The Antikythera Mechanism: A new approach towards lost gear teeth, scales and displays of the upper back dial consistent with the chronological and geographical context of its construction

Kostas Kotsanas

Graduate Mechanical Engineer

PhD candidate, University of Patras

According to evidence, the Antikythera mechanism was built in the second half of the 2nd century B.C. and was the product of a Rhodian or Asia Minor workshop. The upper part of the mechanism's back dial was devoted to the calculation of the lunisolar year with a spiral of 235 lunar months (based on the 19-year Metonic cycle), whereas on the inside there is a circular arrangement for the timing of six "crown" games (stephanites) - four Panhellenic and 2 local - one of which has not yet been identified yet (M. Right and the International Antikythera Mechanism research project team: T. Freeth, X. Moussas, I. Seiradakis, Bitsakis, et al.). Inside the spiral, the 76-year Callippic cycle is proposed to be adapted to symmetrically mirror the cycle of athletic competitions to adjust the Metonic cycle. In addition, there are already two proposals for the 7 intercalary months of the Metonic lunar calendar: the Eukleius (T. Freeth) and the Machaneus (M. Anastasiou).The present paper attemps a different approach in this field towards the mechanism's lost gear teeth, scales and displays, consistent with the chronological and geographical context of its construction and the already established findings. Specifically, the following data are investigated and reviewed: a) research on the local crown games that have not been deciphered yet b) research on the 7 intercalary months of the Metonic calendar in relation to the time scale of crown games and c) research and calculation of the arrangement for maximum accuracy of the lunisolar calendar. This new approach provides for the modern world an additional insight towards the concepts of science and technology in ancient Greece.