Rocks from a South China section record an extreme burst of geomagnetic polarity reversals−about 11 per million years−across the end-Guadalupian mass extinction roughly 261 million years ago. The rate is among the highest known in Earth’s history. Researchers speculate the instability may reflect deep-mantle changes that briefly weakened magnetic shielding, adding stress to an already troubled biosphere, though a direct causal role remains unproven.

Do cosmic radiation doses near the Moon differ significantly from those received by astronauts in low Earth orbit? Experimental lithium fluoride detectors, installed aboard the Orion spacecraft during the Artemis I mission, have now made it possible to obtain preliminary estimates.

Baby manta rays escape predators by avoiding them until they grow large enough for a face-off, a new study has found. Tracking data shows that young giant manta rays in Central America strictly stick to comparatively safe coastal areas for the first few years of their life. When they’re large enough that natural enemies are a lesser concern, they leave these sanctuaries and embark on journeys spanning hundreds of kilometers. This shift in space use allows mantas to grow in safety before facing another type of danger in the open oceans: industrial fisheries and vessel strikes in unprotected waters. The authors say underwater corridors are needed to protect adult mantas on their treks.

Satellite sun-induced chlorophyll fluorescence (SIF) can track photosynthesis from space, but canopy structure can distort the signal. 

Manipulating high-dimensional structured light is crucial for next-generation informatics, yet traditional systems remain bulky and lack reconfigurability. The research team led by Prof. Minming Zhang developed a fully tunable silicon-integrated meta-generator merging waveguide mode multiplexing with multi-channel coherent control. This chip achieves dynamic generation and full-surface coverage across multiple Poincaré spheres, successfully mapping on-chip modes to free-space structured fields for advanced optical communications and quantum technologies.