4 that it would "pause" construction of Sutherland Spaceport in Scotland and instead use the SaxaVord Spaceport on the island of Unst in the Shetlands for its Prime launch vehicle. Orbex had been linked to Spaceport Sutherland since the UK Space Agency announced in 2018 it selected the site for a vertical launch complex.

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Β© SpaceX

Two European satellites launch on mission to blot out the Sunβ€”for science

6 December 2024 at 04:39

Two spacecraft developed by the European Space Agency launched on top of an Indian rocket Thursday, kicking off a mission to test novel formation flying technologies and observe a rarely seen slice of the Sun's ethereal corona.

ESA's Proba-3 mission is purely experimental. The satellites are loaded with sophisticated sensors and ranging instruments to allow the two spacecraft to orbit the Earth in lockstep with one another. Proba-3 will attempt to achieve millimeter-scale precision, several orders of magnitude better than the requirements for a spacecraft closing in for docking at the International Space Station.

"In a nutshell, it’s an experiment in space to demonstrate a new concept, a new technology that is technically challenging," said Damien Galano, Proba-3's project manager.

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Β© ESA - M. PΓ©doussaut / J. Versluys

New drone has legs for landing gear, enabling efficient launches

5 December 2024 at 23:34

Most drones on the market are rotary-wing quadcopters, which can conveniently land and take off almost anywhere. The problem is they are less energy-efficient than fixed-wing aircraft, which can fly greater distances and stay airborne for longer but need a runway, a dedicated launcher, or at least a good old-fashioned throw to get to the skies.

To get past this limit, a team of Swiss researchers at the Γ‰cole Polytechnique FΓ©dΓ©rale de Lausanne built a fixed-wing flying robot called RAVEN (Robotic Avian-inspired Vehicle for multiple ENvironments) with a peculiar bio-inspired landing gear: a pair of robotic bird-like legs. β€œThe RAVEN robot can walk, hop over obstacles, and do a jumping takeoff like real birds,” says Won Dong Shin, an engineer leading the project.

Smart investments

The key challenge in attaching legs to drones was that they significantly increased mass and complexity. State-of-the-art robotic legs were designed for robots walking on the ground and were too bulky and heavy to even think about using on a flying machine. So, Shin’s team started their work by taking a closer look at what the leg mass budget looked like in various species of birds.

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Β© EPFL/Alain Herzog

Study: Warming has accelerated due to the Earth absorbing more sunlight

5 December 2024 at 20:15

2023 was always going to be a hot year, given that warmer El NiΓ±o conditions were superimposed on the long-term trend of climate change driven by our greenhouse gas emissions. But it's not clear anybody was expecting the striking string of hot months that allowed the year to easily eclipse any previous year on record. As the warmth has continued at record levels even after the El NiΓ±o faded, it's an event that seems to demand an explanation.

On Thursday, a group of German scientistsβ€”Helge Goessling, Thomas Rackow, and Thomas Jungβ€”released a paper that attempts to provide one. They present data that suggests the Earth is absorbing more incoming sunlight than it has in the past, largely due to reduced cloud cover.

Balancing the numbers on radiation

Years with strong El NiΓ±o conditions tend to break records. But the 2023 El NiΓ±o was relatively mild. The effects of the phenomenon are also directly felt in the tropical Pacific, yet ocean temperatures set records in the Atlantic and contributed to a massive retreat in ice near Antarctica. So, there are clearly limits to what can be attributed to El NiΓ±o. Other influences that have been considered include the injection of water vapor into the stratosphere by the Hunga Tonga eruption, and a reduction in sulfur emissions due to new rules governing international shipping. 2023 also corresponds to a peak in the most recent solar cycle.

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Β© NASA

How did the CEO of an online payments firm become the nominee to lead NASA?

5 December 2024 at 19:14

President-elect Donald Trump announced Wednesday his intent to nominate entrepreneur and commercial astronaut Jared Isaacman as the next administrator of NASA.

For those unfamiliar with Isaacman, who at just 16 years old founded a payment processing company in his parents' basement that ultimately became a major player in online payments, it may seem an odd choice. However, those inside the space community welcomed the news, with figures across the political spectrum hailing Isaacman's nomination variously as "terrific," "ideal," and "inspiring."

This statement from Isaac Arthur, president of the National Space Society, is characteristic of the response: "Jared is a remarkable individual and a perfect pick for NASA Administrator. He brings a wealth of experience in entrepreneurial enterprise as well as unique knowledge in working with both NASA and SpaceX, a perfect combination as we enter a new era of increased cooperation between NASA and commercial spaceflight."

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Β© SpaceX

E-tattoos could make mobile EEGs a reality

5 December 2024 at 15:31
A 3D-printable EEG electrode e-tattoo. Credit: University of Texas at Austin.

Epidermal electronics attached to the skin via temporary tattoos (e-tattoos) have been around for more than a decade, but they have their limitations, most notably that they don't function well on curved and/or hairy surfaces. Scientists have now developed special conductive inks that can be printed right onto a person's scalp to measure brain waves, even if they have hair. According to a new paper published in the journal Cell Biomaterials, this could one day enable mobile EEG monitoring outside a clinical setting, among other potential applications.

EEGs are a well-established, non-invasive method for recording the electrical activity of the brain, a crucial diagnostic tool for monitoring such conditions as epilepsy, sleep disorders, and brain injuries. It's also an important tool in many aspects of neuroscience research, including the ongoing development of brain-computer interfaces (BCIs). But there are issues. Subjects must wear uncomfortable caps that aren't designed to handle the variation in people's' head shapes, so a clinician must painstakingly map out the electrode positions on a given patient's headβ€”a time-consuming process. And the gel used to apply the electrodes dries out and loses conductivity within a couple of hours, limiting how long one can make recordings.

By contrast, e-tattoos connect to skin without adhesives, are practically unnoticeable, and are typically attached via temporary tattoo, allowing electrical measurements (and other measurements, such as temperature and strain) using ultra-thin polymers with embedded circuit elements. They can measure heartbeats on the chest (ECG), muscle contractions in the leg (EMG), stress levels, and alpha waves through the forehead (EEG), for example.

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Β© University of Texas at Austin

Prenatal test accidentally picks up cancer in 50% of those with wonky results

By: Beth Mole
5 December 2024 at 12:18

In 2013, researchers reported an eye-opening case of a healthy pregnant woman with a puzzling prenatal test result. A routine genetic screen using cell-free DNAβ€”a highly accurate blood testβ€”suggested her fetus had an extra copy of chromosome 13 (Patau syndrome) and only one copy of chromosome 18. These results are devastating; both conditions can cause severe abnormalities. Those with Patau syndrome often only survive a few days or weeks after birth. But, when doctors looked at scans and did additional pregnancy testing, all they found was a healthy fetus developing normally. The woman carried on with her uncomplicated pregnancy and gave birth to a healthy baby.

The alarming genetic results may have been written off as a freak testing flub. But soon after giving birth, the otherwise healthy 37-year-old mother of two reported severe pelvic pain. Imaging revealed what looked like multiple bone tumors, and she was subsequently diagnosed with metastatic small cell carcinoma of vaginal origin. Tragically, she has since died.

Testing of one of her tumors found that the cancerous cells had an increased number of chromosome 13 relative to chromosome 18. Her prenatal test had picked up her deadly cancer.

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Β© Getty | NataliaDeriabina

These spiders listen for prey before hurling webs like slingshots

4 December 2024 at 23:00
A tethered mosquito approaches the web in the path of release of the cone, and triggers web release response. Credit: S.I. Han and T.A. Blackledge, 2024.

Ray spiders deploy an unusual strategy to capture prey in their webs. They essentially pull it back into a cone shape and release it when prey approaches, trapping said prey in the sticky silken threads. A few years ago, scientists noticed that they could get the spiders to release their webs just by snapping their fingers nearby, suggesting that the spiders relied at least in part on sound vibrations to know when to strike. Evidence for that hypothesis has now been confirmed in a new paper published in the Journal of Experimental Biology.

Most spider orb webs are static: the spiders weave them and fix them in place and then wait for prey to fly into the webs. That causes the silk threads to vibrate, alerting the spider that dinner is served. There are some species that actively actuate their webs, however, per the authors.

For instance, the triangle weaver spring-loads its triangular web once an insect has made contact so that the threads wrap around the prey in fractions of a second. Bolas spiders seem to detect prey in their vicinity through auditory cues, throwing a line of silk with a sticky end at passing moths to catch them. Ogre-faced spiders also seem to be able to hear potential prey, striking backward with a small silk net held in their front legs. It's a more proactive hunting strategy than merely waiting for prey to fly into a web.

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Β© S.I. Han and T.A. Blackledge, 2024

Dog domestication happened many times, but most didn’t pan out

4 December 2024 at 22:16

Between 8,000 and 12,000 years ago, people in Alaska kept reinventing dogs with mixed results.

The dogs that share our homes today are the descendants of a single group of wolves that lived in Siberia about 23,000 years ago. But for thousands of years after that split, the line between wolf and dog wasn’t quite clear-cut. A recent study shows that long after dogs had spread into Eurasia and the Americas, people living in what is now Alaska still spent time withβ€”and fedβ€”a bizarre mix of dogs, wolves, dog-wolf hybrids, and even some coyotes.

We just can’t stop feeding the wildlife

University of Arizona archaeologist FranΓ§ois LanoΓ« and his colleagues studied 111 sets of bones from dogs and wolves from archaeological sites across the Alaskan interior. The oldest bones came from wolves that roamed what’s now Alaska long before people set foot there, and the most recent came from modern, wild Alaskan wolves. In between, the researchers worked with the remains of both wolves and dogs (and even a couple of coyotes) that span a swath of time from about 1,000 to around 14,000 years ago. And it turns out that even the wolves were tangled up in the lives of nearby humans.

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Β© Russell Burden

Trump nominates Jared Isaacman to become the next NASA administrator

4 December 2024 at 18:41

President-elect Donald Trump announced Wednesday he has selected Jared Isaacman, a billionaire businessman and space enthusiast who twice flew to orbit with SpaceX, to become the next NASA administrator.

"I am delighted to nominate Jared Isaacman, an accomplished business leader, philanthropist, pilot, and astronaut, as Administrator of the National Aeronautics and Space Administration (NASA)," Trump posted on his social media platform, Truth Social. "Jared will drive NASA’s mission of discovery and inspiration, paving the way for groundbreaking achievements in space science, technology, and exploration."

In a post on X, Isaacman said he was "honored" to receive Trump's nomination.

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Β© Inspiration4 / John Kraus

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