A turn-on date for the mysterious device?
Discovered by sponge divers on a Roman-era shipwreck off the Greek island of Antikythera in 1901 as a chunk of barnacle encrusted bronze, what is now known as the Antikythera Mechanism is one of the most startling archæological discoveries ever made (see FT250:51-53, 327:56-57, 410:3435). Although crushed, corroded and incomplete, the mechanism has been reconstructed by archæologists to reveal what has been called the world’s first computer, manufactured up to 200 years before Christ, using knowledge and techniques that no one had suspected existed before the 14th century, when astronomical clocks first appeared. In its original form it would have been a shoeboxsized device with precisionmade bronze cogs and dials covered in tiny inscriptions. When in operation it would have been able to predict eclipses and other astronomical events as well as tracking the four-year cycle of athletic contests that took place in the ancient world.
Many questions about the device still remain, such as who made it, when and where? How do the various elements actually fit together, and is there more to be found in the wreck? Some researchers believe it originated in Syracuse in Sicily, where Archimedes lived, and so could have been created by him, while others believe it came from Pergamon, located in what is now Turkey. One thing that might help identify its origin is working out the date from which the mechanism started its calculations. Now, a group of archæologists have published a proposed “turn on” date for the mechanism on the online preprint database arXiv, where research can be posted prior to peer review.
The archæologists have come up with a start date for the mechanism of 22 December 178 BC. They believe this is the most likely date as there was a solar eclipse over the Mediterranean lasting more than 12 minutes that day, and the following day,
They have come up with a start date of 22 December 178 BC
23 December, was the Winter Solstice. Further contributing to the significance of the day were the phases of the Moon, starting on 22 December, and that the Isia festival in honour of the Egyptian goddess Isis was being celebrated in both Egypt and Greece at that time. The researchers believe this confluence of events was a “very rare coincidence” that created a memorable date to work out the machine’s calculations from. Aristeidis Voulgaris, the lead author of the paper and team leader of the Functional Reconstruction of Antikythera Mechanism –The FRAMe Project – says that the starting date would need to be “very characteristic, important and easily detected”, and believed it was also likely that the date was within the lifetime of the maker, who would have noted the coincidence of events and chosen them as the basis for the device’s calculations.
“Usually, in order to perform time calculations, it is more common to select a date from the recent past rather than one in the future,” he said.
Not all archæologists agree with Voulgaris’s start date, or his reasoning. Alexander Jones, a professor of the History of the Exact Sciences in Antiquity at New York University’s Institute for the Study of the Ancient World, dismissed his findings, saying: “It’s not a paper that would withstand competent peer-review… There are a lot of problems with it, ranging from major issues to minor ones that nevertheless are symptomatic of lack of good grounding in the broad context of ancient astronomy and science.” He points to what he sees as a glaring error: the date proposed would mean that Kraneios, a season associated with wine making, whose dates are predicted by the mechanism, would fall in February each year which, Jones points out, is “not a particularly good month for ripe grapes”. He backs the date proposed in two 2014 papers, which set the start date at 12 May 204 BC and ran through 223 lunar months, beginning and ending with a lunar eclipse. livescience.com, 14 Apr 2022.