The Antikythera Cosmos ― Experts Recreate A Mechanical Cosmos For The World's First Analog Computer

Scientists have long struggled to solve the so-called Antikythera mechanism's gearing system — a remarkable and baffling astronomical calculator perhaps the earliest example of a gearing device.

It was first discovered in the Roman-era shipwreck by Greek sponge divers in 1901 and was identified on 17 May 1902 by archaeologist Valerios Stais. Once filled with gears and used to predict the heavenly bodies' movements, the fragments of a shoebox-sized contraption have baffled and astounded generations of researchers since then.

It wasn't until the second half of the 20th century; researchers realized that it was dated to ancient Greece – probably around 100BC-200BC – and that it accurately traced the sun and the moon's movements, predicting eclipses and other astronomical events. 

It could also be used to track the four-year cycle of athletic games similar to the Olympic cycle of the Ancient Olympic Games.

The mechanism has been described as an astronomical calculator as well as the world's first analog computer. It's made of bronze and includes dozens of gears.

The device's back cover features the cosmos display description, which shows the five planets' motion (Mercury, Venus, Mars, Jupiter, and Saturn) known when the device was built.

But only a third of the device survived, leaving researchers to consider how it worked and what it looked like.

Previous studies have resolved the back of the mechanism, but the nature of its complex front gearing system remains a mystery.

It is a complex clockwork mechanism composed of at least 30 bronze mesh gears. No other machine of such complexity has ever been found.

X-ray Computed tomography (X-ray CT) decoded the structure of the rear of the machine in 2005, but the front of the machine remained largely unsolved. The X-ray CT also revealed inscriptions describing the Sun's motion, the Moon, and all five planets known in antiquity.

But, now, University College London (UCL) researchers have come up with a computational model that reveals a dazzling display of the ancient Greek cosmos, according to a new paper published in the journal Scientific Reports. 

Researchers believe that they have solved the mystery – at least in part – and that they have set out to reconstruct the device, the gear wheels, and everything else to test whether their proposal works. If they can build a full-scale replica of the Antikythera using modern machinery, they aim to do the same with ancient techniques.