The Antikythera Mechanism is an ancient shoebox-sized device that is sometimes called the world’s oldest computer for its ability to perform astronomical calculations.
Discovered by sponge divers off the Greek island of Antikythera in 1901, the remains of the mechanism are now housed in the National Archaeological Museum of Athens. Only 82 fragments, made up of about a third of the original mechanism, survive today, researchers wrote in a 2021 study published in the journal Scientific reports (opens in a new tab). It was built around 2,200 years ago.
What was the Antikythera Mechanism doing?
The mechanism was able to perform different calculations, and it could help track the movements of the Sun, moon and five of the planets; it could even indicate when sports competitions, such as the Olympics, were due to take place, the researchers wrote. “It was a bronze-geared mechanical computer that used revolutionary technology to make astronomical predictions, mechanizing astronomical cycles and theories,” the team wrote in the journal article.
Since the discovery of the Antikythera mechanism, researchers have tried to understand the device. And although they have made considerable progress, many questions remain unanswered. For example, researchers still don’t know who did it. Some scholars have postulated that the Greek inventor Archimedes (287 BC to 212 BC) was the creator of the mechanism, but this is uncertain. The inscriptions on the mechanism are written in Greek.
Whoever made the device should have known a lot about astronomy, metallurgy and mechanology, Aristeidis Voulgaris, team leader of the Functional Reconstruction of the Antikythera Mechanism (Frame) project, told Live Science in an email. This project aims to reconstruct what the mechanism originally looked like and to better understand it. They would also have needed “great manual dexterity”, he noted.
Fragments recovered from the mechanism contained writing and inscriptions, and over the past two decades scientists have been able to read more. Greek inscriptions using high-tech imaging methods, such as 3D x-ray scanning. This allowed them to learn more about how the mechanism works.
CT scans “revealed inscriptions describing the movements of the sun, moon and five known planets in antiquity and how they were displayed in front like an ancient Greek cosmos,” the researchers wrote in the Scientific Reports article. . The mechanism used “cycles from Babylonian astronomy, math of Plato’s Academy and ancient Greek astronomical theories,” the researchers wrote.
The mechanism represents “a level of technology surpassing anything else of the kind for which we have physical remains or detailed descriptions from antiquity,” Alexander Jones, professor of the history of exact sciences in antiquity at the Institute for the New York University Study. of the ancient world, wrote in his book “A Portable Cosmos: Revealing the Antikythera Mechanism, Scientific Wonder of the Ancient World (opens in a new tab)(Oxford University Press, 2017).
What did the Antikythera Mechanism look like?
The authors of the Scientific Reports article discovered that someone looking at the front of the mechanism would have seen dials indicating the movements of the moon, the sun, the lunar nodes (points where the moon’s orbit intersects the ecliptic, the path the sun seems to take through the constellations), Mercury, VenusMarch, Jupiter and Saturnas well as the Zodiac calendar.
The back of the mechanism had dials indicating the Metonic cycle (a 19-year cycle after which the the phases of the moon occur on the same days of the year), the Callippic cycle (a period of 76 years, equal to four Metonic cycles), the Olympiad cycle (when the Olympic Games were held every four years), the Saros cycle (a period of more than 18 years between lunar eclipses) and the exeligmos (a period of more than 54 years, i.e. three cycles of Saros).
Between the front and rear of the mechanism were a huge array of gears, designed so that all dials represented the correct timing of all cycles.
“Suppose a user of the Antikythera Mechanism wants to check the eclipse forecast for a particular month a few years ahead. The user winds the mechanism up to the desired date as shown on one of his calendars,” said Tony Freeth, researcher at the Antikythera Mechanism. Research Project, written in a 2014 article published in the journal PLOS A (opens in a new tab).
Wreckage of the Antikythera Mechanism
Although the ship that contained the Antikythera Mechanism was discovered over a century ago, the wreckage has not been fully excavated. The size of the ship that carried it is unclear, and the distance at which the artifacts are scattered is also somewhat uncertain. Its location and depth make it difficult to dig, according to Woods Hole Oceanographic Institute (opens in a new tab) (WHOI). The site is at an angle on the seafloor about 130 to 165 feet (40 to 50 m) below the surface, which means it is too deep for divers to dig for long but too shallow to be surveyed by remote-controlled vehicles, according to the WHOI. .
Despite these difficulties, a new excavation program is being carried out by a team of archaeologists and new artefacts continue to be found, shedding light on what the ship, which probably sank around 65 BC, looked like. bronze arm which was once attached to a statue, a board game, possible remains of a ancient throneand one marble statue head of HerculesLive Science previously reported.
Researchers noted that many artifacts were luxuries for the wealthy. So far, recent excavations have not unearthed any new remains of the mechanism.
In 2016, archaeologists unearthed the ancient skeleton of a man during the sinking, Live Science reported at the time. Recently, scientists have tried to extract DNA to learn more about the man.
Researchers still don’t know why the mechanism was on the ship in the first place. “It was not an object that one would casually subject to the risk of travel,” Jones wrote in his book. While the mechanism may not have been a one-of-a-kind device, it certainly would have been something of considerable value. One possibility is that a technician was transporting the device to its intended owner, Jones wrote, noting that a storm likely sank the ship, taking the mechanism with it. The origin and destination of the ship are the subject of ongoing research and debate among scholars.
The “start date” of the Antikythera Mechanism
Scholars still debate the accuracy of the Antikythera Mechanism”start date“, the earliest date on which all calculations made on the mechanism are based. Research published in March 2022 on the preprint server arXiv (opens in a new tab) proposed December 22, 178 BC as the start date of the mechanism. The researchers noted that on this day there was a lunar eclipse, followed by the winter solstice, followed by a feast dedicated to the goddess Isis. While Isis was an Egyptian goddess, she was highly regarded in Greece at that time.
However, other (opens in a new tab) university teams have (opens in a new tab) proposed May 12, 204 BC as the most likely start date, noting that on this day a lunar eclipse would have been visible in Greece, and that this date is closer to Archimedes’ lifetime. It is possible that he or someone working in his workshop built this device.
Freeth, T. et al. (2021) “A Model of the Cosmos in the Ancient Greek Antikythera Mechanism” Scientific Reports 5821
https://doi.org/10.1038/s41598-021-84310-w (opens in a new tab)
Freeth, T. (2014) “Eclipse Prediction on the Ancient Greek Astronomical Calculating Machine Known as the Antikythera Mechanism” PlosOne
https://doi.org/10.1371/journal.pone.0103275 (opens in a new tab)
Jones, A. (2017) “A Portable Cosmos: Revealing the Antikythera Mechanism, Scientific Wonder of the Ancient World” Oxford University Press
Voulgaris, A. et al (2022) “The initial calibration date of the Antikythera mechanism after the mechanical spiral apokatastasis of Saros” arXiv
https://arxiv.org/abs/2203.15045 (opens in a new tab)
Originally posted on Live Science.