Category: 7. Science

Fighting off pathogens is a tour de force that must happen with speed and precision. A team of researchers at CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, and at Medical University of Vienna (MedUni Vienna) has investigated how macrophages master this challenge.

Led by Christoph Bock, PhD, CeMM principal investigator and professor at MedUni Vienna, and Matthias Farlik, PhD, principal investigator at the MedUni Vienna, the researchers’ newly reported study offers a time-resolved analysis of the molecular processes that unfold when macrophages encounter various pathogens and infection-linked stimuli. To achieve this, the team developed a new method in mice that combines CRISPR gene editing and machine learning, and which identified key regulators of macrophage responses to the six different stimuli, including infectious pathogens, pathogen-derived stimuli, and pro-inflammatory cytokines.

“This study combined epigenome and transcriptome time series profiling with high-content CRISPR screening and integrative computational analysis in order to dissect the pathogen response in murine macrophages,” the team wrote in their paper in Cell Systems, which is titled “Integrated time-series analysis and high-content CRISPR screening delineate the dynamics of macrophage immune regulation.” They further concluded, “To our knowledge, this is the first study that combines epigenome/transcriptome time-series profiling with high-content CRISPR screening, demonstrated here for the dissection of gene regulation in mouse macrophages.”

“Innate immunity is critical for protecting the body against pathogens,” the authors wrote. “Macrophages are among the first immune cells to respond to invading pathogens, which they sense via pattern recognition receptors.”

Macrophages are also messengers, releasing various signals to recruit other immune cells, triggering inflammation, and presenting digested fragments of pathogens on their surface, guiding the adaptive immune system to develop long-term immunity. Macrophages encountering a pathogen are under immense pressure. If they react too late or not decisively enough, an infection may become fatal. But an overshooting immune response is equally damaging. Within a very short time, a tailored immune response must be initiated, including cascades of biochemical reactions triggered, thousands of genes activated, and an arsenal of substances produced—each response tailored to the specific pathogen encountered.

The authors further explained in their paper, “Detection of pathogen-associated molecular patterns (PAMPs) activates signaling cascades and transcriptional regulators such as NF-κB, IRF, and AP-1. These regulatory proteins orchestrate expression of their target genes over the course of the pathogen response and during the subsequent return to homeostasis.”

To understand how macrophages coordinate this multitude of tasks, Bock, Farlik and colleagues exposed murine macrophages to various immune stimuli that mimic bacterial or viral infections. They tracked the changes inside the cells by measuring gene activity and DNA accessibility every few hours, establishing a molecular timeline of how the regulatory programs unfold step by step.

Next, the team identified regulatory proteins that orchestrate these programs, using CRISPR genome editing to produce hundreds of gene knockouts, and single-cell RNA sequencing to characterize the genetically perturbed cells. “We investigated six immune stimuli (Listeria, LCMV, Candida, LPS, IFN-β, and IFN-γ) over a dense multiomics time course and performed high-throughput functional dissection of the macrophage response to Listeria using a combined CROP-seq and CITE-seq method,” they wrote.

This innovative method uncovered a network of several dozen regulators that share the responsibility of triggering the most appropriate immune response. The identified regulators include many that would be expected, such as the JAK-STAT signaling pathway, but also identified splicing factors and chromatin regulators that may have far less well understood roles in immune regulation. “We identified new roles of transcription regulators such as Spi1/PU.1 and JAK-STAT pathway members in immune cell homeostasis and response to pathogens,” the investigators commented. “Macrophage activity was modulated by splicing proteins SFPQ and SF3B1, histone acetyltransferase EP300, cohesin subunit SMC1A, and mediator complex proteins MED8 and MED14.”

Senior author Bock said, “It is impressive how much complexity there is in this ancient part of our immune system, which we share with sponges, jellyfish, and corals. Thanks to the advances in CRISPR screening technology, we can systematically study the underlying regulatory programs.”

In their paper the team stated in summary, “…this study establishes a time-resolved regulatory map of pathogen response in macrophages, and it describes a broadly applicable method for dissecting immune-regulatory programs through integrative time-series analysis and high-content CRISPR screening.”

There’s a giant blob of incredibly hot rock beneath New Hampshire — and it may be part of the reason the Appalachian Mountains are still standing tall, according to new research. It has, however, been slowly moving and is on course for New York in the next 15 million years.

This hot rock blob, called the Northern Appalachian Anomaly, or NAA, sits about 124 miles (200 kilometers) beneath the mountain range in New England and measures between 217 and 249 miles (350 and 400 kilometers) wide. It is in the asthenosphere, or the semi-molten layer of Earth’s upper mantle, and is considered a thermal anomaly because its temperature is hotter than its surroundings.

Rock formations in this part of the Earth’s interior are unusual, and scientists previously thought it formed when the North American continent broke apart from northwest Africa 180 million years ago.

But new research, published July 29 in the journal Geology, suggests the anomaly is linked to when Greenland and North America separated 80 million years ago.

At a rate of 12.4 miles (20 kilometers) per 1 million years, the thermal anomaly has migrated about 1,118.5 miles (1,800 kilometers) from its point of origin as Earth’s crust ruptured near the Labrador Sea between Canada and Greenland.

The hot rock mass has long been a puzzling feature of North American geology, said lead study author Tom Gernon, professor of Earth science at the University of Southampton in the UK.

“It lies beneath part of the continent that’s been tectonically quiet for 180 million years, so the idea it was just a leftover from when the landmass broke apart never quite stacked up,” Gernon said in a statement.

Instead, the rock blob could help explain why ancient mountains such as the Appalachians haven’t eroded away as much as expected over time.

“Heat at the base of a continent can weaken and remove part of its dense root, making the continent lighter and more buoyant, like a hot air balloon rising after dropping its ballast,” Gernon said. “This would have caused the ancient mountains to be further uplifted over the past few million years.”

New insights about the blob could help scientists better understand other similar geological abnormalities across the globe — including one beneath north-central Greenland that may be a sibling of the Northern Appalachian Anomaly— as well as the impacts these rare features could have on Earth’s surface.

To explain the rock blob’s origin and current position, the scientists used “mantle wave” theory, which they proposed in previous research.

The idea is similar to the process that unfolds inside a lava lamp. After continents rift, or break apart, hot, dense rock detaches from the base of tectonic plates in blobs, which generate waves beneath Earth’s crust.

When continents stretch and split, space opens beneath the breaking point and is rapidly filled with semi-molten asthenosphere, Gernon said. The upwelling material rubs against the newly broken edge of the colder continent, causing the material to cool, grow dense and sink — a process called edge-driven convection. The hotter mantle substance creates a warm region known as a thermal anomaly, said study coauthor Sascha Brune, professor at the GFZ Helmholtz Centre for Geosciences in Potsdam, Germany.

“This sudden movement disturbs the edge of the continent’s root, triggering a chain reaction,” Gernon said. “Much like falling dominoes, blobs of the root begin to drip downward one after another — a process driven by gravity known as Rayleigh-Taylor instability. These ‘drips’ migrate inland over time, away from the rift. We think this same process might explain unusual seismic patterns beneath the Appalachians.”

The convective rock currents continue to flow slowly and ripple over millions of years, leading to rare volcanic eruptions that bring diamonds to Earth’s surface or help uplift mountains, the researchers found.

“The idea that rifting of continents can cause drips and cells of circulating hot rock at depth that spread thousands of kilometres inland makes us rethink what we know about the edges of continents both today and in Earth’s deep past,” study coauthor Dr. Derek Keir, associate professor of Earth science at the University of Southampton, said in a statement.

For its research, the team used seismic waves to image Earth’s interior, as well as geodynamic simulations and tectonic plate reconstructions, to track the Northern Appalachian Anomaly’s origin point.

“If we trace the wave’s path backwards from where it is now,” Gernon said, “it would have originated below the Labrador Sea rift margin at the time when the rift was forming and close to the point of continental breakup.”

Maureen D. Long, the Bruce D. Alexander ’65 Professor and Chair of Yale University’s department of Earth and planetary sciences, and her team have several active research projects studying the North Appalachian Anomaly.

While Long was not involved in this study, her research group is collecting new seismic data from arrays of seismometers in the region to capture more detailed images of the rock blob. The new model shared in the recently published study will help Long and her colleagues think through all the possible ways to interpret the images they capture, she said.

“It’s exciting to see a new and creative model proposed for the origin of the Northern Appalachian Anomaly, which still remains poorly understood despite much study,” Long wrote in an email. “While I don’t think any of our conceptual models for how the NAA might have formed, including this new one, does a perfect job of explaining the full range of observations, it’s great to see some new thinking on this that brings some novel ideas to the table.”

Looking forward, the team said its modeling shows that the center of the anomaly will pass beneath New York within the next 15 million years.

“What the anomaly will look like in the future is a really interesting puzzle for geologists to think about,” Long said, “but it’s not going to have any foreseeable impact on human infrastructure or on our daily lives.”

But what does the movement mean for the Appalachian Mountains? The range, formed when the North American Plate collided with other tectonic plates during the Paleozoic Era, between 541 million and 251.9 million years ago, experienced a new growth spurt when the supercontinent Pangaea broke apart around 180 million years ago, Gernon said.

The rock blob may have also contributed to uplifting the mountains during the Cenozoic Era over the last 66 million years, according to the new study.

“It is likely that this anomaly has played some role in shaping the geologic structures that lie above it,” Long said. “For example, several studies have suggested that the lithosphere (the crust and the uppermost mantle, which makes up the tectonic plate) above the NAA is particularly thin, and it’s likely that the anomaly has played a role in thinning the plate above it.”

Once the rock blob moves, the crust beneath the Appalachians would likely settle and stabilize once more, Gernon said.

“In the absence of further tectonic or mantle-driven uplift, erosion would continue to wear down the mountains, gradually lowering their elevation,” Gernon said.

Additionally, the team believes the breakup of Greenland and North America may have created another thermal anomaly that emerged from the opposite side of the Labrador Sea. This second anomaly adds to a flow of heat at the base of a thick continental ice sheet, influencing the movement and melting of the ice, the study authors said.

“Even though the surface shows little sign of ongoing tectonics, deep below, the consequences of ancient rifting are still playing out,” Gernon said in a statement. “The legacy of continental breakup on other parts of the Earth system may well be far more pervasive and long-lived than we previously realised.”

Junlin Hua, a seismologist and professor at the University of Science and Technology of China, said he believes the mechanism in the study to explain the anomalies is novel and could be applied to other regions where rifting occurs. Hua was not involved in the study, but he recently authored research that found that the underside of the North American continent is dripping rock blobs.

“The mechanism presented in this study shows a great potential solution for the puzzle, but more relevant observational and modeling works might be needed to further confirm it, and as said in the paper, multiple mechanisms may play a role together,” Hua said. “In any case, personally, this is a great piece of work that opens a new door to improve our understanding of the region.”

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For centuries, people have been searching for ways to reverse the effects of aging. A new study has now revealed that factors present in young human blood can rejuvenate aged skin. 

As we age, the cells and tissues lose their ability to function properly, making us more susceptible to disease and, ultimately, death.

Scientists have been working to understand what drives aging and how to maintain health in old age. They suggest that the secret to youth may not lie in anti-aging products, but rather in our blood. 

Young blood and skin aging

Skin, our largest organ, shows the earliest and most obvious signs of advancing age. This makes it an ideal tissue for studying the mechanisms and effects of aging.

To date, only a handful of approaches have shown promise in reversing the signs of aging. One such approach is a unique method known as heterochronic parabiosis. 

In this approach, the researchers connected the blood circulation systems of two animals of different ages.

When the bloodstream of an old mouse was connected to that of a younger one, the tissue function and cellular activity of the old mouse improved. 

In another experiment, scientists intravenously injected exosomes, which are small extracellular vesicles, from the blood plasma of piglets into old rats. Surprisingly, the rats’ hearts, livers, and blood showed significantly fewer signs of aging.

Can human aging be reversed?

When we age, our DNA undergoes epigenetic changes, which are considered a key hallmark of aging. These reversible changes can now be tracked using DNA methylation-based clocks, also known as epigenetic age clocks. 

These are biological markers that estimate age based on specific DNA-methylation patterns. Since these models are trained on DNA from individuals of all ages and tissue types, they can predict biological age from unknown samples. 

In a recent clinical trial, older adult participants received an intramuscular injection of umbilical cord plasma concentrate.

Blood samples taken afterwards revealed a drop in biological age, suggesting that age reversal might also be possible in humans.

But what about the skin? Scientists still need to determine whether these rejuvenating effects extend to other organs, particularly the skin.

Moreover, the exact mechanisms behind these age-defying effects remain poorly understood. This is where MPS (microphysiological systems) comes into play.

Simulating aging skin in the lab

Scientists developed organ-on-a-chip platforms, or MPS, to study human biological processes. These are advanced models, created in the lab, that simulate human organs.

They consist of organoids made of multiple cell types, integrated with a fluid-flowing system that mimics blood circulation.

The first engineered MPS recreated parabiosis in the muscle of mice and rats tissue. However, translating these experiments to human cells has proven more challenging.

In the new study, scientists used MPS to model how juvenile blood affects aging human skin. Importantly, they also incorporated a bone marrow (BM) organoid, a model of the soft tissue found inside bones.

Bone marrow harbors a mix of stem cells, including hematopoietic stem cells (HSCs), mesenchymal stem cells (MSCs), and others destined for a variety of roles.

HSCs are the body’s blood factories, producing blood cells throughout life. These cells respond to signals in the blood by secreting different molecules, such as cytokines, growth factors, and chemokines. 

These signaling molecules play critical roles in making new blood cells, fighting infections, and healing damaged tissues.

HSCs and all other BM-derived immune cells do not just stay put. They travel to both wounded and non-wounded skin, supporting regeneration and repair.

Young blood revives bone marrow

Over time, our bone marrow loses efficiency and regenerative capacity. The self-renewal capacity of HSCs declines, immune response weakens, inflammation builds up, and epigenetic changes accumulate. 

To test this, scientists created a BM model within the MPS and paired it with a full-thickness skin model. They then introduced it to the serum from young and old human donors.

The results were remarkable. Young serum reprogrammed the marrow cells and restored youthful appearance and function to the skin.

Cytokines and immune cells in the blood are likely involved in mediating these effects. Skin rejuvenation is not just a local event, but is influenced by signals from other organs. 

As bone marrow ages, it releases inflammatory cytokines, weakening the immune response and disrupting repair.

This finding underscores the importance of bone marrow-skin communication and demonstrates the value of MPS platforms in studying systemic rejuvenation in human models.

Bone marrow and skin work together

But here is the twist. These effects were only observed when both the skin and BM organoids were connected in the same system. 

The finding suggests that the bone marrow does not act alone. It secretes rejuvenating factors in response to blood signals, helping reverse the signs of skin aging. 

Specifically, the scientists identified 55 age-associated proteins produced by the BM model when exposed to young blood. Several of these proteins directly improved aging skin in laboratory tests. 

Toward targeted age-reversal therapies

This study is the first proof that young blood can restore youthful skin in a lab-grown system. The effects depend on the communication between the skin cells and the bone marrow. 

Seven of the identified proteins stand out as possible key players to reverse aging.. These findings could open the door to targeted therapies to reverse aging in skin.

But more importantly, they reveal that our skin’s age is not just written in its cells. It is shaped by signals from our blood and, even more, from the bone marrow that creates it.

The full study was published in the journal Aging-US.

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Nature has lots of ways of producing similar-looking things. In this case, ancient water and wind produced a feature on Mars that looks strikingly like coral. Whereas the coral found in Earth’s oceans is built up from the secretions of tiny sea creatures, this rock (imaged on July 24 by NASA’s Curiosity rover) was formed by billions of years of erosion by wind and dust. Image credit: NASA et al.

Lunar Trailblazer’s mission is officially over. NASA’s mission to map water on the Moon launched on Feb. 26, but mission operators lost contact with the spacecraft shortly afterwards. On July 31, NASA declared an end to the extensive efforts to re-establish communications with the orbiter.

Firefly is heading back to the Moon. NASA announced last week that it has awarded Firefly Aerospace $176.7 million to deliver two rovers and three scientific instruments to the lunar surface as part of the Commercial Lunar Payload Services program. Firefly’s contribution will fly on missions slated to land on the Moon in 2026 and 2028.

Life on other worlds could be fueled by cosmic rays. When these energetic particles coming from beyond the Solar System hit water ice, they can smash water molecules apart and release electrons. New research suggests that this process could create an energy source for life in cold, icy worlds like Europa, Enceladus, and parts of Mars.

A new Congressional caucus has formed to support human space exploration. The Advancing Humanity in Space Congressional Caucus, established with the support of Space for Humanity, aims to address the challenges, opportunities, and support needed for spaceflight, space exploration, and human expansion into space.

Scientists have captured a remarkable glimpse into the high-speed lives of red-footed boobies. These seabirds, native to the Indian Ocean’s remote Chagos Archipelago, have been filmed mid-flight, catching flying fish.

The footage confirms a long-held suspicion: these birds can snatch fish directly from the air.

Researchers fitted two boobies with lightweight cameras. Of 15 prey capture attempts, 14 were aerial pursuits. Only one was a dive.

“The cameras recorded footage of the birds catching flying fish just above the surface of the water, while on the wing,” said Dr. Ruth Dunn, the study’s lead author from Heriot-Watt University.

“We suspected this happened, but this is the first time we’ve had bird-borne footage showing them foraging and catching fish mid-air. It could suggest they are catching a significant portion of their diet in this way.”

Optimal winds for catching fish

The study combined GPS and accelerometer trackers on 18 additional birds. The researchers tracked 45 foraging trips in total. The birds typically traveled hundreds of kilometers during each outing. These trips showed clear wind preferences.

Red-footed boobies are flap-gliding seabirds. They alternate between flapping and gliding flight. This style makes them efficient in tailwinds and crosswinds but not headwinds.

When heading out from the colony, they strongly preferred crosswinds or tailwinds. On their way back, they still used crosswinds but showed more flexibility.

The birds did not rely on familiar feeding spots. Their prey – mostly flying fish – is patchily distributed and unpredictable. Selecting optimal winds helps reduce energy costs during these long journeys.

Riding the wind to save energy

The analysis revealed a strong link between wind direction, speed, and flight behavior. Boobies flapped more when flying into headwinds.

The birds flapped less in crosswinds, and even less in tailwinds. These choices helped them maintain higher speeds while spending less energy.

The average ground speed reached about 22 miles per hour. When birds flew with crosswinds at high wind speeds, they moved fastest and glided more. In contrast, headwinds forced them to flap harder and slowed them down.

Seabird behavior linked to wind

Red-footed boobies were more likely to feed in windy conditions. Their feeding behavior – especially capturing flying fish – appeared closely linked to wind.

Flying fish can glide farther and stay aloft longer when supported by strong winds. This increases their exposure and gives boobies a better chance of catching them.

In fact, human fishers also report better catch rates for flying fish during high winds and larger swells. These conditions improve flying fish habitats through nutrient-rich upwellings.

The role of wave direction

Waves also played a role. Though wind and wave height were often linked, birds reacted differently depending on wave direction.

When waves aligned with the birds’ movement, feeding became more likely. The interaction between wind and wave direction likely affects both the birds and their prey.

Boobies have relatively low aspect-ratio wings. This gives them better turning agility, an advantage when chasing flying fish. In windy seas, such agility becomes even more important.

Outbound trips are less fixed. Boobies can experiment with wind choices while seeking prey. But inbound journeys are more direct. Even so, birds often chose crosswinds to return faster.

Seabirds in a changing world

As climate change alters global wind patterns, seabird behavior will likely shift. Some models predict stronger storms and higher wind speeds.

Others suggest long-term global stilling. Either way, red-footed boobies may benefit from increased winds on the ocean – at least up to a point.

“Gaining a clearer understanding of such environmental effects will enable us to predict how they will cope in the future,” said Professor Stephen Votier.

Extreme conditions such as cyclones may test these birds’ limits. Yet boobies seem more resilient to storms than many tropical seabirds. Their ability to catch aerial prey in strong winds gives them a potential edge.

Feeding zones need protection

This study links wind with both flight efficiency and feeding success, and shows how red-footed boobies use nature’s forces to boost survival.

With wind as both ally and obstacle, their future will depend on how the climate continues to shift.

Marine conservation should consider not just breeding islands but also wind-affected feeding zones. Protecting these dynamic habitats will be key to the long-term survival of this flying fish specialist.

The study is published in the journal Proceedings of the Royal Society B Biological Sciences.

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A recently published series of scientific papers is calling for action to strengthen research and harmonize methodologies for the measurement and assessment of tire wear emissions.

The State of Knowledge: Tire Wear Emissions During the Use Phase series reviews over 850 peer-reviewed scientific publications from the past 40 years and states that it sees existing research on tire wear emissions as scattered, inconsistent and inconclusive.

Supported by the Tire Industry Project (TIP), the series consists of three distinct papers, each addressing a critical layer of tire wear emission knowledge. The first two published papers focus on the characterization of tire wear emissions and the assessment of their environmental impact. The third paper, expected to be published in late 2025, will focus on potential health impacts.

Dr Stephan Wagner, a guiding force behind the papers, explained, “The topic of tire wear emissions is extremely complex, multi-dimensional, and unfortunately only partially understood. While notable progress has been made over the years in analyzing such emissions, significant knowledge gaps and inconsistencies prevent a full understanding of their behavior and impact.

“Until these gaps are closed, there is a growing concern that decisions about tire emissions could be based on incomplete science. Resolving this requires all stakeholders — academia, industry and policymakers — to collaborate and drive for consistency, built on shared research and assessment models such as those proposed in our papers.”

Larisa Kryachkova, executive director at the Tire Industry Project, remarked, “Ever since our inception 20 years ago, our mission has been to strengthen scientific foundations to drive industry action. The SOK underscores why we need a concerted, multi-stakeholder response to close the knowledge gaps, now more than ever. It also reinforces our ambition to build a more open, collaborative research ecosystem, through initiatives such as the Open Call for Projects and the upcoming Tire Emissions Research Conference at MIT in Boston.”

Paper 1: Tire emissions during the use phase of tires — current and future trends 

The paper stresses the importance of characterizing tire wear emissions by identifying what is released, how it is released and where it ends up. Emissions are defined as including particulates, volatiles and dissolved compounds, with particulate tire wear appearing as tire and road wear particles (TRWP) made up of tire tread, road pavement, brake systems and mineral dust.

In comparison, volatiles may come directly from the tire or from released particles, while dissolved compounds can occur from the tire itself on wet roads or through abraded wear. To assist risk characterization of tire emissions, the paper proposes a conceptual exposure model (CEM) that outlines emission mechanisms, affected environments, potential exposure and pathways through which this exposure may occur.

Factors influencing emissions, including driving style and road conditions, have also been considered. The paper calls for a tiered TRWP measurement framework and standardized protocols to enable reliable comparisons and informed decisions.

Paper 2: Risk assessment of tire wear in the environment — a literature review

This paper assesses whether current knowledge supports robust environmental risk assessment and concludes that data is insufficient, particularly on tire leachables and volatiles, due to inconsistent hazard information.

It notes that varying testing methods hinder comparisons and definitive conclusions, underscoring the need for harmonized guidelines. While there’s no standard method for assessing tire wear emissions, existing frameworks for microplastics are considered a starting point, with some adjustments to fit the unique nature of tire wear emissions.

A tiered hazard assessment has been proposed, beginning with tests on cryogenically milled tire tread (CMTT) and advancing to realistic conditions. The paper calls for collaboration among industry, policymakers and academia to develop standardized approaches for sampling, analysis and hazard evaluation.

“We are pleased with how the SOK project has evolved and the role it can play in ensuring a collective understanding of tire wear emissions, cutting through the misinformation. It has been an intense team effort for the past two years, and we appreciate how TIP supported this project, while maintaining our independence and autonomy. We hope that these papers will encourage the scientific community and serve as a catalyst for further research and standardization,” said Wagner.

To ensure an unbiased perspective, both papers were elaborated on and discussed with external scientists including TIP’s Assurance Group members Dr J Spengler from Harvard University and Dr How Yong from Beijing Normal University, as well as with the advisory panel expert Dr T Mincer from Florida Atlantic University.

In related news, two days of development testing for Pirelli’s 2026 tires were carried out at the Hungaroring on August 5 and 6, with support from McLaren and Racing Bulls on day one and Alpine and Scuderia Ferrari the following day. Read the full story

Those Who Don’t Know

The evening before Fuchs and I had lunch, he had given the first official physics talk of the conference, a lightning review of QBism and a report on some conjectures in number theory that QBist thinking had helped him make recent progress on. His closing words at the end of the question-and-answer session following the talk were, “QBism is here to stay. You won’t get rid of me.”

Then Gisin took the stage to discuss the nature of measurement and started his talk with an improvised dig at the QBist perspective. “Physics is all about extracting information about how nature does it. Nature,” Gisin said, pausing for emphasis and looking slowly out over the audience, “not agents.” The audience tittered. (Fuchs later told me they had carried their friendly sparring about the finer points of QBism to the local watering hole that night.)

I caught up with Gisin the next evening for dinner. Or at least that was the plan, but I joined him and his graduate students a few minutes after 6 p.m. The restaurant’s kitchen had just closed. He stood up for me, exchanging sharp words with the server. It was not the only testy encounter I witnessed between punctual islanders and the looser, often hungry physicists. “The island is stuck in the 1960s, as opposed to the rest of Germany, which has at least made it to the 1970s,” Burgarth, a native German, complained. “It’s cash only, no English, has crap food, and everything closes at 6. Although everyone is very nice.”

Gisin was kind enough to share with me both his seafood bouillabaisse and his vision for how to demystify measurement. He pointed out that the quantum state used in the Bell test — the white lab rat of quantum physics — is an exceedingly unusual state. Taken individually, Alice’s measurements and Bob’s measurements both appear completely patternless. Half the time, Alice measures one outcome, and half the time she measures a different outcome. It’s only when the two bring the lists together that they see Bell’s mysterious pattern of correlations emerge. There is information in pairs of particles, but not in individual ones.

But almost any other state will be different. Imagine a state where Alice gets one outcome 70% of the time and another outcome 30% of the time. She will see a pattern in her data. And she may discern a second pattern when she compares notes with Bob. In this case, their particles carry both “local” information — the pattern that Alice and Bob can discern on their own — and the “nonlocal” information that emerges only when they compare notes. When particles share both local and nonlocal information, how to measure them and extract that information is not so clear.

Gisin hopes that by fooling around with measurements of these more exotic states, physicists will come to better understand the role of measurement in general. He doesn’t know what the conventional wisdom will become when that happens, but he hopes that measurements will be seen to have one unique outcome (ruling out many-worlds), and that the world out there exists and can be described by rules that don’t depend on the actions of agents (ruling out QBism).

Helgoland’s anti-Fuchs was Gemma De les Coves, a soft-spoken physicist from Barcelona. “I do not understand quantum mechanics,” she declared. “I don’t know if the quantum state is a description of reality or a way to place bets. I would love to know if there are many worlds, and if I am splitting into many Gemmas as I speak.”

De les Coves began her career in physics studying the ways that information behaves in quantum systems. But she eventually grew dissatisfied with the clashing instructions for how the quantum state evolves: according to the Schrödinger equation at some times and by collapse at others. “You cannot swallow them,” she told me the next day. “They are a bunch of mathematical recipes, and they are inconsistent.”

Over the last few years, she has contributed to a research program that aspires to coax the quantum omelet to unscramble itself by infusing it with increasing doses of realism.

Last year, De les Coves and her collaborators studied a simple theory of a classical universe — one populated with objects in definite states, such as particles that are each in a specific spot. Then they put an agent in the theoretical universe and calculated how much the agent could learn about the particles according to classical physical laws. Surprisingly, they found that the agent couldn’t learn everything. As a necessary consequence of being trapped inside the universe, the agent would perceive certain particles as having a quantumlike state with multiple possible positions, even though from the God-like view outside the universe the particles do have real, specific positions. It’s only a simple model, but if our universe works the same way, then the simultaneous possibilities of ψ could be an artifact of our also being trapped inside our universe.

De les Coves’ work complements years of research from Robert Spekkens, a physicist at the Perimeter Institute. He has shown that in any world where agents are ignorant of details like exact particle positions (even if those positions do exist in a fixed, classical sense), that ignorance leads to a laundry list of allegedly quantum phenomena, such as the “teleportation” of a quantum state from one particle onto another. “If you have a classical model where you cannot know some things,” De les Coves said, “surprisingly, you can reproduce many things that appeared quantum.”

I chased down Spekkens as we were leaving the lecture hall on another afternoon. Since he’s been able to derive quantumlike effects from largely classical theories, does he think that reality might turn out to be classical after all, I asked — that Bell particles might have real, fixed properties before they get to Alice and Bob? He told me that someday he suspects physicists will look back at questions like that and realize they don’t make much sense, because a new way of thinking about reality will have subsumed both classical and quantum physics.

He brought up the omelet again and said that he’s been picking away at the knowledge side of it, deriving exactly how much of the canon of quantum weirdness can be chalked up to our ignorance. He’s found that quite a bit of ψ’s quantum strangeness — perhaps more than most people realize — can be explained if we assume it represents information as opposed to a physical entity. But it can’t all be explained that way. The remaining piece — the part we might call reality — he suspects will be largely about how one thing influences another.

“I think the essence of reality is causal connections,” Spekkens said.

As a loose metaphor, he suggested I picture a sort of black-and-white mosaic. I imagined one that portrayed a northern gannet of the sort I’d seen nesting on the cliffs during a walk around the Helgoland plateau. Based on our classical experience, we are accustomed to knowing the specific color of every tile. Perhaps, Spekkens suggested, that’s not essential. After all, if you flip every tile to the opposite color, you’ll still see the gannet’s silhouette. It’s the relationships between the tiles that matter, not their definite state.

Similarly, if physicists can fit both quantum and classical physics under some shared umbrella of realism, the specific states of the particles themselves might be meaningless compared to the way they can influence each other. “Maybe that’s sufficient to have a notion of reality,” he said, but “that’s the part where I know the least about how things are going to work out.”

Gravity to the Rescue?

Buffeted by dozens of competing accounts, I often felt as if we were little closer to understanding the nature of reality in 2025 than Heisenberg was in 1925. Some researchers also felt that a certain ennui has settled over the effort to interpret quantum mechanics. “What do we do when we’ve been working on a problem like this with some very great minds for the last hundred years?” asked Elise Crull, a philosopher and historian of physics at the City College of New York.

The Exploration Company has completed a hot fire test campaign for the thrust chamber of its Huracan rocket engine. The testing put the fourth prototype of the thrust chamber through its paces, including introducing deliberate pressure disturbances to assess its performance under stress.

Developed to power The Exploration Company’s Nyx Moon spacecraft, the Huracan engine will support missions to both lunar orbit and the Moon’s surface. While the company has not recently updated progress on its Nyx Moon spacecraft, a late-2024 presentation projected completing an inaugural mission to the Moon’s surface in 2029. The presentation also revealed that the service would offer capacity for commercial payloads at a cost of around $200,000 per kilogram.

On 7 August, the company announced that it had completed a series of 11 hot fire tests of the fourth iteration of the Huracan engine’s thrust chamber. A thrust chamber is the part of a rocket engine where fuel and oxidiser mix and combust, producing hot gases that are then expelled through a nozzle to generate thrust. This version of the Huracan’s thrust chamber employs a lighter and simpler chamber architecture that reduces overall production time.

The test campaign was conducted at the Airborne Engineering testing facilities in Westcott, England. According to the company’s 7 August update, the testing, which involved imposing deliberate pressure disturbances, validated the thrust chamber’s high-frequency combustion stability, ensuring that it can manage rapid pressure oscillations that can occur during combustion without compromising performance or structural integrity.
In addition to the thrust chamber itself, testing was also focused on the company’s newly developed GOX/GCH4 ignitor. According to the company, the ignitor performed as expected with “zero missed starts.”

While the company prepares for missions to the Moon, its near-term goal is closer to home. It is preparing for the inaugural flight of Nyx Earth, which will transport cargo to and from low Earth orbit. On the road to that first flight, the company plans to launch a third subscale prototype after its Mission Possible demonstrator failed moments before parachute deployment earlier this year. The company has not yet shared when it expects to launch this third demonstration mission.

Don’t let the brilliant Moon deter you from enjoying the best meteor shower of the year: the 2025 Perseids.

It’s that time of year once again. August sees warm nights, with late summer campers out awaiting that ‘Old Faithful’ of annual meteor showers: the August Perseids. While 2025 also sees the shower peaking right around Full Moon, don’t despair; with a little bit of planning and patience, you can still catch this shower at its best.

Perseid Prospects for 2025

The radiant rises to the northeast around local midnight. The peak for 2025 is expected to occur right around August 12th at 3:00 Universal Time (UT), favoring northern Europe at sunrise. North America rotates into the stream about 4-6 hours later.

Expect rates topping 50-100 per hour to pick up towards local sunrise, as your viewing site turns into the stream. Think of a car (the Earth) speeding down the highway; the forward windshield gets the bugs (the meteors). You’ll know if you saw a Perseid, if you can trace the path of the meteor back to the shower’s radiant point along the Perseus-Cassiopeia border.

Be sure to check out the planetary parade on meteor dawn patrol, with Mercury low to the east, Saturn high to the south, and a very close together Jupiter and Venus on the morning of the 12th.

The source of the shower is periodic comet 109P/Swift-Tuttle. Discovered by astronomers Lewis Swift and Horace Tuttle in July 1862, records of apparitions for the comet go all the way back to Chinese observations in 322 BC. The comet was notable as the first linked to an annual meteor shower.

A sketch of Comet Swift-Tuttle by astronomer G.J. Chambers on the night of August 23rd. Credit: Public Domain.

On a 133 year orbit, Comet Swift-Tuttle last reached perihelion on December 12th, 1992, when rates for the Perseids picked up. Swift-Tuttle won’t visit the inner solar system again until 2126.

The orbital path of Comet Swift/Tuttle. Credit: NASA/JPL/Horizons.

Now, for the bad news: the (-90%) illuminated, waning gibbous Moon sits nearby in Pisces around the 12th, just 3 days after Full on August 9th. This will cut down on the number of faint meteors, though I wouldn’t let it deter you in your meteor shower quest.

The Perseid radiant looking to the east versus the Full Moon on the night of August 12th. Credit: Stellarium.

The Perseids are often referred to as the ‘Tears of Saint Lawrence,’ after the saint of the same name, who was martyred on August 10th, 258 AD. There’s evidence that the name is a modern construction. The earliest written reference to the saint’s association with the meteor shower seems to only go back to Edward Herrick in 1839. I’ve found that the reference is well-known in rural southern Spain.

Observing the 2025 Perseids

Meteor shower watching is actually pretty low tech. All you really need to enjoy the Perseids is a sturdy lawn chair, a hot beverage, and patience. A friend can help scan the sky, as Perseids can appear in any direction from the radiant. You can beat the Moon by selecting your observing site beforehand to place its glare behind a nearby hill or building.

A Perseid meteor seen over Oxfordshire, UK in 2022. Credit: Mary McIntyre.

The Perseids often produce a twin peak spaced a few hours apart worldwide, so it’s always worth watching on nights leading up to and after the expected maximum. The Perseids are also a prodigious producer of fireballs, which can briefly light up the scene with surprising brilliance, leaving a persistent smoke train. I once saw a Perseid while watching from northern Maine that had an audible hiss. We now know that you can ‘hear’ meteors via a localized phenomenon known as ‘electrophonic sound’. Tune an FM radio to an unused frequency, and you may just hear meteor ‘pings’ amoung the static.

A Perseid meteor pierces the scene, during a northern lights display on the night of August 12th, 2024. Imaged from Assateague Island National Seashore, Maryland. Credit: Jeff Berkes. (instagram/flickr)

Clouded out? You can still catch the Perseids live on August 12th starting at 21:00UT/5:00PM EDT, courtesy of Astronomer Gianluca Masi and the Virtual Telescope Project.

A Perseid meteor imaged from the International Space Station. Credit: NASA

Don’t miss the August Perseids, as one of the best meteor showers for 2025.

Lead image credit: Boris Štomar

Thanks to the Hubble Space Telescope, we now have the sharpest image yet of the interstellar visitor 3I/ATLAS, showing that it is clearly a comet, with a coma filled with dust particles and the first hints of a tail.

Of course, 3I/ATLAS is no ordinary comet. Discovered on July 1, 2025 by the Asteroid Terrestrial-impact Last Alert System (ATLAS), 3I/ATLAS is the fastest comet ever seen. Racing in-system at 130,000 mph (209,000 kph), it is hurtling through space so fast that it will escape the sun’s gravitational grasp. Its origin is somewhere beyond the solar system, in interstellar space where it has traveled for aeons, being sped up by gravitational slingshots every time it encounters a star. As a result, 3I/ATLAS is just passing through, and will gain another slingshot from our sun to send it on its way back into interstellar space, never to be seen again.