What ancient device, found in a 1901 shipwreck, is called the world’s oldest known analogue computer?

The Antikythera mechanism is the ancient device found in a 1901 shipwreck and often called the world’s oldest known analogue computer. The wreck was discovered near the Greek island of Antikythera, and the corroded bronze object was later recognized as a sophisticated system of gears.

Research indicates that the mechanism was made in the second or early first century BCE. Its dials could model astronomical cycles, including the position of the Sun and Moon and the timing of eclipses. A spiral dial also represented the Metonic cycle, a period of 19 solar years that is approximately equal to 235 lunar months.

The mechanism reveals that ancient Greek craftsmen could combine precise gear design with mathematical astronomy. Many fragments survive, but the original device is incomplete, so scholars reconstruct its functions from inscriptions, gears, and imaging studies.

It is not a modern computer and did not use electricity. The label “analogue computer” refers to its ability to represent changing astronomical quantities mechanically. The Nebra Sky Disc is older, but it is not a geared calculating machine.