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in case you want to file this away for your "new calendar" or other time-related project:
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Lego machine predicts future eclipses - Hack a Day
Hidden behind the white face plates of this machine are racks of gears that make up a replica of one of the oldest known mechanical computers. This is a working model of the Antikythera mechanism made from Lego pieces. In the video, the machine is disassembled into its various components. Each mechanical unit takes advantage of gear ratio combinations to perform numerous levels of mathematical functions in order to display the date and time that future celestial events will occur.
Believed to date back to 100-150 BC, the stone bronze mechanism was recovered from a shipwreck around the turn of the twentieth century. The use of x-ray analysis helped to unlock the functions and confirm the theories of its operation.
Want more of the Antikythera mechanism? Check out the model built by Tatyana van Vark.