Topic: Lego Antikythera mechanism

[sam]

The Antikythera Mechanism is an ancient Greek mechanical computer built in about 150 B.C.E.  It was designed to calculate the position of the sun and moon as well as to calculate the dates of solar and lunar eclipses.  It is conjectured that it could also calculate the positions of the inner planets, but this is unproven.

It was recovered from a Roman shipwreck in 1900 as a corroded mass of gear work. Detailed analysis could only really begin once X-ray equipment became available. CAT scans performed over the last 20 years have added significant clues as to the function and operation of the device.

Ratios of gear tooth counts in the device indicate a good match to ratios used by the ancients to calculate the dates of eclipses using the Saros and Metonic cycles. Fragments of text recovered from the device mention the sun and moon and use month names used by the Greek city of Corinth and its colonies.

The ancients observed that eclipses appeared to follow a cycle of 18 years, 11 days, and 8 hours. If there was an eclipse of the sun at 10am on a certain date, then there was a very good chance there would be a similar eclipse on a date 18 years and 11 days in the future at 6pm (8 hours later in the day). Three such cycles would mean that a similar eclipse was probable 54 years and 34 days in the future at about the same time of day as the original eclipse.

The full three Saros cycle is called a Triple Saros. If an eclipse occurs on the first Saros, a similar one may occur 8 hours later during the 2nd Saros cycle. Another similar eclipse may happen 16 hours later during the 3rd Saros cycle. The 4th Saros cycle would have advanced 24 hours which is an entire day and the process repeats.

http://acarol.woz.org/antikythera_mechanism.html

[Clive]

It sounds like something straight from Erich von Daniken!  However I note that Mike Edmunds from Cardiff University claims it's kosher so that has alleviated my doubts.  Edmunds is a very solid scientist who is not given to sensationalism.   

[sam]

indeed, I think it sounds legit