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Almost a decade after NASA’s InSight mission put the first working seismometer on the Martian surface, researchers are still combing through its records of faint ground vibrations to reveal secrets of the planet’s deep interior.

In a recent analysis, scientists reported seismic evidence that Mars has a solid inner core, an unexpected finding that challenges earlier studies that suggested the planet’s core was entirely molten.

Like Earth—and onions and ogres—the interior of Mars has layers. These layers have different densities and can be solid or liquid. As seismic waves move through the layers, they are bent or reflected, especially at boundaries where density changes sharply. By analyzing how these waves propagate, scientists can trace their paths and infer the structure and properties of the materials they pass through.

Previous analyses of InSight data had already mapped the structure of the Martian crust and mantle and also revealed that the planet has a surprisingly large molten metallic core, spanning nearly half its radius. Such a large core, combined with measurements of the planet’s relatively low density, suggested that it must contain a lot of light elements such as sulfur, carbon, hydrogen, and oxygen. These light elements lower iron’s melting point, making it less likely to crystallize to form a solid inner core, which partly explains why the new finding caught InSight scientists off guard.

“None of us really believed that you would have a solid inner core,” said Amir Khan, a geophysicist at ETH Zurich who is part of the InSight science team but wasn’t involved in the new study.

A Long Way to the Core

Still, seismologist Daoyuan Sun of the University of Science and Technology of China in Hefei and his colleagues decided to look for signs of a solid core in the publicly available InSight data. Specifically, they reexamined data from a set of 23 marsquakes with seismic waves that passed through the planet’s core before returning to the surface.

To enhance the faint signals from the seismometer, the team combined—or stacked—recordings from these quakes. This revealed two types of compressional (P) waves that crossed the core. One set, known as P′P′ waves, traveled through the outer core to the farside of the planet, reflected off the surface there, and then passed back through the core to reach the seismometer. The other set, called PKKP waves, passed through the outer and inner core before being reflected back to the surface and encountering the core-mantle boundary on the way out.

“To me that’s the most exciting thing. That’s basically saying that you see this inner core structure. ”

Initially, the researchers could not find the PKKP waves at their expected arrival times. Instead, the waves were arriving 50–200 seconds earlier than predicted if the core was fully molten. The early arrivals suggested the waves had traveled through solid material, which transmits seismic P waves faster than liquids.

While looking for these early-arriving signals, the team also picked up a third set of seismic waves, called PKiKP. These are P waves that reflect back to the surface right at the boundary between the inner and outer core. This is the same type of seismic phase that seismologist Inge Lehmann used to reveal the existence of Earth’s solid inner core in 1936.

Finding these PKiKP waves in InSight data offered scientists a strong clue that Mars, too, may have a solid core.

“To me that’s the most exciting thing,” Sun said. “That’s basically saying that you see this inner core structure.”

By measuring the travel times of the seismic phases, Sun’s team estimated that Mars has a solid inner core with a radius of about 613 kilometers—roughly 18% percent of the radius of the planet itself. That ratio is very similar to that of Earth’s inner core, which is about 19% of Earth’s radius, and much larger than many researchers anticipated Mars could have. The new findings were published in Nature.

The team posited that their seismic observations could be explained by an outer core made up mostly of liquid or molten iron and nickel, as well as smaller amounts of sulfur and oxygen, and no more than 3.8% carbon, encasing a solid inner core enriched in more oxygen.

“It’s like Mars has lifted just the corner of its veil and allowed us to peek inside, but only a sneak peek—we could not get the full picture.”

These levels of light elements remain difficult for scientists to explain, Khan said. As light elements prefer to stay liquid, the existence of a solid inner core means that the outer core around it would have to be even richer in light elements than in previous models, which were already pushing the limits of what seemed plausible. On top of that, the building blocks from which scientists think Mars formed don’t contain enough of these elements to account for the abundance required by a solid core, Khan added.

The finding is also at odds with two studies published 2 years ago, one of them led by Khan, that proposed that a layer of molten rock sits at the bottom of the mantle, just above the core, insulating it like a thermal blanket. Such a layer would keep the core hotter, making it more difficult for it to crystallize and solidify.

“It’s like Mars has lifted just the corner of its veil and allowed us to peek inside, but only a sneak peek—we could not get the full picture,” Khan said. “We are not there yet.”

A Hibernating Dynamo

The new finding also renews questions about the absence of a global magnetic field on Mars. Earth’s magnetic field is sustained by the slow crystallization of the core, which drives magnetism-inducing convective motions in the liquid outer core. We know that Mars once had a magnetic field, but it died out billions of years ago.

If Mars does have a solid inner core, why is its magnetic dynamo inactive?

The likely reason is that core crystallization, and thus convection in the outer core, is too slow to power a global magnetic field on Mars, said Douglas Hemingway, a planetary scientist at the University of Texas at Austin and a coauthor of the new study. Mars’s early magnetic field was likely powered by primordial heat escaping from its core. As the planet cooled over billions of years, this convection weakened, and the magnetic field eventually disappeared.

Finding a solid core on Mars, however, opens up the intriguing possibility of a global magnetic field eventually reigniting, Hemingway said. The process of crystallization happens at the boundary of the outer core and the inner core, and if this surface grows larger over time, it could reach a point where there’s enough convective motion to kick-start the dynamo and revive the global magnetic field.

In earlier work, Hemingway predicted that if the Martian core is crystallizing from the center outward, the magnetic field could turn on sometime within the next billion years. “So, you know, if we wait a billion years and it doesn’t happen, then we were wrong,” he joked.

There may be no definitive confirmation of the existence of a solid core on Mars for a long time. The InSight mission ended in 2022, after dust piling up on the lander’s solar panels drained the device’s power supply, and new seismic data from Mars won’t be available for decades, most likely.

“Maybe when we send humans, we would be motivated to bring a few seismometers,” Hemingway said.

—Javier Barbuzano (@javibar.bsky.social), Science Writer

Citation: Barbuzano, J. (2025), Scientists may have finally detected a solid inner core on Mars, Eos, 106, https://doi.org/10.1029/2025EO250367. Published on 1 October 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

SummaryFlooding of abandoned excavation mines implies significant changes in the hydromechanic rock behavior often associated with instantaneous rock instabilities which cause underground and ground failure and collapses, sometimes (but not always) accompanied by induced seismicity. The permanent modification of the hydrogeological setting may, in certain cases, also induce long-term seismic activities persistent over several years. The governing hydromechanic triggering mechanisms are poorly understood in these cases what bares challenges in related seismic hazard and risk assessment. In this study, we provide new insights into this poorly explored field of fluid induced seismicity, by investigating the long-lasting (> 10 years) swarm activity induced by the flooding of an abandoned coal mine at Gardanne in Southern France. The strongest events of the activity have comparatively small magnitudes (Mw < 2) but are felt by the local population due to their shallow source depth (< 1 km). Thanks to full waveform based source analysis we show that the swarm is associated with the permanent activation of preexisting faults situated below the flooded mining voids which act as a very high-capacity anthropogenic reservoir and aquifer. We further show that mine water level changes caused by either natural or anthropogenic driving forces cause seismic triggering which involves direct pore-pressure as well as poroelastic effects. These findings provide constraints for adequate guidelines for safe mine water level management and seismic risk mitigation.

SummaryHigh-resolution seismic reflections are essential for imaging and monitoring applications. In seismic land surveys using sources and receivers at the surface, surface waves often dominate, masking the reflections. In this study, we demonstrate the efficacy of a two-step procedure to suppress surface waves in an active-source reflection seismic dataset. First, we apply seismic interferometry (SI) by cross-correlation, turning receivers into virtual sources to estimate the dominant surface waves. Then, we perform adaptive subtraction to minimise the difference between the surface waves in the original data and the result of SI. We propose a new approach where the initial suppression results are used for further iterations, followed by adaptive subtraction. This technique aims to enhance the efficacy of data-driven surface-wave suppression through an iterative process. We use a 2D seismic reflection dataset from Scheemda, situated in the Groningen province of the Netherlands, to illustrate the technique’s efficiency. A comparison between the data after recursive interferometric surface-wave suppression and the original data across time and frequency-wavenumber domains shows significant suppression of the surface waves, enhancing visualization of the reflections for subsequent subsurface imaging and monitoring studies.

Scientists at King Abdullah University of Science and Technology (KAUST) have provided conclusive evidence that the Red Sea completely dried out about 6.2 million years ago, before being suddenly refilled by a catastrophic flood from the Indian Ocean. The findings put a definitive time on a dramatic event that changed the Red Sea.

Long-term weather forecasting is a difficult task, partly because weather systems are inherently chaotic. Though mathematical equations can approximate the underlying physics of weather, tiny inaccuracies that grow exponentially as a model progresses in time limit most physics-based forecasts to 2 weeks or less.

While publicly registered drinking water must meet government standards and regulations, people accessing private groundwater bores and springs supplying 25 or fewer people have no requirements to test their drinking water. Most of these groundwater self-supplies are found in rural areas and are vulnerable to nitrate contamination, leaving communities at risk if left untested.

On the edge of California's Monterey Bay, ecologist Matthew Savoca and a team of volunteers sift through sand and seawater for microplastics, one of the planet's most pervasive forms of pollution.

Air quality in America's largest cities has steadily improved thanks to tighter regulations on key sources of particulate pollution. However, increased heat, wildfire smoke and other emerging global drivers of urban aerosol pollution are now combining to create a new set of challenges for public health officials tasked with protecting millions of people on the East Coast.

In July 2024, a 7.4-magnitude earthquake struck Calama, Chile, damaging buildings and causing power outages. The country has endured violent earthquakes, including the most powerful recorded in history: a 9.5-magnitude "megathrust" event that struck central Chile in 1960, causing a tsunami and killing between 1,000 to 6,000 people. However, the Calama quake was different from the megathrust quakes that are usually associated with the most destructive events in Chile and around the world.

The Earth became darker from 2001 to 2024, meaning it reflects less sunlight, a research team reports in the journal Proceedings of the National Academy of Sciences.

On September 5, 2020, California's Creek Fire grew so severe that it began producing its own weather system. The fire's extreme heat produced an explosive thunderhead that spewed lightning strikes and further fanned the roaring flames, making containment elusive and endangering the lives of firefighters on the ground. These wildfire-born storms have become a growing part of fire seasons across the West, with lasting impacts on air quality, weather, and climate.

Source: Journal of Geophysical Research: Machine Learning and Computation

Long-term weather forecasting is a difficult task, partly because weather systems are inherently chaotic. Though mathematical equations can approximate the underlying physics of weather, tiny inaccuracies that grow exponentially as a model progresses in time limit most physics-based forecasts to 2 weeks or less.

Estimated values called parameters, which are used to represent the effects of specific physical processes, are important ingredients in these equations. Parameters are inferred by physical data and affect model outcomes by, for example, multiplying or giving different weights to measurements of temperatures, winds, or other factors.

In recent years, artificial intelligence (AI)–based models such as GraphCast and FourCastNet have transformed weather prediction with their ability to learn from large amounts of weather data and produce highly accurate predictions of future weather. However, AI-based models typically contain tens of millions to hundreds of millions of parameters that do not directly translate to underlying physical processes. Because these parameters are not interpretable by researchers, such AI models make only limited contributions to the scientific understanding of weather.

Minor et al. address this limitation by demonstrating the capabilities of a Weak form Scientific Machine Learning (WSciML) algorithm known as Weak form Sparse Identification of Nonlinear Dynamics (WSINDy). Like other AI methods, WSINDy learns from data. But instead of using a highly parameterized approach, it discovers mathematical equations that represent complex, real-world physical processes, such as how air pressure, density, and vorticity interact to determine wind speed and direction.

The researchers applied WSINDy to both simulated and real-world turbulent atmospheric fluid data, which include measurements of temperature, pressure, and wind speed. WSINDy used the artificial data to identify the known equations from the simulation. Most important, WSINDy was also able to successfully identify the governing equations of the known atmospheric physics from a global-scale set of assimilated data incorporating real-world weather observations.

These findings suggest that WSINDy could not only aid in weather forecasting but also help uncover new physical insights about weather, the researchers say. They also note that WSINDy is especially well suited for application to data with high levels of observational noise.

However, further work will be needed to refine WSINDy so it can identify more accurately certain kinds of known atmospheric equations, such as realistic models for atmospheric wind, the researchers say. The algorithm is also being explored for use across a wide range of other scientific areas, including unexplained phenomena in fusion, population behaviors driving epidemics, and communication between cells that leads to collective motion in wound healing. (Journal of Geophysical Research: Machine Learning and Computation, https://doi.org/10.1029/2025JH000602, 2025)

—Sarah Stanley, Science Writer

Citation: Stanley, S. (2025), Unveiling what’s under the hood in AI weather models, Eos, 106, https://doi.org/10.1029/2025EO250365. Published on 30 September 2025. Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Our planet’s tectonic plates have been grinding against and diving below one another since time immemorial. However, the earthquakes that result from all the geological jostling have been actively monitored for less than 2 millennia. Researchers have now proposed how liquefaction features known as sand dikes can be used to both pinpoint and precisely date ancient earthquakes. The team published their findings in Earth and Planetary Science Letters.

The Calling Card of Liquefaction

One of the relatively little known dangers of earthquakes is liquefaction, in which strong shaking causes water-rich sediments to lose their structural integrity and behave almost like a liquid. When the ground is no longer solid, the results can be catastrophic—buildings can tilt substantially or even sink, and buried infrastructure like pipes can rise to the surface.

Liquefaction is therefore one fingerprint of a strong earthquake. And fortunately for researchers hoping to better understand past earthquakes, liquefaction leaves behind a calling card: sand dikes. These subsurface intrusions of fine-grained sediments resemble upward-pointing icicles. Sand dikes form in a matter of seconds when mixtures of sand and water are squeezed into cracks opened by ground shaking and the water later drains away. “They give undisputed evidence that an earthquake has occurred,” said Devender Kumar, a scientist at the National Geophysical Research Institute, a research laboratory of the Council of Scientific and Industrial Research, in Hyderabad, India.

Determining when a sand dike formed would therefore reveal when its parent earthquake occurred. And understanding such timing has long been a research goal, said Kumar. “That’s the most important question we need to answer in paleoseismology.”

“This is the million-dollar question.”

To get a handle on the timing of ancient earthquakes, previous studies turned to radiocarbon dating of organic matter found near sand dikes. But that technique comes with its own uncertainties, said Ashok Kumar Singhvi, a geoscientist at the Physical Research Laboratory in Navrangpura, India, and Shantou University in Shantou, China. It’s impossible to know whether the organic material was laid down contemporaneously with the sand dike and therefore the earthquake, said Singhvi. “This is the million-dollar question.”

Younger, but Why?

Another technique, known as optically stimulated luminescence, can be used to date sand dike sediments directly. This method relies on measuring the energy stored up over time in quartz grains from the natural radioactive decay of elements like thorium, uranium, and potassium. Earlier investigations using optically stimulated luminescence showed that sand dike sediments tend to be younger than their host rocks, a tantalizing clue that the luminescence signals in sand dike sediments could be reset, or zeroed out, by an earthquake. But no one had ever conclusively demonstrated this zeroing out effect.

Anil Tyagi, a physicist also at the Physical Research Laboratory, and his colleagues, including Kumar and Singhvi, set out to do just that. Heat, light, and pressure can all reset a material’s luminescence signal, the team knew. But sand dikes form underground, meaning light couldn’t be the culprit, and in sediments that are too soft to generate sufficient pressure, Tyagi and his collaborators concluded. That left heat.

Using a theoretical model developed in the 1970s, the researchers calculated the increase in temperature associated with the formation of a sand dike. Heating occurs simply because of friction, said Kumar: Sediment grains run into each other as they pour upward into a crack in excess of several tens of meters per second. The team estimated that temperatures of up to 450°C were attainable, particularly in the centers of dikes, where sediment grains would be inflowing the fastest.

Tyagi and his colleagues experimentally verified that temperature estimate by analyzing sediment samples taken from five sand dikes in northeastern India. The team calculated that most of the samples had experienced heating to at least 350°C. Such temperatures are sufficient to reset the luminescence signal of quartz grains, earlier work has shown.

“We have a direct method to date sand dikes, and hence past earthquakes.”

These findings demonstrate that quartz grains do indeed zero out their ages when sand dikes form. That fact makes sand dikes valuable and accurate tracers of past ground shaking, said Singhvi. “We have a direct method to date sand dikes, and hence past earthquakes.”

These results are convincing and pave the way for paleoseismological investigations, said Naomi Porat, a luminescence dating scientist who recently retired from the Geological Survey of Israel and who was not involved in the research. In 2007, Porat and her colleagues published a paper that suggested that sand dikes’ luminescence signals were being reset, but the team didn’t posit a mechanism. “We left it as an open question,” said Porat. “It’s so nice to see this paper,” she added. “I waited for 20 years.”

—Katherine Kornei (@KatherineKornei), Science Writer

Citation: Kornei, K. (2025), Spiky sand features can reveal the timing of ancient earthquakes, Eos, 106, https://doi.org/10.1029/2025EO250364. Published on 30 September 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

As global temperatures rise, thermal expansion of oceans and melting ice sheets are driving up sea levels worldwide. In many coastal areas, land subsidence—caused by groundwater extraction and rapid urbanization—further exacerbates flood risks. However, a new study reveals that in China, policy decisions on where and how to develop coastal land may have a more significant impact on future flooding than climate change itself.

In a comment published in Nature Climate Change, Mark Bradford, the E.H. Harriman Professor of Soils and Ecosystem Ecology, and Yale School of the Environment research scientists Sara Kuebbing and Alexander Polussa, Ph.D., together with colleagues Emily Oldfield, Ph.D., of Environmental Defense Fund (EDF) and Jonathan Sanderman of the Woodwell Climate Research Center, argue that the scientific evidence supporting soil carbon's role in mitigating climate change remains too weak to meet the standards required for policy and carbon markets.

Researchers at Georgia Tech have analyzed the seasonal differences of sulfate aerosols—a major pollutant in the United States—to examine the long-term impact from sulfur dioxide (SO₂) emission reductions since the enactment of the Clean Air Act amendments in 1990.

A collaborative research team led by University of Tasmania scientists has returned from a major 54-day voyage on CSIRO research vessel (RV) Investigator to explore the impacts of the devastating 2022 eruption of Tonga's underwater Hunga Volcano.

CubeSats on The Rise

When Devin Phyllides graduates from college next year, she’ll be able to boast something few students can: She’ll have helped launch a satellite into space.

“It’s probably my favorite job I’ve ever had,” she said.

Phyllides, a senior undergraduate physics student at the University of New Hampshire (UNH) in Durham, is a research assistant for the 3UCubed CubeSat project, a collaboration between UNH, Howard University in Washington, D.C., and Sonoma State University in Rohnert Park, Calif.

CubeSats are small satellites first developed in 1999 as a platform for education and space exploration. They are measured in “units” or U, where a 1U CubeSat is a cube measuring 10 centimeters per side. A 2U CubeSat is equivalent to two 1U CubeSats stacked together, a 3U CubeSat is three cubes stacked together, and so on. The NASA-funded 3UCubed satellite is the size of a 1-quart milk carton.

Dozens of people from the three universities have helped design, build, and test the satellite ahead of its planned October 2025 launch, and most of them are university students.

“The goal from the get-go of this CubeSat is to give students hands-on experience, not just in building…but in the full life cycle of a mission,” said Noé Lugaz, a space scientist at UNH and colead of the 3UCubed project.

Students around the world—high schoolers, undergraduates, and graduate students—have participated in CubeSat missions. Student-focused satellite programs not only provide important science in multiple fields but also inspire and engage the next generation of space scientists and engineers.

Why Build a CubeSat?

An entire aerospace industry has been developed around CubeSats, but the tiny satellites also remain a cornerstone of science, technology, engineering, and mathematics (STEM) education for all ages. Today, many of the satellites’ components, such as the chassis, navigation systems, cameras, and scanners, can be purchased off-the-shelf, and most don’t require advanced technical skills to assemble.

Building a CubeSat “still provides the challenge of putting everything together, and making sure the software works, and making sure that it does exactly what needs to be done,” said Floor Bagchus, a master’s student in aerospace engineering and the educational manager for the Da Vinci satellite at Delft University of Technology (TU Delft) in the Netherlands. But because so many of the components come ready to install, “it’s really a very accessible way for engineering students to learn how to make an actual satellite,” she said.

Some CubeSats are space-ready and are launched into orbit or released from the International Space Station. Others are not designed to leave the atmosphere and are lofted by atmospheric balloons for a short time before descending. Their small size and light weight make CubeSats ideally suited for doing science in the upper atmosphere or in low Earth orbit, such as studying Earth’s magnetosphere, atmosphere, and surface conditions.

CubeSats aren’t the only type of small, budget-friendly space mission in the game, Lugaz said, but in his opinion, they offer the most science per dollar and a realistic space mission experience.

In comparison with a CubeSat, “a balloon, for example, would be cheaper, faster, and maybe scientists can do faster turnover and reach more students,” Lugaz said. “A CubeSat is obviously a longer program. But the positive side of this is that the science you can do with a CubeSat is much more [varied and] is also better training for some of the jobs in industry.”

Their size also helps make the idea of space and satellites approachable, especially for younger students, Bagchus said.

“I think people are a bit scared of space, and teachers are scared of space, because they think that space is so gigantic, dark, vast, and complex,” she said. “How can you make sense of such a difficult thing? How can you make students not be so scared of it, and show them that you can actually work in space, do things in space, and overcome very difficult hurdles by very basic principles? I think it’s a very important thing to do in primary schools and high schools to show that you can actually do challenging things.”

Building STEM Pathways for High Schoolers

The simplicity of a CubeSat means that students with limited or no technical experience can learn how to select the satellite components, install the scientific payloads and navigation systems, design the software, and analyze data. In this way, CubeSats can be an entry point into STEM careers.

“I never really thought I’d be able to say that I launched a satellite to space in my high school years.”

In 2022, the Israel Space Agency launched the TEVEL CubeSat constellation, a program designed to provide high school students with a chance to build and launch satellites. Avigail Anidjar learned about the program when she was in eighth grade. When she started at Ulpanat AMIT Givat Shmuel High School near Tel Aviv the following year, she was excited to learn that the school was participating in the program’s second iteration. She joined TEVEL 2 in 2023, at 15 years old.

“I never really thought I’d be able to say that I launched a satellite to space in my high school years,” Anidjar said.

TEVEL 2 gave nine teams of Israeli high school students the opportunity to build and launch a 1U CubeSat. Building a satellite exposes students to an array of STEM fields, including atmospheric science, computer science, engineering, physics, and robotics.

The child of two engineers, Anidjar had taken introductory classes in physics and coding. Still, she learned a lot of hands-on skills in data analysis, computer programming, and problem-solving while working on her school’s CubeSat.

“I’ve always known that I want to go into this kind of field…but now I know that dealing with more space things and satellites is something that’s very interesting, and maybe I want to focus more on that,” she said.

Nine TEVEL 2 satellites, one from each participating school, launched in March 2025 and will operate together to measure the flux of high-energy particles and solar cosmic rays over roughly the next 2 years. The satellites also feature a transponder for ham radio communication.

Anidjar said the launch was “really stressful” but also very rewarding. “We saw our whole work actually come to life. And after a few days, we also got a beacon from it [showing] that it actually works and that it’s alive, and not just a piece of metal in space. It was really exciting.”

Anidjar recently graduated but remains on the satellite’s data analysis team.

Student-built CubeSats can be a tool for educational empowerment, said Maryam Sani, a STEM educator and advocate, and the education lead for the Space Prize Foundation, a U.S.-based nonprofit dedicated to promoting space education and innovation.

In October 2024, Space Prize sponsored the NYC CubeSat challenge, during which 38 high school– and college-age girls and gender minority students from Colombia, Saudi Arabia, the United Kingdom, and the United States spent three intensive days in New York City (NYC) learning what it takes to create a satellite.

The students were split into teams with others they had never met. Some had interest and prior knowledge about space or engineering from school or programs such as Space Camp. Others joined out of curiosity.

“And that was brilliant,” Sani said. “To quote one student, she said, ‘I just thought it would be something nice to do…I can’t believe how much I learned and how much this has made me more interested in finding out about the space industry.’ Which is exactly what we wanted.”

Participants of the 2024 Space Prize NYC CubeSat challenge gather data from their satellites—and pose for photos—while standing on the deck of the museum ship USS Intrepid in New York City. Credit: Space Prize

Throughout the program the students learned basic physics, circuitry, and coding. Each team brainstormed a problem in New York City that a CubeSat could help solve, designed the system, and then built it. Weather prevented the launches, but the participants collected and analyzed data from their creations on the ground.

Sani said that some of the students from Saudi Arabia extended their project after they went home, eventually launching their CubeSat and incorporating the data into an undergraduate project for electrical and computer engineering degrees.

The CubeSat challenge “was a surreal experience,” wrote one participant in her feedback form. “It made me feel more confident that being a woman in STEM was a possibility.”

Space for All

CubeSats can lower the barrier to entry for students around the world who can’t join rocketry programs or other STEM opportunities. CubeSat education programs can foster international participation and collaboration in science, even when pandemic lockdowns prevent in-person meetups.

In 2021, FIRST Global, a U.S.-based nonprofit that promotes international youth STEM education and engagement, hosted a CubeSat Prototype Challenge that enabled students from 176 countries to build and launch CubeSats. Among its initiatives, FIRST Global has organized annual Olympic-style robotics competitions for national youth teams since 2017. The competitions are typically held in-person, but the COVID-19 pandemic prevented the 2021 gathering. Organizers realized that a CubeSat challenge, which they had never done before, could be the answer if it were held remotely.

“We’re trying to connect the world, but we couldn’t do that physically,” said Matt Stalford, the communications director of FIRST Global. “We certainly could do that symbolically, and CubeSats were a huge part of that.”

Each FIRST Global CubeSat challenge team received a standardized CubeSat prototype assembly kit, from which they built their CubeSats. Credit: FIRST Global

For the challenge, each national team—made up mostly of teenagers—defined a mission of importance to their community and designed a CubeSat to collect the data needed to solve it. For example, team Japan studied residual airborne radiation near the Fukushima nuclear site, Team Seychelles collected environmental data to improve local weather forecast accuracy, and Team Argentina studied how local atmospheric conditions obstruct radio transmissions. FIRST Global shipped each team a standardized CubeSat prototype assembly kit.

“Then they had to do the hard part of building it, launching it, taking that data, and writing a report on what that data produced,” Stalford said. Using balloons, the teams launched 90 CubeSats into the lower atmosphere.

Stalford said that asking students to design a satellite that could help solve a problem in their community made the CubeSat challenge more meaningful to them.

“Kids were built to care about the world,” he said. “When you can spark the imagination, when you can get them asking questions like, ‘How can I be part of the solution?’, that’s where kids come alive, and that’s how you spark that love of STEM.”

Reaching Even More Students

FIRSTGlobal’s CubeSat Prototype Challenge inspired the creation of other CubeSat programs, including one run by STEMbees in Accra, Ghana. STEMbees is a nonprofit organization whose mission is to increase the visibility and participation of girls and women in STEM in Ghana and to close the STEM gender gap across Africa.

A STEMbees expert mentored the eight girls from Team Ghana in the 2021 FIRST Global challenge. Team Ghana members built and launched their CubeSat during the challenge and wanted to launch another one after the contest ended. They took their blueprints, customized them with 3D printing, and built a new one. The group went to nearby Academic City University for a launch that attracted the attention of the university students and local community.

“We saw the impact that it created,” said Benedict Amoako, a robotics engineer and STEM instructor with STEMbees. “We had basically half the university students come out to see what these high school girls were trying to do on their large football pitch, and [they] were very impressed.”

Seeing the success of Team Ghana’s second launch made the STEMbees team want to expand its CubeSat program to reach even more students across Ghana, Amoako said. The organization partnered with AIMS Ghana and the U.S. Embassy in Ghana to create the Infinity Girls in Space Project. By August 2023, more than 110 girls from 37 schools across the country had learned about and helped build CubeSat prototypes.

Aerospace engineering and satellite imagery analysis are not commonly taught in primary or high school in Ghana, explained Lady-Omega Hammond, STEMbees product and start-up growth strategist. Unless a student goes into one of a few specific careers—for example, the military, telecommunications, or land surveying—“you might not find yourself, as a young person, wanting to think about what’s going on beyond the skies,” Hammond said. “CubeSats gave us a very interesting angle to pique the interest.”

As part of the Infinity Girls in Space Project, cohorts of high school girls across Ghana build and launch CubeSat prototypes. Credit: STEMbees

During Infinity Girls in Space, STEMbees provided CubeSat prototype training modules, lesson plans, assembly kits, and technical resources to teachers and students at more than 3 dozen high schools across Ghana. Students learned 3D printing, satellite assembly, coding, and basic physics and atmospheric science. Cohorts from several nearby schools, joined in person by STEMbees experts, worked together for the builds and launches. The eight cohorts lofted 10 CubeSat prototypes into the lower atmosphere by balloon, and they collected images and basic atmospheric readings before their teams retrieved them.

Although some students struggled initially because the concepts were new to them, “I think it all came together when they were working as a team” and supporting one another through the learning process, Amoako said.

“The pride and joy that you see when the parents are coming to see the end result of what their girls have created is always very heartwarming.”

“The pride and joy that you see when the parents are coming to see the end result of what their girls have created is always very heartwarming,” Hammond said. Some participants have graduated and gone on to study engineering.

At the university level, students who participate in CubeSat missions can explore more complex technical and science skills such as payload design, spacecraft assembly, launch testing, and data pipeline development. They can then leverage this hands-on experience into academic or aerospace industry jobs. Postdoctoral researchers and senior graduate students gain experience mentoring newer team members and also experience a space mission’s life cycle.

3UCubed has been in development for several years. After launch into low Earth orbit, the satellite will measure how particle precipitation affects the polar thermosphere and the lifetime of satellites at this altitude.

To date, 68 undergraduate students and two graduate students have been part of the 3UCubed team. They have gone through all stages of mission development, Lugaz said, from concept and design reviews, to building, programming, and testing. After launch, students will be involved with collecting and analyzing data and publishing the results.

The 3UCubed satellite, shown here in an artist’s rendering, is only 30 centimeters long. Credit: University of New Hampshire Teaching Future Teachers

TU Delft’s Da Vinci CubeSat offers those same experiences and skill development opportunities to its student team members, Bagchus said, and it also provides opportunities for those who want to become STEM educators.

“The goal of the satellite is, very simply put, purely educational,” Bagchus said. “We want to provide STEM education to inspire the future generation for STEM and also make them aware that space is literally all around them.”

Da Vinci is planned to launch in 2027 through a partnership with the European Space Agency. The 2U CubeSat will have two educational payloads: one geared toward primary schoolers and one for secondary schoolers. The team is writing and testing free lesson modules for each payload so that teachers and independent learners around the world can learn from the satellite. Members of the satellite team who want to become teachers themselves are gaining experience in developing lesson plans that incorporate satellite technology.

We asked the students, ‘What would you like to do in space?’ And the answer was, ‘I want to play in space.’”

“We did a primary school competition, and we asked the students, ‘What would you like to do in space?’” Bagchus explained. “And the answer was, ‘I want to play in space.’”

The team designed a payload that will allow students to roll dice in space. The satellite will send them pictures and videos of the dice rolling, so they can make statistical calculations and play chance games. The design involved figuring out the technical aspects of controlling a space-based dice roll from the ground and delivering the results in a way that’s accessible to primary schoolers.

The payload for secondary schoolers teaches them about how radiation in the space environment degrades digital photos when cosmic radiation strikes a pixel. One lesson plan for this payload guides students in developing computer code to restore image quality, similar to the Hamming codes used to process space telescope images—another practical lesson for students interested in space science.

The lesson plans and master classes for both modules will be available in-person and virtually.

“Not all people have the same access to education or can have their true potential achieved through education, because of where they were born, or maybe some personal issues they are facing,” Bagchus said. The Da Vinci satellite is “a beautiful initiative to at least try to help a little bit in that aspect.”

The Da Vinci CubeSat will have an educational payload tailored for primary school students that will allow them to roll dice in space. Credit: Da Vinci Satellite/TU Delft Launching into the Future

Some CubeSat prototypes are quick to develop. Others take years to complete. Case studies have found that lack of student training, time commitment constraints, and turnover from graduation can be challenges to CubeSat programs with longer lifespans. But using prototype kits and satellite simulators as well as dedicating time to hands-on training can overcome time and training issues, and turnover can provide an opportunity to get more students involved.

“You don’t find this in your everyday secondary school or even in university.”

“You don’t find this in your everyday secondary school or even in university,” Hammond said. The long-term influence of a CubeSat on its student team members might not be immediately clear, she said, “but I believe in a couple of years, it will definitely influence their thinking into why they chose a career in STEM or not.”

Phyllides, who joined 3UCubed last year, said she got involved with the program through a friend and had no experience with satellites when she started. Now, after more than a year calibrating the onboard instruments and analyzing test data, she’s eagerly awaiting the satellite’s launch.

“I want to see if the code that I’ve been writing will work and actually show our data,” she said. She hopes to analyze 3UCubed data as part of her senior project. “That would be like a huge, huge goal of mine.”

Last year, she presented on the 3UCubed mission at AGU’s annual meeting and found networking with other students involved with space missions to be a valuable experience. She’s still figuring out what she wants to do after graduation, but her work with 3UCubed has expanded her horizons.

“It’s really, really awesome,” she said. “I’m very, very lucky.”

—Kimberly M. S. Cartier (@astrokimcartier.bsky.social), Staff Writer

Citation: Cartier, K. M. S. (2025), Small satellites, big futures, Eos, 106, https://doi.org/10.1029/2025EO250359. Published on 29 September 2025. Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

CubeSats on The Rise

CubeSats, those boxy satellites that float above Earth alone or in miniature constellations, are emerging as little engines (without engines) of accessible education and affordable engineering.

“The goal from the get-go” of CubeSat education programs “is to give students hands-on experience, not just in building…but in the full life cycle of a mission,” says space scientist Noé Lugaz in Kimberly Cartier’s forward-looking feature “Small Satellites, Big Futures.” Such programs have reached those goals with successfully launched missions designed by STEM students from Saudi Arabia to Seychelles. And international CubeSat projects (as well as readily available hardware and innovative engineering) have expanded career opportunities for budding space scientists from Africa to Southeast Asia.

Other goals of CubeSat programs include the pursuit of economic and ecological sustainability. Wooden satellites, like the ones profiled in Grace van Deelen’s “A New Satellite Material Comes Out of the Woodwork,” might just do the trick.

In more terrestrial matters, a scientist-authored opinion considers the implications of land management in the Himalayas in “Beyond Majesty and Myths: Facing the Realities of Mountainside Development.”

This month’s articles offer a good reflection of Earth and space scientists in these uncertain times: excavating down-to-earth opportunities, reaching for the stars. I think I can, I think I can…

—Caryl-Sue Micalizio, Editor-in-Chief

Citation: Micalizio, C.-S. (2025), Squaring up in space, Eos, 106, https://doi.org/10.1029/2025EO250358. Published on 29 September 2025. Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: AGU Advances

Only big impactors can punch their way through Venus’s atmosphere. When they do, the impact lofts dust which is then blown downwind as it drifts back to the surface. The resulting parabola-shaped dust deposits are unique to Venus and indicate the wind direction at the time of impact.

In a clever study, Austin et al. [2025] show that the parabolas that appear oldest and most degraded depart most strongly from the expected wind direction. This suggests that wind directions on Venus have changed over time – but why? Because of Venus’s slow spin, its rotation axis is unstable. The authors suggest that the parabolas are recording winds from a period when Venus’s rotation axis was somewhere else. Future Earth-based or spacecraft observations might be able to test this theory.

Citation: Austin, T. J., O’Rourke, J. G., Izenberg, N., & Silber, E. A. (2025). Survey and modeling of windblown ejecta deposits on Venus. AGU Advances, 6, e2025AV001906. https://doi.org/10.1029/2025AV001906

—Francis Nimmo, Editor, AGU Advances

Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.