Astrolabe

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A diagram of an astrolabe shows the different parts of the instrument. The mater was the base plate. It had a network of lines representing the positions of objects in the sky. It also had tools to measure the hours of the day. Other important parts were an open-pattern disk (the rete) with a "map" of the stars, and a straight rule (the alidade), used for sighting objects in the sky.

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Size: 1600px × 1433px
Photo credit: © Encyclopaedia Britannica Inc. / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: alidade, astrolabe, astronomy, clock, cosmic, device, diagrams, horology, mater, observation, rete, solar, time, timekeeping, timepiece, tympan