The Antikythera Mechanism was retrieved from a Roman shipwreck off the Greek island of Antikythera in 1901.

The Antikythera mechanism is a marvel.

ONCE in a blue moon - no, wait, it needs to be longer than that - something truly astonishing is discovered. Yes, I mean more astonishing than discovering Nicole Kidman once dated a guy who wasn't shorter than her.

In the world of astronomy, such a thing is the Antikythera mechanism.

Antikythera is an insignificant small Greek island in the Aegean Sea. In 1900, sponge divers discovered a shipwreck there dating back to the 1st century BC. Aside from the artefacts you would expect to recover from a trading vessel of the period, there was also a small, enigmatic box that turned out to be an extraordinary find, inspiring one noted scholar to claim it more valuable than the Mona Lisa.

Because of its fragile condition and our inability to see inside it at that time, this mechanical conundrum was put on the backburner as perhaps an anachronism that was way too complex to have been created by ancient Greeks. However, beginning in the 1950s, much investigation has gone into deciphering its secrets. In fact, the latest studies show the level of miniaturisation of intricate gears within was on a par with 19th-century clocks.

It now appears this device performed many tasks. Composed of 30 gears and a number of faces and dials, it stakes a claim to being the first analog computer. Its internal construction and movements are based on astronomical and mathematical theories developed by Greek astronomers of the Hellenistic period. It's thought to be possibly connected to Archimedes and his teachings because the inscriptions of the months on its face are those used in Corinth and its colonies, where he lived, and he was known for designing innovative machines.

With the use of modern, non-invasive methods to determine its interior structure, we came to understand it could predict the positions of the known planets, sun and moon, much like a modern planetarium. Furthermore, it could be used as a calendar with compensation for the extra quarter day of the solar year. As well as having a spherical model of the moon that could show its current phase, it could also forecast eclipses and simulate the anomaly in the moon's angular velocity.

Brilliant - but there's more. It indicated which years were to feature the Olympic Games, the Panhellenic Games and others. All this and more spell out an amazing genius, producing clockwork mechanisms way before we had the first clocks.