BBC: At night, ozone, carbon monoxide, and other pollutants emitted by cars and factories are broken down by highly reactive nitrate radicals. That cleanup operation would be more effective if upward-pointing street lights didn’t destroy nitrate radicals, argued Harald Stark of the US National Oceanic and Atmospheric Administration in a talk he gave at this week’s meeting of the American Geophysical Union. Stark and his colleagues reached that conclusion after analyzing data gathered from aircraft flying over Los Angeles.
The finding that the Saturnian moon may host layers of icy slush instead of a global ocean could change how planetary scientists think about other icy moons as well.
Modeling the shapes of tree branches, neurons, and blood vessels is a thorny problem, but researchers have just discovered that much of the math has already been done.
January 29, 2026 12:52 PM
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