ProPublica: The US Transportation Security Administration has quietly begun removing its x-ray “backscatter” scanners from some airports. The machines are being replaced by millimeter-wave scanners, which use low-energy radio waves. The switch is intended to speed up security checkpoints because the new machines do not require staff to visually evaluate the scanners’ images. The x-ray scanners raised concerns over privacy and faced criticism concerning the radiation dose travelers were exposed to. Although there are no health concerns with the millimeter-wave scanners, which use cellphone-like signals, some tests have shown that they have higher false-positive detection rates.
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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