Edison, NJ
Dimitrios Kondos was stuck on the Greek island of Antikythera. During Easter of 1900, Captain Kondos and his crew of sponge divers were en route to North Africa and stopped at Anthikythera to wait for the strong winds to pass. In the meantime, the team spent time diving off of the coast of the island. One of the divers, Elias Stadiatis, dived to a depth of 45 meters, or 148 feet, and promptly rose to the surface to report a disturbing finding: amongst the rocks on the seafloor were heaps of rotting skeletons and horses. Believing that Stadiatis was experiencing narcosis and hallucinating, Kondos dove to the same depth, only to surface with the arm of a bronze statue.
At the end of April of the same year, the men returned to Antikythera after leaving for North Africa and notified the Hellenic Navy of the wreck. By June of 1901, numerous bronze statues were recovered, as well as an estimated 39 marble statues and a lyre. Pieces of the ship and smaller artifacts were also recovered before the project was shut down after numerous divers suffered the effects of decompression sickness. In May of 1902, a Greek archaeologist named Valerios Stais discovered something unprecedented: a corroded piece of bronze that was recovered from the shipwreck not had only readable inscriptions in Greek, but a gear, indicating it was a part of a larger machine. This machine later became known as the Antikythera Mechanism.
The machine was estimated to have been built around 200 BC and was discovered in several different fragments, some of which were bigger than others. The fragments were made of bronze, and according to the estimates of archaeologists, the entire machine would be as big as a shoebox. Inscriptions found on the machine fragments were written in Greek and described the purpose of the device and the mechanics of the machine, which are described below.
A hand-turned shaft would be connected to a crown gear, which is a gear designed similar to a crown, which would be connected to the main gear which would, in turn, be connected to further gears. Each full rotation of the main gear would correspond to one solar year. A large dial would be on the front of the machine with pointers that showed the positions of the Sun and the Moon relative to the zodiac, or the division of the year by months, and a silver ball that displayed the different phases of the moon.
On the back of the machine, two large dials were placed. The large upper dial would have five slots, along with a moving pointer that shows the 235 synodic months of the lunar cycle. The 235 synodic months, also known as the synodic period, is the amount of time that it takes for something in the solar system, whether it be a planet or an asteroid, to return to the same position. The lunar cycle, or the Metonic cycle, is 19 years long and has the important purpose of regulating our calendars. A smaller dial also indicated time, but in gaps of four years to show when games like the ancient Olympic games should occur. The second large dial had a spiral with symbols inscribed to show different months where there was a likelihood of a solar or lunar eclipse, all based on the saros cycle, which was an interval of time lasting 18 years and 11 days, after which the solar and lunar eclipses will resume. Based on the inscriptions on the machine, it was determined that there was a display of the positions of the planets on the front of the machine, but the actual display has not been found.
A common misconception is that the ancient world was not very technologically advanced; however, ancient civilizations built ways to track the position of planets, the Sun, and the Moon, as well as lunar phases and eclipses. Even though 122 years have passed since the discovery of the shipwreck off the coast of Antikythera, we have learned so much about the technology of the ancient Greeks and even more about the first analog computer in the world. Despite these feats, we still have to learn more about these technologies if we wish to understand more about the ancient world. As of now, archaeologists still do not fully understand how the ancient Greeks managed to build a mechanism that, by today’s standards, would seem impossible without spacecraft or complex mathematics. By understanding and learning more about the machine, we can learn more about the tech geniuses that roamed the Earth before us.
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