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The asteroid that wiped out the dinosaurs was likely an exceptionally rare CO chondrite from a distant region of the solar system。 Its unusual chemistry suggests that planet-cooling dust and debris, rather than sulfur inside the asteroid, may have delivered the deadliest blow
Early humans in England crafted a rare piece of elephant bone into a reusable hammer for sharpening stone tools nearly 500,000 years ago。 The extraordinary find reveals that ancient toolmakers were resourceful, skilled, and capable of surprisingly advanced planning
Giant sequoias are built to withstand ordinary fires, but recent extreme wildfires killed thousands of trees that had survived for centuries or even millennia。 A new analysis of about 26,400 sequoias found that trees in areas treated with prescribed burns were nearly four times more likely to survive。 Researchers estimate the controlled fires preve
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
Young Jupiter’s powerful magnetic field may have created a safe zone where several large moons could survive。 Saturn lacked this protection, possibly explaining why Titan stands almost alone among its largest moons
Physicists have uncovered a surprising limit to electrical resistance caused by particles colliding。 Using ultracold potassium atoms trapped in a grid of light, researchers created a highly controlled stand-in for electrons moving through a solid。 As collisions became more frequent and intense, resistance initially rose, but eventually hit a ceilin
Scientists have identified LHAASO J1912+1014u as a cosmic accelerator that can push protons beyond one quadrillion electron volts。 The finding may help reveal where the Milky Way’s most energetic cosmic rays come from and how they influence the galaxy
NASA’s Swift Observatory observed a supermassive black hole ripping apart a star more than 30,000 light-years from the center of a distant galaxy。 The extraordinary flare briefly outshone its entire host galaxy in ultraviolet light and revealed a black hole about a million times the Sun’s mass
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
Sweden could become an important source of rare earth elements needed for magnets and green technologies。 Instead of extracting one target metal, researchers are cataloging everything contained in Swedish mineral deposits。 They will then develop magnets using those naturally available combinations, potentially reducing pollution, waste, and relianc
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Scientists have created twisted laser beams that interact differently with right-handed and left-handed molecules, revealing their identity through the fragments they produce。 The approach could provide a faster, simpler, and more sensitive way to analyze important molecules used in chemistry and pharmaceuticals
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
NASA astronaut Chris Williams and two Roscosmos cosmonauts are back on Earth after spending 241 days aboard the International Space Station。 Their journey covered more than 102 million miles and included 3,856 trips around the planet
Astronomers may have been listening for alien civilizations in only a small slice of the radio spectrum while overlooking a largely unexplored range of higher frequencies。 Using archived data from the ALMA telescope in Chile, researchers conducted the observatory’s first SETI survey, searching for narrow signals that could indicate advanced technol
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%