A corroded mass of gears and dials recovered from the sea over 100 years ago has long been a mystery. In 1902, an ancient Greek shipwreck near the island of Antikythera gave up one of its treasures: 81 shards of a complex and precise mechanism. Although scientists dated it to 150-50 B.C., its original purpose has remained a mystery - until now.
A former curator of the Science Museum in London, Michael Wright, has built a replica of the Antikythera mechanism that works perfectly. A single knob on the side rotates a complex system of gears and dials. It tracks the movements of the planetary bodies as well as predicts lunar and solar eclipses. An upper dial shows lunar months in the 19-year cycle that reconciles the lunar year to the solar year. The artifact is an amazing manually operated time-computer. The face of the box shows the earth with the various planets rotating around it and the moon going through its phases. The device even accommodates the planets' varying anomalies in their individual orbits.
In a short documentary, Michael Wright demonstrates how the replica operates. Wright's is the first model made of the Antikythera mechanism that includes all known features of the device. The BBC is calling it a "moon computer".