Researchers at UCL have solved a large piece of the puzzle from which the ancient Greek astronomical calculator is known as the Antikythera mechanism, a mechanical device that is manually driven and used to predict astronomical events.
The Antikythera mechanism, known to many as the world’s first analog computer, is the most intricate piece of engineering that has survived from the ancient world. The 2000 year old device was used to predict the positions of the sun, moon and the planets as well as lunar and solar eclipses.
Published in Scientific reports, the paper of the multidisciplinary UCL Antikythera research team unveils a new version of the ancient Greek order of the universe (Cosmos), within a complex leverage system at the forefront of the mechanism.
Lead author Professor Tony Freeth (UCL Mechanical Engineering) explained: “We are the first model that matches all the physical evidence and matches the descriptions in the scientific inscriptions engraved on the Mechanism itself.
“The sun, the moon and the planets are displayed in an impressive dazzling tour of ancient Greek splendor.”
The Antikythera mechanism has caused fascination and intense controversy since its discovery in a Roman era shipwreck in 1901 by Greek sponge divers near the small Mediterranean island of Antikythera.
The astronomical calculator is a bronze device consisting of a complex combination of 30 remaining bronze gears used to predict astronomical events, including eclipses, lunar phases, positions of the planets and even dates of the Olympic Games.
Although much progress has been made over the past century in understanding how it works, studies in 2005 using 3D X-rays and surface imaging have enabled researchers to demonstrate how the mechanism predicts eclipses and the changing motion of moon calculated.
So far, the best efforts of researchers have eluded as a complete understanding of the gear system at the front of the device. Only a third of the mechanism survived and was divided into 82 fragments, creating a challenging challenge for the UCL team.
The largest surviving fragment, known as Fragment A, exhibits features of bearings, pillars and a block. Another, known as Fragment D, contains an unexplained disc, 63-speed gear and plate.
In previous research, X-ray data from 2005 were used to reveal thousands of text characters hidden in the fragments unread for almost 2000 years. Inscriptions on the back cover contain a description of the cosmos exhibit, with the planets moving on rings and indicated by marking beads. It was the exhibit the team worked to reconstruct.
Two critical numbers in the X-rays of the cover, of 462 years and 442 years, accurately represent cycles of Venus and Saturn, respectively. When observed from Earth, the planets’ cycles sometimes reverse their motions towards the stars. Experts need to follow these variable cycles over long periods of time to predict their positions.
“The classical astronomy of the first millennium BC originated in Babylon, but nothing in this astronomy suggested how the ancient Greeks found the highly accurate 462-year cycle for Venus and 442-year cycle for Saturn,” the PhD candidate and the UCL Antikythera research team explained. member Aris Dacanalis.
Using an ancient Greek mathematical method described by the philosopher Parmenides, the UCL team not only explained how the cycles for Venus and Saturn were derived, but also succeeded in restoring the cycles of all the other planets. , where the evidence is lacking.
PhD candidate and team member David Higgon explained: “After considerable difficulty, we were able to match the evidence in fragments A and D with a mechanism for Venus, which forms exactly the 462-year planetary relationship, with the 63-tooth gear which plays an important role. ”
Professor Freeth added: “The team then created innovative mechanisms for all the planets that would calculate the new advanced astronomical cycles and reduce the number of gears throughout the system so that it would fit in the limited spaces available.”
“This is an important theoretical advance on how the cosmos is built into the mechanism,” said co-author, dr. Adam Wojcik (UCL Mechanical Engineering), added. ‘Now we have to prove its feasibility by making it with ancient techniques. A particular challenge is the system of nested tubes that carry the astronomical outputs. ‘
Headline Credit: Gary Todd – Public Domain