The Antikythera Mechanism

Found this on the January 20th, 2013 APOD.

At the beginning of the 20th century, divers off the island of Antikythera came across this clocklike mechanism, which is thought to be at least 2,000 years old, in the wreckage of a cargo ship. The device was very thin and made of bronze. It was mounted in a wooden frame and had more than 2,000 characters inscribed all over it. Though nearly 95 percent of these have been deciphered by experts, there as not been a publication of the full text of the inscription.

Today it is believed that [the Antikythera mechanism] was a kind of mechanical analog computer used to calculate the movements of stars and planets in astronomy. It has been estimated that the antikythera mechanism was built around 87 B.C and was lost in 76 B.C. No one has any idea about why or how it came to be on that ill-fated cargo ship. The ship was Roman though the antikythera mechanism was developed in Greece.  One theory suggests that the reason it came to be on the Roman ship could be because the instrument was among the spoils of war garnered by then Roman emperor Julius Caesar. [From Antikythera Mechanism.com]

There’s something compelling about this image— this large wheel armored in centuries of fouling.  I imagine bygone sailors, cranking the heavens across its display face, while they charge their prow through the watered pitch.  In the back are two dials— one of them tracking a 76-year cycle.  A whole life, demarked by a hand moving through a groove.

Here is a replica at work: