It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Saturday, November 02, 2024
Landmark 20-year study of climate change impact on permafrost forests
Data could help rethink climate change models regarding sources of carbon and CO2 sinks
Osaka Metropolitan University
image:
The tower installed in a black spruce forest on permafrost in Fairbanks, Alaska, monitors CO2 exchange and environmental conditions in 30-minute intervals.
In perhaps the first long-term study of CO2 fluxes in northern forests growing on permafrost, an Osaka Metropolitan University-led research team has found that climate change increased not only the sources of carbon, but also the CO2 sinks.
The 20-year observation from 2003-2022 in the interior of Alaska showed that while CO2 sinks turned into sources during the first decade, the second decade showed a nearly 20% increase in CO2 sinks.
Graduate School of Agriculture Associate Professor Masahito Ueyama and colleagues found that warming led to wetness, which in turn aided the growth of black spruce trees. During photosynthesis, the growing trees were using the increasing CO2 released from human activities.
“The 20 years of observational data that we have is, as far as we know, the longest record of such research on permafrost forests in the world,” Professor Ueyama proclaimed. “However, since it is difficult to apply the findings and data from those 20 years to a future world in which warming continues, further long-term observations are needed. But we hope that our findings will help verify and improve the accuracy of warming prediction models.”
The findings are published in the Proceedings of the National Academy of Sciences.
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About OMU
Established in Osaka as one of the largest public universities in Japan, Osaka Metropolitan University is committed to shaping the future of society through “Convergence of Knowledge” and the promotion of world-class research. For more research news, visit https://www.omu.ac.jp/en/ and follow us on social media: X, Facebook, Instagram, LinkedIn.
Anomalous wet summers and rising atmospheric CO2 concentrations increase the CO2 sink in a poorly drained forest on permafrost
Less car use and more plane travel: how energy consumption related to transport has changed since the pandemic
A study examines changes in mobility patterns in Europe during and after the pandemic
Universitat Oberta de Catalunya (UOC)
Living with a mask stuck to your face, only leaving the house to go to the supermarket, not using the bus or the commuter train... The COVID-19 pandemic triggered sudden and far-reaching social changes worldwide, not only because of measures to protect people against the virus but also as a result of the policies applied by governments to curb the spread of the virus and reduce the impact of the disease on the health system. Four and a half years have gone by since the WHO declared a health emergency and, thanks to vaccines, we have learned to live with the virus. While some changes have stayed with us, others have been quickly forgotten.
In recent years, many studies have sought to analyse the impact of these changes. Now, a research project led by Helena Patiño examines changes in energy consumption in the European transport sector during and after the pandemic. Patiño is a PhD student on the Society, Technology and Culture programme and member of the Sustainability, Management and Transport Research Group (SUMAT) in the Universitat Oberta de Catalunya (UOC) Faculty of Economics and Business. She is being supervised by Professor Pere Suau, who also carried out research at the Universitat Autònoma de Barcelona Institute of Environmental Science and Technology (ICTA-UAB). Their work has led to the recent publication of an article with Lewis C. King and Iván Savin, both researchers at ICTA-UAB.
The paper, available in open access, concludes that during the worst of the pandemic there were significant and widespread reductions in the use of motorized land transport, both individual and collective, and in the use of aviation. However, recovery patterns have been different across the continent. "Overall, Europeans have reduced car use since the pandemic, but have flown much more frequently. However, trends vary considerably between countries. Some have resumed previous transport patterns, while others have managed to maintain a moderate reduction in transport use," said Patiño.
Has the pandemic changed the way we get around?
Mobility is in the spotlight of all climate policies. As stated in the article, transport still relies heavily on fossil fuels, accounting for around 37% of emissions of human-generated carbon dioxide (CO2, the main greenhouse gas) worldwide. Strategies for reducing emissions, such as the European scheme for a 55% reduction by 2030, have one of their main areas of action in the transition towards low-emission mobility, with measures including the electrification of transport and the promotion of collective transport such as trains and buses. For all of them, a change in people's behaviour is essential.
The first two years of the pandemic provided a unique opportunity to study changes in people's travel habits. Travel decreased sharply with lockdowns and border closures but, after the relaxation of control measures, people did not completely return to their old habits. For example, as detailed in the paper, a survey in the United Kingdom found that Britons were willing to reduce the number of flights they took by 20-26% and car journeys by 24-30%. However, such data do not reflect in detail the extent to which the pandemic has changed mobility patterns in Europe.
"Achieving lasting changes in people's behaviour is not easy. Governments should support environmentally friendly transport options, such as bicycles and electric cars, and lead campaigns to change behaviour, so that sustainable transport is not just an option, but the preferred choice for everyone," said Patiño, who has also published an article in The Conversation Europe on this issue. "In the post-pandemic era, this could mean expanding the cycling infrastructure, making public transport more affordable, and supporting remote work and local outdoor activities."
An uneven recovery: lessons from Sweden, Denmark and the Czech Republic
Following the gradual lifting of pandemic restrictions, Europeans' transport habits have evolved unevenly. According to the study, in some countries, such as Austria, Germany and the United Kingdom, the use of planes and cars remained below normal after restrictions were lifted, but the changes weren't major. Other countries, where COVID-19 policies were stricter, like Greece, Portugal, Italy and Spain, experienced a notable rebound in flying and the use of land transport (road and rail). This increase, the researchers say, could also be influenced by the attractiveness of Mediterranean destinations for international tourists.
However, the study reveals that some of the changes that occurred during the pandemic have been maintained in three countries: Sweden, Denmark and the Czech Republic. "Sweden already had a relatively high percentage of remote workers before the pandemic, but the number has continued to grow since then. Furthermore, since 2010, the country has been promoting outdoor leisure activities, facilitating access to places of natural beauty and promoting outdoor exercise," Patiño added. "Denmark, in turn, has continued to invest in cycling infrastructure and electric bicycles. A recent survey found that Copenhagen residents are cycling to work more than before the pandemic."
In the Czech Republic, measures to reduce fares on public transport helped encourage cleaner transport options after restrictions were lifted. Getting around on foot has also gained popularity: the number of pedestrian journeys in Prague has increased by 10% since 2016. "The overall results indicate that there is unlikely to be a uniform change in behaviour towards less travel across Europe," Patiño said. "However, important lessons can be learned from countries that do show lasting effects, as their transport and energy policies may have contributed to these outcomes."
This UOC research project contributes to United Nations Sustainable Development Goal (SDG) 13: Climate Action - take urgent action to combat climate change and its impacts.
UOC R&I
The UOC's research and innovation (R&I) is helping overcome pressing challenges faced by global societies in the 21st century by studying interactions between technology and human & social sciences with a specific focus on the network society, e-learning and e-health.
Over 500 researchers and more than 50 research groups work in the UOC's seven faculties, its eLearning Research programme and its two research centres: the Internet Interdisciplinary Institute (IN3) and the eHealth Center (eHC).
The university also develops online learning innovations at its eLearning Innovation Center (eLinC), as well as UOC community entrepreneurship and knowledge transfer via the Hubbik platform.
Open knowledge and the goals of the United Nations 2030 Agenda for Sustainable Development serve as strategic pillars for the UOC's teaching, research and innovation. More information: research.uoc.edu.
Since wolves returned to Germany 20 years ago, they have spread quickly in many parts of the country. The rapid increase in the number of wolves was due to high survival and reproduction rates in areas with favourable environmental conditions. This is the result of an analysis carried out by the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) in collaboration with the LUPUS Institute, the Federal Agency for Nature Conservation (BfN), and the Senckenberg Center for Wildlife Genetics. The probability of survival for wolves during the period analysed was higher than anywhere else in the world. However, the expansion phase will end as soon as the carrying capacity of suitable German landscapes are reached – at which point survival rates can be expected to fall, according to the scientific team in a new paper in the scientific journal Wildlife Biology.
Young wolves in Germany had an annual survival probability of 75 percent during the first two decades since the beginning of the recolonisation of Germany; for adult wolves it was as high as 88 percent. For young wolves up to the age of two years, the variation in survival rate depended on the suitability of the habitat – the less suitable it was for wolves, the lower their survival; for adult wolves, such a relationship could not be established by the scientific team led by the Department of Ecological Dynamics at the Leibniz-IZW. “Using survival analysis, we were able to determine the median survival time of a wolf in Germany to be 146 weeks, which is around three years”, says Prof Dr Stephanie Kramer-Schadt, head of the Leibniz-IZW department and professor at the Technische Universität Berlin. The highest recorded longevity of a wolf in the study dataset was almost 13 years.
“The survival rates of the German wolf population were very high compared to other regions, in fact they were among the highest in the world”, Kramer-Schadt continued. “This indicates that the wolves settled in habitats that were very suitable for them during the 20 years which we analysed in this paper. Strict legal protection has also contributed to high survival rates.” Landscapes that qualify as suitable are those that offer sufficient cover – for example by forest cover – and areas that are as far away from roads as possible. These areas allow wolves to avoid humans and can serve as refuge for the animals. If wolves settle in less suitable habitats, this reduces their survival and reproduction. “While adult animals can still survive and establish territories in less suitable areas, the lower survival rate of young and sub-adult wolves and the lower number of young per litter slows down population growth and thus the expansion of the species.” As soon as the optimal areas are occupied, the growth of the population will slow down, according to the scientists.
The scientific investigation was based on a long-term dataset provided by the Federal Documentation and Consultation Centre on Wolves in Germany (DBBW) and included the surveys and findings of the comprehensive wolf monitoring in the German Federal States. It furthermore considered the results from tens of thousands of DNA analyses by the Senckenberg Center for Wildlife Genetics, which made this scientific investigation possible in the first place. The team also determined the reproductive performance of a total of 201 breeding females from 165 territories which were part of the analysed long-term dataset from 2000 to 2020. “We were able to analyse data from those female wolves over the years, that had offspring – at on average for 2.8 years”, says IZW scientist and first author of the paper Dr Aimara Planillo. “The analyses also show higher reproductive success of females with more experience and in more suitable habitats, with up to five reproductive years.” Summarising, the models show that a well-suited habitat and the reproduction experience of the female have a positive effect also on litter size, which in Germany averages at least four offspring.
Similar scientific analyses in other countries and regions illustrate how high the survival rate for adult wolves in Germany actually is. Other non-hunted populations also have high adult wolf survival rates of 78 per cent in the USA or 82 per cent in the Alpine regions in central Europe, although these do not come close to the 88 per cent in Germany. The reason for this is that the German population is still expanding.
The Department of Ecological Dynamics at the Leibniz-IZW investigates (among other things) the population development of large carnivores such as the wolf or Eurasian lynx using individual-based, spatial models, ranging from analysing past processes – such as the recolonisation of Germany by the wolf – to predicting future developments. For the paper recently published in “Wildlife Biology”, the scientists used demographic data on the wolf population (age, sex, year and place of birth, dates and places of resighting as well as cause of death) from the years 2000 to 2020 and related them to environmental variables such as habitat suitability (accounts for the different land use types and human disturbance effects, e.g. forested areas, distance to roads or human density), wolf population density (annual density of wolf territories around the focal territory) and the season of the year.
A significant proportion of the data comes from the ongoing molecular genetic analysis of samples collected in the field, which are sent to Senckenberg as part of the wolf monitoring programme of the German Federal States. Based on the genetic profiles created, numerous wolf individuals are collected several times over the years and can be assigned to wolf packs by analysing their relatedness. The Leibniz-IZW team then developed spatio-statistical models to determine the influence of environmental variables on the probability of survival of the population, the annual survival rates of different age classes, the probability of reproduction and reproductive performance. This revealed how well a variable – such as high habitat quality – can predict each population parameter and how substantial its influence is on the number and spatial distribution of wolves in Germany.
Previous scientific investigations by the Leibniz-IZW showed that
the recolonisation of Germany by wolves is not a homogeneous, continuous process, but characterised by changing conditions. This means, for example, that wolves show different behaviours during different phases with regard to the suitability of habitats: In early phases, wolves liked “cherry-picking” when establishing new territories, while they were much less selective during later phases when the population was close to habitat saturation. The lower survival rate of young animals identified in the current paper and the lower number of offspring in less suitable areas provide an explanation for these preferences of wolves. Additional information: https://www.izw-berlin.de/en/press-release/wolves-like-cherry-picking-modelling-shows-how-they-recolonised-germany-and-where-they-could-live-in-the-future.html (Leibniz-IZW press release from November 16, 2023)
the wolf population in Germany is essentially healthy and that human-caused deaths such as traffic accidents and illegal killings are responsible for the overwhelming majority of wolves found dead. Data from the 1,000 wolves dissected at the Leibniz-IZW in Germany show that around three quarters of dead wolves die in traffic collisions – mostly with cars on country roads or motorways. In 13.5 per cent of all wolves examined, evidence of a criminal offence such as illegal gun wounds was found, although the animals did not always die as a result. Additional information: https://www.izw-berlin.de/en/press-release/systematic-monitoring-leibniz-izw-carries-out-1000th-wolf-autopsy-since-the-species-comeback-to-germany.html (Leibniz-IZW press release from July 23, 2024)
The scientific investigation was funded by the Federal Agency for Nature Conservation (BfN) with funds from the Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection (BMUV) under grant number 3521 83 1300.
Habitat and density effects on the demography of an expanding wolf population in Central Europe
Article Publication Date
28-Oct-2024
Temperature at Roque de los Muchachos Observatory rose 1.1 ºC in 20 years, twice as much as predicted by climate models
Universitat Autonoma de Barcelona
The meteorological data recorded over the past two decades by sensors of the Roque de los Muchachos astronomical observatory facilities point to a rise of 1.1 ºC in the average temperature. The analysis, led by UAB researchers, shows more than double the increase predicted by climate models for the same area, and even more than expected for the next 20 years. Researchers from the Department of Physics of the Universitat Autònoma de Barcelona led a long-term study of climatic conditions at one of the main astronomical observation sites in the northern hemisphere: the Roque de los Muchachos Observatory, on the island of La Palma. In an area located 200 metres below the ridge on which most of the optical telescopes such as the Gran Telescopio Canarias are located, are the MAGIC Telescopes, built to detect very high energy gamma-ray sources by a collaboration in which UAB researchers were also involved. It is also the site of the construction of the northern hemisphere’s Cherenkov Telescope Array Observatory (CTAO). UAB researchers Markus Gaug and Lluís Font analysed a unique series of meteorological data from the area recorded over a period of 20 years by the meteorological instruments installed on the roof of the MAGIC telescope control building. The weather station has sent data on temperature, relative humidity, atmospheric pressure and wind speed and direction every two seconds during all this time. “The station was built with the intention to have some guidance for telescope operations, not to characterise local weather professionally, let alone the effects of climate change on the measured parameters,” explains Markus Gaug. But “the fact that they were relatively low-cost devices has been an advantage, since they had to be changed and recalibrated every two years or so, which has favoured the reliability of the data and greatly limited the effects of long-term sensor drifts, which are difficult to detect,” he adds. The Spanish meteorological service, AEMET, did not install a professional station at Roque de los Muchachos until 2022. However, thanks to data from 36 other AEMET weather stations spread across the island of Tenerife, it has been possible to carry out studies of temperature variation in the Canary Islands for many years. Some studies show an increase of 0.3 ºC per decade between 1970 and 2010. Other more recent studies had obtained an increase per decade of up to 0.25 ºC in the same area with historical data up to 2014, and the models predicted between 2015 and 2050 a temperature increase of 0.3 to 0.5 ºC per decade. Based on data recorded since 2004 by the MAGIC telescopes, and using advanced statistical analysis, researchers from the UAB Department of Physics were able to very accurately determine the climate trends in this area. The experimental data obtained show an increase of 1.1 ºC over the past 20 years, i.e. 0.55 ºC per decade. This is more than double the increase predicted by climate models for the same area, and even more than expected for the next 20 years. The results also show an increase in the diurnal temperature range, the difference between the highest and lowest temperatures during a 24-hour period, of 0.13 ºC per decade, and also an increase in seasonal temperature oscillations of 0.29 ºC per decade. One of the most surprising data observed is the increase in average daily relative humidity of 4% per decade. This is an increase that was also observed in other studies at the Mauna Kea observatory on the island of Hawaii, and contrary to the decrease in humidity recorded at the other continental observatories. The researchers consider that a possible explanation for this difference between the island and continental observatories is the increase in seawater evaporation as a result of global warming. Scientists monitored the variations in the climate at these sites after the scientific community expressed concerns about the impact of climate change on the viability and quality of data collected by unique observatories in the world, such as those at Roque de los Muchachos. In particular, the atmosphere of the subtropical zone of the Canary Islands is highly valued for astronomical observation as it is very stable throughout the year. The MAGIC telescopes are located above a thermal inversion layer with low pressures and excellent observing conditions with very dry and clean air. Fortunately for the astronomers, the UAB study found no significant changes in the frequency of rainfall or, above all, in the occurrence of strong storms. In this sense, one of the data analysed by the researchers was the rate at which temperature may change, which has remained below variations of half a degree per minute in all measurements, a condition that meets the requirements for the proper functioning of the future Cherenkov Telescope Array Observatory (CTAO). “At the moment, while using linear models, there is no evidence that the changes detected in the meteorological conditions could affect the operation of the telescopes or increase the time they will have to remain inactive due to inclement weather in the coming years, but these results are further evidence of the worrying pace of global warming”, says Lluís Font. “In addition, we all know that after a certain temperature increase, the linearity of the climate system ends and that can lead us to the 'tipping points' where the climate changes its behaviour drastically”, adds Markus Gaug. The research was published in the journal Monthly Notices of the Royal Astronomical Society. Led by researchers in the UAB Department of Physics Markus Gaug and Lluís Font, also attached to the Centre for Space Studies and Research (CERES-IEEC) of the UAB, the study included the collaboration of IFAE scientists and several universities in Italy and Germany. The work is also co-authored by Sofia Almirante Castillo, who participated in the research with a final degree project in 2022, when she was a student at the UAB, under the direction of Markus Gaug.
The future of chimpanzees depends on smart conservation strategies and that requires data, lots of data. Ecologist Adrienne Chitayat conducted research on chimpanzees in Tanzania and is the first to systematically survey the population density in the entirety of Mahale Mountains National Park. In her dissertation, she provides a detailed baseline of the density of chimpanzees in the park, which is part of the Greater Mahale Ecosystem. Chitayat also developed a new, deep learning-based acoustic detector that can identify chimpanzee sounds. This technology allows chimpanzee populations to be monitored more efficiently and human-related threats to be more easily anticipated. Chitayat will defend her PhD on Thursday, 7 November, at the University of Amsterdam.
Chimpanzees are, along with bonobos, our closest living relatives. The largest population of chimpanzees in Tanzania, the most southern and eastern extent of this species’ range, lives in the Greater Mahale Ecosystem, which covers almost 20,000 km2. It includes the Mahale Mountains National Park, a crucial habitat for the eastern chimpanzee (Pan troglodytes schweinfurthii). ‘Despite the importance of the area – it has one of longest running research sites for chimpanzees – there has been very little research on the chimpanzees across the entire park,’ says Chitayat. ‘There have been estimates based on small-scale or localized surveys, but no comprehensive baseline data. And without that data, it is difficult to understand chimpanzee population patterns and develop good conservation strategies. My goal was to fill that gap.’
Counting nests Chimpanzees sleep in nests and rarely use the same nest two nights in a row, meaning they make a new one every day. By counting the nests and determining how old they were, Chitayat was able to make a reliable estimate of the chimpanzee density for sites across the entire park. She found that the density varies from 1.1 to 3.7 chimpanzees per square kilometer.
In the frontlines of climate change The National Park is exceptionally diverse, with landscapes ranging from dense rainforests to vast savannahs. Chitayat: ‘What is striking is that the chimpanzees use the entire habitat, and not just the forested areas. We found them in both open and closed vegetation, with population density related to ecological factors such as available food sources. In open, drier areas with forests mostly in strips, there is less food and chimpanzee density is lower.
‘By looking at how the chimpanzees use the landscape and move within it, we can conclude that not only the densely forested areas are important for the protection of the animals. This ecosystem is on the frontline of climate change. That is where one of the greatest threats lies. By taking care of, for example, corridors that connect important or isolated areas, we support the ability of chimpanzees to move more freely and better protect the longevity of the population.’
Learning from sounds Counting nests, as Chitayat has now done for the entire National Park, is a good and reliable method of monitoring chimpanzees. But it is also time-consuming and expensive. Moreover, chimpanzees are difficult to habituate (get them used to people) for up close observations. According to Chitayat, we therefore need other ways to study those that are unhabituated, which encompasses the majority of chimpanzees.
She developed a new acoustic detector based on deep learning to be used with passive acoustic monitoring. Chitayat: ‘Passive acoustic monitoring is a revolutionary technique that automatically records all the sounds in the vicinity of the acoustic device, including the sounds of chimpanzees. It can be used to find out where the chimpanzees are, how often, at what times, and how many individuals. The problem is that you have hours, days, even weeks of sound recordings that are far too laborious to listen to manually.’ Chitayat therefore investigated whether she could automate the identification of chimpanzee sounds to more efficiently sort through the vast datasets using deep learning.
From loud pant-hoots to soft grunts To get the deep learning algorithm to work properly, it had to be fed with a lot of training data (examples of chimpanzee sounds and their environment). Chitayat: ‘That was difficult, because there are no large databases of sounds available – unlike with birds, for example. Chimpanzees make a lot of different sounds to communicate with each other, from loud pant-hoots used to impress and communicate over long distances to soft grunts used as a greeting to each other. We focused on pant-hoots, which made our task extra difficult because of the complexity and variability of these calls’.
Chitayat managed to make the acoustic detector a viable method. ‘This is a big step, but not the last. Machine learning technology could eventually be used to distinguish individual chimpanzees. That would allow you to learn more about the demography within groups – such as the number of males and females and their age class – and their patterns and habits. The more we learn, the better we can protect chimpanzees.’
Defence details Adrienne Chitayat: Chimpanzee Pan troglodytes schweinfurthii Conservation in the Greater Mahale Ecosystem, Western Tanzania: Establishing a Baseline and Enhancing Future Monitoring Efforts through Technology. Supervisor is Prof. S.A. Wich. Co-supervisor is Dr A.K. Piel.
Time and location Chitayat’s defence will be held on Thursday, 7 November, at 16.00, in the Agnietenkapel.
Adrienne Chitayat in the Mahale Mountains National Par
Chimpanzees in the Mahale Mountains National Park
Chimpanzee in the Mahale Mountains National Park
The Mahale Mountains National Park
Credit
Adrienne Chitayat
SPACE/COSMOS
New ESO image captures a dark wolf in the sky
ESO
image:
Fittingly nicknamed the Dark Wolf Nebula, this cosmic cloud was captured in a 283-million-pixel image by the VLT Survey Telescope (VST) at ESO’s Paranal Observatory in Chile. Located around 5300 light-years from Earth, the cold clouds of cosmic dust create the illusion of a wolf-like silhouette against a colourful backdrop of glowing gas clouds.
For Halloween, the European Southern Observatory (ESO) reveals this spooktacular image of a dark nebula that creates the illusion of a wolf-like silhouette against a colourful cosmic backdrop. Fittingly nicknamed the Dark Wolf Nebula, it was captured in a 283-million-pixel image by the VLT Survey Telescope (VST) at ESO’s Paranal Observatory in Chile.
Found in the constellation Scorpius, near the centre of the Milky Way on the sky, the Dark Wolf Nebula is located around 5300 light-years from Earth. This image takes up an area in the sky equivalent to four full Moons, but is actually part of an even larger nebula called Gum 55. If you look closely, the wolf could even be a werewolf, its hands ready to grab unsuspecting bystanders…
If you thought that darkness equals emptiness, think again. Dark nebulae are cold clouds of cosmic dust, so dense that they obscure the light of stars and other objects behind them. As their name suggests, they do not emit visible light, unlike other nebulae. Dust grains within them absorb visible light and only let through radiation at longer wavelengths, like infrared light. Astronomers study these clouds of frozen dust because they often contain new stars in the making.
Of course, tracing the wolf’s ghost-like presence in the sky is only possible because it contrasts with a bright background. This image shows in spectacular detail how the dark wolf stands out against the glowing star-forming clouds behind it. The colourful clouds are built up mostly of hydrogen gas and glow in reddish tones excited by the intense UV radiation from the newborn stars within them.
Some dark nebulae, like the Coalsack Nebula, can be seen with the naked eye –– and play a key role in how First Nations interpret the sky[1] –– but not the Dark Wolf. This image was created using data from the VLT Survey Telescope, which is owned by the National Institute for Astrophysics in Italy (INAF) and is hosted at ESO’s Paranal Observatory, in Chile’s Atacama Desert. The telescope is equipped with a specially designed camera to map the southern sky in visible light.
The picture was compiled from images taken at different times, each one with a filter letting in a different colour of light. They were all captured during the VST Photometric Hα Survey of the Southern Galactic Plane and Bulge (VPHAS+), which has studied some 500 million objects in our Milky Way. Surveys like this help scientists to better understand the life cycle of stars within our home galaxy, and the obtained data are made publicly available through the ESO science portal. Explore this treasure trove of data yourself: who knows what other eerie shapes you will uncover in the dark?
Notes
[1] The Mapuche people of south-central Chile refer to the Coalsack Nebula as ‘pozoko’ (water well), and the Incas called it ‘yutu’ (a partridge-like bird).
More information
The European Southern Observatory (ESO) enables scientists worldwide to discover the secrets of the Universe for the benefit of all. We design, build and operate world-class observatories on the ground — which astronomers use to tackle exciting questions and spread the fascination of astronomy — and promote international collaboration for astronomy. Established as an intergovernmental organisation in 1962, today ESO is supported by 16 Member States (Austria, Belgium, Czechia, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom), along with the host state of Chile and with Australia as a Strategic Partner. ESO’s headquarters and its visitor centre and planetarium, the ESO Supernova, are located close to Munich in Germany, while the Chilean Atacama Desert, a marvellous place with unique conditions to observe the sky, hosts our telescopes. ESO operates three observing sites: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its Very Large Telescope Interferometer, as well as survey telescopes such as VISTA. Also at Paranal ESO will host and operate the Cherenkov Telescope Array South, the world’s largest and most sensitive gamma-ray observatory. Together with international partners, ESO operates ALMA on Chajnantor, a facility that observes the skies in the millimetre and submillimetre range. At Cerro Armazones, near Paranal, we are building “the world’s biggest eye on the sky” — ESO’s Extremely Large Telescope. From our offices in Santiago, Chile we support our operations in the country and engage with Chilean partners and society.
With new imaging capabilities, the first successful dark-matter detector might be some old rock
Virginia Tech
image:
Ph.D. candidate Keegan Walkup (at left) and physicist Patrick Huber work in the new lab that Huber is establishing to look for evidence of dark matter inside the crystal lattice structures of old rocks.
Credit: Photo by Spencer Coppage for Virginia Tech.
The visible universe — all the potatoes, gas giants, steamy romance novels, black holes, questionable tattoos, and overwritten sentences — accounts for only 5 percent of the cosmos.
A Virginia Tech-led team is hunting for the rest of it, not with telescopes or particle colliders, but by scrutinizing billion-year-old rocks for traces of dark matter.
In leading a transdisciplinary team from multiple universities on this unconventional search, physics’ Patrick Huber is also taking an unconventional step: from theoretical work into experimental work.
With support from a $3.5 million Growing Convergence Research award from the National Science Foundation and a separate $750,000 award from the National Nuclear Security Administration, Huber is building a new lab in Robeson Hall to test dark matter theories — and see what else might come to light along the way.
Dark matter is super dark
Scientists can only infer dark matter’s existence because objects in the universe fall faster than they should around the center of galaxies. Gravity from this unseen substance accounts for the extra oomph.
Unlike the bump and grind of regular stuff, dark matter is thought to interact only very weakly with other matter, imperceptible except when one happens to bump into a nucleus of a visible matter atom. Recoiling from the collision like an atomic billiard ball, the nucleus deposits a spark of energy.
Over the past 50 years, physicists have conducted all manner of dark-matter experiments in hopes of witnessing one of these rare recoil events.
So far? Dark matter has stayed dark. Physicists haven’t turned up any hard evidence for dark matter. Now they’re turning down — deep down.
Paleodetectives
If dark matter exists, there’s a chance it has interacted with the Earth at some point in its 4.6 billion-year-old history. What if, instead of waiting for dark matter to come to them, scientists could excavate ancient evidence from minerals deep in the Earth?
While the idea for using rocks as subterranean detectors was first proposed in the 1980s, technological advances prompted researchers, including Huber, to revisit this idea.
“It’s crazy. When I first heard about this idea, I was like — this is insane. I want to do it,” said Huber, the William E. Hassinger, Jr. Senior Faculty Fellow.
Huber, being a theoretical physicist, came up with a theory of how to solve it. But the theory wasn’t enough. If this plan was possible, he wanted to see what it would take to execute it.
“Other people in their midlife crisis might take a mistress or get a sports car. I got a lab,” Huber said.
Who knocked the nuclei?
By developing and using sophisticated imaging techniques, Huber and his collaborators hope to uncover miniature trails of destruction left by long-ago dark matter interactions inside crystal lattice structures.
When a high-energy particle bounces off a nucleus inside a rock, the explosive recoil can pop a nucleus out of place, said Vsevolod Ivanov, a researcher at the Virginia Tech National Security Institute who is collaborating with Huber. The ejected nucleus and the empty gap it leaves behind represent structural changes within crystal.
“We’ll take a crystal that’s been exposed to different particles for millions of years and subtract the distributions that correspond to things we do know,” Ivanov said. “Whatever is left must be something new, and that could be the dark matter.”
Most dark matter experiments are conducted underground to cut back on interference from other high-energy particles called cosmic rays, but going underground presents a new set of problems. The planet pulses with a radioactive background that can also jostle nuclei. University Distinguished Professor Robert Bodnar, recently inducted into the National Academy of Sciences, will be working with Huber’s team to identify, locate, and characterize minerals that could serve as suitable detectors.
Proof in 3D
To start in on this massive imaging task, Huber is working with researchers at the University of Zurich’s Brain Research Institute who provided access to special microbiology imaging technology typically used to image animal nervous systems.
The team has already started generating 3D renderings of high-energy particle tracks in synthetic lithium fluoride. This artificial crystal won’t make a good dark-matter detector, said Huber, but it will help establish the full range of signals while keeping the crystal intact. In an unexpected twist, applications of lithium fluoride imaging technology include “nuclear transparency devices,” which might look like backpack-sized monitoring devices for nuclear reactors.
With tangential outputs from this “insane” research objective already proving of immediate value, Huber his collaborators will dig deeper and look closer to see if an old rock can tell us how the stars fly around the galaxy.
NASA’s Hubble, Webb probe surprisingly smooth disk around Vega
NASA/Goddard Space Flight Center
image:
[left] A Hubble Space Telescope false-color view of a 100-billion-mile-wide disk of dust around the summer star Vega. Hubble detects reflected light from dust that is the size of smoke particles largely in a halo on the periphery of the disk. The disk is very smooth, with no evidence of embedded large planets. The black spot at the center blocks out the bright glow of the hot young star. [right] The James Webb Space Telescope resolves the glow of warm dust in a disk halo, at 23 billion miles out. The outer disk (analogous to the solar system’s Kuiper Belt) extends from 7 billion miles to 15 billion miles. The inner disk extends from the inner edge of the outer disk down to close proximity to the star. There is a notable dip in surface brightness of the inner disk from approximately 3.7 to 7.2 billion miles. The black spot at the center is due to lack of data from saturation.
Credit: NASA, ESA, CSA, STScI, S. Wolff (University of Arizona), K. Su (University of Arizona), A. Gáspár (University of Arizona)
In the 1997 movie "Contact," adapted from Carl Sagan's 1985 novel, the lead character scientist Ellie Arroway (played by actor Jodi Foster) takes a space-alien-built wormhole ride to the star Vega. She emerges inside a snowstorm of debris encircling the star — but no obvious planets are visible.
It looks like the filmmakers got it right.
A team of astronomers at the University of Arizona, Tucson used NASA's Hubble and James Webb space telescopes for an unprecedented in-depth look at the nearly 100-billion-mile-diameter debris disk encircling Vega. "Between the Hubble and Webb telescopes, you get this very clear view of Vega. It's a mysterious system because it's unlike other circumstellar disks we've looked at," said Andras Gáspár of the University of Arizona, a member of the research team. "The Vega disk is smooth, ridiculously smooth."
The big surprise to the research team is that there is no obvious evidence for one or more large planets plowing through the face-on disk like snow tractors. "It's making us rethink the range and variety among exoplanet systems," said Kate Su of the University of Arizona, lead author of the paper presenting the Webb findings.
Webb sees the infrared glow from a disk of particles the size of sand swirling around the sizzling blue-white star that is 40 times brighter than our Sun. Hubble captures an outer halo of this disk, with particles no bigger than the consistency of smoke that are reflecting starlight.
The distribution of dust in the Vega debris disk is layered because the pressure of starlight pushes out the smaller grains faster than larger grains. "Different types of physics will locate different-sized particles at different locations," said Schuyler Wolff of the University of Arizona team, lead author of the paper presenting the Hubble findings. "The fact that we're seeing dust particle sizes sorted out can help us understand the underlying dynamics in circumstellar disks."
The Vega disk does have a subtle gap, around 60 AU (astronomical units) from the star (twice the distance of Neptune from the Sun), but otherwise is very smooth all the way in until it is lost in the glare of the star. This shows that there are no planets down at least to Neptune-mass circulating in large orbits, as in our solar system, say the researchers.
"We're seeing in detail how much variety there is among circumstellar disks, and how that variety is tied into the underlying planetary systems. We’re finding a lot out about the planetary systems — even when we can’t see what might be hidden planets," added Su. "There's still a lot of unknowns in the planet-formation process, and I think these new observations of Vega are going to help constrain models of planet formation."
Disk Diversity
Newly forming stars accrete material from a disk of dust and gas that is the flattened remnant of the cloud from which they are forming. In the mid-1990s Hubble found disks around many newly forming stars. The disks are likely sites of planet formation, migration, and sometimes destruction. Fully matured stars like Vega have dusty disks enriched by ongoing "bumper car" collisions among orbiting asteroids and debris from evaporating comets. These are primordial bodies that can survive up to the present 450-million-year age of Vega (our Sun is approximately ten times older than Vega). Dust within our solar system (seen as the Zodiacal light) is also replenished by minor bodies ejecting dust at a rate of about 10 tons per second. This dust is shoved around by planets. This provides a strategy for detecting planets around other stars without seeing them directly – just by witnessing the effects they have on the dust.
"Vega continues to be unusual," said Wolff. "The architecture of the Vega system is markedly different from our own solar system where giant planets like Jupiter and Saturn are keeping the dust from spreading the way it does with Vega."
For comparison, there is a nearby star, Fomalhaut, which is about the same distance, age and temperature as Vega. But Fomalhaut's circumstellar architecture is greatly different from Vega's. Fomalhaut has three nested debris belts.
Planets are suggested as shepherding bodies around Fomalhaut that gravitationally constrict the dust into rings, though no planets have been positively identified yet. "Given the physical similarity between the stars of Vega and Fomalhaut, why does Fomalhaut seem to have been able to form planets and Vega didn't?" said team member George Rieke of the University of Arizona, a member of the research team. "What's the difference? Did the circumstellar environment, or the star itself, create that difference? What's puzzling is that the same physics is at work in both," added Wolff.
First Clue to Possible Planetary Construction Yards
Located in the summer constellation Lyra, Vega is one of the brightest stars in the northern sky. Vega is legendary because it offered the first evidence for material orbiting a star — presumably the stuff for making planets — as potential abodes of life. This was first hypothesized by Immanuel Kant in 1775. But it took over 200 years before the first observational evidence was collected in 1984. A puzzling excess of infrared light from warm dust was detected by NASA's IRAS (Infrared Astronomy Satellite). It was interpreted as a shell or disk of dust extending twice the orbital radius of Pluto from the star.
In 2005, NASA's infrared Spitzer Space Telescope mapped out a ring of dust around Vega. This was further confirmed by observations using submillimeter telescopes including Caltech's Submillimeter Observatory on Mauna Kea, Hawaii, and also the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, and ESA's (European Space Agency's) Herschel Space Telescope, but none of these telescopes could see much detail. "The Hubble and Webb observations together provide so much more detail that they are telling us something completely new about the Vega system that nobody knew before," said Rieke.
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).
The Hubble Space Telescope has been operating for over three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, Colorado, also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, Maryland, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.
Ray Villard, Christine Pulliam Space Telescope Science Institute, Baltimore, MD
Journal
The Astrophysical Journal
Method of Research
Observational study
Subject of Research
Not applicable
Article Title
Deep Search for a scattered light dust halo around Vega with the Hubble Space Telescope, and Imaging of the Vega Debris System using JWST/MIRI
Mission to International Space Station launches research on brain organoids, heart muscle atrophy, and cold welding
The SpaceX CRS-31 mission to the ISS for NASA includes studies on in-space manufacturing, cardiac health, and a method to repair spacecraft damaged by debris
International Space Station U.S. National Laboratory
image:
The SpaceX Dragon spacecraft atop the Falcon 9 rocket at Kennedy Space Center in March 2023.
KENNEDY SPACE CENTER (FL), November 1, 2024 – More than 25 payloads sponsored by the International Space Station (ISSInternational Space Station) National Laboratory, including technology demonstrations, in-space manufacturing, student experiments, and multiple projects funded by the U.S. National Science Foundation (NSF), are bound for the orbiting outpost. These investigations, launching on SpaceX’s 31st Commercial Resupply Services (CRS) mission for NASANational Aeronautics and Space Administration, aim to improve life on Earth through space-based research and foster a sustainable economy in low Earth orbit(Abbreviation: LEO) The orbit around the Earth that extends up to an altitude of 2,000 km (1,200 miles) from Earth’s surface. The International Space Station’s orbit is in LEO, at an altitude of approximately 250 miles. (LEO).
The mission is scheduled to launch no earlier than Monday, November 4 at 9:29 p.m. EST from Launch Complex 39A at NASA’s Kennedy Space Center. Below highlights some of the ISS National Lab-sponsored projects on this mission.
Bristol Myers Squibb (BMS) will build on its legacy of protein crystallization on the space station with a project, in collaboration with ISS National Lab Commercial Service ProviderImplementation Partners that own and operate commercial facilities for the support of research on the ISS or are developing future facilities. Redwire Space, seeking to crystallize model small molecule compounds to support the manufacturing of more effective therapeutics. Crystals grown in microgravityThe condition of perceived weightlessness created when an object is in free fall, for example when an object is in orbital motion. Microgravity alters many observable phenomena within the physical and life sciences, allowing scientists to study things in ways not possible on Earth. The International Space Station provides access to a persistent microgravity environment. are often larger and more well-ordered than those grown on the ground and could have improved morphology (geometric shape).
NSF is funding four investigations launching on this mission, including a collaborative project from Oregon State University and Texas Tech University focused on cardiac health. This experiment will use 3D-bioprinted cardiac organoids to study microgravity-induced heart muscle atrophy. Results could lead to an increased understanding of heart muscle atrophy, which occurs in several conditions, such as cancer, muscle disease, muscular dystrophy, diabetes, sepsis, and heart failure.
Multiple projects sponsored by the ISS National Lab and funded by NASA focus on in-space manufacturing. One investigation by Sachi Bioworks, working with ISS National Lab Commercial Service Provider Space Tango, could help advance the development of new therapeutics for neurodegenerative conditions. The project will use brain organoids in microgravity to test the effects of a novel drug on Alzheimer’s disease, Parkinson’s disease, and dementia.
The Malta College of Arts, Science, and Technology is launching a project, with support from ISS National Lab Commercial Service Provider Voyager Space, to test a heatless method of welding. Cold welding is a process that bonds similar metallic materials using force or pressure instead of heat. This method could one day be used to safely repair space platforms and ensure their long-term viability, which would help to address the growing concern of space debris. In this project, the research team will test remote-operated, cold welding to apply metal patches to simulated spacecraft hull samples.
The Student Spaceflight Experiment Program (SSEP) will send 39 student-led experiments on its 18th mission to the space station. SSEP aims to prepare the next generation of scientists and engineers by actively involving school communities in the development of scientific investigations to be conducted in microgravity. More than 35 communities took part in this SSEP mission, engaging hundreds of students in grades 5-12, junior college, and undergraduate studies.
For additional information on ISS National Lab-sponsored investigations launching on NASA’s SpaceX CRS-31, visit our launch page. To learn more about the research and technology development sponsored by the ISS National Lab, including how to propose concepts for future space-based research, visit our website.
Faster space communication with record-sensitive receiver
Chalmers University of Technology
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In the new communication system from researchers at Chalmers University of Technology, in Sweden, a weak optical signal (red) from the spacecraft's transmitter can be amplified noise-free when it encounters two so-called pump waves (blue and green) of different frequencies in a receiver on Earth. Thanks to the researchers' noise-free amplifiers in the receiver, the signal is kept undisturbed and the reception on Earth becomes record-sensitive, which in turn paves the way for a more error-free and faster data transmission in space in the future.
Credit: Chalmers University of Technology | Rasmus Larsson
In space exploration, long-distance optical links can now be used to transmit images, films and data from space probes to Earth using light. But in order for the signals to reach all the way and not be disturbed along the way, hypersensitive receivers and noise-free amplifiers are required. Now, researchers at Chalmers University of Technology, in Sweden, have created a system that, with a silent amplifier and record-sensitive receiver, paves the way for faster and improved space communication.
Space communication systems are increasingly based on optical laser beams rather than radio waves, as the signal loss has been shown to be less when light is used to carry information over very long distances. But even information carried by light loses its power during the journey, and optical systems for space communication therefore require extremely sensitive receivers capable of sensing signals that have been greatly weakened before they finally reach Earth. The Chalmers researchers' concept for optical space communication opens up new communication opportunities – and discoveries – in space.
"We can demonstrate a new system for optical communication with a receiver that is more sensitive than has been demonstrated previously at high data rates. This means that you can get a faster and more error-free transfer of information over very long distances, for example when you want to send high-resolution images or videos from the Moon or Mars to Earth," says Peter Andrekson, Professor of Photonics at Chalmers and one of the lead authors of the study, which was recently published in the scientific journal Optica.
Silent amplifier with simplified transmitter improves communication
The researchers' communication system uses an optical amplifier in the receiver that amplifies the signal with the least possible noise so that its information can be recycled. Just like the glow of a flashlight, the light from the transmitter widens and weakens with distance. Without amplification, the signal is so weak after the space flight that it is drowned out by the electronic noise of the receiver. After twenty years of struggling with disturbing noise that impaired the signals, the research team at Chalmers was able to demonstrate a noise-free optical amplifier a few years ago. But until now, the silent amplifier has not been able to be used practically in optical communication links, as it has placed completely new, significantly more complex, demands on both transmitter and receiver.
Due to the limited resources and minimal space on board a space probe, it is important that the transmitter is as simple as possible. By allowing the receiver on Earth to generate two of the three light frequencies needed for noise-free amplification, and at the same time allowing the transmitter to generate only one frequency, the Chalmers researchers were able to implement the noise-free amplifier in an optical communication system for the first time. The results show an outstanding sensitivity, while complexity at the transmitter is modest.
"This phase-sensitive optical amplifier does not, in principle, generate any extra noise, which contributes to a more sensitive receiver and that error-free data transmission is achieved even when the power of the signal is lower. By generating two extra waves of different frequencies in the receiver, rather than as previously done in the transmitter, a conventional laser transmitter with one wave can now be used to implement the amplifier. Our simplification of the transmitter means that already existing optical transmitters on board satellites and probes could be used together with the noise-free amplifier in a receiver on Earth," says Rasmus Larsson, Postdoctoral Researcher in Photonics at Chalmers and one of the lead authors of the study.
Can solve problematic bottleneck
The progress means that the researchers' silent amplifiers can eventually be used in practice in communication links between space and Earth. The system is thus poised to contribute in solving a well-known bottleneck problem among space agencies today.
NASA talks about 'the science return bottleneck', and here the speed of the collection of scientific data from space to Earth is a factor that constitutes an obstacle in the chain. We believe that our system is an important step forward towards a practical solution that can resolve this bottleneck," says Peter Andrekson.
The next step for the researchers is to test the optical communication system with the implemented amplifier during field studies on Earth, and later also in communication links between a satellite and Earth.
The development of the technology has been done at Chalmers University of Technology and the research has been funded by the Swedish Research Council.
For more information, please contact:
Rasmus Larsson, Postdoctoral Researcher, Division of Photonics, Department of Microtechnology and Nanoscience, Chalmers University of Technology rasmus.larsson@chalmers.se
Peter Andrekson, Professor, Division of Photonics, Department of Microtechnology and Nanoscience, Chalmers University of Technology peter.andrekson@chalmers.se, +46 31 772 16 06
The contact persons both speak English and Swedish. They are available for live and pre-recorded interviews. At Chalmers, we have podcast studios and broadcast filming equipment on site and would be able to assist a request for a television, radio or podcast interview.
Illustration caption: In the new communication system from researchers at Chalmers University of Technology, in Sweden, a weak optical signal (red) from the spacecraft's transmitter can be amplified noise-free when it encounters two so-called pump waves (blue and green) of different frequencies in a receiver on Earth. Thanks to the researchers' noise-free amplifiers in the receiver, the signal is kept undisturbed and the reception on Earth becomes record-sensitive, which in turn paves the way for a more error-free and faster data transmission in space in the future.
Illustration credit: Chalmers University of Technology | Rasmus Larsson
Ultralow-noise preamplified optical receiver using conventional single-wavelength transmission
The dynamic core of black holes
A new study investigates the internal dynamics of black holes and their implications for future astrophysical observations
Scuola Internazionale Superiore di Studi Avanzati
Black holes continue to captivate scientists: they are purely gravitational objects, remarkably simple, yet capable of hiding mysteries that challenge our understanding of natural laws. Most observations thus far have focused on their external characteristics and surrounding environment, leaving their internal nature largely unexplored. A new study, conducted through a collaboration between the University of Southern Denmark, Charles University in Prague, Scuola Internazionale Superiore di Studi Avanzati (SISSA) in Trieste, and Victoria University of Wellington in New Zealand, and published in Physical Review Letters, examines a common aspect of the innermost region of various spacetime models describing black holes, suggesting that our understanding of these enigmatic objects may require further investigation.
According to the corresponding author, postdoc Raúl Carballo-Rubio from the research center CP3-Origins at the University of Southern Denmark, the key insight from this study is that “the internal dynamics of black holes, which remain largely uncharted, could radically transform our understanding of these objects, even from an external perspective.”
The Kerr solution to the equations of General Relativity is the most accurate representation of rotating black holes observed in gravitational astrophysics. It depicts a black hole as a maelstrom in spacetime, characterized by two horizons: an outer one, beyond which nothing can escape its gravitational pull, and an inner one that encloses a ring singularity, a region where spacetime as we know it ceases to exist. This model aligns well with observations, as deviations from Einstein's theory outside the black hole are regulated by new physics parameters, which govern the core's size and are expected to be quite small.
However, a recent study conducted by the international team mentioned above has highlighted a critical issue concerning the interior of these objects: while it was known that a static inner horizon is characterised by an infinite accumulation of energy, the study demonstrates that even more realistic dynamic black holes are subject to significant instability over relatively short timescales. This instability is due to an accumulation of energy that grows exponentially over time until it reaches a finite, but extremely large, value, capable of significantly influencing the overall geometry of the black hole and thus altering it.
The ultimate outcome of this dynamic process is still unclear, but the study implies that a black hole cannot stabilise in Kerr geometry, at least over long timescales, although the speed and magnitude of deviations from Kerr spacetime remain under investigation. As Stefano Liberati, professor at SISSA and one of the study's authors, explains: “This result suggests that the Kerr solution—contrary to previous assumptions—cannot accurately describe observed black holes, at least on the typical timescales of their existence.”
Understanding the role of this instability is therefore essential for refining theoretical models of the interior of black holes and their relationship to the overall structure of these objects. In this sense, it could provide a missing link between theoretical models and potential observations of physics beyond General Relativity. Ultimately, these results open new perspectives for studying black holes, offering an opportunity to deepen our understanding of their internal nature and dynamic behaviour.
