Category: 7. Science

Scientists have long used sound to study wildlife. Bird calls, bat echolocation and whale songs, for example, have provided valuable insights for decades. But listening to entire ecosystems is a much newer frontier.

Listening to rivers is especially tricky. Beneath the water is a soundscape of clicks, pops and hums that most of us never hear. Many of these sounds are a mystery. What produces them – an insect? A fish? The water itself?

A new tool developed by my colleagues and I aims to help scientists decode what underwater river sounds really mean. We hope it will help monitor river health and tell the untold stories of these fascinating underwater places.

Sonic sleuthing

Rivers around the world face growing threats, including pollution, water extraction and climate change. So scientists are always looking for better ways to keep an eye on river health.

Sometimes river animals make sounds to attract a mate or ward off rivals. Other times the noise may simply be incidental, made when the animal moves or feeds.

These sounds can reveal a lot. Changes in the pattern or abundance of a sound can be a sign that a species is in decline or the ecosystem is under stress. They might reveal that a species we thought was silent actually makes sounds. Or we might discover a whole new species!

That’s why scientists use sound to monitor ecosystems. It essentially involves lowering waterproof microphones into the water and recording what’s picked up.

Recorders can run continuously, day and night, without disturbing wildlife. Unlike cameras, the recorders work in murky waters. And scientists can leave a recorder running and leave, allowing them to capture far more information with far less effort than traditional surveys.

Every recording is a time capsule. And as new technology develops, these sound files can be re-analysed, offering fresh insights into the state of our rivers.

But there’s a catch. Analysing the hours of recordings can be very time-consuming. Unlike for land-based recordings, no automatic tools have existed to help scientists identify or document what they’ve recorded underwater.

The best method available has been painfully old-fashioned: listening to recordings in real time. But a single recorder can capture tens of thousands of sounds each day. Manually analysing them can take a trained professional up to four times longer than the recording itself.

Our new, publicly available tool sought to address that problem.

A smarter way to listen to rivers

Our tool uses R, a free program for analysing data. The author of this article wrote a code instructing the program to analyse sound from underwater recordings.

We then uploaded sound recordings from Warrill Creek in Southeast Queensland. The program scanned the recordings and pulled out each individual sound.

Using the frequency, loudness and duration of every sound, it compared them all — a mammoth task if done by hand. Finally, it grouped similar sounds together — for example, clicks with clicks or hums with hums — turning them into simple clusters of data.

This process allows researchers to study the sounds more easily. Instead of spending hours listening to a recording and trying to distinguish the clicks of waterbugs from the grunts of a fish, the tool sorts the sounds into groups so researchers can jump straight to analysing patterns in the data.

For example, they might analyse which sounds are present in which rivers, or how the sounds change over time or between regions.

In yet-to-be published research, we tested the tool on a further 22 streams and found it successfully processed the sound data into groupings.

Our study found the tool is accurate. It correctly identified almost 90% of distinct sounds – faster and with far less effort than manual listening.

Listen to life beneath the surface

Listen to this recording of waterbugs from the order Hempitera. You’ll hear a chorus of sharp clicks, like marbles rattling in a glass. The recording is filled with hundreds of near-identical calls — a task that would take hours to label by hand.

After we uploaded the sound file, the tool grouped these repetitive calls automatically, saving huge amounts of listening time.

Below is an underwater recording of aquatic macroinvertebrates. The calls of these tiny river creatures, from the orders Hemiptera and Coleoptera, hum like cicadas. The sound is interspersed with the grunts of a fish (order Terapontidae), all set against the quiet backdrop of flowing water.

The tool can handle these layers, grouping sounds to show the community beneath the surface.

In this next clip, the sound of flowing water is prominent. This is one of the biggest challenges in listening to rivers. But our tool can separate out sounds masked by the constant background noise, so scientists can analyse them.

Below, a chorus of clicking macroinvertebrates fills the recording, until a vehicle sound cuts across from above the water’s surface. It shows how easily human noise crosses the boundary between air and water.

Helping protect our rivers

The tool allows underwater recordings to be processed at scale. It moves beyond hours of manual listening towards truly exploring what rivers are telling us.

It’s also flexible, able to handle data sets of any size, and adaptable to different ecosystems.

We hope the tool will help protect rivers and other water resources, such as oceans. It opens up new ways to monitor these environments and find strategies to protect them.

Scientists have only just begun exploring freshwater sound. By making this tool free, easy to use and publicly available, we hope more people can join in, ask questions and make discoveries of their own.

Gloabl team expands gravitational wave catalogue with 128 new detections

by Sophie Jenkins

London, UK (SPX) Sep 03, 2025

An international network of gravitational wave observatories has more than doubled the number of known cosmic collisions, detecting 128 new mergers of black holes and neutron stars. The results, published in the updated Gravitational Wave Transient Catalog (GWTC-4.0), showcase the expanding reach of the LIGO-Virgo-KAGRA collaboration.

The detections, gathered between May 2023 and January 2024, mark a turning point in gravitational-wave astronomy. Improved sensitivity in the detectors, now 25 percent greater than before, enabled scientists to probe deeper into the cosmos and uncover signals from massive and distant systems.

Among the discoveries is GW230814, the loudest gravitational wave recorded to date, which hints at black holes formed from previous mergers. The catalogue also includes evidence of two black hole-neutron star collisions, broadening the variety of cosmic events studied.

UK researchers have played a central role in both instrumentation and data analysis, supported by the Science and Technology Facilities Council. Teams from the University of Glasgow, the University of Portsmouth, and Royal Holloway contributed significantly to the detectors’ precision and to extracting faint signals buried in noise.

Dr Daniel Williams from the University of Glasgow noted that the new results highlight the strength of the international network and the analytical tools developed to interpret complex data.

The expanded catalogue enables more precise tests of Einstein’s general relativity and refines measurements of the Universe’s expansion rate, including the contested Hubble constant. Tessa Baker of the University of Portsmouth emphasized the excitement of releasing over a hundred new events, providing vital cosmological insights while affirming the consistency of gravity on large scales with Einstein’s theory.

Looking ahead, researchers expect even more breakthroughs as future facilities, such as the Vera Rubin Observatory, link gravitational wave detections with light-based observations. This multi-messenger approach promises to unravel deeper mysteries about stars, black holes, and the forces shaping the Universe.

Research Report:GWTC-4.0: Updating the Gravitational-Wave Transient Catalog with Observations from the First Part of the Fourth LIGO-Virgo-KAGRA Observing Run

Related Links

LIGO

The Physics of Time and Space

Another SpaceX Falcon 9 rocket just earned its wings.

A Falcon 9 with a brand-new first stage lifted off from Vandenberg Space Force Base in California today (Sept. 2) at 11:51 p.m. EDT (8:51 p.m. local time; 0351 GMT on Sept. 3), carrying 24 of the company’s Starlink internet satellites toward low Earth orbit (LEO).

Enhanced CHARA Array to Gain Full Spectrum Observing Power with NSF Grant

by Clarence Oxford

Los Angeles CA (SPX) Sep 03, 2025

A $1.39 million award from the National Science Foundation will significantly upgrade Georgia State University’s Center for High Angular Resolution Astronomy (CHARA) Array, enabling observations across the entire visible and near-infrared spectrum.

Funded through the NSF’s Major Research Instrumentation Program, the project will deliver advanced optics, new controllers, and a high-sensitivity tracking detector. These improvements will allow astronomers to simultaneously capture light at multiple wavelengths, offering sharper insights into stars, stellar nurseries, and galaxies.

“It’s incredibly rewarding to see what’s possible when curiosity meets cutting-edge technology,” said Array Director Gail Schaefer. “We are committed to delivering a world-class experience for astronomers exploring the cosmos and this upgrade gives our scientists a powerful new way to image stars in different wavelengths at the same time.”

Located on Mount Wilson in California, the CHARA Array consists of six telescopes that combine their light through interferometry, creating one of the world’s most powerful tools for detailed stellar imaging. Operated by Georgia State, the array functions as a precision cosmic zoom lens, producing images with extraordinary clarity.

The new instrumentation, expected to be operational in 2028, will resolve long-standing limitations. “With this new NSF award, we will soon have the means to use [the CHARA cameras] simultaneously across the color spectrum,” said Doug Gies, Regents’ Professor of Physics and Astronomy and director of CHARA. “With these new capabilities, CHARA will be able to explore the universe with unprecedented clarity, inspiring new discoveries and a new generation of astronomers.”

Georgia State Provost Nicolle Parsons-Pollard praised the achievement, calling it a milestone for the university’s astronomy program. “The enhanced ability to observe stars across the full spectrum of visible and near-infrared light marks a remarkable advancement, firmly positioning Georgia State at the forefront of astronomical research,” she said.

Related Links

Georgia State University

Stellar Chemistry, The Universe And All Within It

New study links satellite discharges to electron buildup in orbit

by Clarence Oxford

Los Alamos NM (SPX) Sep 03, 2025

For the first time, researchers have established a direct correlation between the frequency of spacecraft electrical discharges and the number of electrons in the surrounding space environment. The findings could inform future methods of protecting satellites from potentially damaging effects.

Spacecraft environment discharges (SEDs) are short-lived electrical breakdowns that can harm sensitive electronics and disrupt communications. They result when electrons accumulate on spacecraft surfaces, creating uneven charging. When the voltage reaches a critical threshold, the stored energy is suddenly released – similar to a static shock on Earth.

“We’ve long known that these SEDs exist,” said Amitabh Nag, a scientist at Los Alamos National Laboratory and lead author of the study. “But we haven’t understood the relationship between the electrons in the space environment and SEDs. To do that, we needed two sensors on a single spacecraft: one that looked at the number and activity of electrons, and another that looked at the radio frequency signal.”

The Department of Defense’s STP-Sat6 satellite in geostationary orbit carries both instruments, developed at Los Alamos. This unique configuration enabled researchers to analyze electron activity alongside radio frequency discharge data collected over more than a year.

The team identified more than 270 periods of high-rate discharges and several hundred episodes of elevated electron flux. In about 75 percent of cases, surges in electron activity preceded SED events by 24 to 45 minutes. This suggests low-energy electrons in the 7.9 to 12.2 keV range play a critical role in priming spacecraft surfaces for discharges.

“We observed that as electron activity increases, especially in that 7.9 to 12.2 keV range, the spacecraft starts to accumulate charge. This continues until a tipping point is reached and SEDs occur,” Nag said. “That lead time opens the door for potential forecasting tools to mitigate risks.”

According to the researchers, integrating real-time monitoring of low-energy electrons into future missions could provide operators with early warning of impending charging events, allowing preventive measures to safeguard spacecraft systems.

Research Report:Radio Frequency Transients Correlated with Electron Flux Measured On-Board the STP-Sat6.

Related Links

Los Alamos National Lab

Space Technology News – Applications and Research

Magnetic fields in the young universe revealed as incredibly faint

by Erica Marchand

Paris, France (SPX) Sep 03, 2025

The first magnetic fields that emerged after the Universe’s birth may have been billions of times weaker than the pull of a refrigerator magnet, with intensities comparable to the magnetism created by neurons in the brain. Despite their weakness, researchers have found that these fields left detectable traces in the cosmic web that spans the Universe.

The conclusions come from a collaboration led by SISSA (International School for Advanced Studies, Trieste), working with teams from Hertfordshire, Cambridge, Nottingham, Stanford, and Potsdam. The scientists ran roughly 250,000 computer simulations to explore the behavior of primordial magnetic fields, validating the results with astronomical observations. The findings, published in Physical Review Letters, define the possible and maximum strengths of these early fields and offer insights into how the first galaxies and stars arose.

“The cosmic web, of which much remains to be discovered, is a filamentary structure connecting galaxies across the Universe,” explained lead author Mak Pavicevic, a SISSA PhD student, with co-author Matteo Viel. “One of its mysteries is why it is magnetised even in the most remote and sparsely populated regions. Our hypothesis was that this could be a legacy of processes in the primordial Universe, either during inflation before the Big Bang or in later cosmic phase transitions.”

By comparing simulations with data, the team demonstrated that models including weak primordial fields better match observations. Pavicevic and Viel note that a Universe with a magnetic field of about 0.2 nanogauss aligns closely with measured data. Co-author Vid Irsic of the University of Hertfordshire emphasized: “These are the most realistic and largest suite of state-of-the-art simulations of the influence of primordial magnetic fields on the intergalactic cosmic web.”

The study establishes a new upper limit on the strength of primordial magnetic fields, significantly lower than prior estimates. This strict constraint is also consistent with independent measurements from the cosmic microwave background. According to the researchers, such magnetic fields would have influenced the density of the cosmic web, speeding up star and galaxy formation. Future observations by the James Webb Space Telescope could provide further confirmation.

Research Report:Constraints on Primordial Magnetic Fields from the Lyman Forest

Related Links

Scuola Internazionale Superiore di Studi Avanzati

Understanding Time and Space

Massive stars in low metal galaxies frequently form binaries

by Clarence Oxford

Amsterdam, Netherlands (SPX) Sep 03, 2025

Astronomers have confirmed that massive stars in galaxies with low metal content often exist in binary systems, much like their counterparts in the Milky Way. An international team of seventy researchers from Belgium, the Netherlands, and Israel used the European Very Large Telescope (VLT) in Chile to monitor massive stars in the Small Magellanic Cloud. Their findings appear in Nature Astronomy.

For two decades, it has been known that many massive stars in the Milky Way are part of binary systems. More recently, astronomers realized that such interactions play a key role in the stars’ evolution. Until now, however, it was unclear whether this was also true for galaxies poor in heavy elements. The new study shows that it is.

“We used the Small Magellanic Cloud as a time machine,” explained Hugues Sana of KU Leuven in Belgium. “Its metallicity is similar to that of distant galaxies when the Universe was only a few billion years old.”

Observing these stars beyond the Milky Way is challenging due to their faint light and great distance. The team relied on the FLAMES spectrograph at the VLT, which can target up to 132 stars simultaneously using fiber optics, making it ideal for such surveys.

Over three months, the astronomers studied 139 O-type stars, each 15 to 60 times the mass of the Sun. These luminous, short-lived stars end as supernovae and collapse into black holes. More than 70 percent of the stars showed telltale acceleration and deceleration in their velocities, indicating the gravitational tug of nearby companions.

“The fact that massive stars in the Small Magellanic Cloud have a partner suggests that the first stars in the universe, which we suspect were also massive, had partners too,” said co-author Julia Bodensteiner of the University of Amsterdam. “Perhaps some of those systems end up as two black holes orbiting each other. It’s an exciting thought.”

The team plans sixteen additional observation rounds to map the stars’ orbits, measure their masses, and characterize their companions. “Using our measurements, cosmologists and astrophysicists studying the young, metal-poor universe will then be able to rely on our knowledge of massive binary stars with greater confidence,” concluded Tomer Shenar of Tel Aviv University.

Research Report:A high fraction of close massive binary stars at low metallicity.

Related Links

Netherlands Research School for Astronomy (NOVA)

Stellar Chemistry, The Universe And All Within It

Voyager 1 was launched 16 days after Voyager 2, but after three months, it overtook it. The main purpose of Voyager 1 was to fly by the outer solar system and later interstellar space, crossing the heliosphere. It reached the Jupiter system in 1979, flew by Amalthea, Europa, Ganymede and Calisto. Next came Saturn, its moons Titan, Tethys, Mimas, Enceladus, Rhea and Hyperion. Where is Voyager 1 now? At this moment, it is 25 billion kilometres from Earth.

Millions of kidney patients could benefit from early detection and prevention as a result of the breakthrough made by scientists at the CRCHUM.

In a groundbreaking achievement, researchers at the CRCHUM, the hospital research center affiliated with Université de Montréal, have identified a type of microRNA that can safeguard small blood vessels and help maintain kidney function following severe injury.

This discovery holds significant promise for the more than four million Canadians living with chronic renal failure, as well as millions of patients worldwide, by offering new possibilities for earlier detection and prevention of the disease.

Until now, there had been no dependable biomarker to assess the condition of these delicate capillaries or to guide targeted strategies aimed at protecting kidney function.

Discovery of miR-423-5p as a biomarker

Findings published in JCI Insight reveal that the microRNA known as miR-423-5p shows strong potential as a blood-based biomarker for evaluating kidney microvascular health.

The study was co-authored by Université de Montréal medical professors Marie-Josée Hébert and Héloïse Cardinal, who hold the Shire Chair in Nephrology, Renal Transplantation and Regeneration, alongside Hébert’s research associate Francis Migneault.

Their research focuses on the decline of peritubular capillaries, a key indicator of chronic renal failure.

These minute vessels, found in the kidneys by the millions, are responsible for removing waste from the blood while delivering oxygen and nutrients essential for kidney function.

Risks and potential applications in patients

Kidney damage that occurs when blood flow is temporarily cut off and then restored can result in the loss of small blood vessels, significantly impairing the organ’s ability to function properly.

“In people who have received a transplant, if kidney function is severely altered, the kidney’s survival is threatened,” said Hébert, a nephrology-transplant physician and UdeM’s outgoing vice-rector for research, discovery, creation, and innovation.

“Using this biomarker, a test could be developed to evaluate the status of the small blood vessels much earlier,” she said. “Doctors in hospitals could then better evaluate the microvascular health of higher-risk patients.

“These could include elderly patients or those undergoing surgeries during which blood flow is temporarily stopped, as is the case for organ transplants or cardiovascular interventions.”

Of mice and… 51 transplant recipients

“We first observed fluctuating levels of miR-423-5p microRNA in the blood of mice with acute kidney injuries,” said Migneault, the study’s first author. “These results were then confirmed in 51 transplant recipients who participated in the CHUM kidney transplant biobank.”

Thanks to this biomarker, clinical teams could confirm whether their interventions improve or diminish the health of small blood vessels.

“But what’s really incredible is that by injecting this microRNA into mice with kidney injuries, we were able to preserve the small blood vessels and limit the damage done to the kidneys,” said Migneault.

While direct injection into the kidney is a clinically feasible method during a transplant, to protect the remaining small blood vessels, the CRCHUM scientists are now focused on alternative techniques to transport the microRNA, or likely a microRNA cocktail, to the kidney.

Potentially useful for other patients

In terms of prevention, a test based on this miR-423-5p microRNA could be useful for patients with cardiac failure, pulmonary failure, or certain neurodegenerative diseases.

“For these medical conditions, the loss of small blood vessels plays a key role, because of the association with normal or accelerated aging,” said Hébert. “Our discovery could, therefore, have a significant impact on the health of all Canadians.”

For those with pulmonary failure, several research projects are in progress under Emmanuelle Brochiero, a researcher and head of the Immunopathology research theme at the CRCHUM.

It may also be possible, using the CHUM’s biological material biobank, to determine if existing medications, administered after a kidney transplant to treat another issue, impact small blood vessel health, added Hébert.

Reference: “Endothelial extracellular vesicle miR-423-5p regulates microvascular homeostasis and renal function after ischemia-reperfusion injury” by Francis Migneault, Hyunyun Kim, Alice Doreille, Shanshan Lan, Alexis Gendron, Marie-Hélène Normand, Annie Karakeussian Rimbaud, Martin Dupont, Isabelle Bourdeau, Éric Bonneil, Julie Turgeon, Sylvie Dussault, Pierre Thibault, Mélanie Dieudé, Éric Boilard, Alain Rivard, Héloïse Cardinal and Marie-Josée Hébert, 22 May 2025, JCI Insight.
DOI: 10.1172/jci.insight.181937

This research was funded by the Canadian Institutes of Health Research, the Shire Chair in Nephrology, Renal Transplantation and Regeneration at Université de Montréal, the Fondation J.-Louis Lévesque, the Canadian Donation and Transplantation Research Program, the Fonds de recherche du Québec—Santé, and the Natural Sciences and Engineering Research Council of Canada. It was supported by the molecular pathology and animal core facility teams.

Dr. Hébert, Dr. Cardinal, Francis Migneault and the members of their team would like to thank the CHUM patients for their participation in the CHUM kidney transplant biobank, as well as the clinical and research staff who ensure the continued existence of the biobank.

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On 7 to 8 September 2025, a chance alignment of Earth, the Moon, and the Sun will see a good swathe of our planet bathed in the eerie red glow of a total lunar eclipse.

It will be the longest total lunar eclipse since 2022, with a totality that lingers around 1 hour and 22 minutes, during which time Earth’s satellite will appear to be dyed a deep, blood-red hue.

To make things even more exciting, the event will be visible from Australia, Asia, Africa, and Europe – which means more than 7 billion people will have a chance to see it, with some 6.2 billion able to observe the totality from beginning to end.

The Americas will mostly miss out, because it will be daytime, but Hawaii, a slice of Alaska, and a slice of Brazil will have a chance to see at least a partial eclipse.

Related: Trailblazing Satellite Mission Delivers Its First Artificial Solar Eclipse

A total lunar eclipse is what happens when Earth passes precisely between the Sun and the Moon in a straight line. As Earth slides in front of the Moon, the planet blocks most of the light from the Sun reaching the surface of the Moon.

Rather than disappearing completely, however, the usually silvery Moon takes on a deep red tinge. This is because only some of the Sun’s rays – the longest wavelengths at the red end of the spectrum – are able to pass through Earth’s atmosphere to reach the Moon beyond, while shorter, bluer wavelengths are scattered by the atmosphere. It’s the same mechanism that turns the sky red at sunset.

From beginning to end, the entire eclipse will last for about five and a half hours, starting at 15:28:25 GMT and ending at 20:55:08 GMT. The totality will commence at 17:30:48 GMT, and finish at 18:52:51 GMT.

There’s a handy tool to convert GMT to your local time here. Alternatively, you can visit Timeanddate.com and let it know your location to find out what time you should try looking at the sky.

Lunar eclipses don’t occur in isolation. The straight-line arrangement of Sun, Earth, and Moon presents optimum conditions for eclipses – which means that a lunar eclipse always occurs two weeks before or after a solar eclipse.

In this case, a partial solar eclipse is going to take place on 21 September 2025 – but only people in New Zealand, Antarctica, various Pacific islands, and a very thin strip of Australia’s east coast are going to be in a good position to see it. Sad trombone.