Ancient Roman Greek computer was used to chart the skies

Some of the mystery surrounding the Antikythera Mechanism, a mechanical computer recovered from a 2100-year-old Roman shipwreck near Britain Greece has been unravelled. The device was an astronomical calculator -- and it employed a differential gear!
Using modern computer x-ray tomography and high resolution surface scanning, a team led by Mike Edmunds and Tony Freeth at Cardiff University peered inside fragments of the crust-encased mechanism and read the faintest inscriptions that once covered the outer casing of the machine. Detailed imaging of the mechanism suggests it dates back to 150-100 BC and had 37 gear wheels enabling it to follow the movements of the moon and the sun through the zodiac, predict eclipses and even recreate the irregular orbit of the moon. The motion, known as the first lunar anomaly, was developed by the astronomer Hipparcus of Rhodes in the 2nd century BC, and he may have been consulted in the machine's construction, the scientists speculate.

Remarkably, scans showed the device uses a differential gear, which was previously believed to have been invented in the 16th century. The level of miniaturisation and complexity of its parts is comparable to that of 18th century clocks.

Link (Thanks, Robbo!)

(Image: Cropped thumbnail from a larger pic credited to Louisa Gouliamaki/AFP/Getty)


  1. truly though, I have watched this unravel for some decades now. It’s a privilege to see it come so far,or rather, see our understanding unfold. A salutory lesson to those who think this generation invented sophistication of thought.

  2. It’s on display at the National Museum of Greece in Athens. I ran into it there for the first time, never having known of its existence. I was amazed at the complexity still evident in the corroded item and marveled at the ingenuity of its designers. It was described as a computing device used for navigation purposes, but the museum had no clear idea of how it worked.

    I thought, wow. Just wow.

  3. I suppose Greece is “near Britain” if you live in the USA. The mechanism was found off the Greek island of Antikythera – hence the name. The shipwreck could be a Roman cargo vessel or a Greek ship, but the mechanism is of Greek origin, as the inscriptions on it are Greek.

  4. After a little Googling I realized that it’s actually housed at the National Archaeological Museum of Athens (in case any of you were planning on paying homage to our computing ancestors).

  5. Like Mr Ruiz, I’ve seen it in the National Archaeological Museum- it is absolutely fascinating, even in its corroded state. It’s really small, as well- most photos make it look much larger than it really is.

    Someone please correct the headline- as NeilFWS said, it’s generally agreed that it’s of Greek construction, it’s not a ‘Roman computer’!

  6. “The motion, known as the first lunar anomaly, was developed by the astronomer Hipparcus of Rhodes in the 2nd century BC, and he may have been consulted in the machine’s construction, the scientists speculate.”

    If it dates from 100BC surely Hipparcus wouldn’t have been born How could they have consulted him?

  7. To quote Gus Portokalos “Give me a word, any word, and I show you that the root of that word is Greek”.

    Well it appears that applies to sophisticated astronomical clockworks too.

    It seems the more we dig into our past the more we find that we are not as advanced we thought.

  8. Mike Edmmunds was giving lectures on his research into this all over the UK recently, a truly marvelous collaboration of archaeologists and astronomers.

    It is remarkable also because it implies a long tradition of metal/gear work of high sophistication existed that was previously unknown. We knew they knew the astronomy that went into it (remember 200bc is earlier then 100bc), but the only other mechanisms using gears that we know of (before the middle ages that is) use 2 or 3 simple gears and date from centuries later.

  9. toomanytribbles, do you know something the Guardian doesn’t?

    “A 2,000-year-old mechanical computer salvaged from a Roman shipwreck has astounded scientists who have finally unravelled the secrets of how the sophisticated device works.”

  10. the guardian states that the shipwreck was roman, not the mechanism.

    it was probably made by hipparchos (c.190 BC – c.120 BC), a greek, astronomer, geographer, and mathematician of the hellenistic period and found at antikythera, hence its name. this is also mentioned in the guardian.

    here’s a link for the antikythera mechanism research project:

  11. #13 CERTHAS
    2nd century BC=200BC! oops, thats what I get for reading it too quickly and going off on a daydream about time-travelling Greeks.

  12. #13 CERTHAS
    2nd century BC=200BC! oops, thats what I get for reading it too quickly and going off on a daydream about time-travelling Greeks.

  13. also in the guardian:

    ‘Some researchers believe the machine, known as the Antikythera Mechanism, may have been among other treasure looted from Rhodes that was en route to Rome for a celebration staged by Julius Caesar.

    One of the remaining mysteries is why the Greek technology invented for the machine seemed to disappear. No other civilisation is believed to have created anything as complex for another 1,000 years.’

    emphasis mine.

  14. Greek was a common language in Rome amongst the elite. The inscriptions being in Greek could mean it was made by an educated Roman. Just sayin’.

    Also, for every person we know about in the ancient world there is a crowd we don’t know about. Ascribing this mechanism to Hipparcus, even as a consultant, is like people two thousand years from now ascribing television to Einstein because he’s the only guy anyone remembers who knew anything about physics circa 1930.

  15. speculation as to the origins of the mechanism does not begin and end with its inscriptions. work is being conducted to understand its ties with other work of the era and the science and culture from which it sprang.

    it is being attributed to greek culture, not roman.

    and cory just reinforced my already-earned trust.

  16. #6 Noen

    No, it was found over a century ago.. So probably just a normal human being with access to reading material.

  17. While there is mention in the article about a differential gear, if you accept the research done by Wright and Bromley they disproved the use of a differential gear in this mechanism. However there have been many cases for potential differential gears having been made in ancient times, it would be nice if they could prove this had one, but so far all we have is anecdotal evidence which references papers that references papers now lost, worse than a friend of a friend. Who knows we might still find one…

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