Science – Page 19

New Kuiper Belt objects lurk farther away than we ever thought

astronomy, Kuiper belt, New Horizons, planetary science, Science / Rejus Almole / October 5, 2024

Our Solar System’s Kuiper Belt appears to be substantially larger than we thought.

Back in 2017, NASA graphics indicated that New Horizons would be at the outer edge of the Kuiper Belt by around 2020. That hasn’t turned out to be true. Credit: NASA

In the outer reaches of the Solar System, beyond the ice giant Neptune, lies a ring of comets and dwarf planets known as the Kuiper Belt. The closest of these objects are billions of kilometers away. There is, however, an outer limit to the Kuiper Belt. Right?

Until now, it was thought there was nothing beyond 48 AU (astronomical units) from the Sun, (one AU is slightly over 150 million km). It seemed there was little beyond that. That changed when NASA’s New Horizons team detected 11 new objects lurking from 60 to 80 AU. What was thought to be empty space turned out to be a gap between the first ring of Kuiper Belt objects and a new, second ring. Until now, it was thought that our Solar System is unusually small when compared to exosolar systems, but it evidently extends farther out than anyone imagined.

While these objects are only currently visible as pinpoints of light, and Fraser is allowing room for error until the spacecraft gets closer, what their existence could tell us about the Kuiper Belt and the possible origins of the Solar System is remarkable.

Living on the edge

The extreme distance of the new objects has put them in a class all their own. Whether they are similar to other Kuiper Belt objects in morphology and composition remains unknown since they are so faint. As New Horizons approaches them, observations are now simultaneously being made with its LORRI (Long Range Reconnaissance Imager) telescope and the Subaru Telescope, which might reveal that they actually do not belong to a different class in terms of composition.

“The reason we’re using Subaru is its Hyper Suprime-Cam, which has a really wide field of vision,” New Horizons researcher Wesley Fraser, who led the study, told Ars Technica (the results are soon to be published in the Planetary Science Journal). “The camera can go deep and wide quickly, and we stare down the pipe of LORRI, looking down that trajectory to find anything nearby.”

These objects are near the edge of the heliosphere of the Solar System, where it transitions to interstellar space. The heliosphere is formed by the outflow of charged particles, or solar wind, that creates something of a bubble around our Solar System; combined with the Sun’s magnetic field, this protects us from outside cosmic radiation.

The new objects are located where the strength of the Sun’s magnetic field starts to break down. They might even be far enough for their orbits to occasionally take them beyond the heliosphere, where they will be pummeled by intense cosmic radiation from the interstellar medium. This, combined with their solar wind exposure, might affect their composition, making it different from that of closer Kuiper Belt objects.

Even though it is impossible to know what these objects are like up close for now, how can we think of them? Fraser has an idea.

“If I had to guess, they are probably red and dark and devoid of water ice on the surface, which is quite common in the Kuiper Belt,” he said. “I think these objects will look a lot like the dwarf planet Sedna, but it’s possible they will look even more unusual.”

Many Kuiper Belt objects are a deep reddish color as a result of their organic chemicals being exposed to cosmic radiation. This breaks the hydrogen bonds in those chemicals, releasing much of the hydrogen into space and leaving behind an amorphous organic sludge that keeps getting redder the longer it is irradiated.

Fraser also predicts these objects are lacking in surface water ice because more distant Kuiper Belt objects (though not nearly as far-flung as the newly discovered ones) have not shown signs of it in observations. While water ice is common in the Kuiper Belt, he thinks these objects are probably hiding water ice underneath their red exterior.

Emerging from the dark

Investigating objects like this could change views on the origins of the Solar System and how it compares to the exosolar systems we have observed. Is our Solar System even normal?

Because the Kuiper Belt was thought to end at a distance of about 48 AU, the Solar System used to seem small compared to exosolar systems, where there are still objects floating around 150 AU from their star. The detection of objects at up to 80 AU from the Sun has put the Solar System in more of a normal range. It also seems to suggest that, since it is larger than we thought, that it also formed in a larger nebula.

“The timeline for Solar System formation is what we have to work out, and looking at the Kuiper Belt sets the stage for that very earliest moment, when gas and dust start to coalesce into macroscopic objects,” said New Horizons researcher Marc Buie. Buie discovered the object Arrokoth and led another study recently published in The Planetary Science Journal.

Arrokoth itself altered ideas about planet formation since its two lobes appear to have gently stuck together instead of crashing into each other in a violent collision, as some of our ideas had assumed. Nothing like it has ever been observed before or since.

Dust to dust

There is another potential thing that the New Horizons team is watching out for, and that is whether the new objects are binary.

About 10 to 15 percent of all known Kuiper Belt objects orbit partners in binary systems, and Fraser thinks binarity can reveal many things about the formation of planetesimals, solid objects that form in a young star system through gentle mergers with other objects that cause them to stick together. Some of these objects can become gravitationally bound to each other and form binaries.

As New Horizons travels farther, its dust counter, which sends back information about the velocity and mass of dust that hits it, shows that the amount of dust in its surroundings has not gone down. This dust comes from objects running into each other.

“It’s been finding that, as we go farther and farther out, the Solar System is getting dustier and dustier, which is exactly the opposite of what is expected at that distance,” New Horizons Principal Investigator Alan Stern told Ars Technica. “There might be a massive population of bodies colliding out there.”

NASA had previously decided that it was unlikely New Horizons would be able to pull off another Kuiper Belt object flyby like it did with Arrokoth, so the mission’s focus shifted to the heliosphere. Now that the New Horizons team has found unexpected objects this distant with the help of the Subaru Telescope, and dust keeps being detected as the spacecraft travels farther out, there might be an opportunity for another flyby. Stern is still cautious about the chances of that.

“We’re going to see how they compare to closer Kuiper Belt objects, but if we can find one we can get close to, we’ll get a chance to really compare their geology and their mode of origin,” Stern said. “But that’s a longshot because we’re running on a tenth of a tank of gas.”

The advantage of using Subaru combined with LORRI is that LORRI can be pointed sideways to see objects, or at least slightly past them, at right angles. This will be the dream team of telescopes if New Horizons can approach at least one of the new objects. If an object is behind the spacecraft, combining observations from different angles gives information about the physical surface of an object.

Using the Nancy Grace Roman Telescope could yield even more surprising observations in the future. It has a smaller mirror and a very wide field of view, Stern likens it to space binoculars, and it only has to be pointed at a target region once or twice (in comparison to hundreds of times for the James Webb Space Telescope) to search for and possibly discover objects in an extremely vast expanse of sky. Most other telescopes would have to be pointed thousands of times to do that.

“The desperate hope for all of us is that we will find more flyby targets,” Buie said. “If we could just get an object to register as a couple of pixels on LORRI, that would be incredible.”

Just a note to you on some stuff that’s going on in the background here. About a year ago, NASA decided that another KBO flyby was really unlikely, so they switched the mission focus to heliophysics (i.e., the edge of the heliosphere). Stern tried to fight that, and he has really looked to keep the focus on KBOs, which NASA now considers a “if we find one it can image, it will” situation. So I think a lot of his phrasing is in keeping with what he wants—more flybys. But it’s our job to give an accurate picture, which is that this event is unlikely.

Elizabeth Rayne is a creature who writes. Her work has appeared on SYFY WIRE, Space.com, Live Science, Grunge, Den of Geek, and Forbidden Futures. She lurks right outside New York City with her parrot, Lestat. When not writing, she is either shapeshifting, drawing, or cosplaying as a character nobody has ever heard of. Follow her on Threads and Instagram @quothravenrayne.

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Why trolls, extremists, and others spread conspiracy theories they don’t believe

conspiracy theories, misinformation, Policy, Science, syndication, trolling / Kris Guyer / October 5, 2024

Some just want to promote conflict, cause chaos, or even just get attention.

Picture of a person using an old Mac with a paper bag over his head. The bag has the face of a troll drawn on it.

There has been a lot of research on the types of people who believe conspiracy theories, and their reasons for doing so. But there’s a wrinkle: My colleagues and I have found that there are a number of people sharing conspiracies online who don’t believe their own content.

They are opportunists. These people share conspiracy theories to promote conflict, cause chaos, recruit and radicalize potential followers, make money, harass, or even just to get attention.

There are several types of this sort of conspiracy-spreader trying to influence you.

Coaxing conspiracists—the extremists

In our chapter of a new book on extremism and conspiracies, my colleagues and I discuss evidence that certain extremist groups intentionally use conspiracy theories to entice adherents. They are looking for a so-called “gateway conspiracy” that will lure someone into talking to them, and then be vulnerable to radicalization. They try out multiple conspiracies to see what sticks.

Research shows that people with positive feelings for extremist groups are significantly more likely to knowingly share false content online. For instance, the disinformation-monitoring company Blackbird.AI tracked over 119 million COVID-19 conspiracy posts from May 2020, when activists were protesting pandemic restrictions and lockdowns in the United States. Of these, over 32 million tweets were identified as high on their manipulation index. Those posted by various extremist groups were particularly likely to carry markers of insincerity. For instance, one group, the Boogaloo Bois, generated over 610,000 tweets, of which 58 percent were intent on incitement and radicalization.

You can also just take the word of the extremists themselves. When the Boogaloo Bois militia group showed up at the Jan. 6, 2021, insurrection, for example, members stated they didn’t actually endorse the stolen election conspiracy but were there to “mess with the federal government.” Aron McKillips, a Boogaloo member arrested in 2022 as part of an FBI sting, is another example of an opportunistic conspiracist. In his own words: “I don’t believe in anything. I’m only here for the violence.”

Combative conspiracists—the disinformants

Governments love conspiracy theories. The classic example of this is the 1903 document known as the “Protocols of the Elders of Zion,” in which Russia constructed an enduring myth about Jewish plans for world domination. More recently, China used artificial intelligence to construct a fake conspiracy theory about the August 2023 Maui wildfire.

Often the behavior of the conspiracists gives them away. Years later, Russia eventually confessed to lying about AIDS in the 1980s. But even before admitting to the campaign, its agents had forged documents to support the conspiracy. Forgeries aren’t created by accident. They knew they were lying.

As for other conspiracies it hawks, Russia is famous for taking both sides in any contentious issue, spreading lies online to foment conflict and polarization. People who actually believe in a conspiracy tend to stick to a side. Meanwhile, Russians knowingly deploy what one analyst has called a “fire hose of falsehoods.”

Likewise, while Chinese officials were spreading conspiracies about American roots of the coronavirus in 2020, China’s National Health Commission was circulating internal reports tracing the source to a pangolin.

Chaos conspiracists—the trolls

In general, research has found that individuals with what scholars call a high “need for chaos” are more likely to indiscriminately share conspiracies, regardless of belief. These are the everyday trolls who share false content for a variety of reasons, none of which are benevolent. Dark personalities and dark motives are prevalent.

For instance, in the wake of the first assassination attempt on Donald Trump, a false accusation arose online about the identity of the shooter and his motivations. The person who first posted this claim knew he was making up a name and stealing a photo. The intent was apparently to harass the Italian sports blogger whose photo was stolen. This fake conspiracy was seen over 300,000 times on the social platform X and picked up by multiple other conspiracists eager to fill the information gap about the assassination attempt.

Commercial conspiracists—the profiteers

Often when I encounter a conspiracy theory I ask: “What does the sharer have to gain? Are they telling me this because they have an evidence-backed concern, or are they trying to sell me something?”

When researchers tracked down the 12 people primarily responsible for the vast majority of anti-vaccine conspiracies online, most of them had a financial investment in perpetuating these misleading narratives.

Some people who fall into this category might truly believe their conspiracy, but their first priority is finding a way to make money from it. For instance, conspiracist Alex Jones bragged that his fans would “buy anything.” Fox News and its on-air personality Tucker Carlson publicized lies about voter fraud in the 2020 election to keep viewers engaged, while behind-the-scenes communications revealed they did not endorse what they espoused.

Profit doesn’t just mean money. People can also profit from spreading conspiracies if it garners them influence or followers, or protects their reputation. Even social media companies are reluctant to combat conspiracies because they know they attract more clicks.

Common conspiracists—the attention-getters

You don’t have to be a profiteer to like some attention. Plenty of regular people share content where they doubt the veracity or know it is false.

These posts are common: Friends, family, and acquaintances share the latest conspiracy theory with “could this be true?” queries or “seems close enough to the truth” taglines. Their accompanying comments show that sharers are, at minimum, unsure about the truthfulness of the content, but they share nonetheless. Many share without even reading past a headline. Still others, approximately 7 percent to 20 percent of social media users, share despite knowing the content is false. Why?

Some claim to be sharing to inform people “just in case” it is true. But this sort of “sound the alarm” reason actually isn’t that common.

Often, folks are just looking for attention or other personal benefit. They don’t want to miss out on a hot-topic conversation. They want the likes and shares. They want to “stir the pot.” Or they just like the message and want to signal to others that they share a common belief system.

For frequent sharers, it just becomes a habit.

The dangers of spreading lies

Over time, the opportunists may end up convincing themselves. After all, they will eventually have to come to terms with why they are engaging in unethical and deceptive, if not destructive, behavior. They may have a rationale for why lying is good. Or they may convince themselves that they aren’t lying by claiming they thought the conspiracy was true all along.

It’s important to be cautious and not believe everything you read. These opportunists don’t even believe everything they write—and share. But they want you to. So be aware that the next time you share an unfounded conspiracy theory, online or offline, you could be helping an opportunist. They don’t buy it, so neither should you. Be aware before you share. Don’t be what these opportunists derogatorily refer to as “a useful idiot.”

H. Colleen Sinclair is Associate Research Professor of Social Psychology at Louisiana State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The Conversation is an independent source of news and views, sourced from the academic and research community. Our team of editors work with these experts to share their knowledge with the wider public. Our aim is to allow for better understanding of current affairs and complex issues, and hopefully improve the quality of public discourse on them.

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Rocket Report: Falcon 9 second stage stumbles; Japanese rocket nears the end

rocket report, Science, Space / Rejus Almole / October 5, 2024

“I’m pretty darn confident I’m going to have a good day on Friday.”

United Launch Alliance’s Vulcan rocket sits on the pad at Space Launch Complex-41 (at Cape Canaveral at sunset in advance of the Cert-2 flight test. Credit: United Launch Alliance

Welcome to Edition 7.14 of the Rocket Report! For readers who don’t know, my second book was published last week. It’s titled Reentry, and tells the story behind the story of SpaceX’s development of the Falcon 9 rocket and Dragon spacecraft. The early reviews are great, and it made USA Today’s bestseller list this week. If you’re interested in rockets, and since you’re reading this newsletter we already know the answer to that, the book is probably up your alley.

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.

Vega C cleared for next launch in November. Italian rocket firm Avio successfully tested a redesigned Zefiro-40 solid rocket motor for the second time on Thursday, the European Space Agency said. This second firing follows an initial firing test of the motor in May 2024 and concludes the qualification tests for the new engine nozzle design of the Zefiro-40. This rocket motor powers the second stage of the Vega C rocket.

Flight three almost ready … The redesign of the motor was necessitated by the failure of a Vega C rocket in December 2022, which was just the second flight of the launch vehicle. Then, in June 2023, a test to re-certify the motor for flight also failed. Now that the second-stage issue appears to be resolved, Vega C is on the launch calendar for November of this year, although there’s the possibility the third mission of the rocket could slip a bit further. The rocket will be carrying the Sentinel-1C satellite to Sun-synchronous orbit. (submitted by EllPeaTea and Ken the Bin)

Impulse Space raises $150 million. Los Angeles-based space startup Impulse Space, which is led by renowned rocket scientist Tom Mueller, has raised $150 million in a new fundraising round led by venture capital firm Founders Fund, CNBC reports. Impulse is scaling a product line of orbital transfer vehicles, and so far is building two, the smaller Mira and the larger Helios. While rockets get satellites and payloads into orbit, like an airplane carrying passengers to a metro area, space tugs deliver them to specific destinations, like taxis taking those passengers home from the airport.

Taking the next step after launch … Mueller, who founded Impulse Space three years ago, said the funds will fuel growth of the company. “This means that we’re sufficiently funded through the development of Helios and the upgraded version Mira and out past the first flights of both of these products,” Mueller told the publication. Impulse flew its first mission, called LEO Express-1, with a Mira vehicle carrying and deploying a small satellite, last November. In Mueller’s view, while SpaceX reduced the cost to launch mass to orbit, the in-space delivery systems on the market are lacking. (submitted by Tom Nelson and Ken the Bin)

The easiest way to keep up with Eric Berger’s space reporting is to sign up for his newsletter, we’ll collect his stories in your inbox.

Polish company receives ESA support. Did you know there is a launch startup in Poland? Until this week, I confess I did not. However, that changed when the European Space Agency awarded 2.4 million euros to Poland’s SpaceForest for further development of its Perun rocket. SpaceForest has developed an 11.5-meter-tall sounding rocket capable of carrying payloads of up to 50 kilograms to an altitude of 150 kilometers, European Spaceflight reports.

Boosting up commercial companies … To date, the company has completed two test flights, one reaching an altitude of 22 kilometers and another topping out at 13 kilometers. With the new funding from ESA, SpaceForest will implement upgrades to the combustion chamber of its in-house developed SF1000 paraffin-powered hybrid rocket engine. ESA awarded the funding as part of the agency’s Boost! initiative. Adopted by member states in 2019, Boost! aims to foster the development of new commercial space transportation services. (submitted by Ken the Bin and EllPeaTea)

A new take on a kinetic launch system. Longshot Space is developing a straight-line kinetic launch system that will gradually accelerate payloads to hypersonic speeds before launching them to orbit, TechCrunch reports. The startup is betting it can achieve very, very low costs to orbit compared to a rocket, possibly as low as $10 per kilogram. The company raised $1.5 million in a pre-seed round in April 2023 and now, nearly 18 months later, Longshot closed a little over $5 million in combined venture capital and funding from the US Air Force’s TACFI program.

Pulling some serious Gs … The new capital will be used to build a large, 500-meter-long gun in the Nevada desert to push 100-kilogram payloads to Mach 5. The system has to be so long in order to keep acceleration forces low, which is better for both the vehicle and payload. For eventual space missions, Longshot is aiming to keep the maximum gravitational forces to 500–600 times the force of gravity. The company’s name serves a dual purpose, as its technology requires a longshot to reach space, and its prospects for success are probably a longshot. Nevertheless, it’s great to see someone trying new ideas. (submitted by Ken the Bin)

Falcon 9 rocket upper stage misfires. SpaceX is investigating a problem with the Falcon 9 rocket’s upper stage that caused it to reenter the atmosphere and fall into the sea outside of its intended disposal area after a launch last Saturday with a two-person crew heading to the International Space Station, Ars reports. The upper stage malfunction occurred after the Falcon 9 successfully deployed SpaceX’s Crew Dragon spacecraft carrying NASA astronaut Nick Hague and Russian cosmonaut Aleksandr Gorbunov on SpaceX’s Crew-9 mission. Hague and Gorbunov safely arrived at the space station Sunday to begin a five-month stay at the orbiting research complex.

Returning to flight shortly? … Safety warnings issued to mariners and pilots before the launch indicated the Falcon 9’s upper stage was supposed to fall somewhere in a narrow band stretching from southwest to northeast in the South Pacific east of New Zealand. Most of the rocket was expected to burn up during reentry, but SpaceX targeted a remote part of the ocean for disposal because some debris was likely to survive and reach the sea. This is the third time SpaceX has grounded the Falcon 9 rocket in less than three months, ending a remarkable run of flawless launches. A return to flight is expected as early as October 7 with the European Space Agency’s Hera spacecraft.

New Zealand seeks to reduce rocket regulations. New Zealand plans to implement a new “red tape-cutting” strategy for space and aviation by the end of 2025, the New Zealand Herald reports. “We have committed to having a world-class regulatory environment by the end of 2025,” Space Minister Judith Collins told the NZ Aerospace Summit recently. “To do that we’re introducing a light-touch regulatory approach that will significantly free up innovators to test their technology and ideas.”

Kiwis have a different attitude … The goal of reducing regulations is to allow companies to focus more on innovation and less on paperwork. New Zealand officials are motivated by concerns that Australia may seek to lure some of its space and aviation industries. Among the space companies with a significant presence in New Zealand are Rocket Lab, Dawn Aerospace, as well as smaller firms such as Astrix Astronautics. The move comes as US-based firms such as SpaceX, Varda, and others are pushing the country’s launch regulator, the Federal Aviation Administration, to be more nimble.

H2A nears the end of the road. Japan launched the classified IGS-Radar 8 satellite early Thursday with the second-to-last H-2A rocket, Space News reports. Developed and operated by Mitsubishi Heavy Industries, the H-2A rocket debuted in 2001 and has flown 49 times with a single failure, suffered in 2003. It has been a reliable medium-lift launch vehicle for Japan’s national space interests, as well as a handful of commercial space customers.

The rocket’s 50th launch will be its last … The final H-2A core stage is now completed and is scheduled for shipment to the Tanegashima Space Center. That launch, expected in late 2024, will carry the Global Observing SATellite for Greenhouse gases and Water cycle satellite. The H3 will succeed the H-2A. The new generation H3 had a troubled start, with its first flight in March 2023 suffering a second-stage engine failure. However, the new rocket has since flown successfully twice. (submitted by Ken the Bin)

Russians can invest in SpaceX now? Da. One of the odder stories this week concerns a Russian broker apparently offering access to privately held shares of SpaceX. An article in the Russian newspaper Kommersant suggests that a Moscow-based financial services company, Finam Holdings, managed to purchase a number of shares from a large foreign investment fund. The article says the minimum investment for Russians interested in buying into SpaceX is $10,000.

On bonds and broomsticks … Honestly, I have no idea about the legality of all this, but it sure smells funny. SpaceX, of course, periodically sells shares of the privately held company to investors. In addition, employees who receive shares in the company can sometimes sell their holdings. Given the existing sanctions on Russia due to the war on Ukraine and the potential for additional sanctions, it seems like these shareholders are definitely taking some risk.

ULA chief “supremely confident” in Vulcan’s second launch. The second flight of United Launch Alliance’s Vulcan rocket, planned for Friday morning, has a primary goal of validating the launcher’s reliability for delivering critical US military satellites to orbit. Tory Bruno, ULA’s chief executive, told reporters Wednesday that he is “supremely confident” the Vulcan rocket will succeed in accomplishing that objective, Ars reports. “As I come up on Cert-2, I’m pretty darn confident I’m going to have a good day on Friday, knock on wood,” Bruno said. “These are very powerful, complicated machines.”

A lengthy manifest to fly … The Vulcan launcher, a replacement for ULA’s Atlas V and Delta IV rockets, is on contract to haul the majority of the US military’s most expensive national security satellites into orbit over the next several years. If Friday’s test flight goes well, ULA is on track to launch at least one—and perhaps two—operational missions for the Space Force by the end of this year. The Space Force has already booked 25 launches on ULA’s Vulcan rocket for military payloads and spy satellites for the National Reconnaissance Office. Including the launch Friday, ULA has 70 Vulcan rockets in its backlog, mostly for the Space Force, the NRO, and Amazon’s Kuiper satellite broadband network.

NASA’s mobile launcher is on the move. NASA’s Exploration Ground Systems Program at Kennedy Space Center in Florida began moving the mobile launcher 1 from Launch Complex 39B along a 4.2-mile stretch back to the Vehicle Assembly Building this week. First motion of the mobile launcher, atop NASA’s crawler-transporter 2, occurred early on the morning of October 3, the space agency confirmed. Teams rolled the mobile launcher out to Kennedy’s Pad 39B in August 2023 for upgrades and a series of ground demonstration tests in preparation for the Artemis II mission.

Stacking operations when? … After arriving outside the Vehicle Assembly Building later on Thursday, the launch tower will be moved into High Bay 3 on Friday. This is all in preparation for stacking the Space Launch System rocket for the Artemis II mission, which is nominally scheduled for September 2025 but may slip further. NASA has not publicly said when stacking operations will begin, and this depends on when the space agency makes a final decision on whether to fly the Orion spacecraft with its heat shield as-is or adopt a different plan. Stacking will take several months.

Next three launches

Oct. 4: Vulcan | Cert-2 mission | Cape Canaveral Space Force Station, Florida | 10: 00 UTC

Oct. 7: Falcon 9 | Hera | Cape Canaveral Space Force Station, Florida | 14: 52 UTC

Oct. 9: Falcon 9 | OneWeb-20 | Vandenberg Space Force Base, California | 06: 03 UTC

Eric Berger is the senior space editor at Ars Technica, covering everything from astronomy to private space to NASA policy, and author of two books: Liftoff, about the rise of SpaceX; and Reentry, on the development of the Falcon 9 rocket and Dragon. A certified meteorologist, Eric lives in Houston.

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Helene ravaged the NC plant that makes 60% of the country’s IV fluid supply

baxter, health, Helene, hospitals, IV fluid, medical supply, medical supply chain, North Carolina, Science, supply chain / Paul Patrick / October 4, 2024

Hurricane Helene’s catastrophic damage and flooding to the Southeastern states may affect the country’s medical supply chain.

Hospitals nationwide are bracing for a possible shortage of essential intravenous fluids after the cataclysmic storm inundated a vital manufacturing plant in North Carolina.

The plant is Baxter International’s North Cove manufacturing facility in Marion, which is about 35 miles northeast of Asheville. Helene unleashed unprecedented amounts of rain throughout the western part of the state, killing dozens and ravaging numerous communities, homes, and other structures, including the plant.

The North Cove plant produces 60 percent of the country’s supply of IV solutions, typically producing 1.5 million bags per day, according to the American Hospital Association. The dozens of sterile solutions Baxter makes at the facility are used for everything from intravenous rehydration and drug delivery to peritoneal dialysis used to treat kidney failure.

“Our hearts and thoughts are with all those affected by Hurricane Helene,” Baxter CEO José Almeida said in a statement on September 29. “The safety of our employees, their families, and the communities in which we operate remains our utmost concern, and we are committed to helping ensure reliable supply of products to patients. Remediation efforts are already underway, and we will spare no resource—human or financial—to resume production and help ensure patients and providers have the products they need.”

Critical supply

On October 2, Mass General Brigham, Massachusetts’ largest hospital and health care system, warned employees via email of a “serious and immediate IV fluid shortage,” according to the Boston Globe.

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How London’s Crystal Palace was built so quickly

architecture, Crystal Palace, engineering, Science / Mike M. / October 4, 2024

London’s Great Exhibition of 1851 attracted some 6 million people eager to experience more than 14,000 exhibitors showcasing 19th-century marvels of technology and engineering. The event took place in the Crystal Palace, a 990,000-square-foot building of cast iron and plate glass originally located in Hyde Park. And it was built in an incredible 190 days. According to a recent paper published in the International Journal for the History of Engineering and Technology, one of the secrets was the use of a standardized screw thread, first proposed 10 years before its construction, although the thread did not officially become the British standard until 1905.

“During the Victorian era there was incredible innovation from workshops right across Britain that was helping to change the world,” said co-author John Gardner of Anglia Ruskin University (ARU). “In fact, progress was happening at such a rate that certain breakthroughs were perhaps never properly realized at the time, as was the case here with the Crystal Palace. Standardization in engineering is essential and commonplace in the 21st century, but its role in the construction of the Crystal Palace was a major development.”

The design competition for what would become the Crystal Palace was launched in March 1850, with a deadline four weeks later, and the actual, fully constructed building opened on May 1, 1851. The winning design, by Joseph Patterson, wasn’t chosen until quite late in the game after numerous designs had been rejected—most because they were simply too far above the £100,000 budget.

Joseph Paxton's first sketch for the Great Exhibition Building, c. 1850, using pen and ink on blotting paper — Joseph Paxton’s first sketch for the Great Exhibition Building, c. 1850, using pen and ink on blotting paper. Credit: Victoria and Albert Museum/CC BY-SA 3.0

Patterson’s design called for what was essentially a giant conservatory consisting of a multi-dimensional grid of 24-foot modules. The design elements included 3,300 supporting columns with four flange faces, drilled so they could be bolted to connecting and base pieces. (The hollow columns did double duty as drainage pipes for rainwater.) The design also called for diagonal bracing (aka cross bracing) for additional stability.

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ULA’s second Vulcan rocket lost part of its booster and kept going

launch, military space, Science, Space, united launch alliance, vulcan / Kris Guyer / October 4, 2024

The US Space Force says this test flight was critical for certifying Vulcan for military missions.

United Launch Alliance’s Vulcan rocket, under contract for dozens of flights for the US military and Amazon’s Kuiper broadband network, lifted off from Florida on its second test flight Friday, suffered an anomaly with one of its strap-on boosters, and still achieved a successful mission, the company said in a statement.

This test flight, known as Cert-2, is the second certification mission for the new Vulcan rocket, a milestone that paves the way for the Space Force to clear ULA’s new rocket to begin launching national security satellites in the coming months.

While ULA said the Vulcan rocket continued to hit its marks during the climb into orbit Friday, engineers are investigating what happened with one of its solid rocket boosters shortly after liftoff.

After a last-minute aborted countdown earlier in the morning, the 202-foot-tall (61.6-meter) Vulcan rocket lit its twin methane-fueled BE-4 engines and two side-mounted solid rocket boosters to climb away from Cape Canaveral Space Force Station, Florida, at 7: 25 am EDT (11: 25 UTC) Friday.

A little tilt

As the rocket arced east from Cape Canaveral, a shower of sparks suddenly appeared at the base of the Vulcan rocket around 37 seconds into the mission. The exhaust plume from one of the strap-on boosters, made by Northrop Grumman, changed significantly, and the rocket slightly tilted on its axis before the guidance system and main engines made a steering correction.

Videos from the launch show the booster’s nozzle, the bell-shaped exhaust exit cone at the bottom of the booster, fall away from the rocket.

“It looks dramatic, like all things on a rocket,” Bruno wrote on X. “But it’s just the release of the nozzle. No explosions occurred.”

During the ascent of the Vulcan rocket on the #Cert2 mission, there appeared to be an issue with the solid rocket booster on the right side of the vehicle as seen from the KSC Press Site. However, the Centaur was able to reach orbit.https://t.co/3iwWLVWZHp

📹: @ABernNYC pic.twitter.com/5h06ffNMXr

— Spaceflight Now (@SpaceflightNow) October 4, 2024

The Federal Aviation Administration, which licenses commercial space launches in the United States, said in a statement that it assessed the booster anomaly and “determined no investigation is warranted at this time.” The FAA is not responsible for regulating launch vehicle anomalies unless they impact public safety.

The Vulcan rocket comes in several configurations, with zero, two, four, or six solid-fueled boosters clustered around the liquid-fueled core stage. ULA can tailor the configuration based on the parameters of each mission, such as payload mass and target orbit.

The boosters, which Northrop Grumman calls graphite epoxy motors, are 63 inches (1.6 meters) in diameter and 72 feet (22 meters) long. Their nozzles are made of a composite heat-resistant carbon-phenolic material.

Bruno added that the rest of the damaged booster’s composite casing held up fine during its roughly 90-second burn, but the anomaly caused “reduced, asymmetric thrust” that the rocket compensated for during the rest of its ascent into space.

The Federal Aviation Administration, which regulates commercial space launches, is not immediately requiring an investigation into the booster anomaly. The FAA said it is “assessing the operation and will issue an updated statement if the agency determines an investigation is warranted.”

Remarkably, the Vulcan rocket soldiered on and jettisoned both strap-on boosters to fall into the Atlantic Ocean. They’re not designed for recovery, so ULA and Northrop Grumman engineers will have to piece together what happened from imagery and performance data beamed down from the rocket in flight.

The BE-4 main engines, supplied by Jeff Bezos’ space company Blue Origin, appeared to work flawlessly for the first five minutes of the flight. The core stage shut down its engines and separated from Vulcan’s Centaur upper stage, which ignited two Aerojet Rocketdyne RL10 engines to propel the rocket into orbit.

The second Vulcan rocket lifts off from Cape Canaveral Space Force Station, Florida, powered by two methane-fueled BE-4 engines and two solid rocket boosters. Credit: United Launch Alliance

Live data displayed on ULA’s webcast of the launch suggested the RL10 engines fired for approximately 20 seconds longer than planned, apparently to compensate for the lower thrust from the damaged booster during the first phase of the flight. The Centaur upper stage completed a second burn about a half-hour into the mission.

The rocket did not carry a real satellite. Earlier this year, ULA decided to launch a dummy payload to simulate the mass of a spacecraft, when it became clear the original payload for Vulcan’s second flight—Sierra Space’s first Dream Chaser spaceplane—would not be ready to fly this fall. ULA says it self-funded most of the cost of the Cert-2 test flight, which Bruno suggested was somewhere below $100 million.

Bullseye insertion

“Orbital insertion was perfect,” Bruno wrote on X.

The Centaur engines were supposed to fire a third time later Friday to send the rocket on a trajectory to escape Earth orbit and head into the Solar System. ULA also planned to perform experiments with the Centaur upper stage to demonstrate technologies and capabilities for longer-duration missions that could eventually last days, weeks, or months. The company did not provide an update on the results of these experiments.

Friday morning’s launch follows the debut test flight of the Vulcan rocket on January 8, which sent a commercial lunar lander from Astrobotic on a trajectory toward the Moon. The launch in January was nearly perfect.

ULA is a 50-50 joint venture between Boeing and Lockheed Martin, which merged their rocket divisions to form a single company in 2006. SpaceX, with its Falcon 9 and Falcon Heavy rockets, is ULA’s main competitor in the market for launching large US military satellites into orbit.

In 2020, the Pentagon awarded ULA and SpaceX multibillion-dollar “Phase 2” contracts to share responsibilities for launching dozens of national security space missions through 2027. Defense officials selected ULA’s Vulcan rocket to launch 25 national security missions, the majority of the launches up for competition. The rest went to SpaceX’s Falcon 9 and Falcon Heavy, which started delivering on its Phase 2 contract in January 2023.

Later this year, the Space Force is expected to select up to three companies—almost certainly ULA, SpaceX, and perhaps Blue Origin with its soon-to-debut New Glenn rocket—in a fresh competition to be eligible for contracts to launch the military’s largest spacecraft through 2029.

The Space Force required ULA to complete two successful Vulcan test flights before clearing the new rocket for launching military satellites. Despite the booster malfunction, ULA officials clearly believe the Vulcan rocket did enough Friday for the Space Force to certify it.

“The success of Vulcan’s second certification flight heralds a new age of forward-looking technology committed to meeting the ever-growing requirements of space launch and supporting our nation’s assured access to space,” Bruno said in a statement. “We had an observation on one of our solid rocket boosters (SRBs) that we are reviewing, but we are overall pleased with the rocket’s performance and had a bullseye insertion.”

A closer view of the Vulcan rocket’s BE-4 main engines and twin solid-fueled boosters. Credit: United Launch Alliance

In a press release after Friday’s launch, the Space Force hailed the test flight as a “certification milestone.”

“This is a significant achievement for both ULA and an important milestone for the nation’s strategic space lift capability,” said Brig. Gen. Kristin Panzenhagen, Space Systems Command’s program executive officer for assured access to space. “The Space Force’s partnership with launch companies, such as ULA, are absolutely critical in deploying on-orbit capabilities that protect our national interests.

“We are already starting to review the performance data from this launch, and we look forward to Vulcan meeting the certification requirements for a range of national security space missions,” Panzenhagen said in a statement.

The Space Force is eager for Vulcan to become operational. Some of the military’s most critical reconnaissance, communications, and missile warning satellites are slated to fly on Vulcan rockets.

Ramping up

Going into Friday’s test flight, ULA and the Space Force hoped to launch one or two more Vulcan rockets by the end of the year, both with US Space Force payloads. The timing of the next Vulcan launch, assuming the Space Force certifies the new rocket, will likely hinge on the outcome of the investigation into the booster anomaly.

ULA has already transported all major components of the next Vulcan rocket from its factory in Alabama to Cape Canaveral for final launch preparations. The company has a backlog of 69 Vulcan flights, counting missions for the Space Force, the National Reconnaissance Office, Amazon’s Kuiper network, and Sierra Space’s Dream Chaser spaceplane to resupply the International Space Station.

In a prelaunch briefing with reporters, Bruno said ULA aims to launch up to 20 times next year. Roughly half of that number will be Vulcan flights, and the rest will be Atlas V rockets, which ULA is retiring in favor of Vulcan.

There are 15 Atlas V rockets left to fly, primarily for Amazon and Boeing’s Starliner crew capsule. The nozzle failure Friday may also affect the schedule for Atlas V launches because the soon-to-retire rocket uses a similar booster design from Northrop Grumman.

ULA eventually wants to launch up to 25 Vulcan rockets per year from its launch pads at Cape Canaveral and at Vandenberg Space Force Base, California. The launch provider is outfitting a second assembly building in Florida to stack Vulcan rockets, a capability that will shorten the time between liftoffs. ULA is modifying its Atlas V launch pad in California to support Vulcan flights there next year.

ULA announced the Vulcan rocket in 2015 to replace the Atlas V and Delta IV rockets, which had stellar success records but were not cost-competitive with SpaceX’s partially reusable Falcon 9. The Atlas V also uses a Russian main engine, a situation that became politically untenable after Russia’s annexation of Crimea in 2014, and more so after the Russian invasion of Ukraine in 2022. The final Russian engines for the Atlas V arrived in the United States in 2021.

The Vulcan rocket is somewhat less expensive than the Atlas V, and significantly cheaper than the Delta IV, but still more costly than SpaceX’s Falcon 9. There is a closer price parity between Vulcan and SpaceX’s Falcon Heavy rocket.

Bruno hinted at the cost of developing the rocket in his roundtable discussion with reporters earlier this week.

“Developing a rocket, and then the infrastructure to develop a new space launch vehicle, the rule of thumb is it costs you somewhere between $5 billion and $7 billion,” Bruno said. “Vulcan is not outside the rule of thumb.”

Updated at 5: 15 pm EDT (21: 15 UTC) with new FAA statement.

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.

ULA’s second Vulcan rocket lost part of its booster and kept going Read More »

The more sophisticated AI models get, the more likely they are to lie

AI, Science / Mike M. / October 4, 2024

Human feedback training may incentivize providing any answer—even wrong ones.

Image of a Pinocchio doll with a long nose and a small green sprig at the end.

When a research team led by Amrit Kirpalani, a medical educator at Western University in Ontario, Canada, evaluated ChatGPT’s performance in diagnosing medical cases back in August 2024, one of the things that surprised them was the AI’s propensity to give well-structured, eloquent but blatantly wrong answers.

Now, in a study recently published in Nature, a different group of researchers tried to explain why ChatGPT and other large language models tend to do this. “To speak confidently about things we do not know is a problem of humanity in a lot of ways. And large language models are imitations of humans,” says Wout Schellaert, an AI researcher at the University of Valencia, Spain, and co-author of the paper.

Smooth operators

Early large language models like GPT-3 had a hard time answering simple questions about geography or science. They even struggled with performing simple math such as “how much is 20 +183.” But in most cases where they couldn’t identify the correct answer, they did what an honest human being would do: They avoided answering the question.

The problem with the non-answers is that large language models were intended to be question-answering machines. For commercial companies like Open AI or Meta that were developing advanced LLMs, a question-answering machine that answered “I don’t know” more than half the time was simply a bad product. So, they got busy solving this problem.

The first thing they did was scale the models up. “Scaling up refers to two aspects of model development. One is increasing the size of the training data set, usually a collection of text from websites and books. The other is increasing the number of language parameters,” says Schellaert. When you think about an LLM as a neural network, the number of parameters can be compared to the number of synapses connecting its neurons. LLMs like GPT-3 used absurd amounts of text data, exceeding 45 terabytes, for training. The number of parameters used by GPT-3 was north of 175 billion.

But it was not enough.

Scaling up alone made the models more powerful, but they were still bad at interacting with humans—slight variations in how you phrased your prompts could lead to drastically different results. The answers often didn’t feel human-like and sometimes were downright offensive.

Developers working on LLMs wanted them to parse human questions better and make answers more accurate, more comprehensible, and consistent with generally accepted ethical standards. To try to get there, they added an additional step: supervised learning methods, such as reinforcement learning, with human feedback. This was meant primarily to reduce sensitivity to prompt variations and to provide a level of output-filtering moderation intended to curb hateful-spewing Tay chatbot-style answers.

In other words, we got busy adjusting the AIs by hand. And it backfired.

AI people pleasers

“The notorious problem with reinforcement learning is that an AI optimizes to maximize reward, but not necessarily in a good way,” Schellaert says. Some of the reinforcement learning involved human supervisors who flagged answers they were not happy with. Since it’s hard for humans to be happy with “I don’t know” as an answer, one thing this training told the AIs was that saying “I don’t know” was a bad thing. So, the AIs mostly stopped doing that. But another, more important thing human supervisors flagged was incorrect answers. And that’s where things got a bit more complicated.

AI models are not really intelligent, not in a human sense of the word. They don’t know why something is rewarded and something else is flagged; all they are doing is optimizing their performance to maximize reward and minimize red flags. When incorrect answers were flagged, getting better at giving correct answers was one way to optimize things. The problem was getting better at hiding incompetence worked just as well. Human supervisors simply didn’t flag wrong answers that appeared good and coherent enough to them.

In other words, if a human didn’t know whether an answer was correct, they wouldn’t be able to penalize wrong but convincing-sounding answers.

Schellaert’s team looked into three major families of modern LLMs: Open AI’s ChatGPT, the LLaMA series developed by Meta, and BLOOM suite made by BigScience. They found what’s called ultracrepidarianism, the tendency to give opinions on matters we know nothing about. It started to appear in the AIs as a consequence of increasing scale, but it was predictably linear, growing with the amount of training data, in all of them. Supervised feedback “had a worse, more extreme effect,” Schellaert says. The first model in the GPT family that almost completely stopped avoiding questions it didn’t have the answers to was text-davinci-003. It was also the first GPT model trained with reinforcement learning from human feedback.

The AIs lie because we told them that doing so was rewarding. One key question is when and how often do we get lied to.

Making it harder

To answer this question, Schellaert and his colleagues built a set of questions in different categories like science, geography, and math. Then, they rated those questions based on how difficult they were for humans to answer, using a scale from 1 to 100. The questions were then fed into subsequent generations of LLMs, starting from the oldest to the newest. The AIs’ answers were classified as correct, incorrect, or evasive, meaning the AI refused to answer.

The first finding was that the questions that appeared more difficult to us also proved more difficult for the AIs. The latest versions of ChatGPT gave correct answers to nearly all science-related prompts and the majority of geography-oriented questions up until they were rated roughly 70 on Schellaert’s difficulty scale. Addition was more problematic, with the frequency of correct answers falling dramatically after the difficulty rose above 40. “Even for the best models, the GPTs, the failure rate on the most difficult addition questions is over 90 percent. Ideally we would hope to see some avoidance here, right?” says Schellaert. But we didn’t see much avoidance.

Instead, in more recent versions of the AIs, the evasive “I don’t know” responses were increasingly replaced with incorrect ones. And due to supervised training used in later generations, the AIs developed the ability to sell those incorrect answers quite convincingly. Out of the three LLM families Schellaert’s team tested, BLOOM and Meta’s LLaMA have released the same versions of their models with and without supervised learning. In both cases, supervised learning resulted in the higher number of correct answers, but also in a higher number of incorrect answers and reduced avoidance. The more difficult the question and the more advanced model you use, the more likely you are to get well-packaged, plausible nonsense as your answer.

Back to the roots

One of the last things Schellaert’s team did in their study was to check how likely people were to take the incorrect AI answers at face value. They did an online survey and asked 300 participants to evaluate multiple prompt-response pairs coming from the best performing models in each family they tested.

ChatGPT emerged as the most effective liar. The incorrect answers it gave in the science category were qualified as correct by over 19 percent of participants. It managed to fool nearly 32 percent of people in geography and over 40 percent in transforms, a task where an AI had to extract and rearrange information present in the prompt. ChatGPT was followed by Meta’s LLaMA and BLOOM.

“In the early days of LLMs, we had at least a makeshift solution to this problem. The early GPT interfaces highlighted parts of their responses that the AI wasn’t certain about. But in the race to commercialization, that feature was dropped, said Schellaert.

“There is an inherent uncertainty present in LLMs’ answers. The most likely next word in the sequence is never 100 percent likely. This uncertainty could be used in the interface and communicated to the user properly,” says Schellaert. Another thing he thinks can be done to make LLMs less deceptive is handing their responses over to separate AIs trained specifically to search for deceptions. “I’m not an expert in designing LLMs, so I can only speculate what exactly is technically and commercially viable,” he adds.

It’s going to take some time, though, before the companies that are developing general-purpose AIs do something about it, either out of their own accord or if forced by future regulations. In the meantime, Schellaert has some suggestions on how to use them effectively. “What you can do today is use AI in areas where you are an expert yourself or at least can verify the answer with a Google search afterwards. Treat it as a helping tool not as a mentor. It’s not going to be a teacher that proactively shows you where you went wrong. Quite the opposite. When you nudge it enough, it will happily go along with your faulty reasoning,” Schellaert says.

Nature, 2024. DOI: 10.1038/s41586-024-07930-y

Jacek Krywko is a freelance science and technology writer who covers space exploration, artificial intelligence research, computer science, and all sorts of engineering wizardry.

The more sophisticated AI models get, the more likely they are to lie Read More »

Human case of H5N1 suspected in California amid rapid dairy spread

avian influenza, bird flu, California, CDC, dairy cows, H5N1, health, Infectious disease, milk, Science / Paul Patrick / October 3, 2024

California’s infections bring the country’s total number of affected herds to 255 in 14 states, according to the USDA.

In a new release Thursday, California health officials worked to ease alarm about the human case, emphasizing that the risk to the general public remains low.

“Ongoing health checks of individuals who interact with potentially infected animals helped us quickly detect and respond to this possible human case. Fortunately, as we’ve seen in other states with human infections, the individual has experienced mild symptoms,” Tomás Aragón, director of California’s Department of Public Health, said. “We want to emphasize that the risk to the general public is low, and people who interact with potentially infected animals should take prevention measures.”

The release noted that in the past four months, the health department has distributed more than 340,000 respirators, 1.3 million gloves, 160,000 goggles and face shields, and 168,000 bouffant caps to farm workers. The state has also received 5,000 doses of seasonal flu vaccine earmarked for farm workers and is working to distribute those vaccines to local health departments.

Still, herd infections and human cases continue to tick up. Influenza researchers and other health experts are anxiously following the unusual dairy outbreak—the first time an avian influenza is known to have spilled over to and caused an outbreak in cattle. The more opportunities the virus has to spread and adapt to mammals, the more chances it could begin spreading among humans, potentially sparking an outbreak or even a pandemic.

Human case of H5N1 suspected in California amid rapid dairy spread Read More »

Strange “biotwang” ID’d as Bryde’s whale call

animal behavior, baleen whales, bioacoustics, Biology, Science, whale communication, whales / Paul Patrick / October 3, 2024

In 2014, researchers monitoring acoustic recordings from the Mariana Archipelago picked up an unusual whale vocalization with both low- and high-frequency components. It seemed to be a whale call, but it sounded more mechanical than biological and has since been dubbed a “biotwang.”

Now a separate team of scientists has developed a machine-learning model to scan a dataset of recordings of whale vocalizations from various species to help identify the source of such calls. Combining that analysis with visual observations allowed the team to identify the source of the biotwang: a species of baleen whales called Bryde’s (pronounced “broodus”) whales. This should help researchers track populations of these whales as they migrate to different parts of the world, according to a recent paper published in the journal Frontiers in Marine Science.

Marine biologists often rely on a powerful tool called passive acoustic monitoring for long-term data collection of the ocean’s acoustic environment, including whale vocalizations. Bryde’s whale calls tend to be regionally specific, per the authors. For instance, calls in the eastern North Pacific are pretty well documented, with frequencies typically falling below 100 Hz, augmented by harmonic frequencies as high as 400 Hz. Far less is known about the sounds made by Bryde’s whales in the western and central North Pacific, since for many years there were only three known recordings of those vocalizations—including a call dubbed “Be8” (starting at 45 Hz with multiple harmonics) and mother-calf calls.

That changed with the detection of the biotwang in 2014. It’s quite a distinctive, complex call that typically lasts about 3.5 seconds, with five stages, starting at around 30 Hz and ending with a metallic sound that can reach as high as 8,000 Hz. “It’s a real weird call,” co-author Ann Allen, a scientist at NOAA Fisheries, told Ars. “Anybody who wasn’t familiar with whales would think it was some sort of artificial sound, made by a naval ship.” The 2014 team was familiar with whale vocalizations and originally attributed the strange sound to baleen whales. But that particular survey was autonomous, and without accompanying visual observations, the scientists could not definitively confirm their hypothesis.

Strange “biotwang” ID’d as Bryde’s whale call Read More »

Ants learned to farm fungi during a mass extinction

agriculture, ants, Biology, evolution, fungi, Science / Paul Patrick / October 3, 2024

Timing is everything

Tracing the lineages of agricultural ants to their most recent common ancestor revealed that the ancestor probably lived through the end-Cretaceous mass extinction—the one that killed off the dinosaurs. The researchers argue that the two were almost certainly related. Current models suggest that there was so much dust in the atmosphere after the impact that set off the mass extinction that photosynthesis shut down for nearly two years, meaning minimal plant life. By contrast, the huge amount of dead material would allow fungi to flourish. So, it’s not surprising that ants started to adapt to use what was available to them.

That explains the huge cluster of species that cooperate with fungi. However, most of the species that engage in organized farming don’t appear until roughly 35 million years after the mass extinction, at the end of the Eocene (that’s about 33 million years before the present period). The researchers suggest that the climate changes that accompanied the transition to the Oligocene included a drying out of the tropical Americas, where the fungus-farming ants had evolved. This would cut down on the availability of fungi in the wild, potentially selecting for the ability of species that could propagate fungal species on their own.

This also corresponds to the origins of the yeast strains used by farming ants, as well as the most specialized agricultural fungal species. But it doesn’t account for the origin of coral fungus farmers, which seems to have occurred roughly 10 million years later.

The work gives us a much clearer picture of the origin of agriculture in ants and some reasonable hypotheses regarding the selective pressures that might have led to its evolution. In the long term, however, the biggest advance here may be the resources generated during this study. Ultimately, we’d like to understand the genetic basis for the changes in the ants’ behavior, as well as how the fungi have adapted to better provide for their farmers. To do that, we’ll need to compare the genomes of agricultural species with their free-living relatives. The DNA gathered for this study will ultimately be needed to pursue those questions.

Science, 2024. DOI: 10.1126/science.adn7179 (About DOIs).

Ants learned to farm fungi during a mass extinction Read More »

Popular gut probiotic completely craps out in randomized controlled trial

activia, B. lactis, Bifidobacterium animalis subsp. lactis, constipation, digestive disorder, digestive system, functional constipation, health, probiotic, Science, yogurt / Kris Guyer / October 3, 2024

Any striking marketing claims in companies’ ads about the gut benefits of a popular probiotic may be full of, well, the same thing that has their target audience backed up.

In a randomized controlled trial, the probiotic Bifidobacterium animalis subsp. lactis—used in many probiotic products, including Dannon’s Activia yogurts—did nothing to improve bowel health in people with constipation, according to data from a randomized triple-blind placebo-controlled clinical trial published Wednesday in JAMA Network Open.

The study adds to a mixed and mostly unconvincing body of scientific literature on the bowel benefits of the bacterium, substrains of which are sometimes sold with faux scientific-sounding names in products. Dannon, for instance, previously marketed its substrain, DN-173 010, as “Bifidus regularis.”

Digested data

For the new study, researchers in China recruited 228 middle-aged adults, 85 percent of whom were women. The participants, all from Shanghai, were considered healthy based on medical testing and records, except for reporting functional constipation. This is a condition defined by having two or more signs of difficulty evacuating the bowels, such as frequent straining and having rock-like stool. For the study, the researchers included the additional criterion that participants have three or fewer complete, spontaneous bowel movements (CSBMs) per week.

The participants were randomized to take either a placebo (117 participants) or the probiotic (112 participants) every day for eight weeks. Both groups got packets of sweetened powder that participants added to a glass of water taken before breakfast each morning. In addition to a sweetener, the daily probiotic packets contained freeze-dried Bifidobacterium animalis subsp. lactis substrain HN019, which is used in some commercial probiotic products. The first dose had a concentration of 7 × 10⁹ colony-forming units (CFUs), then participants shifted to a daily dose of 4.69 × 10⁹ CFUs. Many probiotic products have doses of B. lactis in ranges from 1 × 10⁹ to 17 × 10⁹.

ULA hasn’t given up on developing a long-lived cryogenic space tug

Centaur, Commercial space, launch, military space, Science, Space, united launch alliance, vulcan / Kris Guyer / October 3, 2024

On Friday’s launch, United Launch Alliance will test the limits of its Centaur upper stage.

United Launch Alliance’s second Vulcan rocket underwent a countdown dress rehearsal Tuesday. Credit: United Launch Alliance

The second flight of United Launch Alliance’s Vulcan rocket, planned for Friday morning, has a primary goal of validating the launcher’s reliability for delivering critical US military satellites to orbit.

Tory Bruno, ULA’s chief executive, told reporters Wednesday that he is “supremely confident” the Vulcan rocket will succeed in accomplishing that objective. The Vulcan’s second test flight, known as Cert-2, follows a near-flawless debut launch of ULA’s new rocket on January 8.

“As I come up on Cert-2, I’m pretty darn confident I’m going to have a good day on Friday, knock on wood,” Bruno said. “These are very powerful, complicated machines.”

The Vulcan launcher, a replacement for ULA’s Atlas V and Delta IV rockets, is on contract to haul the majority of the US military’s most expensive national security satellites into orbit over the next several years. The Space Force is eager to certify Vulcan to launch these payloads, but military officials want to see two successful test flights before committing one of its satellites to flying on the new rocket.

If Friday’s test flight goes well, ULA is on track to launch at least one—and perhaps two—operational missions for the Space Force by the end of this year. The Space Force has already booked 25 launches on ULA’s Vulcan rocket for military payloads and spy satellites for the National Reconnaissance Office. Including the launch Friday, ULA has 70 Vulcan rockets in its backlog, mostly for the Space Force, the NRO, and Amazon’s Kuiper satellite broadband network.

The Vulcan rocket is powered by two methane-fueled BE-4 engines produced by Jeff Bezos’ space company Blue Origin, and ULA can mount zero, two, four, or six strap-on solid rocket boosters from Northrop Grumman around the Vulcan’s first stage to propel heavier payloads to space. The rocket’s Centaur V upper stage is fitted with a pair of hydrogen-burning RL10 engines from Aerojet Rocketdyne.

The second Vulcan rocket will fly in the same configuration as the first launch earlier this year, with two strap-on solid-fueled boosters. The only noticeable modification to the rocket is the addition of some spray-on foam insulation around the outside of the first stage methane tank, which will keep the cryogenic fuel at the proper temperature as Vulcan encounters aerodynamic heating on its ascent through the atmosphere.

“This will give us just over one second more usable propellant,” Bruno wrote on X.

There is one more change from Vulcan’s first launch, which boosted a commercial lunar lander for Astrobotic on a trajectory toward the Moon. This time, there are no real spacecraft on the Vulcan rocket. Instead, ULA mounted a dummy payload to the Centaur V upper stage to simulate the mass of a functioning satellite.

ULA originally planned to launch Sierra Space’s first Dream Chaser spaceplane on the second Vulcan rocket. But the Dream Chaser won’t be ready to fly its first mission to resupply the International Space Station until next year. Under pressure from the Pentagon, ULA decided to move ahead with the second Vulcan launch without a payload at the company’s own expense, which Bruno tallied in the “high tens of millions of dollars.”

Heliocentricity

The test flight will begin with liftoff from Cape Canaveral Space Force Station, Florida, during a three-hour launch window opening at 6 am EDT (10: 00 UTC). The 202-foot-tall (61.6-meter) Vulcan rocket will head east over the Atlantic Ocean, shedding its boosters, first stage, and payload fairing in the first few minutes of flight.

The Centaur upper stage will fire its RL10 engines two times, completing the primary mission within about 35 minutes of launch. The rocket will then continue on for a series of technical demonstrations before ending up on an Earth escape trajectory into a heliocentric orbit around the Sun.

“We have a number of experiments that we’re conducting that are really technology demonstrations and measurements that are associated with our high-performance, longer-duration version of Centaur V that we’ll be introducing in the future,” Bruno said. “And these will help us go a little bit faster on that development. And, of course, because we don’t have an active spacecraft as a payload, we also have more instrumentation that we’re able to use for just characterizing the vehicle.”

The Centaur V upper stage for the Vulcan rocket. Credit: United Launch Alliance

ULA engineers have worked on the design of a long-lived upper stage for more than a decade. Their vision was to develop an upper stage fed by super-efficient cryogenic liquid hydrogen and liquid oxygen propellants that could generate its own power and operate in space for days, weeks, or longer rather than an upper stage’s usual endurance limit of several hours. This would allow the rocket to not only deliver satellites into bespoke high-altitude orbits but also continue on to release more payloads at different altitudes or provide longer-term propulsion in support of other missions.

The concept was called the Advanced Cryogenic Evolved Stage (ACES). ULA’s corporate owners, Boeing and Lockheed Martin, never authorized the full development of ACES, and the company said in 2020 that it was no longer pursuing the ACES concept.

The Centaur V upper stage currently used on the Vulcan rocket is a larger version of the thin-walled, pressure-stabilized Centaur upper stage that has been flying since the 1960s. Bruno said the Centaur V design, as it is today, offers as much as 12 hours of operating life in space. This is longer than any other existing rocket using cryogenic propellants, which can boil off over time.

ULA’s chief executive still harbors an ambition for regaining some of the same capabilities promised by ACES.

“What we are looking to do is to extend that by orders of magnitude,” Bruno said. “And what that would allow us to do is have a in-space transportation capability for in-space mobility and servicing and things like that.”

Space Force leaders have voiced a desire for future spacecraft to freely maneuver between different orbits, a concept the military calls “dynamic space operations.” This would untether spacecraft operations from fuel limitations and eventually require the development of in-orbit refueling, propellant depots, or novel propulsion technologies.

No one has tried to store large amounts of super-cold propellants in space for weeks or longer. Accomplishing this is a non-trivial thermal problem, requiring insulation to keep heat from the Sun from reaching the liquid cryogenic propellant, stored at temperatures of several hundred degrees below zero.

Bruno hesitated to share details of the experiments ULA plans for the Centaur V upper stage on Friday’s test flight, citing proprietary concerns. He said the experiments will confirm analytical models about how the upper stage performs in space.

“Some of these are devices, some of these are maneuvers because maneuvers make a difference, and some are related to performance in a way,” he said. “In some cases, those maneuvers are helping us with the thermal load that tries to come in and boil off the propellants.”

Eventually, ULA would like to eliminate hydrazine attitude control fuel and battery power from the Centaur V upper stage, Bruno said Wednesday. This sounds a lot like what ULA wanted to do with ACES, which would have used an internal combustion engine called Integrated Vehicle Fluids (IVF) to recycle gasified waste propellants to pressurize its propellant tanks, generate electrical power, and feed thrusters for attitude control. This would mean the upper stage wouldn’t need to rely on hydrazine, helium, or batteries.

ULA hasn’t talked much about the IVF system in recent years, but Bruno said the company is still developing it. “It’s part of all of this, but that’s all I will say, or I’ll start revealing what all the gadgets are.”

A comparison between ULA’s legacy Centaur upper stage and the new Centaur V. Credit: United Launch Alliance

George Sowers, former vice president and chief scientist at ULA, was one of the company’s main advocates for extending the lifetime of upper stages and developing technologies for refueling and propellant depot. He retired from ULA in 2017 and is now a professor at the Colorado School of Mines and an independent aerospace industry consultant.

In an interview with Ars earlier this year, Sowers said ULA solved many of the problems with keeping cryogenic propellants at the right temperature in space.

“We had a lot of data on boil-off, just from flying Centaurs all the way to geosynchronous orbit, which doesn’t involve weeks, but it involves maybe half a day or so, which is plenty of time to get all the temperatures to stabilize at deep space levels,” Sowers said. “So you have to understand the heat transfer very well. Good models are very important.”

ULA experimented with different types of insulation and vapor cooling, which involves taking cold gas that boiled off of cryogenic fuel and blowing it on heat penetration points into the tanks.

“There are tricks to managing boil-off,” he said. “One of the tricks is that you never want to boil oxygen. You always want to boil hydrogen. So you size your propellant tanks and your propellant loads, assuming you’re going to have that extra hydrogen boil-off. Then what you can do is use the hydrogen to keep the oxygen cold to keep it from boiling.

“The amount of heat that you can reject by boiling off one kilogram of hydrogen is about five times what you would reject by boiling off one kilogram of oxygen. So those are some of the thermodynamic tricks,” Sowers said. “The way ULA accomplished that is by having a common bulkhead, so the hydrogen tank and the oxygen tank are in thermal contact. So hydrogen keeps the oxygen cold.”

ULA’s experiments showed it could get the hydrogen boil-off rate down to about 10 percent per year, based on thermodynamic models calibrated by data from flying older versions of the Centaur upper stage on Atlas V rockets, according to Sowers.

“In my mind, that kind of cemented the idea that distribution depots and things like that are very well in hand without having to have exotic cryocoolers, which tend to use a lot of power,” Sowers said. “It’s about efficiency. If you can do it passively, you don’t have to expend energy on cryocoolers.”

“We’re going to go to days, and then we’re going to go to weeks, and then we think it’s possible to take us to months,” Bruno said. “That’s a game changer.”

However, ULA’s corporate owners haven’t yet fully bought into this vision. Bruno said the Vulcan rocket and its supporting manufacturing and launch infrastructure cost between $5 billion and $7 billion to develop. ULA also plans to eventually recover and reuse BE-4 main engines from the Vulcan rocket, but that is still at least several years away.

But ULA is reportedly up for sale, and a well-capitalized buyer might find the company’s long-duration cryogenic upper stage more attractive and worth the investment.

“There’s a whole lot of missions that enables,” Bruno said. “So that’s a big step in capability, both for the United States and also commercially.”

ULA hasn’t given up on developing a long-lived cryogenic space tug Read More »