SPACE/COSMOS
Venus: Dead? Far from it
image:
There are huge rift valleys on Venus. They suggest that the planet is still geologically active.
view moreCredit: (Image: NASA/JPL/USGS)
Venus is an inhospitable place, with temperatures soaring to several hundred degrees Celsius and no oceans like those on Earth. Planetary scientists long believed Venus was geologically dormant. However, recent research indicates that Venus remains geologically “alive” and even hosts active volcanoes.
Rift valleys, which indicate tectonic activity, can be vast and resemble those on Earth, such as the African Rift Valley. On Venus, they can span up to 10,000 kilometres.
The timing of these rifts’ formation is uncertain. Geoscientists believe they originated more than 100 million years ago and are therefore remnants of the past.
Simulations indicate tectonic activity
ETH researchers, led by Taras Gerya, Professor of Geodynamics at the Department of Earth and Planetary Sciences, have used a new computer model to demonstrate that some rift valleys may have formed relatively recently. The planetary scientists also addressed the long-standing question of whether Venus is geologically active. This study has been published in Nature Geoscience. Lead author Xi Yang conducted the research as part of his Master’s studies under Gerya’s supervision.
Yang and his team used a new computer model to simulate high-resolution, 3D rifts for the first time. This allowed them to accurately replicate these rift structures in simulations and provide better explanations of their formation. Earlier models had relied on simplified material assumptions and been mostly two-dimensional.
The models indicate that broad ridges, known as rift flanks, form along the edges of rift valleys when the rifts are geologically young and either still actively moving or have only recently stopped moving. The simulations also suggest that these rifts widen more rapidly than had been previously believed, at a rate of 3 to 10 centimetres per year.
Yang and his colleagues also show that the rift flanks tend to flatten rapidly after movement ceases; the older the rift system, the less steep and narrow its flanks. Unlike Earth, where erosion gradually wears down features, Venus’s flanks subside due to crustal relaxation.
Wide and high rift flanks are not only produced by the computer model but can also be seen in images of the Venusian surface from the Magellan probe during its 1990’s mission.
Based on their simulations and observational data, the researchers conclude that Venus remains an active planet with a more dynamic interior than had been previously believed. “The results help us to better assess the tectonic activity on Venus,” says Gerya.
Supporting future Venus missions
The results of the ETH researchers’ model could help pinpoint active regions worthy of detailed investigation for these missions. Additionally, the study enhances our understanding of how rocky planets form. Importantly, the researchers aim to uncover clues that could improve the detection of rocky exoplanets.
Growing interest in our neighbouring planet
Interest in Venus is increasing as NASA and ESA prepare multiple missions to explore Earth’s neighbouring planet.
ETH geophysics professors Paul Tackley and Taras Gerya, along with their collaborators, are participating in ESA’s EnVision mission. They are developing instruments for the Venus orbiter to analyse the planet’s surface. The mission, scheduled for launch in the early 2030s, will explore the planet more thoroughly, from its core to its upper atmosphere.
Journal
Nature Geoscience
Article Title
Recent active rifting on Venus revealed by wide rift flank uplifts
Could alien signals be hiding on a different radio channel?
image:
ALMA's DV-59 antenna in the foreground with multiple other antennas observing the sky in a night dominated by the Moon.
view moreCredit: ALMA / Alex Pérez / CC BY 4.0
Astronomers searching for signs of extraterrestrial intelligence may have been missing alien signals in part of the radio spectrum that has not recently been explored.
Most radio SETI (Search for Extraterrestrial Intelligence) surveys have focused on frequencies between 1.42 and 1.66 GHz. This range is known as the 'water hole' because it lies between the natural radio frequencies emitted by hydrogen and hydroxyl, two molecules whose combination forms water.
Scientists have long thought that this relatively quiet part of the radio spectrum would be a logical place to communicate, as a technologically advanced civilisation might recognise the significance of hydrogen and hydroxyl and be likely to transmit and listen there.
But a new study suggests that higher radio frequencies could provide an important new avenue in the search for possible technological signals from other civilisations. The research is being presented this week at the Royal Astronomical Society's National Astronomy Meeting in Birmingham.
Using archived observations from the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, astronomer Louisa Mason, a PhD researcher at the University of Manchester, carried out the first-ever SETI survey using the telescope. Rather than making new observations, she analysed existing data originally collected for other astronomical purposes.
She looked for narrowband radio signals that might indicate the presence of technology rather than natural astrophysical processes.
"For decades, SETI searches have concentrated on a relatively small part of the radio spectrum. We wanted to ask what might happen if we looked somewhere very different," Mason said.
"The millimetre and submillimetre radio bands remain almost completely unexplored for SETI, so this is really about opening up a new area of parameter space to search."
Mason searched two small frequency windows in ALMA's Band 3 observations but found no candidate technosignatures (alien signals) above their thresholds.
Although the survey examined only four archived ALMA observations, Mason says the work demonstrates that high-frequency radio telescopes could play an important role in future SETI programmes.
The research also highlights an overlooked opportunity hidden within every radio observation: when astronomers point a telescope at a single target, they also capture many other stars within the telescope's field of view.
Traditionally, researchers have estimated this 'stellar bycatch' using catalogues such as Gaia. Instead, Mason used the Besançon Galactic Model to estimate the full stellar population contained within each observation, including stars too distant, too faint or too difficult to identify reliably in existing catalogues.
Applying the technique to a previous SETI survey of 1,327 telescope pointings increased the estimated number of stars included in the search from around 288,000 identified using Gaia to more than 6.1 million using the galactic model.
Mason says this provides a much more realistic picture of how much of the galaxy has actually been surveyed for technosignatures.
"One of the most exciting things about this work is realising that we've surveyed many more stars than initially thought," she said.
"Even a very small observation can contain a huge number and diversity of stars that we might never have intended to study. By combining high-frequency observations with galactic simulations, we can better understand exactly what we've searched and where we should look next."
Mason emphasises that the absence of any detected signal does not mean intelligent life does not exist, only that no candidate signal was found within the small frequency ranges examined in this study. Instead, she hopes the work will encourage future SETI surveys to search more widely across the radio spectrum and make better use of existing astronomical observations.
The work was done in collaboration with Professor Michael Garrett, Dr Andrew Siemion and Dr Kelvin Wandia.
ENDS
Images & captions
Image 1: ALMA's DV-59 antenna in the foreground with multiple other antennas observing the sky in a night dominated by the Moon.
https://drive.google.com/file/d/1qBkjttr8PMnIotJ3m1QM4znBIi7XcGnI/view?usp=drive_link
Credit: ALMA / Alex Pérez / CC BY 4.0
Figure 1: Figure showing the frequency coverage and power of a signal that each facility could be sensitive to. This highlights the fact that no other instruments are conducting SETI at high frequencies, and ALMA has an exciting frequency coverage yet to be explored.
https://drive.google.com/file/d/1B3X3IycbX0bK6GRcQpfP7DPgWWyoUUCg/view?usp=drive_link
Credit: Louisa Mason
Figure 2: Figure of stellar bycatch demonstrating the breadth of stellar objects that could be captured within a single pointing. This example is for a generic direction (l=0 deg, b = 30 deg) for a 5 arc second field of view.
https://drive.google.com/file/d/1FNo5Tupm-PUL_XqBl0PiTxybm235GMA4/view?usp=drive_link
Credit: Louisa Mason
Figure 3: This figure shows the diversity in the stellar bycatch population considered through the use of galactic models (such as BGM). The red overlay is stars found through the Gaia catalogues, highlighting that galactic models simulate the full breadth of Main Sequence stars, as well as clearly distinguishing the white dwarf population.
https://drive.google.com/file/d/16zmO3fq2oeNwmDdz22RrjqUH1Ic-luOf/view?usp=drive_link
Credit: Louisa Mason
Further information
Relevant papers
Louisa A Mason, Michael A Garrett, Andrew P V Siemion, Simulating the stellar bycatch: constraining the prevalence of extraterrestrial transmitters within radio SETI surveys, Monthly Notices of the Royal Astronomical Society, Volume 545, Issue 3, January 2026, staf2112, https://doi.org/10.1093/mnras/staf2112
Louisa A Mason, Michael A Garrett, Kelvin Wandia, Andrew P V Siemion, Conducting high-frequency radio SETI searches using ALMA, Monthly Notices of the Royal Astronomical Society, Volume 536, Issue 3, January 2025, Pages 2127–2134, https://doi.org/10.1093/mnras/stae2714
The poster 'Strategies Utilising High-Frequency Interferometric Data to Explore SETI Parameter Space' is part of the Statistical Challenges for Next-Generation Astronomical Surveys session at NAM2026 from 14:15-15:45 BST on Friday 24 July 2026 in room PW117. Find out more at: https://uobevents-national-astronomy-meeting-2026.eventsairsite.com/block-schedule.
Notes for editors
About the Royal Astronomical Society
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Analysis of defense technology for large-sized near-Earth asteroids
Beijing Institute of Technology Press Co., Ltd
image:
Virtual potential threat asteroid database. (A) Virtual asteroid orbit that will impact Earth 1 year later.
view moreCredit: Space: Science & Technology
Near‑Earth asteroid impacts pose a major threat that could lead to the destruction of human civilization, having already caused catastrophic environmental changes and mass extinctions multiple times in history. In recent years, asteroids with diameters ranging from tens to hundreds of meters have frequently made close flybys of Earth, and a large number of large‑sized asteroids remain undiscovered, with warning times often only a few days to weeks. For large‑sized asteroids exceeding 100 meters in diameter, or even kilometer‑scale ones, traditional kinetic impact or long‑term force deflection methods offer limited energy and cannot achieve effective deflection within short timeframes. Using the enormous energy generated by nuclear detonation to directly destroy or rapidly deflect the asteroid's orbit is the most effective, and in extreme cases the only feasible, approach for dealing with large asteroids or those with short warning times. However, existing research on detonation defense has mostly focused on the direct rendezvous impact mode, in which the impact and detonation positions cannot be autonomously selected and energy coupling is relatively weak. Moreover, there is a lack of systematic analysis of the capability coverage and overall effectiveness of different defense modes, severely constraining the optimization of engineering designs.
In a recent study published in Space: Science & Technology, the team led by Researcher Wang Xiaowei from the China Academy of Launch Vehicle Technology proposed a novel approach to detonation defense technology for large‑sized near‑Earth asteroids. Building on the energy advantages of nuclear detonation, the study proposed two defense modes: a direct rendezvous impact detonation mode and a novel flyby pre‑excavation detonation mode. By establishing a virtual threat asteroid database and using the finite element method‑smoothed particle hydrodynamics adaptive method to simulate damage effects under various yields and burial depths, the study systematically analyzed the influence of key factors, including launch vehicle characteristic energy (C3), impact velocity, and velocity increment provided by the space transfer platform, on defense coverage and deflection effectiveness. The results demonstrate that the flyby pre-excavation detonation mode, due to its ability to autonomously select the cratering location and achieve deep detonation, offers stronger energy coupling. It can directly destroy hundred-meter-scale asteroids and achieve velocity increments of tens of centimeters per second or more for kilometer‑scale asteroids, several times higher than those of the direct rendezvous mode, while also entailing lower technical difficulty, making it the preferred option when warning time permits. When the velocity increment reaches 1 m/s, the deflection target can be achieved in only 60 days. This study provides an important theoretical foundation for mission planning and engineering design of defense against large-sized or short-warning-time near-Earth asteroids, and holds profound strategic significance for enhancing humanity's capability to respond to asteroid impact threats.
The study focuses on the severity of impact threats posed by large-sized near-Earth asteroids and the necessity of detonation defense technology, and proposes two detonation defense modes. Asteroids with diameters exceeding 100 meters can trigger large‑scale, intercontinental, or even global catastrophes, yet a large number of such asteroids remain undiscovered, with warning times often being extremely short (for example, 2024 MK had only 13 days). Nuclear detonation, due to its enormous energy, is the most effective means of dealing with large asteroids with short warning times. On this basis, the study proposes two defense modes: Mode 1 is the direct rendezvous impact detonation mode, in which a defender directly impacts the asteroid's surface at high speed to form a shallow crater, after which a nuclear device detonates within that shallow crater. Mode 2 is a novel flyby pre-excavation detonation mode, in which a space transfer platform first releases a conventional penetration device to pre-excavate a deep crater on the asteroid, and then guides a nuclear device into the deep crater for detonation. The core difference between the two modes is that Mode 1 has a simple system and can be launched immediately, but the impact location is random, energy coupling is weak, and requirements for the nuclear device's impact resistance and detonation timing are extremely stringent. Mode 2 has a more complex system and requires a longer warning time, but it can autonomously select the cratering location, achieve deep nuclear detonation, and provides strong energy coupling. To comprehensively evaluate defense capability, the study established a virtual threat asteroid database (as shown in Fig. 1), taking relative velocity (10 km/s) and angular ranges α (0°-360°) and β (40°-90°) as variables, and generated virtual asteroid orbit libraries for 1‑year and 20‑year warning times through backward integration of orbital dynamics, providing a baseline for subsequent effectiveness analysis.
The study also conducted quantitative analyses of the key influencing factors for both modes. For Mode 1, a two-pulse optimal transfer orbit model was established to analyze the effects of launch vehicle characteristic energy (C3) and maximum impact velocity on deflection time. As shown in Fig. 2, when C3 is 30 km²/s² and the maximum impact velocity is 10 km/s, only 30% of asteroids can achieve a deflection time exceeding 50 days. When the velocity is increased to 20 km/s, all asteroids have deflection times exceeding 30 days, with approximately 16% exceeding 150 days. Further increasing the velocity to 30 km/s yields only marginal gains, indicating that 20 km/s represents a more favorable design point for Mode 1, though this velocity poses significant challenges for the design of nuclear devices resistant to high-speed impact. For Mode 2, a three-pulse transfer orbit model was established to analyze the influence of the velocity increment provided by the space transfer platform on asteroid defense coverage. Fig. 3 shows that the velocity increment requirements for all virtual asteroids are below 10 km/s, with about 45% requiring less than 6 km/s. Therefore, space transfer platforms using chemical propulsion (specific impulse 300-460 seconds) or electric propulsion (specific impulse 4,000-10,000 seconds) can achieve coverage for most threat sources. In addition, the finite element method-smoothed particle hydrodynamics method was used to simulate damage effects under various explosive yields and burial depths. Fig. 4 illustrates the damage morphology of a kilometer-scale asteroid under a 3-megaton TNT equivalent detonation at a burial depth of 5 meters, showing that craters on the order of hundreds of meters can be formed and significant velocity increments can be generated.
Finally, the study compared the defense effectiveness of the two modes against large-sized asteroids and provided recommended solutions. For hundred-meter-scale asteroids, both modes can directly destroy them. For kilometer-scale asteroids, Mode 1, under a 3‑megaton TNT equivalent detonation at a shallow crater depth of 5 meters, produces a velocity increment of 8 to 9.2 cm/s. In contrast, Mode 2, with a deep crater detonation at 20 meters, achieves a velocity increment exceeding 30 cm/s, representing an order of magnitude improvement in effectiveness. Based on the virtual database, the study further analyzed the minimum warning time required for successful deflection under different velocity increments (as shown in Figs. 5 to 8). When the velocity increment is 0.5 cm/s, a minimum of 4.45 years is required; at 3 cm/s, 560 days are needed; at 18 cm/s, 139 days suffice; and at 1 m/s, only 60 days are required. This indicates that Mode 2, due to its ability to generate higher velocity increments, can substantially shorten the required warning time. In a comprehensive comparison, Mode 1 is suitable for emergency defense under extremely short warning times, though it entails high technical difficulty. Mode 2, when warning time permits, offers lower technical complexity and more reliable defense effectiveness, and can therefore serve as the preferred solution for large-sized near-Earth asteroid defense. This study provides a systematic theoretical foundation and data support for the engineering design and mission planning of future asteroid defense missions in China.
Distribution of minimum number of days prior to impact when the speed increment is 3 cm/s.
Distribution of minimum number of days prior to impact when the speed increment is 1 m/s.
Credit
Space: Science & Technology
Space: Science & Technology
Journal
Space: Science & Technology
Article Title
Analysis of Defense Technology for Large-Sized Near-Earth Asteroids
Why Europa’s hidden ocean may be more difficult to reach than scientists thought
A Rutgers scientist says shallow water on Jupiter’s icy moon may not offer a direct window into its deep subsurface
image:
Europa, one of Jupiter’s icy moons, has drawn scientific interest because its frozen surface may hide a global ocean with conditions that could support life.
view moreCredit: NASA/JPL-Caltech/SETI Institute
Europa, one of Jupiter’s icy moons, long has fascinated scientists because of what may lie beneath its frozen shell: a global ocean of liquid water.
That hidden ocean has made Europa one of the most compelling places in the solar system to study the conditions that might support life. But new research led by Rutgers scientist Lujendra Ojha suggests one of the most promising shortcuts to Europa’s ocean may be far more complicated than previously thought.
In a study published in Nature Astronomy, Ojha and colleagues used computer simulations to test whether liquid water from Europa’s deep ocean could rise through cracks in the ice and collect in shallow reservoirs closer to the surface. Such reservoirs, if they exist, could be easier for future missions to detect or sample than the ocean buried far below.
“The mystery we wanted to solve was whether this journey is actually possible,” said Ojha, an associate professor in the Department of Earth and Planetary Sciences at the Rutgers School of Arts and Sciences. “Can liquid water rise from Europa’s deep ocean toward the surface without freezing along the way?”
Their conclusion: The route from deep ocean to shallow ice is probably much more difficult than scientists have assumed.
“There’s an icy shell, there’s water underneath, and there’s all this speculation about how that water can come from deep underground and make its way all the way up without freezing en route,” Ojha said. “That’s really what we think we disproved.”
The finding has important implications for future exploration of Europa. If shallow pockets of liquid water are found beneath the moon’s surface, they may not necessarily contain water from Europa’s deep ocean. Instead, they may have formed locally, from ice that melted within the shell itself.
That distinction matters. Scientists are interested in Europa because liquid water, chemistry and energy are all essential ingredients in the search for habitable environments beyond Earth. A shallow reservoir would be easier to reach than the deep ocean. But if that reservoir isn’t connected to the ocean, it may not reveal what is happening in Europa’s most intriguing environment.
The work arrives as two major spacecraft missions are on their way to the Jupiter system. NASA’s Europa Clipper mission launched in October 2024 and is scheduled to arrive at Jupiter in April 2030, where it will orbit the planet and make 49 close flybys of Europa. The European Space Agency’s Jupiter Icy Moons Explorer mission, known as JUICE, launched in April 2023 and is scheduled to arrive at Jupiter in July 2031.
Together, the missions are expected to give scientists a far more detailed view of Europa’s ice shell, surface composition and possible subsurface water. Europa Clipper’s radar instrument may help scientists determine whether shallow reservoirs exist and how they are structured.
Beneath Europa’s extremely cold surface, a global ocean may remain liquid because Jupiter’s powerful gravity continually squeezes and stretches the moon, generating internal heat that is trapped by the overlying ice shell.
The study focuses on dikes, narrow cracks or fractures that could, in theory, allow water from the ocean to rise upward through the ice. The idea is somewhat similar to the way molten rock can move through cracks on Earth before feeding volcanic activity. On icy worlds, the process is known as cryovolcanism, or volcanism involving ice and water rather than molten rock.
Ojha said that comparison is useful only up to a point.
“Ice and liquid water are fundamentally different than lava and the volcanoes that we see here on Earth,” he said. “I think there’s some fundamental physics that’s missing here, and so I wanted to explore that.”
One missing piece, Ojha said, is turbulence. Earlier models often treated water rising through Europa’s ice as if it moved in a relatively orderly way. But the Rutgers-led simulations suggest the water would likely move fast and turbulently through the fractures, mixing against the cold walls of the crack and losing heat quickly into the surrounding ice.
“This water that’s going to come up, it’s going to be turbulent,” Ojha said. “It’s going to be left and right, it’s going to be up and down, it’s going to have a swirling motion. And when that happens, that liquid water is going to cool very, very fast as it approaches the surface.”
As the water cools, it can become supercooled, meaning it remains liquid even after dropping below its normal freezing temperature. Under those conditions, tiny ice crystals called frazil ice can form, build up and clog the pathway.
The simulations show that narrow cracks could freeze shut within hours. Wider cracks could carry more water under idealized conditions, but turbulence makes those scenarios far less favorable. The researchers found that to deliver enough water to form some of Europa’s surface features, the fractures would need to be unrealistically long or occur in large numbers.
The result is a picture of Europa in which shallow water, if present, may have a different origin than many scientists have hoped. Rather than rising directly from the ocean, the water may be produced by localized heating and melting inside the ice shell.
“Our work suggests that Europa’s ice shell may be a stronger barrier between the ocean and the surface than previously assumed,” Ojha said. “This helps future missions interpret what they find and better understand where to look for signs of habitability.”
Explore more of the ways Rutgers research is shaping the future.
Journal
Nature Astronomy
Method of Research
Computational simulation/modeling
Subject of Research
Not applicable
Article Title
Limited direct fluid exchange between the deep subsurface ocean and the shallow subsurface environment of Europa
Article Publication Date
23-Jul-2026
Rocks from unexplored far side of the moon help rewrite lunar history
Ancient samples from the Moon’s far side are helping scientists uncover how asteroid impacts shaped the early Solar System. The findings challenge decades of thinking about when those impacts occurred and offer new insights into the conditions that influenced Earth’s evolution.
Researchers studying lunar rocks have uncovered new evidence about the timing and intensity of asteroid bombardment across the Moon’s surface, finding it declined gradually, rather than being a short, intense burst of impacts as previously thought.
Unlike Earth, where ancient geological evidence has been largely erased by erosion, volcanic activity and shifting tectonic plates, the Moon has preserved a record of impacts stretching back billions of years.
Research co-author Dr Fred Jourdan, from Curtin University’s School of Earth and Planetary Sciences and John de Laeter Centre, said lunar rocks acted as a natural archive of the Solar System’s history, allowing scientists to investigate events that occurred shortly after the planets formed.
“The Moon is like a time capsule — it has preserved a record of events that have been erased from Earth by erosion, plate tectonics and other geological processes,” Dr Jourdan said.
“Samples collected from the Moon’s far side are particularly significant because they allow us to compare two very different parts of the Moon for the first time. Until now, almost everything we knew came from the side facing Earth.”
“By analysing these ancient rocks, we can better understand when major asteroid impacts occurred and how the early Solar System evolved. The far side preserves a cleaner record of those earliest impacts because it was much less affected by later geological events than the side facing Earth.
“These samples are helping us rewrite parts of the Moon’s history and suggest the early Solar System experienced a long decline in asteroid impacts rather than a single catastrophic bombardment.”
The research team analysed tiny fragments of lunar rock, revealing impact events spanning from about 4.33 to 1.13 billion years ago and allowing them to reconstruct more than three billion years of lunar impact history.
Dr Jourdan said understanding the Moon’s impact history could also provide important clues about Earth’s own past.
“The Moon and Earth share a common history, but the evidence of early impacts has largely disappeared from our planet,” Dr Jourdan said.
“Because the Earth and Moon formed together, every major impact recorded on the Moon tells us something about the conditions experienced by the young Earth.
“Studying lunar rocks allows us to look back billions of years and better understand the events that shaped the environments of both worlds and helps us understand the role asteroid impacts played in planetary evolution and the conditions that may have influenced the emergence of life on Earth.
“The findings come amid a new era of lunar exploration and science, with China’s Chang’e-6 mission being the first to return samples from the Moon’s far side.”
The study was led by the State Key Laboratory of Deep Earth Processes and Resources, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences.
The paper ‘The bombardment history on the lunar farside revealed by 40Ar/39Ar geochronology of Chang’e-6 impact melt rocks’, is published in Science Advances (doi/10.1126/sciadv.aee8718).
Journal
Science Advances
Method of Research
Content analysis
Subject of Research
Not applicable
Article Title
The bombardment history on the lunar farside revealed by <sup>40</sup>Ar/<sup>39</sup>Ar geochronology of Chang’e-6 impact melt rocks
Article Publication Date
23-Jul-2026
UK in pole position to lead key instrument in NASA's hunt for Earth-like worlds
image:
A conceptual design of the Habitable Worlds Observatory.
view moreCredit: NASA
UK astronomers are a step closer to playing a leading role in NASA's search for alien life in the coming decades, after receiving £3million to continue developing one of the core instruments of the Habitable Worlds Observatory (HWO).
The "exciting" mission – the US space agency's next flagship space telescope after the Nancy Grace Roman Space Telescope – is expected to launch in the 2040s.
The UK-led plans follow a series of instrument studies funded by the UK Space Agency (UKSA), which have been shared with NASA and are helping to shape the mission as it moves into its next phase of development.
"The Habitable Worlds Observatory is one of the most exciting space science missions now under development," said Professor Martin Barstow, of the University of Leicester, who is playing a leading role in the UK's involvement and gave an update on the mission at the Royal Astronomical Society's National Astronomy Meeting in Birmingham.
"It will tackle one of the biggest questions in science: are we alone in the universe? By searching for Earth-like planets and studying their atmospheres, the HWO will look for evidence of life beyond our Solar System."
Seen from a distance, a planet like Earth would be a faint dot right next to a blinding sun, 10 billion times brighter. To image this moth next to a flamethrower, HWO's 8 metre mirror must be held stable to within the width of an atom, and the light from the sun blocked out.
Professor Barstow added: "The UK has a long history of making major contributions to NASA's flagship observatories, from Hubble to the James Webb Space Telescope, and we are now in a strong position to lead the development of one of HWO's core scientific instruments."
Vincent Van Eylen, Associate Professor in Exoplanets at UCL's Mullard Space Science Laboratory, called HWO "one of the most exciting missions of my lifetime".
He added: "It will be the first telescope designed to search for evidence of life on distant planets. Imagine for a moment it finds evidence of life out there. What an achievement that would be!
"It's fantastic that the UK Space Agency is ensuring that UK scientists and engineers will have a leading role in this exciting project."
The UK is leading on the development of HWO's High Resolution Imager (HRI) and Multi-Object Spectrograph (MOS), which are expected to be core instruments on the telescope.
Researchers have just been awarded a new £3million funding boost from the UKSA to ramp up their efforts and develop the necessary technologies to make the instrument a reality. This latest development builds on the previous studies, but significantly expands the scale.
Dr Caroline Harper, Head of Space Science at the UK Space Agency, said: "This UK Space Agency funding is a significant step forward in securing the UK's place at the heart of one of the most ambitious space science missions ever conceived.
"Habitable Worlds Observatory is being designed to answer whether we are alone in the universe and will require technological advances as well as scientific breakthroughs. That's why we're backing UK scientists and engineers to lead one of its core instruments."
The UK team includes scientists from Durham University, The Open University, the University of Leicester, RAL Space, the University of Portsmouth, the University of Oxford, the UK's Astronomy Technology Centre (ATC) and UCL's Mullard Space Science Laboratory.
However, with the mission not expected to launch for another two decades, it is the existing generation of younger researchers – currently facing huge uncertainty against the backdrop of widespread funding cuts – who will be the UK's science leaders when it's ready.
"The UK Space Agency is supporting instrument development for HWO but that would be a waste if there is not a community of scientists ready to exploit it in the 2040s," Professor Barstow cautioned.
"The decisions we make over the next few years will determine whether UK scientists are at the forefront of those discoveries for decades to come."
He said sustained investment would be needed to maintain the scientific expertise and technical capability required to deliver the UK's planned contribution.
"The proposed cuts affecting key institutes and research groups involved in the mission could weaken Britain's ability to lead one of the world-leading observatory's core instruments and fully exploit the science when HWO begins operations in two decades' time," Professor Barstow added.
The HWO's headline scientific goal is to search for Earth-like planets around nearby stars and examine their atmospheres for signs of life.
But rather than surveying the entire galaxy, it will focus on nearby stars within our cosmic neighbourhood. At distances of around 30 light-years, astronomers expect the observatory to be capable of directly studying Earth-like planets and searching their atmospheres for possible signs of life.
Like the Hubble Space Telescope and James Webb Space Telescope (JWST) before it, though, HWO will also serve as a general-purpose observatory, allowing astronomers to study everything from planets and stars to galaxies and the evolution of the universe.
NASA is leading the mission, but international partners will provide major elements of the observatory. The UK aims to design and build one of the cameras that will sit at the telescope's focal plane and collect the light needed to carry out its observations, while also contributing to other systems.
Over the past three years, the UK astronomy community has held a series of national workshops, supported by the Science and Technology Facilities Council (STFC), to develop scientific priorities and bring together universities, research laboratories and industry.
UK researchers previously played important roles with the Hubble mission and led the European consortium that developed the Mid-Infrared Instrument (MIRI) on JWST.
The next phase of UK instrument studies is expected to begin next month as NASA continues developing HWO in collaboration with researchers across the world.
HWO will be the first in NASA's next generation of flagship "Great Observatories", building on the legacy of Hubble and Webb while seeking to answer one of humanity's oldest questions: whether life exists elsewhere in the universe.
ENDS
How the HWO might see the Solar System if it were at a distance of 30 light-years.
Credit
NASA
Images & video
Figure 1: A conceptual design of the Habitable Worlds Observatory.
https://drive.google.com/file/d/1x88PSxYcoZ9rJocvLud42UHIYHWddZI2/view?usp=sharing
Credit: NASA
Figure 2: A conceptual design of the Habitable Worlds Observatory.
https://drive.google.com/file/d/1J7yNZuYxHoUOUuY-frSLKuC6z1XHOGpH/view?usp=drive_link
Credit: NASA
Figure 3: A conceptual design of the Habitable Worlds Observatory, showing an 8m segmented primary mirror and off-centre secondary.
https://drive.google.com/file/d/1VUTOuKPhUvkjW34RWAWAznRtoUZcDfaZ/view?usp=drive_link
Credit: NASA
Figure 4: How the HWO might see the Solar System if it were at a distance of 30 light-years.
https://drive.google.com/file/d/1_arNMrOLWQzz84Zx5eYOBBGbKIdbxmXP/view?usp=drive_link
Credit: NASA
Video 1: A video simulation of how the Solar System would appear to HWO at 30 light-years' distance.
https://drive.google.com/file/d/1yqZTCSfKBSiY6e-SOoW8vrLksEwa0HVy/view?usp=drive_link
Credit: NASA
Further information
- NASA's 'flagship' missions are its largest and most ambitious space astronomy missions. Previous flagship observatories include the Hubble Space Telescope, Chandra X-ray Observatory, Spitzer Space Telescope, James Webb Space Telescope and the upcoming Nancy Grace Roman Space Telescope.
- The Habitable Worlds Observatory is being developed through NASA's Great Observatories Maturation Program (GOMaP), following recommendations from the 2020 US Astronomy and Astrophysics Decadal Survey.
- Funding: Development of the UK HWO programme has been supported through two separate funding streams. The Science and Technology Facilities Council has funded the UK HWO community through a programme of national workshops and related activities over the past three years. The UK Space Agency has funded the instrument concept studies that are helping to shape the UK's proposed contribution to the mission.
- NASA is expected to issue further calls for instrument studies and technology development as HWO progresses through its design phase.
- Professor Martin Barstow chairs the UK Habitable Worlds Observatory community and is coordinating UK plans for participation in the mission with the UK Space Agency and the wider UK astronomy community.
- Dr Vincent Van Eylen leads an exoplanet research team at UCL's Mullard Space Science Laboratory. He leads the UKSA-funded High Resolution Imager (HRI) team of scientists and engineers across 7 UK institutes.
- What makes HWO different from Webb? James Webb Space Telescope was designed primarily to study the early universe, galaxies, stars and planetary systems using infrared light. Habitable Worlds Observatory will also be a general-purpose observatory, but its headline science goal is the direct detection and characterisation of Earth-like planets around nearby stars in the search for evidence of life.
The session 'Habitable Worlds Observatory' will take place at NAM2026 from 14:15-15:45 BST on Friday 24 July 2026 in room M208 and M209. Find out more at: https://uobevents-national-astronomy-meeting-2026.eventsairsite.com/block-schedule. If you would like a Zoom link to watch it online, please email press@ras.ac.uk
Notes for editors
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Utilization of solar gravity perturbation in moon-aided Jovian capture
image:
Schematic diagram of dataset computation.
view moreCredit: Space: Science & Technology
Exploration interest has grown during the 20th century since Jupiter is the nearest and largest giant planet in our solar system. Currently, numerous engineers are engaged in efforts to deploy probes into the Jovian system, and some key technical research studies are also carried out for future Jovian system exploration missions. However, capturing into another planet’s system is a costly process, particularly for the Jovian system. The presence of 4 Galilean moons renders the gravity-assist technique a highly effective means of modifying the velocity of probes relative to Jupiter. However, if a Jovian moon is expected to be visited, the perijove of the spacecraft must be lower than the orbital radius of the moon. There are disadvantages to capturing with a low perijove. Firstly, the spacecraft is severely affected by the strong radiation of Jupiter, which is harmful to the electronic components on the spacecraft when it gets close to Jupiter. Secondly, an amount of fuel is consumed to raise the perijove to satisfy the requirements of subsequent objectives. In order to alleviate the disadvantages of low-perijove capture, one solution is to raise the perijove more efficiently by leveraging the solar gravity perturbation (SGP). In a research article recently published in Space: Science & Technology, scholars from Nanjing University of Aeronautics and Astronautics, Beijing Institute of Technology, and Shanghai Key Laboratory of Deep Space Exploration Technology together presents a multiple-moon-aided Jovian capture approach utilizing SGP, which can reduce the velocity increment substantially.
First, three dynamic models are introduced, and the datasets are computed, for the subsequent analysis of utilizing SGP. The four dynamic models include circular restricted 3-body problem (CR3BP), the simplified dynamical, the gravity-assist model, and the high-fidelity dynamical model. The CR3BP model is used to describe the motion of zero-mass spacecraft which utilizes SGP to change orbits with the gravitational dominance of Jupiter. In this model, the two primaries are the Sun to Jupiter which are fixed at the [−μ, 0, 0]T and [1−μ, 0, 0]T along the x axis of the rotating frame, respectively. In the simplified dynamical model, the 4 Jovian moons are assumed to move along a coplanar-circular orbit around Jupiter, and the real ephemeris is not considered. All of the trajectories are Kepler orbits in this model. In the gravity-assist model, the Jovian moon flyby is defined as a mutation of the velocity vector with the same position vector. The flyby altitude is limited to larger than 200 km. The high-fidelity dynamical model involves the gravitation of the Sun, Jupiter, Callisto, Ganymede, Europa, and Io. The J2 and J4 higher-order, spherical-harmonic expansion terms of Jupiter are also considered. Additionally, general relativity effects are included in the dynamical model. The ephemeris file are kernels in the SPICE toolkit released by NASA. Two datasets are established to investigate the mechanism of utilizing SGP. The schematic diagram of dataset computation is shown in Fig. 1. The initial position vector and velocity vector are given as the initial state of the perijove of the trajectory. The trajectory is then propagated for one revolution in the rotating coordinate system until the next perijove. Using the given parameters r, φ, and e, the initial position vector in the rotating system can be calculated by x0 = r cos(φ) + 1 − μ, y0 = r sin(φ) , z0 = 0, and the initial velocity vector can be calculated by ẋ0 = − v0 sin(φ) + r sin(φ), ẏ0 = v0 cos(φ) – r cos(φ), ż0 = 0, where v0 = [μ(1+e)/r]^(1/2). Two datasets adopt different ranges and intervals of parameters r, φ, and e. In this work, 4 stop conditions for classification are proposed in Table 3. According to different stopping conditions, the initial states in the dataset can be divided into 2 categories, which are usable and useless for this work. The categories and classification criteria for each initial state are shown in Table 4. Usable states are the first 2 in the table, and the last 3 are useless in this work.
Then, the influence of SGP is shown, and the mechanism of utilizing SGP is revealed. The mechanism of SGP in Jovian capture can be briefly summarized as Table 5.
First, for the perijove radius change in different quadrants, when the initial states are in the 2nd and 4th quadrants, the spacecraft is mainly accelerated by the cumulative solar gravity effect, which makes the perijoves higher. While the initial states are in the 1st and 3rd quadrants, the cumulative effect of the acceleration caused by SGP mainly slows down the motion and it will cause a lower perijove.
Second, when the eccentricity is closer to 1, this means that the magnitude of the initial velocity is higher and the trajectory has a higher apojove. The high apojove makes the flight time longer, so that the time of SGP is also longer, which enhances the cumulative effect on the motion of the spacecraft. Meanwhile, the higher apojove makes SGP more dominant relative to Jovian gravitation.
Third, the reason why the initial states in the 4th quadrant have a better peri-Jove raising (PJR) effect than those in the 2nd quadrant is that the apojoves of the former are in the 2nd quadrant, while the apojoves of the latter are in the 4th quadrant. Naturally, the apojoves in the 2nd quadrant are closer to the Sun than those in the 4th quadrant; thus, SGP is larger for the apojoves in the 2nd quadrant.
Finally, the designed trajectories using multiple-moon-aided capture and SGP are provided. The aim is to raise the perijove to higher than 17RJ and lower than the orbital radius of Callisto. An arrival excess velocity of 5.6 km/s is chosen. A 200-km flyby height is adopted. The flyby sequences are determined by the motion of the spacecraft from the outer to the inner Jovian system. The existence of the geometry of multiple-moon-aided capture trajectories is neglected in the preliminary analysis, but it is taken into account in the high-fidelity model. The period of the final orbit is set to 200 d. Before the first perijove arrival, the simplified dynamical and gravity-assist models are used to calculate the trajectory. A schematic diagram of the capture scenario is shown in Fig. 2. The JOI maneuver is operated at the first perijove. Once the state under the simplified dynamical model is determined, the initial state under the CR3BP model is determined. Then, SGP can be utilized to raise the perijove in the CR3BP model. A possible tangential maneuver PJR is operated to help raise the perijove at the apojove. The tangential maneuver to shorten the orbital period (SP) is operated to shorten the period of the elliptic orbit when the spacecraft reaches the perijove a second time. In the high-fidelity model, the trajectory is visualized in Figs. 17 to 19. The total velocity increment is similar with simulations under the simplified model. Some parameters in detail are listed in Table 7. The results indicate that the Jupiter Orbit Insertion (JOI) and PJR magnitudes are noticeably reduced using the method proposed in this paper. With the help of SGP, the PJR magnitude is usually less than 20 m/s, which could raise the perijove by more than 106 km.
Journal
Space: Science & Technology
Article Publication Date
31-Jul-2026
Schematic diagram of the capture scenario.
Trajectory of double-moon-aided capture.
Credit
Space: Science & Technology
Researchers uncover signatures of primordial black holes when triggering Type Ia supernovae
An international team of researchers have found when primordial black holes triggered white dwarf stars to explode as Type Ia supernovae, it may have caused a chemical abundance trend, reports a recent study published in The Astrophysical Journal on June 20.
Primordial black holes (PBH) are one of the relics from the primordial universe. During the inflation period, the primordial fluctuation of matter in the created PBHs. These black holes could be a candidate to explain the mysterious dark matter, the invisible matter that contributes to about 90% of matter in the Universe by mass. These PBHs could pass through stars across the universe. Early works suggest that, during their passage, the tidal interaction due to their own gravity could trigger the white dwarfs, a stellar evolutionary end point for low-mass stars, to explode as Type Ia supernovae (SNe Ia).
A team of researchers led by SUNY Polytechnic Institute Assistant Professor and The University of Tokyo Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) Visiting Associate Scientist Shing-Chi Leung, and including Kavli IPMU Visiting Senior Scientist Ken'ichi Nomoto and Kavli IPMU Senior Fellow Alexander Kusenko, studied the dynamical, optical, and chemical characteristics of supernovae under this new PBHs-triggered explosion channel.
In an earlier paper published in 2025 by the team, the PBH-triggered explosions can actually produce SNe Ia that closely resemble the standard SNe Ia models.
In this new study, the researchers did a comparative study with supernova remnants (Tycho, Kepler, 3C 397), nearby supernovae (e.g., SN 2011fe, SN 2012cg) and the chemical abundances of Milky Way stars. They showed PBH-triggered SNe Ia could explain several observed characteristics of these objects. By examining the radioactive isotopes such as Ni-56, Ni-57, and stable elements such as Mn and Ni, the team pinned down the masses and the metallicities (the amount of metal when the star is formed, which probes when the star is born in the cosmic age) of the progenitor stars of these supernova events and remnants.
Furthermore, the supernova model to study how this explosion channel was involved in the galactic chemical enrichment showed that a non-zero fraction of PBH-triggered SN Ia is necessary to explain the chemical abundance trend made by stars in the Milky Way.
“Our work suggests that some supernova that we observe in the sky could be a result of the PBHs. Therefore, even though we cannot directly observe these evasive entities, they leave many interesting clues in nature for us to probe their properties.” Leung said.
The team will continue to expand the research scope to study how these supernovae change the population of canonical supernovae and the collective rates of these transient events.
Journal
The Astrophysical Journal
Article Title
Primordial Black Hole Triggered Type Ia Supernovae II: Comparison with Supernova Remnants and Galactic Chemical Evolution
