Return to Antikythera reveals "Titanic of the ancient world"
A team of archeologists have returned to the remote Greek island of Antikythera where they have used the most sophisticated robot and submarine technology to search for one of the technological wonders of the ancient world.
The Antikythera shipwreck site was found by accident by sponge divers blown off course by a storm in 1900. Diver Elias Stadiatis told his shipmates he had seen corpses beneath the waves - the bodies were found to be a pile of bronze statues from an ancient shipwreck. The sponge divers became part of the world's first large scale underwater archeological expedition. They retrieved a remarkable haul, including a glass bowl and a 1.8 metre statue known as the Antikythera youth - one of the finest bronze figures from the ancient world.
But it took several decades before the most extraordinary find from the wreck was understood. Item 15087 was a lump of bronze about the size of a shoebox. It looked like a mechanical clock and was dubbed the Antikythera Mechanism. Originally believed to be from the first half of the first century BCE, a more recent view dates the mechanism at 205BCE.
In 1958, Yale physicist and historian Derek de Solla Price examined the mechanism for himself. He believed its 30 meshing bronze gears were used to calculate astronomical events, such as solar eclipses, or the next full moon, or the dates of the Olympic Games. In 1974, after an X-ray examination of the mechanism revealed missing gear teeth. Price wrote:
"Nothing like this instrument is preserved elsewhere. Nothing comparable to it is known from any scientific text or literary allusion. On the contrary, from all that we know of science and technology in the Hellenistic Age we should have felt that such a device could not exist.
"It must surely rank as one of the greatest mechanical inventions of all time."
Price argued that such a sophisticated device could not have appeared, fully realised, in a vacuum. But the rest of the world largely ignored his efforts. When he died in 1983, his work on the mechanism was still unfinished.
It was taken up by Michael Wright, a curator of mechanical engineering at London's Science Museum. Wright set about building a working model of mechanism, correcting mistakes Price had made regarding the gearing. His model has pointers for the Sun and the Moon, for the planets, and for every day of the year. The hand-cranked gears were hidden inside a wood box, with a large wooden knob on the site.
Further X-rays of the mechanism taken around 2005 found inscriptions on the dials, including the words "sphere" and "cosmos".
Late last year, scientists returned to Antikythera to re-examine the site, and to look for the mechanism's missing pieces. Expedition equipment includes a robotic submarine from Australia and the Exosuit - described as a wearable submarine - which was used for the first time in the open sea.
While they didn't find any more bits of the mechanism, divers found a giant anchor collar, suggesting the ship was much larger than previously believed and may have carried a cargo of up to 300 tonnes. Expedition leader Brendan Foley of the Woods Hole Oceonographic Institute in the US has described the wreck as "the Titanic of the ancient world".
He hopes to return to the site in the European spring. In the meantime, colleagues in Sydney have been asked to mount a metal detector and sonar to the robotic sub to map objects beneath the seafloor for the first time. We await their next finding with interest.
See also from Cosmos: Robots under water