Physics, astronomy and space science.
A new framework suggests that the supermassive black holes seen less than 700 million years after the Big Bang may have begun as unusually large seeds. It makes testable predictions for observations with the James Webb Space Telescope and future gravitational-wave detectors.
The MAJIS instrument aboard the European Space Agency’s JUICE spacecraft performed well during its August 2024 Earth-Moon gravitational assist. Tests supported its updated wavelength calibration and showed that its brightness measurements were close to expected values, strengthening confidence in future observations around Jupiter.
A study finds that loosely structured water molecules at the ice surface contribute to its low friction by forming a liquid-like, disordered layer. Three diamond-like carbon coatings reduced friction more than bearing steel, with the largest reduction reaching 58.6%.
Wild relatives contain adaptive genetic diversity that was reduced during crop domestication, but conventional prediction methods often miss complex DNA changes. A review in BMC Genomics outlines how artificial intelligence and broader genetic maps could help identify these variants for climate-resilient breeding.
A review examines how pulsating stars in eclipsing binary systems can be used to study stellar interiors and the effects of tides. Space-based observations, combined with repeated measurements of starlight spectra, can provide model-independent masses and radii for thousands of systems.
Researchers observed sound waves moving ballistically through a disordered acoustic lattice even though the system’s wave states were strongly localized at irregular positions. The result separates localization of wave states from the movement of wave packets.
Researchers developed an imaging approach that reconstructs label-free, three-dimensional subcellular detail in thick, highly scattering biological samples. Tests on model samples and biological specimens showed that specific measurement and calculation choices produced high-quality maps of the samples’ internal optical properties.
Finding oxygen or methane in a rocky exoplanet’s atmosphere would not by itself show that life is present. A study in Astrobiology finds that a proposed space telescope would need to examine light from near-ultraviolet through near-infrared wavelengths to assess habitability and investigate nonbiological explanations.
Globular clusters around the Milky Way reveal evidence of a previously identified but debated merger that occurred about 1.8 billion years before the Gaia-Sausage-Enceladus merger. The incoming system had a similar stellar mass and deposited most of it in the Milky Way’s inner 6 kiloparsecs.
A tabletop laser system produced tunable extreme-ultraviolet and soft-X-ray harmonics for potential use in resonant imaging and spectroscopy. The work could make some experiments less dependent on large free-electron-laser facilities, although the abstract does not report a direct imaging or spectroscopy demonstration.
Chemical and isotopic evidence from a silicate inclusion in the Aletai iron meteorite links IIIE iron meteorites with HED meteorites. The findings provide physical evidence that the metal core and rocky mantle of an early asteroid shared a common origin.
A 36.7-milligram ion-powered microrobot achieved controlled flight, hovering and sensing without mechanical moving parts. The experimental robot carried two sensors and completed predefined tasks while tethered hovering lasted up to one hour.
A major new review in particle physics compiles measured properties of major particle types, including the recently discovered Higgs boson. It adds 3,200 new measurements from 903 papers and updates many tables and reviews covering known particles and searches for hypothetical ones.
A review of evidence from Earth’s Hadean era and experiments on prebiotic chemistry finds that no single environment on early Earth appears to meet all the conditions needed for life to begin. Instead, the paper argues that multiple, connected processes across different settings likely helped build and stabilize the molecules that later became biology.
Researchers report a way to convert single infrared photons into targeted visible colors more efficiently and with much faster response. In NaYS2:Ho3+, they selectively enhance upconversion emissions by 2–3 orders of magnitude and cut response time from 30 ms to 54 μs, then demonstrate rapid, narrowband photodetection for low-threshold CO2 sensing.
