Photo shows fragments of the Antikythera Mechanism
, left, have now been examined with the latest in high-resolution imaging systems and three-dimensional X-ray tomography.
The Antikythera Mechanism Project
In 1901 divers working off the isle of Antikythera found the remains of a clocklike mechanism 2,000 years old. The mechanism now appears to have been a device for calculating the motions of stars and planets by Derek J. de Solla Price [ From June 1959 Scientific American p.60-7 ] Historians of science concluded that this was an instrument that calculated and illustrated astronomical information, particularly phases of the Moon and planetary motions, in the second century B.C.
The Antikythera Mechanism, sometimes called the world's first computer, has now been examined with the latest in high-resolution imaging systems and three-dimensional X-ray tomography. A team of British, Greek and American researchers was able to decipher many inscriptions and reconstruct the gear functions, revealing, they said, "an unexpected degree of technical sophistication for the period."
The researchers, led by Tony Freeth and Mike G. Edmunds, both of the University of Cardiff, Wales, are reporting the results of their study in Thursday's issue of the journal Nature.
They said their findings showed that the inscriptions related to lunar-solar motions and the gears were a mechanical representation of the irregularities of the Moon's orbital course across the sky, as theorized by the astronomer Hipparchos. They established the date of the mechanism at 150-100 B.C.
In Australia, clockmaker Frank Percival made a model based on the research done by Allan Bromley and Michael Wright, who subsequently developed his own model.
With the new results and the latest gearing diagram from the Antikythera Mechanism Research Project, new models are being built by other researchers, with some being working models. The results of the AMRP have been integrated into at least three models, made by Michael Wright, Dionysios Kriaris, Massimo Vicentini and Tatjana van Vark, while the Research Group is developing a model based on the ongoing research.
During September 2005, three specialized scientists from Hewlett-Packard's Mobile and Media Systems Laboratory came to Athens with their innovative digital imaging system to examine the surface inscriptions and other features on the Antikythera Mechanism. The HP team, Tom Malzbender, Dan Gelb and Bill Ambrisco-brought with them a remarkable piece of specialist equipment: a Dome that surrounds the sample under examination and takes a series of still photos to analyze the three-dimensional structure of the surface. This enables astonishingly detailed examination of fine details such as faded and worn inscriptions. It has been a revelation for the research team.
During October 2005, another team of specialists from the cutting-edge company, X-Tek Systems, came to Athens. Led by the company's pioneering proprietor, Roger Hadland, the group of experts consisted of David Bate, Andrew Ramsey, Martin Allen, Alan Crawley and Peter Hockley. Their aim was to use the very latest x-ray technology to look at the internal structure of the mechanism with its complex and confusing gear trains. With them they brought the prototype of a very powerful new x-ray machine, the eight-tonne "Bladerunner". Originally designed to search for minute cracks in turbine blades, this machine gives astonishingly detailed three-dimensional x-rays, using the latest "microfocus" x-ray techniques. It has opened a remarkable window on microscopic internal details of inscriptions and gearing at a resolution better than a tenth of a millimeter. Inscriptions can now be read that have not been seen for more than two thousand years and this is helping to build a comprehensive picture of the functions of the Antikythera Mechanism.
Who made the Mechanism?
Once again there is no hard evidence identifying a particular maker. It is thought by some that it was probably made by someone of the Hipparchos school. Hipparchos (c.190 BC - c.120 BC) was a Greek, astronomer, geographer, and mathematician of the Hellenistic period. Hipparchos was probably born in Nicaea (now Iznik, Turkey), and probably died on the island of Rhodes. He is known to have been a working astronomer at least from 147 BC to 127 BC. Hipparchos is considered the greatest astronomical observer and, by some, the greatest overall astronomer of antiquity. He was the first Greek to develop quantitative and accurate models for the motion of the Sun and Moon. For this he made use of the observations and knowledge accumulated over centuries by the Ancient Babylonians. Amongst the many works of Hipparchos, is his development of a quantitative geometrical model for the first anomaly of the Moon's motion. It has been recently shown by the Antikythera Mechanism Research Project that the Antikythera Mechanism includes an ingenious mechanical realization of this model. Furthermore, Hipparchos is credited with the invention or improvement of several astronomical instruments, which were used for a long time for naked-eye observations. As such it is very tempting to associate Hipparchos as the maker of the Mechanism, especially as he was contemporaneous with date of manufacture of the Mechanism (150 to 100 BC).