Tuesday, January 02 2007 @ 11:59 pm EST
Contributed by: Jay_Hilgartner
"Science and the technical wonders it produces CAN blaze suddenly towards the heavens and then just as quickly return to the desert sands, lost and forgotten."
|The Antikythera Device, a computer from ancient times recently determined to be an accurate mechanism for determining the movements of the Sun, Moon and five known planets of the ancient world. Source: Wikipedia, taken from APOD for December 5, 2006.|
One of the quiet but great stories of 2006 was the confirmation that a lump of corroded metal retrieved more than a century ago from the Aegean Sea was in fact an extremely ingenious ancient computer revealing a computational sophistication unmatched until the fourteenth century. In an article in the November issue of Nature,
a panel of scientists and classical scholars led by Michael Edmunds released their findings on the Antikythera Mechanism, named after its place of discovery in A.D. 1900 in a Roman shipwreck. Said Edmunds, "Before its sojourn on the sea bed, (the Antikythera Mechanism) computed and displayed the movement of the Sun, the Moon and possibly the planets around Earth, and predicted the dates of future eclipses. It’s one of the most stunning artifacts we have from classical antiquity."
The Mechanism, enclosed within a wooden case a little bit smaller than a shoebox, contains at least 30 gear wheels, each one handcut from a single sheet of bronze, and ranging in size from nearly the width of the case to less than a centimeter across. On the front and sides are a number of dials and windows showing the zodiac, the day of the year, the phases of the moon, and the positions of the sun, moon and five planets known at the time. On the back are two spiral dials--one showing the 235 month Metonic cycle
, which correlates the orbit of the moon around the earth with the earth's orbit around the sun, and the other the 223 month Saros cycle
, used to predict ecllipses.
We even have the names of who could have built this technological wonder. The wrecked ship that the Mechanism was on could be dated to sometime in the first century B.C. and probably from the Greek islands of Rhodes and Cos. On the device itself was a dial to compensate for errors in the Egyptian calendar which was used at that time. This dial was adjusted in such a way that researchers were able to determine an exact date - 80 B.C. - when the Mechanism was last set. Classical scholars also know that just seven years earlier, in 87 B.C., a Greek named Geminus wrote a book which describes a device that sounds remarkably like the Antikythera Mechanism.
|Jay Hilgartner sits at a computer station in today's modern Library of Alexandria where he recently visited. The new library is built on the site of the ancient Library of Alexandria, where detailed plans for building a device such as "The Antikethera Mechanism" may have been kept. All photos by the author unless otherwise noted. Click HERE for interior of library, and HERE for exterior.|
Perhaps it was built by Geminus himself or by another astronomer mentioned by him - Poseidonius of Rhodes. Poseidonius is also mentioned by Cicero as the designer of an instrument which records the movement of the Sun, Moon, and the five planets. Or, others say, it may have been designed centuries earlier by the brilliant Archimedes or by another Rhodes’ astronomer Hipparchus, who died around 120 B.C.
Suffice it to say that the sophistication of the Antikythera Mechanism gives all lovers of science and civilization pause, for it challenges the idea of continued uninterrupted human progress. Science and the technical wonders it produces CAN blaze suddenly towards the heavens and then just as quickly return to the desert sands, lost and forgotten. Indeed, the Hellenistic world that the Mechanism was created in did just that.
The great city of Alexandria in Egypt, the center of Hellenistic culture, once boasted a library and museum containing over half a million books, attracting scholars from all the known world. It was the first deliberately built great research center, museum, and library all in one, lavishly supported by the first three Ptolemy pharaohs. The library flourished for almost 300 years until it was burned in 48 B.C. during Julius Caesar’s war with Pompey. Many books were lost, but many also survived in a branch library in Alexandria at a temple complex called the Serapeum. With the Roman conquest, Alexandria’s golden age had passed but scholars still regarded the city as the place to complete their studies, that is, until the fourth century A.D. when the Serapeum was destroyed by an angry Christian mob. The books were either burned or lost in time. It is sobering to think that a scroll describing how to construct the Antikythera Mechanism may have been destroyed either in the library’s first fire or in the destruction of the Serapeum.
Click read more for the rest of this fascinating story.