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In 2019, the Event Horizon Telescope (EHT) collaboration produced the first-ever image of a black hole, stunning the world.

Now, scientists are taking it further. The next generation Event Horizon Telescope (ngEHT) collaboration aims to create high-quality videos of black holes.

But this next-generation collaboration is groundbreaking in other ways, too. It’s the first large physics collaboration bringing together perspectives from natural sciences, social sciences and the humanities.

For a virtual telescope spanning the planet, the larger a telescope, the better it is at seeing things that look tiny from far away. To produce black hole images, we need a telescope almost the size of Earth itself. That’s why the EHT uses many telescopes and telescope arrays scattered across the globe to form a single, virtual Earth-sized telescope. This is known as very long baseline interferometry.

Harvard astrophysicist Shep Doeleman, the founding director of the EHT, has likened this kind of astronomy to using a broken mirror. Imagine shattering a mirror and scattering the pieces across the world. Then you record the light caught by each of these pieces while keeping track of the timing, and collect those data in a supercomputer to virtually reconstruct an Earth-sized detector.

The 2019 first-ever image of a black hole was made by borrowing existing telescopes at six sites. Now, new telescopes at new sites are being built to better fill in the gaps of the broken mirror. The collaboration is currently in the process of selecting optimal places across the world, to increase the number of sites to approximately 20.

This ambitious endeavour needs over 300 experts organised into three technical working groups and eight science working groups. The history, philosophy and culture working group has just published a landmark report outlining how humanities and social science scholars can work with astrophysicists and engineers from the first stages of a project.

The report has four focus areas: collaborative knowledge formation, philosophical foundations, algorithms and visualisation, and responsible telescope siting.

How can we all collaborate? If you’ve ever tried to write a paper (or anything!) with someone else, you know how difficult it can be. Now imagine trying to write a scientific paper with over 300 people.

Should one expect each author to believe and be willing to defend every part of the paper and its conclusions? How should we all determine what will be included? If everyone has to agree with what is included, will this result in only publishing conservative, watered-down results? And how do you allow for individual creativity and boundary-pushing science (especially when you are attempting to be the first to capture something)? To resolve such questions, it’s important to balance collaborative approaches and structure everyone’s involvement in a way that promotes consensus, but also allows people to express dissent. Diversity of beliefs and practices among collaboration members can be beneficial to science.

How do we visualise the data? The aesthetic choices regarding the final black hole images and videos take place in a broader context of visual culture.

In reality, blue flames are hotter than flames appearing orange or yellow. But in the above false-colour image of Sagittarius A* – the black hole at the centre of the Milky Way – the colour palette of orange-red hues was chosen as it was believed orange would communicate to wider audiences just how hot the glowing material around the black hole is.

This approach connects to historical practices of technology-assisted scientific images, such as those by Galileo, Robert Hooke, and Johannes Hevelius. These scientists combined their early telescopic and microscopic images with artistic techniques so they would be legible to non-specialist audiences (particularly those who did not have access to the relevant instruments).

How philosophy can help Videos of black holes would be of significant interest to theoretical physicists. However, there is a bridge between formal mathematical theory and the messy world of experiment where idealised assumptions often do not hold up.

Philosophers can help to bridge this gap with considerations of epistemic risk – such as the risk of missing the truth, or making an error. Philosophy also helps to investigate the underlying assumptions physicists might have about a phenomenon.

For example, one approach to describing black holes is called the “no-hair theorem”. It’s the idea that an isolated black hole can be simplified down to just a few properties, and there’s nothing complex (hairy) about it. But the no-hair theorem applies to stable black holes. It relies on an assumption that black holes eventually settle down to a stationary state.

Responsible telescope siting The choice of locations for telescopes, or telescope siting, has historically been determined by technical and economic considerations – including weather, atmospheric clarity, accessibility and costs. There has been a historic lack of consideration for local communities, including First Nations peoples.

As the struggle at Mauna Kea in Hawai’i highlights, scientific collaborations are obligated to address ethical, social and environmental considerations when siting.

The ngEHT aims to advance responsible siting practices. It draws together experts in philosophy, history, sociology, community advocacy, science, and engineering to contribute to the decision-making process in ways that include cultural, social and environmental factors when choosing a new telescope location.

Overall, this collaboration is an exciting example of how ambitious plans demand innovative approaches – and how sciences are evolving in the 21st century.


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NASA Data Empowers Global Response to Rising Sea Levels

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NASA Data Empowers Global Response to Rising Sea Levels

Coastal communities around the world are confronting the realities of rising sea levels, which threaten both daily life and essential infrastructure. In response, NASA has collaborated with agencies such as the US Department of Defense, the World Bank, and the United Nations to deliver detailed data on global sea level rise. This information, accessible through NASA’s Earth Information Center, is intended to aid in the preparation and planning for coastal impacts expected through the year 2150.

As per a report by NASA, the centre offers projections of future sea levels and potential regional flooding over the next 30 years. The report highlights that this resource combines data from NASA’s ongoing satellite monitoring with computer modelling of ice sheet dynamics and ocean behaviour, alongside assessments from global authorities like the Intergovernmental Panel on Climate Change. These tools are designed to equip communities with accurate data on which they can base crucial coastal infrastructure and climate resilience plans.

Global Applications of NASA’s Data

Global institutions are using NASA’s sea level data to shape policies and implement adaptive strategies in vulnerable regions, the report mentioned. The World Bank, for example, integrates this information into Climate Risk Profiles for countries most susceptible to rising sea levels. Similarly, the U.S. Department of Defense leverages the data to foresee and mitigate the impacts on its coastal facilities, while the U.S. Department of State uses the information in disaster preparedness and adaptation planning for its international allies, the report further adds.

Selwin Hart, Assistant Secretary-General and special adviser to the United Nations on climate action, described the data as “a critical resource for protecting lives and livelihoods,” emphasising the disparity in impacts between a global warming limit of 1.5 degrees Celsius and current policy projections. This data, he noted, underscores the urgent need for action in vulnerable coastal areas.

Accelerating Rise of Global Sea Levels

The current rate of sea level rise has been shown to increase significantly, with nearly all coastal countries observing heightened sea levels from 1970 to 2023. According to Ben Hamlington, head of NASA’s sea level change team, the rise in sea levels is occurring at an accelerated pace, with average increases nearly doubling over the past three decades. Notably, NASA’s projections indicate that Pacific Island nations will see at least a 15-centimetre rise by 2050, accompanied by a marked increase in high-tide flooding.

The new data platform, as explained by Nadya Vinogradova Shiffer, director of NASA’s ocean physics programme, allows communities worldwide to anticipate future flooding scenarios.

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Ancient pebbles in Israel hint at the earliest form of wheel technology

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Ancient pebbles in Israel hint at the earliest form of wheel technology

Archaeologists in Israel have uncovered doughnut-shaped pebbles that may be among the earliest forms of wheel-like technology. Found at the Nahal Ein Gev II site in northern Israel, these 12,000-year-old limestone pebbles feature central holes and are thought to have been used as spindle whorls—a tool for spinning fibres like flax and wool.

Talia Yashuv, a graduate student and co-author of the study at the Hebrew University of Jerusalem’s Institute of Archaeology, told LiveScience that these ancient artefacts suggest early experimentation with rotational tools that could have laid the foundation for later advancements like the potter’s wheel and the cart wheel. This discovery was published in PLOS One on November 13, offering a glimpse into pre-agricultural technology in the region.

The roughly 100 perforated pebbles were analysed by Yashuv and Leore Grosman, a professor of prehistoric archaeology at the same institute. After scanning each pebble in 3D, the team produced detailed models to assess their potential uses. Most of the pebbles were thought unlikely to serve as fishing weights or beads due to their size and shape, which diverge from artefacts used in similar periods. Instead, the team recreated spindle whorls from the scanned models, which traditional craft expert Yonit Crystal used to spin flax and wool. While the flax was easier to handle, the replicas demonstrated that the pebbles were likely effective as spindle whorls, supporting early textile production, the study noted.

Implications of the Findings

The findings indicate that these spindle whorls could mark a key point in technological evolution, potentially linked to new methods of storage and survival. Alex Joffe, a director at the Association for the Study of the Middle East and Africa and experienced archaeologist, told LiveScience that the possibility that these artefacts could have enabled innovations like bags or fishing lines. Yorke Rowan, an archaeology professor at the University of Chicago, echoed this view, noting that the analysis represents a “critical turning point” in early technology.

A Continuing Debate

While these pebbles may represent one of the earliest uses of wheel-like forms, Carole Cheval, an expert in prehistoric textiles at CEPAM in France, told that the publication that she observed that similar objects have been found in other regions, possibly from earlier periods. This adds another layer to understanding the origins of rotational technology, highlighting the ongoing exploration of ancient human innovation.

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Binar satellites re-enter early due to high solar activity

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Binar satellites re-enter early due to high solar activity

An increase in solar activity has resulted in the early re-entry of three CubeSats from Curtin University’s Binar Space Program. These small satellites, which operated at low Earth orbit, were designed to last for at least six months. However, due to intensified solar conditions, they were destroyed within two months, significantly shortening their scientific mission.

CubeSats like Binar-2, 3 and 4 are particularly vulnerable to space weather impacts because they lack propulsion systems that could counteract the heightened atmospheric drag caused by solar activity. The satellite programme had launched Binar-1 in 2021 during relatively low solar activity, which allowed it to complete a full year in orbit.

The Science Behind Solar Activity

As per a report by The Conversation, solar activity, which includes phenomena such as solar flares, sunspots and solar wind, follows an 11-year cycle driven by the Sun’s magnetic field. Known as “solar cycle 25,” this phase has shown unexpected activity levels, currently over 1.5 times higher than projected. This has impacted not only the Binar satellites but also large-scale operations like the Starlink constellation and the International Space Station, both of which require continuous adjustments to counter increased drag.

Impact of Space Weather on Satellites and Earth

Increased solar activity generates higher levels of ionising radiation and charged particles. This can damage sensitive satellite electronics, disrupt radio communications and increase radiation exposure for astronauts. The intensified solar conditions have also expanded the Earth’s atmosphere outward, leading to increased drag for satellites in low Earth orbit. This affects many smaller satellites, which lack the capability to adjust their altitude.

The recent solar activity has also created more visible auroras, with these atmospheric light displays appearing closer to the equator than seen in decades.

Future Considerations for Space Missions

Despite current challenges, solar activity is expected to decline gradually, reaching a minimum by 2030. This pause may offer more favourable conditions for future missions. In response to current conditions, work has commenced on future Binar missions, which may benefit from a more predictable space weather environment.

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