In 1901 divers found a lump of corroded bronze in a shipwreck off the island of Antikythera. Inside were dozens of precise gears. It could predict eclipses and track the planets, more than 2,000 years ago.
Truth label: Established. Strong evidence and broad agreement among experts.
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Nothing like it for a thousand years
Gearing this complex does not appear again in the historical record until medieval astronomical clocks.
It ran on a hand crank
Turn the handle and dials showed the date, the phase of the moon and upcoming eclipses.
It even tracked the Olympics
One small dial counted down the four-year cycle of the Panhellenic games.
Learn
- What survives. 82 fragments and around 30 surviving bronze gears, the largest about 13 cm across.
- How it worked. Interlocking gears turned in ratios matching known astronomical cycles that Babylonian astronomers had recorded.
- Why it matters. It shows ancient technical skill was far more advanced than surviving objects usually suggest.
Test yourself
Where was the mechanism found?
In a shipwreck. Sponge divers found it in a Roman-era wreck in 1901.
What could it predict?
Eclipses. Its gears modelled the cycles of the sun and moon.
Sources
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