Ancient computer showed Olympics cycle

A 2,100-year-old bronze-and-iron astronomical computer that predicted eclipses and other astronomical events also showed the cycle of the Greek Olympics and the related games that led up to it, researchers will report today.

The research team has also deciphered all the month names from the corroded fragments of the “Antikythera” mechanism, providing the first concrete evidence that an astronomical scheme devised by the Greek astronomer Geminos was put to practical use.

Teasing out the month names was “a really spectacular achievement,” said science historian Francois Charette of the Ludwig Maximilians University in Munich, Germany, who was not involved in the research. Historians “had until now doubted that this scheme had actually been used in civil life, but the evidence from the Antikythera mechanism now proves them wrong,” he said.

The inclusion of the data on the Olympic Games on what is now called the Olympiad Dial of the clock-like mechanism surprised researchers because the dates of the ancient Olympics, held every fourth summer from 776 B.C. to A.D. 393, would have been well known to all, just as the time of the modern Olympics is now.

“The inclusion of the Olympiad Dial says more about the cultural importance of the games than about their advanced technology,” said Tony Freeth of Images First Ltd. in London, a member of the research team that will report the results in the journal Nature.

The Antikythera mechanism, so named because it was found in 1901 in a Roman shipwreck off the Greek island of Antikythera, is thought to have been made about 100 B.C.

Its purpose was a mystery for over 100 years, but in 2006, researchers used a massive X-ray tomography machine – similar to what is used to perform CT scans on humans – to examine the fragments.

They concluded the device originally had 37 gears that formed an astronomical computer. Two dials on the front show the zodiac and a calendar of the days of the year that can be adjusted for leap years. Metal pointers show the positions in the zodiac of the sun, moon and five planets known in antiquity. Two spiral dials on the back show the cycles of the moon and predict eclipses.