×
NASA

Navajo Nation President Asks NASA to Delay Moon Launch Over Possible Human Remains (knau.org) 203

"Navajo Nation President Buu Nygren has asked NASA to delay a scheduled launch to the Moon that could include cremated remains," reports Arizona Public Radio station KNAU: Nygren says he recently learned of the January 8 launch of the Vulcan Centaur carrying the Peregrine Mission One. The lander will carry some payloads from a company known to provide memorial services by shipping human cremated remains to the Moon. Nygren wants the launch delayed and the tribe consulted immediately. He noted the Moon is sacred to numerous Indigenous cultures and that depositing human remains on it is "tantamount to desecration."

NASA previously came under fire after the ashes of former geologist and planetary scientist Eugene Shoemaker were sent to the Moon in 1998. Then-Navajo Nation President Albert Hale said the action was a gross insensitivity to the beliefs of many Native Americans. NASA later apologized and promised to consult with tribes before authorizing any similar missions in the future.

Music

Could We Build a Concert Venue in Space? (washingtonpost.com) 75

What would happen if we built a concert venue in near-Earth orbit? A science policy journalist explores the question in the Washington Post: Forget U2 in the Las Vegas Sphere. Take me to a real concert in the round, where I can float 360 degrees around the stage, watching a guitarist shred from the perspective of a fly and inventing dance moves that Earth's gravity would forbid.

Before you dismiss this as a hallucination, consider that we're on the cusp of a new era of space travel. Engineer and space architect Ariel Ekblaw, founder of MIT's Space Exploration Initiative, says that within a decade, a trip off the planet could become as accessible as a first-class airline ticket — and that, in 15 or 20 years, we can expect space hotels in near-Earth orbit. She's betting on it, having founded a nonprofit to design spherical, modular habitats that can assemble themselves in space so as to be lightweight and compact at launch, much like the James Webb Space Telescope that NASA vaulted into deep space two years ago.

"The first era of space travel was about survival," she told me as I recently toured her lab. "We're transitioning now to build spaces that are friendlier and more welcoming so that people can thrive in space as opposed to just survive." There's no reason, Ekblaw said, that a concert hall can't be one of those structures.

The article ultimately calls this "an impulse for space travel I can get behind: curiosity about who we are and what more we can create when we reach beyond Earth. This is the realm of not just scientists and engineers but of all kinds of dreamers. It's a rendition of space exploration that can engage anyone to imagine what's possible."
Space

'Behold - the Best Space Images of 2023' (scientificamerican.com) 5

As the year comes to a close, "one constant, reliable source of awe and beauty is the sky over our head..." writes astronomer Phil Plait in Scientific America

"And every year we see new things, or old things in new ways, and I've been set the wonderful task of selecting my favorites and relaying them and their import to you." End-of-year lists, especially those displaying astronomical imagery, tend to be splashy and colorful. That's understandable, but what they sometimes miss are the more subtle photographs, those that hide momentous discoveries in minor visual details or offer fresh perspectives on familiar objects. They may not leap off the page, but they still have an impact. That's what I've kept in mind while sorting through this year's celestial treasure trove. This gallery is by no means complete, but it shows what I think are some of the most interesting astronomical portraits to have emerged in 2023.

No gallery such as this would be complete without something from the James Webb Space Telescope (JWST), our newest infrared eye on the sky. This monster observatory has already brought so many small revolutions to astronomy that picking one from the past year is no small task. Should it be a baby star throwing an immense tantrum or a massive old star shedding material at colossal rates before it inevitably explodes as a supernova? Or should it be a map of a mind-stomping 100,000 galaxies?

Well, how about something very, very different — such as the skeletal structure of a nearby galaxy's intricate web of dust [also displayed at the top of Scientiic American's article]...? [I]t has a beautiful spiral structure and shows the effects of a smaller galaxy colliding with it. In the phenomenally sharp and decidedly eerie false-color view from JWST's Mid-Infrared Instrument, we see countless clouds of cosmic dust in a skeletonlike pattern. Each of these clouds is made up of small grains of rocky and sooty carbon-based molecules expelled by dying stars...

Astronomers captured this image to better understand how stars are born in stellar nurseries and how they evolve over time.

Space

Is It Possible to Beam Solar Power From Outer Space? (cnn.com) 130

"[F]or years it was written off," writes CNN. " 'The economics were just way out,' said Martin Soltau, CEO of the UK-based company Space Solar.

"That may now be changing as the cost of launching satellites falls sharply, solar and robotics technology advances swiftly, and the need for abundant clean energy to replace planet-heating fossil fuels becomes more urgent." There's a "nexus of different technologies coming together right now just when we need it," said Craig Underwood, emeritus professor of spacecraft engineering at the University of Surrey in the U.K. The problem is, these technologies would need to be deployed at a scale unlike anything ever done before... "The big stumbling block has been simply the sheer cost of putting a power station into orbit." Over the last decade, that has begun to change as companies such as SpaceX and Blue Origin started developing reusable rockets. Today's launch costs at around $1,500 per kilogram are about 30 times less than in the Space Shuttle era of the early 1980s.

And while launching thousands of tons of material into space sounds like it would have a huge carbon footprint, space solar would likely have a footprint at least comparable to terrestrial solar per unit of energy, if not a smaller, because of its increased efficiency as sunlight is available nearly constantly, said Mamatha Maheshwarappa, payload systems lead at UK Space Agency. Some experts go further. Underwood said the carbon footprint of space-based solar would be around half that of a terrestrial solar farm producing the same power, even with the rocket launch...

There is still a huge gulf between concept and commercialization. We know how to build a satellite, and we know how to build a solar array, Maheshwarappa said. "What we don't know is how to build something this big in space..." Scientists also need to figure out how to use AI and robotics to construct and maintain these structures in space. "The enabling technologies are still in a very low technology readiness," Maheshwarappa said. Then there's regulating this new energy system, to ensure the satellites are built sustainably, there's no debris risk, and they have an end-of-life plan, as well as to determine where rectenna sites should be located. Public buy-in could be another huge obstacle, Maheshwarappa said. There can be an instinctive fear when it comes to beaming power from space.

But such fears are unfounded, according to some experts. The energy density at the center of the rectenna would be about a quarter of the midday sun. "It is no different than standing in front of a heat lamp," Hajimiri said.

The article argues that governments and companies around the world "believe there is huge promise in space-based solar to help meet burgeoning demand for abundant, clean energy and tackle the climate crisis." And they cite several specific examples:
  • In 2020 the U.S. Naval Research Lab launched a module on an orbital test vehicle, to test solar hardware in space conditions.
  • This year Caltech electrical engineering professor led a team that successfully launched a 30-centimeter prototype equipped with transmitters — and successfully beamed detectable energy down to earth.
  • The U.S. Air Force Research Lab plans to launch a small demonstrator in 2025.
  • Europe's its Solaris program aims to prove "the technical and political viability of space-based solar, in preparation for a possible decision in 2025 to launch a full development program."
  • One Chinese spacecraft designer and manufacturer hopes to send a solar satellite into low orbit in 2028 and high orbit by 2030, according to a 2022 South China Morning News report.

Science

Novel Helmet Liner 30 Times Better At Stopping Concussions (newatlas.com) 50

An anonymous reader quotes a report from New Atlas: Researchers have developed a new, lightweight foam made from carbon nanotubes that, when used as a helmet liner, absorbed the kinetic energy caused by an impact almost 30 times better than liners currently used in US military helmets. The foam could prevent or significantly reduce the likelihood of concussion in military personnel and sportspeople. Among sportspeople and military vets, traumatic brain injury (TBI) is one of the major causes of permanent disability and death. Injury statistics show that the majority of TBIs, of which concussion is a subtype, are associated with oblique impacts, which subject the brain to a combination of linear and rotational kinetic energy forces and cause shearing of the delicate brain tissue.

To improve their effectiveness, helmets worn by military personnel and sportspeople must employ a liner material that limits both. This is where researchers from the University of Wisconsin-Madison come in. Determined to prevent -- or lessen the effect of -- TBIs caused by knocks to the body and head, they've developed a new lightweight foam material for use as a helmet liner. For the current study, Thevamaran built upon his previous research into vertically aligned carbon nanotube (VACNT) foams -- carefully arranged layers of carbon cylinders one atom thick -- and their exceptional shock-absorbing capabilities. Current helmets attempt to reduce rotational motion by allowing a sliding motion between the wearer's head and the helmet during impact. However, the researchers say this movement doesn't dissipate energy in shear and can jam when severely compressed following a blow. Instead, their novel foam doesn't rely on sliding layers.

VACNT foam sidesteps this shortcoming via its unique deformation mechanism. Under compression, the VACNTs undergo collective sequentially progressive buckling, from increased compliance at low shear strain levels to a stiffening response at high strain levels. The formed compression buckles unfold completely, enabling the VACNT foam to accommodate large shear strains before returning to a near initial state when the load is removed. The researchers found that at 25% precompression, the foam exhibited almost 30 times higher energy dissipation in shear -- up to 50% shear strain -- than polyurethane-based elastomeric foams of similar density.
The study has been published in the journal Experimental Mechanics.
Space

SpaceX Wows With a Double Header of Final 2023 Rocket Launches (space.com) 43

SpaceX on Thursday launched two rockets into orbit, only three hours apart, bringing its total number of launches to 98 in 2023. Space.com reports: The first SpaceX mission to take to the skies Thursday (Dec. 28) was a Falcon Heavy rocket carrying the U.S. military's secretive X-37B space plane, designed mission USSF-52. That blasted off from NASA's Kennedy Space Center in Florida at 8:07 p.m. EST (0107 GMT on Dec. 29). This marked the second Falcon Heavy flight of 2023. Second up on the launch docket for Thursday, hours later, was a Falcon 9 liftoff carrying 23 SpaceX Starlink units to low Earth orbit from nearby Cape Canaveral Space Force Station. This launch took place at 11:01 p.m. EST (0401 GMT on Dec. 29). This was SpaceX's 98th and final launch of 2023, and the 96th flight for a Falcon 9 rocket this year.

SpaceX's 97th launch overall for this year marked the seventh flight for X-37B, but the first time the space plane hitched a lift atop a Falcon Heavy rocket. The X-37B/Falcon Heavy launch had been scrubbed several times previously due to bad weather and an issue with ground equipment. The launch of 23 Starlink broadband satellites from Space Launch Complex 40 (SLC-40) at Cape Canaveral Space Force Station in Florida that capped off 2023 was also the 96th launch of a Falcon 9 rocket during this year. SpaceX's next launch is targeted for Jan. 2, 2024 and will see a further 21 Starlink satellites lift to orbit to join the over 5,500 internet supplying units currently orbiting Earth.

Medicine

Chemicals of 'Concern' Found In Philips Breathing Machines (propublica.org) 43

In 2021, Philips pulled its popular sleep apnea machines and ventilators off the shelves after discovering that an industrial foam built into the devices to reduce noise could release toxic particles and fumes into the masks worn by patients. "But as Philips publicly pledged to send out replacements, supervisors inside the company's headquarters near Pittsburgh were quietly racing to manage a new crisis that threatened the massive recall and posed risks to patients all over again," reports ProPublica. "Tests by independent laboratories retained by Philips had found that a different foam used by the company -- material fitted inside the millions of replacement machines -- was also emitting dangerous chemicals, including formaldehyde, a known carcinogen."

"Though Philips has said the machines are safe, ProPublica and the Pittsburgh Post-Gazette obtained test results and other internal records that reveal for the first time how scientists working for the company grew increasingly alarmed and how infighting broke out as the new threat reached the highest levels of the Pittsburgh operation. The findings also underscore an unchecked pattern of corporate secrecy that began long before Philips decided to use the new foam." From the report: The company had previously failed to disclose complaints about the original foam in its profitable breathing machines, a polyester-based polyurethane material that was found to degrade in heat and humidity. Former patients and others have described hundreds of deaths and thousands of cases of cancer in government reports. After the introduction of the new foam in 2021, this one made of silicone, the company again held back details about the problem from the public even as it sent out replacement machines with the new material to customers around the world.

One of the devices was the DreamStation 2, a newly released continuous positive airway pressure, or CPAP, machine promoted as one of the company's primary replacements. Federal regulators were alerted to the concern more than two years ago but said in a news release at the time that the company was carrying out additional tests on the foam and that patients should keep using their replacements until more details were available. The Food and Drug Administration has not provided new information on the test results since then, and it is still unclear whether the material is safe. That leaves millions of people in the United States alone caught in the middle, including those with sleep apnea, which causes breathing to stop and start through the night and can lead to heart attacks, strokes and sudden death.

The new foam isn't the only problem: An internal investigation at Philips launched in the months after the recall found that water was condensing in the circuitry of the DreamStation 2, creating a new series of safety risks. "Loss of therapy, thermal events, and shock hazards," the investigation concluded. The FDA issued an alert about overheating last month, warning that the devices could produce "fire, smoke, burns, and other signs of overheating" and advising patients to keep the machines away from carpet, fabric and "other flammable materials." Philips has said that customers could continue using the devices if they followed safety instructions. ...

Patents

Scientists Still Shoot For the Moon With Patent-Free Covid Drug 11

An anonymous reader quotes a report from Bloomberg, written by Naomi Kresge: In the early days of the Covid-19 pandemic, hundreds of scientists from all over the world banded together in an open-source effort to develop an antiviral that would be available for all. They could never have anticipated the many roadblocks they would face along the way, including the Russian invasion of Ukraine, which made refugees out of a group of Kyiv chemists who were doing important work for the project. The group, which called itself Covid Moonshot, hasn't given up on its effort to introduce a more affordable, patent-free treatment for the virus. Their open-source Covid antiviral, now funded by Wellcome, is on track to be ready for human testing within the next year and a half, according to Annette von Delft, a University of Oxford scientist and one of the Moonshot group's leaders. More early discovery work on a range of potential inhibitors for other viruses is also still going on and being funded by a US government grant.

"It's a bit like a proof of concept," von Delft says, for bringing a patent-free experimental drug into the clinic, a model that could be repurposed as a tool to fight neglected tropical diseases or antimicrobial resistance, or prepare for future pandemics. "Can we come up with a strategic model that can help those kinds of compounds with less of a business case along?" Of course, there was definitely a business case for a Covid antiviral, and some of the biggest drugmakers rushed to develop them. In 2022, Pfizer Inc.'s Paxlovid was one of the world's best-selling medicines with $18.9 billion in revenue. Demand has since cratered for the pill, which needs to be given shortly after infection and can't be taken alongside a number of other commonly prescribed medicines. Analysts expect the Paxlovid revenue to plunge just shy of $1 billion this year.

However, there is still a need for a better Covid antiviral, particularly in countries where access to the Pfizer pill is limited, according to von Delft. Covid cases have surged again this holiday season, with the rise of a new variant called JN.1 reminding us that the virus is still changing to evade the immunity we've built up so far. Just before Christmas, UK authorities said about one in every 24 people in England and Scotland had the disease. An accessible antiviral could help people return to work more quickly, and it could also be tested as a potential treatment for long Covid. "We know from experience in viral disease that there will be resistance variants evolving over time," von Delft said. "We'll need more than one."
Piracy

Reckless DMCA Deindexing Pushes NASA's Artemis Towards Black Hole (torrentfreak.com) 83

Andy Maxwell reports via TorrentFreak: As the crew of Artemis 2 prepare to become the first humans to fly to the moon since 1972, the possibilities of space travel are once again igniting imaginations globally. More than 92% of internet users who want to learn more about this historic mission and the program in general are statistically likely to use Google search. Behind the scenes, however, the ability to find relevant content is under attack. Blundering DMCA takedown notices sent by a company calling itself DMCA Piracy Prevention Inc. claim to protect the rights of an OnlyFans/Instagram model working under the name 'Artemis'. Instead, keyword-based systems that fail to discriminate between copyright-infringing content and that referencing the word Artemis in any other context, are flooding towards Google. They contain demands to completely deindex non-infringing, unrelated content, produced by innocent third parties all over the world.

A recent deindexing demand dated December 13, 2022, lists DMCA Piracy Prevention Inc. of Canada as the sender. The name of the content owner is redacted but the notice itself states that the company represents a content creator performing under the name Artemis. The notice demands the removal of 3,617 URLs from Google search. If successful, those URLs would be completely unfindable by more than 92% of the world's population who use that search engine. [...] At least 9 of the first 20 URLs in the notice demand the removal of non-infringing articles and news reports referencing the Artemis space program. None have anything to do with the content the sender claims to protect. [...]

Theories as to who might own and/or operate DMCA Piracy Prevention Inc. aren't hard to find but the company does exist and is registered as a corporate entity in Canada. Registered at the same address is a company with remarkably similar details. BranditScan is a corporate entity operating in exactly the same market offering similar if not identical services. BranditScan has sent DMCA takedown notices to Google under three different notifier accounts.

United States

New US Immigration Rules Spur More Visa Approvals For STEM Workers (science.org) 102

Following policy adjustments by the U.S. Citizenship and Immigration Services (USCIS) in January, more foreign-born workers in science, technology, engineering, and math (STEM) fields are able to live and work permanently in the United States. "The jump comes after USCIS in January 2022 tweaked its guidance criteria relating to two visa categories available to STEM workers," reports Science Magazine. "One is the O-1A, a temporary visa for 'aliens of extraordinary ability' that often paves the way to a green card. The second, which bestows a green card on those with advanced STEM degrees, governs a subset of an EB-2 (employment-based) visa." From the report: The USCIS data, reported exclusively by ScienceInsider, show that the number of O-1A visas awarded in the first year of the revised guidance jumped by almost 30%, to 4570, and held steady in fiscal year 2023, which ended on 30 September. Similarly, the number of STEM EB-2 visas approved in 2022 after a "national interest" waiver shot up by 55% over 2021, to 70,240, and stayed at that level this year. "I'm seeing more aspiring and early-stage startup founders believe there's a way forward for them," says Silicon Valley immigration attorney Sophie Alcorn. She predicts the policy changes will result in "new technology startups that would not have otherwise been created."

President Joe Biden has long sought to make it easier for foreign-born STEM workers to remain in the country and use their talent to spur the U.S. economy. But under the terms of a 1990 law, only 140,000 employment-based green cards may be issued annually, and no more than 7% of those can go to citizens of any one country. The ceiling is well below the demand. And the country quotas have created decades-long queues for scientists and high-tech entrepreneurs born in India and China. The 2022 guidance doesn't alter those limits on employment-based green cards but clarifies the visa process for foreign-born scientists pending any significant changes to the 1990 law. The O-1A work visa, which can be renewed indefinitely, was designed to accelerate the path to a green card for foreign-born high-tech entrepreneurs.

Although there is no cap on the number of O-1A visas awarded, foreign-born scientists have largely ignored this option because it wasn't clear what metrics USCIS would use to assess their application. The 2022 guidance on O-1As removed that uncertainty by listing eight criteria -- including awards, peer-reviewed publications, and reviewing the work of other scientistsâ"and stipulating that applicants need to satisfy at least three of them. The second visa policy change affects those with advanced STEM degrees seeking the national interest waiver for an EB-2. Under the normal process of obtaining such a visa, the Department of Labor requires employers to first satisfy rules meant to protect U.S. workers from foreign competition, for example, by showing that the company has failed to find a qualified domestic worker and that the job will pay the prevailing wage. That time-consuming exercise can be waived if visa applicants can prove they are doing "exceptional" work of "substantial merit and national importance." But once again, the standard for determining whether the labor-force requirements can be waived was vague, so relatively few STEM workers chose that route. The 2022 USCIS guidance not only specifies criteria, which closely track those for the nonimmigrant, O-1A visa, but also allows scientists to sponsor themselves.

Science

Scientists Destroy 99% of Cancer Cells In the Lab Using Vibrating Molecules (sciencealert.com) 37

Scientists discovered a way to break apart the membranes of cancer cells by stimulating aminocyanine molecules with near-infrared light. Slashdot reader Baron_Yam shares a report from ScienceAlert: The research team from Rice University, Texas A&M University, and the University of Texas, says the new approach is a marked improvement over another kind of cancer-killing molecular machine previously developed, called Feringa-type motors, which could also break the structures of problematic cells. "It is a whole new generation of molecular machines that we call molecular jackhammers," says chemist James Tour from Rice University. "They are more than one million times faster in their mechanical motion than the former Feringa-type motors, and they can be activated with near-infrared light rather than visible light."

In tests on cultured, lab-grown cancer cells, the molecular jackhammer method scored a 99 percent hit rate at destroying the cells. The approach was also tested on mice with melanoma tumors, and half the animals became cancer-free. The structure and chemical properties of aminocyanine molecules mean they stay in sync with the right stimulus -- such as near-infrared light. When in motion, the electrons inside the molecules form what's known as plasmons, collectively vibrating entities that drive movement across the whole of the molecule. The plasmons have an arm on one side, helping to connect the molecules to the cancer cell membranes while the movements of the vibrations bash them apart. It's still early days for the research, but these initial findings are very promising.
The research has been published in Nature Chemistry.
Space

The First Secret Asteroid Mission Won't Be the Last (nytimes.com) 60

AstroForge, a private company, wants to mine a space rock, but it doesn't want the competition to find out which one. From a report: For generations, Western space missions have largely occurred out in the open. We knew where they were going, why they were going there and what they planned to do. But the world is on the verge of a new era in which private interests override such openness, with big money potentially on the line. Sometime in the coming year, a spacecraft from AstroForge, an American asteroid-mining firm, may be launched on a mission to a rocky object near Earth's orbit. If successful, it will be the first wholly commercial deep-space mission beyond the moon. AstroForge, however, is keeping its target asteroid secret.

The secret space-rock mission is the latest in an emerging trend that astronomers and other experts do not welcome: commercial space missions conducted covertly. Such missions highlight gaps in the regulation of spaceflight as well as concerns about whether exploring the cosmos will continue to benefit all humankind. "I'm very much not in favor of having stuff swirling around the inner solar system without anyone knowing where it is," said Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics in Massachusetts. "It seems like a bad precedent to set." But for AstroForge, the calculation is simple: If it reveals the destination, a competitor may grab the asteroid's valuable metals for itself. "Announcing which asteroid we are targeting opens up risk that another entity could seize that asteroid," said Matt Gialich, AstroForge's chief executive.

Earth

Top Scientists on the One Mystery on Earth They'd Like To Solve (theguardian.com) 64

From the depths of the Amazon rainforest to the deserts of Antarctica, huge questions remain unanswered about life on Earth. The Guardian asked leading scientists and conservationists: what is the one thing you would like to know about the planet that remains a mystery? TLDR, the questions/wishes are:1. How many species are there on Earth?
2. I'd go back 540m years to see the 'biological big bang'
3. Could some of the smallest life forms help avert climate crisis?
4. What is the full biodiversity of the Amazon or Congo basin rainforests?
5. How do animals influence the functioning of Earth?
6. What will happen to the Gulf Stream?
7. Do universal rules govern how plants and animals evolve?
8. How many humans could Earth support?
9. Which species will adapt to the climate crisis -- and which will not?

Science

The Negative Ramifications From Invitation Declines Are Less Severe Than We Think (arstechnica.com) 37

Abstract of a paper published on the American Psychological Association: People are frequently invited to join others for fun social activities. They may be invited to lunch, to attend a sporting event, to watch the season finale of a television show, and so forth. Invitees -- those who are on the receiving ends of invitations -- sometimes accept invitations from inviters -- those who extend invitations -- but other times, invitees decline. Unfortunately, saying no can be hard, leading invitees to accept invitations when they would rather not. The present work sheds light on one factor that makes it so hard to decline invitations.

We demonstrate that invitees overestimate the negative ramifications that arise in the eyes of inviters following an invitation decline. Invitees have exaggerated concerns about how much the decline will anger the inviter, signal that the invitee does not care about the inviter, make the inviter unlikely to offer another invitation in the future, and so forth. We also demonstrate that this asymmetry emerges in part because invitees exaggerate the degree to which inviters focus on the decline itself, as opposed to the thoughts ran through the invitee's head before deciding. Indeed, across multiple studies, we find support for this process through mediation and moderation, while simultaneously finding evidence against multiple alternative accounts. We conclude with a discussion of the contributions and limitations of this research, along with directions for future work.

Christmas Cheer

30 Years of Donald Knuth's 'Christmas Lectures' Are Online - Including 2023's (thenewstack.io) 29

"It's like visiting an old friend for the holidays," according to this article: Approaching his 86th birthday, Donald Knuth — Stanford's beloved computer science guru — honored what's become a long-standing tradition. He gave a December "Christmas lecture" that's also streamed online for all of his fans...

More than 60 years ago, back in 1962, a 24-year-old Donald Knuth first started writing The Art of Computer Programming — a comprehensive analysis of algorithms which, here in 2023, he's still trying to finish. And 30 years ago Knuth also began making rare live appearances each December in front of audiences of Stanford students...

Recently Stanford uploaded several decades of Knuth's past Christmas lectures, along with a series of 22 videos of Knuth from 1985 titled "the 'Aha' Sessions'" (courses in mathematical problem-solving). There are also two different sets of five videos from 1981 showing Knuth introducing his newly-created typesetting system TeX. There are even 12 videos from 1982 of what Knuth calls "an intensive course about the internal details."

And on Dec. 6, wearing his traditional brown holiday sweater, Knuth gave yet another live demonstration of the beautifully clear precision that's made him famous.

Science

Why the Dinosaurs Died (cnn.com) 52

"The age of the dinosaurs ended 66 million years ago when a city-size asteroid struck a shallow sea off the coast of what is now Mexico," writes CNN.

"But exactly how the mass extinction of 75% of the species on Earth unfolded in the years that followed the cataclysmic impact has remained unclear." Previous research suggested that sulfur released during the impact, which left the 112-mile-wide (180-kilometer-wide) Chicxulub crater, and soot from wildfires triggered a global winter, and temperatures plunged. However, a new study published Monday in the journal Nature Geoscience suggests that fine dust made from pulverized rock thrown up into Earth's atmosphere in the wake of the impact likely played a greater role. This dust blocked the sun to an extent that plants were unable to photosynthesize, a biological process critical for life, for almost two years afterward.

"Photosynthesis shutting down for almost two years after impact caused severe challenges (for life)," said lead study author and planetary scientist Cem Berk Senel, a postdoctoral researcher at the Royal Observatory of Belgium. "It collapsed the food web, creating a chain reaction of extinctions."

To reach their findings, scientists developed a new computer model to simulate the global climate after the asteroid strike. The model was based on published information on Earth's climate at that point in time, as well as new data from sediment samples taken from the Tanis fossil site in North Dakota that captured a 20-year period during the aftermath of the strike.

Earth

Livestock Surprise Scientists with Their Complex, Emotional Minds (science.org) 73

Slashdot reader sciencehabit writes: If you've ever seen a cow staring vacantly across a field, or a pig rolling around in its own filth, you might not think there's a lot going on in their head. You wouldn't be alone. People haven't given much credence to the intelligence of farm animals, and neither have scientists. But that's starting to change.

A growing field of research is showing that—when it comes to the minds of goats, cows, and other livestock—we may have been missing something big. Studies published over the past few years have shown that pigs show signs of empathy, goats rival dogs in some tests of social intelligence, and cows can be potty trained.

Much of this work is being carried out at the Research Institute for Farm Animal Biology (FBN) in Dummerstorf, Germany, one of the world's leading centers for investigating the minds of creatures that often end up on our dinner plate. From cows making friends to goats exhibiting signs of altruism, farm animals are upending popular—and scientific—conceptions of what's going on in their minds.

The work may not just rewrite our thinking about livestock, it might also change how we treat them. As Jan Langbein, an applied ethologist at FBN told says, 'If we don't understand how these animals think, then we won't understand what they need. And if we don't understand what they need, we can't design better environments for them.'

Math

World Modelling and 'The Personal, Political Art of Board-Game Design' (newyorker.com) 10

The New Yorker looks at 41-year-old Amabel Holland, an autistic board-game designer who "thinks about the world in terms of systems," and realized you could make a board game about almost anything, "and, when you did, its rules could both mirror and analyze the subject on which it was based."

They've since designed more than 60 games, and the article notes that Holland's work, "which is part of a larger turn toward complexity in the industry, often tackles historical and social subjects — death, religion, misinformation — using surprising 'mechanics,' or building blocks of game play, to immerse players in an experience." "With every game, you build a certain model of the world," Reiner Knizia, a former mathematician who's designed more than eight hundred games, told me. Several of his games illustrate market forces: in Modern Art, for instance, you play as auctioneers and buyers, hoping to buy low and sell high. Knizia is a traditional game designer inasmuch as he aims to "bring enjoyment to the people." But Amabel sometimes aims for the opposite of enjoyment... This Guilty Land, from 2018, is about the struggle to end slavery."
Holland says their games are "meant to evoke frustration" — specifically to communicate how difficult it can be to actually achieve political progress.

Thanks to Slashdot reader silverjacket for sharing the article.
Medicine

Vibrating Pill May Give Dieters a Feeling of Fullness, Study Suggests (theguardian.com) 56

Scientists have developed a vibrating pill that, when swallowed before eating, can create a feeling of fullness. The Guardian reports: The research, which has yet to be carried out in humans, shows that after 30 minutes of activity by the Vibes pill, pigs ate on average almost 40% less food in the following half hour than they did without the device, and gained weight more slowly. The Vibes name is an acronym derived from the pill's full title -- Vibrating Ingestible BioElectronic Stimulator. The work in pigs suggests the vibrations activate stretch receptors in the stomach, simulating the presence of food. This results in signals being sent to the hypothalamus in the brain via the vagus nerve, increasing levels of various hormones that give rise to a feeling of fullness and decreasing those that result in feelings of hunger.

"We envision the Vibes pill being ingested on a relatively empty stomach 20 to 30 min before anticipated meals to trigger the desired sensation of satiety early in the meal,â the team write, adding that when produced at scale, the cost of the pills is expected to be in the cents to one dollar range. The vibrations, which are powered by a battery encased in the swallowed capsule, can be triggered when stomach acid dissolves a membrane around the pill, or by a timer. The researchers say the pills, which are about the size of a large vitamin tablet, offer a non-invasive, temporary therapy, without the need for weight-loss surgery, and exit the body with other solid waste -- meaning in humans they are flushed down the toilet. However they suggest it could be possible to develop pills that are implanted, or stay in the stomach, to reduce the need for people to repeatedly take them, should they require continuing therapy.
Further reading: Man Reports PillCam Stuck In His Gut For Over 12 Weeks
Science

Psychologists Pinpoint Average Age Children Become Santa Sceptics (theguardian.com) 242

An anonymous reader quotes a report from The Guardian: From empty glasses of sherry on the mantelpiece to sooty footprints leading to the bedroom door, evidence of Santa's existence is clearly irrefutable. Yet most children will begin to question it at some point -- and many parents anticipate this moment with dread. Now psychologists have identified the average age when Santa skepticism creeps in, and which children are at greatest risk of harboring negative feelings when it does.

While most adults have fallen for the myth that Santa doesn't exist, many children still believe -- even if the idea of a single individual visiting the homes of billions of children in a single night is at odds with their wider reasoning skills. Dr Candice Mills, a psychologist at the University of Texas in Dallas, US, and a Santa sceptic, said: "Children typically begin to distinguish fantasy from reality during the preschool years, but their belief in the existence of a singular magical Santa Claus often continues into middle childhood." [...] To better understand this shift from belief to disbelief and children's experiences of it, Mills and her colleagues interviewed 48 six- to 15-year-olds who had stopped believing in Santa and 44 of their parents, plus a further 383 adults.

The research, which has not yet been peer reviewed, found that for most children, disbelief crept in gradually about the age of eight -- although some three- or four-year-olds had convinced themselves that Santa wasn't real, while other children believed in him until they were 15 or 16. In many cases, it was testimony from other disbelievers that finally crushed their faith. Mills said: "They may have had some skepticism based on logical reasoning -- like how can Santa Claus really get around the world in one night? -- but what pushes them over the edge is a classmate at school saying he's not real."

Slashdot Top Deals