Ancient computer reveals Greek legacy through lunar tracking

The Antikythera Mechanism is an approximately 2,200-year-old analog computer created in ancient Greece. Made of bronze and consisting of complex systems of gears, it was used to calculate the positions of celestial bodies and predict astronomical events. It still holds many unsolved mysteries. Recently, researchers discovered that the computer tracked the Greek lunar calendar, contrary to previous beliefs that it followed the ancient Egyptian calendar.

Divers found the Antikythera Mechanism in 1901 off the coast of the Greek island of Antikythera. They discovered it on an ancient merchant ship at 138 feet. The divers recovered numerous statues, and the device is now considered the world's oldest computer. In 1902, archaeologist Valerios Stais determined that the mechanism contained 37 bronze gears, ranging from 0.4 inches to 6.7 inches in diameter. These gears were driven by a hand crank on the side, which moved several pointers.

Initially, researchers thought it was an ancient clock, but it became a much more advanced device. About the size of a shoebox, the Antikythera Mechanism was used to observe the movements of the Sun, Moon, and planets, synchronize the solar calendar with the lunar calendar, and predict solar and lunar eclipses. At first, experts believed that the mechanism tracked the solar clock used by the Egyptians, but the latest research indicates it followed the Greek lunar calendar, reports Live Science.

In 2020, a team led by independent researcher Chris Budiselic used new X-ray images, measurements, and mathematical analysis to determine that the mechanism likely did not cover a full solar year but 354 days, as in the lunar calendar. Further research, published on June 27th of this year in "The Horological Journal" by a team from the University of Glasgow, confirmed these findings.

In the latest analyses of the Antikythera Mechanism, statistical techniques developed for the Laser Interferometer Gravitational-Wave Observatory (LIGO) to detect gravitational waves were employed. These methods allowed for identifying the number and distribution of missing holes in the calendar ring. It was ultimately determined that the mechanism likely had 354 or 355 holes, indicating that it tracked the lunar calendar used in ancient Greece.

"The results from the Glasgow team provide new evidence that one of the components of the Antikythera Mechanism most likely served to track the Greek lunar year," the researchers stated in a release. Graham Woan, co-author of the study, emphasized the precision of the holes, which required very accurate measuring techniques and a remarkably steady hand.