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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
Chemists have developed a catalyst that breaks a long-standing rule governing which molecules receive electrons during chemical reactions。 By releasing electrons directly into solution, the technique could unlock reactions—and potentially useful new molecules—that were previously out of reach
The solar wind may be stripping away Mars’ atmosphere by creating giant rolling waves along its outer edge。 Data from MAVEN and Tianwen-1 show that these waves form plasma clouds that carry atmospheric particles into space。 The process is concentrated on one side of Mars and may have played a major role in drying out the once potentially habitable
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
Primordial black holes may occasionally pass through white dwarf stars and trigger enormous Type Ia supernova explosions。 Researchers found that these events could explain chemical patterns seen in supernova remnants, nearby explosions, and stars across the Milky Way
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%
Scientists traced a mysterious surge of low-energy gamma rays from zinc-70 to magnetic changes occurring inside its nucleus。 The breakthrough could improve models of how stars, supernovae, and neutron star mergers create heavy elements
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
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
Companies treat some email domains as digital trash cans, despite the risks
Engineers have transformed a notoriously brittle cobalt-aluminum compound into a material that is both extremely strong and capable of bending without breaking。 Their nanoscale design produced a yield strength about six to 10 times greater than high-strength structural steel while sustaining substantial deformation at room temperature。 The approach
NASA’s Curiosity rover has entered a Martian valley covered by an astonishing “sea” of tiny polygon-shaped fractures。 The honeycomb patterns, each only a few inches wide, stretch across the landscape and even wrap around a nearby 20-foot-tall butte
Ultrafast X-rays revealed how a molecule converts absorbed light into motion in just trillionths of a second。 Individual atoms recorded different stages of the process, opening a powerful new window into light-driven chemistry
Hidden moon ice may reveal itself through the way it bends and reflects vibrations from moonquakes。 The technique could help astronauts locate vital water supplies and uncover clues about the origins of Earth’s oceans
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