An Ancient Orrery — The Beautiful Mystery of the Antikythera Mechanism

Photo by Laura Ockel on Unsplash

In 1900, sponge divers stopped off the Greek island of Antikythera. They were waiting for favorable winds to cross to their fishing grounds off North Africa.

The bored divers decided to gear up and do practice dives while waiting. Elias Stadiatis went down to 45 meters and then signaled retrieval.

He had found something. He told them he had found bodies. Lots of bodies. They thought he was nitrogen-drunk.

Dimitrios Kondos, the Captain, geared up and went to take a look and quickly realized that Stadiatis was quite sober.

Stadiatis had found an ancient shipwreck. Kondos came up with a single artifact, a bronze arm, to demonstrate the find, marked the location on a chart and they went fishing. On their way back, they did a second dive to get more to show the authorities. Who promptly hired them to finish the job.

The Antikythera shipwreck was excavated through 1901, but efforts stopped after a diver died.

In 1902, Valerios Stais was looking through the hastily-retrieved artifacts (this was 1900, after all) and found something amazing. It was severely-corroded bronze, but it was a gear.

The shipwreck dated from the 1st century AD.

Gears were not something they expected to find.

Stais had found the famous Antikythera Mechanism, fragments of which were put together.

He had, to be precise, discovered the oldest known computer.

What was the Antikythera Mechanism?

Stais came to a very logical conclusion about his find. Clearly, something with a gear and inscriptions was a clock. Or possibly an astrolabe, used for ship navigation.

It was about the size of a mantle clock and there are indications it was contained in a wooden case. But it would take a while before we were able to really put it back together.

In 1974, Derek de Solla Price published the first really good interpretation of the mechanism, and he argued that it was, in fact, a calendar computer…a device for plotting dates through the past and the future. It took X-ray imaging to determine this, and continued work demonstrated that it was an orrery.

(Von Daniken being Von Daniken said it had to be made by aliens. I mean, the ancient Greeks couldn’t, right?)

In 2006, CT scans were published of the fragments, and attention came back to the old orrery/astronomical clock.

These scans showed that it was probably similar in many ways to Medieval astronomical clocks. It was a clock with at least seven hands, which displayed celestial time. The sun, the moon, the five visible planets. It also showed the phases of the moon.

It was hand operated, that is to say the operator would have had to move things on a crank. So, it was not an astronomical clock, even if it probably looked like one.

It was an orrery, a device designed to demonstrate the motions of the heaven, and the idea of it being a “calendar clock” is not without merit. It showed, amongst other things, the optimum date to start the Olympic games.

But the theory I like is that it was a device used to teach students of astronomy about how the solar system, in their eyes, worked.

Who Made It?

The other mystery about the Antikythera mechanism is who made it.

Not space aliens, sorry von Daniken. (Can we please stop with the space aliens as a way to demonstrate that Past People Weren’t Smart?)

But there’s some evidence that might point in a specific direction. The month names were Corinthian, not Athenian. The dial that shows the Olympics also shows two regional athletic festivals, Naa, which was held in northwest Greece and Halieia, which was held on Rhodes.

There’s also written historical evidence of such mechanisms. Cicero talked about how Archimedes made an orrery much earlier. And Cicero also specifically said that there was a guy on Rhodes, named Posidonius, who was making “models of the heavens.”

So it’s quite possible that the Antikythera Mechanism was made in the workshop of Posidonius, some time in the first century, for a customer in northwest Greece. Said customer was probably an astronomer or natural philosopher who needed it to teach his students.

Of course, this is all speculation, but the Antikythera Mechanism’s mystery, while not solved, is definitely much less mysterious than it was in the past.

There were probably a number such devices that we haven’t found because they weren’t shipwrecked.

Freelance writer, freelance editor, novelist and short story writer. Jack of many trades.

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