SPACE/COSMOS
Astronomers challenge 50-year-old quasar law
image:
An artist’s impression of a bright quasar almost outshining its host galaxy.
view moreCredit: Dimitrios Sakkas (tomakti), Antonis Georgakakis, Angel Ruiz, Maria Chira (NOA)
Royal Astronomical Society press release
Compelling evidence that the structure of matter surrounding supermassive black holes has changed over cosmic time has been uncovered by an international team of astronomers.
If true, the research led by the National Observatory of Athens and published today in Monthly Notices of the Royal Astronomical Society would challenge a fundamental law which has existed for almost five decades.
Quasars – first identified in the 1960s – are some of the brightest objects in the universe. They are powered by supermassive black holes as matter, pulled by strong gravity, spirals inwards, forming a rotating disc-like structure which eventually plunges into the black hole.
This disc is extremely hot because of the friction between matter particles as they revolve around the black hole. It produces 100 to 1,000 times as much light as an entire galaxy containing 100 billion stars, generating a glow that outshines its host galaxy and everything in it. This vast amount of ultraviolet light can be observed by telescopes, allowing astronomers to find quasars at the edge of the universe.
The ultraviolet light of the disc is also believed to be the fuel for the much more energetic X-ray light produced by quasars: the ultraviolet light rays as they travel through space intercept clouds of highly energetic particles very close to the black hole, a structure also known as the “corona”.
As they bounce off these energetic particles, the ultraviolet rays are boosted in energy and generate intense X-ray light that our detectors can also spot.
Because of their shared history, the X-ray and ultraviolet emissions of quasars are tightly connected – brighter ultraviolet light typically means stronger X-ray intensity. This correlation, discovered nearly 50 years ago, provides fundamental insights into the geometry and physical conditions of the material close to supermassive black holes and has been the focus of intense research for decades.
The latest research adds a new twist to previous studies by challenging the universality of the correlation – a fundamental assumption that implies that the structure of matter around black holes is similar throughout the universe.
It shows that when the universe was younger – about half its present age – the correlation between the X-ray and ultraviolet light of quasars was significantly different from that observed in the nearby universe. The discovery suggests that the physical processes linking the accretion disc and the corona around supermassive black holes may have changed over the last 6.5 billions of years of cosmic history.
“Confirming a non-universal X-ray-to-ultraviolet relation with cosmic time is quite surprising and challenges our understanding of how supermassive black holes grow and radiate,” said Dr Antonis Georgakakis, one of the study’s authors.
“We tested the result using different approaches, but it appears to be persistent.”
The study combines new X-ray observations from eROSITA X-ray telescope and archival data from the XMM-Newton X-ray observatory of the European Space Agency to explore the relation between X-ray and ultraviolet light intensity of an unprecedentedly large sample of quasars. The new eROSITA’s wide and uniform X-ray coverage proved decisive, enabling the team to study quasar populations on a scale never before possible.
The universality of the UV-to-X-ray relation underpins certain methods that use quasars as "standard candles" to measure the geometry of the universe and ultimately probe the nature of dark matter and dark energy. This new result highlights the necessity for caution, demonstrating that the assumption of unchanging black hole structure across cosmic time must be rigorously re-examined.
“The key advance here is methodological,” said postdoctoral researcher Maria Chira, of the National Observatory of Athens, who is the paper’s lead author.
“The eROSITA survey is vast but relatively shallow – many quasars are detected with only a few X-ray photons. By combining these data in a robust Bayesian statistical framework, we could uncover subtle trends that would otherwise remain hidden.”
The full set of eROSITA all-sky scans will soon allow astronomers to probe even fainter and more distant quasars. Future analyses using these data – together with next-generation X-ray and multiwavelength surveys – will help reveal whether the observed evolution reflects a genuine physical change or simply selection effects.
Such studies will bring new insight into how supermassive black holes power the most luminous objects in the universe, and how their behaviour has evolved over cosmic time.
ENDS
eROSITA real image of a region of the X-ray sky centered at one of the quasars used in the new research.
Credit
Angel Ruiz (NOA) based on maps created by Jeremy Sanders (MPE)
An artist’s impression of matter spiralling inwards, pulled by the strong gravity of a central supermassive black hole, forming an “accretion disk”. Friction heats the infalling material to high temperatures producing intense ultraviolet light. This is reprocessed by hot plasma (extremely high temperature matter) believed to exist very close to the black hole — the “corona” — to produce energetic X-ray light.
Credit
Dimitrios Sakkas (tomakti), Antonis Georgakakis, Angel Ruiz, Maria Chira (NOA)
Images & captions
Caption: An artist’s impression of a bright quasar almost outshining its host galaxy.
Credit: Dimitrios Sakkas (tomakti), Antonis Georgakakis, Angel Ruiz, Maria Chira (NOA)
Caption: eROSITA real image of a region of the X-ray sky centered at one of the quasars used in the new research.
Credit: Angel Ruiz (NOA) based on maps created by Jeremy Sanders (MPE)
Central region of a supermassive black hole
Caption: An artist’s impression of matter spiralling inwards, pulled by the strong gravity of a central supermassive black hole, forming an “accretion disk”. Friction heats the infalling material to high temperatures producing intense ultraviolet light. This is reprocessed by hot plasma (extremely high temperature matter) believed to exist very close to the black hole — the “corona” — to produce energetic X-ray light.
Credit: Dimitrios Sakkas (tomakti), Antonis Georgakakis, Angel Ruiz, Maria Chira (NOA)
Further information
The paper ‘Revisiting the X-ray–to–UV relation of Quasars in the era of all-sky surveys’ by Maria Chira et al. has been published in Monthly Notices of the Royal Astronomical Society. DOI: 10.1093/mnras/staf1551.
Notes for editors
About the Royal Astronomical Society
The Royal Astronomical Society (RAS), founded in 1820, encourages and promotes the study of astronomy, solar-system science, geophysics and closely related branches of science.
The RAS organises scientific meetings, publishes international research and review journals, recognises outstanding achievements by the award of medals and prizes, maintains an extensive library, supports education through grants and outreach activities and represents UK astronomy nationally and internationally. Its more than 4,000 members (Fellows), a third based overseas, include scientific researchers in universities, observatories and laboratories as well as historians of astronomy and others.
The RAS accepts papers for its journals based on the principle of peer review, in which fellow experts on the editorial boards accept the paper as worth considering. The Society issues press releases based on a similar principle, but the organisations and scientists concerned have overall responsibility for their content.
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Journal
Monthly Notices of the Royal Astronomical Society
Article Title
Revisiting the X-ray–to–UV relation of Quasars in the era of all-sky surveys
Article Publication Date
11-Dec-2025
Ultra-hot lava world has thick atmosphere, upending expectations
JWST observations of the ultra-hot super-Earth exoplanet TOI-561 b show the strongest evidence yet for an atmosphere on a rocky planet beyond our Solar System
image:
Caption: This artist’s concept shows what the ultra-hot super-Earth exoplanet TOI-561 b could look like based on observations from NASA’s James Webb Space Telescope and other observatories. Webb data suggests that the planet is surrounded by a thick atmosphere above a global magma ocean.
view moreCredit: Credit: NASA, ESA, CSA, Ralf Crawford (STScI)
Washington, DC—A Carnegie-led team of astronomers detected the strongest evidence yet of an atmosphere around a rocky planet beyond our Solar System. Their work, published in The Astrophysical Journal Letters, used NASA’s JWST to reveal an alien atmosphere in an unexpected place—an ancient, ultra-hot super-Earth that likely hosts a magma ocean.
TOI-561 b is a rocky world that’s about twice Earth’s mass but bears little resemblance to our home planet due to its proximity to its host star. Although the star is slightly less massive and cooler than our Sun, the planet orbits at one fortieth the distance of Mercury in our own Solar System. On TOI-561 b, a year lasts just 10.56 hours, and one side of the planet is in perpetual daylight.
“Based on what we know about other systems, astronomers would have predicted that a planet like this is too small and hot to retain its own atmosphere for long after formation,” explained Carnegie Science Postdoctoral Fellow Nicole Wallack, the paper’s second author. “But our observations suggest it is surrounded by a relatively thick blanket of gas, upending conventional wisdom about ultra-short-period planets.”
In our own Solar System, smaller and hotter planets were not able to hang on to the primordial envelope of gas that surrounded them in their formative years. But TOI-561 b’s host star is much older than our Sun and its atmosphere remains intact.
The presence of this atmosphere could help explain the planet’s unusually low density.
“It’s not what we call a super-puff—or ‘cotton candy’ planet—but it is less dense than you would expect if it had an Earth-like composition,” explained Carnegie Science astronomer Johanna Teske, the paper’s lead author.
In designing the observing program, the team considered that the planet’s low density could be explained by a relatively small iron core and a mantle made of rock that is less dense than the rocks that comprise Earth’s interior.
Teske notes that this could make sense: “TOI-561 b is distinct among ultra-short period planets in that it orbits a very old—twice as old as the Sun—iron-poor star in a region of the Milky Way known as the thick disk. It must have formed in a very different chemical environment from the planets in our own Solar System.”
This means that its composition could be representative of planets that formed when the universe was relatively young.
But an exotic interior composition can’t explain everything.
In deciding to study TOI-561 b, the research team also suspected that it might be surrounded by a thick atmosphere that makes it look larger and thus less dense.
To test the existence of TOI-561 b’s atmosphere, the astronomers used JWST’s Near-Infrared Spectrograph (NIRSpec) instrument to measure the planet’s dayside temperature based on its brightness in the near-infrared. The technique, which involves measuring the decrease in brightness of the star-planet system as the planet moves behind the star, is similar to that used to search for atmospheres in the TRAPPIST-1 system and on other rocky worlds.
If TOI-561 b were a bare rock with no atmosphere to carry heat around to the nightside, its dayside temperature should be approaching 4,900 degrees Fahrenheit (2,700 degrees Celsius). But the NIRSpec observations show that the planet’s dayside appears to be closer to 3,200 degrees Fahrenheit (1,800 degrees Celsius)—still extremely hot, but far cooler than expected.
To explain the results, the team considered a few different scenarios. The magma ocean could circulate some heat, but without an atmosphere, the nightside would probably be solid, limiting flow away from the dayside. A thin layer of rock vapor on the surface of the magma ocean is also possible, but on its own would likely have a much smaller cooling effect than observed.
“We really need a thick volatile-rich atmosphere to explain all the observations,” said co-author Anjali Piette, of University of Birmingham, United Kingdom—a former Carnegie Science Postdoctoral Fellow. “Strong winds would cool the dayside by transporting heat over to the nightside. Gases like water vapor would absorb some wavelengths of near-infrared light emitted by the surface before they make it all the way up through the atmosphere. (The planet would look colder because the telescope detects less light.) It’s also possible that there are bright silicate clouds that cool the atmosphere by reflecting starlight.”
While JWST’s observations provide compelling evidence for such an atmosphere, the question remains: How can a small planet exposed to such intense radiation hold on to any atmosphere at all, let alone one so substantial? Some gases must be escaping to space, but perhaps not as efficiently as expected.
“We think there is an equilibrium between the magma ocean and the atmosphere. At the same time that gases are coming out of the planet to feed the atmosphere, the magma ocean is sucking them back into the interior,” said co-author Tim Lichtenberg from the University of Groningen in the Netherlands, who is also a member of the Carnegie-led Atmospheric Empirical Theoretical and Experimental Research (AEThER) project team. “This planet must be much, much more volatile-rich than Earth to explain the observations. It's really like a wet lava ball.”
Concluded Teske: “What’s really exciting is that this new data set is opening up even more questions than it’s answering.”
These are the first results from JWST’s General Observers Program 3860, which involved observing the system continuously for more than 37 hours while TOI-561 b completed nearly four full orbits of the star. The team is currently analyzing the full data set to map the temperature all the way around the planet and narrow down the composition of the atmosphere.
Teske and Wallack’s leadership on this JWST paper represents a tradition of Carnegie Science excellence dating back to the mission’s earliest conception three decades ago and extending through the first four cycles of time allocation on the revolutionary space telescope.
Since JWST finished calibrations and began collecting data for astronomical research programs, Teske, Wallack, and other Carnegie Earth and Planets Laboratory and Observatories-affiliated scientists have led more than a dozen JWST teams and announced groundbreaking results about exoplanet atmospheres, galaxy formation, and more.
“These JWST powered breakthroughs tap directly into our long-standing strength in understanding how exoplanet characteristics are shaped by planetary evolution and dynamics,” said Earth and Planets Laboratory Director Michael Walter. “There are more exciting results on the horizon and we’re poised for a new wave of Carnegie-led JWST science in the year ahead.”
This artist’s concept shows what a thick atmosphere above a vast magma ocean on exoplanet TOI-561 b could look like. Measurements of light captured from the planet’s dayside by NASA's James Webb Space Telescope suggest that in spite of the intense radiation it receives from its star, TOI-561 b is not a bare rock.
Credit
Credit: NASA, ESA, CSA, Ralf Crawford (STScI)
An emission spectrum captured by NIRSpec (the Near-Infrared Spectrograph) on NASA’s James Webb Space Telescope in May 2024 shows the brightness of different wavelengths of 3- to 5-micron light coming from the ultra-hot super-Earth exoplanet TOI-561 b. Comparisons of the data to theoretical models suggest that the planet is not a bare rock, but is instead surrounded by a volatile-rich atmosphere.
The data (white circles) are based on measurements of the change in brightness of the star-planet system before, during, and after the secondary eclipse, when the planet moves behind the star. Although TOI-561 b is too close to the star to see on its own, the amount of light coming from the planet can be calculated by subtracting the brightness of the star (measured when the planet is behind the star) from the brightness of the planet and star combined (measured when the planet is beside the star). TOI-561 b is thought to be tidally locked, which means that most of the planetary light measured during this observation is coming from the dayside.
Three model spectra are shown for comparison. If TOI-561 b has a dark bare-rock surface with no atmosphere (smooth gray line), or a thin rock-vapor atmosphere (jagged purple line), the dayside of the planet should appear significantly brighter than it actually does. Instead, the data are much more consistent with an atmosphere rich in volatiles like water, oxygen, and carbon dioxide. (The model shown here assumes an atmosphere that is 100% water vapor.)
Credit
Credit: Image - NASA, ESA, CSA, Ralf Crawford (STScI) Data - Johanna Teske (Carnegie Science Earth and Planets Laboratory), Anjali Piette (University of Birmingham), Tim Lichtenberg (Groningen), Nicole Wallack (Carnegie Science Earth and Planets Laboratory)
Journal
The Astrophysical Journal Letters
Method of Research
Observational study
Subject of Research
Not applicable
Article Title
A Thick Volatile Atmosphere on the Ultrahot Super-Earth TOI-561 b
Article Publication Date
11-Dec-2025
Scientists detect atmosphere on molten rocky exoplanet - study
University of Birmingham
image:
Super-Earth Exoplanet TOI-561 b and its Star (Artist's Concept)
view moreCredit: NASA/STScI
Researchers using NASA’s James Webb Space Telescope have detected the strongest evidence yet for an atmosphere on a rocky planet outside our solar system.
Observations of the ultra-hot super-Earth TOI-561 b suggest the exoplanet is surrounded by a thick blanket of gases above a global magma ocean.
Publishing their findings today (11 Dec) in The Astrophysical Journal Letters, researchers say that the results help to explain the planet’s unusually low density and challenge the prevailing wisdom that relatively small planets so close to their stars cannot sustain atmospheres.
With a radius 1.4 times Earth’s, and an orbital period less than 11 hours, TOI-561 b falls into a rare class of objects known as ultra-short period exoplanets.
Although its host star is only slightly smaller and cooler than the Sun, TOI-561 b orbits so close to the star — less than one million miles or one-fortieth the distance between Mercury and the Sun — that it must be tidally locked, with the temperature of its permanent dayside far exceeding the melting temperature of typical rock.
Co-author Dr Anjali Piette, from the University of Birmingham, said: “We really need a thick volatile-rich atmosphere to explain all the observations. Strong winds would cool the dayside by transporting heat over to the nightside.
“Gases like water vapour would absorb some wavelengths of near-infrared light emitted by the surface before they make it all the way up through the atmosphere. The planet would look colder because the telescope detects less light, but it's also possible that there are bright silicate clouds that cool the atmosphere by reflecting starlight.”
One explanation the team considered for the planet’s low density was that it could have a relatively small iron core and a mantle made of rock that is not as dense as rock within Earth.
Lead author Johanna Teske, staff scientist at Carnegie Science Earth and Planets Laboratory, said: “What really sets this planet apart is its anomalously low density. It is less dense than you would expect if it had an Earth-like composition.
“TOI-561 b is distinct among ultra-short period planets in that it orbits a very old, iron-poor star – twice as old as our sun - in a region of the Milky Way known as the thick disk. It must have formed in a very different chemical environment from planets in our own solar system.”
The planet's composition could be representative of planets that formed when the universe was relatively young.
The team also suspected that TOI-561 b might be surrounded by a thick atmosphere that makes it look larger than it is. Although small planets that have spent billions of years baking in blazing stellar radiation are not expected to have atmospheres, some show signs that they are not just bare rock or lava.
Using Webb’s NIRSpec (Near-Infrared Spectrograph) to measure the planet’s dayside temperature based on its near-infrared brightness, researchers tested the hypothesis that TOI-561 b has an atmosphere. The technique involves measuring the decrease in brightness of the star-planet system as the planet moves behind the star. It is like that used to search for atmospheres in the TRAPPIST-1 system and on other rocky worlds.
If TOI-561 b is a bare rock with no atmosphere to carry heat around to the nightside, its dayside temperature should be approaching 4,900 degrees Fahrenheit (2,700 degrees Celsius). But the NIRSpec observations show that the planet’s dayside appears to be closer to 3,200 degrees Fahrenheit (1,800 degrees Celsius) — still extremely hot, but far cooler than expected.
To explain the results, the team considered a few different scenarios. The magma ocean could circulate some heat, but without an atmosphere, the nightside would be solid, limiting flow away from the dayside. A thin layer of rock vapour on the surface of the magma ocean is also possible, but on its own would have a much smaller cooling effect than observed.
While the Webb observations provide compelling evidence for such an atmosphere, the question remains: How can a small planet exposed to such intense radiation hold on to any atmosphere at all, let alone one so substantial?
Co-author Tim Lichtenberg from the University of Groningen, Netherlands, said: “We think there is an equilibrium between the magma ocean and the atmosphere. While gases are coming out of the planet to feed the atmosphere, the magma ocean is sucking them back into the interior. This planet must be much, much more volatile-rich than Earth to explain the observations. It's really like a wet lava ball.”
These are the first results from Webb’s General Observers Program 3860, which involved observing the system continuously for more than 37 hours while TOI-561 b completed nearly four full orbits of the star. The team is analysing the full data set to map the temperature all the way around the planet and narrow down the composition of the atmosphere.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
ENDS
Image Caption – please credit NASA and STScI
- Super-Earth Exoplanet TOI-561 b and its Star (Artist's Concept)
- Super-Earth Exoplanet TOI-561 b (Artist's Concept)
Notes to Editors
- The University of Birmingham is ranked amongst the world’s top 100 institutions, its work brings people from across the world to Birmingham, including researchers and teachers and more than 8,000 international students from over 150 countries.
- ‘A Thick Volatile Atmosphere on the Ultra-Hot Super-Earth TOI-561 b’ - Johanna Teske et al is published in The Astrophysical Journal Letters.
Journal
The Astrophysical Journal Letters
Method of Research
Observational study
Subject of Research
Not applicable
Article Title
A Thick Volatile Atmosphere on the Ultra-Hot Super-Earth TOI-561 b
Article Publication Date
11-Dec-2025
Mars’ salty secrets: how ancient brines imprinted their chemical fingerprints in Martian minerals
Higher Education Press
image:
Selective incorporation of bromine and chlorine into K- and Na-jarosite across varying initial halogen concentrations under room temperature and hydrothermal conditions.
view moreCredit: HIGHER EDUCATON PRESS
New experiments reveal jarosite’s selective bromine capture under Mars-like conditions, offering a fresh lens to decode the Red Planet’s aqueous past and halogen cycling.
Jarosite, a sulfate mineral widely detected across the Martian surface, has long been regarded as a key indicator of past aqueous activity. Its occurrence reflects oxidizing, acidic waters that once interacted with Martian rocks, yet the detailed chemistry of those ancient fluids, particularly their halogen inventory, has remained difficult to reconstruct. Halogens such as bromine and chlorine are sensitive tracers of fluid evolution and environmental conditions, but the mechanisms by which they become incorporated into jarosite under Mars-relevant conditions have been poorly constrained.
In a new experimental study published in Planet (2025, 1(1)), researchers from the Institute of Geology and Geophysics, Chinese Academy of Sciences, and Chengdu University of Technology systematically investigated halogen partitioning behavior and structural incorporation mechanisms in potassium- and sodium-endmember jarosites. Their work, “Halogen partitioning and structural incorporation in K- and Na-jarosite: Experimental insights under Mars-relevant conditions,” provides the first comprehensive experimental evidence showing how bromine is preferentially captured by jarosite, particularly under cold, near-surface conditions analogous to those on ancient Mars.
To simulate plausible Martian aqueous environments, the team synthesized jarosite through two pathways: low-temperature Fe²⁺ oxidation at 25°C, and hydrothermal Fe³⁺ hydrolysis at 140°C. Integrated chemical, crystallographic, and spectroscopic analyses, including X-ray diffraction, Raman spectroscopy, and X-ray fluorescence, were used to quantify halogen uptake and identify substitution sites within the jarosite structure.
The results reveal a clear and robust trend: bromine is strongly favored over chlorine for incorporation into jarosite, with solid–liquid partition ratios for Br⁻ reaching values as high as 18 in potassium jarosite formed at 25°C. By contrast, sodium jarosite incorporated only trace halogens under all conditions, remaining persistently bromine- and chlorine-poor. This pronounced selectivity is governed not only by the halogen species but also by the identity of the alkali cation at the jarosite A-site, with K⁺-bearing jarosite exhibiting a substantially higher capacity for halogen substitution than its Na⁺ analog.
Mechanistically, combined evidence, from lattice parameter contraction, attenuation of Raman O–H stretching bands, and stoichiometric constraints, indicates that bromine and chlorine primarily substitute for structural hydroxyl groups rather than occupying interlayer positions. This substitution produces measurable lattice contraction, most strongly expressed in low-temperature K-jarosite enriched in bromine. The study further demonstrates that formation temperature exerts a major control on halogen incorporation: low temperatures promote bromine uptake through slower crystallization and defect-mediated trapping, whereas higher-temperature hydrothermal conditions yield more crystalline but halogen-poor jarosite. These findings complement prior observations of bromine enrichment in Martian-relevant evaporitic double salts, reinforcing the view that jarosite can act as a selective bromine sink in cold, acidic brines similar to those inferred for early Mars.
The implications of this work extend broadly across planetary science and future Mars exploration. By establishing a mechanistic link between jarosite composition, formation temperature, and halogen capture, the study provides a new geochemical framework for interpreting sulfate mineral assemblages on Mars. Notably, bromine-enriched jarosite, particularly potassium-dominated varieties, may indicate formation in low-temperature, chemically evolved brines, conditions conducive to more persistent aqueous activity on ancient Mars. The results also highlight jarosite’s dual role on planetary surfaces: not only as a paleoenvironmental archive, but also as an active participant in halogen cycling.
These insights will be especially valuable for upcoming Mars Sample Return missions, where high-resolution analyses of sulfate minerals could reveal the chemistry, timing, and evolution of Martian waters with unprecedented clarity.
Published in peer-review journal Planet, this work advances our understanding of water-rock interactions under Mars-like conditions and underscores the diagnostic potential of halogen signatures in sulfate minerals. By bridging laboratory synthesis with planetary observations, the study strengthens global efforts to reconstruct the history of water, habitability, and chemical evolution on the Red Planet.
Journal
Planet
Method of Research
Experimental study
Subject of Research
Not applicable
Article Title
Halogen partitioning and structural incorporation in K- and Na-jarosite: Experimental insights under Mars-relevant conditions
Rare image of Tatooine-like planet is
closest to its twin stars yet
Discovered in old data, new exoplanet was formed after the dinosaurs went extinct
Northwestern University
video:
Time-lapse footage of a newly discovered exoplanet as it makes its slow journey around two stars. To obtain the image of the planet, astronomers needed to remove the stars' glare. Two star icons mark the locations of where the stars would be in relation to their planet.
view moreCredit: Jason Wang/Northwestern University
In a discovery that’s fit for a movie, Northwestern University astronomers have directly imaged a Tatooine-like exoplanet, orbiting two suns.
While obtaining an image of a planet beyond our solar system is already rare, finding one that circles two suns is even rarer. But this new world is extra exceptional. It hugs its twin stars more tightly than any other directly imaged planet in a binary system. In fact, it is six times closer to its suns than other previously discovered exoplanets.
The discovery provides an unprecedented look at how planets move and form around multiple stars. It also offers a rare glimpse into how stars and planets orbit together, enabling astrophysicists to test theories of planet formation in complex systems.
The study will be published on Thursday (Dec. 11) in The Astrophysical Journal Letters. Also published in the journal Astronomy and Astrophysics, European astronomers at the University of Exeter report the same discovery.
“Of the 6,000 exoplanets that we know of, only a very small fraction of them orbit binaries,” said Northwestern’s Jason Wang, a senior author of the study. “Of those, we only have a direct image of a handful of them, meaning we can have an image of the binary and the planet itself. Imaging both the planet and the binary is interesting because it’s the only type of planetary system where we can trace both the orbit of the binary star and the planet in the sky at the same time. We’re excited to keep watching it in the future as they move, so we can see how the three bodies move across the sky.”
An expert in exoplanet imaging, Wang is an assistant professor of physics and astronomy at Northwestern’s Weinberg College of Arts and Sciences. He also is a member of the Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA). Nathalie Jones, the CIERA Board of Visitors Graduate Fellow at Weinberg and member of Wang’s research group, is the study’s lead author.
A discovery years in the making
The Northwestern team found the new exoplanet hidden within years-old data. When Wang was a Ph.D. student, he helped commission the Gemini Planet Imager (GPI), a specialized instrument designed to capture images of distant worlds by blocking out the overwhelming glare of their stars. Originally operated at the Gemini South telescope in Chile, GPI used adaptive optics and a coronagraph to sharpen images of faint planets orbiting bright stars.
“We undertook this big survey, and I traveled to Chile several times,” Wang said. “I spent most of my time during my Ph.D. just looking for planets. During the instrument’s lifetime, we observed more than 500 stars and found only one new planet. It would have been nice to have seen more, but it did tell us something about just how rare exoplanets are.”
Nearly a decade later, Wang asked Jones to revisit the data. Scientists and engineers currently are upgrading GPI. Next year, it will move to Hawaii, where it will be installed on the Gemini North telescope atop Mauna Kea. As GPI completed its first chapter in Chile, Wang decided it was time to wrap up his original search.
“I didn’t think we’d find any new planets,” Wang said. “But I thought we should do our due diligence and check carefully anyway.”
Tracking a suspicious object
Jones analyzed GPI data taken between 2016 and 2019 and cross-referenced it with data from the W.M. Keck Observatory, using Northwestern’s institutional access. Then, this past summer, she noticed something suspicious. A faint object appeared to be consistently following the motion of a star as it moved across the sky.
“Stars don’t stand still in a galaxy, they move around,” Wang said. “We look for objects and then revisit them later to see if they have moved elsewhere. If a planet is bound to a star, then it will move with the star. Sometimes, when we revisit a ‘planet,’ we find it’s not moving with its star. Then, we know it was just a photobombing star passing through. If they are both moving together, then that’s a sign that it’s an orbiting planet.”
“We also look at the light coming off an object,” Jones added. “We know what light from a star looks like versus what light from a planet looks like. We compared them and decided it better matched what we expect to see from a planet.”
To the team’s surprise, Jones verified the suspicious object was a planet, which GPI captured in 2016, but it had gone unnoticed in earlier analysis. Also this summer, a European team led by University of Exeter astronomers independently found the same planet in its own reanalysis of the data, confirming Jones’ discovery.
Born after dinosaurs walked the Earth
The confirmed planet is huge — six times the size of Jupiter. While hotter than any planet in our solar system, it’s relatively cool compared to other directly imaged exoplanets. It’s located about 446 light-years away from Earth, which Wang describes as “not within our local solar neighborhood but like the next town over.”
Having formed just about 13 million years ago, the new exoplanet also is quite youthful.
“That sounds like a long time ago, but it’s 50 million years after dinosaurs went extinct,” Wang said. “That’s relatively young in universe speak, so it still retains some of the heat from when it formed.”
The team also was struck by how close the exoplanet orbited around its host stars. The stars themselves tightly revolve around one another — taking just 18 Earth days to complete one revolution. The planet, however, takes 300 years to orbit the pair. That’s a little longer than Pluto takes to orbit our sun.
“You have this really tight binary, where stars are dancing around each other really fast,” Wang said. “Then there is this really slow planet, orbiting around them from far away.”
What’s next
Relatively speaking, though, the planet is much closer to its stars than other directly imaged exoplanets bound to binary systems. Although the Northwestern team does not know how this system formed, they posit the binary stars formed first. Then the planet formed around them.
“Exactly how it works is still uncertain,” Wang said. “Because we have only detected a few dozen planets like this, we don’t have enough data yet to put the picture together.”
The team plans to continue studying the system, so they can learn more about how it formed and how it works. Jones currently is writing proposals to obtain more data.
“I’m asking for more telescope time, so we can continue looking at this planet,” Jones said. “We want to track the planet and monitor its orbit, as well as the orbit of the binary stars, so we can learn more about the interactions between binary stars and planets.”
Showing that surprises can hide in plain sight, the discovery underscores the continuing scientific value of archival telescope data. Jones also continues to reanalyze the years-old data to see if previous astronomers missed anything else.
“There are a couple suspicious objects,” she said, “but what they are, exactly, remains to be seen.”
The study, “HD 143811 AB b: A directly imaged planet orbiting a spectroscopic binary in Sco-Cen,” was supported by the Alfred P. Sloan Foundation, U.S. Department of Energy, the National Science Foundation and the Gordon and Betty Moore Foundation. The Gemini North and Gemini South telescopes make up the International Gemini Observatory, which is funded in part by the U.S. National Science Foundation (NSF) and operated by NSF NOIRLab.
Journal
The Astrophysical Journal Letters
Method of Research
Observational study
Article Title
HD 143811 AB b: A directly imaged planet orbiting a spectroscopic binary in Sco-Cen
Article Publication Date
11-Dec-2025
Unlocking meteorite impact histories:
quantifies shock pressures in
enstatite chondrites
Higher Education Press
image:
Representative examples of 2D XRD images and microscopic images for selected enstatite grains in enstatite chondrites in the research.
view moreCredit: HIGHER EDUCATON PRESS
A new study published in Planet reveals a Micro-XRD method to quantitatively measure the ancient collision histories of meteorites. Researchers from China, Canada, and Japan have developed a quantitative technique to determine peak shock pressures in enstatite chondrites—rare meteorites chemically linked to Earth’s building blocks—using micro-X-ray diffraction (micro-XRD) method.
Why It Matters
Enstatite chondrites (ECs) formed under extreme reducing (oxygen-poor) conditions in the early Solar System. Their mineralogy provides critical clues about planet formation near the Sun and even offers analogs for Mercury’s surface. Though these meteorites preserve collision histories from ancient asteroid impacts, previous methods to gauge impact intensity relied solely on qualitative visual estimates (e.g., microscopic shock features).
The Innovation
Led by Dr. Matthew Izawa (from Okayama University), the team analyzed 11 ECs across all known shock stages (S1–S5). Using 2D micro-XRD, they measured strain-related mosaicity (SRM) in the mineral enstatite (MgSiO₃), a common planetary mineral. By correlating SRM—quantified as ΣFWHMχ (sum of X-ray peak widths along Debye rings)—with both established shock stages and shock pressure estimates from Rubin et al. (1997), they established a robust linear calibration:
Peak Pressure (GPa) = 4.62 × Î£FWHMχ + 0.57 (R² = 0.92, valid for 4–30 GPa).
Key Discoveries
- ΣFWHMχ data of enstatite (020), (610) and (131) lattice planes at each shock level shows that shock deformation is isotropic across all three enstatite crystal axes. Higher shock pressure produces bigger ΣFWHMχ value for these three lattice planes.
- The pressure model applies broadly to enstatite-rich planetary materials, enabling shock quantification in Martian meteorites and lunar samples.
Future Impact
This non-destructive micro-XRD technique unlocks transformative applications:
• High-throughput shock screening: Rapid pressure estimation for meteorite collections and future sample-return missions (e.g., Mars, asteroids).
• Asteroid collision forensics: Reconstructing impact histories of parent bodies to decode early Solar System dynamics.
Dr. Fengke Cao, co-author at Chengdu University of Technology, notes: "This work transforms shock quantification from art to science. We can now extract precise impact pressures from enstatite grains in any rock, from Earth’s craters to asteroid fragments."The study was funded by Natural Sciences and Engineering Research Council ofCanada (NSERC) Discovery Grants and Open Project for Innovative Platform of Meteoritical Research, Shanghai Science and Technology Museum.
Journal
Planet
Method of Research
Experimental study
Subject of Research
Not applicable
Article Title
Quantification of shock in enstatite chondrites using micro-X-ray diffraction
Satellites And Space Trash Threaten The Ozone Layer And Space Safety
Outer space has a trash problem.
“And the problem is only going to get bigger and bigger,” says Rannveig Færgestad.
Færgestad studies aerospace technology at the Norwegian University of Science and Technology (NTNU’s) Department of Structural Engineering. In her PhD, she has developed computer models that show what happens when pieces of space debris collide with spacecraft. With an average speed of 7 kilometres per second, even a tiny piece of junk can cause a lot of damage.
Rocket debris and satellites
Space trash consists of rocket remnants, fuel and whole or parts of defunct satellites. Much of this debris moves through the low Earth orbits below 2000 kilometres in altitude, or is on its way down into the atmosphere. This debris burns up in the layer of air surrounding the planet because air resistance creates intense friction.
All spacecraft that carries humans are covered with various types of protective shielding. Færgestad is conducting research on these kinds of shields in order to make them as safe as possible.
Greatest threat
One of her supervisors is former astronaut Kevin Anthony Ford from NASA (the National Aeronautics and Space Administration). He has completed three space missions and has served as commander of the International Space Station (ISS). He is now part of a team of advisors who continuously assess the safety situation for the ISS.
“The team now says that space trash is the greatest risk,” said Færgestad.
The most catastrophic scenario is if something hits a part of the space station containing people. If it forms a hole, the station loses pressure and the astronauts would die instantly.
A tenfold increase
More than 20,000 objects have been launched into space since the Russian Sputnik 1 satellite kicked things off on 4 October, 1957. That amounts to 50 thousand tonnes. Some of the debris has returned to Earth, but according to the European Space Agency (ESA), 10,000 tonnes are still floating around in orbit.
According to the United Nations Office for Outer Space Affairs, almost 2900 satellites, space probes and other objects were launched in 2024. That is more than ten times as many as a decade ago.
Orbiting space debris
If we continue to launch the same amount of equipment into space, the risk of collisions will only increase. The risk could become so great that developing shields strong enough to withstand such powerful impacts would be both challenging and expensive. Researchers warn of collisions that could trigger massive problems, wreaking havoc in many systems, such as communication and navigation, TV signals, banking services, and climate and weather forecasts.
In the worst case, collisions could destroy entire orbits.
Self-destructive satellites
“In the worst case scenario, it could simply become difficult to use these orbits for anything practical,” explained Færgestad.
“The ESA’s collision models show that even if all launches were to stop abruptly this year, the number of collisions would continue to increase over the next 200 years. Many companies already have large teams of engineers working to keep satellites safe and steer them away from collisions,” Færgestad said.
Moving the ISS
There are always people on the ISS and China’s Tiangong Space Station. If there is a risk of the stations being hit, they can be moved slightly to avoid a collision. In fact, the ISS astronauts perform these types of manoeuvres at least once a year.
“The most catastrophic scenario is if something hits a part of the space station containing people. If a hole forms, the station will lose pressure and the astronauts would die instantly,” Færgestad said.
Centimetre-sized pieces are particularly dangerous. So far, they have not hit the parts of the space station that house the astronauts, but they have created a clearly visible hole in a robotic arm on the ISS.
Elephant in the room
It could be said that Elon Musk is the elephant in the room with regard to outer space issues. He is the world’s richest man and controls the Starlink satellite network. The goal of Starlink is to provide internet access to the entire planet. Ukraine, for example, is entirely dependent on Starlink for its military communications and drone operations in the war against Russia.
Starlink alone has launched almost 8000 satellites since 2018, and they have been given the green light to launch a total of 40,000. Other satellite mega-constellations, i.e. large private networks, have similar plans. On 28 April 2024, Amazon launched the first 27 of over 3000 planned Kuiper satellites. Communication networks like OneWeb, Telesat and China’s StarNet are all waiting in line.
This means that the number of satellites is skyrocketing.
Satellites can harm the ozone layer
In a 2021 article published in the science journal Nature, researchers from the University of British Columbia in Canada warned that rocket launches and mega-constellations could harm the ozone layer that protects us from UV radiation. A number of research groups have since followed up on this finding.
A typical satellite weighs around 250 kilograms. Sooner or later, they stop working, just like your TV or washing machine. They then return to the atmosphere, burn up, and release around 30 kilograms of aluminium dust, which can harm the ozone layer.
Experts warn that this kind of dumping could cause a large-scale, uncontrolled change in the natural chemistry of the atmosphere.
Many satellites die every day
Many of the first Starlink satellites have already reached the end of their useful life. In January 2025 alone, 120 of them had lost enough altitude to fall into the atmosphere and burn up. This is completely according to plan, and satellite trackers at the Harvard Center for Astrophysics state that 4 to 5 derelict Starlink satellites burn up every single day.
Scenarios developed by American researchers suggest that these satellite mega-constellations could collectively add 360 tonnes of aluminium oxide compounds to the atmosphere each year when their satellites are decommissioned and die. The particles fall slowly, so it could take 30 years before they reach the ozone layer – and we see the effects.
“That is really quite worrying,” said Færgestad.
Must clean up
Beyond enabling communication and navigation services, satellites are widely used to monitor the environment and climate. They monitor sea levels, algal blooms, melting glaciers, landslides, floods, overfishing and climate change.
Agencies are working to tackle the problem posed by the aluminium dust from dying satellites, including through the ESA’s Zero Debris approach. Any company that is launching objects into space must now have a plan in place for what they are going to do with them when the equipment stops functioning.
Graveyards in the ocean and outer space
For satellites in Low Earth Orbit, engineers can use the last remaining energy in the satellites to slow them down. As a result, they lose altitude and burn up when they reach the Earth’s atmosphere.
Satellites in the highest orbits can be moved to designated graveyard orbits. These are located so far away that there is no risk of collision.
For larger objects, such as capsules or spacecraft, the aerospace industry has chosen the most remote place on planet Earth: ‘Point Nemo’, or the ‘Oceanic Pole of Inaccessibility’, in the Pacific Ocean, which is more than 2600 kilometres from the nearest land. There, at a depth of 3000 metres, lies the world’s largest spacecraft graveyard.
Every gram costs
In autumn 2025, Færgestad will defend her PhD at NTNU. She says that awareness of safety in unmanned spaceflight is increasing. Satellites and space probes will now also be protected by shields.
Every gram of equipment launched into outer space costs money, which is why everything is focused on reducing weight. Færgestad’s research is helping make the shields as light – and as safe – as possible. On the ISS alone, there are hundreds of types and combinations of shields. Different parts are made from different materials and will react differently if they are hit. Therefore, they also require different protection.
Layer upon layer upon layer
The protective shields are 10-15 centimetres thick and consist of multiple panels made of materials such as Kevlar, carbon fibre, fibreglass and foam. The exterior is usually aluminium, with an air cavity between each panel. If a piece of space debris comes hurtling through space and hits the shield, the air cavity between the panels absorbs some of the impact.
“Exactly what happens when something strikes the shield depends on its speed, temperature and the material it is made from,” she said.
If the debris is moving slower than 3 kilometres per second, it will break up into smaller pieces. At speeds of 7 kilometres per second or more, everything is vaporized into a cloud of molten droplets. The air cavities dampen the impact of the fragments in the cloud of debris, spreading the energy over a larger area in the subsequent layers.
The physics of these collisions is extremely complex and difficult to describe in computer models.
“We are talking shock physics,” said Færgestad.
This involves understanding how materials behave under the most extreme stresses that exist – such as explosions, meteorite impacts and hypervelocity collisions in space.
Tests in Italy and the United States
In order to create computer models that can simulate what happens as accurately as possible, the researchers also conduct physical tests. The tests are needed to check whether the computer models reproduce what happens in reality as accurately as possible.
Færgestad has tested panels at NASA’s hypervelocity laboratories in New Mexico and the University of Padua in Italy. These facilities have gas guns capable of firing projectiles at speeds of up to 7 and 5.5 kilometres per second, respectively. All the tests were filmed using high-speed cameras that capture up to one million frames per second.
She is very pleased with the results; the behaviour observed in the laboratory tests appears to align very closely with her computer simulations.
Larger toolbox
The 30-year-old has chosen a very specialized field of study in which she is one of very few researchers in Norway. Slow progress is being made, one step at a time.
“It is probably not the kind of work that makes you think, ‘Wow, this is going to get me a Nobel Prize’,” said Færgestad with a wry smile.
“But what we know and how we understand thing are getting better. The tools are getting better. The computers are getting more processing power. We are trying to make the toolbox for everyone working in aerospace bigger, better and as reliable as possible,” she said..
Making equipment safer also means it will also last longer before it stops working and turns into dangerous space debris.
Astronaut? Yes absolutely!
Ever since she was in upper secondary school in Drøbak and attended the European Space Camp at Andøya, Færgestad has been passionately interested in aerospace and space technology.
In autumn 2025, she will start working as a Space Debris Mitigation Engineer for the Italian company Thales Alenia, which is one of the major aerospace companies in Europe. They have built a lot of the components for the International Space Station. Currently, they are building modules for the planned space station that will orbit the Moon, and they are designing spacecraft for lunar landings and unmanned vehicles destined for Venus.
How long would you have to think about it if you were offered the chance to become an astronaut? – “There’s nothing to think about. If you get an opportunity like that, you seize it.”
Why SpaceX IPO plan is generating so much buzz
Washington (United States) (AFP) – More than 20 years after founding SpaceX, the record-breaking company that transformed the global space industry, Elon Musk is planning to take the enterprise public.
Issued on: 13/12/2025 - RFI
Here is a look at what is expected to be the largest IPO in history.
What's at stake?
SpaceX is owned by Elon Musk alongside several investment funds. Tech giant Alphabet, Google's parent company, is also among the space company's shareholders.
A public listing would open SpaceX to a broader and more diverse pool of investors, including individual buyers, while giving existing shareholders an easier path to cash out and realize substantial capital gains.
"This is a capital intensive business," Matthew Kennedy of Renaissance Capital investment management firm told AFP.
"SpaceX has never had any difficulty raising funds in the private market, but public markets are undoubtedly larger. Liquidity is important as well, it can help with making acquisitions."
According to Bloomberg and the financial data platform PitchBook, the IPO could raise more than $30 billion, an unprecedented sum for a deal of this kind and far more than the $10 billion the company has raised since its inception.
This would bring its total valuation to $1.5 trillion.
Why so much money?
The IPO comes amid a boom in the space industry.
Worth $630 billion in 2023, the sector is expected to triple in size by 2035, according to the consulting firm McKinsey and the World Economic Forum.
And SpaceX, which dominates the space launch market with its reusable rockets and owns the largest satellite constellation through Starlink, has a unique appeal.
It's "kind of a black swan event and unique so that we can't draw too many parallels across the whole space economy," Clayton Swope of the Center for Strategic and International Studies (CSIS) told AFP.
Its unique status is also tied to its CEO Musk, the world's richest person, who is also the CEO of Tesla and xAI.
Musk has already pushed Tesla's valuation far beyond that of Toyota and Volkswagen despite selling five to six times fewer vehicles.
Why now?
This is the question on everyone's mind, as the billionaire had long dismissed such a possibility. Since its founding in 2002, SpaceX has held a special place for the billionaire, given his ambition to colonize Mars.
This goal reflects the company's priorities, which include developing Starship, the largest rocket ever built for missions to the Moon and Mars, as well as plans to build space-based data centers for artificial intelligence (AI).
A stock market listing could provide new liquidity that would support all of these projects.
"The answer is pretty straightforward," said Swope. "He wants to accelerate the flywheel for his vision of humanity on Mars."
What next?
The influx of capital from an IPO will come at a price: going public will require SpaceX and Elon Musk to maintain greater transparency, particularly about its revenues, and could increase pressure to deliver profits.
"I speculate that would ground SpaceX somewhat in the near term," said Mason Peck, an astronautical engineering professor at Cornell University.
The company's risk-taking approach of experimenting with unproven technologies and frequent prototype launches to learn from mistakes could be constrained by the expectations of new shareholders.
"Will they become the same as any other aerospace company and ultimately mired in conservatism and legacy solutions?" Peck said. "That's entirely possible. I hope it doesn't happen."
Swope, however, sees such a scenario as unlikely.
"I think they are willing to take that risk and willing to let Elon Musk and SpaceX have this vision, because that is integral to what makes SpaceX also a successful business," he said.
© 2025 AFP
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