SPACE/COSMOS
Where did cosmic rays come from? MSU astrophysicists are closer to finding out
image:
X-ray image of the newly discovered pulsar wind nebular associated with an extreme Galactic cosmic ray source 1LHAASO J0343+5254u, obtained by the XMM-Newton space telescope (DiKerby, Zhang, et al., ApJ, 983, 21)
view moreCredit: XMM-Newton space telescope
EAST LANSING, Mich. – New research published by Michigan State University astrophysicists could help scientists answer a century-old question: where did galactic cosmic rays come from?
Cosmic rays – high-energy particles moving close to the speed of light – originated from somewhere in the Milky Way galaxy and beyond, but exactly where has been a mystery since they were discovered in 1912. Shuo Zhang, MSU assistant professor of physics and astronomy, and her group led two studies that shed new light on where cosmic rays might have come from. The recently published findings were presented this week at the 246th meeting of the American Astronomical Society in Anchorage, Alaska.
The sources of these high-energy, fast-moving particles could bear the nature of black holes, supernova remnants and star forming regions. These extreme astrophysical events are also known to produce neutrinos – tiny, nearly massless particles that are found in abundance not only deep in space, but also on our planet.
“Cosmic rays are a lot more relevant to life on Earth than you might think,” Zhang said. “About 100 trillion cosmic neutrinos from far, far away sources like black holes pass through your body every second. Don’t you want to know where they came from?”
Cosmic ray sources are so powerful that they can accelerate a proton or electron into energies far beyond what humans are able to do with the most advanced particle accelerator. Zhang’s group is studying these cosmic particle accelerators, known as PeVatrons, to find out where and what they are, and how they’re able to accelerate small particles into extremely high energies. Understanding more about them can help unlock fundamental questions in physics, such as galaxy evolution and the nature of dark matter.
Her group’s latest papers explore multi-wavelength studies of PeVatron candidates whose sources remained unknown. In the first paper, Stephen DiKerby, a postdoctoral student in Zhang’s group, investigated a mysterious PeVatron candidate discovered by the Large High Altitude Air Shower Observatory (LHAASO), but the nature of the source was still unknown. Using X-ray data from the XMM-Newton space telescope, DiKerby found a pulsar wind nebula – an expanding bubble with relativistic electrons and positions with energy injection from a pulsar. This finding established this PeVatron as a pulsar wind nebula type of cosmic ray source and is one of a few cases where scientists can identify the nature of PeVatrons.
In the second paper, three MSU undergraduate students in Zhang’s group – Ella Were, Amiri Walker and Shaan Karim – used NASA’s Swift X-ray telescope to observe X-ray emissions from little-explored LHAASO cosmic ray sources. The team calculated the upper limits for the X-ray emission, and their work could serve as a pathfinder for future studies.
“Through identifying and classifying cosmic ray sources, our effort can hopefully provide a comprehensive catalogue of cosmic ray sources with classification,” Zhang said. “That could serve as a legacy for future neutrino observatory and traditional telescopes to perform more in-depth study in particle acceleration mechanisms.”
Next, Zhang’s team plans to tackle another study on cosmic ray sources by combining data it collects from the IceCube Neutrino Observatory with those from X-ray and gamma-ray telescopes. They want to explore why some cosmic ray sources emit neutrinos but not others, as well as where and how the neutrinos are produced.
“This work will call for collaboration between particle physicists and astronomers,” Zhang said. “It’s an ideal project for the MSU high-energy physics group.”
This work is supported by multiple NASA observation grants and the National Science Foundation IceCube analysis grant.
By Bethany Mauger
Journal
The Astrophysical Journal
Article Title
Discovery of a Pulsar Wind Nebula Candidate Associated with the Galactic PeVatron 1LHAASO J0343+5254u
Space storm captured by NRL spurs new era in CME research
Naval Research Laboratory
video:
Images from NOAA’s CCOR-1 coronagraph showing the ‘halo’ coronal mass ejection on May 31, 2025. Launched last year, and designed and built by NRL, the CCOR-1 coronagraph is the first operational coronagraph providing critical real-time observations for NOAA to issue space weather forecasts and storm alerts.
view moreCredit: NOAA's CCOR-1
WASHINGTON, D.C. — Local weather alerts are familiar warnings for potentially dangerous conditions, but an alert that puts all of Earth on warning is rare.
On May 31, U.S. Naval Research Laboratory’s (NRL) space-based instrumentation captured real-time observations of a powerful Coronal Mass Ejection (CME) that erupted from the Sun initiating a “severe geomagnetic storm” alert for Earth.
"Our observations demonstrated that the eruption was a so-called ‘halo CME,’ meaning it was Earth-directed, with our preliminary analysis of the data showing an apparent velocity of over 1,700 kilometers per second for the event," stated Karl Battams, Ph.D., computational scientist for NRL’s Heliospheric Science Division.
A geomagnetic storm is a major disturbance of Earth's magnetosphere that’s caused by the highly efficient transfer of energy from the solar wind into our planet's surrounding space environment. These disruptions are primarily driven by sustained periods of high-speed solar wind and, crucially, a southward-directed solar wind magnetic field that can peel away Earth’s field on the dayside of the magnetosphere. Energy from the solar wind can open Earth's magnetic shield.
The National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Center classified the recent solar storm as G4, the second-highest classification on its five-level geomagnetic scale.
Powerful storms such as this are typically associated with CMEs. The repercussions can range from temporary outages and data corruption to permanent damage to satellites, increased atmospheric drag on low-Earth orbit spacecraft altering their trajectories, and disruptions to high-frequency radio communications.
“Such disturbances can compromise situational awareness, hinder command and control, affect precision-guided systems, and even impact the electrical power grid, directly affecting military readiness and operational effectiveness,” Battams said.
CMEs are colossal expulsions of plasma and magnetic field from the Sun's corona, often carrying billions of tons of material. While CMEs generally take several days to reach Earth, the most intense events have been observed to arrive in as little as 18 hours.
"CMEs are the explosive release of mass from the Sun’s low corona and are a primary driver of space weather, playing a central role in understanding the conditions of the Earth’s magnetosphere, ionosphere, and thermosphere," explained Arnaud Thernisien, Ph.D., a research physicist from the Advanced Sensor Technology Section within NRL's Space Science Division.
The May 30 event saw a relatively slow but powerful solar flare erupt from the Earth-facing side of the Sun. The energy released blasted a CME directly toward Earth, leading to the geomagnetic storm that has produced auroras as far south as New Mexico.
NRL's space-based instrumentation, operating on NASA and NOAA spacecraft, provided vital real-time observations of this event. Notably, NRL's venerable Large Angle Spectrometric Coronagraph (LASCO), which has been in operation since 1996, and the Compact Coronagraph 1 (CCOR-1), launched in 2024, both relayed critical data.
Such observations are paramount for operational space weather monitoring, allowing forecasters to predict the timing of the event's arrival at Earth and the potential geomagnetic storm it could induce. While precisely predicting the severity, exact timing, or duration of a geomagnetic storm remains challenging, these advance warnings are vital for enabling the Department of Defense (DoD) and other agencies to prepare.
The potential impacts of severe geomagnetic storms on DoD and Department of the Navy missions are significant and far-reaching. These events can disrupt or degrade critical systems and capabilities, including satellite communications, Global Positioning System (GPS) navigation and timing, and various remote sensing systems.
“NRL has been a pioneer in heliophysics and space weather research since the very inception of the field, dating back to the first discovery of CMEs through NRL space-based observations in 1971,” Battams said. “Since then, NRL has consistently maintained its position at the forefront of coronal imaging with a portfolio of groundbreaking instrumentation that has driven heliospheric and space weather studies.”
This includes:
- LASCO coronagraphs operating on the joint ESA-NASA Solar and Heliospheric Observatory (SOHO) mission since 1996
- Sun-Earth Connection Coronal and Heliospheric Investigation (SECCHI) instrument packages on the twin NASA Solar Terrestrial Relations Observatory (STEREO) spacecraft since 2006
- Wide-Field Imager for Parker Solar Probe (WISPR) instrument on NASA Parker Solar Probe (PSP) since 2018
- Solar Orbiter Heliospheric Imager (SoloHI) on ESA’s Solar Orbiter mission since 2019
- NOAA’s CCOR-1, designed and built by NRL, operating on NOAA’s GOES-19 since 2024
These assets, particularly instruments like LASCO and CCOR-1, are indispensable for providing the crucial real-time imagery necessary for forecasters to analyze and assess CMEs, determine Earth-impact likelihood, and issue timely warnings.
“They form the backbone of our ability to anticipate and mitigate the effects of space weather. As the G4 severe geomagnetic storm watch continues, the public and critical infrastructure operators are encouraged to visit NOAA’s Space Weather Prediction Center for the latest information and updates,” Thernisien said.
The journey of the CME, from its fierce eruption on the Sun to its arrival at Earth, approximately one million miles away, highlights the dynamic nature of our solar system and the ongoing importance of NRL's vital contributions to heliophysics research and space weather preparedness. The data collected from events such as this will be instrumental in future research, further enhancing our understanding and predictive capabilities and ultimately bolstering the resilience of national security and critical infrastructure.
To keep up to date on space weather, visit NOAA’ Space Weather Prediction Center.
About the U.S. Naval Research Laboratory
NRL is a scientific and engineering command dedicated to research that drives innovative advances for the U.S. Navy and Marine Corps from the seafloor to space and in the information domain. NRL, located in Washington, D.C. with major field sites in Stennis Space Center, Mississippi; Key West, Florida; Monterey, California, and employs approximately 3,000 civilian scientists, engineers and support personnel.
For more information, contact NRL Corporate Communications at (202) 480-3746 or nrlpao@us.navy.mil. Please reference package number at top of press release.
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Researchers discover likely site of new planet in formation
image:
Image of the young nearby 2MASS1612 system (also known as: RIK113) taken with the ESO Very Large Telescope in Chile. The image uses near infrared light that was scattered of the dust particles surrounding this young star. While the disk itself is enormous in size (larger than the solar system), it appears tiny on sky (roughly the size of a pinte glass in Galway as seen from Tuam) due to its huge distance of 430 light years from Earth. The structures in the disk indicate that a young gas giant planet is forming in the system. Credit - ESO/C. Ginski et al
view moreCredit: Credit - ESO/C. Ginski et al
Monday June 9, 2025: An international team of astronomers led by University of Galway, has discovered the likely site of a new planet in formation, most likely a gas giant planet up to a few times the mass of Jupiter.
Using the European Southern Observatory's Very Large Telescope (ESO’s VLT) in Chile, the researchers captured spectacular images around a distant young star for the first time in the form of scattered near-infrared light that revealed an exceptionally structured disk.
The European Southern Observatory (ESO), the world’s foremost international astronomy organisation, has today (Monday June 9, 2025) published a stunning view of the new planet-forming disk as their picture of the week.
The disk extends out to 130 astronomical units from its parent star - the equivalent to 130 times the distance between Earth and the Sun. It shows a bright ring followed by a gap centered at roughly 50 astronomical units.
For comparison, the outermost planet in our solar system, Neptune, has an orbital distance from the Sun of 30 astronomical units.
Inside the disk gap, reminiscent of the outskirts of a hurricane on Earth, a system of spiral arms are visible. While appearing tiny in the image, the inner part of this planet-forming system measures 40 astronomical units in radius and would swallow all of the planets in our own solar system.
The study was led by Dr Christian Ginski from the Centre for Astronomy in the School of Natural Sciences at University of Galway and was co-authored by four postgraduate students at the University.
Dr Christian Ginski, lecturer at the School of Natural Sciences, University of Galway and lead author of the paper, said: “While our team has now observed close to 100 possible planet-forming disks around nearby stars, this image is something special. One rarely finds a system with both rings and spiral arms in a configuration that almost perfectly fits the predictions of how a forming planet is supposed to shape its parent disk according to theoretical models. Detections like this bring us one step closer to understand how planets form in general and how our solar system might have formed in the distant past.”
The study has been published in the international journal Astronomy and Astrophysics.
Dr Ginski said: “Besides this exceptionally beautiful planet-forming cradle there is something else that I find quite special about this study. Along with the large international team that we assembled for these observations, four of our own University of Galway graduate students were involved in this study. Without the critical help of Chloe Lawlor, Jake Byrne, Dan McLachlan and Matthew Murphy we would not have been able to finalise the analysis of these new results. It is my great privilege to work with such talented young researchers.”
Chloe Lawlor, PhD student in Physics with a specialisation in Astrophysics, University of Galway, said: “Working with Dr Christian Ginski on the 2MASS1612 paper has been an incredible experience. As an early-career researcher, having the opportunity to contribute to such exciting work has been especially rewarding. This work has been the perfect introduction to scientific writing and collaboration, and I’m very grateful for this kick-start to my research career.”
Jake Byrne, MSc student in Physics with a specialisation in Astrophysics, University of Galway, said: “It’s an exciting time to be involved in planet formation theory at the University of Galway. There was a strong sense of collaboration among everyone involved in this paper, and I’m grateful to have been part of it. It's been a great introduction into what I hope to be a long career in research.”
Dan McLachlan, MSc student in Physics with a specialisation in Astrophysics, University of Galway, said: “I found it quite a thrilling experience to be making my first contribution to an astrophysics publication and was very grateful for the opportunity provided by being a part of Dr Ginski's research group. I also honed my academic writing skills in stepping up to the challenge and learned a few analytical techniques that will be of vital use in my own future research work.”
The wider research team included colleagues in the UK, Germany, Australia, USA, Netherlands, Italy, Chile, France, Japan.
The scientific paper speculates on the presence of a planet based on its structure and the rings and spirals observed in the disk. It also notes some tentative atmospheric emission of just such a planet which the research team say requires further study to confirm.
Based on their research findings, Dr Ginski and his team have secured time at the world leading James Webb Space Telescope (JWST) observatory in the upcoming observation cycle.
Using the unprecedented sensitivity of the James Webb Telescope, the team hopes to be able to take an actual image of the young planet. If planets in the disk are confirmed, it will become a prime laboratory for the study of planet-disk interaction.
The full study can be read here: https://doi.org/10.1051/0004-6361/202451647
See the ESO photo of the disk here: https://www.eso.org/public/images/potw2523a/
Ends
Media queries to pressoffice@universityofgalway.ie
Notes for Editors
About The James Webb Telescope
The James Webb Telescope studies every phase in the history of our Universe, ranging from the first luminous glows after the Big Bang, to the formation of solar systems capable of supporting life on planets like Earth, to the evolution of our own Solar System. It does not orbit around the Earth like the Hubble Space Telescope, it orbits the Sun 1.5 million kilometers (1 million miles) away from the Earth.
About University of Galway
Established in 1845, University of Galway is one of the top 2% of universities in the world. We are a bilingual university, comprised of four colleges, 18 schools and five research institutes, with more than 19,000 students, including around 3,000 international students. We have been accredited with an Athena SWAN Institutional Bronze Award, and 12 out of our 18 schools hold individual Athena SWAN Awards. We have more than 2,500 staff, and research collaborations with 4,675 international institutions in 137 countries. We have 133,000 alumni and 98% of graduates are in employment or further study within six months.
For more information visit https://www.universityofgalway.ie/ or view all news
Get the most from the expert commentary, views and stories from University of Galway on our Cois Coiribe platform https://impact.universityofgalway.ie/
Simulation of the disk in the 2MASS1612 system. [VIDEO] |
Simulation of the disk in the 2MASS1612 system. The planet is seen as a bright dot in the simulation that circles the central star within the gap of the disk. The planet drives the spiral arms seen in the disk center. The team of astronomers at the University of Galway will use the James Webb Space Telescope to attempt to take an image of this planet. Credit: C. Pinte/ C. Ginski et al.
Credit
ESO/C. Ginski et al
Journal
Astronomy and Astrophysics
Method of Research
Observational study
Subject of Research
Not applicable
Article Title
Disk Evolution Study Through Imaging of Nearby Young Stars (DESTINYS): Evidence of planet-disk interaction in the 2MASSJ16120668-3010270 system
Article Publication Date
9-Jun-2025
New SwRI model explains exoplanetary systems with compact orbits
New model accounts for the remarkably consistent total mass of planets relative to host star’s mass
image:
Southwest Research Institute scientists propose a new model for the formation of compact exoplanetary systems that contain multiple rocky planets in tight orbits around their star. In this model, planets begin to form in regions of a disk around a young star that are fed by an ongoing infall of gas and small grains. Growing planets collect rocky material while gradually spiraling inward through interactions with surrounding gas. As a planet gains mass, its inward migration accelerates. This process yields a compact planetary system with a planets-to-star mass ratio consistent with observed compact exoplanetary systems.
view moreCredit: Southwest Research Institute
SAN ANTONIO — June 9, 2025 — Star and planet formation has largely been considered separate, sequential processes. But in a new study, scientists at Southwest Research Institute (SwRI) have modeled a different scenario where planets start developing early — during the final stages of stellar formation — rather than after this phase ends, as previously assumed.
Among the many thousands of known exoplanets there is a large population of compact systems that each have multiple planets orbiting very close to their central star. This contrasts with our solar system, which lacks planets orbiting closer than Mercury. Interestingly, in compact systems, the total mass of the planets in each system relative to the host star’s mass is remarkably consistent across hundreds of systems. The cause of this common mass ratio remains a mystery.
Dr. Raluca Rufu and Dr. Robin Canup of SwRI’s Solar System Science and Exploration Division in Boulder, Colorado, used advanced simulations that show surviving early-formed planets match multiple observed features of compact systems, including both tight planetary orbits and a common mass ratio. Early planet growth also is consistent with prior observations of disks around young stars made by the Atacama Large Millimeter Array (ALMA) telescope.
“Compact systems are one of the great mysteries of exoplanet science,” said Rufu, a Sagan Fellow and lead author of a Nature Communications describing this research. “They contain multiple rocky planets of similar size, like peas-in-a-pod, and a common mass ratio that is very different than that of our solar system’s planets.”
“Intriguingly, the common mass ratio seen in compact exoplanetary systems is similar to that of the satellite systems of our gas planets. These moons are thought to have developed as gas planets finalized their formation. This seems a powerful clue that compact systems may reflect a similar underlying process,” said Canup.
A star forms as a molecular cloud of gas and dust collapses due to its own gravity. As material from the cloud infalls towards the central star, it is first deposited into a circumstellar disk orbiting the star. After infall ends, the disk persists for a few million years before its gas disperses. Planets form within the disk, starting with collisions and accumulation among dust grains and ending with the gravitational assembly of planets.
“Conventionally, it has been assumed that planetary assembly started after stellar infall ended. However, recent ALMA observations provide strong evidence that planetary accretion, or formation, may begin earlier,” said Rufu. “We propose that compact systems are surviving remnants of planet accretion that occurred during the final phases of infall.”
The new numerical simulations show that during infall, growing planets collect rocky material while their orbits gradually spiral inward through interactions with surrounding disk gas. As a planet gains mass, its inward orbit migration accelerates, so that planets above a critical mass fall into the star and are consumed. This balance between planetary growth and loss tends to produce similarly sized planets with characteristic masses determined by infall and disk conditions.
“We find that planets that accrete during infall can survive until the gas disk disperses and orbital migration ends,” said Canup. “Importantly, across a broad range of conditions, the mass of surviving systems is proportional to the mass of the host star, providing the first explanation for the similar mass ratios of observed multi-planet compact systems.”
The envisioned process is similar to the way moons may form around giant planets like Jupiter. Moons grow within a disk surrounding the planet that is fed by infalling gas and dust material from the circumstellar disk. A key difference lies in the timing: moon-forming disks disperse quickly once infall stops, while planet-forming disks around stars can last up to several million years. This subtle difference yields somewhat lower mass ratios for compact planetary systems than for gas planet satellite systems.
“It’s exciting to see that the process of early assembly in young disks may work in a similar way across very different scales,” the team notes.
To read the Nature article titled “Origin of compact exoplanetary systems during disk infall,” see: https://doi.org/10.1038/s41467-025-60017-8.
For more information, visit https://www.swri.org/markets/earth-space/space-research-technology/space-science/planetary-science.
Southwest Research Institute scientists have developed a new model that explains the formation of compact exoplanetary systems, such as TRAPPIST-1, that contain multiple rocky planets in very tight orbits around their star. In contrast, our solar system is much more expansive and has no planets inside the orbit of Mercury.
Credit
NASA/JPL-Caltech
Journal
Nature Communications
Method of Research
Computational simulation/modeling
Subject of Research
Not applicable
Article Title
Origin of compact exoplanetary systems during disk infall
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