Antikythera mechanism
A geared astronomical calculator recovered from a Greek shipwreck. It encoded eclipses, the planets and the Games — fourteen centuries before Europe's clocks.
- Location
- Greece · Europe
- Civilisation
- Hellenistic Greece
- Period
- ~−150
- Technique
- Calculator with ~30 bronze gears
- Studies
real support, not settled. A revisable snapshot of the state of research, never a judgement.
→ Show on the mapThe elements of the site
Where the site is
35.870° N, 23.300° E · satellite view
What science says
3D CT tomography (Freeth et al., Nature 2006): the mechanism calculated the ecliptic positions of the Sun, the Moon and the five visible planets, lunar phases, the Metonic calendar (19 years / 235 months), eclipses via the Saros cycle (223 synodic months), heliacal risings/settings, and the cycle of the Panhellenic Games — the function is largely understood.
The Hellenistic mechanical tradition (Ctesibius, Philo of Byzantium; Cicero reports that Archimedes built a planetarium) shows that the know-how existed — but no precursor of comparable complexity has ever been found.
Several functional reconstructions exist, both hand-built and 3D-printed.
The Saros cycle (223 synodic months ≈ 18 years 11 days) is encoded in a 4-turn spiral divided into 223 cells on the back face — each cell indicates the probability and type of eclipse (solar or lunar). This mechanism derives from Babylonian astronomy, not Greek trigonometry.
What remains unexplained
Echoes across time
Modeling the sky with gears: the Antikythera gesture resurfaces in the analog machines of the 20th century.
Freeth et al., Nature (2006) · history of computation
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