A Greek sponge-diver was in for the shock of his life that day in October 1900. As he dived deep off the coast of the small Greek island of Antikythera, he spotted what looked like decaying corpses of horses and people.

In fact, they were statues lying in the hull of a ship that sank around 70 BC. Despite the wealth of cultural treasures in the ship, one small object is worth more than all the rest put together: the wooden and bronze device that became known as the Antikythera Mechanism (fragments shown below).

Archaeologists have worked out that the ship had stopped in Rhodes, an island that had been the home of Hipparchus, a leading astronomer of ancient times. It seemed a good bet that Hipparchus, or one of his pupils, had invented a device that would show, in a practical way, the celestial motions that Hipparchus was calculating.

But, in July 2008, Alexander Jones – a New York historian – discovered that the writing on the Mechanism showed that it didn't come from Rhodes, but probably from Sicily. And that had been the home of the greatest mathematician and engineer of the ancient world: Archimedes.

Archimedes (left) is most famous, today, for rushing down the street naked, shouting "Eureka", when he discovered his law of flotation. He also experimented with levers and with gears.

Interestingly, the Roman writer Cicero described another of the great Greek geek’s inventions: "Archimedes fastened on a globe the movements of Moon, Sun and five wandering stars [which] made one revolution of the sphere control several movements utterly unlike in slowness and speed."

Think of the "globe" as a circular dial, and this is an almost exact description of the later Antikythera Mechanism. It suggests Archimedes was the godfather of the world's first astronomical computer.

And what if someone had carried on Archimedes' astonishing lead in computing? In the late twentieth century, it would have led me far beyond the computer in Cambridge that was showing me the deaths of stars - at a distance.

As the great guru - and fan of the Antikythera Mechanism - Arthur C. Clarke once put it: "if the insights of the Greeks had matched their ingenuity, the Industrial Revolution might have begun a thousand years before Columbus. By this time, we would not merely be pottering around the Moon; we would have reached the nearer stars..."

For more information

The Antikythera Mechanism Research Project
http://www.antikythera-mechanism.gr/

Jo Marchant's book on the Antikythera Mechanism
Decoding the Heavens