New contracts highlight growing global appetite for real-time geospatial intelligence
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An industry coalition is asking congressional appropriators to reject the administration’s proposal to terminate the Commerce Department’s space traffic coordination system.
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Former Space Development Agency official Paula Trimble has joined the company as vice president of government affairs and strategy
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It wasn’t until the second year of my undergraduate degree that someone finally put a name to why I’d been struggling with day-to-day things throughout my life – it was Attention Deficit Hyperactivity Disorder (ADHD). It explained so much; my extreme anxiety around work and general life, my poor time management, the problems I had regulating my emotions, and my inability to manage everyday tasks. Being able to put a label on it, and therefore start taking steps to mitigate the worst of its symptoms, was a real turning point in my life.
As such, when I started my PhD at the Quantum Engineering Centre for Doctoral Training at the University of Bristol, I got on the (notoriously long) waiting list for an assessment and formal diagnosis. I knew that because of my ADHD, my PhD journey would look a little different compared to the average student, and that I’d have to work harder in some aspects to mitigate the consequences of my symptoms.
People with ADHD exhibit a persistent pattern of inattention, hyperactivity and/or impulsivity that interferes with day-to-day life. It is a type of neurodivergence – when someone’s brain functions in a different way to what is considered “typical”. Other neurodivergent conditions include autism, dyslexia and dyspraxia, but the term also encompasses mental-health issues, learning difficulties and acquired neurodivergence (for example, after a brain injury).
According to Genius Within, at least 5% of the population have ADHD, 1–2% are autistic, 14% have mental health needs, and many more have other neurodevelopmental conditions. It is also common for those with one neurodivergence to have one or more other co-occurring neurodivergent conditions.
However, if you look specifically at the scientific community, these percentages are much higher. For example, in a 2024 survey “Designing Neuroinclusive Laboratory Environments” run by HOK, it was found that out of 241 individuals, 18.6% had ADHD and 25.5% were autistic. If neurodivergent people remain highly overrepresented in the sciences, then it is imperative that we understand and accommodate for the needs of these individuals in work and research environments.
One common trait among neurodivergent people is that they have greater strengths and bigger weaknesses across skillsets when compared to neurotypical people. This is known as having a “spiky profile” – it appears as peaks and troughs above and below a “normal” baseline (figure 1). The skillsets commonly included in a profile are analytical, mathematical, motor, situational and organizational skills; relationship management; sensory sensitivities; processing speed; verbal and visual comprehension; and working memory. So while neurodivergent people may be extremely capable at certain skills, they may really struggle with others.
A neurodivergent person will have what is known as a “spiky profile” because they can find some cognitive skills easy (peaks) but struggle with others (troughs). Every person has an individual profile – even if two people have the same neurodivergent condition, they will have different strengths and weaknesses.
This example compares a neurodivergent profile (red) with a neurotypical one (green) and an average (dashed), for a small set of cognitive skills;
Personally, I have problems with working memory, organization and processing speed, but each of these issues present differently in certain situations. For example, it’s not uncommon for me to reach the end of a meeting with my supervisor and feel that I understand all that was discussed and have no questions – but then I may come up with some important queries sometime later that didn’t occur to me at the time. This demonstrates a difference in processing speed, which thankfully can be accommodated for by maintaining an open line of communication between myself and my supervisors.
Meanwhile, for Daisy Shearer – who leads the outreach and education programme at the National Quantum Computing Centre (NQCC) in the UK – their autism affects their day-to-day life in other ways. “I experience sensory inputs and emotion regulation differently to neurotypical people, which uses a lot of energy to manage,” Shearer explains. “My executive functioning skills [those that help you manage everyday tasks] tend to be poor, as well as my social skills, which I work hard to overcome.”
Despite our different neurotypes, Shearer and I also have some symptoms in common. For example, we both struggle with switching between tasks, and time blindness, which means we have difficulty in perceiving and managing time. But while many traits can overlap between neurotypes in this way, even two individuals with the same diagnosis won’t have the exact same symptoms or profile.
Abilities and sensitivities can fluctuate day-to-day or even hour-to-hour, regardless of the accommodations and strategies in place
Furthermore, neurodivergent people can be “dynamically disabled”, meaning that our abilities and sensitivities fluctuate day-to-day or even hour-to-hour, regardless of the accommodations and strategies in place. Shearer, for instance, used to be primarily lab-based and would find that environment soothing, but occasionally the lab would become overwhelming when their sensory profile shifted.
Meanwhile for me, one day I may be able to focus and complete multiple large tasks in a day, attend various meetings and answer e-mails in a timely fashion. But on another day – sometimes even the next day – I may only be able to answer half of my e-mails and will flit between tasks, unable to focus deeply on any one thing. This can make monitoring progress and completing milestones difficult, and requires a high degree of flexibility and understanding from those around me.
So what can the physics community do to help people who are neurodivergent like myself? While we absolutely don’t want to be treated leniently – we want our work as physicists to be as high a standard as anyone else’s – working with individuals to accommodate them correctly is key to helping them succeed.
That’s why in 2019 Shearer founded Neuroinclusion in STEM, after having no openly autistic role models in their physics career to date. The project, which is community-driven, aims to increase the visibility of neurodivergent people in science, technology, engineering and mathematics (STEM), and provide information on best practices to make the fields more inclusive.
Shearer also takes part in many equality, diversity and inclusion (EDI) committees, and gives talks at conferences to highlight how the STEM community can improve the working environment for its neurodivergent members.
Indeed, Shearer’s own set up at the NQCC is a great example of workplace accommodations helping an employee thrive. Firstly, Shearer had a high level of autonomy in defining their role when they joined the NQCC. “It was incredibly helpful when it comes to managing how my brain works,” they explain. Shearer also has the flexibility to work from home if they’re feeling particularly sensory sensitive, and were consulted in the design of the NQCC’s “wellbeing room” – a fully sensorily controllable space that they can use during their work day when feeling overwhelmed by sensory stimuli. Other, small adjustments that have helped include having an allocated desk away from general people-traffic, and colleagues being educated to ensure a more inclusive environment.
For physicists working in a lab – dependent on health and safety measures – it can help to wear headphones or earplugs and have dimmable lights to minimize sensory inputs. Some neurodivergent people also benefit from visual aids and written instructions for experiments and equipment. Personally, as a theorist in an office, I find noise cancelling headphones, and asking colleagues to consider e-mailing rather than interrupting me at my desk, can help reduce distractions.
While education and accommodations are key, it’s also important to remember the strengths that come with having a neurodivergent spiky profile – the peaks, so to speak. “I have strong analytical, communication and creative skills,” explains Shearer, “which make me very good at what I do professionally.”
For me, I excel in visual, written and communication skills, and try to use these to my advantage. I’m good at spotting errors in mine and others’ work, I’m a concise but detailed writer, and when not working on my PhD, I’m trying to communicate complex ideas in quantum physics to different audiences with varying degrees of understanding of physics and science.
By recognizing all of our unique capabilities and adequately accommodating those additional neurodivergent struggles, we can build systems that empower instead of limit us
Reminding myself of these strengths is key, as it can be too easy to focus on the negatives that come with being neurodivergent. By recognizing all of our unique capabilities and adequately accommodating those additional neurodivergent struggles, we can build systems that empower instead of limit us.
I believe Shearer put this best: “By embracing our individual strengths, we can enable everyone to thrive in their professional and personal lives, but that can only come with understanding how to accommodate each other.”
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A team of researchers in Sweden has demonstrated how smart optical metasurfaces can respond far more strongly to incoming light when switched to their conducting states. By fine-tuning the spacing between arrays of nanoantennae on a polymer metasurface, Magnus Jonsson and colleagues at Linköping University were able to generate nonlocal electromagnetic coupling between the antennae – vastly strengthening the metasurface’s optical responses.
Metasurfaces are rapidly emerging as a key component of smart optical devices, which can dynamically manipulate the wavefronts and spectral signals of incoming light. “They work in a way that nanostructures are placed in patterns on a flat surface and become receivers for light,” Jonsson explains. “Each receiver, or antenna, captures the light in a certain way and together these nanostructures allow the light to be controlled as you desire.”
One promising route towards such intelligent metasurfaces is to fabricate their antennae from conducting polymers, such as PEDOT. In such materials, the intrinsic permittivity – which determines how the material responds to electric fields, such as those from incoming light – can be manually switched by altering the oxidation state through a redox reaction. This, in turn, modifies the polymer’s carrier density and mobility, altering the number and behaviour of mobile charge carriers that contribute to its optical properties.
A key measure of how well these materials resonate with light is the “quality factor”, which describes how sharp and long-lived a resonance is. A higher quality factor signifies a stronger, more precise interaction with light, while a lower value indicates weaker and broader responses.
When PEDOT is in its metallic oxidation state, incident light will drive the resonance of surface plasmons: collective oscillations of mobile charges that are confined near the surface of the material. At specific wavelengths, these plasmons can strongly enhance electromagnetic fields – altering properties including the phase, amplitude and spectral composition of the light reflected and transmitted by the metasurface.
Alternatively, when PEDOT is switched to its insulating state, the resulting lack of available charge carriers will significantly suppress surface plasmon formation, leading to diminished optical response.
In principle, this effect offers a useful way to modulate the nanoantennae of smart metasurfaces via redox reactions. So far, however, the surface plasmons generated through this approach have only resonated weakly in response to incident light, and have quickly lost their energy after excitation – even when the polymer is switched to its metallic state. This has made the approach impractical for use in smart, switchable metasurfaces that require strong and coherent plasmonic behaviour.
Jonsson’s team addressed this problem by considering the spacing of PEDOT nanoantennae within periodic arrays. When separated at precisely the right distance, the array generated nonlocal coupling through coherent diffractive interactions – involving the constructive interference of light scattered by each antenna.
As a result, this arrangement supported collective lattice resonances (CLRs) – in which entire arrays of nanoantennae respond collectively and coherently to incident light. This drastically boosted the strength and sharpness of the material’s plasmonic response, boosting its quality factor by up to ten times that of previous conducting polymer nanoantennae. Such high-quality resonances indicate more coherent, longer-lived plasmonic modes.
As before, the researchers could manually switch the nanoantenna array between metallic and insulating states via redox reactions, which reversibly weakened its plasmonic responses as required. This dynamic tuning offers a pathway towards electrically or chemically programmable optical behaviour.
Based on this performance, Jonsson’s team is now confident that this approach could have promising implications for the future of smart optical metasurfaces. “We show that metasurfaces made of conducting polymers seem to be able to provide sufficiently high performance to be relevant for practical applications,” says co-author Dongqing Lin.
For now, the researchers have demonstrated their approach across mid-infrared wavelengths. But with some further tweaks to their fabrication process, allowing for closer spacings between the nanoantennae and smaller antenna sizes, they aim to generate CLRs in the visible spectrum. If achieved, this could open up new opportunities for smart optical metasurfaces in cutting-edge optical applications as wide-ranging as holography, invisibility cloaking and biomedical imaging.
The study is described in Nature Communications.
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I recently heard a physicist jocularly remind us that “All science is either physics or stamp collecting”. Widely attributed to the Nobel prize-winning nuclear physicist Ernest Rutherford, this quotation is often interpreted as the pre-eminence of physics over other scientific disciplines. While there is some doubt about whether Rutherford actually uttered that phrase, what’s interesting for me is not its origins but why the statement has – or ought to have – little place in today’s world.
In an era of rapid technological advancement and complex global challenges, it has never been more important for the scientific community to work together. From tackling climate change and dealing with the opportunities and risks of artificial intelligence to exploring space and ensuring everyone has advanced and accessible healthcare, we need experts from different disciplines to work together. No single domain can comprehensively address such challenges.
That’s why all of us in Science, Technology, Engineering, Mathematics and Medicine (STEMM) need to work together collectively and with one voice. Fortunately, there are many examples of where this already occurs. Biomedical engineering, for example, has seen physicists, chemists, biologists, material scientists and medical experts develop many successful innovations, such as prosthetics, joint implants, artificial organs and advanced imaging technologies.
The development of machine learning algorithms for healthcare applications, meanwhile, requires computer scientists, statisticians and medical professionals. By embracing collaboration, the strengths of multiple disciplines can be exploited to drive innovation and create solutions that would be difficult – and sometimes even impossible – to achieve in isolation
Without such collaboration, any solution would be incomplete and likely impractical. By working together, STEMM professionals are creating holistic solutions that address our technical, environmental and societal needs. However, it’s vital that we share knowledge and expertise so that STEMM professionals can learn from one another and build on existing work.
In today’s ever-changing world, staying informed about the latest developments is critical. Collaborative efforts ensure that knowledge is disseminated quickly and efficiently, thereby reducing duplication of effort and speeding up progress. It also fosters creativity by encouraging individuals to think beyond the boundaries of their own expertise. Innovation often occurs at the intersection of disciplines.
When people from different fields collaborate, they bring unique perspectives and methodologies that can lead to ground-breaking discoveries. Just look at the Human Genome Project (HGP), which involved teams of researchers working together to achieve a common goal. The HGP was a voyage of biological discovery led by an international group of researchers looking to comprehensively study all the DNA of a select set of organisms.
Launched in October 1990 and completed in April 2003, the HGP’s major accomplishment – generating the first sequence of the human genome – provided fundamental information about the human blueprint, which has since accelerated the study of human biology and improved the practice of medicine. What we need are more such projects where people work together towards a common goal.
Competition and siloed thinking can, however, hinder progress. Individuals and companies may be reluctant to share knowledge or resources due to concerns about leaking intellectual property, not getting recognition or losing funding opportunities. But knowledge needs to be spread, not least because vesting know-how in a single individual is risky if that person leaves an organization. When you share knowledge, you never know what it can lead to.
Collaborative teams with people from different disciplines are better equipped to handle setbacks and challenges as, when faced with obstacles, team members can rely on each other for support and help seeking alternative solutions. Collective resilience is important in STEMM fields, where failure is often a stepping stone to success. Ultimately the progress and success of humanity depends on our ability to work together.
In practical terms, I am pleased to say that the Institute of Physics (IOP) Business Innovation Awards, which have been running for almost 15 years, embrace much of what I have been talking about. They recognize and celebrate small, medium and large companies that have excelled in innovation, delivering significant economic and/or societal impact through the application of physics.
Whilst the award-winning product innovations recognized by the IOP need to have some link to physics, they almost always involve some other fundamental science. What’s more, the innovations invariably need input from engineering design and manufacture, from software development, and from expertise in, say, medicine, aerospace, nuclear power or food science. Successful winners demonstrate strong multidisciplinary collaboration within their teams.
The bottom line is that’s vital for STEMM professionals to stick together and not try to trump each other with statements like Rutherford’s. For collaboration to work effectively, it requires mutual respect across all contributors. And by working well together, we will drive innovation, help solve complex problems, and shape a better future for the world. As a physicist by training, I naturally have a certain loyalty to the subject. But I’m hugely grateful for what I’ve learnt and achieved by working with people from other disciplines.
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The European Space Agency has selected five launch vehicle startups to proceed to the next phase of a competition where they could receive contracts for satellite launches and upgraded vehicles.
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Despite its inclusion in the official French name — le Salon International de l’Aéronautique et de l’Espace — the Paris Air Show traditionally has not highlighted space in its panels or exhibitions. The focus of the event has stayed on commercial and military aviation as companies showed off aircraft and announced new orders. This year’s […]
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Scientists are proposing China’s first ice giant mission, aiming to launch a radioisotope-powered spacecraft to orbit Neptune and study its enigmatic moon Triton.
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A new microscope inspired by the design of Keplerian telescopes produces much sharper images from luminescence from biological cells than was possible with previous devices. Dubbed the “QIScope” by its creators, the device’s highly sensitive camera can detect extremely low levels of light and could be used to observe delicate biostructures in greater detail and over longer periods of time without damaging them.
Many organisms naturally produce light via special enzymes in their cells. Although most such bioluminescent creatures are found in the ocean – think of anglerfish and firefly squid – there are also examples of terrestrial bioluminescent organisms, including bacteria and molluscs.
For researchers in life sciences, harnessing this light is an attractive alternative to imaging organisms using fluorescence. This is because it does not rely on strong external illumination, which can damage cells or interfere with the subtle signals they produce. The downside is that bioluminescence is feeble by comparison, so using it produces relatively low-resolution images.
Researchers led by Jian Cui of Helmholtz Munich and the Technical University of Munich, Germany, have now used a new detector technology called a quantum image sensor (QIS) to improve the resolution of bioluminescence imaging. By integrating this sensor into an unconventional optical microscope design, they increased the number of photons per pixel without sacrificing spatial resolution or field-of-view (FOV), as previous bioluminescence microscopes did.
To avoid this restriction, which is known as vignetting, Cui explains that the team separated the two lenses and inserted a Keplerian telescope between them. “This ‘telescope-within-a-microscope’ reshapes the output of the objective lens to match the width of the tube lens’ back aperture,” he says.
The resulting “QIScope”, as the researchers call it, substantially reduces the size of the image while still capturing the full FOV. The result: an instrument with a higher signal-to-noise ratio and spatial resolution, leading to crisper images than was possible before.
“New detector technologies are being developed all the time and some of them are very impressive,” Cui says. “However, we shouldn’t think about simply putting cameras on microscopes – sometimes you need to design the microscope around the properties of the camera. And this is what we have done.”
The researchers, who detail their work in Nature Methods, hope it will spur more interest in bioluminescence as an imaging tool. “There is a lot of untapped potential here and it could have advantages for certain applications such as studying photosensitive samples or low-abundance proteins,” Cui tells Physics World. “It could be used to study a range of biological systems – from single cells to organoids and tissue models. And since it can be used for long periods, it could reveal subtle and long-term changes in cell behaviour, so supporting progress in diverse research areas, including cell biology, disease modelling and drug discovery.”
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President Donald Trump says it would have been “inappropriate” for Jared Isaacman to lead NASA given his ties to Elon Musk and history of political donations.
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The pads were intended to support the Air Force’s Rocket Cargo program
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The canceled program, known as Protected Tactical Satellite Communication-Resilient (PTS-R), was launched in 2020 to build anti-jam communications satellites
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A physicist from Vilnius University in Lithuania has created a 3D-printed replica of the Sorbonne Chapel so small it fits on a human hair.
Located in Paris’s Latin Quarter, the Chapel of Sainte-Ursule de la Sorbonne is a Roman Catholic chapel and was constructed in the 17th century.
To create the structure, Gordon Zyla, who carries out research in light technologies at Vilnius’s Laser Research Centre, used a laser nanofabrication technique known as multiphoton 3D lithography.
“Unlike conventional 3D printing, this approach can solidify a light-sensitive material at virtually any point in space, enabling the fabrication of truly 3D structures,” notes Zyla.
The length of the finished product is approximately 120 micrometres long, being 275,000 times smaller than the original yet still preserving its architectural details.
Late last week, the model was presented as a symbolic gift to Sorbonne University president Nathalie Drach-Temam during a visit to Vilnius.
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The ESS satellites are central to U.S. nuclear command, control and communications
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Damage to the spinal cord can disrupt communication between the brain and body, with potentially devastating effects. Spinal cord injuries can cause permanent loss of sensory, motor and autonomic functions, or even paralysis, and there’s currently no cure. To address this inadequacy, researchers at Chalmers University of Technology in Sweden and the University of Auckland in New Zealand have developed an ultrathin bioelectric implant that improved movement in rats with spinal cord injuries.
The implant works by delivering a low-frequency pulsed electric field (EF) across the injury site – an approach that shows promise in promoting regeneration of axons (nerve fibres) and improving outcomes. Traditional EF treatments, however, rely on metal electrodes that are prone to corrosion. In this latest study, described in Nature Communications, the researchers fabricated stimulation electrodes from sputtered iridium oxide films (SIROF), which exhibit superior durability and stability to their metal counterparts.
The team further enhanced the EF treatment by placing the electrodes directly on the spinal cord to deliver stimulation directly to the injury site. Although this subdural positioning requires more invasive surgery than the epidural placement used previously, it should deliver stronger stimulation while using an order of magnitude less power than epidural electrodes.
“We chose subdural stimulation because it avoids the shunting effect of cerebrospinal fluid, which is highly conductive and can weaken the electric field when electrodes are placed epidurally,” explains co-lead researcher Lukas Matter from Chalmers University of Technology. “Subdural placement puts the electrodes directly on the spinal cord, allowing for stronger and more precise stimulation with lower current.”
Matter and collaborators tested the implants in rats with spinal cord injuries, using 200 μm diameter SIROF electrodes placed on either side of the injury site. The animals received 1 h of EF treatment daily for the first 7–11 days, and then on weekdays only for up to 12 weeks.
To compare EF treatment with natural healing (unlike humans, rats can recover after spinal cord injury), the researchers assessed the hind-limb function of both treated and non-treated rats. They found that during the first week, the non-treated group recovered faster than the treated group. From week 4 onwards, however, treated rats showed significantly improved locomotion and coordination compared with non-treated rats, indicating greater recovery of hind-limb function.
The treated rats continued to improve until the end of the study (week 12), while non-treated rats showed no further improvement after week 5. At week 12, all of the treated animals exhibited consistent coordination between front and hind limbs, compared with only 20% of non-treated rats, which struggled to move smoothly.
The team also assessed the recovery of mechanical sensation by touching the animals’ paws with a metal filament. Treated rats withdrew their paws faster than non-treated rats, suggesting a recovery of touch sensitivity – though the researchers note that this may reflect hypersensitivity.
“This indicates that the treatment supported recovery of both movement and sensation,” says co-lead researcher Bruce Harland from the University of Auckland in a press statement. “Just as importantly, our analysis confirmed that the treatment did not cause inflammation or other damage to the spinal cord, demonstrating that it was not only effective but also safe.”
To confirm the superior stability of SIROF electrodes, the researchers performed benchtop tests mimicking the in vivo treatment. The SIROF electrodes showed no signs of dysfunction or delamination, while platinum electrodes corroded and failed.
“Platinum electrodes are prone to degradation over time, especially at high charge densities, due to irreversible electrochemical reactions that cause corrosion and delamination, ultimately compromising their long-term stability,” says Matter. “SIROF enables reversible charge injection through surface-bound oxidation states, minimizing the generation of potentially toxic stimulation byproducts and enhancing their stimulation capabilities.”
In contrast with previous studies, the researchers did not see any change in axon density around the lesion site. Matter suggests some possible reasons for this finding: “The 12-week time point may have been too late to capture early signs of regeneration. The injury itself created a large cystic cavity, which may have blocked axon growth. Also, electric field treatment might improve recovery through protective or alternative mechanisms, not necessarily by promoting new axon growth”.
The researchers are now developing an enhanced version of the implant with larger electrodes based on the conductive polymer PEDOT, which enables higher charge densities without compromising biocompatibility. This will allow them to assess a broader range of field strengths and pulse durations in order to determine the optimal treatment conditions. They also plan to test the implant in larger animal models, and hope to elucidate the mechanisms underlying the locomotion improvement using ex vivo models.
As for the possibility of future clinical implementation, senior author Maria Asplund of Chalmers University envisions a temporary, possibly biodegradable, subdural implant that safely delivers low-frequency EF therapy. “This could be implanted early after spinal cord injury to support axon regrowth and reduce the follow-up damage that occurs after the injury itself,” she tells Physics World.
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Scientists in Switzerland and Japan have uncovered what they say is the first direct evidence that materials at the bottom of the Earth’s mantle flow like a massive river. This literally “ground-breaking” finding, made by comparing seismic data with laboratory studies of materials at high pressures and temperatures, could reshape our understanding of the dynamics at play deep within our planet’s interior.
For over half a century, one of the greatest unresolved mysteries in geosciences has been a phenomenon that occurs just above the boundary where the Earth’s solid mantle meets its liquid core, says Motohiko Murakami, a geophysicist at ETH Zurich who led the new research effort. Within this so-called D” layer, the velocity of seismic waves passing through the mantle abruptly increases, and no-one is entirely sure why.
This increase is known as the D” discontinuity, and one possible explanation for it is a change in the material the waves are travelling through. Indeed, in 2004, Murakami and colleagues at the Tokyo Institute of Technology’s department of earth and planetary sciences suspected they’d uncovered an explanation along just these lines.
In this earlier study, the researchers showed that perovskite – the main mineral present in the Earth’s lower mantle – transforms into a different substance known as post-perovskite under the extreme pressures and temperatures characteristic of the D” layer. Accordingly, they hypothesized that this phase change could explain the jump in the speed of seismic waves.
Nature, however, had other ideas. “In an experimental study on seismic wave speeds across the post-perovskite phase transition we conducted three years later, such a sharp increase in velocity was not observed, bringing the problem back to square one,” Murakami says.
Subsequent computer modelling revealed a subtler effect at play. According to these models, the hardness of post-perovskite materials is not fixed. Instead, it depends on the direction of the material’s crystals – and seismic waves through the material will only speed up when all the crystals point in the same direction.
In the new work, which they detail in Communications Earth & Environment, Murakami and colleagues at Tohoku University and the Japan Synchrotron Radiation Research Institute confirmed this in a laboratory experiment for the first time. They obtained their results by placing crystals of a post-perovskite with the chemical formula MgGeO3 in a special apparatus designed to replicate the extreme pressures (around 1 million atmospheres) and temperatures (around 2500 K) found at the D” depth nearly 3000 km below the Earth’s surface. They then measured the velocity of lab-produced seismic waves sent through this material.
These measurements show that while randomly-oriented crystal samples do not reproduce the shear wave velocity jump at the D” discontinuity, crystals oriented along the (001) slip plane of the material’s lattice do. But what could make these crystals line up?
The answer, Murakami says, lies in slow, convective motions that cause the lower mantle to move at a rate of several centimetres per year. “This convection drives plate tectonics, volcanic activity and earthquakes but its effects have primarily been studied in the shallower region of the mantle,” he explains. “And until now, direct evidence of material movement in the deep mantle, nearly 3000 km beneath the surface, has remained elusive.”
Murakami explains that the post-perovskite mineral is rigid in one direction while being softer in others. “Since it naturally aligns its harder axis with the mantle flow, it effectively creates a structured arrangement at the base of the mantle,” he says.
According to Murakami, the discovery that solid (and not liquid) rock flows at this depth does more than just solve the D” layer mystery. It could also become a critical tool for identifying the locations at which large-scale mantle upwellings, or superplumes, originate. This, in turn, could provide new insights into Earth’s internal dynamics.
Building on these findings, the researchers say they now plan to further investigate the causes of superplume formation. “Superplumes are believed to trigger massive volcanic eruptions at the Earth’s surface, and their activity has shown a striking correlation — occurring just before two major mass extinction events in Earth’s history,” Murakami says.
Being able to understand – and perhaps even predict – future superplume activity could therefore “provide critical insights into the long-term survival of humanity”, he tells Physics World. “Such deep mantle processes may have profound implications for global environmental stability,” he says. “By advancing this research, we aim to uncover the mechanisms driving these extraordinary mantle events and assess their potential impact on Earth’s future.”
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Congress approved a budget reconciliation bill that includes nearly $10 billion for NASA human spaceflight programs and could also lead to the transfer of a space shuttle to Houston.
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China sent a new satellite into orbit for its experimental Shiyan series Thursday with a launch from the country’s southwest.
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