2,000 year-old Astronomical Gadget Linked to Greek Games
An international team of scientists lead by Cardiff University in Wales has cracked a 2,000 year-old mystery: the purpose of the Antikythera clock found at the site of a Roman shipwreck off the Greek island Antikythera. Professor Mike Edmunds of the School of Physics and Astronomy and mathematician Dr. Tony Freeth have published their findings in the July 31 Nature issue. Using technology provided by Hewlett Packard (US) and X-Tek Systems (UK), they found evidence that the Antikythera device mapped the four-year cycle of the Olympics as well as the cycles of other Greek games.
The Antikythera device was already known to predict solar and lunar eclipses, and the movement of the planets through intricate calculations. Sponge divers in 1902 found the device split into 82 pieces composed of bronze gears and teeth, encrusted dials and inscriptions. An X-ray machine provided by X-Tek Systems called "Bladerunner" helped solve the puzzle. The machine gives three-dimensional X-rays, using the latest "microfocus" X-ray techniques, allowing researchers to view inscriptions and gearing at a resolution better than a tenth of a millimeter. This is truly a phenomenal feat because inscriptions that have not been visible for two thousand years can now be read.
The discovery of the inscription "NEMEA" on one of the dials was the first hint that the device might be related to the Greek games. Such an inscription is representative of the Nemean games, which was part of the Olympic cycle. Freeth and other scientists then deciphered the words "ISTHMIA" for the games at Corinth, "PYTHIA" for the games at Delphi, and "OLYMIA" for the Olympic games. In addition, a 19 month calendar was inscribed on the back of the device.
"The interpretation of the upper-back dial as a [calendar] is not new, but the authors have for the first time been able to recover all month names from the few heavily damaged remaining fragments of the 235 original labels," noted Francois Charlotte, independent researcher and scientific manuscript cataloguer at the Chester Beatty Library in Dublin, Ireland.
The Greek astronomer Geminos described such a calendar system, but these findings provide the first concrete evidence of its existence. Geminos described a system in which months have 30 days with one day omitted every 64th day in order to have the correct average month length over a cycle of 19 years.
"Historians of astronomy had until now only doubted that this scheme had been actually used in civil life. But the evidence from the Antikythera mechanism now proves them wrong," said Charlotte.
The names of the months are similar to those used in Corinth, suggesting that the device may have been built in Syracuse, Sicily, the then Corinthian colony where Archimedes had lived. Despite being built several decades after Archimede's death, the device may be linked to one of Archimedes' inventions.
The findings support the theory that nothing as complex as the Antikythera mechanism was invented until 1000 years after its creation.
Professor Edmunds commented, "It does raise the question what else were they making at the time."
The researchers' next goal is to create a computer model demonstrating how the machine actually worked, and then a working replica.
Written by: Brittany Raffa
Edited by: Falishia Sloan
Published by: Hoi See Tsao