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Dark matter particles may exert a hidden force on one another, but its effects are stranger than expected。 An extra attraction helps the particles cluster, yet it also makes dark matter effectively lighter as the Universe expands。 That weakens its gravitational impact and usually slows the growth of cosmic structure rather than accelerating it
Boy's unusual symptoms could help identify the next case sooner
James Webb has captured a striking new infrared view of NGC 2392, the Lion Nebula, revealing the dramatic aftermath of a dying Sun-like star。 At its center, a scorching white dwarf is blasting radiation into surrounding gas and dust, carving out the nebula’s lion-like face while illuminating a sprawling “mane” of surviving dusty clumps
Scientists have demonstrated that heat can move through a crystal in focused, wave-like rays at room temperature instead of spreading randomly。 The breakthrough could make it possible to route heat around sensitive parts of next-generation chips and quantum devices
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
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’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
A black hole observed during a dramatic 2023 eruption did not simply devour gas from its nearby companion star。 It also expelled large amounts of material through powerful jets and winds, even after the outburst had nearly faded。 The results suggest black holes may continue reshaping their surroundings long after their brightest fireworks end
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 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
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
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
Scientists have discovered incredibly tiny plasma whirlpools swirling across the Sun’s surface, some just 20 kilometers wide。 These previously invisible vortices may twist magnetic fields and help build up the energy released in small solar eruptions called nanoflares。 They may also help magnetic fields spread through the Sun’s atmosphere far faste
AI firms quietly bulk buying rare books face resistance from booksellers
Hundreds of Homeland Security drones retasked to survey wildlife and livestock
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
Scientists have built the first all-optical photonic time crystal, allowing them to reshape the behavior of terahertz light at extraordinary speeds。 The breakthrough could open the door to ultrafast computing, smarter communication systems, advanced imaging, and a new generation of highly tunable lasers
A supermassive black hole has been found lurking about 30,000 light-years from the center of its galaxy—the first dormant black hole detected so far from a galactic core。 It revealed itself only after shredding a passing star and producing a brief, brilliant flare。 Astronomers think it may be the remnant of a devoured galaxy or a black hole flung o