That’s the title of a new, freely accessible scholarly paper on the Antikythera mechanism you can find here. Here’s the abstract:

The Antikythera Mechanism is a fragmentarily preserved Hellenistic astronomical machine with bronze gearwheels, made about the second century B.C. In 2005, new data were gathered leading to considerably enhanced knowledge of its functions and the inscriptions on its exterior. However, much of the front of the instrument has remained uncertain due to loss of evidence. We report progress in reading a passage of one inscription that appears to describe the front of the Mechanism as a representation of a Greek geocentric cosmology, portraying the stars, Sun, Moon, and all five planets known in antiquity. Complementing this, we propose a new mechanical reconstruction of planetary gearwork in the Mechanism, incorporating an economical design closely analogous to the previously identified lunar anomaly mechanism, and accounting for much unresolved physical evidence.

For all those ancient aliens enthusiasts out there, please note the line about the five planets known in antiquity. The Gadarene rush among some in of that ilk to label the mechanism as proof of high (read: alien) technology in the ancient world would of course be proven wrong by this analysis. We’d have another case (just like Sumerian and Babylonian astrolabes and astronomical texts, contra Zecharia Sitchin) where the “aliens” presumably behind this technology only knew about five planets in our solar system.

Amazing how consistent that is. Why? Because we’re talking about human naked eye astronomy, not alien knowledge.