For decades, it’s been known that subtle chemical patterns exist in metal alloys, but researchers thought they were too minor to matter—or that they got erased during manufacturing. However, recent studies have shown that in laboratory settings, these patterns can change a metal’s properties, including its mechanical strength, durability, heat capacity, radiation tolerance, and more.
Now, researchers at MIT have found that these chemical patterns also exist in conventionally manufactured metals. The surprising finding revealed a new physical phenomenon that explains the persistent patterns.
In a paper published in Nature Communications today, the researchers describe how they tracked the patterns and discovered the physics that explains them. The authors also developed a simple model to predict chemical patterns in metals, and they show how engineers could use the model to tune the effect of such patterns on metallic properties, for use in aerospace, semiconductors, nuclear reactors, and more.
For decades, scientists have observed, but been unable to explain, a phenomenon seen in some soft materials: When force is applied, these materials exhibit not one, but two spikes in energy dissipation, known as overshoots. Because overshoots are generally thought to indicate the point at which a material yields, or transitions from solid-like to fluid-like behavior, the dual response was therefore assumed to indicate “double yielding”—the idea that to fully fluidize a material, it needed to yield twice.
Now, researchers at the University of Illinois Urbana-Champaign have shown that this behavior is different than previously hypothesized. Their paper, “Resolving Dual Processes in Complex Oscillatory Yielding,” is published in Physical Review Letters.
In the study, chemical and biomolecular engineering professor Simon A. Rogers and his team, led by then-graduate student James J. Griebler show that the two-step response is the result of two independent processes: first, a softening of the material’s elastic structure, and later, true yielding.
The Royal Swedish Academy of Sciences has decided to award the 2025 Nobel Prize in chemistry to Susumu Kitagawa, Richard Robson and Omar M. Yaghi \.
Not all stars are created equally. Astronomers believe that the first stars to form after the Big Bang were mostly made of only hydrogen and helium with trace amounts of lithium, as the heavier elements formed later on by nuclear fusion inside the stars. When these stars went supernova, heavier elements spread throughout space and formed more stars. Each successive generation contained more heavy elements, and these elements also became successively heavier.
While most stars still contain mostly hydrogen and helium, they now contain many heavy elements as well, especially as they get older. These elements show up in spectrographic data when astronomers gather light from these distant stars. Stars are considered “pristine” when the data shows a lack of heavy elements—meaning they are likely very rare, older stars from earlier generations. And now, a group of astronomers, led by Alexander Ji from the University of Chicago, believe they have found the most pristine star on record. The group has documented their findings on the arXiv preprint server.
The star, referred to as SDSS J0715-7334, is a red giant purported to have the lowest metallicity—or heavy element content—ever found. The team’s detailed spectral and chemical analysis shows that SDSS J0715-7334 has a total metallicity “Z” of less than 7.8 × 10-7. This is compared to the next lowest metallicity star currently known, a star located in the Milky Way with a total metallicity of around 1.4 × 10-6.
Scientists digging through data collected by the Cassini spacecraft have found new complex organic molecules spewing from Saturn’s moon Enceladus. This is a clear sign that complex chemical reactions are taking place within its underground ocean. Some of these reactions could be part of chains that lead to even more complex, potentially biologically relevant molecules.
Published in Nature Astronomy, this discovery further strengthens the case for a dedicated European Space Agency (ESA) mission to orbit and land on Enceladus.
In 2005, Cassini found the first evidence that Enceladus has a hidden ocean beneath its icy surface. Jets of water burst from cracks close to the moon’s south pole, shooting ice grains into space. Smaller than grains of sand, some of the tiny pieces of ice fall back onto the moon’s surface, while others escape and form a ring around Saturn that traces Enceladus’s orbit.
For millions of years, a fragment of ice and dust drifted between the stars—like a sealed bottle cast into the cosmic ocean. This summer, that bottle finally washed ashore in our solar system and was designated 3I/ATLAS, only the third known interstellar comet. When Auburn University scientists pointed NASA’s Neil Gehrels Swift Observatory toward it, they made a remarkable find: the first detection of hydroxyl (OH) gas from this object, a chemical fingerprint of water.
Swift’s space-based telescope could spot the faint ultraviolet glow that ground observatories can’t see—because, high above Earth’s atmosphere, it captures light that never reaches Earth’s surface.
Detecting water—through its ultraviolet by-product, hydroxyl—is a major breakthrough for understanding how interstellar comets evolve. In solar-system comets, water is the yardstick by which scientists measure their overall activity and track how sunlight drives the release of other gases. It’s the chemical benchmark that anchors every comparison of volatile ices in a comet’s nucleus.