Before modern computers were a dot on the technology map, there was the Antikythera mechanism which is said to be the first analogue computer found in a shipwreck near Greece in 1900. It was found at the turn of the 20th century by a group of fishermen. In 1902, a Greek politician Spirydon Stais had commissioned an underwater excavation, where between the coins, sculptures and pottery was a rusted lump of metal which turned out to be the ancient computer Antikythera Mechanism.
It is believed that the device was used to analyse the positions of celestial bodies using a complex series of bronze gears. What’s fascinating about the device is it was created some 100 years before the birth of Christ and before mankind had any kind of understanding about astronomy and physics. We are talking even before Galileo and Isaac Newton were born.
Antikythera’s user interface is deceptively simple, operated by a simple knob on the side. This conceals the intricacy within, amounting to a complex mathematical model, tracking the movements of planetary bodies and incorporating a series of sub-mechanisms to account for the eccentricities of their rotation.
A dial on the faceplace featured the Greek zodiac and an Egyptian calendar; pointers showed the location of the moon and the five planets known at the time. On the machine’s back, an upper dial shows a 19-year calendar (matching the solunar cycle) and the timing of upcoming Olympic games. A lower dial shows a 76-year cycle (when the Olympic and solunar cycles coincide) and indicates the months in which lunar and solar eclipses can be expected.
For the past several decades, scientists have been using CT scans and X-rays to look inside the mechanism and reconstruct it to understand what it might have looked like during 200 and 70 BCE. A complex clockwork mechanism composed of 30 meshing bronze gears, a team led by Mike Edmunds and Tony Freeth from Cardiff University used X-ray tomography to peer inside the ragments of the crust-encased mechanism to read the faintest inscriptions that covered the outer casing of the machine and detailed imaging revealed that it has 37 gear wheels which enabled it to follow the movements of the moon and the sun through the zodiac to predict eclipses, and even model the irregular orbit of the moon. Some believe that the 2nd century BC astronomer Hipparchus of Rhodes may have had a hand in the machine’s construction.
The ship carrying the device also contained vases in the Rhodian style, leading some to deduce that it was constructed at an academy founded by Stoic philosopher Posidonius on that Greek island. At the time, Rhodes was a busy trading port in antiquity and a centre of astronomy and mechanical engineering and hoem to Hipparchus. The mechanism uses Hipparchus’s theory for the motion of the moon, which suggests the possibility that he may have designed it or at least worked on it.