El mecanismo de Antikitera es una calculadora mecánica antigua de bronce diseñada para prever la posición del Sol, la Luna, y algunos planetas, permitiendo predecir eclipses. Está cubierto de signos e inscripciones astronómicas en griego antiguo, dialecto corintio-siracusano, y fue descubierto en los restos de un naufragio cerca de la isla griega de Anticitera, entre Citera y Creta, y se estima que data del 87 a. C.
Es uno de los primeros mecanismos de engranajes conocido, y se diseñó para seguir el movimiento de los cuerpos celestes.
De acuerdo con las reconstrucciones realizadas, se trata de un mecanismo que usa engranajes diferenciales, lo cual es sorprendente dado que los primeros casos conocidos hasta su descubrimiento datan del siglo XVI.
De acuerdo con los estudios iniciales llevados a cabo por el historiador Derek J. de Solla Price (1922-1983), el dispositivo era una computadora astronómica capaz de predecir las posiciones del Sol y de la Luna en el zodíaco, aunque estudios posteriores sugieren que el dispositivo era bastante más "inteligente".
El año 2010, el grupo de Tacoma-Quilmes, integrado por James Evans y Alan Thorndike de la Universidad de Puget Sound (Tacoma, Estados Unidos) y Christián C. Carman de la Universidad Nacional de Quilmes (Quilmes, Argentina) ha hecho importantes contribuciones. En primer lugar, ha descifrado cómo el mecanismo reflejaba la anomalía solar. Y, en segundo, propusieron una novedosa forma en que se mostrarían los movimientos planetarios. Según ellos, el mecanismo no mostraría su posición en el zodíaco, sino ciertos eventos importantes para los astrónomos (como el comienzo o fin de una retrogradación, la ocultación, etc).
Sus contribuciones proponen la hipótesis según la cual el sistema de epiciclos y deferentes no surgió como respuesta a una exigencia platónica de circularidad de los astros, basada en su divinidad, sino por una razón mucho más terrestre: simplemente como una solución mecánica a la problemática de reflejar con engranajes las regularidades planetarias conocidas por los babilonios.
🦄💫4° SEM32 WORD PLANEACIÓN PROYECTOS DARUKEL 23-24.docx
La máquina de Antikytera
1. Fragmento “A” del
Mecanismo de Antikythera,
Previamente a su
conservación y restauración.
El Mecanismo
de Antikythera
2. El Mecanismo de
Antikythera
Un computador astronómico análogo
Construido circa 87 a.C.
Perdido circa 76 a.C.
Descubierto en 1901 fuera de la isla de
Antikythera (Αιγιλια)
oficialmente llamada Andikithira; y también
conocida como Cerigotto, Sijiljo, y Stus.
3. El Naufragio
50 metros de largo
Localizado entre 15 y 25 metros fuera de
Punta Glyphadia
A 43 metros de profundidad, 140 pies.
Latitud 35º52’30” Norte
Longitud 23º18’35” Este
British Admiralty Chart No. 1685
4. El Sitio del Descubrimiento
Price, 1974Price, 1974
6. Buceando en el Naufragio
El buceo Scuba se inventó 42 años después
del descubrimiento del naufragio
Tiempo de buceo 9 minutos
4 minutos para el descenso y el ascenso
5 minutos en el fondo
7. Buceo recreacional Scuba
Limites de Profundidad
18 metros para los novicios
30 metros recomendados
40 metros absolutos
(para buceos sin descompresión posterior)
PADI, 1995PADI, 1995
.
8. Los Peligros
Agua helada
Corrientes
Profundidad
A 40 metros de profundidad, el agua ejerce
5 veces la presión atmosférica provocando:
– Narcosis de Nitrógeno: “Rapto de la Profundidad”
– Enfermedad de la Descompresión acelerada
PADI, 1995PADI, 1995
Rice, 1995Rice, 1995
.
9. Los costos Humanos
Diez buzos trabajando en el naufragio
Un buzo accidentalmente muerto
Dos buzos permanentemente incapacitados
10. La Recompensa
Estatuas de Mármol y Bronce
Joyería de Oro
Utensilios y Cubiertos
Anforas
El mecanismo de Anthyquitera
La más compleja pieza de maquinaria científica conocida
de la antiguedad.
24. Referencias
Field, J. V. 1985Field, J. V. 1985
Lewis, M.J.T. 1993Lewis, M.J.T. 1993
PADI, 1990PADI, 1990
Price, 1974Price, 1974
Price, 1959Price, 1959
Rice, 1995Rice, 1995
Field, J.V. (1985) “The early history of mathematical gearing” Endeavour, 198-203
La historia antigua de la matemática de engranajes.
Lewis, M.J.T. (1993) “Gearing in the ancient world” Endeavour, 110-115
(Engranajes en el Mundo Antiguo)
“PADI Open Water Diver Manual” (1995), Santa Ana, CA: McPhersons
(Manual de Buceo acúático PADI) Padi
Price, D. J. de S. (1974) “Gears from the Greeks: the Antikythera mechanism - a calendar
computer from ca. 80BC ” (El mecanismo de Antikitera: un calendario computador del
año 80 a.C.)
Augarten, S. 1984Augarten, S. 1984
Augarten, S. (1984) “Bit by bit: an illustrated history of computers” London:
Allen & Unwin. (Bit a bit: historia ilustrada de los computadores)
Price, D. J. de S. (1959) “An Ancient Greek Computer ” Scientific American, 60-67, 1959.
(Una antigua computadora griega)
Rice, R. S. (1995) “The Antikythera Mechanism: Physical and Intellectual Salvage from
the 1st Century B.C.” http://ccat.sas.upenn.edu/rrice.html. 04/11/1996
Notas del editor
Good Morning:
I would like to thank you all for being here this morning for this talk on the Antikythera mechanism.
You are welcome to interrupt the talk at any time if you have any questions
or if you wish you can save questions to the end of the talk.
The Antikythera Mechanism is an analogue astronomical computer built to
display the position of the sun in the zodiac and the phase and position of the moon and possibly other planets.
Built in 87 B.C. Lost around 76 B.C. in use for 11 years during which time it was repaired on at least two occasions once major repair to one of the four main spokes of the drive wheel and a repair to a single tooth on one of the smaller gears.
From this repair work Price concludes that the device was used and was
therefore functional.
It is the most complex scientific device known from antiquity
It was found on a shipwreck off the island of Antikythera. in 1901 by Greek sponge divers.
This is the discovery site off the island of Antikythera
In the foreground you can see the type of boats used by the divers
during the salvage of the wreck.
The divers who discovered the wreck were on there way home from Tunisia in north Africa to the island of Syme
Antikythera is located between Crete and the Greek mainland
Price considered that the mechanism originated on the island of Rhodes and was on it’s was from there to Rome when the ship carrying it sank off the island of Antikythera.
Possibly having been caught in the same squalls that forced the divers to shelter near the island of Antikythera.
All dives on the wreck were made by the diver simply by holding his breath.
No only did the divers have to hold there breath for 10 minuets ( the duration of this talk) they had to contend with
cold water
currents,
and with fading light due to the depth of water
Price does not state how the diver w was killed or how the two were disabled but it is likely that the divers suffered from decompression sickness which causes death in extreme cases and nerve damage in severe cases.
Given that the divers were forced to make a rapid ascent with no stop for decompression it is not unlikely that divers were slightly or severely bent after each dive.
The coldness of the water would also contribute to the likelihood of becoming bent.
The ship was truly a “treasure ship” carring
gold jewelry,
coins,
wine,
Life sized marble & bronze statues
table ware,
and the most complex piece of scientific equipment to survive from antiquity.
The Ephebe of Antikythera, Held in the National Museum of Athens.
Height 1.94m (life sized) Some believe that this is a statue of Perseus holding up the Medusa’s head, others maintain that is is Paris holding up the apple. This is an original work dating from 340/330 B.C.
The Antikythera youth, a statue of a young man, a god, or a hero who held a spherical object in his right hand (possibly Paris with the apple). One of the most brilliant products of the Peloponnesian bronze sculpture dated 340 B.C.
The Philosopher of Antikythera, Portrait of a bearded, elderly man, perhaps a philosopher of the Hellenistic period Dated 250-200 B.C.
Dimensions:
164 mm Wide
48 mm Deep
Front 206 mm High
Back 326 mm High
Fragment “A” is the largest of the four main fragments and contains most of the mechanism.
The mechanism broke into four main fragments after recovery
This lead to it’s discovery eight months after it’s salvage.
The reason for it breaking apart was due to it’s drying out and the wood which held it together shrinking.
Today wood from ancient shipwrecks is treated with polyethylene glycol
a water soluble wax which preserves the wood and prevents it from shrinking as it dries out.
This technology was not used at the time of the discovery of the ship wreck as it was the first underwater archaeology ever undertaken.
Each fragment was photographed before, during and after cleaning
from which Price had schematic diagrams drawn.
The Front Dial reveals very few details prior to cleaning
Fragment “C” is the only fragment that contains any part of the front dial.
The mechanism consists of over 30 gears all cut by hand from a single bronze sheet 2.0 - 2.3 mm thick 1/8 of a digit.
The device consists of two separate assemblies one on the front plate and the other on the back.
Each was connected to the other by a series of squared axles held in place by wedge and slot devices.
Note the repair to main spoke b
Note the use of a co-axial drive shaft
The Antikythera mechanism was a direct precursor to such devices as this Islamic Astrolabe dating from 1200 A.D.
Each gear in the mechanism was cut by hand with a triangular file to produce teeth of exactly 60 degree equilateral triangles.
This is a gear from a astrolabe built around 800 years after the Antikythera mechanism. The technology required to build the Antikythera mechanism survived until the present day and was a direct precursor to Astrolabes which in turn lead to the clock which is one of the most significant inventions of antiquity.
The bronze sheet from which the mechanism was cut was a good quality bronze with no detectable lead which is unusual for ancient bronzes.
There is no trace of zinc and therefore the metal was defiantly bronze and not brass. It appears that the bronze was not gilded and the small traces of gold contained within it are not unusual for an ancient copper alloy.
This pictures a partial reconstruction of the device
The device displayed the positions of the sun and moon by the 19 year cyclical calendar used in classical Greece.
The most interesting feature of the mechanism is the use of a differential turntable which subtracted the sidereal motions of the sun from that of the moon to produce the synodic month, that is the cycle of the phases of the moon.