Category: 7. Science

The ubiquitous, evolutionarily oldest RNAs and proteins exclusively use rather rare zinc as transition metal cofactor and potassium as alkali metal cofactor, which implies their abundance in the habitats of the first organisms.

Intriguingly, lunar rocks contain a hundred times less zinc and ten times less potassium than the Earth’s crust; the Moon is also depleted in other moderately volatile elements (MVEs). Current theories of impact formation of the Moon attribute this depletion to the MVEs still being in a gaseous state when the hot post-impact disk contracted and separated from the nascent Moon.

The MVEs then fell out onto juvenile Earth’s protocrust; zinc, as the most volatile metal, precipitated last, just after potassium. According to our calculations, the top layer of the protocrust must have contained up to 1019 kg of metallic zinc, a powerful reductant.

The venting of hot geothermal fluids through this MVE-fallout layer, rich in metallic zinc and radioactive potassium, both capable of reducing carbon dioxide and dinitrogen, must have yielded a plethora of organic molecules released with the geothermal vapor.

n the pools of vapor condensate, the RNA-like molecules may have emerged through a pre-Darwinian selection for low-volatile, associative, mineral-affine, radiation-resistant, nitrogen-rich, and polymerizable molecules.

Origin of the RNA World in Cold Hadean Geothermal Fields Enriched in Zinc and Potassium: Abiogenesis as a Positive Fallout from the Moon-Forming Impact?, Life via PubMed (open access)

Astrobiology, Astrochemistry,

The search for life outside our solar system is at the forefront of modern astronomy, and telescopes such as the Habitable Worlds Observatory (HWO) are being designed to identify biosignatures.

Molecular oxygen, O₂, is considered a promising indication of life, yet substantial abiotic O₂ may accumulate from H₂O photolysis and hydrogen escape on a lifeless, fully (100%) ocean-covered terrestrial planet when surface O₂ sinks are suppressed.

This so-called waterworld false positive scenario could be ruled out with land detection because exposed land precludes extremely deep oceans (~50 Earth oceans) given topographic limits set by the crushing strength of rocks.

Land detection is possible because plausible geologic surfaces exhibit increasing reflectance with wavelength in the visible, whereas liquid water and ice/snow have flat or decreasing reflectance, respectively.

Here, we present reflected light retrievals to demonstrate that HWO could detect land on an exo-Earth in the disk-averaged spectrum. Given a signal-to-noise ratio of 20 spectrum, Earth-like land fractions can be confidently detected with 0.3-1.1 um spectral coverage (resolution R~140 in the visible, R~7 in the UV, with Earth-like atmosphere and clouds). We emphasize the need for UV spectroscopy down to at least 0.3 um to break an O₃-land degeneracy.

We find that the SNR and resolution requirements in the visible/UV imply that a larger aperture (~8 m) will be necessary to ensure the observing times required for land detection are feasible for most HWO terrestrial habitable zone targets. These results strongly inform the HWO minimum requirements to corroborate possible oxygen biosignatures.

Anna Grace Ulses, Joshua Krissansen-Totton, Tyler D. Robinson, Victoria Meadows, David C. Catling, Jonathan J. Fortney

Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2506.21790 [astro-ph.EP] (or arXiv:2506.21790v1 [astro-ph.EP] for this version)
https://doi.org/10.48550/arXiv.2506.21790
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Submission history
From: Anna Grace Ulses
[v1] Thu, 26 Jun 2025 22:12:38 UTC (1,517 KB)
https://arxiv.org/abs/2506.21790
Astrobiology,

Scientists analysing the cascading impacts of record low levels of Antarctic sea ice fear a loss of critical US government satellite data will make it harder to track the rapid changes taking place at both poles.

Researchers around the globe were told last week the US Department of Defence will stop processing and providing the data, used in studies on the state of Arctic and Antarctic sea ice, at the end of this month.

Tracking the state of sea ice is crucial for scientists to understand how global heating is affecting the planet.

Sea ice reflects the sun’s energy back out to space but, as long-term losses have been recorded, more of the planet’s ocean is exposed to the sun’s energy, causing more heating.

The National Snow and Ice Data Center, based at the University of Colorado, maintains a Sea Ice Index used around the world to track in near real-time the extent of sea ice around the globe.

In two updates in the past week, the centre said the US government’s Department of Defence, which owns the satellites that contain onboard instruments used to track sea ice, would stop “processing and delivering” the data on 31 July.

Climate scientists have been warning that Trump administration cuts have targeted climate functions across government, and there has been fears the sea ice data could be targeted.

The news comes as new research, some of which relied on the data, found that record low amounts of sea ice around Antarctica in recent years had seen more icebergs splintering off the continent’s ice shelves in a process scientists warned could push up global sea levels faster than current modelling has predicted.

Dr Alex Fraser, a co-author of the research at the Australian Antarctic Program Partnership (AAPP), said NSIDC’s sea ice data was “our number one heart rate monitor” for the state of the planet’s ice.

“It’s our early warning system and tells us if the patient is about to flatline. We need this data and now [the scientific community] will be forced to put together a record from a different instrument. We won’t have that continued context that we have had previously.”

NSIDC has said it is working with alternative and higher-resolution instruments from a different satellite, but has warned that data may not be directly comparable with the current instruments.

Fraser said: “We are seeing records now year on year in Antarctica, so from that perspective this could not have come at a worse time.”

The research, published in the journal PNAS Nexus, found a link between increasing numbers of icebergs calving from floating ice shelves and the loss of sea ice.

While the loss of sea ice does not directly raise sea levels, the research said it exposed more ice shelves to wave action, causing them to break apart and release icebergs faster.

Glaciologist Dr Sue Cook, also from AAPP, said “like a cork in a bottle” those shelves help to slow down the advance of land-based ice that does raise sea levels if it breaks off into the ocean.

She said the higher rates of iceberg calving seen in Antarctica were not accounted for in calculations of how quickly the ice sheet might break apart and contribute global sea levels.

“If we shift to this state where summer sea ice is very low but we continue using models based on previous periods, then we will definitely underestimate how quickly Antarctica will contribute to sea level rise,” she said.

The study also outlined other knock-on effects from the record low sea ice levels in the Antarctic, including the loss of more seals and penguins if trends continued.

As many as 7,000 emperor penguin chicks died in late 2022 after the early break-up of the stable ice they used for shelter while they grow their waterproof plumage.

Guardian Australia has requested comment from NSIDC and the US Department of Defence.

At the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), the 88-Inch Cyclotron is a powerful machine built to accelerate ions and explore the atomic nucleus. For decades, it has helped scientists probe the building blocks of matter.

There’s another side to this machine that is less well known but equally impactful: It’s an indispensable testbed for electronics, materials, and medical isotopes. By delivering beams of charged particles that can be tuned to different energies and compositions, the 88-Inch Cyclotron plays a surprising and wide-ranging role in science and technology – advancing energy technologies, helping spacecraft survive radiation, and improving cancer treatments.

In collaboration with companies, universities, and government partners, here are a few examples of how the 88-Inch Cyclotron has made modern technology more reliable, resilient, and revolutionary:

Ensuring Sturdy Satellites for GPS

Much of the 88-Inch Cyclotron’s work is in testing electronics components – think microchips and circuit boards – to make sure they can stand up to harsh environments. These efforts are concentrated at the Berkeley Accelerator Space Effects (BASE) Facility, which can emulate years of exposure to space radiation in just hours. Since pioneering this type of heavy ion testing in 1979, researchers have used the 88-Inch Cyclotron to test every generation of GPS – the system behind smartphone directions, app-based location services, shipping logistics, emergency response, and many more everyday applications. By assessing how cosmic rays deposit energy and damage electronics on satellites, manufacturers can then design resilient components to keep this crucial tool running smoothly.

Developing Tougher Materials for Fusion Energy

Nuclear fusion could provide a huge supply of power, but building a fusion plant that can handle the intense process requires solving fundamental engineering problems. Using an intense beam of high-energy neutrons produced by the 88-Inch Cyclotron, researchers and companies can test materials under consideration for fusion energy machines; for example: optics that focus the laser, structural materials, and the superconducting wire for magnets.

Previous tests at other facilities used X-rays, beams of charged particles, or low-energy neutrons, which don’t fully replicate the reactions from fusion. Berkeley Lab’s more realistic neutron beam helps teams know how their materials might respond with far greater accuracy, and, in turn, design more resilient equipment up to the challenge. “No one wants to use a poor surrogate for their tests if they can use what’s basically the real thing,” said Andrew Voyles, a UC Berkeley research engineer at the 88-Inch Cyclotron who leads that research program.

Getting Rockets Ready for Launch

To prepare for extreme conditions, launch vehicles like the Atlas, Delta, and Falcon rockets have tested their electronics at the BASE Facility. Prototype components undergo rigorous trials that reveal design vulnerabilities and allow for crucial improvements before launch. The impact of even a single high-energy particle – a “single event effect” – can disrupt or disable an unprotected microchip. BASE Facility research coordinator Mike Johnson estimates that over 90% of the U.S. spacecraft that have ever gone to space have at least some of their electronics evaluated at the 88-Inch Cyclotron.

Accelerating Access to Cancer Therapies

Actinium-225 is a promising isotope for targeted cancer treatments, but it’s notoriously difficult to produce. It has been called “the rarest drug on Earth,” with a global supply of about 1,000 doses a year. Researchers used the 88-Inch Cyclotron’s neutron beam to pioneer a new method to make the isotope more efficiently. The team also designed and tested a piece of equipment that industry can license and pair with the technique to produce actinium-225 in far larger quantities – potentially thousands of doses per week. In addition, experts at the facility research the optimal ways to make other medical isotopes used in PET scans, diagnostics, and potential treatments, and have shared that knowledge with industry and academic partners across the country.

“We do these basic measurements to find the optimum recipes for making these rare isotopes, then hand it off to production facilities that can start making it in large quantities,” Voyles said. “We sit at this intersection of really interesting scientific challenges with massive societal benefits on a time scale faster than you usually see in physics. It’s the best of both possible worlds: We get to do impactful work while figuring out some cool science in the process.”

Powering Space Science to Explore Our Universe

At the BASE Facility, researchers can tune the particle beam and adjust the “cocktail” of ions and energies to simulate different radiation conditions that you might find in low-Earth orbit, deep space, or on the surface of another planet. That adjustability helps space agencies like NASA, the European Space Agency (ESA), and the Japan Aerospace Exploration Agency (JAXA) assess their equipment as precisely as possible. The 88-Inch Cyclotron has tested electronics for dozens of high-profile missions, including multiple Mars rovers, the New Horizons mission to Pluto, and the James Webb Space Telescope. “We’ve tested parts for spacecraft that have gone to all the planets in the solar system,” Johnson said.

Keeping Astronauts and Missions Safe

When astronauts venture into space, the stakes are even higher. The 88-Inch Cyclotron has supported human spaceflight efforts for decades, testing electronics for the Space Shuttle, International Space Station, and spacesuits. Recently, it’s been used to evaluate the electronics in the latest generation of extravehicular mobility units, spacesuits designed for NASA’s Artemis program and future missions to the Moon and Mars. These tests help engineers identify how radiation might affect systems, allowing teams to troubleshoot and safeguard those technologies before astronauts rely on them in the field.

Lowering Costs for Molten Salt Reactors

Molten salt reactors are a next-generation nuclear energy design that use liquid salts (similar to sodium chloride, or table salt) to transfer heat and eventually create electricity. Designers had theorized that chlorine isotope impurities in the salt might absorb too many neutrons, limiting reactor performance – and filtering out the impurities was expected to cost hundreds of millions of dollars. But the reaction had never been tested directly. Using a neutron beam at the 88-Inch Cyclotron, researchers measured the process and found that the impact was negligible. Filtering the chlorine wouldn’t be necessary, saving potential commercial developers money and making molten salt reactors more viable.

Supporting National Defense with Hardened Tech

Electronics used in national defense systems must withstand extreme conditions. The Missile Defense Agency and Test Resource Management Center are among those who use the BASE Facility to test and strengthen critical components. By replicating challenging radiation environments, the cyclotron ensures that these systems remain reliable under stress. “Even on land, depending on what a computer is doing, you might have sensitive parts,” Johnson said. “It highlights the importance of this kind of testing. Whether damaging particles come from the sun or a nuclear incident, if you have these parts fail, you could lose crucial systems.”

Making Travel Safer by Testing Parts for Cars and Planes

While much of the 88-Inch Cyclotron’s testing focuses on electronics destined for space, its capabilities are also important for systems on Earth that require high reliability and safety. Modern commercial aircraft and vehicles rely on increasingly complex electronics, from autonomous navigation systems and flight control computers to advanced driver-assist features in cars. These systems must be able to withstand single event effects from cosmic rays that find their way to Earth. Companies working on aviation and automotive technologies use the BASE Facility to rapidly put their electronics through their paces.

Quantum dots infuse a machine vision sensor with superhuman adaptation speed.

WASHINGTON, July 1, 2025 — In blinding bright light or pitch-black dark, our eyes can adjust to extreme lighting conditions within a few minutes. The human vision system, including the eyes, neurons, and brain, can also learn and memorize settings to adapt faster the next time we encounter similar lighting challenges.

In an article published this week in Applied Physics Letters, by AIP Publishing, researchers at Fuzhou University in China created a machine vision sensor that uses quantum dots to adapt to extreme changes in light far faster than the human eye can — in about 40 seconds — by mimicking eyes’ key behaviors. Their results could be a game changer for robotic vision and autonomous vehicle safety.

“Quantum dots are nano-sized semiconductors that efficiently convert light to electrical signals,” said author Yun Ye. “Our innovation lies in engineering quantum dots to intentionally trap charges like water in a sponge then release them when needed — similar to how eyes store light-sensitive pigments for dark conditions.”

The sensor’s fast adaptive speed stems from its unique design: lead sulfide quantum dots embedded in polymer and zinc oxide layers. The device responds dynamically by either trapping or releasing electric charges depending on the lighting, similar to how eyes store energy for adapting to darkness. The layered design, together with specialized electrodes, proved highly effective in replicating human vision and optimizing its light responses for the best performance.

“The combination of quantum dots, which are light-sensitive nanomaterials, and bio-inspired device structures allowed us to bridge neuroscience and engineering,” Ye said.

Not only is their device design effective at dynamically adapting for bright and dim lighting, but it also outperforms existing machine vision systems by reducing the large amount of redundant data generated by current vision systems.

“Conventional systems process visual data indiscriminately, including irrelevant details, which wastes power and slows computation,” Ye said. “Our sensor filters data at the source, similar to the way our eyes focus on key objects, and our device preprocesses light information to reduce the computational burden, just like the human retina.”

In the future, the research group plans to further enhance their device with systems involving larger sensor arrays and edge-AI chips, which perform AI data processing directly on the sensor, or using other smart devices in smart cars for further applicability in autonomous driving.

“Immediate uses for our device are in autonomous vehicles and robots operating in changing light conditions like going from tunnels to sunlight, but it could potentially inspire future low-power vision systems,” Ye said. “Its core value is enabling machines to see reliably where current vision sensors fail.”

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Article Title

A back-to-back structured bionic visual sensor for adaptive perception

Authors

Xing Lin, Zexi Lin, Wenxiao Zhao, Sheng Xu, Enguo Chen, Tailiang Guo, and Yun Ye

Author Affiliations

Fuzhou University, Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China

For over a decade, NASA’s Curiosity rover has been capturing images of Mars as scientists continue to study the planet’s structures and surface.

Curiosity’s goal as it travels across Mars is to look for unique signs of life, including signs of possible ancient life on the planet.

What is it?

A vast cloud of energetic particles surrounding a cluster of galaxies that existed around four billion years after the Big Bang could help scientists discover how the early universe took shape.

But was the halo of the massive cluster of galaxies — called SpARCS104922.6+564032.5, and located 9.9 billion light-years from Earth— built by erupting supermassive black holes or a cosmic particle accelerator?