The Antikythera mechanism is an ancient analog computer designed to calculate astronomical positions. It was recovered in 1900, but it's significance and complexity were not understood until a century later.
The device is extraordinary, in terms of historic and scarcity value, this mechanism is more valuable than any piece of art imaginable. The Antikythera mechanism is kept at the National Archaeological Museum of Athens. It is now displayed at the temporary exhibition about the Antikythera Shipwreck.
This machine has the oldest known complex gear mechanism and is sometimes called the first known analog computer. The mechanism was operated by turning a small hand crank (now lost) which was linked via a crown gear to the largest gear.
The action of turning the hand crank would also cause all interlocked gears within the mechanism to rotate, resulting in the calculation of the position of the Sun and Moon and other astronomical information, such as moon phases, eclipse cycles, and theoretically the locations of planets.
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