A clinical trial published in The Lancet Rheumatology suggests that a small, carefully chosen adjustment to the angle of your feet could make a meaningful difference. After one year, participants who learned to walk with a personalized foot position reported significantly less knee pain than those receiving a placebo treatment. They also showed encouraging signs of slower deterioration in their knee cartilage.

The pain relief was comparable in magnitude to benefits reported for some commonly used medications. More importantly, the approach may help address something painkillers cannot: the excessive pressure on knee joints that contributes to osteoarthritis progression.

A Simple Walking Change Could Help Fight Knee Arthritis

Osteoarthritis affects roughly 22% of adults over age 40 and is one of the leading causes of disability. The condition gradually damages cartilage, the smooth, protective tissue that cushions the ends of bones and allows joints to move with minimal friction.

As cartilage deteriorates, everyday activities such as walking, climbing stairs, and getting out of a chair can become increasingly painful. Although exercise, physical therapy, weight management, and medications can help manage symptoms, there is currently no established treatment that reliably restores cartilage lost to osteoarthritis. People with advanced disease may eventually need joint replacement surgery.

Researchers from the University of Utah, New York University, and Stanford University have investigated a different strategy called gait retraining. Rather than focusing only on relieving pain, this approach changes the mechanics of walking to reduce pressure on vulnerable parts of the knee.

The findings, published in August 2025, came from the first randomized, placebo-controlled clinical trial to demonstrate the effectiveness of personalized gait retraining for knee osteoarthritis over a full year.

The research was co-led by Scott Uhlrich, an assistant professor of mechanical engineering at the University of Utah’s John and Marcia Price College of Engineering, with collaborators at Stanford and New York University. The work received support from federal research agencies, with the U.S. Department of Veterans Affairs listed as the trial’s funder.

“We’ve known that for people with osteoarthritis, higher loads in their knee accelerate progression, and that changing the foot angle can reduce knee load,” said Uhlrich, an assistant professor of mechanical engineering. “So the idea of a biomechanical intervention is not new, but there have not been randomized, placebo-controlled studies to show that they’re effective.”

Why the Angle of Your Feet Matters

The secret lies in how body weight moves through the knee with each step.

The knee has an inner section, called the medial compartment, and an outer section, known as the lateral compartment. During normal walking, the inner section typically carries more of the load. This helps explain why osteoarthritis affecting the inside of the knee is especially common.

For people with this type of arthritis, repeatedly placing excessive pressure on the already damaged area can accelerate deterioration.

Changing the direction in which the toes point during walking can redistribute some of that pressure. Turning the toes slightly inward or outward alters the forces acting on the knee, potentially reducing stress on the affected cartilage.

However, there is an important catch: the same adjustment does not work for everyone.

Some people benefit from turning their toes inward, while others respond better when their toes point farther outward. Making the wrong adjustment could fail to help or even increase pressure on the damaged joint.

“Previous trials prescribed the same intervention to all individuals, resulting in some individuals not reducing, or even increasing, their joint loading,” Uhlrich said. “We used a personalized approach to selecting each individual’s new walking pattern, which improved how much individuals could offload their knee and likely contributed to the positive effect on pain and cartilage that we saw.”

How Scientists Found the Right Walking Pattern

The researchers focused on people with mild to moderate osteoarthritis affecting the inner part of the knee.

At their first two laboratory visits, participants underwent MRI scans and walked on a specialized treadmill equipped with sensors that measured the forces generated during each step. Motion capture cameras recorded their movements in detail, allowing the researchers to analyze how different walking styles affected the knee.

Participants tested small changes in their foot position, turning their toes inward or outward by either 5° or 10°.

The scientists then identified which adjustment reduced pressure on the affected knee most effectively for each person.

Not everyone qualified. Some prospective participants were excluded because none of the tested adjustments successfully reduced their knee loading. Including such individuals in earlier studies may help explain why previous attempts at gait retraining produced inconsistent results.

After the initial assessments, 68 participants were randomly divided into two groups of 34.

One group received personalized instructions designed to minimize stress on the inner knee. The other received a sham treatment, meaning they went through the same training process but were instructed to maintain their natural foot angle.

This comparison allowed the researchers to separate the benefits of changing walking mechanics from improvements caused by expectations, attention from researchers, or participation in a structured walking program.

Just Six Weeks of Training Changed How They Walked

Both groups attended six weekly training sessions.

During these visits, participants walked on a treadmill while wearing a small device on their shin. The device provided biofeedback, delivering gentle vibrations whenever their foot moved outside the prescribed angle.

Biofeedback is a technique that uses immediate signals to help people recognize and gradually control movements they normally perform without thinking.

Over time, participants learned to maintain their assigned foot position without needing constant reminders.

After completing the six weeks of supervised training, they were encouraged to practice their walking technique for at least 20 minutes each day until it became a natural habit.

Follow-up assessments indicated that participants were remarkably consistent. On average, they maintained their prescribed foot angles to within approximately one degree.

That consistency is important because the potential benefits depend on continuing the altered walking pattern during ordinary daily activities, not just during laboratory sessions.

Arthritis Pain Improved, and Cartilage Showed Less Damage

One year after starting the program, participants returned for another MRI and reported how much knee pain they were experiencing.

The results showed a meaningful advantage for those who received personalized gait retraining.

On a pain scale from zero to 10, participants in the intervention group reported an average improvement of 2.5 points, compared with 1.3 points in the sham group.

In an exploratory analysis, approximately 91% of participants receiving personalized retraining experienced a clinically meaningful reduction in pain, compared with 66% in the comparison group.

The researchers also found that the intervention reduced a mechanical measure associated with pressure on the inner knee, confirming that the altered walking pattern had effects beyond participants’ perceptions of pain.

“The reported decrease in pain over the placebo group was somewhere between what you’d expect from an over-the-counter medication, like ibuprofen, and a narcotic, like OxyContin,” Uhlrich said. “With the MRIs, we also saw slower degradation of a marker of cartilage health in the intervention group, which was quite exciting.”

The MRI findings may be especially important.

Researchers used advanced imaging techniques capable of detecting subtle changes in cartilage composition before major structural damage becomes visible on conventional scans.

One measurement, known as T1rho, suggested that cartilage in the inner knee deteriorated more slowly among participants who changed their walking pattern. A second MRI measurement did not show a significant difference between the groups.

These findings do not establish that damaged cartilage was rebuilt or that arthritis progression can be permanently stopped. However, they raise the possibility that reducing mechanical stress could help preserve cartilage health over time.

The treatment also appeared generally well tolerated. No severe adverse events were reported, although two participants in the intervention group and one in the sham group withdrew because of increased knee pain.

More Recent Research Adds to the Evidence

Research published since the 2025 trial has provided further insight into how walking modifications might help people with knee osteoarthritis.

In a separate randomized trial published in Clinical Biomechanics in April 2026, researchers at the University of Bath investigated different types of biofeedback training in 50 people with knee osteoarthritis.

Participants completed a six-week program using different feedback strategies intended to improve walking mechanics.

All three groups, including the control group, experienced improvements in activity-related knee pain and physical function. However, only the group receiving feedback about its walking pattern achieved a lasting reduction in a key measure of knee loading.

That group’s knee loading measure fell by 7.6%, with the improvement maintained at a follow-up assessment one month later.

Interestingly, the investigators did not detect significant changes in foot angle in any of the groups. This suggests that other adjustments to walking mechanics can also influence the forces acting on the knee.

The findings reinforce an important lesson from the 2025 trial: simply encouraging people to walk differently is not necessarily enough. The type of movement being taught, and whether it successfully reduces harmful joint loading, appears to matter.

The 2026 study did not examine long-term cartilage deterioration, so it cannot establish whether these additional walking strategies slow osteoarthritis progression.

Could This Help People Avoid Knee Replacement?

For people living with knee osteoarthritis, the appeal of this approach extends beyond its measurable effects in the laboratory.

One trial participant described the freedom of adopting a treatment that did not require medication or an assistive device:

“I don’t have to take a drug or wear a device…it’s just a part of my body now that will be with me for the rest of my days, so that I’m thrilled with.”

Once a person learns the technique, it can potentially become part of ordinary daily movement without requiring continued use of specialized equipment.

That could be particularly valuable for people who develop arthritis relatively early in adulthood.

“Especially for people in their 30s, 40s, or 50s, osteoarthritis could mean decades of pain management before they’re recommended for a joint replacement,” Uhlrich said. “This intervention could help fill that large treatment gap.”

Whether gait retraining can actually delay or prevent knee replacement remains unknown. Longer studies would need to demonstrate that its benefits persist and translate into better joint health and fewer surgical procedures.

Still, the prospect of relieving pain while potentially slowing cartilage deterioration makes personalized walking adjustments an intriguing addition to the available treatment options.

Smart Shoes and Smartphone Cameras Could Make Treatment Easier

One major obstacle remains: delivering personalized gait retraining outside a specialized research laboratory.

The original trial relied on sophisticated motion capture equipment, pressure-sensitive treadmill measurements, MRI scans, and repeated in-person visits. Those resources are expensive and difficult to provide in ordinary physical therapy clinics.

Researchers are exploring ways to make the technology much simpler.

“We and others have developed technology that could be used to both personalize and deliver this intervention in a clinical setting using mobile sensors, like smartphone video and a ‘smart shoe’,” Uhlrich said.

Smartphone cameras could help analyze walking mechanics and estimate how different movements influence knee loading. Meanwhile, shoes fitted with motion sensors could provide feedback as patients practice walking at home or around their neighborhoods.

Work published in Machine Learning with Applications in September 2026 explored another possibility: using artificial intelligence to estimate knee loading from acceleration measurements collected at the foot.

In that proof of concept study, researchers analyzed walking data from 10 healthy adults and demonstrated that a machine learning system could track changes in estimated knee forces across different walking patterns.

The technology remains experimental and has not yet been validated as a treatment tool for people with knee osteoarthritis. Nevertheless, it illustrates how future rehabilitation systems might provide personalized guidance without requiring a room full of cameras and laboratory equipment.

A Promising Treatment, but Not a Do-It-Yourself Fix

Despite the encouraging results, researchers caution that personalized gait retraining is not yet ready for widespread clinical use.

The original study included only 68 participants, all of whom had mild to moderate osteoarthritis affecting the inner knee and demonstrated that at least one tested walking adjustment could reduce their joint loading. Its findings may not apply to people with advanced arthritis, other patterns of joint damage, or those whose knees respond differently.

Importantly, turning the toes inward or outward without professional assessment is not the same as receiving personalized gait retraining. An adjustment that helps one person might increase stress on another person’s knee.

Larger trials, longer follow-up periods, and practical methods for delivering the treatment will be needed before clinicians can routinely prescribe it.

For now, the research points to an intriguing possibility: the way people walk may influence not only how much their knees hurt today, but potentially how well their cartilage holds up in the years ahead.

For more than seven decades, fusion researchers have relied on a mathematical rule to determine whether plasma can remain sufficiently hot and dense, for a long enough period, to sustain fusion without additional external heating. Known as the Lawson criterion, this equation defines the conditions required for ignition. However, it does not explain the most efficient way to achieve them.

Now, PPPL physicists Luis Delgado-Aparicio, Masayuki Ono, and Jonathan Menard have developed a more comprehensive version of the criterion. By incorporating four additional factors that influence fusion performance, they have mapped a promising route to ignition that could require substantially less energy than alternative approaches.

Their findings were published in the journal Physical Review Letters.

The research focuses on plasma, often called the fourth state of matter. Plasma forms when a gas becomes so energetic that its particles carry electrical charges. In fusion reactors, this extremely hot material contains the atomic nuclei that researchers hope to combine, releasing energy through nuclear fusion.

The ultimate goal is to produce a burning plasma, in which fusion reactions generate enough heat to sustain the process without continued external heating. Reaching this state efficiently remains one of the most important challenges in fusion energy research.

Scientists Find a Shortcut to Fusion Ignition

Delgado-Aparicio compares the discovery to finding a more efficient route through a mountain range.

Imagine that the energy requirements for fusion ignition form a landscape dominated by a towering mountain. The destination lies on the other side, but there are several possible routes to reach it.

Many proposed fusion strategies effectively attempt to climb directly over the mountain. They begin by increasing the density of the plasma and then supplying the enormous amount of heat needed to reach ignition.

The new calculations suggest that a different sequence could be considerably more efficient. Instead of increasing density first, researchers could heat the plasma before making it denser. This alternative route avoids the highest energy requirements while still reaching the desired conditions.

“A lot of companies want to climb the mountain head-on and spend enormous energy to get there,” Delgado-Aparicio said. “Go around the peak instead. You reach the same place in a much smarter way, and you use far less energy.”

The Hidden Mountain Pass in Fusion Physics

The researchers identified a particularly important region of this mathematical landscape called the Cordey saddle.

In geographical terms, a saddle is a low passage between higher elevations. In fusion physics, the Cordey saddle represents a relatively accessible point along the boundary separating plasma that still needs outside heating from plasma capable of sustaining its own fusion reactions.

To evaluate different routes, the scientists used a measurement called Q, which compares the power produced by fusion reactions with the external heating power supplied to the plasma.

For example, a Q value of 5 means the fusion reactions produce five times as much power as the external heating system delivers.

In an idealized plasma containing only pure fusion fuel, the Cordey saddle occurs at approximately Q = 5. However, actual fusion systems are much more complicated. Contaminants within the plasma and extremely strong magnetic fields can shift the location of this passage, increasing the Q value needed to reach it.

Understanding how these conditions change is essential for determining whether a proposed fusion reactor can realistically achieve ignition.

A More Realistic Roadmap for Future Fusion Reactors

The findings could influence the design of two major types of magnetic fusion devices: tokamaks and stellarators.

Both approaches use powerful magnetic fields to confine plasma while it is heated to the extraordinary temperatures needed for fusion. Tokamaks, which have a characteristic doughnut shape, are among the leading technologies being investigated for future fusion power plants.

Research institutions and private companies are pursuing several different ways to generate electricity from fusion and eventually deliver that power to the electrical grid. Identifying an efficient route to ignition could help engineers design more practical systems while avoiding costly mistakes.

For PPPL, this work is part of a broader effort to address the scientific and technological challenges that must be overcome before commercial fusion power becomes possible, including the development of future fusion pilot plants.

One of the study’s major advances is that it evaluates several important physical processes together rather than examining them separately, as much previous research has done.

The researchers incorporated four additional factors that can influence whether a plasma reaches and maintains ignition:

1. Helium ash buildup: Fusion reactions produce helium as a byproduct. As this spent fuel accumulates, it can dilute the remaining fusion fuel and reduce performance.
2. Plasma contamination: Light and heavy impurities can enter the plasma from materials lining the inside of the reactor, interfering with fusion conditions.
3. Synchrotron radiation: Electrons traveling through magnetic fields emit radiation, carrying energy away from the plasma.
4. Heat loss: Energy continuously escapes from the plasma, and these losses can become greater as its temperature rises.

Accounting for these effects produces a more realistic picture of the conditions future reactors must achieve.

“When you leave these effects out, you say the design will work fine,” Ono said. “When you put them in, the picture changes, and it becomes quite important.”

According to Ono, the goal is to establish a more reliable, widely applicable model that scientists can use to evaluate fusion reactor designs before construction begins.

Treating the Lawson criterion as a single unchanging threshold overlooks physical processes that can substantially alter the requirements for ignition. Including those effects early in the design process could prevent expensive problems later.

“Fusion experiments cost a great deal of money, and you do not want to make mistakes you could have caught beforehand,” he said.

Tiny Amounts of Tungsten Could Make Fusion Much Harder

One particularly striking finding concerns tungsten, an extremely heat-resistant metal selected for the interior walls of more than a dozen next-generation fusion machines.

Tungsten is attractive because fusion reactors must withstand conditions involving plasma temperatures greater than those found at the center of the sun. However, the material also presents a significant challenge if even tiny quantities enter the plasma.

The team’s calculations show that tungsten contamination at a concentration of just one part in 10,000 can approximately double the pressure required to achieve fusion ignition.

That is a substantial increase caused by an exceptionally small amount of material.

The calculations were initially developed in two dimensions. When the researchers extended their analysis to three dimensions, they found that the pressure needed for ignition could exceed the limits at which the plasma remains stable.

This suggests that seemingly minor contamination could have major consequences for the feasibility of certain fusion reactor designs.

How Energy Losses Could Help Stabilize Fusion

Surprisingly, some of the processes that make ignition more difficult may also help fusion reactors operate more safely and consistently.

Scientists have long investigated the possibility of thermal “runaway” instability. This occurs when heat from fusion reactions increases the reaction rate, producing still more heat and potentially creating a self-reinforcing cycle.

The researchers found that energy losses within the plasma can naturally counteract this effect.

Although those losses increase the difficulty of reaching ignition, they also provide a balancing influence that could allow a burning plasma to maintain a stable operating state without constant adjustments.

This balance could be valuable for future reactor designs.

(Unlike a fission power plant, a fusion system holds only seconds of fuel at a time, so losing control means the plasma cools and the burn stops rather than anything worse.)

Liquid Lithium and Advanced Fuel Could Improve Fusion Efficiency

The study also identifies technologies that might help overcome some of the obstacles revealed by the calculations.

One possibility involves coating the inside of fusion reactors with liquid lithium, a technique PPPL researchers have investigated for years.

These coatings could help prevent tungsten from entering the plasma while reducing heat losses, making it easier to maintain the extreme conditions necessary for fusion.

Another promising approach uses spin-polarized fuel. This involves preparing the atomic nuclei so that their spins are aligned before fusion occurs, which can increase the fusion reaction rate.

Together, these strategies could improve the performance of future reactors and make the path to ignition more achievable.

What Comes Next for the New Fusion Strategy?

Despite the promising findings, the proposed heat-first approach has not yet been demonstrated experimentally.

The research is theoretical and relies on mathematical calculations rather than direct measurements. Existing fusion experiments have not reached the temperatures associated with the Cordey saddle, preventing scientists from testing the predicted route under those conditions.

The PPPL team plans to investigate the approach further through digital experiments, using computer-based simulations to explore whether heating plasma before increasing its density can deliver the expected advantages.

If future studies confirm the calculations, the findings could provide an important foundation for designing more efficient fusion systems and help researchers make better decisions about reactor construction.

“While more study is needed, we are excited by these results, and they suggest a clear path forward for future research in this area,” said Menard.

The work was supported by the DOE Office of Science, Office of Fusion Energy Sciences, under contract DE-AC02-09CH11466. Additional support came through a 2015 Fusion Energy Sciences Early Career Award, a 2018 Diagnostic Innovation and Development award, and the 2021 and 2025 Long-Pulse Tokamak Research Programs.

Most planets, including Earth, travel around their stars in relatively stable orbits. But these peaceful arrangements can sometimes end violently. If a planet ventures too close to its host star, the star’s gravity can drag it inward and eventually engulf it.

Scientists have observed many planetary systems with stable orbits, along with a small number of stars caught rapidly swallowing their planetary companions. Now, researchers have identified something that falls between those two extremes.

In a study published October 5 in Nature Astronomy, an international team led by scientists at MIT describes a star that is slowly feeding on a brown dwarf, an object more massive than a typical planet but not massive enough to sustain the hydrogen fusion that powers ordinary stars.

The system, designated ZTF J0440+2325, lies within our Milky Way galaxy approximately 300 light-years away. It is the first observed example of a low-mass star steadily drawing material from another low-mass object.

Even more remarkably, the transfer of material appears to be happening so slowly that the star could continue feeding on its companion for hundreds of thousands of years, potentially even billions.

“When we think of stars interacting with planets or brown dwarfs, the picture is always that the star eventually swallows the other thing,” says Kevin Burdge, assistant professor of physics at MIT. “This is what will happen to the Earth when the sun becomes a red giant. But here, we’ve found an alternative: Instead of swallowing the thing up, the star can gradually eat it, for billions of years.”

The MIT research team also includes Aaron Householder, Kaitlyn Shin, Saul Rappaport, Joheen Chakraborty, and Emma Chickles. Additional collaborators contributed from Caltech, the University of Hawaii, the Instituto de Astrofísica de Canarias and Universidad de La Laguna in Spain, and the Harvard-Smithsonian Center for Astrophysics.

A Mysterious Signal That Puzzled Astronomers for Years

The first clue to this unusual stellar relationship came from the Zwicky Transient Facility (ZTF), an astronomical survey that searches for objects whose brightness changes over time.

Operating with a telescope at Palomar Observatory in California, ZTF repeatedly photographs large sections of the night sky. Its sensitive camera can detect sudden or unusual changes in light that may indicate powerful cosmic events, including exploding stars called supernovae, gamma-ray bursts, and collisions between neutron stars.

Several years ago, while examining observations collected by ZTF, Burdge noticed a particularly strange pattern.

Astronomers study changes in an object’s brightness using a graph called a light curve. For some supernovae, these graphs form a rounded, bell-like shape as the exploding star grows brighter and then gradually fades.

The signal Burdge encountered looked completely different. Instead of a smooth rise and fall, the brightness repeatedly traced something resembling a triangle.

“I remember first looking at this and thinking, stars don’t make triangular waveforms like this,” he recalls.

At the time, Burdge and his colleagues were investigating another unusual signal that turned out to originate from a system known as a “black widow binary.”

These systems contain a neutron star, the extraordinarily dense remnant of a massive star, that spins rapidly while stripping material from a much smaller companion. They are named after black widow spiders because of the way the neutron star gradually destroys its partner.

Burdge initially considered whether the repeating triangular signal might come from another black widow system. However, the observations did not match what astronomers normally expect.

In a typical black widow binary, the strong contrast between the masses of the two objects produces a distinctive motion. The smaller companion moves rapidly around the much heavier neutron star, creating detectable changes in the light reaching Earth.

But the mysterious triangular signal showed no evidence of the same pronounced motion.

“We weren’t seeing that whipping back and forth here,” Burdge says. “It didn’t make any sense. We couldn’t explain what this was.”

That discrepancy led the researchers to consider another possibility. Perhaps the system did not contain one extremely massive object paired with a much lighter companion. Instead, both objects might have relatively small masses, allowing them to orbit each other with much less dramatic motion.

“If you have less mass in the system overall, things can gently orbit each other without whipping back and forth,” Burdge says. “That was the idea. But we never had any proof. And this weird triangle just sat for years.”

A Brown Dwarf That Orbits Its Star Every 87 Minutes

Eventually, Burdge and Aaron Householder, a graduate student in MIT’s Department of Earth, Atmospheric, and Planetary Sciences, returned to the unexplained signal.

Using the original ZTF observations, they identified its source as an object roughly 300 light-years away in the Milky Way. They then directed several telescopes toward the system, ZTF J0440+2325, to investigate its properties in greater detail.

A key measurement involved determining how much the system’s objects move in response to their mutual gravitational attraction. Although the researchers detected some wobbling, it was far smaller than the motion typically associated with black widow binaries.

“That was the real clincher for this system,” Householder says. “When we measured that wobble, we found we were not seeing a black widow. This was a low-mass star that’s orbited by a brown dwarf. The wobble was too small in amplitude to be anything else.”

The observations revealed two unusually compact objects orbiting at an extremely close distance.

The central star has approximately 85 times the mass of Jupiter, while the brown dwarf weighs about 25 Jupiter masses. For comparison, the Sun is more than 1,000 times as massive as Jupiter.

The brown dwarf completes a full revolution around its host star in just 87 minutes. Its entire orbit is so small that it would fit within the diameter of the Sun.

That extraordinarily close arrangement suggested that gravity might be doing more than simply keeping the objects in orbit. The researchers suspected that the star could be actively pulling matter away from the brown dwarf.

Scientists Discover a New Form of Stellar Cannibalism

When one astronomical object draws gas or other material from another, astronomers call the process accretion.

Accretion is especially familiar in systems involving black holes and neutron stars. Although these objects can be extremely massive, their physical dimensions are relatively small. Material falling toward a black hole, for example, often forms a swirling disk around it before moving inward.

But ZTF J0440+2325 appears to work differently.

Rather than a black hole or neutron star collecting matter, an ordinary low-mass star is receiving material from a nearby brown dwarf. Because the star has a much larger physical surface than a compact object such as a black hole, the incoming material can strike it directly.

“The difference here is, the thing absorbing matter is not a tiny black hole but a star, which is relatively big in size,” Burdge explains. “So matter just pummels directly onto the surface, at very high speeds, like an asteroid hitting the Moon.”

To investigate whether this was actually happening, the researchers created computer simulations of the system.

They modeled particles originating from the brown dwarf and calculated how those particles would move under the gravitational influence of both objects. The simulations incorporated the measured properties of the star and its companion, along with the physical equations governing orbital motion.

The results supported the team’s suspicion. Material leaving the brown dwarf followed trajectories that carried it directly into the star.

“When we track those test particles, we see they indeed fall right onto the surface of the star,” Householder says. “This is the first time we’ve caught a low-mass star actively accreting from another low-mass object.”

A Cosmic Feast That Could Continue for Billions of Years

The team also estimated how quickly the brown dwarf is losing material.

According to their calculations, the star is consuming approximately one hundred-thousandth of Earth’s mass every year.

That amount may sound insignificant, but it represents an enormous quantity of material. The researchers compare it to approximately 40 million dump trucks’ worth of matter, or about 1.3 trillion one-pound burritos every second.

Despite those staggering figures, the brown dwarf is so massive that this material loss represents only a tiny portion of its total mass.

In astronomical terms, the feeding process is remarkably gradual.

Based on the properties of the system and the estimated rate of mass transfer, researchers believe the star could continue drawing matter from its companion for billions of years.

Instead of a sudden, catastrophic collision that destroys the smaller object, the star appears to be sustaining a relatively steady flow of material from its neighbor.

That realization also helped explain the strange triangular light pattern that first attracted Burdge’s attention.

As matter streams from the brown dwarf toward the star, it strikes the stellar surface at high speeds, generating an intensely heated region.

This bright hotspot acts like a persistent fireball on the star.

As the brown dwarf moves through its 87-minute orbit, the hotspot repeatedly rotates into and out of the observer’s view. Those changes in visibility produce the distinctive pattern of brightening and dimming that the astronomers had struggled to understand.

“It’s like you’ve got this continuous fireball onto one of the objects, and as one orbits the other, that hotspot comes in and out of view, and the peak of the triangle signal is when you’re looking right at the fireball,” Burdge explains.

A Strange Star System Opens a New Window Into Planetary Evolution

With the triangular signal finally explained, the researchers are now interested in identifying other stellar systems that behave in similar ways.

Until now, observations of close interactions between stars and their planetary companions have largely emphasized either stable orbits or relatively rapid engulfment events.

ZTF J0440+2325 demonstrates that another possibility exists. Under the right conditions, a small star can steadily extract matter from a nearby brown dwarf without immediately destroying it.

Finding additional examples could help astronomers determine how common this process is, how long it can persist, and what ultimately happens to objects trapped in such extraordinarily close relationships.

The discovery may also provide new insights into the evolution of planets and brown dwarfs that orbit near their host stars.

“It’s inspiring a lot of new searches on our part,” Householder says. “I think we’re going to learn a lot about a different kind of way that planets and brown dwarfs interact with their host stars.”

This research received partial support from the National Science Foundation.

Researchers at the University of Helsinki investigated this question and uncovered a striking finding: people with the same depression diagnosis can have dramatically different patterns of brain activity. In some cases, communication between brain regions was unusually strong, while in others, it was weaker than normal.

Depression is a major global health concern. According to the World Health Organization (WHO, 2025), approximately 332 million (5.2%) adults worldwide are affected. In Finland, depression is the leading individual cause of both extended sick leave and disability pensions.

Brain Study Reveals Five Distinct Depression Profiles

To investigate the biological differences associated with depression, researchers examined brain activity in 263 people diagnosed with major depressive disorder and 75 healthy participants who served as a comparison group.

The analysis revealed five distinct groups based on differences in functional connectivity, a measure of how closely activity in different brain regions is coordinated. When two regions show synchronized activity, it suggests they are working together as part of a larger brain network. However, stronger connectivity does not necessarily mean the brain is functioning better.

“What was particularly interesting was the contrasting patterns of brain activity found under the umbrella of the same depression diagnoses. In some individuals, the functional connectivity between brain regions was stronger than usual, while in others it was weaker,” says Director Satu Palva of the Neuroscience Center, University of Helsinki.

These differences were also associated with particular symptoms. Participants in one group showed especially strong connections between brain regions, along with more pronounced substance abuse problems. Another group displayed weaker connections and a greater prominence of post-traumatic stress disorder (PTSD) symptoms.

The contrasting results could help explain why earlier studies examining the brains of people with depression have sometimes reached conflicting conclusions. If researchers study different combinations of patients, they may observe very different patterns, even though everyone involved has received the same diagnosis.

The findings add to growing evidence that depression may not have a single, consistent biological signature. Instead, the condition could involve several distinct patterns of brain function.

The Five Brain Patterns Linked to Depression

The researchers classified participants with depression into five groups based on how strongly different brain areas communicated and the frequencies at which their activity was coordinated.

Each group had a characteristic pattern of brain connectivity and associated symptoms:

Group 1: Strong connectivity and severe symptoms

Participants generally showed relatively strong connections between brain regions. This profile was associated with more severe symptoms across several areas, including depression, anxiety, rumination, and reduced ability to function in daily life. Rumination refers to repeatedly dwelling on distressing thoughts, worries, or negative experiences.

Group 2: Weaker connectivity and milder depression

This group was characterized by relatively weak communication between brain regions. Compared with the other groups, participants generally experienced milder symptoms.

Group 3: Widespread weak connectivity and trauma symptoms

People in this group showed reduced connectivity across substantial portions of the brain. Symptoms associated with post-traumatic stress disorder (PTSD) were particularly prominent.

Group 4: Mixed connectivity and multiple challenges

This profile combined unusually strong connections in some brain regions with weaker connections in others. Participants tended to experience more severe depression, greater substance abuse problems, and lower overall well-being.

Group 5: The strongest connectivity and substance abuse symptoms

Participants in the fifth group had the strongest connections between brain regions of any group identified in the study. Substance abuse was a particularly prominent issue, while trauma related symptoms were less pronounced than in the other groups.

Importantly, all five groups also showed differences from the healthy participants. These distinctions extended beyond whether brain connections were strong or weak. The groups also differed in which brain regions were involved and the frequencies at which their activity was synchronized.

Together, the patterns suggest that people diagnosed with depression may experience substantially different changes in how their brain networks operate.

Measuring Brain Activity With Millisecond Precision

To capture these differences, the scientists used magnetoencephalography (MEG), a brain imaging technique that detects extremely faint magnetic fields produced by electrical activity in the brain.

Unlike methods that track slower changes associated with brain activity, MEG can follow electrical signals as they unfold over extremely short periods. This makes it particularly useful for investigating the timing and coordination of communication between brain regions.

Using MEG, the researchers recorded brain activity in all 263 participants with depression and the 75 healthy control subjects.

“MEG enabled us to monitor electrical brain activity with millisecond precision, helping us get closer to what actually happens in the brain at any given moment. Previously, depression phenotypes have been studied using methods with slower responses,” Palva notes.

This high level of temporal precision allowed the team to examine rapid changes in brain activity that might be difficult to distinguish using slower measurement techniques.

By studying these fast signals, the researchers were able to identify differences not only in the strength of connectivity but also in the frequencies at which brain regions appeared to work together.

Could Brain Activity Lead to More Personalized Depression Treatments?

The discovery raises an important possibility for the future of mental health care: treatments might eventually be selected partly according to a person’s individual pattern of brain activity.

Today, finding an effective depression treatment can involve trying different medications or therapies and evaluating how well each works. Because patients can respond differently to the same treatment, identifying the most suitable approach is not always straightforward.

Brain activity measurements could eventually provide additional information to help guide these decisions. However, the researchers emphasize that their findings are not yet ready for clinical use.

“We’re not yet at the point where brain measurements can be used to choose the right treatment for patients, but the study does show one possible route,” Palva says.

A major long-term goal is to better understand how particular symptoms relate to the way brain networks function. Connecting these biological patterns with patients’ experiences could help researchers develop more precise ways to identify and characterize depression.

Eventually, such knowledge might allow doctors to determine which therapies are most likely to help individual patients, potentially reducing the amount of trial and error involved in treatment.

For now, the five brain profiles offer a different way to understand depression. Rather than assuming that one diagnosis corresponds to one underlying pattern of brain activity, the findings suggest that depression can involve markedly different biological changes, sometimes even in opposite directions.

The research was carried out in collaboration with Aalto University and Helsinki and Uusimaa Hospital District (HUS).

High-intensity interval training (HIIT), which involves alternating short bursts of demanding exercise with easier recovery periods, may be especially helpful for older adults who want to reduce fat without sacrificing lean muscle.

In a study published in Maturitas, researchers from the University of the Sunshine Coast compared three different exercise intensities. Although participants across the groups experienced modest fat loss, HIIT stood out for its ability to reduce fat while maintaining lean tissue.

“We found that high, medium and low intensity exercises all led to modest fat loss but only HIIT retained lean muscle,” said lead author and exercise physiologist Dr. Grace Rose of the University of the Sunshine Coast.

The results highlight an important distinction in healthy aging: losing weight is not necessarily the same as improving body composition.

Six Months of Exercise Revealed a Key Difference

The Australian research team investigated how workout intensity affects body composition, meaning the proportions of fat, muscle and other tissues that make up the body.

A total of 123 healthy older adults from the Greater Brisbane region participated in the trial. Their average age was 72, and their average body mass index was approximately 26kg/m², which the researchers described as normal for adults over 65.

Participants completed three supervised gym sessions each week for six months. Each session lasted 45 minutes, and participants were assigned to high-intensity intervals, moderate-intensity exercise, or a low-intensity comparison group.

To track changes, researchers measured body composition at the beginning of the study, after three months, and again at six months. They used a specialized scanning technique that estimates fat and lean tissue throughout the body.

The findings revealed that exercise intensity made a difference.

Both high- and moderate-intensity training significantly reduced fat mass, with larger improvements than those seen in the low-intensity group. However, the two more demanding approaches differed in their effects on lean tissue.

“While moderate training reduced fat mass, it also caused a small decline in lean muscle,” Rose said.

Participants performing HIIT, meanwhile, reduced fat without experiencing the same decline in lean mass.

This could be particularly valuable later in life, when maintaining muscle becomes increasingly important for physical independence. Strong muscles help people climb stairs, get out of chairs, maintain balance, and carry out everyday activities.

One important distinction is that the scans measured lean tissue rather than muscle strength directly. Lean mass includes muscle but also other tissues and water, so changes in these measurements do not necessarily translate into equivalent changes in strength.

High-Intensity Exercise Also Reduced Abdominal Fat

The researchers found another potentially important benefit involving fat stored around the middle of the body.

“Both high and moderate intensities improved the composition of weight carried around the middle. Further analysis is needed of the low intensity results.”

The original study found improvements in visceral adipose tissue among both the high and moderate intensity groups.

Visceral fat is different from the fat that sits directly beneath the skin. It accumulates deeper in the abdomen, surrounding internal organs such as the liver and intestines.

Excessive amounts of this fat have been linked to insulin resistance, cardiovascular disease, and other metabolic problems.

According to Rose, these findings matter because body composition can influence the development and progression of chronic diseases as people age.

While body weight and body mass index provide useful general information, they do not reveal how much fat or muscle a person carries, or where that fat is stored.

Someone who loses fat while maintaining muscle may experience a more favorable change in body composition than someone who loses a similar amount of weight along with valuable lean tissue.

Still, the original researchers emphasized that the improvements were relatively small. They cautioned that the differences were not clearly clinically meaningful when compared with lower intensity exercise, particularly after accounting for measurement uncertainty.

Why HIIT May Help Aging Muscles Stay Strong

One possible explanation for HIIT’s advantage lies in the way it challenges the body.

Rather than exercising at the same pace throughout a workout, HIIT repeatedly pushes the cardiovascular system and working muscles through periods of intense effort, followed by easier activity.

University of the Sunshine Coast Associate Professor of Physiology and study co-author Mia Schaumberg explained how the training worked.

“High-intensity training in this study involved repeated short bursts, or intervals, of very hard exercise — where breathing is heavy and conversation is difficult — alternated with easier recovery periods.

“HIIT likely works better because it puts more stress on the muscles, giving the body a stronger signal to keep muscle tissue rather than lose it.”

This explanation is consistent with the idea that muscles adapt to the demands placed on them. When exercise provides a sufficiently challenging stimulus, the body has more reason to maintain the tissues needed to perform that activity.

Muscle preservation is especially important because aging is often accompanied by a gradual decline in muscle mass and strength. In more advanced cases, this can contribute to sarcopenia, a condition characterized by reduced muscle strength and quantity that can interfere with mobility and independence.

Schaumberg said the original research could help people make more informed decisions about exercise and healthy aging.

When the university publicized the findings in early 2026, she also highlighted their relevance to people setting fitness goals.

“With the festive season now behind most of us and New Year’s resolutions in full swing, this research can help inform people’s plans for healthy aging in 2026,” she said.

The research involved collaborators from UniSC’s Healthy Ageing Research Cluster and The University of Queensland.

More Recent Studies Reveal Additional Benefits of HIIT

Research published in 2026 has provided further insight into how HIIT affects older adults, although it also suggests that intense workouts are not necessarily superior in every situation.

One 2026 study, published in Medicine & Science in Sports & Exercise, investigated whether older adults could benefit from completing HIIT at home with remote supervision.

The study involved 20 adults aged 61 to 74 who exercised using a specialized machine that let them work their arms and legs without bearing their body weight.

After eight weeks of training, participants had lost an average of approximately 1.4 kilograms, or about 3 pounds, of fat mass. Their aerobic fitness also improved substantially.

Participants completed 96 percent of their scheduled workouts, and the researchers reported no exercise-related adverse events.

Although the trial was small, its findings suggest that appropriately supervised HIIT programs may offer benefits outside a conventional gym.

Another 2026 randomized trial, published in The Journals of Gerontology, Series A: Biological Sciences and Medical Sciences, compared HIIT with continuous moderate-intensity exercise in older adults living with HIV.

In that study, participants completed 16 weeks of exercise, with both groups also performing resistance training.

Unlike the original Australian study, both exercise groups experienced reductions in fat and increases in lean mass. The researchers found no statistically significant difference between the two groups in those body composition changes.

These results suggest that workout intensity is not the only factor that matters. Resistance training, which challenges muscles through weights or other forms of resistance, may also help preserve or increase lean tissue.

The populations and training programs differed, so the findings should not be treated as a direct contradiction of the Australian results.

Is HIIT Really the Best Exercise for Older Adults?

A broader scientific review published in the Journal of Clinical Medicine in August 2026 offers additional perspective.

Researchers examined 25 reports involving approximately 2,818 participants to assess how HIIT and other forms of interval training affect older adults.

The most consistent benefits involved cardiovascular fitness, including improvements in the body’s ability to use oxygen during exercise.

Some studies also reported improvements in physical function and metabolic health. However, the review did not establish that HIIT was consistently better than moderate-intensity exercise.

The researchers noted that differences between exercise programs, participant characteristics, and study methods made it difficult to identify a single optimal training approach.

Taken together, the findings suggest that HIIT can be a useful tool for healthy aging, but it is not the only way to improve fitness or protect muscle.

For adults over 65, the Centers for Disease Control and Prevention recommends a combination of aerobic exercise, muscle strengthening activities, and exercises that improve balance.

Higher intensity workouts may be appropriate for some older adults, but people who are inactive or have medical conditions may benefit from gradually building up their fitness and seeking guidance before beginning a demanding program.

The central message from the Australian study remains compelling: what happens to muscle during fat loss may be just as important as the amount of weight someone loses.

HIIT showed promise because it helped participants reduce body fat while maintaining lean tissue. Combined with newer findings, the research reinforces the value of exercise programs that support not just a lower number on the scale, but also the strength, fitness, and physical function needed for healthy aging.

The four astronauts spent 237 days in orbit, traveled more than 100 million miles, and completed thousands of trips around Earth while carrying out scientific experiments that could help shape future missions to the Moon and Mars.

NASA will host a news conference at 3:30 p.m. EDT on Thursday, Oct. 15, at Johnson Space Center in Houston, where returning crew members will discuss their experiences and research accomplishments.

“Jessica, Jack, Sophie, and Andrey spent 237 days living and working in orbit, traveled more than 100 million miles, advanced important science, and returned safely home because of the extraordinary expertise and competence of thousands across NASA, SpaceX, and our international partners,” said NASA Administrator Jared Isaacman. “Building the capability, experience, and confidence to do this repeatedly is exactly what will allow us to go farther, and I am grateful to Crew-12 and their families for their service to humanity’s greatest adventure.”

NASA Astronauts Return After 237 Days and 100 Million Miles

The returning crew included NASA astronauts Jessica Meir and Jack Hathaway, ESA (European Space Agency) astronaut Sophie Adenot, and Roscosmos cosmonaut Andrey Fedyaev.

Their spacecraft touched down in the Pacific at 8:34 a.m. PDT. SpaceX recovery teams aboard specialized vessels reached the capsule shortly afterward and brought the astronauts and spacecraft aboard.

Following routine medical evaluations, the crew members will be transported to shore before traveling to NASA’s Johnson Space Center in Houston.

“NASA’s activities supporting the International Space Station — transporting crew, conducting impactful research, and maintaining critical national assets — enable the science, engineering, and risk‑reduction needed for future missions across the solar system,” said Dana Weigel, manager of NASA’s Low Earth Orbit Program at the agency’s Johnson Space Center. “We’re grateful for the dedication across the human spaceflight team that makes this possible, and we’re thrilled to welcome Jessica, Jack, Sophie, and Andrey home.”

Over the course of their 237-day stay, the astronauts circled Earth more than 3,792 times, accumulating over 100 million miles of travel.

For Meir and Fedyaev, Crew-12 marked their second journey into space. Hathaway and Adenot, meanwhile, completed their first space missions.

The crew launched on Feb. 13 at 5:15 a.m. EST, reaching and docking with the International Space Station the following day.

Space Station Experiments Could Help Future Moon and Mars Missions

Beyond the remarkable distance traveled, Crew-12 devoted hundreds of hours to scientific investigations designed to support future human exploration and improve life on Earth.

One research project explored ways to produce stem cells in space for potential use in cell-based medical treatments. Another demonstrated technology capable of producing IV fluids on demand, an ability that could become especially valuable during long-duration missions far from Earth.

The astronauts also investigated how pneumonia-causing bacteria may contribute to lasting heart damage. Understanding this relationship could offer new insights into cardiovascular health.

Other experiments focused on nutrition in space and how individual physical characteristics may influence blood flow during spaceflight. These studies could help researchers better understand the health risks astronauts face during extended stays in microgravity.

Together, the investigations provide valuable information about keeping humans healthy beyond Earth while testing technologies that may eventually support crewed expeditions to the Moon and Mars.

Historic Spacewalks Mark Crew-12 Mission

The mission also included significant milestones outside the space station.

Meir carried out four spacewalks during Crew-12, raising her career total to seven. That achievement places her third among NASA women for the most career spacewalks, behind former astronauts Peggy Whitson and Suni Williams.

Adenot also reached a historic milestone by completing three spacewalks. In doing so, she became the first French woman to venture outside the International Space Station.

With Crew-12 safely back on Earth, NASA has completed another extended mission that combined scientific research, international cooperation, and human spaceflight experience. The knowledge gained will contribute to preparations for more ambitious journeys beyond Earth’s orbit.

NASA has highlighted four events worth watching this month, ranging from Jupiter briefly vanishing behind the Moon to shooting stars created by debris from Halley’s Comet. With crisp autumn evenings and a little luck, skywatchers can enjoy several of these displays without any special equipment.

Jupiter Disappears Behind the Moon on October 6

Before sunrise on Tuesday, October 6, skywatchers in parts of North America had an opportunity to witness an unusual celestial disappearing act. Jupiter, the largest planet in our solar system, slipped behind the Moon’s slender crescent and remained hidden for approximately an hour before coming back into view.

Astronomers call this phenomenon a lunar occultation. It happens when the Moon moves directly between Earth and a more distant object, temporarily blocking our view. Despite its mysterious-sounding name, occultation simply refers to one celestial object concealing another.

The event was visible to the naked eye, although binoculars offered a more detailed look. Observers using optical equipment could also potentially watch some of Jupiter’s moons disappear behind the lunar edge and emerge again.

Viewing opportunities depended on location, with the occultation visible across parts of eastern and central North America. The timing varied geographically, with the event occurring during the early morning hours, around 4 a.m. EDT in some locations.

Draconid Meteor Shower Peaks October 8 and 9

The next celestial attraction comes on the evening of Thursday, October 8, when the Draconid meteor shower reaches its peak. Favorable viewing beginning around 9 p.m. EDT, and the display continues into the early hours of Friday, October 9.

Unlike many meteor showers that are best observed after midnight, the Draconids offer a convenient opportunity to see shooting stars soon after nightfall. That makes them particularly appealing to casual observers who would rather not stay awake until dawn.

Conditions are especially promising this year because the Moon is approaching its new phase. With little moonlight to brighten the sky, even relatively faint meteors should be easier to detect.

The shower gets its name from Draco, a constellation representing a dragon. Although the name might sound like something from a Halloween horror story involving a certain famous vampire, it actually refers to the constellation from which the meteors appear to originate.

The Draconids are generally a modest display, typically producing only a handful of visible meteors each hour. For the best chance of spotting them, head somewhere away from bright city lights, allow your eyes to adjust to the darkness, and scan the open sky for brief streaks of light.

Orionid Meteor Shower Brings Debris From Halley’s Comet

Another opportunity to catch shooting stars arrives on October 21, when the Orionid meteor shower reaches its annual peak.

These meteors have a particularly fascinating origin. They are tiny fragments of material left behind by Halley’s Comet during its journeys through the solar system. When Earth travels through this trail of ancient comet debris, the particles enter our atmosphere at tremendous speeds, creating bright streaks of light as they burn up.

For observers in suburban areas with some artificial lighting, NASA estimates that approximately 3 to 6 meteors may be visible each hour. People watching from darker locations could see somewhat more.

The Orionids take their name from Orion, the famous hunter constellation, because their meteors appear to radiate from that region of the sky. Orion is also home to Betelgeuse, an enormous red supergiant star recognizable by its reddish appearance (but don’t say that name three times in a row!).

There is one potential obstacle to this year’s display. The Moon will be in its waxing gibbous phase, meaning more than half of its visible surface will be illuminated. Its brightness could make some of the dimmer meteors difficult to spot.

Fortunately, viewing conditions should improve after the Moon sets at approximately 3 a.m. local time. By then, Orion will also be higher in the sky, creating a better opportunity to catch meteors during the hours before sunrise.

October’s Hunter’s Moon Lights Up the Halloween Sky

October’s final major celestial highlight is the Hunter’s Moon, which reaches its full phase on October 26 in Universal Time. For observers in much of North America, the Moon will appear full on the evening of Sunday, October 25.

The name Hunter’s Moon comes from traditions associated with the changing autumn season. As crops were harvested, fields became more open, and daylight hours shortened, hunters could take advantage of the bright moonlight to locate and follow animals after sunset.

The Moon will remain a prominent feature of the night sky in the days following its full phase. As Halloween approaches, it will gradually transition into a waning gibbous Moon, with its illuminated portion slowly decreasing each night.

Its lingering glow will provide a fitting backdrop for the final evenings of October, bringing NASA’s month of celestial tricks and treats to a memorable close.