Sponge divers find the Antikythera wreck

Greek sponge divers found a shipwreck off the island of Antikythera carrying statues and a corroded bronze device. The Antikythera mechanism is now seen as an ancient astronomical calculator.

Context

Sponge divers sheltering from a storm in 1900 found the wreck at around 45 meters depth. Greek authorities then ran one of the earliest large underwater salvage operations, recovering marble and bronze statues, jewelry, pottery and the corroded lump later recognized as the mechanism.

The ship is generally dated to the 1st century BCE, probably carrying luxury goods from the eastern Mediterranean. The mechanism itself is thought to be somewhat older, from roughly the 2nd or 1st century BCE.

The device was recognized as geared machinery in the early 1900s, and in the 20th and 21st centuries X-ray imaging revealed dozens of surviving gears and inscriptions in about 80 fragments. Researchers believe it modeled the motions of the Sun and Moon, tracked calendar cycles and could predict eclipses.

Teams, including international groups working with Greek archaeologists, have returned to the wreck since 2014 and recovered more finds. The mechanism is displayed at the National Archaeological Museum in Athens. How many such devices existed remains unknown.

Its discovery changed views of ancient technology, because geared devices of such complexity were not expected until medieval clockmaking in Europe.