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Ordinary WiFi networks could quietly become powerful surveillance tools, allowing people to be identified without cameras, special sensors, or even carrying a connected device。 Researchers showed that unencrypted signals routinely exchanged between WiFi devices and routers can be used to create radio-based images of people and recognize them within
A person’s sleeping brain may reveal warning signs of dementia long before memory problems begin。 Researchers used machine learning to analyze EEG recordings from about 7,000 adults and found that an older-than-expected “brain age” was tied to a sharply higher dementia risk。 Every additional 10 years of brain aging raised that risk by nearly 40%
Cassini data has revealed a surprising twist in Saturn’s magnetic shield: the planet’s rapid rotation appears to drag a key opening in its magnetosphere far toward the afternoon side instead of keeping it near noon, as happens on Earth。 The finding confirms that giant planets like Saturn operate under a fundamentally different magnetic regime, wher
A new hollow nanoreactor mimics living cells to make hydrogen peroxide more efficiently using visible light。 Its light-trapping cavity and proton-shuttling shell could open new possibilities for cleaner chemical manufacturing and artificial photosynthesis
Metal-rich asteroids could one day become hardware stores for Mars, supplying the materials needed to build and repair a growing colony。 A new analysis shows that carefully selected asteroids may be reachable with current spacecraft technology。 Some could even provide the ingredients for making rocket fuel in space, dramatically reducing the burden
Silver nanocatalysts have been found to switch where they perform their most important reactions depending on whether a solid oxide cell is making electricity or hydrogen。 The discovery could enable smarter catalyst designs that boost clean power generation while making green hydrogen more energy-efficient
A new 3D printing technique can produce exceptionally hard tungsten carbide cobalt while using less of its expensive raw materials。 By softening rather than fully melting the material, researchers created defect-free samples with industrial-grade hardness and opened the door to more efficient manufacturing
NASA is assembling the foundations of a future Moon Base through a wave of robotic missions and powerful new commercial landers。 More than 20 landings are planned through 2029, testing everything from precision landings and lunar communications to rovers, power systems, and technology that can survive the Moon’s extreme conditions。 Upcoming mission
Researchers have found a clever new way to map a part of Earth’s upper atmosphere that is notoriously difficult to observe。 Using orbital data from roughly 1,200 Starlink satellites, they reconstructed changes in atmospheric density about 500 kilometers above Earth。 The approach could sharpen satellite tracking and help reduce the growing risk of c
Hundreds of Homeland Security drones retasked to survey wildlife and livestock
Some black holes roaming the Universe today may actually be older than the Big Bang。 A new cosmic “bounce” model suggests the Universe expanded from an earlier contracting phase, allowing ancient black holes to survive the transition as cosmic fossils。 These relics could potentially explain dark matter and why surprisingly massive objects appeared
A new nanostructured carbon design lets fuel-cell catalysts use tiny amounts of platinum while remaining remarkably stable and efficient。 The breakthrough could help hydrogen fuel cells become a more practical way to power data centers, vehicles, and other energy-intensive technologies
A mathematician working at Anthropic says he used the AI model Claude Fable 5 to uncover a remarkably simple counterexample to the Jacobian conjecture, a famous problem that has resisted mathematicians for more than a century。 The result shows that the conjecture is false in three dimensions and above, although the original two-dimensional version
Scientists have created the first quantum material that can sort and transport different quantum states of light at room temperature, potentially removing the need for bulky, ultra-cold refrigeration systems。 Built from a gold film carved with hundreds of microscopic structures, the ultrathin “metacrystal” acts like a filter that directs different
Scientists have successfully generated electricity with a hydrogen turbine that produces its own pressure through detonation waves instead of relying on a mechanical compressor。 The breakthrough could unlock dramatically more efficient power systems for clean energy and future aviation
Photons traveling through a cloud of atoms can emerge so early that they appear to have spent a negative amount of time inside。 Researchers tested whether this was merely a misleading feature of the light pulse by making extremely weak measurements of the atoms。 Surprisingly, the atoms confirmed the same negative dwell time
August brings four major celestial events, including a solar eclipse and the peak of the Perseid meteor shower。 Dark New Moon skies could make the Perseids especially impressive, while Venus will blaze in the west after sunset。 A deep partial lunar eclipse closes the month, darkening most of the Moon
Mathematicians have shown that no electoral system can perfectly balance local representation, proportional national results, and a fixed-size parliament once enough parties compete。 A newly proposed voting method could soften these unavoidable trade-offs and produce outcomes that are much closer to fair