Nature: A Viking legend tells of a glowing “sunstone” that, when held up to the sky, revealed the position of the Sun even on a cloudy day, writes Jo Marchant for Nature. It sounds like magic, but scientists measuring the properties of light in the sky say that polarizing crystalswhich function in the same way as the mythical sunstonecould have helped ancient sailors to cross the northern Atlantic. A review of their evidence is published today in Philosophical Transactions of the Royal Society B.
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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