Mar 16, 2021 I Paul Seaburn

Scientists Model the Secret Gears of the Ancient Antikythera Mechanism

In 1901, divers looking for sponges off the coast of the Greek island of Antikythera shot holes through the idea that computers are a modern invention with the discovery of a 2,000-year-old Roman-era shipwreck containing a puzzling machine that was eventually identified as a sophisticated astronomical calculator that became known as the Antikythera Mechanism. Engineers quickly identified it as the world’s first known analog computer, but missing pieces and the lack of an owner’s manual frustrated attempts to recreate the Antikythera Mechanism … until now.

“Solving this complex 3D puzzle reveals a creation of genius—combining cycles from Babylonian astronomy, mathematics from Plato’s Academy and ancient Greek astronomical theories.”

University College London (UCL) researchers are obviously excited about their 3D model, explained in their new study published in the journal Scientific Reports. Led by UCL Professor Tony Freeth, the team started with the 82 fragments recovered from the shipwreck, which over the years have been partially identified as pieces of complex gears. In 2006, Freeth used surface imaging and high-resolution X-ray tomography on once-hidden surfaces to find inscriptions that are parts of a user’s guide to the mechanism. Unfortunately, any recreation of the Antikythera Mechanism was stymied by the lack of any parts from the front display. Undeterred, Freeth believed the rest of the parts could help.


“For example, there are certain features in the surviving bits—holes and pillars and things like that—which people have said: ‘well, we'll just ignore that in our explanation. There must be a use for that but we don't know what it is so we’ll just ignore it.’ Effectively, what we've done is we've not ignored anything. So the enigmatic pillars and holes, all of a sudden, now make sense in our solution. It all comes together and it fits the inscriptional evidence.”

In simple terms, the team looked at the back and figured out what was screwed into it from the front. The 2006 inscriptions helped, as did another in found in 2016 which revealed that the front cover included a pair of values, 462 years and 442 years. According to Vice, the works of the pre-Socratic philosopher Parmenides linked these numbers to Venus and Saturn – specifically, they are the planets’ synodic periods respectively – the time it takes for the planets to return to the same position in the sky. The researchers then factored in the belief of astronomers at the time that Earth was the center of solar system and reverse-engineered a system of gears to that would match the calculations. All that was left was to recreate a front panel with holes for clock-like arms – one for each of the five known (at that time) planets – that would move around a picture of the sky as a handle on the side was turned. Oh, and one more twist from Adam Wojcik, a materials scientist at UCL and a co-author of the study:

“If you're going to show all the planets, you're going to have to get all their positions correct. As you rotate the handle on the side of the mechanism, all these little planets start to move around like clockwork in this kind of mini-planetarium and occasionally, one of them will turn backwards, and then it would move forwards again, and then another one, further out, will start to turn backwards.”

That’s right – the Antikythera Mechanism was able to duplicate the illusion of the planets moving backwards in the sky in relation to the Earth! Pretty impressive for ancient Greeks. Or is it? Wojcik knows what you’re thinking.

“Unless it's from outer space, we have to find a way in which the Greeks could have made it. That's the next stage and the exciting bit is, I think that’s the final piece of the jigsaw.”

Did the beings who some believe helped build the Egyptian pyramids make a stop in Greece before heading home? Ponder that while you check out the excellent photos of what the sponge divers found and what the researchers modeled – the beautiful bronze and mysterious Antikythera Mechanism.

Paul Seaburn
Paul Seaburn is the editor at Mysterious Universe and its most prolific writer. He’s written for TV shows such as "The Tonight Show", "Politically Incorrect" and an award-winning children’s program. He's been published in “The New York Times" and "Huffington Post” and has co-authored numerous collections of trivia, puzzles and humor. His “What in the World!” podcast is a fun look at the latest weird and paranormal news, strange sports stories and odd trivia. Paul likes to add a bit of humor to each MU post he crafts. After all, the mysterious doesn't always have to be serious.

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