California could be due for a major earthquake in the near future, according to concerning new models based on data comprising 1,000 years of quake activity on the West Coast.

According to recent findings, tectonic stress has quietly been building in California to levels not seen since the last major earthquake in the region, which bore a magnitude of 7.9 and struck the West Coast nearly 170 years ago.

That event, known as the Fort Tejon earthquake, affected the greater Los Angeles area, and since the time of those historic rumblings, researchers have grown increasingly concerned about a period of seismic silence that could point to the likelihood of an event of similar magnitude at some point in the future.

The potentially concerning new forecast was detailed in a recent study by an international team of researchers led by Dr. Liliane Burkhard of the Division of Space Research and Planetary Sciences (WP) at the Physics Institute of the University of Bern, which focused on historic earthquake data as a means of gauging current stress loading at Cajon Pass.

The study, published in the Journal of Geophysical Research: Solid Earth, indicates tectonic stress levels that are now believed to exceed the highest seen during the years the team surveyed.

The “Earthquake Gate” at Cajon Pass

The researchers aimed to investigate stress that has slowly built along the San Andreas and San Jacinto faults and incorporated what they likened to an “earthquake gate” at Cajon Pass, which, in their models, functioned like a point of control that governed the size of earthquakes and whether they could spread to both systems.

For their research, they used a four-dimensional earthquake cycle model that allowed them to replicate certain processes both in spatial dimensions and across time.

Using a millennium of reconstructed earthquake data from the region based on geological information such as radiocarbon dates, unusual events recorded in dendrochronological data (i.e., information obtained from tree rings), and historical information sources, the team gave this to the model they devised.

Dr. Burkhard said the team’s simulation offered them a unique opportunity to better understand the ways stresses in the fault system build up over long periods of several centuries.

“By running the earthquake history of Southern California as a simulation, we can estimate the extent to which the fault system is already under stress today,” Dr. Burkhard said. The results of those simulations weren’t particularly promising either: according to Burkhard, current stress levels in the region are the highest they have been in 1,000 years, based on the data.

Concerning New Earthquake Data

The team also identified significant new information regarding the function of the so-called “earthquake gate” at Cajon Pass.

“The earthquake gate concept captures something important about how fault junctions work,” Burkhard said in a recent statement. “Cajon Pass doesn’t simply block or channel earthquakes: It responds to stress conditions, and those conditions change over centuries.”

Not only this, but Burkhard and her team also determined that a key element to these quakes involves not only the level of stress that accumulates at a single fault, but perhaps more significantly, the way stress between two systems can align. This is because, as the stress across a pair of faults rises together over longer periods, this appears to be most conducive to a large joint rupture comparable to the 1857 Fort Tejon earthquake.

Conversely, if stress levels are not in concert as they evolve, the team determined that this causes quakes that probably will not propagate beyond the junction.

In short, a more severe earthquake event today would entail a joint rupture that crosses the Cajon Pass, as opposed to one constrained either to the San Andreas or the San Jacinto Fault alone. Should such an event occur, it would likely impact one of the largest population centers, as well as a crucial infrastructure system that supplies energy and transportation to surrounding areas.

For Burkhard, “The question of when and how the next major earthquake will occur in this region is one of the most pressing problems in applied geoscience.” Based on the team’s findings, they say that their new modeling hopes to provide a much more complete picture of the science behind the factors that could lead to a major quake—conditions that could apply equally to other parts of the world as they do to California.

Burkhard adds that her team’s study is not intended merely as a prediction for when the next major earthquake could potentially occur, but also as a means of preparing for future quakes and mitigating their effects.

“What we can say is that the system is critically stressed and that physics-based models like ours give a clearer picture of the range of scenarios we should be prepared for,” Burkhard says. “This information is important for hazard assessment, infrastructure planning, and emergency preparedness.”

The team’s study, “Cajon Pass and the Southern San Andreas Fault System: Earthquake Cycle Stress Accumulation and Present‐Day Loading,” appeared in the Journal of Geophysical Research: Solid Earth.

Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.

Massachusetts Institute of Technology (MIT) engineers are testing a new category of advanced-propulsion “electrospray” thrusters that combine the benefits of modern chemical and electrical thrusters used to drive satellites and other spacecraft into one hybrid system.

The team behind the novel propulsion technology said that electrospray thrusters could allow mission planners to design smaller, more nimble satellites and spacecraft capable of performing faster, more powerful maneuvers or slower, more precise adjustments, depending on mission requirements.

Electrospray Combines the Best of Chemical and Electric Propulsion

Launching rockets into space still requires chemical thrusters, but once spacecraft and satellites reach orbit, engineers continue to develop novel propulsion methods that are more efficient than chemical propulsion technologies. Given the strict weight requirements of spacecraft launches, finding alternatives to chemical propellants has opened up a wider range of mission profiles.

Among the most common alternatives to chemical thrusters are designs that combine electrical energy with small amounts of propellant to produce small but sustainable thrust. Although electric thruster designs require less fuel, saving significantly on launch weight, they also lack both the power and the rapid, quick burst performance of chemical thrusters.

According to study author Amelia Bruno, a former postdoc in MIT’s Department of Aeronautics and Astronautics (AeroAstro), combining chemical and electrical propulsion into a single system is “the best of both worlds.”

“This opens the door for small satellites to do even more science, more observations, and more interesting missions, all on a smaller and cheaper platform,” Bruno explained to MIT News.

Study co-author Paulo Lozano, the Miguel Alemán Velasco Professor of Aeronautics and Astronautics at MIT, agreed, noting that combining both technologies could enable a CubeSat mission to Mars “where they could make the journey slowly, using electrospray thrusters.”

“You could then use your chemical thrusters to quickly move to look at interesting features,” the professor added. “You could have a lot more flexibility to do a lot more things.”

ASCENT Rocket Fuel as the Thruster’s Ionic Liquid Propellant Enables Hybrid Design

According to a statement detailing the new electrospray thruster’s design, the ones developed by the MIT team are about the size of a thumbnail. Each thruster is also placed directly above a small fuel reservoir. For the MT electrospray thrusters, the fuel is an ionic liquid propellant, a liquid composed of salts that remain dissolved in a solution.

“Ionic liquids are very stable and can even remain a liquid in space, which not a lot of materials can do,” Bruno explained. “And it’s basically a sea of ions, which is why we base our technology around it, so we can pull those ions out into an electrospray.”

When a spacecraft’s battery delivers an electric charge to the fuel reservoir, the ions within the fuel also become charged. The thruster’s design channels the charged particles from the reservoir and through the thruster tips, expelling them into space.

Although the team has tested several types of ionic propellant in its electrospray propulsion thrusters, Bruno and Lozano have collaborated with the U.S. Air Force to synthesize an all-new ionic liquid propellant, which they are calling the Advanced SpaceCraft Energetic Non-Toxic propellant, or ASCENT.

Originally designed as a “green” alternative to extremely hazardous hydrazine rocket fuel that has been the staple in the rocket industry for decades, Bruno notes that ASCENT “happens to be an ionic liquid mixture.”

“And we said, hey, that’s the stuff we typically use,” the researcher added. “Theoretically, this should work. Let’s go figure out how.” 

Tests: Chemical Propellant Equally Efficient as Conventional Ionic Liquids

To test their electrospray design, each tested thruster was attached to a small reservoir about the size of a single Lego brick, and then the reservoir was filled with ASCENT. Next, electrospray thrusters were mounted on opposite sides of a traditional CubeSat.

To simulate the microgravity environment of Near-Earth Orbit, the team placed the thruster-equipped CubeSat on a MagLev stand. The team noted that the MagLev in Lozano’s lab is installed inside a large vacuum chamber. This design allows the researchers to fine-tune the environment to best mimic the conditions in space.

During a series of tests, the team applied varying voltage levels to the electrospray thrusters. As expected, the reaction produced a spray from the thruster nozzles, which spun the CubeSat around on the MagLev stand like a freely spinning top.

During each thruster firing, the team measured the amount of thrust produced. This data, combined with the voltage and fuel data, allowed the team to calculate ASCENT’s fuel efficiency during continuous operation. Some tests lasted up to 100 hours.

When the MIT group evaluated the results, they first determined that the choice of ASCENT was correct, as it successfully fueled each electrospray thruster. Even more significantly, the tests revealed that the readily available chemical propellant was equally efficient as conventional ionic liquids.

“Compared to our normal electrospray propellants, ASCENT can provide similar performance in terms of thrust,” Bruno explained. “Now that we know our thrusters work with ASCENT, we can start thinking of all the ways we can make them even better.”

Testing Electrospray Thrusters on NASA’s Green Propulsion Dual Mode Mission

When discussing the benefits of their successful electrospray thruster tests, Lozano noted that a spacecraft with electric and chemical thrusters can share a single fuel tank. Due to its compact design, this hybrid electrospray thruster could be mounted on a small satellite.

Fortunately, the team won’t have to wait long to see their thruster in action. According to the research team, whose work was partially supported by NASA, their design will be incorporated into NASA’s upcoming Green Propulsion Dual Mode mission scheduled to launch in November. The Green Propulsion Dual-Mode mission will carry a briefcase-sized CubeSat with a primary chemical thruster and specially designed electrospray thrusters, making it the first attempt to combine electrical and chemical propulsion in a small spacecraft.

“This will be the first time that a satellite will have a shared propellant tank,” Lozano explained.

Although a large portion of proposed electric propulsion missions that might employ the new electrospray thruster are designed to explore deeper into the Solar System and beyond, Lozano also highlighted the technology’s possible applications closer to home. For example, satellites equipped with both technologies could rapidly respond to environmental or climate changes in real time with a speed and efficiency unavailable with current propulsion options.

“Say there’s a storm coming, and you’d want to deploy your constellation of small satellites to observe over one location,” the researcher explained. “You could choose to send them quickly or slowly, depending on the nature of the observation.”

“And the only way to do that is if you have two propulsion systems, which is now possible,” he added.

Although the mission will not launch before November, Bruno noted that a successful test could allow engineers to consider missions they never thought possible.

“Now that we know our thrusters work with ASCENT, we can start thinking of all the ways we can make them even better,” the researcher explained.

The study “Performance Characterization of Electrospray Thrusters with Energetic Ionic Liquid Monopropellant” was published in the Journal of Propulsion and Power.

Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.

The ancient history of our planet’s impact events is coming into focus, thanks to researchers who have triangulated similarly aged impacts on Earth, the Moon, and the asteroid 4 Vesta in a new study.

The lunar meteorite NWA 12593 correlates not only with impact events observed across three locations in our solar system but also contains evidence of three separate impact events that occurred at different times.

The findings, revealed in a recent paper published in Geology, show that scientists are using this new impact data to fill in the volatile early-Earth period when life began.

Early Earth Impacts

The Archean period, roughly 4 to 2.5 billion years ago, was a consequential time from which our earliest fossil records date, corresponding to around 3.5 billion years ago. Researchers believe that life likely first arose at this time, yet it may have faced adversity from bombardment by space rocks between 3.2 and 3.5 billion years ago, although scientists disagree on how intense this impact activity was.

Our planet’s geological activity eventually destroys evidence of the ancient past through erosion, subduction, and burial, continually reshaping the surface. Yet those early years are essential to understanding the origins of water, atmospheres, and life on Earth. 

“On Earth, the first fossil evidence of life shows up around 3.5 billion years ago, meaning that life is emerging and evolving before then. The question that we often have, even going back further, is what was the impact record when life was emerging?” said lead author Carolyn Crow, a planetary scientist at the University of Colorado Boulder.

“It is important for understanding how life is taking hold, how life is emerging,” Crow added. “The cadence of these catastrophic events is an important part of the equation.”

A Neighbor Remembers

While Earth’s surface is constantly renewed by geological processes, our nearest significant neighbor, the Moon, is much more stable, retaining its geological record for longer periods. Because of this, lunar meteorites provide a resource for scientists to understand the impact of Earth and the inner solar system by matching them to known impacts on our planet and in the asteroid belt.

For the recent study, the team focused on a lunar meteorite discovered in northwest Africa, designated NWA 12593, and identified three separate impact events in a single sample. 

Radiometric dating traced the oldest to 3.5 million years ago, intriguingly close to the time of the earliest known fossils. Extraordinary in power, this impact produced the mineral zirconia by melting the lunar surface into a lava-like flow. Without the precise laboratory conditions required to produce stable cubic zirconia, only traces of mineral remained in the sample.

According to the team, the first impact aligns with previously known impact events on Earth, and the fourth-largest object in the asteroid belt, 4 Vesta. It’s extremely rare to find such corresponding evidence between three bodies, providing important data on this time of frequent collisions.

“It’s not very common, which is why we’re very excited about it,” says Crow. “It’s pretty rare to have all three records line up like this.”

Later Impacts

Evidence of later impacts included breccia composed of large, angular, broken mineral fragments cemented together. The team believes the breccia resulted from a second impact that struck the melt sheet formed by the first.

“Breccias are similar to what you would see if you went and chipped out a chunk of concrete. You would see all these little rocks, and then it’s fused together by the cement,” says Crow. “But the meteorite is fused together by the impact process. You get all these chunks of different kinds of rocks that the impact hit into. These all get mixed up, and then it gets fused together like your concrete sidewalk.”

As for the third impact, the evidence for this is the meteorite’s mere presence on Earth; an event that occurred some time after the first would have ejected the lunar breccia, the researchers say, allowing it to eventually land on our planet.

In total, the sample reveals an intriguing impact history, preserving a record of bombardment that provides solid evidence for a flurry of activity in the inner solar system during a violent chapter in the early history of our Solar System.

The paper, “Three-Body Evidence of Ca. 3.7 Ga to 3.2 Ga Bombardment Across the Inner Solar System,” appeared in Geology on May 12, 2026.

Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.

A curious recent discovery has revealed a promising new underground archaeological find at the ancient site of Buto in Egypt’s Nile Delta.

Researchers who were testing a remote sensing technology designed to locate buried structures and other below-ground features reported the unique find earlier this year, which could be a previously undiscovered tomb or temple now believed to date as far back as 2,600 years.

The discovery was made at the Tell el-Fara’in site, more commonly known as Buto, which comprises the remains of an ancient city that thrived around 5,600 years ago during Egypt’s Predynastic period.

Origins of a Mystery

Buto underwent several periods of destruction and reassembly throughout its history, making it a significant focus of past archaeological work.

Some of the city’s oldest portions are currently entombed beneath several centuries’ worth of accumulated mud and soil, a factor that significantly complicates traditional excavations. To help them locate an ideal location for future excavation, the team employed an approach that combined SAR (Sentinel-1 GRD) satellite imagery with electrical resistivity tomography (ERT) measurements, which helped them pinpoint an ideal location to dig that would best enable an investigation of Buto’s settlement phases.

“Sentinel-1 (C-band) satellite imagery captured on May 5, 2018, was processed using SNAP software (version 9.0.0) to identify large-scale anomalies indicative of buried structures,” the team reports in a paper detailing their findings, which appeared in Applied Geophysics in March.

“Based on these detected anomalies, the locations for ERT profiles were strategically selected to maximize the likelihood of indicating significant subsurface features,” the team explained.

ERT technology is ideal for such carefully targeted excavation, since it relies on electrical currents placed into the ground, which researchers then use to collect data that helps them assemble a three-dimensional model of the buried structures. This imagery is generated based on differences in the way various materials either display electrical conductivity or resistance.

Buried Discoveries Emerge

Based on the team’s scans, the top three meters of the area revealed a distinctive layer of material, which the team judged to be broken pottery and debris—likely associated with Roman periods of occupation.

However, going further down in their scans, descending to a depth of approximately six meters, the team discovered something more intriguing: what appeared to be some kind of large buried structure.

Based on its depth, the team believes this unique structure is likely associated with the Saite period, which dates it to around 2,600 years ago. Although it remains unknown precisely what the structure is, or what its exact purpose may have been, one possibility is that it could be a large shrine, or even a tomb.

Uncovering Religious Artifacts

Following the initial discovery, the team undertook preliminary excavations of a small 10 x 10-meter area. This revealed walls constructed of mudbrick, as well as religious artifacts in locations that aligned with the team’s scans.

“The presence of a small offering basin along with numerous religious amulets depicting Egyptian deities such as Isis, Horus, Taweret, and Wadjet further supports the temple hypothesis,” the team writes in their study.

Also among the religious artifacts uncovered at the site were a “remarkable bronze amulet with a suspension hole, representing Horus the child” as well as amulets featuring a crouching lion, an amulet of Anubis, and the remains of limestone statues “in sexual positions” along with “a faience plaque with relief carvings of Hathor on both sides.”

However, the team reports that one of the most significant artifacts recovered from this area of the excavation was a steatite scarab bearing the name of King Thutmose III, which the team believes “may have functioned as an amulet or seal.”

“Collectively, these artefacts indicate the presence of a religious site with strong cultic and ceremonial associations, further reinforcing the interpretation of the structure as a temple from the 26th Dynasty,” the team says.

Ongoing Excavations

While still in the early phases, the team’s discoveries so far help to validate the geophysical and remote sensing techniques that made the discovery possible. “The results of this study demonstrate the effectiveness of combining geophysical measurements and remote sensing data,” the team writes, adding that they provided “a very accurate vision in detecting buried settlements in a complex region.”

“3D inversion algorithms were particularly effective in delineating buried mudbrick walls and architectural structures, significantly enhancing our understanding of site formation processes,” the researchers add.

Going forward, the team recommends further ERT surveys, which may help to reveal additional information about the site’s deepest occupation levels. For the time being, the team believes the evidence in hand points to the interpretation of the site and its features as an ancient temple, and that evidence points to the possibility that another may be located nearby.

“Our findings suggest that, in addition to the known temple, another temple may remain buried under a thick clay layer, which will be investigated through extensive measurements in forthcoming studies,” the team writes.

The recent paper, “Multi-scale detection of buried archaeological elements across different occupation phases: an integrated approach using radar satellite imagery and electric resistivity tomography at Buto, northwestern Nile Delta of Egypt,” appeared in Applied Geophysics on March 10, 2026.

Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.

An unexpected human behavioral tendency to prefer turning counterclockwise rather than clockwise has been uncovered by a team of researchers in Spain and Japan, and its cause remains unknown.

In a recent paper published in Nature Communications, the team sought to identify patterns in individual human behavior among large crowds and determine which factors influence them. Surprisingly, the team found that counterclockwise turning is the overwhelmingly common behavioral preference, regardless of gender or culture, with only age making a slight difference.

An Unexpected Behavior

The team’s work could have ramifications not only for psychology but also for architecture, engineering, and design, enabling more intuitive layouts. Work on the project began at Spain’s University of Navarra, before experiments continued at the University of Tokyo in Japan.

The University of Navarra team discovered the phenomenon entirely by accident while researching social distancing during the COVID-19 pandemic. Initially, their interest was in monitoring how effectively the recommended six-foot spacing could be maintained in public spaces. They observed how humans moved through spaces, such as museums, without a set route. While closely monitoring crowd video, they were surprised to witness the counterclockwise trend emerge.

“When analyzing the experiments, my colleagues realized by chance that in 32 out of 33 experimental trials, as people moved and turned, they noticeably preferred to turn counterclockwise,” said co-author Professor Claudio Feliciani from the University of Tokyo’s Department of Aeronautics and Astronautics.

“This was completely unexpected as, at least instinctively, when people walk around randomly, you imagine people turn as their needs suit them with little sign of an overall preference,” Feliciani added. “But there was a definite, measurable tendency for people to turn counterclockwise over clockwise, all things being equal.”

Exploring Internationally

With their curiosity piqued, the University of Navarro team sought to test their findings against further observations to determine which factors might be influencing the behavior. They decided to seek international follow-up observations. This brought them into contact with Claudio Feliciani, whose presence in Tokyo would allow the project to test how the trend played out across cultures, and among other factors. 

For the second stage of the project, Feliciani and his team developed a series of experiments targeting age, handedness, gender, group size, and cultural influence. They observed pedestrian test subjects in both constrained and open environments.

“Of all these things, the only thing that stood out was that kids tend to have a stronger bias for the counterclockwise direction, so probably age plays a role in making the effect weaker or stronger,” said Feliciani. “Our results may appear as a minor, insignificant discovery, but in nature, most phenomena related to locomotion show that animals mostly walk without directional preference.”

“The strong bias found in people hints to some asymmetry at the biomechanical level,” Feliciani added.

Unknown Behavioral Causes

With the international project having confirmed the counterclockwise trend, the researchers are now moving on to more granular exploration of the phenomenon at the individual level. They hope that this more individualized research will yield some information on what biomechanical factors may be driving the behavior.

“It likely does not come from the eyes, because we tried to patch people’s left or the right eyes and the bias was still there,” Feliciani said. “And some people asked us if it might be large-scale phenomena like the Coriolis force or Earth’s magnetic field, but this seems unlikely given what we have managed to point to so far. “

Both lead investigator Iñaki Echeverría Huarte and Feliciani say that the Coriolis effect has become something of a joke among the team, and that they are invariably asked about it when presenting their findings.

“As a curious aside, a friend and collaborator in Argentina was intrigued enough to run some similar experiments when he heard about this,” Huarte told The Debrief of the team’s research in an email. “He tells me that, with no proper scientific confirmation yet, the counterclockwise rotation still seems to be there in the southern hemisphere too.

“There are some interesting parallels to certain sports,” Feliciani concluded. “Some running and driving competitions are always, but inexplicably, taken on courses that run counterclockwise. But that’s an investigation for another time.”

The paper, “Individual Locomotor Bias Drives Counterclockwise Motion in Pedestrian Crowds,” appeared in Nature Communications on June 10, 2026.

Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.