SPACE/COSMOS
Out-of-this-world ice geysers
Simulations show Saturn’s moon Enceladus shoots less ice into space than previous estimates
University of Texas at Austin
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Saturn's icy moon Enceladus loses ice mass to space by cryovolcanic geyers, and new TACC supercomputer simulations have improved estimates of ice mass loss. These findings help with understanding and future robotic exploration of what’s below the surface of the icy moon, which might harbor life.
view moreCredit: NASA
In the 17th century, astronomers Christiaan Huygens and Giovanni Cassini trained their telescopes on Saturn and uncovered a startling truth: the planet’s luminous bands were not solid appendages, but vast, separate rings composed of countless nested arcs.
Centuries later, NASA’s Cassini–Huygens (Cassini) probe carried the exploration of Saturn even further. Beginning in 2005, it sent back a stream of spectacular images that transformed scientists’ understanding of the system. Among its most dramatic revelations were the towering geysers on Saturn’s icy moon Enceladus, which blasted debris into space and left behind a faint sub-ring encircling the planet.
New supercomputer simulations from the Texas Advanced Computing Center (TACC) based on the Cassini space probe’s data have found improved estimates of ice mass Enceladus is losing to space. These findings help with understanding and future robotic exploration of what’s below the surface of the icy moon, which might harbor life.
“The mass flow rates from Enceladus are between 20 to 40 percent lower than what you find in the scientific literature,” said Arnaud Mahieux, a senior researcher at the Royal Belgian Institute for Space Aeronomy and an affiliate of the UT Austin Department of Aerospace Engineering & Engineering Mechanics.
Supercomputers to Enceladus
Mahieux is the corresponding author of a computational study of Enceladus published August 2025 in the Journal of Geophysical Research: Planets. In it, he and colleagues developed Direct Simulation Monte Carlo (DSMC) models that improve understanding of the structure and behavior of enormous plumes of water vapor and icy particles ejected by vents on the Enceladus surface.
This study builds on prior work published in 2019 and led by Mahieux that first used DSMC models to derive the initial conditions that create the icy plumes, such as vent size, ratio of water vapor to ice grains, temperature, and the speed of exit.
“DSMC simulations are very expensive," Mahieux said.
"We used TACC supercomputers back in 2015 to obtain the parameterizations to reduce computation time from 48 hours then to just a few milliseconds now.”
Using mathematical parameterizations, researchers calculated the density and velocity of Enceladus’s cryovolcanic plumes, drawing on data Cassini gathered as it flew directly through them.
“The main finding of our new study is that for 100 cryovolcanic sources, we could constrain the mass flow rates and other parameters that were not derived before, such as the temperature at which the material was exiting. This is a big step forward in understanding what’s happening on Enceladus,” Mahieux said.
Enceladus is a tiny world, just 313 miles across, whose weak gravity cannot hold back the icy jets erupting from its vents. This is properly accounted for in these DSMC models. Earlier approaches were less sophisticated in their physics and gas dynamics than our DSMC model. What Enceladus does is akin to a volcano hurling lava into space—except the ejecta are plumes of water vapor and ice.
The simulations model how gas in the plume moves at the micro level, where particles move, collide, and exchange energy like marbles hitting each other in a game. Several millions of molecules are simulated on microsecond time steps, and the DSMC models allow calculations at a lower, more realistic pressure than before, with longer travel time between collisions.
David Goldstein, UT Austin professor and study co-author, led development in 2011 of the DSMC code called Planet. TACC awarded Goldstein allocations on the Lonestar6 and Stampede3 supercomputers through The University of Texas Research cyberinfrastructure portal, which supports researchers at all 14 UT system institutions.
“TACC systems have a wonderful architecture that offer a lot of flexibility," Mahieux said. "If we’re using the DSMC code on just a laptop, we could only simulate tiny domains. Thanks to TACC, we can simulate from the surface of Enceladus up to 10 kilometers of altitude, where the plumes expand into space.”
Saturn dwells beyond what astronomers call the ‘snow line’ in the solar system joining other planets with icy moons such as Jupiter, Uranus, and Neptune.
“There is an ocean of liquid water under these ‘big balls of ice,’" Mahieux said. "These are many other worlds, besides the Earth, which have a liquid ocean. The plumes at Enceladus open a window to the underground conditions."
NASA and the European Space Agency are planning future missions to revisit Enceladus, with ambitions that go far beyond flybys. Proposals include landing on the moon’s surface and drilling through its crust to probe the ocean below, a search for signs of life hidden beneath miles of ice. Understanding and measuring the content of the Enceladus plumes gives us a way of actually measuring what is happening below the surface without drilling through the ice.
“Supercomputers can give us answers to questions we couldn’t dream of asking even 10 or 15 years ago," Mahieux said. "We can now get much closer to simulating what nature is doing."
Enceladus simulations were performed on the Lonestar6 (left) and Stampede3 (right) supercomputers of the Texas Advanced Computing Center, allocated through awards by the University of Texas Research Cyberinfrastructure Portal.
Credit
TACC
Journal
Journal of Geophysical Research Planets
Method of Research
Computational simulation/modeling
Subject of Research
Not applicable
Article Title
Enceladus Water Plume Modeling Using DSMC
Far side of the moon may be colder than the near side
University College London
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Images of the near (left) and far side of the moon from NASA's Clementine mission.
view moreCredit: NASA
The interior of the mysterious far side of the moon may be colder than the side constantly facing Earth, suggests a new analysis of rock samples co-led by a UCL (University College London) and Peking University researcher.
The study, published in the journal Nature Geoscience, looked at fragments of rock and soil scooped up by China’s Chang’e 6 spacecraft last year from a vast crater on the far side of the moon.
The research team confirmed previous findings that the rock sample was about 2.8 billion years old, and analysed the chemical make-up of its minerals to estimate that it formed from lava deep within the moon’s interior at a temperature of about 1,100 degrees C – about 100 degrees C cooler than existing samples from the near side.
Co-author Professor Yang Li, based at UCL’s Department of Earth Sciences and Peking University, said: “The near side and far side of the moon are very different at the surface and potentially in the interior. It is one of the great mysteries of the moon. We call it the two-faced moon. A dramatic difference in temperature between the near and far side of the mantle has long been hypothesised, but our study provides the first evidence using real samples.”
Co-author Mr Xuelin Zhu, a PhD student at Peking University, said: “These findings take us a step closer to understanding the two faces of the moon. They show us that the differences between the near and far side are not only at the surface but go deep into the interior.”
The far side has a thicker crust, is more mountainous and cratered, and appears to have been less volcanic, with fewer dark patches of basalt formed from ancient lava.
In their paper, the researchers noted that the far side of the interior may have been cooler due to having fewer heat-producing elements – elements such as uranium, thorium and potassium, which release heat due to radioactive decay.
Previous studies have suggested that this uneven distribution of heat-producing elements might have occurred after a massive asteroid or planetary body smashed into the far side, shaking up the moon’s interior and pushing denser materials containing more heat-producing elements across to the near side.
Other theories are that the moon might have collided with a second, smaller moon early in its history, with near-side and far-side samples originating from two thermally different moonlets, or that the near side might be hotter due to the tug of Earth’s gravity.
For the new study, the research team analysed 300 g of lunar soil allocated to the Beijing Research Institute of Uranium Geology. Sheng He, first author from the institute, explained: “The sample collected by the Chang’e 6 mission is the first ever from the far side of the moon.” The team mapped selected parts of the sample, made up largely of grains of basalt, with an electron probe*, to determine its composition.
The researchers measured tiny variations in lead isotopes using an ion probe** to date the rock as 2.8 billion years old (a technique relying on the fact that uranium decays into lead at a steady rate). The data were processed using a method refined by Professor Pieter Vermeesch of UCL Earth Sciences.
They then used several techniques to estimate the temperature of the sample while at different stages of its past when it was deep in the moon’s interior.
The first was to analyse the composition of minerals and compare these to computer simulations to estimate how hot the rock was when it formed (crystallised). This was compared to similar estimates for near-side rocks, with a difference of 100 degrees C.
The second approach was to go back further in the sample’s history, inferring from its chemical make-up how hot its “parent rock” would have been (i.e., before the parent rock melted into magma and later solidified again into the rock collected back by Chang’e 6), comparing this to estimates for near-side samples collected by the Apollo missions. They again found about a 100 degrees C difference.
As returned samples are limited, they worked with a team from Shandong University to estimate parent rock temperatures using satellite data of the Chang’e landing site on the far side, comparing this with equivalent satellite data from the near side, again finding a difference (this time of 70 degrees C).
On the moon, heat-producing elements such as uranium, thorium and potassium tend to occur together alongside phosphorus and rare earth elements in material known as “KREEP”-rich (the acronym derives from potassium having the chemical symbol K, rare-earth elements (REE), and P for phosphorus).
The leading theory of the moon’s origin is that it formed out of debris created from a massive collision between Earth and a Mars-sized protoplanet, and began wholly or mostly made of molten rock (lava or magma). This magma solidified as it cooled, but KREEP elements were incompatible with the crystals that formed and thus stayed for longer in the magma. Scientists would expect the KREEP material to be evenly spread across the moon. Instead, it is thought to be bunched up in the near side mantle. The distribution of these elements may be why the near side has been more volcanically active.
Although the present temperature of the far and near side of the moon’s mantle is not known from this study, any imbalance in temperature between the two sides will likely persist for a very long time, with the moon cooling down very slowly from the moment it formed from a catastrophic impact. However, the research team are currently working on getting a definitive answer to this question.
*An electron probe fires a concentrated beam of electrons at a sample. This induces the sample to emit X-rays. The pattern of these X-rays can be analysed to identify the elements that make up the sample.
**The ion probe, or Secondary Ion Mass Spectrometry (SIMS), fires a beam of ions at a sample. This knocks secondary ions off the sample’s surface. The pattern of these ions, including for instance isotopes of elements like lead, can be analysed to determine how many atoms of each isotope are present.
Journal
Nature Geoscience
Research discover new landslides formed since 2009 on the Moon, recognizing endogenic moonquakes rather than new impacts are the primary trigger
Active landslides on the Moon
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Change detection conducted in the youngest, topographically steepest, and theoretically most unstable regions on the lunar surface revealed a large number of new landslides formed since 2009. Endogenic moonquakes rather than new impacts are the primary trigger, and the Imbrium basin may host an active seismic zone.
view moreCredit: Zhouxuan XIAO
The research team, led by Professor Zhiyong Xiao from Sun Yat-sen University, along with colleagues from Fuzhou University and Shanghai Normal University, searched for short-term changes on the surface of the Moon using multi-temporal images obtained from 2009–2024. Their findings showed that most new landslides on the Moon were triggered by endogenic moonquakes, rather than by new impacts or thermal weathering of slope rocks, which could transform the knowledge of lunar surface processes and offer critical guidance for preventing potential geohazards to future lunar surface exploration and constructions.
For decades, scientists have sought to clarify what causes the widespread landslides on the Moon—a key process shaping its topography and an understudied potential geohazard for lunar surface exploration. Prevailing assumptions include both internal and external forces: endogenic moonquakes with various energy sources such as tides, cosmic impacts that induce near-field and far-field disturbances, and thermal weathering that possibly breakdown rocks due to the extreme diurnal temperature variations. However, limited observations of active landslides on the Moon left uncertainties about the activity level and potential triggers—a gap the new study aims to fill.
“Worldwide lunar exploration is accelerating, with plans for permanent research stations and deep-space outposts,” explains Dr. Xiao, lead author and researcher at Sun Yat-sen University’s Planetary Environmental and Astrobiological Research Laboratory. “Understanding today’s landslide activity and its drivers is essential for assessing geohazard risks to these future missions.”
To capture new landslides, the team targeted the Moon’s “least stable regions”—areas most prone to mass wasting, including young impact crater walls, fault-formed wrinkle ridges, and irregular mare patches that are potential sites of recent volcanic activity. New landslides in these areas would represent the current activity level on the Moon. They analyzed 562 pairs of high-resolution temporal images for 74 observation targets, evenly distributed at the Moon’s near and far sides to ensure results were representative of global conditions. With image resolution good enough to capture subtle surface changes, the researchers refined image analysis techniques to avoid false detection: they used precise co-registration to align before-and-after images and controlled for lighting differences.
In total, the team discovered 41 new landslides, a number comparable to that discovered by an earlier endeavour of global automatic search. The landslides are less than 1 km long, 100 m wide, and less than 1 meter thick, with volumes under 100,000 cubic meters—far smaller than large, ancient lunar landslides. They form on slopes of 24°–42°, near the angle of repose for lunar terrains, where loose material is most unstable. Boulders are not visible in the initiation zones of the landslides, and pervasive boulders on steep slopes did not yield landslides neither. Only 29% (12 of 41) of the new landslides were possibly linked to new impacts, as the new impacts occurred right in the initiation zones of the landslides. However, more than 2000 new impacts have been observed on the Moon, but only dozens of new landslides were discovered, suggesting that new impacts are not an efficient driver of current landslide on the Moon. The team also found that even larger recent impacts (up to 75 meters wide, among the biggest formed in the past 15 years) failed to trigger landslides on nearby steep slopes, confirming that new impacts have a low efficiency of triggering landslides.
The team found that 71% (29 of 41) of the new landslides had no connection to impacts or exposed rocks, leaving endogenic moonquakes as the only possible driver—consistent with the Moon’s interior containing molten portions. These landslides cluster in the eastern Imbrium Basin—a 3.92-billion-year-old impact basin, consistent with known zones of shallow moonquakes recorded by the Apollo seismometers, suggesting this area is a currently active lunar seismic zone.
By showing endogenic moonquakes dominate triggers of current lunar landslides, the research challenges traditional models and highlights the need to prioritize internal lunar activity in studies of its surface evolution. The spatial distribution of active landslides may serve as a “proxy” for subsurface seismic activity—helping scientists map hidden lunar earthquake zones without deploying seismometers everywhere. While the small, localized landslides might pose limited overall geohazard risks, they warn against placing slope-proximal facilities in seismically active areas like the eastern Imbrium Basin. The basin also emerges as a priority site for deploying seismometers and thermal probes to study the Moon’s interior dynamics.
“Our work reminds us the Moon is not a static, dead world—besides abundant new impacts, landslide is active today,” says Dr. Xiao. “These insights bridge a gap between past lunar history and present-day processes, advancing both science and mission planning.”
Journal
National Science Review
Method of Research
Observational study
Mapping the universe just got easier
With new emulator, cosmologists can explore data faster than thought possible
As the study of the universe evolves and the data sets get larger and more complex, a new breakthrough means researchers can analyze huge data sets with just a laptop and a few hours.
Dr. Marco Bonici, a postdoctoral fellow at the Waterloo Centre for Astrophysics at the University of Waterloo, led an international team that designed Effort.jl, which stands for EFfective Field theORy surrogate. The device combines state-of-the-art numerical methods and clever preprocessing strategies to achieve exceptional computational performance with the precision needed in the field of cosmology. The team designed this novel and efficient emulator for the Effective Field Theory of Large-Scale Structure (EFTofLSS) to analyze data sets faster than ever before.
Bonici came up with the idea to create the emulator after spending hundreds of hours throughout his career running multiple computational models every time a change was made to the parameters. Often, one small change could lead to days of additional computational analysis, making it a slow process that required a lot of time and patience, and sometimes came at a high cost.
“Using Effort.jl, we can run through complex data sets on models like EFTofLSS, which have previously needed a lot of time and computer power,” Bonici said. “With projects like DESI and Euclid expanding our knowledge of the universe and creating even larger astronomical datasets to explore, Effort.jl allows researchers to analyze data faster, inexpensively and multiple times while making small changes based on nuances in the data.”
Emulators are trained shortcuts that mimic the behaviour of the full and expensive simulations, but run much faster, empowering scientists to test multiple cosmic scenarios without waiting hours for each one. Emulators also make it possible to use advanced techniques like gradient-based sampling to explore complex models efficiently.
“We were able to validate the predictions coming out of Effort.jl by aligning them with those coming out of EFTofLSS,” Bonici said. “The margin of error was small and showed us that the calculations coming out of Effort.jl are strong. Effort.jl can also handle observational quirks like distortions in data and can be customized very easily to the needs of the researcher.”
As smart as this tool is, it won’t replace the physics knowledge of the cosmologists who input and interpret the data. While the tool can make predictions, the knowledge from the researchers and the parameters they set make it truly powerful.
Looking ahead, Effort.jl is poised to analyze next-generation cosmological datasets and to support joint analyses with complementary tools. Possible future applications include weather and climate forecasting.
The paper, Effort.jl: a fast and differentiable emulator for the Effective Field Theory of the Large Scale Structure of the Universe, appears in the Journal of Cosmology and Astroparticle Physics.
Journal
Journal of Cosmology and Astroparticle Physics
Method of Research
Computational simulation/modeling
Subject of Research
Not applicable
Article Title
Effort.jl: a fast and differentiable emulator for the Effective Field Theory of the Large Scale Structure of the Universe
Article Publication Date
26-Sep-2025
More accurate computer models open up the early universe
University of Jyväskylä - Jyväskylän yliopisto
image:
Simulated gluon field in the nucleus. When energy increases, the nucleus grows and its internal structure changes.
view moreCredit: Picture: Björn Schenke.
A researcher Heikki Mäntysaari from the University of Jyväskylä (Finland), has been part of an international research group that has made significant advances in modeling heavy ion collisions. New computer models provide additional information about the matter in the early universe and improve our understanding of the extremely hot and dense nuclear matter.
When atomic nuclei collide at near light speed, they form a new state of matter where quarks and gluons are liberated from protons and neutrons. To study this matter, called a quark–gluon plasma (QGP), scientists need to understand the initial conditions, including the shape and energy density of the created matter.
Quark-gluon plasma tells the story of the early universe
The University of Jyväskylä has participated in international research that has improved computer models that simulate these initial conditions along with the entire collision dynamics. Researchers solved equations that describe how the internal structure of the colliding protons and nuclei changes with collision energy. The updated models match patterns of particles produced by the collisions better than older ones, giving a clearer view of the QGP’s birth.
- This research helps reveal how nuclear matter behaves under extreme conditions, like those that existed just after the Big Bang. By making models of these collisions more accurate, we can better measure the properties of the QGP, says Associate Professor Heikki Mäntysaari from the University of Jyväskylä, who participated in the research.
Research is moving forward with experimental and theoretical collaboration
The new models better correspond to experimental measurements made at Brookhaven National Laboratory (BNL) and the European Organization for Nuclear Research (CERN).
- By connecting experimental results with theoretical advances, the study opens the door to more precise extraction of quark–gluon plasma properties, improving our understanding of matter under extreme conditions. We are also eagerly waiting for the new Electron-Ion Collider which will start to operate at Brookhaven in 2030s, providing complementary measurements, explains Mäntysaari.
Jyväskylä's quark research on the international forefront
The University of Jyväskylä is home to a world-class the Centre of Excellence in Quark Matter funded by the Research Council of Finland. The ultimate goal is to understand one of the four fundamental forces of nature: the strong interaction between the fundamental building blocks of ordinary matter, quarks and gluons.
- International research collaboration is crucial, especially when combining experimental and theoretical knowledge. Experiments are becoming increasingly complex, which is why it is more important than ever that all parties understand what is being measured and how phenomena are modeled theoretically. This is also the main motivation behind our Centre of Excellence: it brings together theorists and experimentalists performing measurements at CERN. This shared understanding is key to advancing the field, points Mäntysaari.
The Research Council of Finland and the European Research Council (ERC) supported this research.
Method of Research
Computational simulation/modeling
Subject of Research
Not applicable
Article Title
Collision-Energy Dependence in Heavy-Ion Collisions from Nonlinear QCD Evolution
Laboratory breakthrough recreating star formation mechanism wins prestigious John Dawson Award
First successful recreation of cosmic process validates astrophysical theory
image:
The winners of the 2025 John Dawson Award for Excellence in Plasma Physics Research: Hantao Ji, Jeremy Goodman, Fatima Ebrahimi, Yin Wang and Erik Gilson.
view moreCredit: Michael Livingston / PPPL Communications Department
Groundbreaking scientific findings on how swirling matter can form stars, planets and supermassive black holes earned a team of scientists from the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) and Princeton University the 2025 John Dawson Award for Excellence in Plasma Physics Research from the American Physical Society (APS).
The winning team includes Fatima Ebrahimi, Erik Gilson, Hantao Ji and Yin Wang, as well as Princeton University’s Jeremy Goodman. The award recognizes a series of breakthroughs in understanding and recreating a process involving disks of swirling matter in space that wobble in a very specific way. The process leads to turbulence, which causes matter to spiral inward, ultimately forming massive objects in space.
“Without this dynamic process, stars would not form, and planets and even humankind would not exist,” explained Ji, one of the lead researchers on the project and a principal investigator at PPPL. “It is a very critical process, only possible due to the presence of plasma and magnetic fields: two areas of which PPPL has scientific expertise. The combination of plasma and magnetic fields allows the wobble to happen, which, in turn, enables the formation of stars and planets, and therefore, life itself.”
The team’s achievement culminates more than two decades of persistent effort, combining experimental ingenuity, theoretical insight and advanced computational modeling. Their focus was on an uneven wobble known as magnetorotational instability (MRI). It has long been theorized that this type of wobble can form planets and stars. The team was the first to study it theoretically and then recreate the process in a laboratory setting.
“These findings help us to prove that, yes, these predicted instabilities actually do exist,” said Ebrahimi, a principal research physicist at PPPL’s Theory Department.
Recreating outer space in a lab
Reproducing MRI at the Laboratory proved exceptionally challenging. Unlike the vast, edge-free environment of outer space, lab experiments must be contained. The cylindrical container introduces an edge that can interfere with the instability. Years of effort were required to minimize these edge effects and isolate the true astrophysical phenomena, making the experimental demonstration of MRI a major scientific achievement.
“It was a new adventure for all of us,” said Goodman, Princeton University professor of astrophysical sciences and co-lead on the research. The adventure began after Ji asked Goodman to give a talk on astrophysics at PPPL. “We just kept at it for 20-plus years.”
Erik Gilson, head of PPPL’s discovery plasma science, puts his fingers into a vat of liquid metal. (Photo credit: Michael Livingston / PPPL Communications Department)
Advancing PPPL’s liquid metals expertise
In space, MRI involves plasma. However, plasma wasn’t practical for studying MRI at the Lab, so liquid metals were used instead. Liquid metals were ideal because they flow like water and conduct electricity. By putting the liquid metals in specially designed, nested cylinders, the scientists were able to precisely adjust the rotation speeds and magnetic field strengths so the MRI could be isolated and studied. MRI research has been a key part of developing PPPL’s liquid metal expertise over the last few decades. Liquid metals are also being investigated for use in fusion systems, with many PPPL researchers working on the best ways to use them.
“The partnerships with Princeton University’s Department of Astrophysics and the resources and expertise here at PPPL are what have made it possible to bring a cosmic process down to Earth and study it in the lab,” said Gilson, head of PPPL’s discovery plasma science.
Wang, a PPPL staff research physicist, joined the team in 2019, contributing to a project that already had more than a decade of progress. He described the achievement as a true team success. “I learned a lot from the collaborative work, and I am honored to share this award with my colleagues,” he said.
All team members said they are excited to continue working on this research, including the theoretical and experimental aspects. “We would love to push the system harder, whether that means more magnetic field, faster spinning or building a larger system,” Gilson said.
Erik Gilson, head of PPPL’s discovery plasma science, puts his fingers into a vat of liquid metal.
Credit
Michael Livingston / PPPL Communications Department
PPPL has a long history of APS award wins
The John Dawson Award was established to honor recent outstanding achievements in plasma physics. The team will receive the Dawson Award at the annual meeting of the APS Division of Plasma Physics this November in Long Beach, California. The award includes $5,000 shared among the recipients and support for travel and registration to the annual meeting.
“PPPL has built a remarkable legacy of excellence recognized by the American Physical Society,” said Lab Director Steven Cowley. “This latest win further solidifies our reputation as leaders in plasma physics research.”
PPPL’s excellence in plasma physics research has been consistently recognized by APS. The Lab’s researchers have claimed the John Dawson Award multiple times in recent years, with Hong Qin receiving the honor in 2023 and William Fox in 2020.
The Lab’s legacy extends to the APS James Clerk Maxwell Prize for Plasma Physics, beginning with PPPL founder Lyman Spitzer, who received the inaugural award in 1975. This year’s winner of the Maxwell Prize is William Heidbrink, a PPPL alumnus now at the University of California-Irvine. Greg Hammett and former Associate Laboratory Director Bill Dorland shared the prize in 2024. Many other PPPL researchers have also earned the Maxwell Prize over the years, including Nathaniel Fisch, Russell Kulsrud, Amitava Bhattacharjee and Masaaki Yamada.
Collaborators on the MRI project include Michael Burin, Kyle Caspary, Dahan Choi, Eric Edlund, Christophe Gissinger, Frank Jenko, Akira Kageyama, Karl Lackner, Wei Liu, Mark Nornberg, Austin Roach, Ethan Schartman, Erik Spence, Xing Wei and Himawan Winarto. The project has been supported by the DOE Fusion Energy Sciences’ General Plasma Science program through grants and collaborations under the Max-Planck-Princeton Center for Fusion and Astro Plasma Physics and the Center for Momentum Transport and Flow Organization in Plasmas and Magnetofluids, the National Science Foundation (NSF) Division of Astronomical Sciences and the NSF Division of Physics through collaboration under the Physics Frontier Center for Magnetic Self-Organization and the NASA Astrophysics Research and Analysis Program.
PPPL is mastering the art of using plasma — the fourth state of matter — to solve some of the world’s toughest science and technology challenges. Nestled on Princeton University’s Forrestal Campus in Plainsboro, New Jersey, our research ignites innovation in a range of applications including fusion energy, nanoscale fabrication, quantum materials and devices, and sustainability science. The University manages the Laboratory for the U.S. Department of Energy’s Office of Science, which is the nation’s single largest supporter of basic research in the physical sciences. Feel the heat at https://energy.gov/science and https://www.pppl.gov
Kyushu University launches Quantum and Spacetime Research Institute
The institute will act as a catalyst for research and education, tackling the unexplored frontier of quantum and gravity, and bridging the cosmos with quantum science.
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The unification of gravity and quantum mechanics has remained an unsolved problem for the last 100 years since the birth of quantum mechanics. Our institute sets its goal on shedding light on this grand challenge, striving for its resolution through the fusion of diverse fields.
view moreCredit: Kyushu University
Fukuoka, Japan—On October 1, 2025, Kyushu University will launch the Quantum and Spacetime Research Institute, a new hub dedicated to researching the unexplored frontier between quantum science and space science. Bringing together researchers from inside and outside the university, the institute will foster interdisciplinary collaboration, advancing both fundamental and applied science.
The term “spacetime” symbolizes the unification of time and space, representing gravity and the universe. While quantum mechanics celebrates its 100th anniversary, the unification of gravity and quantum theory remains unresolved. The Institute will confront this challenge by pursuing the quantum–gravity crossover, while also serving as a platform to broadly connect quantum science with the universe.
“The fusion of space and quantum science holds the key to unlocking unknown physical laws and pioneering new technologies,” says Professor Kazuhiro Yamamoto of the Faculty of Science. “Through research that connects to the cosmic frontier, we aim to explore humanity’s future and develop discoveries and innovations that will shape it.”
Comprising six divisions and a Strategic Office, the institute will unite more than 50 researchers under an “All Kyushu University” framework, supported by strong domestic and international networks.
This initiative marks the first step toward the vision proposed in the Science Council of Japan’s Future Academic Advancement Initiative (2023), contributing directly to Kyushu University VISION 2030: driving social change with integrative knowledge.
A Kickoff Symposium on December 25 will discuss the institute’s future prospects.
###
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.
UMass researchers help ID new mineral on Mars, providing insight on the Red Planet’s potential to have supported life
Identifying the mineral on Mars’ surface has eluded scientists for decades
AMHERST, Mass. — Researchers from the University of Massachusetts Amherst are part of a team that has identified a unique mineral on Mars, described in Nature Communications. Named ferric hydroxysulfate, the mineral provides clues about the Martian environment and history of the planet, including the possibility of former lava, ash or hydrothermal activity.
Mars gets its trademark red hue from the abundance of iron on its surface, but that’s just what can be seen with the naked eye. The various minerals on the Red Planet emit unique signatures of light measurable through spectroscopy. Sulfur is particularly abundant and combines with different elements to make sulfate minerals, each with its own spectral signature that can be captured by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), an instrument orbiting the planet.
In 2010, an unusual spectral band was discovered at Aram Chaos, a heavily eroded impact crater, and the plateau above Juventae Chasma, a large canyonlike depression. Identifying the mineral that exhibits this particular spectral signature has eluded researchers because its unique shape and location is not consistent with any known mineral.
To identify the material, scientists needed more data. “The data that comes out of the spectrometer is not usable the way it is,” explains Mario Parente, associate professor of electrical and computer engineering at UMass Amherst and one of the authors of the paper. “We have to calibrate the data, correct the data, remove the effect of the atmosphere,” he says, highlighting that the light—which travels from the sun to the mineral to CRISM—has to go through the Martian atmosphere twice.
“There are scattering molecules and gases that absorb light in the atmosphere,” he says. “For example, on Mars, there is an abundance of carbon dioxide, and that will distort the data.” Parente has the most advanced atmospheric correction algorithm tailored to Mars. Using deep learning artificial intelligence approaches, his team can map the known and unknown minerals, automatically recognizing anomalies in the individual pixels of an image. Notably, Parente produced detailed maps of the Jezero Crater, landing site of the Perseverance rover because it is believed to have once contained water.
Using these methods, Parente and his team revealed additional locations on the planet with the same spectral band and clarified additional spectral features. From these newly refined characteristics, researchers at the SETI Institute and NASA Ames Research Center were able to reproduce the mineral in the lab and determined the mystery compound as ferric hydroxysulfate.
“The material formed in these lab experiments is likely a new mineral due to its unique crystal structure and thermal stability,” lead author Janice Bishop, senior research scientist at the SETI Institute and NASA Ames Research Center said in a statement. “However, scientists must also find it on Earth to officially recognize it as a new mineral.”
Ferric hydroxysulfate forms at high temperatures (50° to 100° C) in an acidic environment and in the presence of oxygen and water. “Once you make a mineral attribution and you have good indications of a certain material, then you can start thinking about: When does this material occur? In what condition does it form?” says Parente.
The researchers concluded that ferric hydroxysulfate was formed at Aram Chaos via geothermal heat, while the same mineral was formed at Juventae through volcanic heating by ash or lava. They speculate that this likely happened during the Amazonian period, less than 3 billion years ago.
“Temperature, pressure and conditions such as pH are all very important indications of what the paleoclimate was,” says Parente. He is excited about the new level of detail scientists have for understanding the Red Planet through this research. “The presence of this mineral puts a lot more nuance on what was going on. Parts of Mars have been chemically and thermally active more recently than we once believed—offering new insight into the planet's dynamic surface and its potential to have supported life.”
Journal
Nature Communications
Method of Research
Imaging analysis
Subject of Research
Not applicable
Article Title
Characterization of ferric hydroxysulfate on Mars and implications of the geochemical environment supporting its formation
Cross-validation method enhances atmospheric corrections in satellite positioning
Aerospace Information Research Institute, Chinese Academy of Sciences
image:
Design of quality monitoring for grid-base atmospheric corrections.
view moreCredit: The authors
Accurate positioning is vital for applications ranging from autonomous vehicles to precision agriculture, yet atmospheric disturbances often compromise Global Navigation Satellite System (GNSS) performance. This study introduces a novel method that applies leave-one-out cross-validation to monitor the quality of atmospheric corrections in Precise Point Positioning–Real-Time Kinematic (PPP-RTK) services. By using each station sequentially as a validation point, the method produces real-time quality information without requiring extra monitoring stations or historical datasets. Experiments in both large-scale European and small-scale Hong Kong networks show that this approach can capture centimeter-level variations in atmospheric conditions and improve positioning accuracy by more than 20%, even under strong solar activity.
Precise Point Positioning (PPP) has become indispensable in delivering high-precision Global Navigation Satellite System (GNSS) results, but its relatively long convergence time limits real-time applications. To address this, Precise Point Positioning–Real-Time Kinematic (PPP-RTK) leverages atmospheric corrections to accelerate ambiguity resolution. However, the accuracy of these corrections is highly sensitive to factors like satellite elevation, solar activity, and station spacing, leading to errors that range from centimeters to decimeters. Traditional solutions either rely on empirical models built from historical data or require dense monitoring networks, both of which limit adaptability. Due to these challenges, there is a pressing need to develop robust, real-time quality monitoring methods for atmospheric corrections.
Researchers from Wuhan University and Universitat Politècnica de Catalunya have unveiled a new strategy to enhance GNSS PPP-RTK performance. Published (DOI: 10.1186/s43020-025-00178-5) on September 22, 2025 in Satellite Navigation, the study presents a leave-one-out cross-validation technique to evaluate and improve atmospheric correction accuracy. By systematically designating each station as a validation point, the method produces dynamic quality information that is broadcast alongside corrections. This innovative approach provides users with self-monitoring atmospheric data, significantly improving positioning stability and reliability, particularly under variable or disturbed atmospheric conditions.
The new approach fundamentally rethinks how atmospheric corrections are validated. Instead of relying on external monitoring stations or static models, the leave-one-out cross-validation technique internally rotates each reference station as a "test case" while others generate correction data. The resulting discrepancies reveal the true quality of atmospheric corrections, which are then compiled into a comprehensive quality map. This information is transmitted directly to users, allowing them to assess reliability in real time.
Experiments were conducted in two distinct networks: a 21-station European system in mid-latitudes, generally stable, and a 19-station Hong Kong network in low latitudes, prone to ionospheric disturbances. Results showed that tropospheric corrections maintained stability within 2 cm, while ionospheric variations ranged from 2 to 15 cm depending on solar activity. Importantly, the method consistently provided reliable envelopes of error estimates, with more than 90% of quality values accurately reflecting real deviations. In PPP-RTK positioning trials, the method improved accuracy by 6–29% in Europe and 9–20% in Hong Kong, while also achieving faster convergence. Even during geomagnetic storms, improvements of up to 40% were recorded. These findings underscore the method's robustness across scales and atmospheric conditions.
"Our work demonstrates that GNSS services can become more resilient by embedding self-monitoring capabilities," said Prof. Xingxing Li, corresponding author of the study. "The leave-one-out cross-validation approach eliminates the dependence on additional monitoring stations or empirical historical models, offering flexibility across diverse networks. Most importantly, the method ensures that users receive not just corrections, but also a measure of their reliability. This is critical for safety-sensitive applications like autonomous driving and disaster response, where accuracy under unpredictable atmospheric conditions cannot be compromised."
The ability to broadcast real-time quality information alongside atmospheric corrections marks a significant step toward more trustworthy GNSS positioning. By ensuring centimeter-level accuracy across different regions and atmospheric conditions, the method has immediate potential in fields requiring dependable navigation, such as intelligent transportation systems, precision farming, and surveying. Moreover, during periods of high solar activity or geomagnetic storms, the approach can maintain stability and reduce positioning errors, safeguarding operations that rely on continuous precision. Looking forward, integrating this method into global augmentation services could accelerate the adoption of GNSS-based solutions for both civilian and industrial applications.
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References
DOI
Original Source URL
https://doi.org/10.1186/s43020-025-00178-5
Funding information
This study is financially supported by the National Natural Science Foundation of China (No. 42425401, 42474023, 42204017), the Hubei Provincial Natural Science Foundation Exploration Program (2024040801020242), the Fundamental Research Funds for the Central Universities (2042024kf0018), and the Major Program of Hubei Province (2023BAA02). The work of Junjie Han is supported by the China Scholarship Council under Grant 202406270020.
About Satellite Navigation
Satellite Navigation (E-ISSN: 2662-1363; ISSN: 2662-9291) is the official journal of Aerospace Information Research Institute, Chinese Academy of Sciences. The journal aims to report innovative ideas, new results or progress on the theoretical techniques and applications of satellite navigation. The journal welcomes original articles, reviews and commentaries.
Journal
Satellite Navigation
Subject of Research
Not applicable
Article Title
Quality monitoring of grid-based atmospheric corrections in GNSS PPP-RTK service using leave-one-out cross-validation
Article Publication Date
22-Sep-2025
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