In April of 1900, a cadre of Greek sponge divers (literally divers who collect sponges off the sea bed) located a shipwreck off the coast of the Greek island of Antikythera (anti-kith-era). When the first diver whipped off his helmet and babbled about having found treasure, the world did not know just how impressive the find was. Dozens of statues, adornments, objects, jars, pots and whatnot were brought up. Artifacts from over 2,000 years before, dating back to somewhere around 140 BCE. Among the finds were some of the most impressively preserved bronze statues from the era.
The Antikythera philosopher and the Antikythera youth. Bronze sculptures of exceptional quality and craftsmanship.
Two years later, when the excitement had died down a bit, curators began to work with the less impressive finds from the Antikythera shipwreck. Among the doodads and chunks of pots that they parsed through was a blob of wood and bronze, previously unnoticed because of how prosaic it was. While checking over the artifacts, archaeologist Valerios Stais noticed that there was a gear squashed into the metal. His first assumption was that the thing was some sort of astrological clock, built by the Greeks millenia before Enlightenment Europeans even tried to puzzle together a clockwork. Historians and archaeologists largely ignored the claims of Stais, arguing that a geared mechanism would be far beyond the capacity of ancient people, even the Greeks.
This is the main gear, it has over 200 fine teeth and served a specific purpose. For some perspective, when this thing was made, Caesar was still around. The Antikythera device was Thousands of years ahead of its time.
The mechanism was relatively forgotten until the 1950s, when an Archaeologist and a Nuclear Physicist worked together and X-ray’d the entire bronze piece, finding several more layers of gears and inscriptions underneath the outer corrosion. The device was recreated in the flurry of research that followed the find. Inventors found that the mechanism was likely used to tell time on an astrological scale. Spinning one of the nobs would cause the device to whir to life and would show you the relative positions of the Sun, Mars, Venus, Mercury, Saturn and Jupiter, as well as showing the relative position of stars, the day, and perhaps most importantly, it could predict eclipses far in to the future. The mechanism even had advanced enough mechanics that it could take into account the epicycles of Greek astronomy (Greeks had a Geocentric model of the universe, everything revolved around Earth. If you think that the planets revolve around the Earth, then you have to come up with a really creative way of explaining positions of the planets. Instead of going with a Heliocentric model, most Europeans agreed upon the idea that planets would orbit Earth all the while making tiny orbits of their own about imaginary centerpoints. The bobbling of the planets in a Geocentric model would more or less align the positions of the planets, but it made the math impressively difficult to do.)
If you have 8 minutes to watch, this video gives a more complete description as well as a more visual model of the mechanism: https://www.youtube.com/watch?v=UpLcnAIpVRA
Epicycles made the math work, but at what cost…
60 years of work has come up with several conclusions: That we don’t know who made the thing; it may have been directly based on a device made by Archimedes, it may have been an original creation by a Greek mathematician. That we really are unsure when it was made; recent findings say 205 BCE, older beliefs say 140 BCE (this is important, it means the math that the mechanism used was either a Greek creation or a Babylonian creation depending on when it was built). That we are fairly sure that there must be other inventions like this one, and that the Greeks were advanced far beyond our wildest dreams in their technical skills. Until we find something else similar to it, the Antikythera mechanism remains the only ancient computer we have ever found. Cicero talks about there being devices like it, planetariums and similar manual automatons, but all we currently know about the impressive computers of the ancient world comes from a small box of bronze, tin, and wood that we scraped off the sea floor.