How did an ancient Greek device predict eclipses with astronomical precision?

The answer

The Antikythera mechanism, built around 150–100 BCE, included a sophisticated eclipse prediction system based on the Saros cycle - a period of approximately 18 years, 11 days, and 8 hours after which nearly identical eclipses recur. The device's Saros dial, located on its rear face, tracked 223 lunar months and could predict both solar and lunar eclipses, including their time of day and color characteristics. A 2021 University College London study published in Scientific Reports created the first complete computational model of the device's front panel, revealing it tracked the variable motions of the Moon using an epicyclic gear system - a mechanical implementation of Hipparchus' lunar theory. This represents a level of astronomical and engineering sophistication not matched until the medieval Islamic astronomical tradition.