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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
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 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
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
AI firms quietly bulk buying rare books face resistance from booksellers
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
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
A rare meteorite that crashed through a New Jersey roof contains evidence of ancient salty fluids, organic compounds, and amino acids from a primitive asteroid。 Its pristine chemistry could offer new clues about how space rocks helped supply early Earth with some of the ingredients needed for life
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%
Let's shield the astronauts instead of the spacecraft
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
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
When atomic nuclei smash together at nearly the speed of light, they create the hottest fluid in the universe, but scientists may have overlooked one of its most important forces。 New simulations reveal that extreme acceleration builds up along the edges of quark-gluon plasma, helping drive its explosive expansion。 This acceleration may do far more
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
Physicists have found a new way to peer inside one of matter’s most elusive quantum states: the Wigner crystal, where electrons stop behaving like independent particles and organize into a crystal-like pattern。 By shining light on an atomically thin material cooled close to absolute zero, researchers uncovered optical signals that reveal not just w