One week ago, more than 200 miles above the Earth, a refrigerator-size satellite making its way toward an attempted rescue of NASA’s $500 million Swift gamma-ray observatory suddenly spun out of control.

It didn’t look good. The spacecraft, named Link, was rotating on multiple axes, rendering it unable to maintain a reliable communications link with the ground and complicating efforts to arrest the spin. Two of the satellite’s three reaction wheels, used for pointing, also stopped working. Through sporadic radio contact, engineers discovered a problem with some of the spacecraft’s cold gas thrusters used for finer attitude control.

The Link satellite is built, owned, and operated by Katalyst Space Technologies, a satellite servicing startup that won a $30 million contract from NASA to fly up to the Swift observatory, grab onto it, and boost its orbit before succumbing to aerodynamic drag and burning up int he atmosphere.

The clock is ticking. In a few months, Swift will be too low for Katalyst to complete the rescue. This is the first time NASA has contracted with a commercial company to service one of its satellites. The space agency gave Katalyst less than a year to put the mission together. The Link satellite launched July 3 to begin the pursuit of Swift, and the mission proceeded mostly according to plan until last Saturday.

“When this happened, it was during one of the passes without comms,” said Ghonhee Lee, CEO of Katalyst, said in an interview with Ars. “We were, immediately prior, in a very stable configuration.”

Katalyst’s ground team, working from a control center near Denver, hurried to find a fix and recover the Link satellite. The good news was the spacecraft’s other systems remained healthy, including its power supply, three xenon-fueled electric thrusters, and the rendezvous and robotics hardware the Link satellite needs to capture Swift.

Keeping at it

Ars spoke with Lee, Katalyst’s chief executive, on Friday afternoon as the company’s ground team worked to stabilize the spacecraft. The first step involves using the satellite’s plasma engines to gradually slow the spin. The engines are primarily designed for orbit-raising, but they’re also suitable for attitude control because they can vector their thrust with a two-axis gimbal.

https://arstechnica.com/space/2026/08/heres-how-engineers-plan-to-save-the-satellite-sent-to-save-nasas-swift-mission/

In this case, the team made a couple of key variations. The first is that it mostly performed what are called Clifford gates, which are relatively easy to simulate on classical hardware. But it sprinkled in a few non-Clifford gates (specifically T gates) of a specific type chosen in part because they are less prone to error. “Z rotations (including T gates) are special in our hardware: they are implemented by virtual frame tracking and do not add extra noise,” the paper said.

But the T gates also help ensure that this is especially hard to simulate on a classical computer. “It’s got a stronger complexity argument because of the [T gates], which you can prove on average is exponentially hard to sample for a classical computer,” Gambetta told Ars. That will make it very challenging for classical algorithms to catch up.

The work also linked in a few additional qubits around the periphery of those used for the algorithm, arranged so that gentle measurements performed during the operations could detect whether errors had occurred; if they were detected, the results were discarded. (Note that this would also throw out valid results that were flagged by an erroneous read of these additional qubits.)

The result was an algorithm that “combines the broad output statistics of hard sampling problems with circuit structure that can be exploited for error detection and fidelity certification,” the team said.

The last of the new results comes from quantum software developer Algorithmiq, which used an algorithm similar to the one in Google’s “quantum echoes” work. A set of gates first alters a quantum system, after which the process is reversed. Additional operations performed during the reversal prevent the system from returning to its original state—instead, the noise creates an imperfect “echo” of the forward process. As with one of the earlier works, attempts to simulate this on classical hardware require some simplification, and different simplification methods yield different results. By its nature, then, the problem is beyond the reach of classical hardware.

https://arstechnica.com/science/2026/07/if-a-quantum-computer-outperforms-normal-ones-can-you-tell-if-its-right/

For qubits, the traps are far smaller and serve to hold a single electron in place. Critically, they can be manufactured; with the right wiring, electromagnetic interactions can trap a single electron in a small patch of silicon. Once trapped, the electron’s spin, which can be up, down, or a superposition of the two, can be used as a qubit. While this technology can scale easily—we’re very good at putting wiring into silicon at scale—electron spins are hard to keep stable and are typically controlled via microwaves, requiring a separate control system.

But “typically” doesn’t mean “always,” and HRL is describing a different tech. It requires three separate quantum dots, each holding an electron, with the surrounding electronics controlling how much the spins of these three electrons can interact. That’s critical because, under certain conditions, no two electrons can have the same spin. This explains why atomic orbitals fill up the way they do, with each energy level holding just a pair, one spin-up, the other spin-down. Enabling them to interact can alter their spins.

To do operations on this kind of qubit, you simply need to control which electrons are interacting and to what extent. That is controlled electronically, allowing us to eliminate microwaves entirely. Everything is handled via wiring, eliminating the need for lots of microwave-carrying cabling into the refrigeration system that keeps the hardware near absolute zero.

HRL spends much of the paper describing its control system, which sits at an intermediate level of refrigeration and consists of a traditional processor optimized for low-temperature and low-power operations, consuming less than 3.5 watts despite being manufactured on a 130 nm process. Instructions for operating the qubits are compiled elsewhere, then loaded into the controller, after which it operates autonomously. Communications with the chip that holds the qubits are handled by a superconducting ribbon cable.

https://arstechnica.com/science/2026/07/quantum-computing-roundup-still-more-technologies-making-waves/

The authors’ model, named pathway multinomial logit or “pathway MNL,” does not reveal causal effects, they caution, but the associations they uncover are informative for museum professionals.

Multimedia guide users largely visited recommended artworks in the suggested order. Lisa van den Bos, product manager for digital education at the museum while the study was underway, expressed surprise that even subtle ordering changes on the guide impacted traffic patterns. “We actually have a lot of power in how we move people through,” she said.

Visitors sought variety in time period and size but consistency in subject and theme, the team found. Time pressure also affected choices; as time elapsed within a given visit, people were more likely to prioritize seeing masterpieces.

Perhaps surprisingly, the data revealed that congestion can increase engagement. “When there are more people, at least up to a certain number…people are more likely to go and view artworks that they probably wouldn’t have seen,” said Deshmane. Crowding around a painting may also be seen as a signal of quality.

Rearranging permanent collections can be tricky due to space or thematic constraints, but museums can often experiment with exhibition or gallery spaces, where shorter time frames and lower infrastructural requirements allow easier changes, said Deshmane.

Rather than actually moving pieces, the researchers used a simulation to generate new layouts and predict likely visitor reactions. Based on their simulations, they found that moving highly attractive art from leaky spots (e.g., stairs or lifts) and strategically swapping pieces could lead to visitors seeing more art—and staying for longer—without undermining curatorial aims. Additionally, data-informed planning of digital layouts, even without accompanying physical moves, may help visitors understand art through new perspectives, said Gundy van Dijk, the museum’s head of education and interpretation.

https://arstechnica.com/culture/2026/07/with-help-from-data-art-museums-are-reframing-the-visitor-experience/

Here, its solution is grand in scope. It views the maker community, which is mostly interested in scratching personal itches, as a sign that the US public wants to make things again. The SNGA authors figure that they would be perfectly happy making things for science. “Establish national fellowships for skilled craftspeople,” they suggest, “practitioner-in-residence programs embedding machinists and technicians alongside Ph.D. researchers, and portable industry-recognized credentials in advanced manufacturing and lab techniques.”

It’s unclear what these machinists will be doing with the researchers. But the results will be glorious: “By rebuilding the link between science and hands-on craft, federal leadership can ensure that the economic returns of discovery, including the jobs, supplier networks, and process knowledge encoded in the hands of workers, accrue to Americans.”

Its example is Detroit in its heyday, although that seems to have been a period of engineering refinements that lacked a notable scientific component. And it’s unclear what scientific research center the SNGA associates with Detroit at that time.

Are there some fields that can be revolutionized by things like a 3D printer and a bit of time with the maker community? Robotics seems like an obvious choice; developmental biology does not.

Elsewhere, the report returns to the familiar claim that regulations are also stifling the potential for science-driven commercial innovation. The only specific area that’s cited, however, is nuclear power: “nuclear energy stalled in America not because the physics failed, but because regulatory choices over the past half-century made building uneconomical.” That is not a realistic reading of the history, as there is little indication that regulations are the primary cause of the massive delays and cost overruns that plague nuclear plant construction.

Political grievance and Silicon Valley

The complaints about regulations are one of the many cases where SNGA descends into political and cultural grievance. The most obvious case is where it detours to grumble about the role of the scientific community in the arguments over COVID school closures, but there are many additional ones.

https://arstechnica.com/science/2026/07/white-house-report-says-trump-can-usher-in-a-new-golden-age-of-science/

There have been numerous accounts in recent years of orcas ramming boats—and sometimes sinking them. Scientists believe this may be a form of culturally learned behavior passed down through generations. Now we have fresh examples: orcas in the Gulf of California were filmed teaming up to ram sunfish with so much force that the carcasses exploded into small fragments. While orcas have been known to use force to remove flesh from prey, this is something different, according to a new paper published in the journal Frontiers in Ethology.

“We think this may help younger orcas feed more easily, or it could also just be for fun,” said co-author Kathryn Ayres of Beneath The Waves, a nonprofit organization promoting ocean health. “Orcas are known for playing with their food.”

Orcas engage in cooperative hunting strategies that can involve striking or killing animals—sometimes eating their prey, sometimes not—so the behavior could be described as social interaction, play, or practice as a mode of social learning. Orcas have been observed ramming whale sharks as another orca held the prey steady. Other cooperative strategies include herding mobile rays, blocking an escape path while hunting white sharks, and deliberately producing waves to bump penguins off ice floes.

When hunting species like sunfish, orcas typically rely on a three-pronged strategy. First, an orca will target the pectoral fins, then slash the sunfish across its body to remove the viscera. After that, the orca will use its beak to get at the remaining tissue. The newly observed “ram-to-fragment” behavior might represent a more sophisticated version of that basic strategy.

Play with your food

The first instance occurred in July 2024 off the coast of San Jose del Cabo in Mexico. A tourism operator filmed three adult female orcas, one male, and one juvenile catching and eating a spine-tail devil ray. Just after, the same operator filmed one of the adult females holding the carcass of a sunfish in her mouth. The sunfish had a large lateral wound, so the viscera had likely already been removed. The male orca then charged at the carcass, with the female releasing it just before impact. There was an audible sound upon impact as the carcass fragmented and bits of flesh dispersed in the water. The juvenile orca proceeded to eat the smaller fragments while the adults fed on what remained of the split-open body.

https://arstechnica.com/science/2026/07/orcas-team-up-to-ram-sunfish-until-they-explode/

A photon is a single particle of light, and under normal circumstances, it can’t be divided. But a photon is also not a particle, in the sense that it does not have a specific location. Instead, it is an extended object.

So if a photon is only partway through the process of reflecting from a perfect mirror and you yank the mirror away, what happens? The answer, from a trio of Norwegian physicists, turns out (arxiv.org link) to be more complex than I expected.

A photon divided?

Let’s first talk briefly about dividing and combining photons. If this were a common experience in our lives, then shining a single color of light through a piece of glass or reflecting it from a surface might cause photons to divide or combine. This would lead to an amazing array of colors: Our universe would be the most fantastic and legal LSD trip you could imagine. But this doesn’t generally happen, hence LSD.

What does happen is that photons can divide and combine under the right circumstances—essentially, the medium through which the light travels has to change in response to the light. This can lead to a rainbow of colors from a single color source.

Technically, we would say that the light interactions we see around us are linear, and the combination/division of photons is a nonlinear process. Typically, to overcome that nonlinearity, you need either a very sensitive medium or a very high-intensity light source, like a laser.

The sudden removal of the mirror while a photon is reflecting is not nonlinear in the way that I would normally think about it. But if you give it more than a moment’s thought, it’s clearly a nonlinear event. This line of thinking is obscured by how we think about single photons at mirrors, though, as I will illustrate below.

https://arstechnica.com/science/2026/07/what-happens-when-you-try-to-chop-a-photon-in-half/

When Mount Vesuvius erupted in 79 CE, it spewed molten rock, pumice, and hot ash over the cities of Pompeii and Herculaneum, killing thousands of people. It’s one of the most famous natural disasters in human history, so naturally there have been countless documentaries about Pompeii (and at least one popular song). But only one features actor Tom Hiddleston taking on the role of a “time detective” to bring the people of Pompeii to vivid life. That would be National Geographic’s new three-part docuseries, Pompeii: Out of Time.

The Marvel connection made Out of Time happen. Executive producer Kevin Wright was also a producer on the Disney+ series Loki, which included a scene where Hiddleston’s Loki travels through time to visit Pompeii. Hiddleston also studied classics at Cambridge University and had visited the Pompeii archaeological site as a teenager, which the Marvel star attributes to indirectly influencing his career path into acting.

“There is just a passion to the way Tom tells stories that’s infectious,” Wright told Ars. “We knew that if we could capture that and put it into [the series], it might interest people who wouldn’t normally want to watch a documentary about Pompeii. “

The docuseries combines the usual historical and scientific facts with Hiddleston’s personal journey of discovery. He homes in on three people in particular and follows them over the city’s final 24 hours to discover whether or not they survived: a teenage boy, a local businesswoman, and a Praetorian guard. Stilted re-enactments are replaced with scripted dramatic scenes and high production values to make it all feel more cinematic. It’s an unusual approach, if only because we’re so conditioned to what a documentary “should” be. But the blended approach makes for a powerful experience.

“We felt we could use the imagination to make a more human story. This isn’t just ancient history; these were real people, and their lives were not dramatically different than ours even though they lived 2,000 years ago,” said Wright. “One of the most freeing moments was when we came to this idea of ‘historia,’ the merging of imagination and historical fact, and that ‘storytelling’ and ‘history’ in Latin are the same word. It was Hiddleston who put us onto that. When we went to our historians, our experts, with that word, we were met with nothing but enthusiasm. There seems to be a real movement in archaeology of, ‘This is how you have to approach it now.’”

https://arstechnica.com/science/2026/07/tom-hiddleston-tracks-possible-pompeii-survivors-in-new-docuseries/

The Space Force originally estimated the Lane 1 launch providers would compete for at least 30 task orders over a five-year period. Officials put a ceiling of $5.6 billion on the Lane 1 contract to cover these 30 missions. The Space Force capped the Lane 2 contract at $13.7 billion last year, a number officials thought was sufficient to cover an estimated 54 launches projected for procurement through 2029.

But things have changed rapidly. In April, Space Systems Command said it had identified 25 additional Lane 2 missions on top of the 54 included in the original contract just one year before. Now, the Space Force is tripling the maximum value for the Lane 1 contract. The service has not said how many more missions it expects to order in Lane 1 beyond the initial estimate of 30.

With Friday’s announcement, the combined maximum value of Lane 1 and Lane 2 has reached more than $30 billion, and the number is likely to climb again. Space Force officials have not publicly identified exactly what missions they plan to add to each of the NSSL contracts. But there are a few obvious programs driving the military’s rising launch demand.

One is the Space Force’s recent award of multibillion-dollar contracts to SpaceX for the deployment of numerous satellites for the Pentagon’s Space Data Network and Airborne Moving Target Indicator programs. The SDN and AMTI satellite constellations will provide global connectivity and targeting information for US forces. Another is Golden Dome, the Trump administration’s proposed missile defense shield, which is expected to include an untold number of space-based missile warning sensors and space-based interceptors.

The Trump administration requested $71.1 billion for the Space Force in fiscal year 2027, up from approximately $40 billion allocated for fiscal year 2026. The House Appropriations Committee’s draft 2027 budget for the Pentagon includes $55.5 billion for the Space Force, somewhat less than the White House’s request. The Senate has not released its Pentagon budget bill.

https://arstechnica.com/space/2026/07/the-space-force-is-now-seeking-to-buy-up-to-30-billion-in-rocket-launches/

This view of the payload deck of the Vikram-1 rocket’s upper stage was captured moments after orbital insertion Saturday. The rocket deployed two small CubeSats and hosted several more payloads that remained attached to the upper stage.

Credit: Skyroot Aerospace

Skyroot’s breakthrough launch comes as India’s government, led by Prime Minister Narendra Modi, seeks to supercharge the country’s space industry. India has long had a robust space program, with government-developed rockets such as the Polar Satellite Launch Vehicle and the larger LVM3 often attracting commercial customers from the United States and Europe. India became the fourth country to successfully land a spacecraft on the Moon in 2023, and is working on an oft-delayed human-rated crew capsule to fly astronauts to low-Earth orbit.

Modi has told the Indian space industry to increase its annual launch total from about five launches per year to 50 before the end of the decade. The prime minister called Chandana and congratulated the Skyroot team after Saturday’s launch.

“This is a defining moment in India’s space journey,” Modi said in a statement. “The growing participation of our private sector is opening new frontiers and accelerating innovation. This achievement will encourage countless youngsters to dream bigger and innovate fearlessly.”

Chandana, a former engineer at India’s space agency, founded Skyroot in 2018 with another ISRO scientist, Naga Bharath Daka. They decided to focus on developing a solid-fueled launcher first, optimizing for what Chandana described as the lowest development time and the lowest cost per launch. “We wanted to get to an orbital launch vehicle in a few years,” Chandana told Ars.

“It’s a test launch” he said at the time. “Statistically, the first launch from a private company almost always fails. It’s very difficult to succeed with all new systems. But I think we have done everything we can do to ensure the first launch goes well.”

Indeed, the first launch went very well, exceeding all expectations. A second Vikram-1 launch could happen before the end of the year, Chandana said.

“This is a 100 percent designed in India rocket, a 100 percent made in India rocket, built by 100 percent Indian people, for India and for the world,” Chandana said after the launch Saturday. “This was a historic moment for India, but also a very proud moment for the global space sector because the world needs more access to space.”

https://arstechnica.com/space/2026/07/indias-first-privately-developed-rocket-reaches-orbit-on-dramatic-debut-launch/