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unusual facts about Pfund sky compass



August Herman Pfund

He also invented the Pfund telescope, which is a method for achieving a fixed telescope focal point regardless of where the telescope line of sight is positioned, and the Pfund sky compass, which arose from Pfund's studies of the polarization of scattered light from the sky in 1944, and which greatly helped transpolar flights by allowing the determination of the Sun's direction in twilight.


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