Antikythera mechanism

Ancient Greek analogue astronomical computer

The Antikythera mechanism ( AN-tik-ih-THEER-ə, US also AN-ty-kih-) is an ancient Greek hand-powered orrery (model of the Solar System) built in the 2nd century BC and discovered in 1901. It is the oldest known example of an analogue computer. It could be used to predict astronomical positions and eclipses decades in advance.

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