Science

us-military’s-x-37b-spaceplane-stays-relevant-with-launch-of-another-mission

US military’s X-37B spaceplane stays relevant with launch of another mission

“Quantum inertial sensors are not only scientifically intriguing, but they also have direct defense applications,” said Lt. Col. Nicholas Estep, an Air Force engineer who manages the DIU’s emerging technology portfolio. “If we can field devices that provide a leap in sensitivity and precision for observing platform motion over what is available today, then there’s an opportunity for strategic gains across the DoD.”

Teaching an old dog new tricks

The Pentagon’s twin X-37Bs have logged more than 4,200 days in orbit, equivalent to about 11-and-a-half years. The spaceplanes have flown in secrecy for nearly all of that time.

The most recent flight, Mission 7, ended in March with a runway landing at Vandenberg after a mission of more than 14 months that carried the spaceplane higher than ever before, all the way to an altitude approaching 25,000 miles (40,000 kilometers). The high-altitude elliptical orbit required a boost on a Falcon Heavy rocket.

In the final phase of the mission, ground controllers commanded the X-37B to gently dip into the atmosphere to demonstrate the spacecraft could use “aerobraking” maneuvers to bring its orbit closer to Earth in preparation for reentry.

An X-37B spaceplane is ready for encapsulation inside the Falcon 9 rocket’s payload fairing. Credit: US Space Force

Now, on Mission 8, the spaceplane heads back to low-Earth orbit hosting quantum navigation and laser communications experiments. Few people, if any, envisioned these kinds of missions flying on the X-37B when it first soared to space 15 years ago. At that time, quantum sensing was confined to the lab, and the first laser communication demonstrations in space were barely underway. SpaceX hadn’t revealed its plans for the Falcon Heavy rocket, which the X-37B needed to get to its higher orbit on the last mission.

The laser communications experiments on this flight will involve optical inter-satellite links with “proliferated commercial satellite networks in low-Earth orbit,” the Space Force said. This is likely a reference to SpaceX’s Starlink or Starshield broadband satellites. Laser links enable faster transmission of data, while offering more security against eavesdropping or intercepts.

Gen. Chance Saltzman, the Space Force’s chief of space operations, said in a statement that the laser communications experiment “will mark an important step in the US Space Force’s ability to leverage proliferated space networks as part of a diversified and redundant space architectures. In so doing, it will strengthen the resilience, reliability, adaptability and data transport speeds of our satellite communications architecture.”

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For some people, music doesn’t connect with any of the brain’s reward circuits

“I was talking with my colleagues at a conference 10 years ago and I just casually said that everyone loves music,” recalls Josep Marco Pallarés, a neuroscientist at the University of Barcelona. But it was a statement he started to question almost immediately, given there were clinical cases in psychiatry where patients reported deriving absolutely no pleasure from listening to any kind of tunes.

So, Pallarés and his team spent the past 10 years researching the neural mechanisms behind a condition they called specific musical anhedonia: the inability to enjoy music.

The wiring behind joy

When we like something, it is usually a joint effect of circuits in our brain responsible for perception—be it perception of taste, touch, or sound—and reward circuits that give us a shot of dopamine in response to nice things we experience. For a long time, scientists attributed a lack of pleasure from things most people find enjoyable to malfunctions in one or more of those circuits.

You can’t enjoy music when the parts of the brain that process auditory stimuli don’t work properly, since you can’t hear it in the way that you would if the system were intact. You also can’t enjoy music when the reward circuit refuses to release that dopamine, even if you can hear it loud and clear. Pallarés, though, thought this traditional idea lacked a bit of explanatory power.

“When your reward circuit doesn’t work, you don’t experience enjoyment from anything, not just music,” Pallarés says. “But some people have no hearing impairments and can enjoy everything else—winning money, for example. The only thing they can’t enjoy is music.”

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Scientists are building cyborg jellyfish to explore ocean depths

Understanding the wakes and vortices that jellyfish produce as they swim is crucial, according to Wu, et al. Particle image velocimetry (PIV) is a vital tool for studying flow phenomena and biomechanical propulsion. PIV essentially tracks tiny tracer particles suspended in water by illuminating them with laser light. The technique usually relies on hollow glass spheres, polystyrene beads, aluminum flakes, or synthetic granules with special optical coatings to enhance the reflection of light.

These particles are readily available and have the right size and density for flow measurements, but they are very expensive, costing as much as $200 per pound in some cases. And they have associated health and environmental risks: glass microspheres can cause skin or eye irritation, for example, while it’s not a good idea to inhale polystyrene beads or aluminum flakes. They are also not digestible by animals and can cause internal damage. Several biodegradable options have been proposed, such as yeast cells, milk, micro algae, and potato starch, which are readily available and cheap, costing as little as $2 per pound.

Wu thought starch particles were the most promising as biodegradable tracers, and decided to study several different kinds of starches to identify the best candidate: specifically, corn starch, arrowroot starch, baking powder, jojoba beads, and walnut shell powder. Each type of particle was suspended in water tanks with moon jellyfish, tracking their movement with a PIV system. They evaluated their performance based on the particles’ size, density, and laser-scattering properties.

Of the various candidates, corn starch and arrowroot starch proved best suited for PIV applications, thanks to their density and uniform size distribution, while arrowroot starch performed best when it came to laser scattering tests. But corn starch would be well-suited for applications that require larger tracer particles since it produced larger laser scattering dots in the experiments. Both candidates matched the performance of commonly used synthetic PIV tracer particles in terms of accurately visualizing flow structures resulting from the swimming jellyfish.

DOI: Physical Review Fluids, 2025. 10.1103/bg66-976x  (About DOIs).

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Deeply divided Supreme Court lets NIH grant terminations continue

The dissents

The primary dissent was written by Chief Justice Roberts, and joined in part by the three Democratic appointees, Jackson, Kagan, and Sotomayor. It is a grand total of one paragraph and can be distilled down to a single sentence: “If the District Court had jurisdiction to vacate the directives, it also had jurisdiction to vacate the ‘Resulting Grant Terminations.’”

Jackson, however, chose to write a separate and far more detailed argument against the decision, mostly focusing on the fact that it’s not simply a matter of abstract law; it has real-world consequences.

She notes that existing law prevents plaintiffs from suing in the Court of Federal Claims while the facts are under dispute in other courts (something acknowledged by Barrett). That would mean that, as here, any plaintiffs would have to have the policy declared illegal first in the District Court, and only after that was fully resolved could they turn to the Federal Claims Court to try to restore their grants. That’s a process that could take years. In the meantime, the scientists would be out of funding, with dire consequences.

Yearslong studies will lose validity. Animal subjects will be euthanized. Life-saving medication trials will be abandoned. Countless researchers will lose their jobs. And community health clinics will close.

Jackson also had little interest in hearing that the government would be harmed by paying out the grants in the meantime. “For the Government, the incremental expenditure of money is at stake,” she wrote. “For the plaintiffs and the public, scientific progress itself hangs in the balance along with the lives that progress saves.”

With this decision, of course, it no longer hangs in the balance. There’s a possibility that the District Court’s ruling that the government’s policy was arbitrary and capricious will ultimately prevail; it’s not clear, because Barrett says she hasn’t even seen the government make arguments there, and Roberts only wrote regarding the venue issues. In the meantime, even with the policy stayed, it’s unlikely that anyone will focus grant proposals on the disfavored subjects, given that the policy might be reinstated at any moment.

And even if that ruling is upheld, it will likely take years to get there, and only then could a separate case be started to restore the funding. Any labs that had been using those grants will have long since moved on, and the people working on those projects scattered.

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Neolithic people took gruesome trophies from invading tribes

A local Neolithic community in northeastern France may have clashed with foreign invaders, cutting off limbs as war trophies and otherwise brutalizing their prisoners of war, according to a new paper published in the journal Science Advances. The findings challenge conventional interpretations of prehistoric violence as bring indiscriminate or committed for pragmatic reasons.

Neolithic Europe was no stranger to collective violence of many forms, such as the odd execution and massacres of small communities, as well as armed conflicts. For instance, we recently reported on an analysis of human remains from 11 individuals recovered from El Mirador Cave in Spain, showing evidence of cannibalism—likely the result of a violent episode between competing Late Neolithic herding communities about 5,700 years ago. Microscopy analysis revealed telltale slice marks, scrape marks, and chop marks, as well as evidence of cremation, peeling, fractures, and human tooth marks.

This indicates the victims were skinned, the flesh removed, the bodies disarticulated, and then cooked and eaten. Isotope analysis indicated the individuals were local and were probably eaten over the course of just a few days. There have been similar Neolithic massacres in Germany and Spain, but the El Mirador remains provide evidence of a rare systematic consumption of victims.

Per the authors of this latest study, during the late Middle Neolithic, the Upper Rhine Valley was the likely site of both armed conflict and rapid cultural upheaval, as groups from the Paris Basin infiltrated the region between 4295 and 4165 BCE. In addition to fortifications and evidence of large aggregated settlements, many skeletal remains from this period show signs of violence.

Friends or foes?

Overhead views of late Middle Neolithic violence-related human mass deposits of the Alsace region, France

Overhead views of late Middle Neolithic violence-related human mass deposits in Pit 124 of the Alsace region, France. Credit: Philippe Lefranc, INRAP

Archaeologist Teresa Fernandez-Crespo of Spain’s Valladolid University and co-authors focused their analysis on human remains excavated from two circular pits at the Achenheim and Bergheim sites in Alsace in northwestern France. Fernandez-Crespo et al. examined the bones and found that many of the remains showed signs of unhealed trauma—such as skull fractures—as well as the use of excessive violence (overkill), not to mention quite a few severed left upper limbs. Other skeletons did not show signs of trauma and appeared to have been given a traditional burial.

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A geothermal network in Colorado could help a rural town diversify its economy


Town pitches companies to take advantage of “reliable, cost-effective heating and cooling.”

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.

Hayden, a small town in the mountains of northwest Colorado, is searching for ways to diversify its economy, much like other energy communities across the Mountain West.

For decades, a coal-fired power plant, now scheduled to shut down in the coming years, served as a reliable source of tax revenue, jobs, and electricity.

When town leaders in the community just west of Steamboat Springs decided to create a new business park, harnessing geothermal energy to heat and cool the buildings simply made sense.

The technology aligns with Colorado’s sustainability goals and provides access to grants and tax credits that make the project financially feasible for a town with around 2,000 residents, said Matthew Mendisco, town manager.

“We’re creating the infrastructure to attract employers, support local jobs, and give our community reliable, cost-effective heating and cooling for decades to come,” Mendisco said in a statement.

Bedrock Energy, a geothermal drilling startup company that employs advanced drilling techniques developed by the oil and gas industry, is currently drilling dozens of boreholes that will help heat and cool the town’s Northwest Colorado Business District.

The 1,000-feet-deep boreholes or wells will connect buildings in the industrial park to steady underground temperatures. Near the surface the Earth is approximately 51° F year round. As the drills go deeper, the temperature slowly increases to approximately 64° F near the bottom of the boreholes. Pipes looping down into each well will draw on this thermal energy for heating in the winter and cooling in the summer, significantly reducing energy needs.

Ground source heat pumps located in each building will provide additional heating or cooling depending on the time of year.

The project, one of the first in the region, drew the interest of some of the state’s top political leaders, who attended an open house hosted by town officials and company executives on Wednesday.

“Our energy future is happening right now—right here in Hayden,” US Senator John Hickenlooper (D-Colo.) said in a prepared statement prior to the event.

“Projects like this will drive rural economic growth while harnessing naturally occurring energy to provide reliable, cost-effective heating and cooling to local businesses,” said US Senator Michael Bennet (D-Colo.) in a written statement.

In an interview with Inside Climate News, Mendisco said that extreme weather snaps, which are not uncommon in a town over 6,000 feet above sea level, will not force companies to pay higher prices for fossil fuels to meet energy demands, like they do elsewhere in the country. He added that the system’s rates will be “fairly sustainable, and they will be as competitive as any of our other providers, natural gas, etcetera.”

The geothermal system under construction for Hayden’s business district will be owned by the town and will initially consist of separate systems for each building that will be connected into a larger network over time. Building out the network as the business park grows will help reduce initial capital costs.

Statewide interest

Hayden received two state grants totaling $300,000 to help design and build its geothermal system.

“It wasn’t completely clear to us how much interest was really going to be out there,” Will Toor, executive director of the Colorado Energy Office, said of a grant program the state launched in 2022.

In the past few years, the program has seen significant interest, with approximately 80 communities across the state exploring similar projects, said Bryce Carter, the geothermal program manager for the state’s Energy Office.

Two projects under development are by Xcel Energy, the largest electricity and gas provider in the state. A law passed in Colorado in 2023 required large gas utilities to develop at least one geothermal heating and cooling network in the state. The networks, which connect individual buildings and boreholes into a shared thermal loop, offer high efficiency and an economy of scale, but also have high upfront construction costs.

There are now 26 utility-led geothermal heating and cooling projects under development or completed nationwide, Jessica Silber-Byrne of the Building Decarbonization Coalition, a nonprofit based in Delaware, said.

Utility companies are widely seen as a natural developer of such projects as they can shoulder multi-million dollar expenses and recoup those costs in ratepayer fees over time. The first, and so far only, geothermal network completed by a gas utility was built by Eversource Energy in Framingham, Massachusetts, last year.

Grid stress concerns heat up geothermal opportunities

Twelve states have legislation supporting or requiring the development of thermal heating and cooling networks. Regulators are interested in the technology because its high efficiency can reduce demand on electricity grids.

Geothermal heating and cooling is roughly twice as efficient as air source heat pumps, a common electric heating and cooling alternative that relies on outdoor air. During periods of extreme heat or extreme cold, air source heat pumps have to work harder, requiring approximately four times more electricity than ground source heat pumps.

As more power-hungry data centers come online, the ability of geothermal heating and cooling to reduce the energy needs of other users of the grid, particularly at periods of peak demand, could become increasingly important, geothermal proponents say.

“The most urgent conversation about energy right now is the stress on the grid,” Joselyn Lai, Bedrock Energy’s CEO, said. “Geothermal’s role in the energy ecosystem will actually increase because of the concerns about meeting load growth.”

The geothermal system will be one of the larger drilling projects to date for Bedrock, a company founded in Austin, Texas, in 2022. Bedrock, which is working on another similarly sized project in Crested Butte, Colorado, seeks to reduce the cost of relatively shallow-depth geothermal drilling through the use of robotics and data analytics that rely on artificial intelligence.

By using a single, continuous steel pipe for drilling, rather than dozens of shorter pipe segments that need to be attached as they go, Bedrock can drill faster and transmit data more easily from sensors near the drill head to the surface.

In addition to shallow, low-temperature geothermal heating and cooling networks, deep, hot-rock geothermal systems that generate steam for electricity production are also seeing increased interest. New, enhanced geothermal systems that draw on hydraulic fracturing techniques developed by the oil and gas industry and other advanced drilling methods are quickly expanding geothermal energy’s potential.

“We’re also very bullish on geothermal electricity,” said Toor, of the Colorado Energy Office, adding that the state has a goal of reducing carbon emissions from the electricity sector by 80 percent by 2030. He said geothermal power that produces clean, round-the-clock electricity will likely play a key role in meeting that target.

The University of Colorado, Boulder, is currently considering the use of geothermal energy for heating, cooling, and electricity production and has received grants for initial feasibility studies through the state’s energy office.

For town officials in Hayden, the technology’s appeal is simple.

“Geothermal works at night, it works in the day, it works whenever you want it to work,” Mendisco said. “It doesn’t matter if there’s a giant snowstorm [or] a giant rainstorm. Five hundred feet to 1,000 feet below the surface, the Earth doesn’t care. It just generates heat.”

Photo of Inside Climate News

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Using pollen to make paper, sponges, and more

Softening the shell

To begin working with pollen, scientists can remove the sticky coating around the grains in a process called defatting. Stripping away these lipids and allergenic proteins is the first step in creating the empty capsules for drug delivery that Csaba seeks. Beyond that, however, pollen’s seemingly impenetrable shell—made up of the biopolymer sporopollenin—had long stumped researchers and limited its use.

A breakthrough came in 2020, when Cho and his team reported that incubating pollen in an alkaline solution of potassium hydroxide at 80° Celsius (176° Fahrenheit) could significantly alter the surface chemistry of pollen grains, allowing them to readily absorb and retain water.

The resulting pollen is as pliable as Play-Doh, says Shahrudin Ibrahim, a research fellow in Cho’s lab who helped to develop the technique. Before the treatment, pollen grains are more like marbles: hard, inert, and largely unreactive. After, the particles are so soft they stick together easily, allowing more complex structures to form. This opens up numerous applications, Ibrahim says, proudly holding up a vial of the yellow-brown slush in the lab.

When cast onto a flat mold and dried out, the microgel assembles into a paper or film, depending on the final thickness, that is strong yet flexible. It is also sensitive to external stimuli, including changes in pH and humidity. Exposure to the alkaline solution causes pollen’s constituent polymers to become more hydrophilic, or water-loving, so depending on the conditions, the gel will swell or shrink due to the absorption or expulsion of water, explains Ibrahim.

For technical applications, pollen grains are first stripped of their allergy-inducing sticky coating, in a process called defatting. Next, if treated with acid, they form hollow sporopollenin capsules that can be used to deliver drugs. If treated instead with an alkaline solution, the defatted pollen grains are transformed into a soft microgel that can be used to make thin films, paper, and sponges. Credit: Knowable Magazine

This winning combination of properties, the Singaporean researchers believe, makes pollen-based film a prospect for many future applications: smart actuators that allow devices to detect and respond to changes in their surroundings, wearable health trackers to monitor heart signals, and more. And because pollen is naturally UV-protective, there’s the possibility it could substitute for certain photonically active substrates in perovskite solar cells and other optoelectronic devices.

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Mammals that chose ants and termites as food almost never go back

Insects are more influential than we realize

By showing that ant- and termite-based diets evolved repeatedly, the study highlights the overlooked role of social insects in shaping biodiversity. “This work gives us the first real roadmap, and what really stands out is just how powerful a selective force ants and termites have been over the last 50 million years, shaping environments and literally changing the face of entire species,” Barden said.

However, according to the study authors, we still do not have a clear picture of how much of an impact insects have had on the history of life on our planet. Lots of lineages have been reshaped by organisms with outsize biomass—and today, ants and termites have a combined biomass exceeding that of all living wild mammals, giving them a massive evolutionary influence.

However, there’s also a flip side. Eight of the 12 myrmecophagous origins are represented by just a single species, meaning most of these lineages could be vulnerable if their insect food sources decline. As Barden put it, “In some ways, specializing in ants and termites paints a species into a corner. But as long as social insects dominate the world’s biomass, these mammals may have an edge, especially as climate change seems to favor species with massive colonies, like fire ants and other invasive social insects.”

For now, the study authors plan to keep exploring how ants, termites, and other social insects have shaped life over millions of years, not through controlled lab experiments, but by continuing to use nature itself as the ultimate evolutionary archive. “Finding accurate dietary information for obscure mammals can be tedious, but each piece of data adds to our understanding of how these extraordinary diets came to be,” Vida argued.

Evolution, 2025. DOI: 10.1093/evolut/qpaf121 (About DOIs)

Rupendra Brahambhatt is an experienced journalist and filmmaker. He covers science and culture news, and for the last five years, he has been actively working with some of the most innovative news agencies, magazines, and media brands operating in different parts of the globe.

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China’s Guowang megaconstellation is more than another version of Starlink


“This is a strategy to keep the US from intervening… that’s what their space architecture is designed to do.”

Spectators take photos as a Long March 8A rocket carrying a group of Guowang satellites blasts off from the Hainan commercial launch site on July 30, 2025, in Wenchang, China. Credit: Liu Guoxing/VCG via Getty Images

Spectators take photos as a Long March 8A rocket carrying a group of Guowang satellites blasts off from the Hainan commercial launch site on July 30, 2025, in Wenchang, China. Credit: Liu Guoxing/VCG via Getty Images

US defense officials have long worried that China’s Guowang satellite network might give the Chinese military access to the kind of ubiquitous connectivity US forces now enjoy with SpaceX’s Starlink network.

It turns out the Guowang constellation could offer a lot more than a homemade Chinese alternative to Starlink’s high-speed consumer-grade broadband service. China has disclosed little information about the Guowang network, but there’s mounting evidence that the satellites may provide Chinese military forces a tactical edge in any future armed conflict in the Western Pacific.

The megaconstellation is managed by a secretive company called China SatNet, which was established by the Chinese government in 2021. SatNet has released little information since its formation, and the group doesn’t have a website. Chinese officials have not detailed any of the satellites’ capabilities or signaled any intention to market the services to consumers.

Another Chinese satellite megaconstellation in the works, called Qianfan, appears to be a closer analog to SpaceX’s commercial Starlink service. Qianfan satellites are flat in shape, making them easier to pack onto the tops of rockets before launch. This is a design approach pioneered by SpaceX with Starlink. The backers of the Qianfan network began launching the first of up to 1,300 broadband satellites last year.

Unlike Starlink, the Guowang network consists of satellites manufactured by multiple companies, and they launch on several types of rockets. On its face, the architecture taking shape in low-Earth orbit appears to be more akin to SpaceX’s military-grade Starshield satellites and the Space Development Agency’s future tranches of data relay and missile-tracking satellites.

Guowang, or “national network,” may also bear similarities to something the US military calls MILNET. Proposed in the Trump administration’s budget request for next year, MILNET will be a partnership between the Space Force and the National Reconnaissance Office (NRO). One of the design alternatives under review at the Pentagon is to use SpaceX’s Starshield satellites to create a “hybrid mesh network” that the military can rely on for a wide range of applications.

Picking up the pace

In recent weeks, China’s pace of launching Guowang satellites has approached that of Starlink. China has launched five groups of Guowang satellites since July 27, while SpaceX has launched six Starlink missions using its Falcon 9 rockets over the same period.

A single Falcon 9 launch can haul up to 28 Starlink satellites into low-Earth orbit, while China’s rockets have launched between five and 10 Guowang satellites per flight to altitudes three to four times higher. China has now placed 72 Guowang satellites into orbit since launches began last December, a small fraction of the 12,992-satellite fleet China has outlined in filings with the International Telecommunication Union.

The constellation described in China’s ITU filings will include one group of Guowang satellites between 500 and 600 kilometers (311 and 373 miles), around the same altitude of Starlink. Another shell of Guowang satellites will fly roughly 1,145 kilometers (711 miles) above the Earth. So far, all of the Guowang satellites China has launched since last year appear to be heading for the higher shell.

This higher altitude limits the number of Guowang satellites China’s stable of launch vehicles can carry. On the other hand, fewer satellites are required for global coverage from the higher orbit.

A prototype Guowang satellite is seen prepared for encapsulation inside the nose cone of a Long March 12 rocket last year. This is one of the only views of a Guowang spacecraft China has publicly released. Credit: Hainan International Commercial Aerospace Launch Company Ltd.

SpaceX has already launched nearly 200 of its own Starshield satellites for the NRO to use for intelligence, surveillance, and reconnaissance missions. The next step, whether it’s the SDA constellation, MILNET, or something else, will seek to incorporate hundreds or thousands of low-Earth orbit satellites into real-time combat operations—things like tracking moving targets on the ground and in the air, targeting enemy vehicles, and relaying commands between allied forces. The Trump administration’s Golden Dome missile defense shield aims to extend real-time targeting to objects in the space domain.

In military jargon, the interconnected links to detect, track, target, and strike a target is called a kill chain or kill web. This is what US Space Force officials are pushing to develop with the Space Development Agency, MILNET, and other future space-based networks.

So where is the US military in building out this kill chain? The military has long had the ability to detect and track an adversary’s activities from space. Spy satellites have orbited the Earth since the dawn of the Space Age.

Much of the rest of the kill chain—like targeting and striking—remains forward work for the Defense Department. Many of the Pentagon’s existing capabilities are classified, but simply put, the multibillion-dollar satellite constellations the Space Force is building just for these purposes still haven’t made it to the launch pad. In some cases, they haven’t made it out of the lab.

Is space really the place?

The Space Development Agency is supposed to begin launching its first generation of more than 150 satellites later this year. These will put the Pentagon in a position to detect smaller, fainter ballistic and hypersonic missiles and provide targeting data for allied interceptors on the ground or at sea.

Space Force officials envision a network of satellites that can essentially control a terrestrial battlefield from orbit. The way future-minded commanders tell it, a fleet of thousands of satellites fitted with exquisite sensors and machine learning will first detect a moving target, whether it’s a land vehicle, aircraft, naval ship, or missile. Then, that spacecraft will transmit targeting data via a laser link to another satellite that can relay the information to a shooter on Earth.

US officials believe Guowang is a step toward integrating satellites into China’s own kill web. It might be easier for them to dismiss Guowang if it were simply a Chinese version of Starlink, but open-source information suggests it’s something more. Perhaps Guowang is more akin to megaconstellations being developed and deployed for the US Space Force and the National Reconnaissance Office.

If this is the case, China could have a head start on completing all the links for a celestial kill chain. The NRO’s Starshield satellites in space today are presumably focused on collecting intelligence. The Space Force’s megaconstellation of missile tracking, data relay, and command and control satellites is not yet in orbit.

Chinese media reports suggest the Guowang satellites could accommodate a range of instrumentation, including broadband communications payloads, laser communications terminals, synthetic aperture radars, and optical remote sensing payloads. This sounds a lot like a mix of SpaceX and the NRO’s Starshield fleet, the Space Development Agency’s future constellation, and the proposed MILNET program.

A Long March 5B rocket lifts off from the Wenchang Space Launch Site in China’s Hainan Province on August 13, 2025, with a group of Guowang satellites. (Photo by Luo Yunfei/China News Service/VCG via Getty Images.) Credit: Luo Yunfei/China News Service/VCG via Getty Images

In testimony before a Senate committee in June, the top general in the US Space Force said it is “worrisome” that China is moving in this direction. Gen. Chance Saltzman, the Chief of Space Operations, used China’s emergence as an argument for developing space weapons, euphemistically called “counter-space capabilities.”

“The space-enabled targeting that they’ve been able to achieve from space has increased the range and accuracy of their weapon systems to the point where getting anywhere close enough [to China] in the Western Pacific to be able to achieve military objectives is in jeopardy if we can’t deny, disrupt, degrade that… capability,” Saltzman said. “That’s the most pressing challenge, and that means the Space Force needs the space control counter-space capabilities in order to deny that kill web.”

The US military’s push to migrate many wartime responsibilities to space is not without controversy. The Trump administration wants to cancel purchases of new E-7 jets designed to serve as nerve centers in the sky, where Air Force operators receive signals about what’s happening in the air, on the ground, and in the water for hundreds of miles around. Instead, much of this responsibility would be transferred to satellites.

Some retired military officials, along with some lawmakers, argue against canceling the E-7. They say there’s too little confidence in when satellites will be ready to take over. If the Air Force goes ahead with the plan to cancel the E-7, the service intends to bridge the gap by extending the life of a fleet of Cold War-era E-3 Sentry airplanes, commonly known as AWACS (Airborne Warning and Control System).

But the high ground of space offers notable benefits. First, a proliferated network of satellites has global reach, and airplanes don’t. Second, satellites could do the job on their own, with some help from artificial intelligence and edge computing. This would remove humans from the line of fire. And finally, using a large number of satellites is inherently beneficial because it means an attack on one or several satellites won’t degrade US military capabilities.

In China, it takes a village

Brig. Gen. Anthony Mastalir, commander of US Space Forces in the Indo-Pacific region, told Ars last year that US officials are watching to see how China integrates satellite networks like Guowang into military exercises.

“What I find interesting is China continues to copy the US playbook,” Mastalir said. “So as as you look at the success that the United States has had with proliferated architectures, immediately now we see China building their own proliferated architecture, not just the transport layer and the comm layer, but the sensor layer as well. You look at their their pursuit of reusability in terms of increasing their launch capacity, which is currently probably one of their shortfalls. They have plans for a quicker launch tempo.”

A Long March 6A carries a group of Guowang satellites into orbit on July 27, 2025, from the Taiyuan Satellite Launch Center in north China’s Shanxi Province. China has used four different rocket configurations to place five groups of Guowang satellites into orbit in the last month. Credit: Wang Yapeng/Xinhua via Getty Images

China hasn’t recovered or reused an orbital-class booster yet, but several Chinese companies are working on it. SpaceX, meanwhile, continues to recycle its fleet of Falcon 9 boosters while simultaneously developing a massive super-heavy-lift rocket and churning out dozens of Starlink and Starshield satellites every week.

China doesn’t have its own version of SpaceX. In China, it’s taken numerous commercial and government-backed enterprises to reach a launch cadence that, so far this year, is a little less than half that of SpaceX. But the flurry of Guowang launches in the last few weeks shows that China’s satellite and rocket factories are picking up the pace.

Mastalir said China’s actions in the South China Sea, where it has taken claim of disputed islands near Taiwan and the Philippines, could extend farther from Chinese shores with the help of space-based military capabilities.

“Their specific goals are to be able to track and target US high-value assets at the time and place of their choosing,” he said. “That has started with an A2AD, an Anti-Access Area Denial strategy, which is extended to the first island chain and now the second island chain, and eventually all the way to the west coast of California.”

“The sensor capabilities that they’ll need are multi-orbital and diverse in terms of having sensors at GEO (geosynchronous orbit) and now increasingly massive megaconstellations at LEO (low-Earth orbit),” Mastalir said. “So we’re seeing all signs point to being able to target US aircraft carriers… high-value assets in the air like tankers, AWACs. This is a strategy to keep the US from intervening, and that’s what their space architecture is designed to do.”

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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betel-nuts-have-been-giving-people-a-buzz-for-over-4,000-years

Betel nuts have been giving people a buzz for over 4,000 years

Ancient rituals and customs often leave behind obvious archaeological evidence. From the impeccably preserved mummies of Egypt to psychoactive substance residue that remained at the bottom of a clay vessel for thousands of years, it seems as if some remnants of the past, even if not all are immediately visible, have defied the ravages of time.

Chewing betel nuts is a cultural practice in parts of Southeast Asia. When chewed, these reddish nuts, which are the fruit of the areca palm, release psychoactive compounds that heighten alertness and energy, promote feelings of euphoria, and help with relaxation. They are usually wrapped in betel leaves with lime paste made from powdered shells or corals, depending on the region.

Critically, the ancient teeth from betel nut chewers are distinguishable because of red staining. So when archaeologist Piyawit Moonkham, of Chiang Mai University in Thailand, unearthed 4,000-year-old skeletons from the Bronze Age burial site of Nong Ratchawat, the lack of telltale red stains appeared to indicate that the individuals they belonged to were not chewers of betel nuts.

Yet when he sampled plaque from the teeth, he found that several of the teeth from one individual contained compounds found in betel nuts. This invisible evidence could indicate teeth cleaning practices had gotten rid of the color or that there were alternate methods of consumption.

“We found that these mineralized plaque deposits preserve multiple microscopic and biomolecular indicators,” Moonkham said in a study recently published in Frontiers. “This initial research suggested the detection potential for other psychoactive plant compounds.”

Since time immemorial

Betel nut chewing has been practiced in Thailand for at least 9,000 years. During the Lanna Kingdom, which began in the 13th century, teeth stained from betel chewing were considered a sign of beauty. While the practice is fading, it is still a part of some religious ceremonies, traditional medicine, and recreational gatherings, especially among certain ethnic minorities and people living in rural areas.

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physics-of-badminton’s-new-killer-spin-serve

Physics of badminton’s new killer spin serve

Serious badminton players are constantly exploring different techniques to give them an edge over opponents. One of the latest innovations is the spin serve, a devastatingly effective method in which a player adds a pre-spin just before the racket contacts the shuttlecock (aka the birdie). It’s so effective—some have called it “impossible to return“—that the Badminton World Federation (BWF) banned the spin serve in 2023, at least until after the 2024 Paralympic Games in Paris.

The sanction wasn’t meant to quash innovation but to address players’ concerns about the possible unfair advantages the spin serve conferred. The BWF thought that international tournaments shouldn’t become the test bed for the technique, which is markedly similar to the previously banned “Sidek serve.” The BWF permanently banned the spin serve earlier this year. Chinese physicists have now teased out the complex fundamental physics of the spin serve, publishing their findings in the journal Physics of Fluids.

Shuttlecocks are unique among the various projectiles used in different sports due to their open conical shape. Sixteen overlapping feathers protrude from a rounded cork base that is usually covered in thin leather. The birdies one uses for leisurely backyard play might be synthetic nylon, but serious players prefer actual feathers.

Those overlapping feathers give rise to quite a bit of drag, such that the shuttlecock will rapidly decelerate as it travels and its parabolic trajectory will fall at a steeper angle than its rise. The extra drag also means that players must exert quite a bit of force to hit a shuttlecock the full length of a badminton court. Still, shuttlecocks can achieve top speeds of more than 300 mph. The feathers also give the birdie a slight natural spin around its axis, and this can affect different strokes. For instance, slicing from right to left, rather than vice versa, will produce a better tumbling net shot.

Chronophotographies of shuttlecocks after an impact with a racket

Chronophotographies of shuttlecocks after an impact with a racket. Credit: Caroline Cohen et al., 2015

The cork base makes the birdie aerodynamically stable: No matter how one orients the birdie, once airborne, it will turn so that it is traveling cork-first and will maintain that orientation throughout its trajectory. A 2015 study examined the physics of this trademark flip, recording flips with high-speed video and conducting free-fall experiments in a water tank to study how its geometry affects the behavior. The latter confirmed that shuttlecock feather geometry hits a sweet spot in terms of an opening inclination angle that is neither too small nor too large. And they found that feather shuttlecocks are indeed better than synthetic ones, deforming more when hit to produce a more triangular trajectory.

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an-extinct-volcano-in-arkansas-hosts-the-only-public-diamond-mine-on-earth

An extinct volcano in Arkansas hosts the only public diamond mine on Earth

The park provides two covered pavilions with water troughs and tables for wet sifting, plus open sluice boxes with hand-operated water pumps at both ends of the field. Four shaded structures are available in the search area; however, visitors are also welcome to bring their own canopies or tents, provided they are well-secured.

The diamonds formed under extreme pressure and heat deep in the Earth’s mantle. If you find one, it will most likely look like a metallic or glassy pebble rather than a sparkly cut gem that you might picture in your mind. The volcanic soil also contains amethyst, garnet, jasper, agate, and various types of quartz (and you can keep those, too).

The largest diamond found in the United States came from this field—the 40.23-carat Uncle Sam diamond, discovered in 1924 before the land became a state park. In September 2021, California visitor Noreen Wredberg found a 4.38-carat yellow diamond after searching for two hours, and in 2024, a visitor named Julien Navas found a 7.46-carat diamond at the park.

The park received over 180,000 visitors in 2017, who found 450 certified diamonds of various colors. Of the reported diamond finds, 299 were white, 72 were brown, and 74 were yellow.

Park staff told Mays that visitors find one or two diamonds daily, so “keep your expectations in check,” she writes. Most diamonds discovered are about the size of a paper match head, while a one-carat diamond is roughly the size of a green pea. But even tiny diamonds carry the thrill of discovery. Park staff provide free identification services, examining finds under loupes and confirming whether that glassy pebble is quartz or something more valuable.

A family experience

For those wanting to join the thousands who visit each year, the park makes it affordable. Admission costs $15 for adults, $7 for children ages 6–12. You can camp overnight at the park and return to the field at dawn. During summer months, the park operates a small water park—an acknowledgment that diamond hunting in Arkansas can be brutal, with a heat index exceeding 110° Fahrenheit.

Sometimes rain turns the field into mud, which experienced searchers prefer because it makes diamonds easier to spot—but it can make for a messy adventure. As Mays put it, “Most visitors leave with a handful of interesting rocks, some newfound knowledge, and an urgent need for a long shower.”

If you don’t find any diamonds at the park, don’t despair—you could still potentially buy a $200,000 diamond-making machine on Alibaba.

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