Researchers at the University of Cambridge and spin-out GlitterinTech have built an optical spectrometer that costs about $10 and measures a few centimetres across. The device reads how light interacts with a substance and identifies foods, plastics and medicines with 100% accuracy in tests. The team says it can also track blood glucose, alcohol and other markers without a needle. Instead of spreading light with a prism or grating, it applies a convolution directly to incoming light, which the researchers say preserves range and resolution at small size. Industrial quality control and food testing are early uses; field results are not yet published.
A study in Astronomy & Astrophysics used carbon monoxide observations, largely from the ALMA telescope, to estimate the carbon-to-oxygen ratio deep inside Uranus and Neptune. Neptune appears substantially richer in oxygen than Uranus, which points to a lower carbon-to-oxygen ratio there. The authors say that split is hard to explain if both planets formed from the same material in the same part of the early solar system. One scenario has Uranus forming near its current orbit and Neptune forming closer to the Sun before migrating outward. Only Voyager 2 has ever flown past either world. The authors say vertical mixing in the deep atmospheres remains the largest source of uncertainty.
Researchers at the University of Bonn and University Hospital of Bonn converted immature red blood cells from an 80-year-old donor directly into neural stem cells, skipping the pluripotent stage, and found the cells carried epigenetic age marks of someone under 20. Rejuvenation was gradual and tracked for over 100 days, with about 60 years erased after 50 days. The slow reset gives scientists a model to test which molecules speed up or slow cellular ageing, which matters for Alzheimer's research because age is the strongest risk factor. The study, in Aging Cell, does not offer a treatment for ageing in people.
The Orionid meteor shower reaches its peak on the night of October 21 and the morning of October 22. The meteors are dust shed by Halley's Comet, which passed through the inner solar system in 1986 and will not return until 2061. NASA says a bright Moon will wash out some of the fainter streaks this year, and the best viewing window is the hours before dawn, after the Moon sets. The shower radiates from the constellation Orion, which rises in the east after midnight.
Japan launched its Martian Moons eXploration spacecraft on Tuesday aboard an H3 rocket from Tanegashima, aiming to return the first samples from Phobos. Liftoff was at 4:41 a.m. local time. The 4,480-kilogram probe will spend about three years in the Martian system, mapping both moons and then landing on Phobos to collect at least 10 grams of material. A capsule is due back on Earth in 2031. Scientists hope the samples will show whether the moons are captured asteroids or debris from an impact on Mars.
Scientists at the University of Cambridge tested 39 sweeteners against 25 species of gut bacteria and found that about three-quarters altered the growth of at least one species. Some slowed or stopped microbes associated with a healthy digestive system. The strongest effect came when the sweetener isosteviol was combined with the antidepressant duloxetine, which suppressed two bacteria involved in digestion and blood sugar regulation and disturbed a simulated microbiome. The study, published in Molecular Systems Biology, was done in the laboratory rather than in people, and the authors say more work is needed before drawing conclusions about human health.
NASA says its Nancy Grace Roman Space Telescope is producing images nearly 30% sharper than predicted after engineers moved a mirror by about one-sixteenth the width of a human hair. The Wide Field Instrument, activated in September, was tested detector by detector, then calibrated with its own internal LEDs. The instrument is central to Roman's surveys of dark matter and dark energy. Engineers say the extra sharpness will make measurements of distant galaxy shapes more accurate.
A RIKEN-led team reported single-qubit gate fidelities above 99.99 percent across a five-qubit silicon spin array, with some measurements near 99.999 percent, in a study published in Nature Physics. Crucially, the fidelities held while up to three qubits ran simultaneously on one shared microwave control line. The researchers traced crosstalk in the array and used tailored Kaiser-window pulses plus pairwise phase calibrations to suppress it. When all five qubits operated in parallel, fidelity stayed at the 99.9 percent fault-tolerant threshold or above. Silicon spin qubits can be made with standard CMOS chip tools.
A new radiocarbon dating campaign along the Qhapaq Nan, the Inca road system, is rewriting a timeline that rested on Spanish colonial records. Researchers used accelerator mass spectrometry to date material from sites across the Andes and found the empire lasted longer than the written accounts suggest, and that it met more resistance as it expanded. The work appears in this week's issue of Science. Earlier dating of Machu Picchu already showed the site was in use decades before the colonial record said.
Thousands of Adelie penguins found dead at Antarctica's Danger Islands in March 2024 were victims of avian cholera, not the H5N1 bird flu that scientists first suspected, according to a new study. Researchers swabbed and collected tissue from 49 carcasses and found the bacterial disease was the most likely cause of death for most adults examined. Genetic analysis showed the strain has circulated in Antarctica for more than two decades. The authors say avian cholera should be included in future wildlife surveillance alongside bird flu. The work was published by the Royal Society and involved researchers from the University of California, Davis.