Tuesday, May 17, 2011
From The Writer's Almanac
On this day in 1902, archaeologist Valerios Stais discovered the Antikythera mechanism, an ancient analog computer from the first or second century B.C., that was used to calculate the position of the sun, moon, and stars in relationship to the observer’s position on the surface of the earth. For many decades, archaeologists did not recognize the mechanism’s degree of mechanical sophistication, which is comparable to a 19th-century Swiss clock. To date, the only other artifacts with that degree of mechanical sophistication have come from the 14th century or later.
Stais uncovered the mechanism while exploring the Anitkythera shipwreck off the northwest coast of Crete. Divers discovered the sunken ship in 1900 and had already unearthed statues, musical instruments, and other artifacts. Stais guessed that the mechanism was a clock and other archaeologists conjectured it was some type of astronomical device. But the mechanism, which has between 30 and 70 very small gears, underwent years of cleaning and it wasn’t until British science historian Derek J. de Solla Price began to investigate it in earnest that archaeologists realized the significance of the artifact, which had a front dial that showed the progress of the sun and moon through the zodiac; an upper rear dial showing various monthlong and yearlong cycles; and a lower rear dial that tracked the progress of a single month with an adjoining dial that tracked the 12 months of the lunar year.
Today the mechanism is on display at the National Archaeological Museum of Athens and is studied by the Antikythera Mechanism Research Project. In 2008, the Project found the inscription “Olympia” on the mechanism, and they now think the device may have been used, in part, to track the occurrence of the ancient Olympic games.
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