The Antikythera mechanism

The claim

"A bronze gear computer from ancient Greece is too advanced to be human."

Where the idea comes from

Found by sponge divers in a Roman-era shipwreck in 1901; its complexity surprised historians for decades.

What the evidence shows

1. It is a hand-cranked calculator of the positions of the sun and moon, the moon's phases, eclipses and probably the planets, with at least 30 surviving bronze gears.
2. CT scans (2005 onwards) revealed thousands of tiny inscriptions, a user's manual in Greek, using Greek astronomical cycles such as the Metonic and Saros cycles.
3. Its models match Greek astronomy of the time, including its approximations. An alien-made device would not copy human errors.
4. Ancient writers including Cicero describe similar devices made by Archimedes and Posidonius.

What is still open

Researchers are still reconstructing the missing planetary gearing. It shows Greek engineering was more advanced than we once thought.

Our verdict

Explained A masterpiece by Greek engineers, carrying Greek astronomy and Greek text.

Sources

• A model of the Cosmos in the Antikythera mechanism (Scientific Reports, 2021)
• Antikythera mechanism (Wikipedia)

Checked 31 October 2026. Spotted a newer source? Tell us.