New Dates Calculated for Greece’s Antikythera Mechanism

(Giovanni Dall Orto)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TACOMA, WASHINGTON—The Antikythera Mechanism was timed to begin at 205 B.C., making the clock-like device of bronze gears 50 to 100 years older than previously thought, according to a study conducted by James Evans of the University of Puget Sound and Christián Carman of the University of Quilmes in Argentina. The device, which has been called the world’s oldest computer, was recovered from a shipwreck off the Greek island of Antikythera in 1901. Evans and Carman studied Babylonian records of eclipses, reconstructed by John Steele of Brown University, and eliminated possible start dates based upon astronomical phenomena. The highly complex machine may have been based on Babylonian arithmetical methods, and not Greek trigonometry, which didn’t exist in 205 B.C.

Artifact

(Photo courtesy of Nature Publishing Group/Macmillan)

WHAT IS IT?
A working Lego model of the Antikythera Mechanism

DATE
Finished in May 2010

MATERIAL
Lego Technic

NUMBER OF LEGOS
More than 1,500

ORIGINALLY DISCOVERED
1901, in a shipwreck near the Mediterranean island of Antikythera



The original Antikythera Mechanism
(© Antikythera Mechanism Research Project)

It took Andrew Carol 30 days to build a working model of the Antikythera Mechanism—the ancient Greek world's most sophisticated astrological instrument. The original device, dating to the second century B.C., consists of bronze gears. Carol used Legos.
The choice of medium limited Carol, but it illustrated the elegant simplicity of its inspiration. The Greeks could economically perform the math needed to calculate upcoming solar and lunar eclipses using 30 hand-cut gears with between five and 223 teeth—223 is the number of lunar months between eclipses. The Lego Antikythera does its calculations in a less direct manner, requiring more than 100 prefab gears assembled into several modules, each performing separate bits of math. Then seven differentials—additional gears—reconcile the computations from different modules.
The original Antikythera Mechanism is not only simpler than its Lego counterpart, it's more accurate. Carol's device can predict an eclipse to within 24 hours. The original is precise to within 12, thanks to a clever assembly that causes one of its gears to spin faster at some points in its rotation and slower at others, approximating the elliptical orbit of the moon. "Nothing on this planet was as mechanically complicated as the Antikythera Mechanism until the 1300s," says Carol. "It's a testament to the Greeks' genius."

Source:archaeology.com