New York Times: An Israeli scholar says he has identified the first known physical sample of tekheletthe shade of blue used for ritual prayer tassels and for ceremonial robes worn by high priests. Zvi Koren, a professor specializing in the analytical chemistry of ancient colorants, analyzed a 2000-year-old piece of dyed fabric recovered from Masada, King Herod’s Judean Desert fortress. The exact shade of blue used has been a mystery for centuries. The dye was produced from the secretion of the sea snail, still found on Israeli beaches, but the technique of producing the dye was lost some time after the Jews were exiled from Israel in AD 70.
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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