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Today — 21 November 2024Science – Ars Technica

NASA is stacking the Artemis II rocket, implying a simple heat shield fix

21 November 2024 at 17:50

The Space Launch System rocket that will dispatch four astronauts on the first Moon mission in more than 50 years passed a major milestone Wednesday.

NASA said ground teams inside the Vehicle Assembly Building (VAB) at Kennedy Space Center in Florida lifted the aft assembly of the rocket's left booster onto the mobile launch platform. Using an overhead crane, teams hoisted the left aft booster assembly—already filled with pre-packed solid propellant—from the VAB transfer aisle, over a catwalk dozens of stories high and then down onto mounting posts on the mobile launcher.

This marks the start of stacking for the second SLS rocket earmarked to launch NASA's Artemis II mission and slated to send NASA astronauts Reid Wiseman, Victor Glover, Christina Koch, and Canadian astronaut Jeremy Hansen on a 10-day flight around the far side of the Moon. Artemis II will be the first crewed flight of NASA's Artemis program and the first time people fly on the SLS rocket and Orion spacecraft.

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Study: Yes, tapping on frescoes can reveal defects

21 November 2024 at 16:25

The US Capitol building in Washington, DC, is adorned with multiple lavish murals created in the 19th century by Italian artist Constantino Brumidi. These include panels in the Senate first-floor corridors, Room H-144, and the rotunda. The crowning glory is The Apotheosis of Washington on the dome of the rotunda, 180 feet above the floor.

Brumidi worked in various mediums, including frescoes. Among the issues facing conservators charged with maintaining the Capitol building frescoes is delamination. Artists apply dry pigments to wet plaster to create a fresco, and a good fresco can last for centuries. Over time, though, the decorative plaster layers can separate from the underlying masonry, introducing air gaps. Knowing precisely where such delaminated areas are, and their exact shape, is crucial to conservation efforts, yet the damage might not be obvious to the naked eye.

Acoustician Nicholas Gangemi is part of a research group led by Joseph Vignola at the Catholic University of America that has been using laser Doppler vibrometry to pinpoint delaminated areas of the Capitol building frescoes. It's a non-invasive method that zaps the frescoes with sound waves and measures the vibrational signatures that reflect back to learn about the structural conditions. This in turn enables conservators to make very precise repairs to preserve the frescoes for future generations.

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Horrifying medical device malfunction: Abdominal implant erupts from leg

By: Beth Mole
21 November 2024 at 12:30

On May 7, 2011, Georgia resident Tonya Brand noticed a pain on the inside of her right thigh. As the pain grew worse in the 4- to 5-inch area of her leg, she headed to a hospital. There, doctors suspected she had a blood clot. But an ultrasound the next day failed to find one. Instead, it revealed a mysterious toothpick-sized object lodged in Brand's leg.

Over the next few weeks, the painful area became a bulge, and on June 17, Brand put pressure on it. Unexpectedly, the protrusion popped, and a 1.5-inch metal wire came poking out of her leg, piercing her skin.

The piece of metal was later determined to be part of a metal filter she had implanted in a vein in her abdomen more than two years earlier, in March 2009, according to a lawsuit Brand filed. The filter was initially placed in her inferior vena cava (IVC), the body's largest vein tasked with bringing deoxygenated blood from the lower body back up to the heart. The filter is intended to catch blood clots, preventing them from getting into the lungs, where they could cause a life-threatening pulmonary embolism. Brand got the IVC filter ahead of a spinal surgery she had in 2009, which could boost her risk of clots.

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Yesterday — 20 November 2024Science – Ars Technica

Qubit that makes most errors obvious now available to customers

20 November 2024 at 20:58

We're nearing the end of the year, and there are typically a flood of announcements regarding quantum computers around now, in part because some companies want to live up to promised schedules. Most of these involve evolutionary improvements on previous generations of hardware. But this year, we have something new: the first company to market with a new qubit technology.

The technology is called a dual-rail qubit, and it is intended to make the most common form of error trivially easy to detect in hardware, thus making error correction far more efficient. And, while tech giant Amazon has been experimenting with them, a startup called Quantum Circuits is the first to give the public access to dual-rail qubits via a cloud service.

While the tech is interesting on its own, it also provides us with a window into how the field as a whole is thinking about getting error-corrected quantum computing to work.

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Study: Why Aztec “death whistles” sound like human screams

20 November 2024 at 19:37

Archaeologists have discovered numerous ceramic or clay whistles at Aztec sites, dubbed "death whistles" because of their distinctive skull shapes. A new paper published in the journal Communications Psychology examines the acoustical elements of the unique shrieking sounds produced by those whistles, as well as how human listeners are emotionally affected by the sounds. The findings support the hypothesis that such whistles may have been used in Aztec religious rituals or perhaps as mythological symbols.

Archaeologists unearthed the first Aztec death whistles, also known as ehecachichtlis, in 1999 while excavating the Tlatelolco site in Mexico City. They found the body of a sacrificial victim, a 20-year-old male who had been beheaded, at the base of the main stairway of a temple dedicated to the wind god Ehecatl. The skeleton was clutching two ceramic skull-shaped whistles, one in each hand, along with other artifacts. More skull whistles were subsequently found, and they've found their way into popular culture. For instance, in Ghostbusters: Afterlife (2021), Egon Spengler had such a whistle in his secret laboratory collection.

Scholars have puzzled over the purpose of the skull whistles, although given the dearth of concrete evidence, most suggestions are highly speculative. One hypothesis is that it was used in battle, with hundreds of warriors blowing their whistles simultaneously as a battle cry. Music archaeologist Arnd Adje Both has dismissed that idea, suggesting instead that the whistle's purpose was more likely tied to ceremonial or religious practices, like human sacrifice. Yet another hypothesis proposes that the whistles were intended as symbols of a deity. The skull shape, for instance, might allude to the Aztec god of the underworld, Mictlantecuhtli.

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SpaceX just got exactly what it wanted from the FAA for Texas Starship launches

20 November 2024 at 17:52

A day after SpaceX launched its Starship rocket for the sixth time, the company received good news from the Federal Aviation Administration regarding future launch operations from its Starbase facility in South Texas.

In a draft version of what is known as an "Environmental Assessment," the FAA indicated that it will grant SpaceX permission to increase the number of Starship launches in South Texas to 25 per year from the current limit of five. Additionally, the company will likely be allowed to continue increasing the size and power of the Super Heavy booster stage and Starship upper stage.

"FAA has concluded that the modification of SpaceX’s existing vehicle operator license for Starship/Super Heavy operations conforms to the prior environmental documentation, consistent with the data contained in the 2022 PEA, that there are no significant environmental changes, and all pertinent conditions and requirements of the prior approval have been met or will be met in the current action," the federal agency stated in its conclusion.

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Cracking the recipe for perfect plant-based eggs

An egg is an amazing thing, culinarily speaking: delicious, nutritious, and versatile. Americans eat nearly 100 billion of them every year, almost 300 per person. But eggs, while greener than other animal food sources, have a bigger environmental footprint than almost any plant food—and industrial egg production raises significant animal welfare issues.

So food scientists, and a few companies, are trying hard to come up with ever-better plant-based egg substitutes. “We’re trying to reverse-engineer an egg,” says David Julian McClements, a food scientist at the University of Massachusetts Amherst.

That’s not easy, because real eggs play so many roles in the kitchen. You can use beaten eggs to bind breadcrumbs in a coating, or to hold together meatballs; you can use them to emulsify oil and water into mayonnaise, scramble them into an omelet or whip them to loft a meringue or angel food cake. An all-purpose egg substitute must do all those things acceptably well, while also yielding the familiar texture and—perhaps—flavor of real eggs.

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The key moment came 38 minutes after Starship roared off the launch pad

20 November 2024 at 04:57

SpaceX launched its sixth Starship rocket Tuesday, proving for the first time that the stainless steel ship can maneuver in space and paving the way for an even larger, upgraded vehicle slated to debut on the next test flight.

The only hiccup was an abortive attempt to catch the rocket's Super Heavy booster back at the launch site in South Texas, something SpaceX achieved on the previous flight on October 13. The Starship upper stage flew halfway around the world, reaching an altitude of 118 miles (190 kilometers) before plunging through the atmosphere for a pinpoint slow-speed splashdown in the Indian Ocean.

The sixth flight of the world's largest launcher—standing 398 feet (121.3 meters) tall—began with a lumbering liftoff from SpaceX's Starbase facility near the US-Mexico border at 4 pm CST (22:00 UTC) Tuesday. The rocket headed east over the Gulf of Mexico, propelled by 33 Raptor engines clustered on the bottom of its Super Heavy first stage.

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Before yesterdayScience – Ars Technica

Microsoft and Atom Computing combine for quantum error correction demo

19 November 2024 at 21:00

In September, Microsoft made an unusual combination of announcements. It demonstrated progress with quantum error correction, something that will be needed for the technology to move much beyond the interesting demo phase, using hardware from a quantum computing startup called Quantinuum. At the same time, however, the company also announced that it was forming a partnership with a different startup, Atom Computing, which uses a different technology to make qubits available for computations.

Given that, it was probably inevitable that the folks in Redmond, Washington, would want to show that similar error correction techniques would also work with Atom Computing's hardware. It didn't take long, as the two companies are releasing a draft manuscript describing their work on error correction today. The paper serves as both a good summary of where things currently stand in the world of error correction, as well as a good look at some of the distinct features of computation using neutral atoms.

Atoms and errors

While we have various technologies that provide a way of storing and manipulating bits of quantum information, none of them can be operated error-free. At present, errors make it difficult to perform even the simplest computations that are clearly beyond the capabilities of classical computers. More sophisticated algorithms would inevitably encounter an error before they could be completed, a situation that would remain true even if we could somehow improve the hardware error rates of qubits by a factor of 1,000—something we're unlikely to ever be able to do.

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Scientist behind superconductivity claims ousted

19 November 2024 at 17:46

University of Rochester physicist Ranga Dias made headlines with his controversial claims of high-temperature superconductivity—and made headlines again when the two papers reporting the breakthroughs were later retracted under suspicion of scientific misconduct, although Dias denied any wrongdoing. The university conducted a formal investigation over the past year and has now terminated Dias' employment, The Wall Street Journal reported.

“In the past year, the university completed a fair and thorough investigation—conducted by a panel of nationally and internationally known physicists—into data reliability concerns within several retracted papers in which Dias served as a senior and corresponding author,” a spokesperson for the University of Rochester said in a statement to the WSJ, confirming his termination. “The final report concluded that he engaged in research misconduct while a faculty member here.”

The spokesperson declined to elaborate further on the details of his departure, and Dias did not respond to the WSJ's request for comment. Dias did not have tenure, so the final decision rested with the Board of Trustees after a recommendation from university President Sarah Mangelsdorf. Mangelsdorf had called for terminating his position in an August letter to the chair and vice chair of the Board of Trustees, so the decision should not come as a surprise. Dias' lawsuit claiming that the investigation was biased was dismissed by a judge in April.

Ars has been following this story ever since Dias first burst onto the scene with reports of a high-pressure, room-temperature superconductor, published in Nature in 2020. Even as that paper was being retracted due to concerns about the validity of some of its data, Dias published a second paper in Nature claiming a similar breakthrough: a superconductor that works at high temperatures but somewhat lower pressures. Shortly afterward, that paper was retracted as well. As Ars Science Editor John Timmer reported previously:

Dias' lab was focused on high-pressure superconductivity. At extreme pressures, the orbitals where electrons hang out get distorted, which can alter the chemistry and electronic properties of materials. This can mean the formation of chemical compounds that don't exist at normal pressures, along with distinct conductivity. In a number of cases, these changes enabled superconductivity at unusually high temperatures, although still well below the freezing point of water.

Dias, however, supposedly found a combination of chemicals that would boost the transition to superconductivity to near room temperature, although only at extreme pressures. While the results were plausible, the details regarding how some of the data was processed to produce one of the paper's key graphs were lacking, and Dias didn't provide a clear explanation.

The ensuing investigation cleared Dias of misconduct for that first paper. Then came the second paper, which reported another high-temperature superconductor forming at less extreme pressures. However, potential problems soon became apparent, with many of the authors calling for its retraction, although Dias did not.

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Novo Nordisk sells hit weight-loss drug in China—at fraction of US price

By: Beth Mole
19 November 2024 at 17:10

Patients in China will be able to purchase the blockbuster weight-loss drug Wegovy for 1,400 yuan, or about $193, just a fraction of the US list price of $1,349, according to media reports.

The price in China is in line with pricing elsewhere outside of the US. As Sen. Bernie Sanders (I-Vt.) noted in a September Senate hearing, Wegovy, made by Novo Nordisk, is sold for $265 in Canada, $186 in Denmark, $137 in Germany, and just $92 in the United Kingdom. In the hearing, Sanders and other senators grilled Novo Nordisk CEO Lars Jørgensen on the "outrageously high prices" in the US of Wegovy and the company's other popular GLP-1 drug, Ozempic, used for diabetes.

"What we are dealing with today is not just an issue of economics, it is not just an issue of corporate greed. It is a profound moral issue," Sanders said in opening remarks about the prices of the highly effective drugs.

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SpaceX will try some new tricks on Starship’s sixth test flight

19 November 2024 at 15:56

The sixth flight of SpaceX's giant Starship rocket, set for takeoff on Tuesday from South Texas, will test the vehicle's limits in new ways.

Most importantly, SpaceX will attempt to briefly reignite one of Starship's six Raptor engines in space. SpaceX tried this on Starship's third launch in March but aborted the engine restart after the rocket lost roll control during the flight's coast phase.

A successful engine relight demonstration would pave the way for future Starships to ascend into stable, sustainable orbits. It's essential to test the Raptor engine's ability to reignite in space for a deorbit burn to steer Starship out of orbit toward an atmospheric reentry.

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Emergent gravity may be a dead idea, but it’s not a bad one

19 November 2024 at 15:19

Emergent gravity is a bold idea.

It claims that the force of gravity is a mere illusion, more akin to friction or heat—a property that emerges from some deeper physical interaction. This emergent gravity idea might hold the key to rewriting one of the fundamental forces of nature—and it could explain the mysterious nature of dark matter.

But in the years since its original proposal, it has not held up well to either experiment or further theoretical inquiry. Emergent gravity may not be a right answer. But it is a clever one, and it's still worth considering, as it may hold the seeds of a greater understanding.

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Can going to a haunted house boost the immune system?

19 November 2024 at 13:55

Spooky season has come and gone, but those Halloween revelers who took in a haunted house during the season might just have boosted their immune systems by doing so, according to a new paper published in the journal Brain, Behavior, and Immunity.

As previously reported, fear is typically viewed as a negative emotion, an adverse reaction to keep us on our toes with regard to potential dangers in our environment. But human beings also tend to seek out scary movies, horror novels, or haunted houses—and not just during the Halloween season. This tendency has been dubbed "recreational fear" in the academic literature: a "mixed emotional experience of fear and enjoyment."

Co-author Mathias Clasen of Aarhus University, author of Why Horror Seduces, specializes in studying recreational fear and and co-directs the Recreational Fear Lab with cognitive scientist Marc Andersen. For instance, Clasen and his colleagues have examined the dominant personality traits of horror fans. (They tend to score high on openness to experience, also called intellect imagination.) In 2019 we reported on his investigation of two different fear-regulation strategies employed by subjects participating in a Danish haunted house: "adrenaline junkies," who lean into the fear, and "white-knucklers," who try to tamp down their fear.

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The ISS has been leaking air for 5 years, and engineers still don’t know why

18 November 2024 at 22:19

Officials from NASA and Russia’s space agency don’t see eye to eye on the causes and risks of small but persistent air leaks on the International Space Station.

That was the word from the new chair of NASA's International Space Station Advisory Committee last week. The air leaks are located in the transfer tunnel of the space station's Russian Zvezda service module, one of the oldest elements of the complex.

US and Russian officials "don't have a common understanding of what the likely root cause is, or the severity of the consequences of these leaks," said Bob Cabana, a retired NASA astronaut who took the helm of the advisory committee earlier this year. Cabana replaced former Apollo astronaut Tom Stafford, who chaired the committee before he died in March.

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Trust in scientists hasn’t recovered from COVID. Some humility could help.

By: Beth Mole
18 November 2024 at 21:52

Scientists could win back trust lost during the COVID-19 pandemic if they just showed a little intellectual humility, according to a study published Monday in Nature Human Behavior.

It's no secret that scientists—and the science generally—took a hit during the health crisis. Public confidence in scientists fell from 87 percent in April 2000 to a low of 73 percent in October 2023, according to survey data from the Pew Research Center. And the latest Pew data released last week suggests it will be an uphill battle to regain what was lost, with confidence in scientists only rebounding three percentage points, to 76 percent in a poll from October.

Building trust

The new study in Nature Human Behavior may guide the way forward, though. The study encompasses five smaller studies probing the perceptions of scientists' trustworthiness, which previous research has linked to willingness to follow research-based recommendations.

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To invent the wheel, did people first have to invent the spindle?

18 November 2024 at 20:04

Twelve-thousand years ago, people in a coastal village in the Levant used stone weights on their spindles to spin thread faster and more evenly—and, some archeologists are arguing, in the process they pioneered the basic mechanics that eventually made cart wheels possible.

Archaeologists found hundreds of perforated, roundish, flattish pebbles in the 12,000-year-old village of Nahal Ein-Gev II, all with neat holes drilled in their centers. Based on their uneven appearance and their varied sizes, it seemed that these weren’t beads, but spindle whorls: a flywheel-like piece that makes a drop spindle spin faster and more steadily. The find is the oldest known evidence of a newfangled textile production technology called the drop spindle. But it may also have been a distant precursor to the wheel. According to archaeologists Talia Yashuv and Leore Grosman of the Hebrew University of Jerusalem, drop spindles work on the same mechanical principle as the earliest wheels, which show up on carts around 6,000 years ago during the Bronze Age.

“Circular objects with a hollowed center connected to a bar make one of the most important inventions of all time,” write Yashuv and Grosman in their recent paper. “At the core of it all, the importance of the wheel and axle lies in a relatively simple rotational mechanism capable of transforming linear to rotary motion and vice versa.”

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The amorous adventures of earwigs

Few people are fond of earwigs, with their menacing abdominal pincers—whether they’re skittering across your floor, getting comfy in the folds of your camping tent, or minding their own business.

Scientists, too, have given them short shrift compared with the seemingly endless attention they have lavished on social insects like ants and bees.

Yet, there are a handful of exceptions. Some researchers have made conscious career decisions to dig into the hidden, underground world where earwigs reside, and have found the creatures to be surprisingly interesting and social, if still not exactly endearing.

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SpaceX president predicts rapid increase in Starship launch rate

18 November 2024 at 15:49

As SpaceX made its final preparations for the sixth launch of its Starship rocket, the company's chief operating officer and president spoke at a financial conference on Friday about various topics, including the future of the massive rocket and the Starlink satellite system.

The Starship launch system is about to reach a tipping point, Gwynne Shotwell said, as it moves from an experimental rocket toward operational missions.

"We just passed 400 launches on Falcon, and I would not be surprised if we fly 400 Starship launches in the next four years," Shotwell said at the Baron Investment Conference in New York City. "We want to fly it a lot."

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© Eric Berger

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