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In the Southwest, solar panels can help both photovoltaics and crops

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Cultivation in a harsh climate

Solar arrays can shade crops from sun while moisture cools the panels to increase their productivity.

Volunteers with the National Renewable Energy Laboratory work at Jack’s Solar Garden in Longmont, Colorado. Credit: Bryan Bechtold/NREL

This article originally appeared on Inside Climate News, a nonprofit, non-partisan news organization that covers climate, energy, and the environment. Sign up for their newsletter here.

“We were getting basil leaves the size of your palm,” University of Arizona researcher Greg Barron-Gafford said, describing some of the benefits he and his team have seen farming under solar panels in the Tucson desert.

For 12 years, Barron-Gafford has been investigating agrivoltaics, the integration of solar arrays into working farmland. This practice involves growing crops or other vegetation, such as pollinator-friendly plants, under solar panels, and sometimes grazing livestock in this greenery. Though a relatively new concept, at least 604 agrivoltaic sites have popped up across the United States, according to OpenEI.

Researchers like Barron-Gafford think that, in addition to generating carbon-free electricity, agrivoltaics could offer a ray of hope for agriculture in an increasingly hotter and drier Southwest, as the shade created by these systems has been found to decrease irrigation needs and eliminate heat stress on crops. Plus, the cooling effects of growing plants under solar arrays can actually make the panels work better.

But challenges remain, including some farmers’ attitudes about the practice and funding difficulties.

Overcoming a climate conundrum

While renewable electricity from sources like solar panels is one of the most frequently touted energy solutions to help reduce the carbon pollution that’s driving climate change, the warming climate itself is making it harder for solar arrays to do their job, Barron-Gafford said. An optimal functioning temperature for panels is around 75° Fahrenheit, he explained. Beyond that, any temperature increase reduces the photovoltaic cells’ efficiency.

“You can quickly see how this solution for our changing climate of switching to more renewable energy is itself sensitive to the changing climate,” he said.

This problem is especially pertinent in the Southwest, where historically hot temperatures are steadily increasing. Tucson, for instance, saw a record-breaking 112 days of triple-digit heat in 2024, according to National Weather Service Data, and the US Environmental Protection Agency reports that every part of the Southwest experienced higher average temperatures between 2000 and 2023 compared to the long-term average from 1895 to 2023.

However, planting vegetation under solar panels—as opposed to the more traditional method of siting solar arrays on somewhat barren land—can help cool them. In one set of experiments, Barron-Gafford’s team found that planting cilantro, tomatoes and peppers under solar arrays reduced the panels’ surface temperature by around 18 degrees Fahrenheit. That’s because plants release moisture into the air during their respiration process, in which they exchange oxygen for carbon dioxide.

“This invisible power of water coming out of plants was actually cooling down the solar panels,” Barron-Gafford said.

Throwing shade

While Barron-Gafford said some laughed him off when he first proposed the idea of growing crops in the shade of solar panels, this added sun shield can actually help them grow better, especially in the Southwest, where many backyard gardeners already employ shade cloths to protect their gardens from the blazing heat.

“Many people don’t understand that in Colorado and much of the West, most plants get far too much sunlight,” said Byron Kominek, owner/manager of Jack’s Solar Garden in Boulder County, Colorado, which began implementing agrivoltaics in 2020. “Having some shade is a benefit to them.”

Jack’s Solar Garden has integrated 3,276 solar panels over about four acres of farmland, growing crops like greens and tomatoes. Meg Caley with Sprout City Farms, a nonprofit that helps with farming duties at Jack’s Solar Garden, said they’ve been able to produce Swiss chard “the size of your torso.”

“The greens just get huge,” she said. “You have to chop them up to fit them in your refrigerator.”

She added that the shade seems to improve the flavor of the vegetables and prevents them from bolting, when plants prematurely produce flowers and seeds, diverting energy away from leaf or root growth.

“Plants when they’re stressed out can have more of a bitter flavor,” she explained. “So the arugula that we grow is not as bitter or spicy. It’s sweeter. The spinach is sweeter too.”

Barron-Gafford and his team are seeing the same thing in Arizona, where they grow a variety of produce like beans, artichokes, potatoes, kale, and basil.

“We’ve grown 30-plus different types of things across different wet winters and dry winters and exceptionally hot summers, dry summers, average or close to average summers,” he said of the solar-shaded crops. “And across everything we’ve done, we’ve seen equal or greater production down here in the Southwest, the dry land environments, where it really benefits to get some shade.”

As in Colorado, some of those crops are growing to epic proportions.

“We’ve made bok choy the size of a toddler,” Barron-Gafford said.

All that shade provides another important benefit in a drought-stricken Southwest—lower water requirements for crops. Because less direct sunlight is hitting the ground, it decreases the evaporation rate, which means water stays in the soil longer after irrigation. Barron-Gafford and his team have been running experiments for the last seven or so years to see how this plays out with different crops in an agrivoltaic setting.

“What is the evaporation rate under something that’s big and bushy like a bean or potato plant versus something thinner above ground, like a carrot?” is one of the questions Barron-Gafford said they have tried to answer. “For the most part, I would say that we are able to cut back our irrigation by more than half.”

They are partnering with Jack’s Solar Farm on water research in Colorado and have so far found similar results there.

This shade has another benefit in a warming world—respite for farmworkers. Heat-related illnesses are a growing concern for people who work outside, and one recent study predicted climate change will quadruple U.S. outdoor workers’ exposure to extreme heat conditions by 2065.

But with solar arrays in the fields, “if you really carefully plan out your day, you can work in the shade,” a factor that can help increase worker safety on hot days, Caley said.

The AgriSolar Clearinghouse performed skin temperature readings under solar panels and full sun at a number of sites across the United States, finding a skin temperature decrease of 15.3° in Boulder and 20.8° in Phoenix.

“I don’t know what the future holds”

Despite the benefits of agrivoltaics, the up-front cost of purchasing a solar array remains a barrier to farmers.

“Once people see the potential of agrivoltaics, you run into the next challenge, which is how do you fund someone getting into this on their site?” Barron-Gafford said. “And depending on the amount of capital or access to capital that a farmer has, you’re going to get a wildly different answer.”

While expenses are dependent on the size of the installation, a 25-kilowatt system would require an upfront cost of around $67,750, according to AgriSolar Clearinghouse. For comparison, the median size of a residential solar array in 2018 was around 6 kW, the organization stated, which would cost around $16,260 to install.

Kominek said the total initial cost of implementing a 1.2 megawatt capacity agrivoltaics setup on his farm in Colorado was around $2 million, but that the investment has paid off. In addition to the revenue he earns from farming, all of the energy produced by the arrays is sold to clients in the community through a local utility company, earning the farm money.

The Rural Energy for America program has been one resource for farmers interested in agrivoltaics, offering loans and grants to help install solar. However, it’s unclear how this program will move forward amid current federal spending cuts.

Meanwhile, some of the federal grant programs that Barron-Gafford has relied on have suddenly come to a halt, he said, putting his research in danger. But, as federal support dries up, some states are charging on with their own funding opportunities to develop farm field solar projects. For instance, Colorado’s Agrivoltaics Research and Demonstration Grant offers money for demonstrations of agrivoltaics, research projects, and outreach campaigns.

There are other challenges as well. Caley, for instance, said farming around solar panels is akin to working in an “obstacle course.” She and her team, who mostly work manually, have found ways to work around them by being aware of their surroundings so that they don’t accidentally collide with the panels or strike them with their tools. This job is also made easier since Kominek invested between $80,000 and $100,000 to elevate his farm’s panels, which better allows animals, taller crops and farming equipment to operate beneath.

Still, a 2025 University of Arizona study that interviewed farmers and government officials in Pinal County, Arizona, found that a number of them questioned agrivoltaics’ compatibility with large-scale agriculture.

“I think it’s a great idea, but the only thing … it wouldn’t be cost-efficient … everything now with labor and cost of everything, fuel, tractors, it almost has to be super big … to do as much with as least amount of people as possible,” one farmer stated.

Many farmers are also leery of solar, worrying that agrivoltaics could take working farmland out of use, affect their current operations or deteriorate soils.

Those fears have been amplified by larger utility-scale initiatives, like Ohio’s planned Oak Run Solar Project, an 800 megawatt project that will include 300 megawatts of battery storage, 4,000 acres of crops and 1,000 grazing sheep in what will be the country’s largest agrivoltaics endeavor to date. Opponents of the project worry about its visual impacts and the potential loss of farmland.

An American Farmland Trust survey found that Colorado farmers would prefer that utility-scale solar projects be sited on less productive or underutilized farmland rather than on highly productive or actively farmed land. They also expressed concern for the potential negative impact that solar projects could have on farm productivity and the health of the land, including soil quality.

Some farmers also worry that the solar panels could leach metals into the ground, contaminating their crops, Barron-Gafford said. But while agrivoltaic systems are put together in a way that makes that highly unlikely, there’s no reason not to add soil sampling studies into the work they’re doing to reassure farmers, he added.

And agrivoltaics advocates say that the practice could actually improve soil health by reducing erosion, increasing the amount of organic matter and enhancing soil biology with cooler, moister conditions.

“I wish more people spent time listening to the folks on the ground and the folks experiencing these transitions,” Barron-Gafford added. “Because you understand more that way in terms of what their motivations or concerns actually are.”

“We don’t have to choose”

While Caley understands farmers’ concerns, she sees agrivoltaics as a way for them to keep agricultural land in production while also benefiting from solar electricity.

“The tension in a lot of communities seems to be that people don’t want to see agricultural land taken out of production in order to bring a solar farm in,” she said. “The idea here is that we don’t have to choose. We can have both.”

Kominek encourages people to envision what our landscapes and climate will look like in the next 20 to 30 years, adding that in his part of Colorado, it only stands to get hotter and drier, making agrivoltaics a smart solution for farming and clean energy production.

“Communities around the world need to figure out what changes they need to make now to help people adapt to what our climates and landscapes will be in the future,” he said. “Agrivoltaics is a climate adaptation tool that will benefit any community where such systems are built as the decades pass.”

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It’s hunting season in orbit as Russia’s killer satellites mystify skywatchers

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“Once more, we play our dangerous game—a game of chess—against our old adversary.”

In this pool photograph distributed by the Russian state media agency Sputnik, Russia’s President Vladimir Putin gives a speech during the Victory Day military parade at Red Square in central Moscow on May 9, 2025. Credit: Yacheslav Prokofyev/Pool/AFP via Getty Images

Russia is a waning space power, but President Vladimir Putin has made sure he still has a saber to rattle in orbit.

This has become more evident in recent weeks, when we saw a pair of rocket launches carrying top-secret military payloads, the release of a mysterious object from a Russian mothership in orbit, and a sequence of complex formation-flying maneuvers with a trio of satellites nearly 400 miles up.

In isolation, each of these things would catch the attention of Western analysts. Taken together, the frenzy of maneuvers represents one of the most significant surges in Russian military space activity since the end of the Cold War. What’s more, all of this is happening as Russia lags further behind the United States and China in everything from rockets to satellite manufacturing. Russian efforts to develop a reusable rocket, field a new human-rated spacecraft to replace the venerable Soyuz, and launch a megaconstellation akin to SpaceX’s Starlink are going nowhere fast.

Russia has completed just eight launches to orbit so far this year, compared to 101 orbital attempts by US launch providers and 36 from China. This puts Russia on pace for the fewest number of orbital launch attempts since 1961, the year Soviet citizen Yuri Gagarin became the first person to fly in space.

For the better part of three decades, Russia’s space program could rely on money from Western governments and commercial companies to build rockets, launch satellites, and ferry astronauts to and from the International Space Station. The money tap dried up after Russia’s invasion of Ukraine. Russia also lost access to Ukrainian-made components to go into their launch vehicles and satellites.

Chasing a Keyhole

Amid this retrenchment, Russia is targeting what’s left of its capacity for innovation in space toward pestering the US military. US intelligence officials last year said they believed Russia was pursuing a project to place a nuclear weapon in space. The detonation of a nuclear bomb in orbit could muck up the space environment for years, indiscriminately disabling countless satellites, whether they’re military or civilian.

Russia denied that it planned to launch a satellite with a nuclear weapon, but the country’s representative in the United Nations vetoed a Security Council resolution last year that would have reaffirmed a nearly 50-year-old ban on placing weapons of mass destruction into orbit.

While Russia hasn’t actually put a nuclear bomb into orbit yet, it’s making progress in fielding other kinds of anti-satellite systems. Russia destroyed one of its own satellites with a ground-launched missile in 2021, and high above us today, Russian spacecraft are stalking American spy satellites and keeping US military officials on their toes with a rapid march toward weaponizing space.

The world’s two other space powers, the United States and China, are developing their own “counter-space” weapons. But the US and Chinese militaries have largely focused on using their growing fleets of satellites as force multipliers in the terrestrial domain, enabling precision strikes, high-speed communications, and targeting for air, land, and naval forces. That is starting to change, with US Space Force commanders now openly discussing their own ambitions for offensive and defensive counter-space weapons.

Three of Russia’s eight orbital launches this year have carried payloads that could be categorized as potential anti-satellite weapons, or at least prototypes testing novel technologies that could lead to one. (For context, three of Russia’s other launches this year have gone to the International Space Station, and two launched conventional military communications or navigation satellites.)

One of these mystery payloads launched on May 23, when a Soyuz rocket boosted a satellite into a nearly 300-mile-high orbit perfectly aligned with the path of a US spy satellite owned by the National Reconnaissance Office. The new Russian satellite, designated Kosmos 2588, launched into the same orbital plane as an American satellite known to the public as USA 338, which is widely believed to be a bus-sized KH-11, or Keyhole-class, optical surveillance satellite.

A conceptual drawing of a KH-11 spy satellite, with internal views, based on likely design similarities to NASA’s Hubble Space Telescope. Credit: Giuseppe De Chiara/CC BY-SA 3.0

The governments of Russia and the United States use the Kosmos and USA monikers as cover names for their military satellites.

While their exact design and capabilities are classified, Keyhole satellites are believed to provide the sharpest images of any spy satellite in orbit. They monitor airfields, naval ports, missile plants, and other strategic sites across the globe. In the zeitgeist of geopolitics, China, Russia, Iran, and North Korea are the likeliest targets for the NRO’s Keyhole satellites. To put it succinctly, Keyhole satellites are some of the US government’s most prized assets in space.

Therefore, it’s not surprising to assume a potential military adversary might want to learn more about them or be in a position to disable or destroy them in the event of war.

Orbital ballet

A quick refresher on orbital mechanics is necessary here. Satellites orbit the Earth in flat planes fixed in inertial space. It’s not a perfect interpretation, but it’s easiest to understand this concept by imagining the background of stars in the sky as a reference map. In the short term, the position of a satellite’s orbit will remain unchanged on this reference map without any perturbation. For something in low-Earth orbit, Earth’s rotation presents a different part of the world to the satellite each time it loops around the planet.

It takes a lot of fuel to make changes to a satellite’s orbital plane, so if you want to send a satellite to rendezvous with another spacecraft already in orbit, it’s best to wait until our planet’s rotation brings the launch site directly under the orbital plane of the target. This happens twice per day for a satellite in low-Earth orbit.

That’s exactly what Russia is doing with a military program named Nivelir. In English, Nivelir translates to “dumpy level”—an optical instrument used by builders and surveyors.

The launch of Kosmos 2588 in May was precisely timed for the moment Earth’s rotation brought the Plesetsk Cosmodrome in northern Russia underneath the orbital plane of the NRO’s USA 338 Keyhole satellite. Launches to the ISS follow the same roadmap, with crew and cargo vehicles lifting off at exactly the right time—to the second—to intersect with the space station’s orbital plane.

Since 2019, Russia has launched four satellites into bespoke orbits to shadow NRO spy satellites. None of these Russian Nivelir spacecraft have gotten close to their NRO counterparts. The satellites have routinely passed dozens of miles from one another, but the similarities in their orbits would allow Russia’s spacecraft to get a lot closer—and theoretically make physical contact with the American satellite. The Nivelir satellites have even maneuvered to keep up with their NRO targets when US ground controllers have made small adjustments to their orbits.

“This ensures that the orbital planes do not drift apart,” wrote Marco Langbroek, a Dutch archaeologist and university lecturer on space situational awareness. Langbroek runs a website cataloguing military space activity.

This is no accident

There’s reason to believe that the Russian satellites shadowing the NRO in orbit might be more than inspectors or stalkers. Just a couple of weeks ago, another Nivelir satellite named Kosmos 2558 released an unknown object into an orbit that closely mirrors that of an NRO spy satellite named USA 326.

We’ve seen this before. An older Nivelir satellite, Kosmos 2542, released a sub-satellite shortly after launching in 2019 into the same orbital plane as the NRO’s USA 245 satellite, likely a KH-11 platform similar to the USA 338 satellite now being shadowed by Kosmos 2588.

After making multiple passes near the USA 245 spacecraft, Kosmos 2542’s sub-satellite backed off and fired a mysterious projectile in 2020 at a speed fast enough to damage or destroy any target in its sights. US military officials interpreted this as a test of an anti-satellite weapon.

Now, another Russian satellite is behaving in the same way, with a mothership opening up to release a smaller object that could in turn reveal its own surprise inside like a Matryoshka nesting doll. This time, however, the doll is unnesting nearly three years after launch. With Kosmos 2542, this all unfolded within months of arriving in space.

The NRO’s USA 326 satellite launched in February 2022 aboard a SpaceX Falcon 9 rocket from Vandenberg Space Force Base, California. It is believed to be an advanced electro-optical reconnaissance satellite, although the circumstances of its launch suggest a design different from the NRO’s classic Keyhole spy satellites. Credit: SpaceX

In just the last several days, the smaller craft deployed by Kosmos 2558—designated “Object C”—lowered its altitude to reach an orbit in resonance with USA 326, bringing it within 60 miles (100 kilometers) of the NRO satellite every few days.

While US officials are worried about Russian anti-satellite weapons, or ASATs, the behavior of Russia’s Nivelir satellites is puzzling. It’s clear that Russia is deliberately launching these satellites to get close to American spy craft in orbit, a retired senior US military space official told Ars on background.

“If you’re going to launch a LEO [low-Earth orbit] satellite into the exact same plane as another satellite, you’re doing that on purpose,” said the official, who served in numerous leadership positions in the military’s space programs. “Inclination is one thing. We put a bunch of things into Sun-synchronous orbits, but you have a nearly boundless number of planes you can put those into—360 degrees—and then you can go down to probably the quarter-degree and still be differentiated as being a different plane. When you plane-match underneath that, you’re doing that on purpose.”

But why?

What’s not as obvious is why Russia is doing this. Lobbing an anti-satellite, or counter-space, weapon into the same orbital plane as its potential target ties Russia’s hands. Also, a preemptive strike on an American satellite worth $1 billion or more could be seen as an act of war.

“I find it strange that the Russians are doing that, that they’ve invested their rubles in a co-planar LEO counter-space kind of satellite,” the retired military official said. “And why do I say that? Because when you launch into that plane, you’re basically committed to that plane, which means you only have one potential target ever.”

A ground-based anti-satellite missile, like the one Russia tested against one of its own satellites in 2021, could strike any target in low-Earth orbit.

“So why invest in something that is so locked into a target once you put it up there, when you have the flexibility of a ground launch case that’s probably even cheaper?” this official told Ars. “I’d be advocating for more ground-launched ASATs if I really wanted the flexibility to go after new payloads, because this thing can never go after anything new.”

“The only way to look at it is that they’re sending us messages. You say, ‘Hey, I’m going to just annoy the hell out of you. I’m going to put something right on your tail,'” the official said. “And maybe there’s merit to that, and they like that. It doesn’t make sense from a cost-benefit or an operational flexibility perspective, if you think about it, to lock in on a single target.”

Nevertheless, Russia’s Nivelir satellites have shown they could fire a projectile at another spacecraft in orbit, so US officials don’t dismiss the threat. Slingshot Aerospace, a commercial satellite tracking and analytics firm, went straight to the point in its assessment: “Kosmos 2588 is thought to be a Nivelir military inspection satellite with a suspected kinetic weapon onboard.”

Langbroek agrees, writing that he is concerned that Russia might be positioning “dormant” anti-satellite weapons within striking distance of NRO spy platforms.

“To me, the long, ongoing shadowing of what are some of the most prized US military space assets, their KH-11 Advanced Enhanced Crystal high-resolution optical IMINT (imaging intelligence) satellites, is odd for ‘just’ an inspection mission,” Langbroek wrote.

American pilot Francis Gary Powers, second from right, in a Moscow courtroom during his trial on charges of espionage after his U-2 spy plane was shot down while working for the CIA. Credit: Pictorial Parade/Archive Photos/Getty Images

The US military’s ability to spy over vast swaths of Russian territory has been a thorn in Russia’s side since the height of the Cold War.

“They thought they had the edge and shot down Gary Powers,” the retired official said, referring to the Soviet Union’s shoot-down of an American U-2 spy plane in 1960. “They said, ‘We’re going to keep those Americans from spying on us.’ And then they turn around, and we’ve got spy satellites. They’ve always hated them since the 1960s, so I think there’s still this cultural thing out there: ‘That’s our nemesis. We hate those satellites. We’re just going to fight them.'”

Valley of the dolls

Meanwhile, the US Space Force and outside analysts are tracking a separate trio of Russian satellites engaged in a complex orbital dance with one another. These satellites, numbered Kosmos 2581, 2582, and 2583, launched together on a single rocket in February.

While these three spacecraft aren’t shadowing any US spy satellites, things got interesting when one of the satellites released an unidentified object in March in a similar way to how two of Russia’s Nivelir spacecraft have deployed their own sub-satellites.

Kosmos 2581 and 2582 came as close as 50 meters from one another while flying in tandem, according to an analysis by Bart Hendrickx published in the online journal The Space Review earlier this year. The other member of the trio, Kosmos 2583, released its sub-satellite and maneuvered around it for about a month, then raised its orbit to match that of Kosmos 2581.

Finally, in the last week of June, Kosmos 2582 joined them, and all three satellites began flying close to one another, according to Langbroek, who called the frenzy of activity one of the most complex rendezvous and proximity operations exercises Russia has conducted in decades.

Higher still, two more Russian satellites are up to something interesting after launching on June 19 on Russia’s most powerful rocket. After more than 30 years in development, this was the first flight of Russia’s Angara A5 rocket, with a real functioning military satellite onboard, following four prior test launches with dummy payloads.

The payload Russia’s military chose to launch on the Angara A5 is unusual. The rocket deployed its primary passenger, Kosmos 2589, into a peculiar orbit hugging the equator and ranging between approximately 20,000 (12,500 miles) and 51,000 kilometers (31,700 miles) in altitude.

In this orbit, Kosmos 2589 completes a lap around the Earth about once every 24 hours, giving the satellite a synchronicity that allows it to remain nearly fixed in the sky over the same geographic location. These kinds of geosynchronous, or GEO, orbits are usually circular, with a satellite maintaining the same altitude over the equator.

The orbits of Kosmos 2589 and its companion satellite, illustrated in green and purple, bring the two Russian spacecraft through the geostationary satellite belt twice per day. Credit: COMSPOC

But Kosmos 2589 is changing altitude throughout its day-long orbit. Twice per day, on the way up and back down, Kosmos 2589 briefly passes near a large number of US government and commercial satellites in more conventional geosynchronous orbits but then quickly departs the vicinity. At a minimum, this could give Russian officials the ability to capture close-up views of American spy satellites.

Then, a few days after Kosmos 2589 reached orbit last month, commercial tracking sensors detected a second object nearby. Sound familiar? This new object soon started raising its altitude, and Kosmos 2589 followed suit.

Aiming higher

Could this be the start of an effort to extend the reach of Russian inspectors or anti-satellite weapons into higher orbits after years of mysterious activity at lower altitudes?

Jim Shell, a former NRO project manager and scientist at Air Force Space Command, suggested the two satellites seem positioned to cooperate with one another. “Many interesting scenarios here such as ‘spotter shooter’ among others. Certainly something to keep eyes on!” Shell posted Saturday on X.

COMSPOC, a commercial space situational awareness company, said the unusual orbit of Kosmos 2589 and its companion put the Russian satellites in a position to, at a minimum, spy on Western satellites in geosynchronous orbit.

“This unique orbit, which crosses two key satellite regions daily, may aid in monitoring objects in both GEO and graveyard orbits,” COMSPOC wrote on X. “Its slight 1° inclination could also reduce collision risks. While the satellite’s mission remains unclear, its orbit suggests interesting potential roles.”

Historically, Russia’s military has placed less emphasis on operating in geosynchronous orbit than in low-Earth orbit or other unique perches in space. Due to their positions near the equator, geosynchronous orbits are harder to reach from Russian spaceports because of the country’s high latitude. But Russia’s potential adversaries, like the United States and Europe, rely heavily on geosynchronous satellites.

Other Russian satellites have flown near Western communications satellites in geosynchronous orbit, likely in an attempt to eavesdrop on radio transmissions.

“So it is interesting that they may be doing a GEO inspector,” the retired US military space official told Ars. “I would be curious if that’s what it is. We’ve got to watch. We’ve got to wait and see.”

If you’re a fan of spy techno-thrillers, this all might remind you of the plot from The Hunt for Red October, where a new state-of-the-art Russian submarine leaves its frigid port in Murmansk with orders to test a fictional silent propulsion system that could shake up the balance of power between the Soviet and American navies.

Just replace the unforgiving waters of the North Atlantic Ocean with an environment even more inhospitable: the vacuum of space.

A few minutes into the film, the submarine’s commander, Marko Ramius, played by Sean Connery, announces his orders to the crew. “Once more, we play our dangerous game, a game of chess, against our old adversary—the American Navy.”

Today, nearly 40 years removed from the Cold War, the old adversaries are now scheming against one another in space.

Photo of Stephen Clark

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.

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Mighty mitochondria: Cell powerhouses harnessed for healing

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rescuing suboptimal organs

Researchers hope a new technique can treat a variety of damaged organs.

James McCully was in the lab extracting tiny structures called mitochondria from cells when researchers on his team rushed in. They’d been operating on a pig heart and couldn’t get it pumping normally again.

McCully studies heart damage prevention at Boston Children’s Hospital and Harvard Medical School and was keenly interested in mitochondria. These power-producing organelles are particularly important for organs like the heart that have high energy needs. McCully had been wondering whether transplanting healthy mitochondria into injured hearts might help restore their function.

The pig’s heart was graying rapidly, so McCully decided to try it. He loaded a syringe with the extracted mitochondria and injected them directly into the heart. Before his eyes, it began beating normally, returning to its rosy hue.

Since that day almost 20 years ago, McCully and other researchers have replicated that success in pigs and other animals. Human transplantations followed, in babies who suffered complications from heart surgery—sparking a new field of research using mitochondria transplantation to treat damaged organs and disease. In the last five years, a widening array of scientists have begun exploring mitochondria transplantation for heart damage after cardiac arrest, brain damage following stroke, and damage to organs destined for transplantation.

This graphic depicts the basic steps and results of mitochondrial transplantation. Scientists think that donor mitochondria fuse with the recipient cells’ mitochondrial networks. Then they work to shrink the size of the infarct (the area of tissue dying from lack of blood and oxygen), among other effects. Scientists have studied such transplants in kidneys, livers, muscle, brains, hearts, and lungs. Credit: Knowable Magazine

Mitochondria are best known for producing usable energy for cells. But they also send molecular signals that help to keep the body in equilibrium and manage its immune and stress responses. Some types of cells may naturally donate healthy mitochondria to other cells in need, such as brain cells after a stroke, in a process called mitochondria transfer. So the idea that clinicians could boost this process by transplanting mitochondria to reinvigorate injured tissue made sense to some scientists.

From studies in rabbits and rat heart cells, McCully’s group has reported that the plasma membranes of cells engulf the mitochondria and shuttle them inside, where they fuse with the cell’s internal mitochondria. There, they seem to cause molecular changes that help recover heart function: When comparing blood- and oxygen-deprived pig hearts treated with mitochondria to ones receiving placebos, McCully’s group saw differences in gene activity and proteins that indicated less cell death and less inflammation.

About 10 years ago, Sitaram Emani, a cardiac surgeon at Boston Children’s Hospital, reached out to McCully about his work with animal hearts. Emani had seen how some babies with heart defects couldn’t fully recover after heart surgery complications and wondered whether McCully’s mitochondria transplantation method could help them.

During surgery to repair heart defects, surgeons use a drug to stop the heart so they can operate. But if the heart is deprived of blood and oxygen for too long, mitochondria start to fail and cells start to die, in a condition called ischemia. When blood begins flowing again, instead of returning the heart to its normal state, it can damage and kill more cells, resulting in ischemia-reperfusion injury.

Since McCully’s eight years of studies in rabbits and pigs hadn’t revealed safety concerns with mitochondria transplantation, McCully and Emani thought it would be worth trying the procedure in babies unlikely to regain enough heart function to come off heart-lung support.

Parents of 10 patients agreed to the experimental procedure, which was approved by the institute’s review board. In a pilot that ran from 2015 to 2018, McCully extracted pencil-eraser-sized muscle samples from the incisions made for the heart surgery, used a filtration technique to isolate mitochondria and checked that they were functional. Then the team injected the organelles into the baby’s heart.

Eight of those 10 babies regained enough heart function to come off life support, compared to just four out of 14 similar cases from 2002 to 2018 that were used for historical comparison, the team reported in 2021. The treatment also shortened recovery time, which averaged two days in the mitochondrial transplant group compared with nine days in the historical control group. Two patients did not survive — in one case, the intervention came after the rest of the baby’s organs began failing, and in another, a lung issue developed four months later. The group has now performed this procedure on 17 babies.

The transplant procedure remains experimental and is not yet practical for wider clinical use, but McCully hopes that it can one day be used to treat kidney, lung, liver, and limb injuries from interrupted blood flow.

The results have inspired other clinicians whose patients suffer from similar ischemia-reperfusion injuries. One is ischemic stroke, in which clots prevent blood from reaching the brain. Doctors can dissolve or physically remove the clots, but they lack a way to protect the brain from reperfusion damage. “You see patients that lose their ability to walk or talk,” says Melanie Walker, an endovascular neurosurgeon at the University of Washington School of Medicine in Seattle. “You just want to do better and there’s just nothing out there.”

Walker came across McCully’s mitochondrial transplant studies 12 years ago and, in reading further, was especially struck by a report on mice from researchers at Massachusetts General Hospital and Harvard Medical School that showed the brain’s support and protection cells—the astrocytes—may transfer some of their mitochondria to stroke-damaged neurons to help them recover. Perhaps, she thought, mitochondria transplantation could help in human stroke cases too.

She spent years working with animal researchers to figure out how to safely deliver mitochondria to the brain. She tested the procedure’s safety in a clinical trial with just four people with ischemic stroke, using a catheter fed through an artery in the neck to manually remove the blockage causing the stroke, then pushing the catheter further along and releasing the mitochondria, which would travel up blood vessels to the brain.

The findings, published in 2024 in the Journal of Cerebral Blood Flow & Metabolism, show that the infused patients suffered no harm; the trial was not designed to test effectiveness. Walker’s group is now recruiting participants to further assess the intervention’s safety. The next step will be to determine whether the mitochondria are getting where they need to be, and functioning. “Until we can show that, I do not believe that we will be able to say that there’s a therapeutic benefit,” Walker says.

Researchers hope that organ donation might also gain from mitochondria transplants. Donor organs like kidneys suffer damage when they lack blood supply for too long, and transplant surgeons may reject kidneys with a higher risk of these injuries.

To test whether mitochondrial transplants can reinvigorate them, transplant surgeon-scientist Giuseppe Orlando of Wake Forest University School of Medicine in Winston-Salem and his colleagues injected mitochondria into four pig kidneys and a control substance into three pig kidneys. In 2023 in the Annals of Surgery, they reported fewer dying cells in the mitochondria-treated kidneys and far less damage. Molecular analyses also showed a boost in energy production.

It’s still early days, Orlando says, but he’s confident that mitochondria transplantation could become a valuable tool in rescuing suboptimal organs for donation.

The studies have garnered both excitement and skepticism. “It’s certainly a very interesting area,” says Koning Shen, a postdoctoral mitochondrial biologist at the University of California, Berkeley, and coauthor of an overview of the signaling roles of mitochondria in the 2022 Annual Review of Cell and Developmental Biology. She adds that scaling up extraction of mitochondria and learning how to store and preserve the isolated organelles are major technical hurdles to making such treatments a larger reality. “That would be amazing if people are getting to that stage,” she says.

“I think there are a lot of thoughtful people looking at this carefully, but I think the big question is, what’s the mechanism?” says Navdeep Chandel, a mitochondria researcher at Northwestern University in Chicago. He doubts that donor mitochondria fix or replace dysfunctional native organelles, but says it’s possible that mitochondria donation triggers stress and immune signals that indirectly benefit damaged tissue.

Whatever the mechanism, some animal studies do suggest that the mitochondria must be functional to impart their benefits. Lance Becker, chair of emergency medicine at Northwell Health in New York who studies the role of mitochondria in cardiac arrest, conducted a study comparing fresh mitochondria, mitochondria that had been frozen then thawed, and a placebo to treat rats following cardiac arrest. The 11 rats receiving fresh, functioning mitochondria had better brain function and a higher rate of survival three days later than the 11 rats receiving a placebo; the non-functional frozen-thawed mitochondria did not impart these benefits.

It will take more research into the mechanisms of mitochondrial therapy, improved mitochondria delivery techniques, larger trials and a body of reported successes before mitochondrial transplants can be FDA-approved and broadly used to treat ischemia-reperfusion injuries, researchers say. The ultimate goal would be to create a universal supply of stored mitochondria — a mitochondria bank, of sorts — that can be tapped for transplantation by a wide variety of health care providers.

“We’re so much at the beginning—we don’t know how it works,” says Becker. “But we know it’s doing something that is mighty darn interesting.”

This article originally appeared in Knowable Magazine, a nonprofit publication dedicated to making scientific knowledge accessible to all. Sign up for Knowable Magazine’s newsletter.

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Knowable Magazine explores the real-world significance of scholarly work through a journalistic lens.

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“Things we’ll never know” science fair highlights US’s canceled research

dei, diversity, misinformation, pandemic, research, Science, science funding / /

Congressional Democrats host scientists whose grants have been canceled.

Like a research conference, but focused on research that may never happen now. Credit: John Timmer

Washington, DC—From a distance, the gathering looked like a standard poster session at an academic conference, with researchers standing next to large displays of the work they were doing. Except in this case, it was taking place in the Rayburn House Office Building on Capitol Hill, and the researchers were describing work that they weren’t doing. Called “The things we’ll never know,” the event was meant to highlight the work of researchers whose grants had been canceled by the Trump administration.

A lot of court cases have been dealing with these cancellations as a group, highlighting the lack of scientific—or seemingly rational—input into the decisions to cut funding for entire categories of research. Here, there was a much tighter focus on the individual pieces of research that had become casualties in that larger fight.

Seeing even a small sampling of the individual grants that have been terminated provides a much better perspective on the sort of damage that is being done to the US public by these cuts and the utter mindlessness of the process that’s causing that damage.

“It’s no way to do science,” one of the researchers told us.

Targeting diversity and more

While many of the scientists were perfectly willing to identify themselves at the event, more than one asked us not to name them in any coverage. Another noted that, while she wasn’t concerned about retaliation from the federal government, she was at a state university in a state with a Republican governor and so could still face problems. As a result, we’re not identifying any of the scientists we talked to in this article.

With a few exceptions, most of these scientists could only surmise why their research was cut. A couple of them were funded by programs that were meant to increase minority participation in the sciences and so were targeted as DEI. Another was at Harvard and saw his materials science research into new refrigerants canceled, ostensibly because Harvard hadn’t cracked down hard enough on campus antisemitism (“ostensibly” because the government has also issued a series of demands that have nothing to do with antisemitism).

In their rush to terminate grants, each agency settled on a single form letter that told researchers that their work was being defunded because it no longer reflected agency priorities. A number of said researchers surmised that they lost their support because, at the time the grant was initially funded, many federal agencies required attempts to, as the National Science Foundation termed it, “broaden participation.” This left them at risk of falling afoul of the new administration’s anti-DEI efforts.

A few of them planned to eliminate the language they suspect offended DOGE and send in a new grant request. But, given the lack of details in the termination letters, all of them would have to guess as to the problem. And at least one said that the entire program that had funded her grant had since been eliminated, so this wasn’t even an option.

Many of the grants were focused on STEM education, and it’s extremely difficult to imagine that people will be better off without the work happening. One involved figuring out how to better incorporate instruction in quantum mechanics into high school and college education, rather than limiting this increasingly important topic to a handful of physics specialists. Another was focused on trying to help engineers communicate better with the communities that would ultimately use the things they were designing (she cited Google Glass and the Segway as examples of the problems that result when this doesn’t happen).

A large multi-university collaboration had put together a program to help deaf students navigate careers in science, providing support at the undergraduate, graduate, and post-doctoral levels. The effort received multiple grants from different sources, but a number were part of a diversifying science effort, and all of those have been cut.

For a couple of the researchers present, the damage being done to the educational pipeline was personal: they had received prestigious grants that are intended to ease the transition between post-doctoral training and starting a faculty job. This funding helps them stay in a post-doctoral position long enough to develop a solid research program, then partially funds the process of starting up a lab to pursue that program. But for these researchers, the rug had been pulled out from under them partway through the process—funding that was cut even though (in one case) they were simply studying the regeneration of the retina in an experimental organism.

Pandemics, misinformation, and confusion

The damage is far from limited to education and diversity issues. Despite having been in power during a pandemic that ultimately killed well over a million Americans, the administration has decided that any pandemic-related work is not a priority. So, an entire pandemic preparedness program was scrapped. A pair of researchers was there to talk about the Antiviral Drug Discovery program (AViDD), which had been funded to develop drugs that target various emerging viral threats, such as coronaviruses and the families that include Ebola, Zika, and measles. The idea behind AViDD is to have treatments ready that could limit the spread of any new, threatening version of these viruses in order to give us time to develop vaccines.

AViDD had been funded to the tune of $1.2 billion, included nine dedicated research centers, and involved researchers at 90 institutions. In total, it had spent about half that money in developing 35 treatment candidates that targeted seven different viral families. And then the funding for the entire program was eliminated before any of those candidates could be pursued any further—the researchers likened it to building half a bridge.

Another area that has been targeted is misinformation research. One small team included an academic who’s also a Reddit moderator; they trained an AI model to flag posts that might require moderator intervention, potentially cutting down on the workload of human moderators, who are often volunteers. The project had gotten to the point where they were looking for a company willing to test the system on some user-generated discussions it hosted; now it’s on indefinite hold.

In other instances, it was hard to tell what had triggered the elimination of funding. One team was developing baseline data to allow us to track the presence of antibiotic resistance genes in municipal wastewater, which could be useful for various public health measures. It’s not entirely clear why that funding was canceled—possibly it was considered pandemic-related? The same uncertainty applies to a group of researchers who were trying to develop methods to identify which Arctic infrastructure projects would benefit the most people in Alaska. The researchers involved suspect their efforts to engage native communities probably triggered DOGE’s DEI filters, but they received the same form letter as everyone else.

Even when it was obvious why a given bit of research was cut, it didn’t feel any less stupid. One grant that was targeted funded research on prostate cancer in African Americans, which undoubtedly set off diversity alarms. But the researcher who had received it highlighted that, because of a complicated mix of genetics, environmental exposures, and occupational risks, prostate cancer is diagnosed at a 76 percent higher rate in African Americans, and they die because of it at twice the rate of whites. By stopping this sort of research, we’re committing to perpetuating these disparities, despite the administration’s rhetoric of eliminating racial preferences.

No way to do science

Although the likely loss of a large amount of interesting science is obviously a major problem, in many ways the uncertainty is worse. A number of the people there had seen funding restored due to temporary restraining orders issued in response to a number of lawsuits. But they couldn’t be confident that the money wouldn’t go away again due to a different ruling during the appeals process. And, even if they were to prevail in the courts on the initial cancellation, there were already fears that the government would think of some other justification to try to take the money away a second time.

The uncertainty makes it impossible to plan any significant distance ahead or hire anyone to do the work for longer-term projects. Many researchers are starting to write grants targeting non-federal funding sources, increasing the competition for that money and making it less likely that the effort will have any payoff.

Looming over all of this are the huge research cuts in the recently passed budget, which will cripple many of the agencies involved here starting in the next fiscal year. This raises questions about how much of this money might ever come back, even if the grants were reformulated to get past whatever issue got them cut.

Is there anything to be done? The event was being put on by the Democrats on the House Science Committee, and one of their members tried to offer some hope for the long-term situation. “Many of us on this committee are going to fight to claw back some of these cuts,” said Representative April McClain Delaney of Maryland. But that would require some cooperation with Republicans in the House and Senate, who hold a decisive number of votes and have so far seemed comfortable with the cuts to science funding. And they’d need to find a bill to attach it to that Trump would feel compelled to sign.

But that’s the future. For now, nobody offered much hope for the grants that are currently being targeted—after all, Congress had already given the federal government the money and, in many cases, directed it to spend it on these issues. At this point, the most scientists can hope for is that the US legal system ultimately acknowledges that the decision to cut their funding runs afoul of these congressional directives. And that may take years to be resolved.

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John is Ars Technica’s science editor. He has a Bachelor of Arts in Biochemistry from Columbia University, and a Ph.D. in Molecular and Cell Biology from the University of California, Berkeley. When physically separated from his keyboard, he tends to seek out a bicycle, or a scenic location for communing with his hiking boots.

“Things we’ll never know” science fair highlights US’s canceled research Read More »

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Sizing up the 5 companies selected for Europe’s launcher challenge

Europe, european space agency, isar aerospace, launch, MaiaSpace, orbex, pld space, rocket factory Augsburg, Science, Space / /

The European Space Agency has selected five launch startups to become eligible for up to 169 million euros ($198 million) in funding to develop alternatives to Arianespace, the continent’s incumbent launch service provider.

The five companies ESA selected are Isar Aerospace, MaiaSpace, Rocket Factory Augsburg, PLD Space, and Orbex. Only one of these companies, Isar Aerospace, has attempted to launch a rocket into orbit. Isar’s Spectrum rocket failed moments after liftoff from Norway on a test flight in March.

None of these companies are guaranteed ESA contracts or funding. Over the next several months, the European Space Agency and the five launch companies will negotiate with European governments for funding leading up to ESA’s ministerial council meeting in November, when ESA member states will set the agency’s budget for at least the next two years. Only then will ESA be ready to sign binding agreements.

In a press release, ESA referred to the five companies as “preselected challengers” in a competition for ESA support in the form of launch contracts and an ESA-sponsored demonstration to showcase upgraded launch vehicles to heave heavier payloads into orbit. So far, all five of the challengers are focusing on small rockets.

Earlier this year, ESA released a request for proposals to European industry for bids to compete in the European Launch Challenge. ESA received 12 proposals from European companies and selected five to move on to the next phase of the challenge.

A new way of doing business

In this competition, ESA is eschewing a rule that governs nearly all of the space agency’s other programs. This policy, known as geographic return, guarantees industrial contracts to ESA member states commensurate with the level of money they put into each project. The most obvious example of this is Europe’s Ariane rocket family, whose development was primarily funded by France, followed by Germany in second position. Therefore, the Ariane 6 rocket’s core stage and engines are built in France, and its upper stage is manufactured in Germany.

Sizing up the 5 companies selected for Europe’s launcher challenge Read More »

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Wildfires are challenging air quality monitoring infrastructure

air quality, Science, syndication / /

Can the US’s system to monitor air pollutants keep up with a changing climate?

The Downtown Manhattan skyline stands shrouded in a reddish haze as a result of Canadian wildfires on June 6, 2023. Credit: Lokman Vural Elibol/Anadolu Agency via Getty Images

Ten years ago, Tracey Holloway, an atmospheric scientist at the University of Wisconsin–Madison, would have said that air pollution in the United States was a huge success story. “Our air had been getting cleaner and cleaner almost everywhere, for almost every pollutant,” she said. But in June 2023, as wildfire smoke from Canada spread, the air quality dropped to historically low levels in her home state of Wisconsin.

Just last month, the region’s air quality dipped once more to unhealthy levels. Again, wildfires were to blame.

While the US has made significant strides in curbing car and industrial pollution through setting emission limits on industrial facilities and automakers, the increasing frequency and intensity of fires are “erasing the gains that we have obtained through this pollutant control effort,” said Nga Lee “Sally” Ng, an aerosol researcher at Georgia Institute of Technology.

The changing dynamics present a challenge for both residents and researchers tracking air quality. Many of the high-quality monitors used to measure pollution reside near large cities and stationary sources, such as coal-powered plants, and don’t cover the US uniformly. Regions that lack such stations are called air quality monitoring deserts, and they may leave vulnerable populations in the dark about their local conditions.

The current infrastructure also isn’t set up to fully account for the shifting behavior of wildfire smoke, which can travel hundreds of miles or more from fire sources to affect air quality and public health in distant communities. That smoke can also include toxins, such as lead when cars and homes burn.

“Fires are really changing the story,” said Holloway.

Since the introduction of the Air Pollution Control Act of 1955, air quality has been recognized as a national issue in the United States. Then with the enactment of the Clean Air Act in 1970 and following amendments, researchers and federal agencies began to monitor the level of pollutants, particularly carbon monoxide, nitrogen dioxide, ozone, particulate matter, and sulfur dioxide, to identify if these were up to the established National Ambient Air Quality Standards.

The Environmental Protection Agency uses these pollutant levels to calculate an air quality index, or AQI, a numerical and color-coded system scaled from 0 to 500 that informs the public how safe the air is. Higher numbers, associated with red, purple, and maroon, indicate worse quality; in June 2023, for example, parts of Wisconsin topped 300, indicating “hazardous” air. All residents were advised to stay indoors as much as possible.

The EPA and other federal agencies make use of various networks of advanced ground monitors that can pick up on different air pollutants, and many experts say that the US has one of the most advanced air quality tracking systems in the world.

Still, there are gaps: Regulatory monitors cost around $50,000 upfront and require continuous maintenance, so states place them in locations where researchers expect pollution may be high. Currently, there are 4,821 active monitors across the US in the EPA’s AirData system—many of which were installed in the 1990s and 2000s—but they are more likely to be near more populated areas and in states in the West and Northeast, creating air quality monitoring deserts elsewhere, according to a new study published in April.

When looking at their distribution, researchers at The Pennsylvania State University found that 59 percent of US counties—home to more than 50 million people—lacked an air quality monitoring site. Many of those air quality monitoring deserts were in rural areas in the South and Midwest. Counties with higher poverty rates and a higher concentration of Black and Hispanic residents were also more likely to be air quality monitoring deserts when accounting for population.

Similarly, a Reuters investigation found that 120 million Americans live in counties that have no monitors for small particle pollution and that in 2020, “the government network of 3,900 monitoring devices nationwide has routinely missed major toxic releases and day-to-day pollution dangers,” including those linked to refinery explosions. (In response to a request for comment, an EPA spokesperson noted that the agency “continues to work closely with state, local, and tribal monitoring programs to expand the use of air sensors to improve measurement coverage, which provide near-real time data to a number of publicly available sources, such as the AIRNow Fire and Smoke Map.”)

These gaps in coverage can be accentuated with wildfires, which often originate in sparsely populated areas without monitor coverage. Wildfires can also be unpredictable, making it difficult to identify priority sites for new monitors. “You certainly can’t anticipate what areas are going to see wildfire smoke,” said Mary Uhl, executive director of Western States Air Resources Council, which shares air quality information across 15 western state air agencies. Meanwhile, wildfire pollutants can spread widely from their original source, and smoke particles can sometimes travel for up to 10 days, Ng pointed out.

Such shifting dynamics are driving researchers to expand their monitoring infrastructure and complement it with crowdsourced and satellite data to capture the widespread pollution. “There will be potential to increase the spatial covering of these monitoring networks,” said Ng. “Because, as you can see, we could still make use of better measurement, maybe at the different community level, to better understand the air that we are being exposed to.”

To expand coverage in a cost-efficient way, agencies are investigating a variety of different approaches and technologies. Low-cost monitors now allow people to crowdsource data about air quality in their communities. (However, these tend to be less precise and accurate than the high-grade instruments.) State, local, and tribal agencies also play a critical role in monitoring air quality, such as New York’s Community Air Monitoring Initiative, which tracked pollution for a year using mobile monitoring in 10 disadvantaged communities with high air pollution burdens. And the EPA has a pilot program that loans compact mobile air monitoring systems to air quality professionals, who can set them up in their vehicles to map air quality during and after wildfires.

Satellites can also provide critical information since they can estimate levels of gases and pollutants, providing data about where pollution levels are highest and how pollutants are transported. “We can see where we’re missing things in those deserts,” said Uhl.

This strategy might be helpful to address the challenge with wildfires because satellites can get a more global view of the spread of pollutants. Fires “change season to season, so they’re not always coming from the same place,” said Holloway, who leads a team that uses NASA satellite data to monitor air quality. “And I think really what you need is a way of evaluating what’s going on over a wide area. And these satellites up in space, I think, offer exactly the tool for the job.”

Other advancements allow scientists to study the composition of pollution more granularly, since different pollutants can have different toxicities and health effects. For example, particulate matter 2.5, or PM2.5—which has a diameter of 2.5 micrometers or less—can cause respiratory and heart problems. Ng led the establishment of a system called ASCENT, or the Atmospheric Science and Chemistry Measurement Network, which measures the specific chemical constituents in PM2.5 to identify which particles might be the most toxic to human health, along with aiming to answer many other scientific questions.

After the Eaton Canyon and Palisades fires that burned across Los Angeles County in January 2025, Ng and colleagues used the system and identified that lead concentration increased approximately 110 times over the average levels, likely due to the ignition of the lead-ridden vehicles, plastics, buildings, and other fuel. The system works as a “magnifying glass to look into PM2.5,” said Ng. Currently, they have 12 sites and hope to expand ASCENT to more locations in the future if resources are available.

Different approaches to collecting air quality monitoring data, along with computational modeling, could be combined to improve researchers’ understanding of air pollution and expand air quality information to underserved populations, said Holloway.

Today, although wildfires represent a new challenge, “we have all these additional tools to help us understand air quality,” said Uhl. “And in the end, that’s what we want to do: We want to understand it. We want to be able to have some ideas, some ways to predict it, to ultimately protect public health.”

This article was originally published on Undark. Read the original article.

Wildfires are challenging air quality monitoring infrastructure Read More »

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Watch this cucumber squirt out its seeds at ballistic speeds

ballistics, Biomechanics, botany, rapid plant movement, Science, seed dispersion, squirting cucumbers / /

Take a look at squirting cucumber explosive seed dispersal in real time and slowed down. Credit: Helen Gorges/CC BY-NC-ND

One doesn’t normally associate ballistics with botany, but most of us don’t study “squirting” cucumbers—so called because they disperse their seeds by explosively propelling them out into the world. Scientists took a series of high-speed videos, both in the wild and in the lab, to learn more about the underlying biomechanics of this plant’s method of seed dispersal. Graduate student Helen Gorges of Kiel University’s Zoological Institute in Germany presented the findings at the Society for Experimental Biology Annual Conference in Antwerp, Belgium.

Also known as the “noli me tangere,” aka “touch me not,” the squirting cucumber (Ecballium elaterium) is often considered a weed or invasive species, although in some regions it’s viewed as ornamental. Fun fact: The fruit extract is a powerful laxative. If swallowed or inhaled through the nose, it can be poisonous, causing edemas and necrosis of the nasal mucosa, among other complications. That same fruit, once ripened, can squirt out a stream of mucus-like liquid containing seed pods at high speeds—an example of rapid plant movement.

As glucosides in the sap of the fruit’s tissue cells build up, so does the internal pressure, eventually causing the fruit to detach from the stalk. At that point, the pericarp contracts, and both the fruit and the seeds are violently expelled through the resulting hole. The squirting action is further aided by structural changes in the fruit as it dehydrates and its cells coil, bend, or twist in response (hygroscopic movement).

Squirting cucumber explosive seed dispersal (over 300x slowed down). Credit: Helen Gorges/CC BY-NC-ND

It’s actually not the most effective means of seed dispersal, per a 2019 study. That’s good news for almond orchards, for example, since farmers can target their weed-killing efforts to the most likely affected areas. And the plant tissue tends to fracture from the force of the ballistic seed dispersal. “Many factors have to interact perfectly to disperse the seeds in the most efficient way, while not destroying the whole plant too early,” said Gorges, who wanted to learn more about the biomechanics that control the fruit as it ripens and prepares for seed dispersion.

Watch this cucumber squirt out its seeds at ballistic speeds Read More »

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As California faces court battles, states scramble to save their climate goals

climate goals, electrification, EVs, Policy, Science, syndication / /

With or without authority to regulate heightened emissions, states plan to meet climate goals.

Traffic jam forms on Interstate 5 north of Los Angeles. Credit: Hans Gutknecht/MediaNews Group/Los Angeles Daily News

This article originally appeared on Inside Climate News, a nonprofit, non-partisan news organization that covers climate, energy, and the environment. Sign up for their newsletter here.

When President Donald Trump signed legislation to revoke California’s authority to enforce stricter tailpipe emissions standards and to ban sales of gas-powered cars by 2035, the effects rippled far beyond the Golden State.

Seventeen states relied on California’s Clean Air Act waivers to adopt stronger vehicle pollution rules on their own, including New York, New Jersey, Oregon, Massachusetts, and Washington.

California, joined by several states, immediately sought a court injunction, calling the revocation illegal on the basis that the waivers are not subject to congressional review and that it violated decades of legal precedent and procedure. These same states recently launched an Affordable Clean Cars Coalition to coordinate legal action and policy to defend their rights to transition to cleaner vehicles.

As the legal battle plays out, states that have relied on the waivers are leaning into expanding multimillion-dollar ways to keep their EV transitions on track. Among their efforts: amping up rebates, tightening rules on the carbon intensity of fuels, and cracking down on pollution where trucks congregate.

“Climate change is still around, whether we have the waiver or not. So we have to figure out ways to make sure that we’re doing what we can to address the problem at hand,” said Michelle Miano, who heads the New Mexico environment protection division of the Environment Department.

According to data from the California Air Resources Board, the states that have passed tougher pollution rules account for about 40 percent of new light-duty vehicle registrations and 25 percent of new heavy-duty vehicle registrations in the United States, where the transportation sector is the highest source of greenhouse gas emissions as of 2022.

Among these stronger rules are the Advanced Clean Cars (ACC) I and II and Advanced Clean Trucks (ACT), which require automakers to sell a growing share of electric passenger cars and medium and heavy-duty trucks to reduce emissions from gasoline-powered counterparts.

The goal is for all new vehicles sold to be electric by 2035.

Bolstering incentives 

Without ACC and ACT, states are betting they can increase demand for EVs by reducing the costs of buying a vehicle with rebates, vouchers, and grants and boosting the number of charging stations in their states. These incentives can range from a few thousand dollars for individual EV purchases to hundreds of thousands for building charging infrastructure and fleet upgrades.

On June 18, New York announced a $53 million expansion to its voucher program for electrifying last-mile truck fleets, offering vouchers from $340,000 to $425,000 for each truck, depending on the model.

“Despite the current federal administration’s efforts to erode certainty in the ongoing transition to cleaner vehicles, New York State will continue to act to protect our air, lands, and waters,” said Amanda Lefton, commissioner of the Department of Environmental Conservation.

In Oregon, where over a third of in-state emissions are from transportation use, the government this month opened applications for $34 million in grants toward the purchase of zero-emission trucks and developing charging stations for EVs or retrofitting diesel trucks. Lawmakers are considering expanding a popular rebate program through a bill introduced in February. The program so far has given car owners almost $100 million for EV purchases. (The program has been suspended twice after running out of money. It resumed as of May 2025.)

In Massachusetts, Gov. Maura Healey promised in May to announce “dedicated additional grant funding” for electric vehicles and vowed to increase “grant funding opportunities” for charging. Advocacy groups, including the Environmental League of Massachusetts, are counting on increased funding for its MOR-EV rebate program, which provides up to $3,500 for new EV purchases. This year, the rebate program has distributed $15.7 million in total incentives, according to the program’s statistics page.

In Washington state, lawmakers earmarked $126 million—a $16 million increase from 2024—to subsidize purchases of electric truck fleets and chargers. Many states are targeting trucks because they account for a huge share in emissions relative to their number on the road.

Will Toor, executive director of the Colorado Energy Office, credited state rebates and investments in charging infrastructure for helping Colorado reach a 20 percent electric vehicle market share in the first quarter of 2025. One in five new cars sold in the state was electric. Toor also credited the state agency’s EV buyer’s education campaign launched in late 2022, which promoted available rebates and incentives for prospective EV owners.

The scope and generosity of these programs vary widely depending on each state’s climate priorities, budget capacity, and access to federal or market-based funding streams.

“Those types of incentives can be expensive,” said Terrence Gray, director of the Rhode Island Department of Environmental Management. “In Rhode Island, our budget is tight. There’s not a lot of funding available right now, so we would have to make a very strong argument that there’s a strong cost benefit to invest in these types of areas.”

With the Trump administration threatening to cut down federal funding for EV rebates through the Biden-era Inflation Reduction Act, states will have to increasingly rely on themselves to fund these programs.

“The federal government isn’t going to come save us,” said Alex Ambrose, an analyst with the nonpartisan think tank New Jersey Policy Perspective.

Some are already ahead on this. California and Washington state have devised carbon markets that charge major polluters—like oil refiners, power plants, large industrial facilities, and fuel suppliers—for each ton of carbon dioxide they release. California’s auctions bring in about $3 to $4 billion per year, which support programs such as public transit and EV rebates. Washington’s system, launched in 2023, covers around 97 major emitters and has raised over $3 billion in its first two years, funding clean transportation, air quality devices, and EV chargers.

The states of New York, New Jersey, Massachusetts, and other Northeast and Mid-Atlantic states have signed up to the Regional Greenhouse Gas Initiative, or RGGI, which is a cooperative cap-and-invest program launched in 2009 that limits emissions from the power sector and reinvests proceeds into clean energy programs like EV rebates.

Making fuels greener

While many states focus on promoting electric vehicles, others are also targeting the fuel of gas-powered cars, by adopting or developing standards that lower the carbon intensity.

These policies require fuel producers and importers to blend cleaner alternatives like biofuels, renewable diesel, or electricity into the fuel mix.

Patterned after California, Washington has a clean fuel standard in effect since 2023, targeting a 20 percent reduction in carbon intensity of transportation fuels by 2034 compared to 2017 levels.

Oregon has a similar program in place that aims to reduce carbon intensity in fuels by 37 percent by 2035.

New Mexico approved its Clean Transportation Fuel Standard in March 2024. A formal adoption hearing before the Environmental Improvement Board is scheduled to begin in September.

“We know that those (electric) vehicles aren’t for everyone and so we are very respectful of folks that decide to not purchase them,” said Miano, New Mexico’s environment protection division head.

No East Coast states have enacted a clean fuel standard, but New York state legislators may change that.

There are bills in the State Senate and Assembly that, if passed, would require fuel providers to reduce the carbon intensity of their transportation fuels by at least 20 percent by 2030. (Legislation has passed the Senate but remains at the committee level in the Assembly as of June.)

Michigan also had bills introduced in its Senate and House in 2023, but neither passed before the 2024 session ended. Similar bills have not been introduced since then.

Some of these clean fuel standards have faced criticism from environmental advocates, who argue that they allow polluters to buy their way out of reducing emissions.

But Trisha DelloIacono, policy head at advocacy group CALSTART, said the fuel standards remain one of the few politically viable tools to gradually shift the transportation sector toward cleaner fuels.

“What we need to be looking at right now is incremental changes and incremental progress in a place where we’re fighting tooth and nail to hold on to what we have,” DelloIacono said.

Where trucks congregate

There’s also a policy tool called indirect source rules, or ISR.

The rules are called “indirect” because they don’t regulate the vehicles themselves, but the facilities that attract emissions-heavy traffic, like large warehouses, ports, or rail yards. The rules hold the facilities owners or operators responsible for reducing or offsetting the pollution from their profitable traffic.

Studies show that the pollution from these trucks often ends up in nearby neighborhoods, which are disproportionately lower-income and communities of color.

California is currently the only state enforcing ISRs.

In Southern California, large warehouses must take steps to reduce the pollution caused by truck visits, either by switching to electric vehicles, installing chargers, or paying into a clean air fund. It’s the first rule of its kind in the country and it survived a court challenge in 2023, paving the way for other states to consider similar action.

New York is one of them. Its lawmakers introduced a bill in January that could require warehouses with over 50,000 square feet to reduce emissions from trucks by meeting certain benchmarks, such as hosting electric deliveries or offering bike loading zones. New York City has its own version of the rule under deliberation in the Council. As of June 2025, the bill remains stalled in the environmental committee. City Council has until December to act before the bill expires.

In New Jersey, where warehouse growth has boomed, legislators in 2024 proposed a bill that would require “high-traffic facilities” to apply for air pollution permits and provide plans to reduce diesel truck pollution.

“This is really being pushed by the community groups and environmental justice communities, especially in North Jersey. But also, warehouses are starting to pop up even in very rural parts of South Jersey. So this is very quickly becoming a statewide issue in New Jersey,” said Ambrose of the New Jersey Policy Perspective.

In Colorado, its regional air quality council in April announced plans to ask its air quality control commission to use ISR for areas with the worst air quality.

Industry groups, especially in the logistics sector, are pushing back. The industry group Supply Chain Federation told The Wall Street Journal that the southern California ISR was a “backdoor approach [that] does little to cut emissions and instead raises costs, disrupts supply chains.”

Still, experts say this may be one of the few options left for states to cut emissions from traffic-heavy facilities. Because these rules don’t directly regulate the car companies or trucks themselves, they don’t need federal approval.

“We definitely have to be nimble and fluid and also understand the kind of landscape in the state,” DelloIacono said.

Photo of Inside Climate News

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Ancient skull may have been half human, half Neanderthal child

anthropology, Archaeology, Science / /

The mandible had been separated from the skeleton, and both it and the neurocranium are incomplete, so they were reconstructed and consolidated with plaster. CT scanning made it possible to check that older reconstructive work to ensure it had not masked any elements that may have influenced the taxonomic classification, per the authors. The team also scanned the skulls of three Homo neanderthalensis skulls in the collection of the Musee de l’Homme in Paris and compared those skull characteristics with the Skuhl Cave skull and mandible.

They concluded that the neurocranium’s parietal and temporal bones, and the shape of the bony labyrinth, were consistent with Homo sapiens. However, other features, like the receded and high location of the posterior rim of the foramen magnum, indicated a possible Neanderthal lineage. And the mandible showed distinct Neanderthal characteristics, leading to the determination that the child was a hybrid of the two species.

Co-author Anne Dambricourt Malassé of the Institute of Human Paleontology in Paris admitted that she once thought such a hybridization would not have been viable; the results of their analysis demonstrate that it is possible, although the child in question died very young. These findings may also prompt a revisiting of the longstanding assumption that Skuhl Cave was a Homo sapiens gravesite.

“This study is maybe the first that has put the Skhul child’s remains on a scientific basis,” John Hawks of the University of Wisconsin-Madison, who wasn’t involved with the study, told New Scientist. “The old reconstruction and associated work, literally set in plaster, did not really enable anyone to compare this child with a broader array of recent children to understand its biology.” That said, he cautioned that without extracting and analyzing a DNA sample, one can’t make a definitive determination: “Human populations are variable and there can be a lot of variability in their appearance and physical form even without mixing with ancient groups like Neanderthals.”

L’Anthropologie, 2025. DOI: 10.1016/j.anthro.2025.103385  (About DOIs).

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Figuring out why a nap might help people see things in new ways

Biology, Insight, memory, naps, neurobiology, Science, sleep / /

An EEG signal of sleep is associated with better performance on a mental task.

The guy in the back may be doing a more useful activity. Credit: XAVIER GALIANA

Dmitri Mendeleev famously saw the complete arrangement of the periodic table after falling asleep on his desk. He claimed in his dream he saw a table where all the elements fell into place, and he wrote it all down when he woke up. By having a eureka moment right after a nap, he joined a club full of rather talented people: Mary Shelley, Thomas Edison, and Salvador Dali.

To figure out if there’s a grain of truth to all these anecdotes, a team of German scientists at the Hamburg University, led by cognitive science researcher Anika T. Löwe, conducted an experiment designed to trigger such nap-following strokes of genius—and catch them in the act with EEG brain monitoring gear. And they kind of succeeded.

Catching Edison’s cup

“Thomas Edison had this technique where he held a cup or something like that when he was napping in his chair,” says Nicolas Schuck, a professor of cognitive science at the Hamburg University and senior author of the study. “When he fell asleep too deeply, the cup falling from his hand would wake him up—he was convinced that was the way to trigger these eureka moments.” While dozing off in a chair with a book or a cup doesn’t seem particularly radical, a number of cognitive scientists got serious about re-creating Edison’s approach to insights and testing it in their experiments.

One of the recent such studies was done at Sorbonne University by Célia Lacaux, a cognitive neuroscientist, and her colleagues. Over 100 participants were presented with a mathematical problem and told it could be solved by applying two simple rules in a stepwise manner. However, there was also an undescribed shortcut that made reaching the solution much quicker. The goal was to see if participants would figure this shortcut out after an Edison-style nap. The scientists would check whether the eureka moment would show in EEG.

Lacaux’s team also experimented with different objects the participants should hold while napping: spoons, steel spheres, stress balls, etc. It turned out Edison was right, and a cup was by far the best choice. It also turned out that most participants recognized there was a hidden rule after the falling cup woke them up. The nap was brief, only long enough to enter the light, non-REM N1 phase of sleep.

Initially, Schuck’s team wanted to replicate the results of Lacaux’s study. They even bought the exact same make of cups, but the cups failed this time. “For us, it just didn’t work. People who fell asleep often didn’t drop these cups—I don’t know why,” Schuck says.

The bigger surprise, however, was that the N1 phase sleep didn’t work either.

Tracking the dots

Schuck’s team set up an experiment that involved asking 90 participants to track dots on a screen in a series of trials, with a 20-minute-long nap in between. The dots were rather small, colored either purple or orange, placed in a circle, and they moved in one of two directions. The task for the participants was to determine the direction the dots were moving. That could range from easy to really hard, depending on the amount of jitter the team introduced.

The insight the participants could discover was hidden in the color coding. After a few trials where the dots’ direction was random, the team introduced a change that tied the movement to the color: orange dots always moved in one direction, and the purple dots moved in the other. It was up to the participants to figure this out, either while awake or through a nap-induced insight.

Those dots were the first difference between Schuck’s experiment and the Sorbonne study. Lacaux had her participants cracking a mathematical problem that relied on analytical skills. Schuck’s task was more about perceptiveness and out-of-the-box thinking.

The second difference was that the cups failed to drop and wake participants up. Muscles usually relax more when sleep gets deeper, which is why most people drop whatever they’re holding either at the end of the N1 phase or at the onset of the N2 phase, when the body starts to lose voluntary motor control. “We didn’t really prevent people from reaching the N2 phase, and it turned out the participants who reached the N2 phase had eureka moments most often,” Schuck explains.

Over 80 percent of people who reached the deeper, N2 phase of sleep found the color-coding solution. Participants who fell into a light N1 sleep had a 61 percent success rate; that dropped to just 55 percent in a group that stayed awake during their 20-minute nap time. In a control group that did the same task without a nap break, only 49 percent of participants figured out the hidden trick.

The divergent results in Lacaux’s and Schuck’s experiments were puzzling, so the team looked at the EEG readouts, searching for features in the data that could predict eureka moments better than sleep phases alone. And they found something.

The slope of genius

The EEG signal in the human brain consists of low and high frequencies that can be plotted on a spectral slope. When we are awake, there are a lot of high-frequency signals, and this slope looks rather flat. During sleep, these high frequencies get muted, there are more low-frequency signals, and the slope gets steeper. Usually, the deeper we sleep, the steeper our EEG slope is.

The team noticed that eureka moments seemed to be highly correlated with a steep EEG spectral slope—the steeper the slope, the more likely people were to get a breakthrough. In fact, the models based on the EEG signal alone predicted eureka moments better than predictions made based on sleep phases and even based on the sleep phases and EEG readouts combined.

“Traditionally, people divided sleep EEG readouts down into discrete stages like N1 or N2, but as usual in biology, things in reality are not as discrete,” Schuck says. “They’re much more continuous, there’s kind of a gray zone.” He told Ars that looking specifically at the EEG trace may help us better understand what exactly happens in the brain when a sudden moments of insight arrives.

But Shuck wants to get even more data in the future. “We’re currently running a study that’s been years in the making: We want to use both EEG and [functional magnetic resonance imaging] at the same time to see what happens in the brain when people are sleeping,” Schuck says. The addition of the fMRI imaging will enable Schuck and his colleagues to see which areas of the brain get activated during sleep. What the team wants to learn from combining EEG and fMRI imagery is how sleep boosts memory consolidation.

“We also hope to get some insights, no pun intended, into the processes that play a role in generating insights,” Schuck adds.

PLOS Biology, 2025.  DOI: 10.1371/journal.pbio.3003185

Photo of Jacek Krywko

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

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Judge: You can’t ban DEI grants without bothering to define DEI

dei, lawsuit, NIH, Policy, Science, science funding, Trump / /

Separately, Trump v. Casa blocked the use of a national injunction against illegal activity. So, while the government’s actions have been determined to be illegal, Young can only protect the people who were parties to this suit. Anyone who lost a grant but wasn’t a member of any of the parties involved, or based in any of the states that sued, remains on their own.

Those issues aside, the ruling largely focuses on whether the termination of grants violates the Administrative Procedures Act, which governs how the executive branch handles decision- and rule-making. Specifically, it requires that any decisions of this sort cannot be “arbitrary and capricious.” And, Young concludes that the government hasn’t cleared that bar.

Arbitrary and capricious

The grant cancellations, Young concludes, “Arise from the NIH’s newly minted war against undefined concepts of diversity, equity, and inclusion and gender identity, that has expanded to include vaccine hesitancy, COVID, influencing public opinion and climate change.” The “undefined” aspect plays a key part in his reasoning. Referring to DEI, he writes, “No one has ever defined it to this Court—and this Court has asked multiple times.” It’s not defined in Trump’s executive order that launched the “newly minted war,” and Young found that administrators within the NIH issued multiple documents that attempted to define it, not all of which were consistent with each other, and in some cases seemed to use circular reasoning.

He also noted that the officials who sent these memos had a tendency to resign shortly afterward, writing, “it is not lost on the Court that oftentimes people vote with their feet.”

As a result, the NIH staff had no solid guidance for determining whether a given grant violated the new anti-DEI policy, or how that might be weighed against the scientific merit of the grant. So, how were they to identify which grants needed to be terminated? The evidence revealed at trial indicates that they didn’t need to make those decisions; DOGE made them for the NIH. In one case, an NIH official approved a list of grants to terminate received from DOGE only two minutes after it showed up in his inbox.

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New evidence that some supernovae may be a “double detonation”

astronomy, astrophysics, Science, supernova, Type Ia supernova, white dwarf / /

Type Ia supernovae are critical tools in astronomy, since they all appear to explode with the same intensity, allowing us to use their brightness as a measure of distance. The distance measures they’ve given us have been critical to tracking the expansion of the Universe, which led to the recognition that there’s some sort of dark energy hastening the Universe’s expansion. Yet there are ongoing arguments over exactly how these events are triggered.

There’s widespread agreement that type Ia supernovae are the explosions of white dwarf stars. Normally, these stars are composed primarily of moderately heavy elements like carbon and oxygen, and lack the mass to trigger additional fusion. But if some additional material is added, the white dwarf can reach a critical mass and reignite a runaway fusion reaction, blowing the star apart. But the source of the additional mass has been somewhat controversial.

But there’s an additional hypothesis that doesn’t require as much mass: a relatively small explosion on a white dwarf’s surface can compress the interior enough to restart fusion in stars that haven’t yet reached a critical mass. Now, observations of the remains of a supernova provide some evidence of the existence of these so-called “double detonation” supernovae.

Deconstructing white dwarfs

White dwarfs are the remains of stars with a similar mass to our Sun. After having gone through periods during which hydrogen and helium were fused, these tend to end up as carbon and oxygen-rich embers: hot due to their history, but incapable of reaching the densities needed to fuse these elements. Left on their own, these stellar remnants will gradually cool.

But many stars are not left on their own; they exist in binary systems with a companion, or even larger systems. These companions can provide the material needed to boost white dwarfs to the masses that can restart fusion. There are two potential pathways for this to happen. Many stars go through periods where they are so large that their gravitational pull is barely enough to hold on to their outer layers. If the white dwarf orbits closely enough, it can pull in material from the other star, boosting its mass until it passes a critical threshold, at which point fusion can restart.

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