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Sunday, February 01, 2026
Saturday, January 31, 2026
SPACE/COSMOS
New map of the Milky Way’s magnetism offers insights into cosmic evolution
UBCO-led DRAGONS project charts radio wave twists across the northern sky
University of British Columbia Okanagan campus
image:
The DRAO 15m telescope at work scanning the sky for the DRAGONS survey. The data collected by this survey is a new generation of radio surveys that allow scientists to continue mapping the Milky Way and its three-dimensional magnetic field structure.
view moreCredit: Luca Galler
A UBC Okanagan-led research project has given a group of international scientists their clearest view yet of the Milky Way’s magnetic field, revealing that it is far more complex than previously believed.
Dr. Alex Hill, Assistant Professor in the Irving K. Barber Faculty of Science at UBCO, specializes in radio astronomy. Working at the Dominion Radio Astrophysical Observatory (DRAO), near Penticton, his team used data from the DRAO 15-metre telescope to complete the first broadband map of Faraday rotation, a phenomenon that scientists use to track magnetic fields across the northern sky.
The dataset, known as Dominion Radio Astrophysical Observatory GMIMS of the northern sky (DRAGONS) and led by former UBCO postdoctoral researcher Dr. Anna Ordog, captures polarized radio emissions across a wide range of frequencies, allowing astronomers to see magnetic structures that were previously invisible. This research is part of a larger initiative called the Global Magneto-Ionic Medium Survey (GMIMS), initiated by Dr. Tom Landecker, an astronomer at DRAO and adjunct professor at both UBCO and the University of Calgary.
“With our new dataset, we can look at the polarized emissions from within the galaxy itself, and we see that the magnetic field has a lot of structure to it,” Dr. Ordog explains. “DRAGONS is the first to show this level of complexity on such large spatial scales and across the entire northern sky.”
The work builds on a theoretical insight first proposed in 1966, which showed that polarized radio waves observed at many frequencies enable measurements of the three-dimensional structure of the Milky Way’s magnetic field. At the time, the technology needed to observe this effect across wide frequency ranges did not exist. Modern broadband telescopes, including the DRAO 15m telescope, have made this research possible.
The project was the first scientific use of the 15m telescope, which DRAO originally built as a prototype antenna for the SKA—a large radio telescope currently under construction in Southern Africa and Western Australia. Dr. Ordog led the setup for the DRAGONS project, supported by five students from UBCO and the University of Calgary, along with the expertise of DRAO engineers and technologists.
“The 15m is the ideal instrument for this all-sky survey of large-scale magnetized structures—it can scan rapidly, effectively ‘painting’ a map of the polarized sky in just six months,” she says. “Having the 15m so close to UBCO allowed students to contribute to hands-on testing in preparation for the survey.”
UBCO students analyzed “first light” signals from the instrument, developed algorithms to identify human-made radio interference and assessed the survey data quality.
The study, recently published in The Astrophysical Journal Supplement Series, tracks how polarized radio waves twist as they travel through the galaxy, revealing the strength, structure and direction of magnetic fields along the line of sight. This survey shows that more than half the sky contains complex magnetic structures rather than simple, uniform fields.
Dr. Landecker says the biggest surprise for the researchers was just how much of the sky is what is known as “Faraday complex”.
“With our new dataset, we can look at the polarized emission from within the galaxy itself, and we can see that the magnetic field has much more structure to it than we could detect with earlier observation methods,” says Dr. Landecker, who is also the leader of a larger effort to map magnetic fields in three dimensions and an astronomer emeritus at DRAO.
“DRAGONS is like a compass, telling us how matter and magnetic fields in the galaxy are organized and how the magnetic field interacts with bubbles created by supernova explosions, spiral arms and other parts of the galaxy in ways that have never been possible before.”
Magnetic fields shape how stars are formed and how galaxies evolve, explains Dr. Hill.
“For decades, we could only measure the Milky Way’s magnetic field in a very averaged, simplified way,” says Dr. Hill. “But its magnetic field is an important piece of the puzzle when it comes to understanding how the universe and everything in it operates and came into being.”
Already, the DRAGONS data have been used in a study of the mysterious large-scale reversal in the galactic magnetic field. This latest study was led by University of Calgary doctoral student Rebecca Booth and published in an accompanying paper in The Astrophysical Journal this week. This is a good example of how the dataset will provide opportunities for continued research in this field, says Dr. Ordog.
“DRAGONS is part of a new generation of radio surveys that allow scientists to map the Milky Way’s three-dimensional magnetic field structure in the space between the stars,” she adds. “It is an important Canadian contribution to the global astronomical community.”
Journal
The Astrophysical Journal Supplement Series
Method of Research
Observational study
Subject of Research
Not applicable
Article Title
GMIMS-DRAGONS: A Faraday Depth Survey of the Northern Sky Covering 350–1030 MHz
Article Publication Date
29-Jan-2026
Mapping the magnetic field of the Milky Way
Two new studies reveal structural complexity in the galaxy
Peer-Reviewed PublicationFor centuries, astronomers have been observing celestial bodies and trying to understand the mysteries of the night sky. Dr. Jo-Anne Brown, PhD, wants to map an invisible force of the Milky Way galaxy: its magnetic field.
“Without a magnetic field, the galaxy would collapse in on itself due to gravity,” says Brown, a professor in the Department of Physics and Astronomy at the University of Calgary.
“We need to know what the magnetic field of the galaxy looks like now, so we can create accurate models that predict how it will evolve.”
This month, Brown and a team of researchers have published two papers in The Astrophysical Journal and The Astrophysical Journal Supplement Series. Their discoveries include a complete dataset, which will be used by astronomers globally, and a new model that will inform theories for how the magnetic field of the Milky Way evolved.
The group used a new telescope at the Dominion Radio Astrophysical Observatory in B.C., a National Research Council Canada facility, to map the northern sky across different radio frequencies.
“The broad coverage really lets you get at the details about the magnetic field structure,” says Dr. Anna Ordog, PhD, and lead author of the first of the two studies.
The result is a comprehensive, high-quality dataset, captured as part of the Global Magneto-Ionic Medium Survey (GMIMS) project that maps the magnetic field of the Milky Way galaxy.
The data that was collected involved tracking an effect known as Faraday rotation.
“You can think of it like refraction. A straw in a glass of water looks bent because of how light interacts with matter,” says Rebecca Booth, a PhD candidate working with Brown and lead author of the second study. “Faraday rotation is a similar concept, but it’s electrons and magnetic fields in space interacting with radio waves.”
Booth’s work in the second study looked at a unique feature in the Milky Way galaxy — the Sagittarius Arm, which has a reversed magnetic field.
“If you could look at the galaxy from above, the overall magnetic field is going clockwise,” says Brown. “But, in the Sagittarius Arm, it’s going counterclockwise. We didn’t understand how the transition occurred. Then one day, Anna brought in some data, and I went, 'O.M.G., the reversal's diagonal!'"
Booth followed up on Ordog's discovery using the dataset.
“My work presents a new three-dimensional model for the magnetic field reversal. From Earth, this would appear as the diagonal that we observe in the data,” Booth explains.
Journal
The Astrophysical Journal
Method of Research
Survey
Subject of Research
Not applicable
Article Title
A Three-dimensional Model for the Reversal in the Local Large-scale Interstellar Magnetic Field
Article Publication Date
29-Jan-2026
Why are Tatooine planets rare? Blame general relativity
Physicists explain the dearth of exoplanets around tight binary stars
University of California - Berkeley
image:
A step-by-step explanation for why planets that orbit a double star eventually enter an unstable orbit and disappear from the system.
view moreCredit: Mohammad Farhat/UC Berkeley
Of the more than 4,500 stars known to have planets, one puzzling statistic stands out. Even though nearly all stars are expected to have planets and most stars form in pairs, planets that orbit both stars in a pair are rare.
Of the more than 6,000 extrasolar planets, or exoplanets, confirmed to date — most of them found by NASA’s Kepler Space Telescope and the Transiting Exoplanet Survey Satellite (TESS) — only 14 are observed to orbit binary stars. There should be hundreds. Where are all the planets with two suns, like Tatooine in Star Wars?
Astrophysicists at the University of California, Berkeley, and the American University of Beirut have now proposed a reason for this dearth of circumbinary exoplanets — and Einstein’s general theory of relativity is to blame.
In most binary star systems, the stars have similar but not identical masses and orbit one another in an egg-shaped or elliptical orbit. If a planet is orbiting the pair of stars, the gravitational tugs from the stars make the planet’s orbit precess, meaning the orbital axis rotates similar to the way the axis of a spinning top rotates or precesses in Earth’s gravity.
The orbit of the binary stars also precesses, but mainly because of general relativity. Over time, tidal interactions between the binary pair shrink the orbit, which has two effects: The precession rate of the stars increases, but the precession rate of the planet slows. When the two precession rates match, or resonate, the planet’s orbit becomes wildly elongated, taking it farther from the star but also nearer at its closest approach.
“Two things can happen: Either the planet gets very, very close to the binary, suffering tidal disruption or being engulfed by one of the stars, or its orbit gets significantly perturbed by the binary to be eventually ejected from the system,” said Mohammad Farhat, a Miller Postdoctoral Fellow at UC Berkeley and first author of the paper. “In both cases, you get rid of the planet.”
That doesn’t mean that binary stars don’t have planets, he cautioned. But the only ones that survive this process are too far from the stars for us to detect with transit techniques used by Kepler and TESS.
“There are surely planets out there. It’s just that they are difficult to detect with current instruments,” said co-author Jihad Touma, a physics professor at the American University of Beirut.
They published their findings Dec. 8 in The Astrophysical Journal Letters.
‘An absolute desert’
Both the Kepler and TESS missions searched for exoplanets by looking for a slight dimming of a star as a planet crossed in front of it. But Kepler also found about 3,000 eclipsing binary stars, as one of the pair of stars passed in front of the other. Since about 10% of single sun-like stars were found to have massive planets, astronomers expected to see large planets around about 10% of binaries also — or some 300 stars. Instead, only 47 candidate planets around binary stars were found, and only 14 have been confirmed as transiting circumbinary planets.
None of these 14 exoplanets occur around tight binaries orbiting one another in less than about seven days.
“You have a scarcity of circumbinary planets in general and you have an absolute desert around binaries with orbital periods of seven days or less,” Farhat said. “The overwhelming majority of eclipsing binaries are tight binaries and are precisely the systems around which we most expect to find transiting circumbinary planets.”
Farhat points out that binaries have an instability zone around them in which no planet can survive. Within that zone, the three-body interactions between the two stars and the planet either expel the planet from the system or pull it close enough to merge with or be shredded by the stars. Peculiarly, 12 of the 14 known transiting exoplanets around tight binaries are just beyond the edge of the instability zone, where they apparently migrated from farther away, since planets would have a hard time forming there.
“Planets form from the bottom up, by sticking small-scale planetesimals together. But forming a planet at the edge of the instability zone would be like trying to stick snowflakes together in a hurricane,” he said.
Farhat had previously collaborated with Touma on the formation and evolution of planetary orbits in various star systems, including our own. But Touma also had an interest in the orbits of binary black holes and binary stars. He realized 10 years ago that general relativity should change how planets move around double-star systems, but he didn’t know if the effect was strong enough to matter. After digging deeper into exoplanets, however, he suggested that the subtle pushes and pulls from relativity—combined with the stars slowly spiraling closer together—might explain the mystery of the missing planets around tight binaries.
Using mathematical and computer models, Farhat and Touma found that general relativity had a dramatic effect on the fates of circumbinary planets, effectively clearing out any close-in planets. Based on their calculations, general relativistic effects would disrupt eight of every 10 exoplanets around tight binaries, and of those, 75% would be destroyed in the process.
The precession of Mercury’s orbit
Proposed by Albert Einstein in 1915, the general theory of relativity interprets gravity as a warping of the fabric of spacetime by a mass, analogous to how a person on a trampoline warps the surface and makes other objects on the trampoline fall inward. Mercury’s orbit happens to be closest to the gravitational warp of the sun and, as a result, experiences an orbital precession slightly higher than predicted by the earlier theory of gravity laid out by Isaac Newton. The general relativistic explanation for the additional precession of Mercury’s orbit more than a century ago was the first confirmation of Einstein’s theory.
The same effect comes into play when any two objects get close to one another, such as tight-knit binary stars. Binary stars likely begin their lives far apart, but as they interact with surrounding gas during the formation of their star system, it’s predicted that many pairs will move closer together over tens of millions of years. When they do, they generate tides in one another that slowly, over billions of years, shrink the orbit even more. Eventually, as they tighten to periods of around a week or less, general-relativistic precession becomes increasingly important. This makes the orbit precess, which means that the point of closest approach, or periastron, also rotates. As the stars get closer and closer, the rate of precession increases.
A circumbinary exoplanet also sees its elliptical axis precess, in this case because of the gravitational tug of the two stars — a strictly Newtonian process. However, as the binaries move closer to one another, their perturbation of the planet gradually weakens and the precession slows down.
As the orbital precession of the binary stars increases and that of the exoplanet decreases, at some point they match and enter a state of resonance. At this point, calculations show, the exoplanet’s orbit starts to elongate, taking it farther from the binary at the extreme point of its orbit but closer at periastron. When periastron enters the zone of instability, the exoplanet is either exiled to the far reaches of the system or approaches too close to the binary and is engulfed. Because this disruption occurs quickly, taking a few tens of millions of years within the multibillion-year lifetime of a star, exoplanets around tight binaries end up being very rare.
“A planet caught in resonance finds its orbit deformed to higher and higher eccentricities, precessing faster and faster while staying in tune with the orbit of the binary, which is shrinking,” Touma said. “And on the route, it encounters that instability zone around binaries, where three-body effects kick into place and gravitationally clear out the zone.”
“Just the natural way you form these tight binaries, these sub-seven-day binaries, you get rid of the planet naturally, without invoking additional disruption from a nearby star or other mechanisms,” Farhat said.
According to Touma, the same processes are likely to sweep multiple planets out of binary systems — especially those detectable by Kepler or TESS.
The researchers are employing their models to determine how general relativistic effects impact clusters of stars around pairs of supermassive black holes, and whether, in a more speculative vein, general relativity can partially explain the dearth of planets around binary pulsars — two spinning neutron stars in orbit around one another and emitting precisely timed radio pulses. This work illustrates the major role played by Einstein’s revolutionary theory of gravity even in simple systems where Newton’s gravitational laws were thought to explain everything.
“Interestingly enough, nearly a century following Einstein’s calculations, computer simulations showed how relativistic effects may have saved Mercury from chaotic diffusion out of the solar system. Here we see related effects at work disrupting planetary systems,” Touma said. “General relativity is stabilizing systems in some ways and disturbing them in other ways.”
Farhat is supported by the Miller Institute for Basic Research in Science at UC Berkeley.
Journal
The Astrophysical Journal Letters
Article Title
Capture into Apsidal Resonance and the Decimation of Planets around Inspiraling Binaries
Kissing the sun: Unraveling mysteries of the solar wind
A University of Arizona-led research team has measured the dynamics and ever-changing "shell" of hot gas from where the solar wind originates.
University of Arizona
image:
This artist’s concept depicts the boundary of the sun’s atmosphere that marks the point of no return for material that escapes the sun’s magnetic grasp. Deep dives through this area using NASA’s Parker Solar Probe combined with solar wind measurements from other spacecraft have allowed scientists to track the evolution of this structure throughout the solar cycle and produce a map of this previously uncharted boundary.
view moreCredit: CfA/Melissa Weiss
Using data collected by NASA's Parker Solar Probe during its closest approach to the sun, a University of Arizona-led research team has measured the dynamics and ever-changing "shell" of hot gas from where the solar wind originates.
Published in Geophysical Research Letters, the findings not only help scientists answer fundamental questions about energy and matter moving through the heliosphere – the volume of space controlled by the sun's activity – which affects not just the Earth and moon, but all planets in the solar system, reaching far into interstellar space. These effects include significant space weather events.
"One of the things that we care about as a technologically advancing society is how we are impacted by the sun, the star that we live with," said Kristopher Klein, associate professor in the U of A Lunar and Planetary Laboratory who led the research study.
For example, during a coronal mass ejection, the sun flings chunks of its atmosphere – highly energetic, charged particles – out into the solar system, where they interact with Earth's magnetic field, with varying impacts on satellites, radio communications and even the radiation airplane passengers are exposed to when they fly over the poles, Klein explained.
"If we can better understand the sun's atmosphere through which these energetic particles are moving, it improves our ability to forecast how these eruptions from the sun will actually propagate through the solar system and eventually hit and possibly impact the Earth," he said.
While the idea of the sun having an atmosphere may seem difficult to imagine, since our star is essentially a roiling ball of plasma – hot, ionized hydrogen gas – with no appreciable surface, a century of studying its properties has led to a more nuanced picture. The core, where hydrogen undergoes nuclear fusion into helium, is the furnace driving the sun's activity, causing it to constantly radiate energy out into space.
Several layers wrap around the core, with the outermost ones forming the sun's atmosphere. The photosphere, where sunspots are located, is surrounded by a thin "peel" known as the chromosphere, from which flares may sprout and that forms the blotchy "surface" one may see when looking at the sun through a telescope equipped with special filters to allow for safe viewing. The sun's outermost atmospheric layer, the corona, is a fuzzy halo of plasma hidden from view at all times by the star's intense brilliance except for brief moments during a total solar eclipse.
Launched in 2018, Parker Solar Probe has approached the sun closer than any spacecraft mission before. Orbiting the sun in a complex orbit, involving seven passes by Venus, the probe reached its first closest approach on Christmas Eve 2024, and these close approaches have allowed the science team to map the sun's "outer boundary" in a way not possible until now.
In a counterintuitive twist, as the plasma bubbles up from the sun's core, it cools from 27 million degrees to about 10,000 degrees Fahrenheit in the visible photosphere, but as it fans out into the corona, it heats up again, to temperatures in excess of 2 million degrees.
The processes driving these strange dynamics involve complex interactions of the sun's charged particles with powerful magnetic fields that bend, twist and even snap back on themselves – with poorly understood details that have vexed heliophysicists to this day.
"We know there's this constant heat that's being input into the solar wind, and we want to understand what mechanisms are actually leading to that heating," Klein said. "We have made simplified models, we've run computer simulations, but by launching Parker Solar Probe, and by doing these detailed calculations of the structure of the velocity distribution of the particles, we can improve those models and calculate actually how the heating occurs at these at these extremely close distances where we have never measured before."
Before sending a robotic spacecraft capable of "kissing the sun," as the Parker team has referred to the probe's closest flyby, taking it to within 3.8 million miles above the sun's surface, researchers could only describe this heating using simple models for the charged particle distributions.
"One of the pressing questions we seek to answer is how the solar wind is heated as it is accelerated from the sun's surface," he said. "With these new measurements and calculations, we're rewriting our understanding of how energy moves through the sun's outer atmosphere."
A numerical code developed by Klein's team, dubbed Arbitrary Linear Plasma Solver, or ALPS, allowed the researchers to analyze the actual measured distribution rather than using a simplified model to determine how waves move through the plasma Parker is measuring, and – importantly – how the heating changes as the particles hurtle away from the sun. At the point of no return, where the solar wind is born, they begin to cool, but much more slowly than would be expected for a gas that is simply expanding, Klein explained – a process known as damping and yet another mystery waiting to be fully understood.
With ALPS and Parker's observations, the team can measure in detail how much energy is imparted onto the different species of charged particles in the solar wind, said Klein, explaining that this ability changes researchers' understanding of that process not just for the sun, but for all astrophysical objects involving heated plasma and magnetic fields.
"If we can understand the damping in the solar wind, we can then apply that knowledge of energy dissipation to things like interstellar gas, accretion disks around black holes, neutron stars and other astrophysical objects."
When taking the measurements for this study, the Parker Solar Probe, pictured here in an artist's impression, traveled at more than 427,000 miles per hour, making it the fastest human-made object in history.
Credit
NASA/APL
Journal
Geophysical Research Letters
Method of Research
Data/statistical analysis
Subject of Research
Not applicable
Article Title
Ion-Scale Wave Emission and Absorption for Non-Maxwellian Velocity Distributions in the Inner Heliosphere
Article Publication Date
29-Jan-2026
By AFP
January 30, 2026
NASA is preparing to conduct key tests before its Moon rocket can blast off from Florida - Copyright AFP Miguel J. Rodriguez Carrillo
NASA on Friday pushed back the earliest date that astronauts could fly to the Moon, due to forecasts of freezing temperatures at the Florida launch site.
The earliest window for the moonshot will now be February 8, two days later than originally scheduled.
NASA was preparing to conduct a key fueling test over the weekend of the 322-foot (98-meter) rocket that is on the Cape Canaveral launch pad in Florida.
But large parts of the United States are grappling with severe winter weather, with Arctic air surging across the country following a deadly winter storm.
Florida is not immune: the normally sunny state could experience its lowest temperatures in decades that are forecast to hover around freezing.
“The expected weather this weekend would violate launch conditions,” NASA said in a statement.
Weather permitting, NASA crews now are aiming to conduct their final tests Monday, after which a launch date will be determined.
The change narrows the possibility that NASA can launch their Artemis 2 team of four astronauts on their Moon flyby in February — just three days of potential windows remain in that month.
The team remains in quarantine in Houston, NASA said.
Heaters are atop the Orion capsule to ensure it stays warm, the US space agency said, and purging systems are in place and configured for the colder weather to maintain proper conditions.
NASA officials are also preparing to launch a crew to the International Space Station, a mission that is being closely coordinated as it is currently planned to happen within days of a potential Artemis 2 launch.
The next NASA crew rotation to the ISS could happen as soon as February 11, but depending on the Artemis plans, it could get delayed.
“Our teams have worked very carefully to see how we can keep moving towards launch for both missions, while at the same time making sure we avoid any major conflicts,” said Ken Bowersox, an administrator at NASA’s Space Operations Mission Directorate, during a briefing Friday.
There’s a possibility that Crew-12 could get some overlapping space time with the Moon team, a prospect that ISS astronauts said Friday they’d enjoy.
“If we do launch before Artemis, we’ll be on board the International Space Station, and part of their flight plan actually involves a call to the ISS,” said Jessica Meir, the crew’s commander who said they’d be “excited” to have some intra-space conversation with their colleagues.
“We are all thrilled about the launch of Artemis. We are very excited to see how this will all play out.”
The Crew-12 team to ISS also includes Sophie Adenot, who will be the second Frenchwoman to fly to space.
In another noteworthy tidbit, the new February 8 window for a potential launch to the Moon falls on the same day as the highly watched Super Bowl, the National Football League championship.
That launch window would open at 11:20 pm in Florida (0420 GMT on February 9) — soon after the game would likely wrap.
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