SPACE/COSMOS
Enhanced activity in the upper atmosphere of Sporadic E layers during the 2024 Mother’s Day super geomagnetic storm
New study reveals the impact of the Mother’s Day geomagnetic storm on the Sporadic E layers that could disrupt radio communications and navigation systems
Kyushu University
image:
A screen shot from NASA’s Scientific Visualization Studio that visualizes the Earth's magnetosphere being hit by a geomagnetic storm that happened throughout May 10-11, 2024. The powerful geomagnetic storm resulted in auroras being viewed in relatively low latitude areas around the globe. Kyushu University researchers found that sporadic Es were also enhanced during these storms.
view moreCredit: NASA's Scientific Visualization Studio and NASA DRIVE Science Center for Geospace Storms https://svs.gsfc.nasa.gov/5435.
Fukuoka, Japan—In a paper published in Geophysical Research Letters, researchers from Kyushu University report on the activity of sporadic E layers—about 90-120 km above sea level—during the Mother’s Day geomagnetic storm. The team found that the E layers were significantly enhanced during the recovery phase of the geomagnetic storm. Sporadic E layer, as the name suggests, is a phenomenon in which thin—about 1-5 km thick—but dense patches of ionized metals suddenly appear in the E layer of the ionosphere.
Moreover, the team found that these series of sporadic E layers occurred mainly over Southeast Asia, Australia, the South Pacific, and the East Pacific. They also observed a propagation characteristic of the phenomenon wherein the clouds were first detected around high latitude areas of the poles and then detected successively in lower latitude areas over time.
“When studying the Mother’s Day geomagnetic storm, many researchers looked at what happened in the F layer of the ionosphere. It is about 150-500 km above sea level and is where the most ionization occurs,” explains Professor Huixin Liu of Kyushu University’s Faculty of Science, who led the study. “The sporadic E layer hasn’t been studied very much during the storm because it appeared unaffected by solar storms. But we wanted to see if something as powerful as the Mother’s Day geomagnetic storm did anything to the E layer. What we found was very interesting.”
To track sporadic Es across the globe the team collected data both from the ground, using 37 ground-based radars called ionosodes, and from space, using the COSMiC-2 satellite network. This vast amount of data gave the researchers an unprecedented global map of sporadic Es activity during and after the solar storm.
“This large amount of data was critical for both detecting the presence of sporadic Es and tracking where they formed as time went by,” continues Liu. “In our analysis, we found that sporadic Es formed after the main phase of the solar storm, during what we call the recovery phase. Sporadic Es were also detected first in the higher latitude regions, around the Earth’s poles. They were then detected gradually in lower latitudes over time. This propagation characteristic from high to low latitudes suggests that sporadic E layers are most likely caused by the disturbed neutral winds in the E region.”
Understanding the activity of the E layer is vital due to its potential to disrupt radio communications in the HF and VHF bands. The research team hopes that their new findings will lead to better insights on Es layer activity and how such unique phenomena are created in the ionosphere.
“We now know that sporadic Es enhance during the recovery phase of a solar storm, so perhaps we can forecast more accurately sporadic Es using the propagation characteristics found in our study and mitigate potential communication disruptions,” concludes Liu. “We also plan to re-examine the data from other solar storms to see if we can better understand these phenomena.”
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For more information about this research, see "Sporadic-E Layer Responses to Super Geomagnetic Storm 10–12 May 2024," Lihui Qiu, Huixin Liu, Geophysical Research Letters https://doi.org/10.1029/2025GL115154
About Kyushu University
Founded in 1911, Kyushu University is one of Japan's leading research-oriented institutes of higher education, consistently ranking as one of the top ten Japanese universities in the Times Higher Education World University Rankings and the QS World Rankings. The university is one of the seven national universities in Japan, located in Fukuoka, on the island of Kyushu—the most southwestern of Japan’s four main islands with a population and land size slightly larger than Belgium. Kyushu U’s multiple campuses—home to around 19,000 students and 8000 faculty and staff—are located around Fukuoka City, a coastal metropolis that is frequently ranked among the world's most livable cities and historically known as Japan's gateway to Asia. Through its VISION 2030, Kyushu U will “drive social change with integrative knowledge.” By fusing the spectrum of knowledge, from the humanities and arts to engineering and medical sciences, Kyushu U will strengthen its research in the key areas of decarbonization, medicine and health, and environment and food, to tackle society’s most pressing issues.
Journal
Geophysical Research Letters
Method of Research
Data/statistical analysis
Subject of Research
Not applicable
Article Title
Sporadic-E Layer Responses to Super Geomagnetic Storm 10–12 May 2024
Universe decays faster than thought, but still takes a long time
Radboud University Nijmegen
image:
Artistic impression of a neutron star that is 'evaporating' slowly via Hawking-like radiation
view moreCredit: (c) Daniëlle Futselaar/artsource.nl
The research by black hole expert Heino Falcke, quantum physicist Michael Wondrak, and mathematician Walter van Suijlekom (all from Radboud University, Nijmegen, the Netherlands) is a follow-up to a 2023 paper by the same trio. In that paper, they showed that not only black holes, but also other objects such as neutron stars can 'evaporate' via a process akin to Hawking radiation. After that publication, the researchers received many questions from inside and outside the scientific community about how long the process would take. They have now answered this question in the new article.
Ultimate end
The researchers calculated that the end of the universe is about 10^78 years away (a 1 with 78 zeros), if only Hawking-like radiation is taken into account. This is the time it takes for white dwarf stars, the most persistent celestial bodies, to decay via Hawking-like radiation. Previous studies, which did not take this effect into account, put the lifetime of white dwarfs at 10^1100 years (a 1 with 1100 zeros). Lead author Heino Falcke: "So the ultimate end of the universe comes much sooner than expected, but fortunately it still takes a very long time."
The researchers did the calculations dead-seriously and with a wink. The basis is a reinterpretation of Hawking radiation. In 1975, physicist Stephen Hawking postulated that, contrary to the theory of relativity, particles and radiation could escape from a black hole. At the edge of a black hole, two temporary particles can form, and before they merge, one particle is sucked into the black hole and the other particle escapes. One of the consequences of this so-called Hawking radiation is that a black hole very slowly decays into particles and radiation. This contradicts Albert Einstein's theory of relativity, which says that black holes can only grow.
Neutron star as slow as black hole
The researchers calculated that the process of Hawking radiation theoretically also applies to other objects with a gravitational field. The calculations further showed that the 'evaporation time' of an object depends only on its density.
To the researchers' surprise, neutron stars and stellar black holes take the same amount of time to decay: 10^67 years. This was unexpected because black holes have a stronger gravitational field, which should cause them to 'evaporate' faster. "But black holes have no surface," says co-author and postdoctoral researcher Michael Wondrak, "They reabsorb some of their own radiation which inhibits the process."
Man and Moon: 10^90 years
Because the researchers were at it anyway, they also calculated how long it takes for the Moon and a human to evaporate via Hawking-like radiation. That's 10^90 years (a 1 with 90 zeros). Of course, the researchers subtly note, there are other processes that may cause humans and moon to disappear faster than calculated.
Co-author Walter van Suijlekom, professor of mathematics at Radboud University, adds that the research is an exciting collaboration of different disciplines and that combining astrophysics, quantum physics and mathematics leads to new insights. "By asking these kinds of questions and looking at extreme cases, we want to better understand the theory, and perhaps one day, we unravel the mystery of Hawking radiation."
Journal
Journal of Cosmology and Astroparticle Physics
Article Title
Universe decays faster than thought, but still takes a long time
Article Publication Date
12-May-2025
Scientists precisely simulate turbulence in the Galaxy — it doesn’t behave like they thought
Turbulence on the Galactic Scales
Princeton University
image:
This composite image combines observations from the NASA/ESA/CSA James Webb Space Telescope of the Phantom Galaxy (M74) with a high-resolution simulation of galactic turbulence. The simulation from this study — zoomed into a small patch of the galaxy’s interstellar medium — reveals extremely high-resolution chaotic motions of plasma that regulate star formation, structure formation, and the magnetic field across the galactic scales.
An international team of scientists have developed the world’s largest-ever simulations of magnetized turbulence and measured — with unprecedented precision — how turbulent energy moves across a vast range of scales. By simulating galactic-type turbulence in exquisite detail, the researchers found significant departures from the models that have guided astrophysical theory for decades. The findings could reshape how scientists understand the turbulent structure of the Galaxy, the transport of high-energy particles, and even the birth of stars. In practical terms, understanding and properly modeling turbulence and the production of highly energetic particles can shed light on how to safely navigate space, at a time when commercial space flight is growing and attracting the interest of civilians and celebrities alike.
view more
Credit: Credit: ESA/Webb, NASA & CSA, J. Lee and the PHANGS-JWST Team; Acknowledgement: J. Schmidt; Simulation: J. Beattie.
From the ocean’s rolling swells to the bumpy ride of a jetliner, turbulence is everywhere. It breaks large waves into smaller ones, cascading energy across scales. It is ubitquitous throughout our Galaxy and the broader Universe, shaping the behavior of plasma, stars, and magnetic fields. Yet despite its ubiquity, turbulence remains one of the greatest unsolved problems in physics.
Now, by developing the world’s largest-ever simulations of magnetized turbulence, an international team of scientists has measured — with unprecedented precision — how turbulent energy moves across a vast range of scales. The result: it doesn’t match with long-standing theories.
James Beattie, a postdoctoral researcher at Princeton University's Department of Astrophysical Sciences and a fellow at the Canadian Institute for Theoretical Astrophysics at University of Toronto, led the study along with Amitava Bhattacharjee of Princeton, and colleagues at the Australian National University, Heidelberg University and the Leibniz Supercomputing Center.
By simulating galactic-type turbulence in exquisite detail, the researchers found significant departures from the models that have guided astrophysical theory for decades. The team explicitly observed that magnetic fields alter the way energy cascades through the space between stars in our Galaxy — known as the interstellar medium — suppressing small-scale motions and enhancing certain wave-like disturbances known as Alfvén waves. The findings could reshape how scientists understand the turbulent structure of the Galaxy, the transport of high-energy particles, and even the turbulent birth of stars.
In practical terms, understanding and properly modeling turbulence and the production of highly energetic particles can shed light on how to safely navigate space, at a time when commercial space flight is growing and attracting the interest of civilians and celebrities alike.
‘‘The research has implications for predicting and monitoring space weather to better understand the plasma environment around satellites and future space missions, and also the acceleration of highly energetic particles, which damage everything, and could endanger human beings in space,” said Bhattacharjee, a co-author on the new paper and Professor of Astrophysical Sciences at Princeton.
“A lot of these fundamental plasma turbulence questions are objects of missions now launched by NASA and have implications for understanding the origin of cosmic magnetic fields. Simulations like these would give us insights into how to interpret satellite and ground-based measurements,” said Bhattacharjee.
Simulating Turbulence like Never Before
There is still no complete mathematical framework for predicting how energy moves from large to small scales: across oceans, in the atmosphere, or through the plasma and dust between stars. In space, the problem is even more complex than on Earth due to magnetization, requiring vast computational resources to model. The team’s work relied on the equivalent of 140,000 computers running in parallel.
“To put these massive simulations into perspective: if we had started one on a single laptop when humans first domesticated animals, it would just be finishing now,” said Beattie. “Luckily, utilizing the amazing resources from the Leibniz Supercomputing Centre, we can distribute the workload across thousands of computers to accelerate the calculations.”
“We are a step closer to uncovering the true nature of astrophysical and space turbulence, from chaotic plasma near Earth to the vast motions within our Galaxy and beyond,” said Beattie, “The dream is to discover universal features in turbulence across the Universe, and we’ll continue pushing the limits of the next-generation of simulations to test that idea.”
The new work will be published in the journal Nature Astronomy on May 13, 2025. In addition to Beattie and Bhattacharjee, co-authors include Christoph Federrath of the Australian National University, Ralf S. Klessen of Heidelberg University, and Salvatore Cielo of the Leibniz Supercomputing Center of the Bavarian Academy of Sciences and Humanities.
The SuperMUC-NG supercomputer at the Leibniz Supercomputing Centre (LRZ) in Munich is one of Europe’s most powerful computing systems. It supports cutting-edge research in fields like astrophysics, life sciences, and artificial intelligence by enabling massive-scale simulations and data processing.
The supercomputers were used to develop the world's largest simulations of magnetized turbulence. The team’s work relied on the equivalent of 140,000 computers running in parallel, enabled by the Leibniz Supercomputing Centre’s supercomputer, totaling more than 80 million computing hours from start to finish. There is still no complete mathematical framework for predicting how energy moves from large to small scales — across oceans, in the atmosphere, or through the plasma and dust between the stars. In space, the problem is even more complex than on Earth due to magnetization, requiring these computational resources to model.
Credit
Image credit: F. Löchner / LRZ
A snapshot of the chaotic dance between plasma and magnetic fields in the world’s largest simulation of magnetized turbulence — the type of turbulence found throughout our Galaxy. The work includes the largest and most precise simulations ever made of galactic turbulence.
This 2D slice of the world's largest turbulence simulation reveals the fractal structure of the density, shown in yellow, black and red, and magnetic field, shown in white.
The chaotic structure of the turbulent magnetic field and velocity in the world’s largest magnetized turbulence simulation, a model for plasma motion within our Galaxy.
Credit
James Beattie
Journal
Nature Astronomy
Method of Research
Computational simulation/modeling
Subject of Research
Not applicable
Article Title
The spectrum of magnetized turbulence in the interstellar medium
Article Publication Date
13-May-2025
Astrophysicist searches for gravitational waves in new way
University of Colorado at Boulder
University of Colorado Boulder astrophysicist Jeremy Darling is pursuing a new way of measuring the universe’s gravitational wave background—the constant flow of waves that churn through the cosmos, warping the very fabric of space and time.
The research, published in The Astrophysical Journal Letters, could one day help to unlock some of the universe’s deepest mysteries, including how gravity works at its most fundamental level.
“There is a lot we can learn from getting these precise measurements of gravitational waves,” said Darling, professor in the Department of Astrophysical and Planetary Sciences. “Different flavors of gravity could lead to lots of different kinds of gravitational waves.”
To understand how such waves work, it helps to picture Earth as a small buoy bobbing in a stormy ocean.
Darling explained that, throughout the history of the universe, countless supermassive black holes have engaged in a volatile dance: These behemoths spiral around each other faster and faster until they crash together. Scientists suspect that the resulting collisions are so powerful they, literally, generate ripples that spread out into the universe.
This background noise washes over our planet all the time, although you’d never know it. The kinds of gravitational waves that Darling seeks to measure tend to be very slow, passing our planet over the course of years to decades.
In 2023, a team of scientists belonging to the NANOGrav collaboration achieved a coup by measuring that cosmic wave pool. The group recorded how the universe’s gravitational wave background stretched and squeezed spacetime, affecting the light coming to Earth from celestial objects known as pulsars, which act somewhat like cosmic clocks.
But those detailed measurements only captured how gravitational waves move in a single direction—akin to waves flowing directly toward and away from a shoreline. Darling, in contrast, wants to see how gravitational waves also move from side-to-side and up and down compared to Earth.
In his latest study, the astrophysicist got help from another class of celestial objects: quasars, or unusually bright, supermassive black holes sitting at the centers of galaxies. Darling searches for signals from gravitational waves by precisely measuring how quasars move compared to each other in the sky. He hasn’t spotted those signals yet, but that could change as more data become available.
“Gravitational waves operate in three dimensions,” Darling said. “They stretch and squeeze spacetime along our line of sight, but they also cause objects to appear to move back and forth in the sky.”
Galaxies in motion
The research drills down on the notoriously tricky task of studying how celestial objects move, a field known as astrometry.
Darling explained that quasars rest millions of light-years or more from Earth. As the glow from these objects speeds toward Earth, it doesn’t necessarily proceed in a straight line. Instead, passing gravitational waves will deflect that light, almost like a baseball pitcher throwing a curve ball.
Those quasars aren’t actually moving in space, but from Earth, they might look like they are—a sort of cosmic wiggling happening all around us.
“If you lived for millions of years, and you could actually observe these incredibly tiny motions, you’d see these quasars wiggling back and forth,” Darling said.
Or that’s the theory. In practice, scientists have struggled to observe those wiggles. In part, that’s because these motions are hard to observe, requiring a precision 10 times greater than it would take to watch a human fingernail growing on the moon from Earth. But our planet is also moving through space. Our planet orbits the sun at a speed of roughly 67,000 miles per hour, and the sun itself is hurtling through space at a blistering 850,000 miles per hour.
Detecting the signal from gravitational waves, in other words, requires disentangling Earth’s own motion from the apparent motion of quasars. To begin that process, Darling drew on data from the European Space Agency’s Gaia satellite. Since Gaia’s launch in 2013, its science team has released observations of more than a million quasars over about three years.
Darling took those observations, split the quasars into pairs, then carefully measured how those pairs moved relative to each other.
His findings aren’t detailed enough yet to prove that gravitational waves are making quasars wiggle. But, Darling said, it’s an important search—unraveling the physics of gravitational waves, for example, could help scientists understand how galaxies evolve in our universe and help them test fundamental assumptions about gravity.
The astrophysicist could get some help in that pursuit soon. In 2026, the Gaia team plans to release five-and-a-half more years of quasar observations, providing a new trove of data that might just reveal the secrets of the universe’s gravitational wave background.
“If we can see millions of quasars, then maybe we can find these signals buried in that very large dataset,” he said.
Journal
The Astrophysical Journal Letters
Article Title
A New Approach to the Low-frequency Stochastic Gravitational-wave Background: Constraints from Quasars and the Astrometric Hellings–Downs Curve
In-situ atmospheric thermoelectric conversion on Mars
Preparing for human Mars exploration
Science China Press
image:
(a) Directly driving Martian gas thermoelectric conversion to satisfy the Mars surface energy demands. (b) The thermophysical properties of Martian gas compared to conventional rare gases. The symbol P and T represent the operating pressure and temperature, respectively. (c) The type of working pattern suitable for native Martian gas thermoelectric conversion. The closed subcritical cycle is the most suitable choice on Mars.
view moreCredit: ©Science China Press
1. Martian gas driven thermoelectric conversion
The Martian atmosphere (95.7% CO2, 2.7% N2, and 1.6% Ar) as a working medium represents an unprecedented concept for dynamic thermoelectric conversion. The abundant in-situ atmospheric resources enhance the tolerance of moving components to gas leakage in extreme operating environments. The characteristics of Martian gases, such as their large molecular weight and high thermal stability, contribute to ensuring safety and increasing power density. Martian gases are better suited to operate in the subcritical state, similar to the behavior of rare gases. Beyond electricity generation, Martian gas-driven thermoelectric conversion holds expanded application potential, including coupling with Solid Oxide Electrolysis Cells (SOEC) for in-situ oxygen production and heating.
2. Environmental suitability and technology potential
Martian atmosphere shows promising thermoelectric conversion properties, matching the temperature range for microreactor secondary loops. In-situ conversion can maintain 90% of designed power during day-night temperature fluctuations. Even with full dust coverage, the system retains 39% to 46% of its initial power. Efficiency could improve by 7.4% to 20.0%, and power density by 1.0% to 14.2%, compared to rare gases. Notably, conversion efficiency can exceed 22% at hot-end temperatures below 973 K. When power demands exceed 100 kW, such as for Mars base outposts, in-situ conversion offers significant weight reduction, with over twice the efficiency of traditional thermoelectric materials, reducing the scale of microreactors and radiators.
Journal
Science Bulletin
Method of Research
Computational simulation/modeling
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