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Today — 25 July 2024Science – Ars Technica

A chemist explains the chemistry behind decaf coffee

25 July 2024 at 11:07
Close-up of coffee beans with roasted beans on table

Enlarge (credit: matusgajdos17 / 500px via Getty Images)

For many people, the aroma of freshly brewed coffee is the start of a great day. But caffeine can cause headaches and jitters in others. That’s why many people reach for a decaffeinated cup instead.

I’m a chemistry professor who has taught lectures on why chemicals dissolve in some liquids but not in others. The processes of decaffeination offer great real-life examples of these chemistry concepts. Even the best decaffeination method, however, does not remove all of the caffeine—about 7 milligrams of caffeine usually remain in an 8-ounce cup.

Producers decaffeinating their coffee want to remove the caffeine while retaining all—or at least most—of the other chemical aroma and flavor compounds. Decaffeination has a rich history, and now almost all coffee producers use one of three common methods.

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“Not a bluff”—NASA’s budget would shut down long-lived Chandra telescope

24 July 2024 at 21:50
Artist's illustration of the Chandra X-ray Observatory.

Enlarge / Artist's illustration of the Chandra X-ray Observatory. (credit: NASA/MSFC)

NASA launched the Chandra X-ray Observatory 25 years ago this week, opening a new eye on the Universe and giving astronomers vision into unimaginably violent cosmic environments like exploding stars and black holes. But Chandra's mission may soon end as NASA's science division faces a nearly billion-dollar budget shortfall.

NASA says it can no longer afford to fund Chandra at the levels it has since the telescope launched in 1999. The agency has a diminished budget for science missions this year, and the reductions may continue next year due to government spending caps in a deal reached between Congress and the Biden administration last year to suspend the federal debt ceiling.

Congress and the White House have prioritized funding for NASA's human spaceflight programs, primarily the rockets, spacecraft, landers, spacesuits, and rovers needed for the Artemis program to return astronauts to the Moon. Meanwhile, the funding level for NASA's science mission directorate has dropped.

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Yesterday — 24 July 2024Science – Ars Technica

Diamond Shruumz candies suspected of causing second death, FDA reports

By: Beth Mole
24 July 2024 at 21:14
Diamond Shruumz candies suspected of causing second death, FDA reports

Enlarge (credit: Diamond Shruumz)

Authorities have identified a second death that may have been caused by Diamond Shruumz microdosing candies, which are under investigation for causing a nationwide rash of severe illnesses involving seizures, and the need for intubation and intensive care.

In an update on Tuesday, the Food and Drug Administration reported that the total number of illnesses linked to the brand's candies has risen to 74 across 28 states. Of the 74 people sickened, 62 sought medical care, and 38 were admitted to a hospital. There are two potentially associated deaths that are now under investigation. The counts are up from 69 cases and 36 hospitalizations, with one potentially linked death reported in an update last week.

The FDA announced its investigation into Diamond Shruumz products on June 7, when there had been just eight cases reported from four states. The federal investigation—led by the FDA and the Centers for Disease Control and Prevention, with help from America’s Poison Centers and state and local partners—followed warnings from Arizona poison control officials.

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Webb directly images giant exoplanet that isn’t where it should be

24 July 2024 at 20:28
A dark background with read and blue images embedded in it, both showing a single object near an area marked with an asterisk.

Enlarge / Image of Epsilon Indi A at two wavelengths, with the position of its host star indicated by an asterisk. (credit: T. Müller (MPIA/HdA), E. Matthews (MPIA))

We have a couple of techniques that allow us to infer the presence of an exoplanet based on its effects on the light coming from its host star. But there's an alternative approach that sometimes works: image them directly. It's much more limited, since the planet has to be pretty big and orbiting far away enough from its star to avoid having light coming from the planet swamped by the far more intense starlight.

Still, it has been done. Massive exoplanets have been captured relatively shortly after their formation, when the heat generated by the collapse of material into the planet causes them to glow in the infrared. But the Webb telescope is far more sensitive than any infrared observatory we've ever built, and it has managed to image a relatively nearby exoplanet that's roughly as old as the ones in our Solar System.

Looking directly at a planet

What do you need to directly image a planet that's orbiting a star light-years away? The first thing is a bit of hardware called a coronagraph attached to your telescope. This is responsible for blocking the light from the star the planet is orbiting; without it, that light will swamp any other sources in the exosolar system. Even with a good coronagraph, you need the planets to be orbiting at a significant distance from the star so that they're cleanly separated from the signal being blocked by the coronagraph.

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Woman who went on the lam with untreated TB is now cured

By: Beth Mole
24 July 2024 at 15:01
Scanning electron micrograph of <em>Mycobacterium tuberculosis</em> bacteria, which cause TB.

Scanning electron micrograph of Mycobacterium tuberculosis bacteria, which cause TB. (credit: National Institute of Allergy and Infectious Diseases)

"She's cured!"

Health officials in Washington state are celebrating the clean bill of health for one particularly notable resident: the woman who refused to isolate and get treatment for her active case of infectious tuberculosis for over a year. She even spent around three months on the lam, dodging police as they tried to execute a civil arrest warrant. During her time as a fugitive, police memorably reported that she took a city bus to go to a casino.

The woman, identified only as V.N. in court documents, had court orders to get treatment for her tuberculosis infection beginning in January of 2022. She refused to comply as the court renewed the orders on a monthly basis and held at least 17 hearings on the matter. The judge in her case issued an arrest warrant in March of 2023, but V.N. evaded law enforcement. She was finally arrested in June of last year and spent 23 days getting court-ordered treatment behind bars before being released with conditions.

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Want to cook like a Neanderthal? Archaeologists are learning the secrets

A scientist sits cross legged and defeathers one of the birds.

Enlarge / A scientist defeathers one of the birds used in hands-on experiments to replicate Neanderthal butchering and cooking methods. (credit: Mariana Nabais)

Archaeologists seeking to learn more about how Neanderthals prepared and cooked their food conducted a series of hands-on experiments with small fowl using flint flakes for butchering. They found that the flint flakes were surprisingly effective for butchering the birds, according to their new paper published in the journal Frontiers in Environmental Archaeology. They also concluded that roasting the birds damages the bones to such an extent that it's unlikely they would be preserved in the archaeological record.

According to the authors, Neanderthals were able to thrive for over 200,000 years across a broad range of geographical regions, so naturally archaeologists are interested in how they sustained themselves. There has been research into their killing and hunting of large game. Neanderthals were expert hunters known to kill bears and other carnivores. A pair of lion fibula from the Middle Paleolithic found in eastern Iberia with cut marks indicates the lion was butchered, while other lion bones found in Southwestern France from the same period had cut marks indicative of skinning.

And as we reported just last year, researchers found evidence of what might be the earliest example of lion hunting yet known, based on a close forensic analysis of a cave lion skeleton showing evidence of injury by a wooden spear some 48,000 years ago.

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Before yesterdayScience – Ars Technica

Appeals Court denies stay to states trying to block EPA’s carbon limits

23 July 2024 at 19:34
Cooling towers emitting steam, viewed from above.

Enlarge (credit: Bernhardt Lang)

On Friday, the US Court of Appeals for the DC Circuit denied a request to put a hold on recently formulated rules that would limit carbon emissions made by fossil fuel power plants. The request, made as part of a case that sees 25 states squaring off against the EPA, would have put the federal government's plan on hold while the case continued. Instead, the EPA will be allowed to continue the process of putting its rules into effect, and the larger case will be heard under an accelerated schedule.

Here we go again

The EPA's efforts to regulate carbon emissions from power plants go back all the way to the second Bush administration, when a group of states successfully sued the EPA to force it to regulate greenhouse gas emissions. This led to a formal endangerment finding regarding greenhouse gases during the Obama administration, something that remained unchallenged even during Donald Trump's term in office.

Obama tried to regulate emissions through the Clean Power Plan, but his second term came to an end before this plan had cleared court hurdles, allowing the Trump administration to formulate a replacement that did far less than the Clean Power Plan. This took place against a backdrop of accelerated displacement of coal by natural gas and renewables that had already surpassed the changes envisioned under the Clean Power Plan.

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SpaceX just stomped the competition for a new contract—that’s not great

23 July 2024 at 16:53
A rocket sits on a launch pad during a purple- and gold-streaked dawn.

Enlarge / With Dragon and Falcon, SpaceX has become an essential contractor for NASA. (credit: SpaceX)

There is an emerging truth about NASA's push toward commercial contracts that is increasingly difficult to escape: Companies not named SpaceX are struggling with NASA's approach of awarding firm, fixed-price contracts for space services.

This belief is underscored by the recent award of an $843 million contract to SpaceX for a heavily modified Dragon spacecraft that will be used to deorbit the International Space Station by 2030.

The recently released source selection statement for the "US Deorbit Vehicle" contract, a process led by NASA head of space operations Ken Bowersox, reveals that the competition was a total stomp. SpaceX faced just a single serious competitor in this process, Northrop Grumman. And in all three categories—price, mission suitability, and past performance—SpaceX significantly outclassed Northrop.

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A mid-September test flight of Vulcan could permit a military launch this year

23 July 2024 at 00:18
A top-down view of United Launch Alliance's first Vulcan rocket before its liftoff in January.

Enlarge / A top-down view of United Launch Alliance's first Vulcan rocket before its liftoff in January. (credit: United Launch Alliance)

United Launch Alliance is targeting September 16 for the second test flight of the new Vulcan rocket, and a flawless mission could finally set the stage for the first Vulcan launch for the US military by the end of the year.

The US Space Force has contracted ULA's Vulcan rocket to launch the majority of the military's space missions over the next few years. Pentagon officials are eager for Vulcan to get flying so they can start checking off a backlog of 25 military space missions the Space Force wants to launch by the end of 2027.

By any measure, the first Vulcan launch in January was a resounding success. On its debut flight, the new rocket delivered a commercial lunar lander to an on-target orbit. The next Vulcan mission, which ULA calls Cert-2, will be the rocket's second certification flight. The Space Force requires ULA to complete two successful flights of the Vulcan rocket before entrusting it to launch national security satellites.

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Human bird flu cases tick up; second Colorado poultry farm reports spread

By: Beth Mole
22 July 2024 at 22:22
Human bird flu cases tick up; second Colorado poultry farm reports spread

Enlarge (credit: Getty | David Paul Morris)

A second Colorado poultry farm has reported a case of bird flu in a worker, marking the state's seventh human case this month amid the ongoing outbreak among dairy cows.

Colorado health officials said the seventh case is, for now, a presumptive positive. That means that the person has tested positive at the state level while confirmatory testing is being carried out at the Centers for Disease Control and Prevention.

The presumptive positive worker was at a poultry facility in the state's northeastern Weld County. In recent weeks, six workers at another poultry farm in Weld also tested positive for bird flu. In that facility, a commercial egg layer operation with about 1.8 million birds, workers were infected as they culled chickens known to be infected with the highly pathogenic avian influenza. Genetic testing of the virus in the birds and the workers indicated that they were infected with a strain of H5N1 closely related to the virus found spreading in dairy cattle and to dairy farm workers.

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Model mixes AI and physics to do global forecasts

22 July 2024 at 17:45
Image of a dark blue flattened projection of the Earth, with lighter blue areas showing the circulation of the atmosphere.

Enlarge / Image of some of the atmospheric circulation seen during NeuralGCM runs. (credit: Google)

Right now, the world's best weather forecast model is a General Circulation Model, or GCM, put together by the European Center for Medium-Range Weather Forecasts. A GCM is in part based on code that calculates the physics of various atmospheric processes that we understand well. For a lot of the rest, GCMs rely on what's termed "parameterization," which attempts to use empirically determined relationships to approximate what's going on with processes where we don't fully understand the physics.

Lately, GCMs have faced some competition from machine-learning techniques, which train AI systems to recognize patterns in meteorological data and use those to predict the conditions that will result over the next few days. Their forecasts, however, tend to get a bit vague after more than a few days and can't deal with the sort of long-term factors that need to be considered when GCMs are used to study climate change.

On Monday, a team from Google's AI group and the European Centre for Medium-Range Weather Forecasts are announcing NeuralGCM, a system that mixes physics-based atmospheric circulation with AI parameterization of other meteorological influences. Neural GCM is computationally efficient and performs very well in weather forecast benchmarks. Strikingly, it can also produce reasonable-looking output for runs that cover decades, potentially allowing it to address some climate-relevant questions. While it can't handle a lot of what we use climate models for, there are some obvious routes for potential improvements.

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The Falcon 9 rocket may return to flight as soon as Tuesday night

22 July 2024 at 13:32
File photo of a Falcon 9 launch on May 6 from Cape Canaveral Space Force Station, Florida.

Enlarge / File photo of a Falcon 9 launch on May 6 from Cape Canaveral Space Force Station, Florida. (credit: SpaceX)

It was only about 10 days ago that the Falcon 9 rocket's upper stage failed in flight, preventing the rocket from delivering its 20 Starlink satellites into a proper orbit. Because they were released lower than expected—about 135 km above the Earth's surface and subject to atmospheric drag—these satellites ultimately reentered the planet's atmosphere and burnt up.

Typically, after a launch failure, a rocket will be sidelined for months while engineers and technicians comb over the available data and debris to identify a cause, perform tests, and institute a fix.

However, according to multiple sources, SpaceX was ready to launch the Falcon 9 rocket as soon as late last week. Currently, the company has a launch opportunity for no earlier than 12:14 am ET (04:14 UTC) on Wednesday for its Starlink 10-4 mission.

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We’re building nuclear spaceships again—this time for real 

22 July 2024 at 11:00
Artist concept of the Demonstration for Rocket to Agile Cislunar Operations (DRACO) spacecraft.

Enlarge / Artist concept of the Demonstration for Rocket to Agile Cislunar Operations (DRACO) spacecraft. (credit: DARPA)

Phoebus 2A, the most powerful space nuclear reactor ever made, was fired up at Nevada Test Site on June 26, 1968. The test lasted 750 seconds and confirmed it could carry first humans to Mars. But Phoebus 2A did not take anyone to Mars. It was too large, it cost too much, and it didn’t mesh with Nixon’s idea that we had no business going anywhere further than low-Earth orbit.

But it wasn’t NASA that first called for rockets with nuclear engines. It was the military that wanted to use them for intercontinental ballistic missiles. And now, the military wants them again.

Nuclear-powered ICBMs

The work on nuclear thermal rockets (NTRs) started with the Rover program initiated by the US Air Force in the mid-1950s. The concept was simple on paper. Take tanks of liquid hydrogen and use turbopumps to feed this hydrogen through a nuclear reactor core to heat it up to very high temperatures and expel it through the nozzle to generate thrust. Instead of causing the gas to heat and expand by burning it in a combustion chamber, the gas was heated by coming into contact with a nuclear reactor.

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Will burying biomass underground curb climate change?

20 July 2024 at 11:20
Will burying biomass underground curb climate change?

(credit: TEEIC)

On April 11, a small company called Graphyte began pumping out beige bricks, somewhat the consistency of particle board, from its new plant in Pine Bluff, Arkansas. The bricks don’t look like much, but they come with a lofty goal: to help stop climate change.

Graphyte, a startup backed by billionaire Bill Gates’ Breakthrough Energy Ventures, will bury its bricks deep underground, trapping carbon there. The company bills it as the largest carbon dioxide removal project in the world.

Scientists have long warned of the dire threat posed by global warming. It’s gotten so bad though that the long-sought mitigation, cutting carbon dioxide emissions from every sector of the economy, might not be enough of a fix. To stave off the worst—including large swaths of the Earth exposed to severe heat waves, water scarcity, and crop failures—some experts say there is a deep need to remove previously emitted carbon, too. And that can be done anywhere on Earth—even in places not known for climate-friendly policies, like Arkansas.

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Mini-Neptune turned out to be a frozen super-Earth

20 July 2024 at 10:00
Image of three planets on a black background, with the two on the left being mostly white, indicating an icy composition. The one on the right is much smaller, and represents Earth.

Enlarge / Renditions of a possible composition of LHS 1140 b, with a patch of ocean on the side facing its host star. Earth is included at right for scale. (credit: BENOIT GOUGEON, UNIVERSITÉ DE MONTRÉAL)

Of all the potential super-Earths—terrestrial exoplanets more massive than Earth—out there, an exoplanet orbiting a star only 40 light-years away from us in the constellation Cetus might be the most similar to have been found so far.

Exoplanet LHS 1140 b was assumed to be a mini-Neptune when it was first discovered by NASA’s James Webb Space Telescope toward the end of 2023. After analyzing data from those observations, a team of researchers, led by astronomer Charles Cadieux, of Université de Montréal, suggest that LHS 1140 b is more likely to be a super-Earth.

If this planet is an alternate version of our own, its relative proximity to its cool red dwarf star means it would most likely be a gargantuan snowball or a mostly frozen body with a substellar (region closest to its star) ocean that makes it look like a cosmic eyeball. It is now thought to be the exoplanet with the best chance for liquid water on its surface, and so might even be habitable.

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Armada to Apophis—scientists recycle old ideas for rare asteroid encounter

20 July 2024 at 00:26
This artist's concept shows the possible appearance of ESA's RAMSES spacecraft, which will release two small CubeSats for additional observations at Apophis.

Enlarge / This artist's concept shows the possible appearance of ESA's RAMSES spacecraft, which will release two small CubeSats for additional observations at Apophis. (credit: ESA-Science Office)

For nearly 20 years, scientists have known an asteroid named Apophis will pass unusually close to Earth on Friday, April 13, 2029. But most officials at the world's space agencies stopped paying much attention when updated measurements ruled out the chance Apophis will impact Earth any time soon.

Now, Apophis is again on the agenda, but this time as a science opportunity, not as a threat. The problem is, there's not much time to design, build, and launch a spacecraft to get into position near Apophis in less than five years. The good news is there are designs, and in some cases, existing spacecraft, that governments can repurpose for missions to Apophis, a rocky asteroid about the size of three football fields.

Scientists discovered Apophis in 2004, and the first measurements of its orbit indicated there was a small chance it could strike Earth in 2029 or in 2036. Using more detailed radar observations of Apophis, scientists in 2021 ruled out any danger to Earth for at least the next 100 years.

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Illegal drug found in Diamond Shruumz candies linked to severe illnesses

By: Beth Mole
19 July 2024 at 17:59
Illegal drug found in Diamond Shruumz candies linked to severe illnesses

Enlarge (credit: Diamond Shruumz)

Newly released testing data of Diamond Shruumz-brand gummies purchased in 2023 identified the presence of psilocin, a hallucinogenic drug closely related to the magic-mushroom drug psilocybin that is classified as a Schedule I drug, alongside psilocybin, heroin, and LSD.

The finding comes as Diamond Shruumz's current line of gummies, chocolates, and candy cones is being recalled and are under active investigation in connection to a nationwide rash of severe illnesses, which have involved seizures, intubation, and intensive care. As of the latest update on July 15, 69 people in 28 states have been sickened after eating a Diamond Shruumz product. Sixty of the 69 sought medical care, 36 were hospitalized, and there is one potentially associated death under investigation.

The new finding, published by researchers at the University of Virginia, of psilocin in the products adds to growing concern about psychedelic mushroom candies generally. Although the candies are marketed as being legal, they have often been found to contain various undisclosed illegal drugs or gray market synthetic versions of drugs, as well as dangerous adulterants and contaminants.

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Coal-filled trains are likely sending people to the hospital

19 July 2024 at 14:34
a long line of open-top rail cars filled with coal against a parched, scrub filled hill.

Enlarge (credit: Bloomberg Creative Photos)

Although US coal consumption has fallen dramatically since 2005, the country still consumes millions of tons a year, and exports tons more—much of it transported by train. Now, new research shows that these trains can affect the health of people living near where they pass.

The study found that residents living near railroad tracks likely have higher premature mortality rates due to air pollutants released during the passage of uncovered coal trains. The analysis of the San Francisco Bay Area cities of Oakland, Richmond, and Berkeley shows that increases in air pollutants such as small particulate matter (PM 2.5) are also associated with increases in asthma-related episodes and hospital admissions.

"This has never been studied in the world. There's been a couple studies trying to measure just the air pollution, usually in rural areas, but this was the first to both measure air pollution and trains in an urban setting," said Bart Ostro, author of the study and an epidemiologist at the University of California, Davis.

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Rocket Report: Firefly’s CEO steps down; Artemis II core stage leaves factory

19 July 2024 at 11:00
The core stage for NASA's second Space Launch System rocket rolls aboard a barge that will take it from New Orleans to Kennedy Space Center in Florida.

Enlarge / The core stage for NASA's second Space Launch System rocket rolls aboard a barge that will take it from New Orleans to Kennedy Space Center in Florida. (credit: NASA)

Welcome to Edition 7.03 of the Rocket Report! One week ago, SpaceX suffered a rare failure of its workhorse Falcon 9 rocket. In fact, it was the first time the latest version of the Falcon 9, known as the Block 5, has ever failed on its prime mission after nearly 300 launches. The world's launch pads have been silent since the grounding of the Falcon 9 fleet after last week's failure. This isn't surprising, but it's noteworthy. After all, the Falcon 9 has flown more this year than all of the world's other rockets combined and is fundamental to much of what the world does in space.

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

Astra finally goes private, again. A long-simmering deal for Astra's founders to take the company private has been finalized, the company announced Thursday, capping the rocket launch company’s descent from blank-check darling to delisting in three years, Bloomberg reports. The launch company's valuation peaked at $3.9 billion in 2021, the year it went public, and was worth about $12.2 million at the end of March, according to data compiled by Bloomberg. Astra's chief executive officer, Chris Kemp, and chief technology officer, Adam London, founded the company in 2016 with the goal of essentially commoditizing launch services for small satellites. But Astra's rockets failed to deliver and fell short of orbit five times in seven tries.

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