Антикитера механизмы: ежелгі астрономиялық есептегіш

Ancient analogue astronomical computer

The Antikythera mechanism (,/æ//n//t//ɪ/'/k//ɪ//θ//ɪər//ə/ ANtihKIHtherə) is an Ancient Greek hand powered orrery (model of the Solar System), described as the oldest known example of an analogue computer used to predict astronomical positions and eclipses decades in advance. This artefact was among wreckage retrieved from a shipwreck off the coast of the Greek island Antikythera in 1901. as containing a gear. The device, housed in the remains of a wooden framed case of (uncertain) overall size , to demonstrate how it may have looked and worked. In 2005, a team from Cardiff University used computer x ray tomography and high resolution scanning to image inside fragments of the crust encased mechanism and read the faintest inscriptions that once covered the outer casing. This suggests it had 37 meshing bronze gears enabling it to follow the movements of the Moon and the Sun through the zodiac, to predict eclipses and to model the irregular orbit of the Moon, where the Moon's velocity is higher in its perigee than in its apogee. This motion was studied in the 2nd century BC by astronomer Hipparchus of Rhodes, and he may have been consulted in the machine's construction. between 150 and 100 BC, It must have been constructed before the shipwreck, which has been dated by multiple lines of evidence to approximately 70–60 BC. In 2022 researchers proposed its initial calibration date, not construction date, could have been 23 December 178 BC. Other experts propose 204 BC as a more likely calibration date. Machines with similar complexity did not appear again until the astronomical clocks of Richard of Wallingford in the 14th century. This wreck of a Roman cargo ship was found at a depth of off Point Glyphadia on the Greek island of Antikythera. The team retrieved numerous large objects, including bronze and marble statues, pottery, unique glassware, jewellery, coins, and the mechanism. The mechanism was retrieved from the wreckage in 1901, probably July. It is unknown how the mechanism came to be on the cargo ship. All of the items retrieved from the wreckage were transferred to the National Museum of Archaeology in Athens for storage and analysis. The mechanism appeared to be a lump of corroded bronze and wood; it went unnoticed for two years, while museum staff worked on piecing together more obvious treasures, such as the statues. On 17 May 1902, archaeologist Valerios Stais found one of the pieces of rock had a gear wheel embedded in it. He initially believed that it was an astronomical clock, but most scholars considered the device to be prochronistic, too complex to have been constructed during the same period as the other pieces that had been discovered. German philosopher Albert Rehm became interested in the device; he was the first to propose that it was an astronomical calculator. Investigations into the object lapsed until British science historian and Yale University professor Derek J. de Solla Price became interested in 1951. In 1971, Price and Greek nuclear physicist Charalampos Karakalos made X ray and gamma ray images of the 82 fragments. Price published a paper on their findings in 1974. Also found was a bronze disc, embellished with the image of a bull. The disc has four "ears" which have holes in them, and it was thought it may have been part of the Antikythera mechanism, as a "cog wheel". There appears to be little evidence that it was part of the mechanism; it is more likely the disc was a bronze decoration on a piece of furniture.

Investigations by Freeth and Jones reveal their simulated mechanism is inaccurate. The Mars pointer is up to 38° wrong in some instances (these inaccuracies occur at the nodal points of Mars' retrograde motion, and the error recedes at other locations in the orbit). This is not due to inaccuracies in gearing ratios in the mechanism, but inadequacies in the Greek theory of planetary movements. The accuracy could not have been improved until c. 160 AD when Ptolemy published his Almagest (particularly by adding the concept of the equant to his theory), then much later by the introduction of Kepler's laws of planetary motion in 1609 and 1619. While the device may have struggled with inaccuracies, due to the triangular teeth being hand made, the calculations used and technology implemented to create the elliptical paths of the planets and retrograde motion of the Moon and Mars, by using a clockwork type gear train with the addition of a pin and slot epicyclic mechanism, predated that of the first known clocks found in antiquity in Medieval Europe, by more than 1000 years. Archimedes' development of the approximate value of pi and his theory of centres of gravity, along with the steps he made towards developing the calculus, suggest the Greeks had enough mathematical knowledge beyond that of Babylonian algebra, to model the elliptical nature of planetary motion. Of special delight to physicists, the Moon mechanism uses a special train of bronze gears, two of them linked with a slightly offset axis, to indicate the position and phase of the moon. As is known today from Kepler's laws of planetary motion, the moon travels at different speeds as it orbits the Earth, and this speed differential is modelled by the Antikythera Mechanism, even though the Ancient Greeks were not aware of the actual elliptical shape of the orbit.

The level of refinement of the mechanism indicates that the device was not unique, and possibly required expertise built over several generations.

Several exhibitions have been staged worldwide, and at the Musée des Arts et Métiers in Paris. The National Geographic documentary series Naked Science dedicated an episode to the Antikythera Mechanism entitled "Star Clock BC" that aired on 20 January 2011. The YouTube channel Clickspring documents the creation of an Antikythera mechanism replica using the tools, techniques of machining and metallurgy, and materials that would have been available in ancient Greece, along with investigations into the possible technologies of the era. The film Indiana Jones and the Dial of Destiny (2023) features a plot around a fictionalized version of the mechanism (also referred to as Archimedes' Dial, the titular Dial of Destiny). In the film, the device was built by Archimedes as a temporal mapping system, and sought by a former Nazi scientist as a way to travel back in time and help Germany win World War II. On February 08th of, 2024, a 10X scale replica of the mechanism was built, installed, and inaugurated at the University of Sonora in Hermosillo, Sonora, Mexico. With the name of Monumental Antikythera Mechanism for Hermosillo (MAMH), Dr. Alfonso performed the inauguration. Durazo Montaño, Governor of Sonora and Dr. Maria Rita Plancarte Martinez, Chancellor of the Universidad de Sonora. The Ambassador of Greece, Mr. Nikolaos Koutrokois, and a delegation from the Embassy.