Publications
Publications by the team of The Functional Reconstruction of Antikythera Mechanism – The FRAMe Project
The new findings from the Antikythera Mechanism Front Plate astronomical Dial and its reconstruction – 2018a
A. Voulgaris, A. Vossinakis, C. Mouratidis.
Archeomatica International, Special Issue 3(8), 6-18. https://ex.geoweb.it/geowebhtml/riviste/geomedia/Archeomatica_Inter_2017.pdf
Abstract
This paper refers to the investigation of the Zodiac scale and the Egyptian calendar of the Antikythera Mechanism front plate, based on the known surviving fragments of the Mechanism, mainly of Fragment C (National Archaeological Museum of Athens, inventory number X.15087). Fragment C is the preserved part of the front plate of Antikythera Mechanism, located in front and above the large gear b1. Until now only a portion and other isolated smaller fragments of the front plate survive.
Conclusions from the functional reconstruction of the Antikythera Mechanism – 2018b
A. Voulgaris, A. Vossinakis, C. Mouratidis.
Journal for the History of Astronomy, 49(2), 216-238. https://journals.sagepub.com/doi/abs/10.1177/0021828618762460
Abstract
After a careful examination of the Antikythera Mechanism computed tomography scans from the Antikythera Mechanism Research Project, we designed and constructed the mechanical parts that are visible on the computed tomography scans. We then reconstructed two functional models of the Antikythera Mechanism, and in this paper, we present the observations and the conclusions drawn from their use. The use of these models helped us to understand how the Mechanism worked and provided answers to questions regarding the presence and the use of some parts.
Ancient Machine Tools for the construction of the Antikythera Mechanism parts – 2019a
A. Voulgaris, A. Vossinakis, C. Mouratidis.
Digital Applications in Archaeology and Cultural Heritage Journal, 13, e00092, June 2019. https://www.sciencedirect.com/science/article/pii/S2212054818300353
Abstract
The present work deals with the study, design, original reconstruction and use of the bow drill of the late archaic period (ca 490 BC), as depicted in two different red figure vases and the vertical lathe depicted on an engraved wall painting of the Petosiris tomb of the Ptolemaic era (300 BC). After the reconstruction of the three ancient tools, during the implementation of the FRAMe Project, their use was thoroughly studied, from which useful conclusions were drawn about the material processing in antiquity, as well as the details of the construction of the Antikythera Mechanism components. Following the new findings detected from the authors’ study of the X-Ray Computed Tomographies from Antikythera Mechanism Research Project, these ancient machine tools can be considered as the progenitors of the Hellenistic period machine tools, which were used for the construction of the mechanical components of the Mechanism.
Simulation and Analysis of Natural Seawater Chemical Reactions on the Antikythera Mechanism – 2019b
A. Voulgaris, A. Vossinakis, C. Mouratidis.
Journal of Coastal Research, 35(5), 959–972.https://bioone.org/journals/Journal-of-Coastal-Research/volume-35/issue-5/JCOASTRES-D-18-00097.1/Simulation-and-Analysis-of-Natural-Seawater-Chemical-Reactions-on-the/10.2112/JCOASTRES-D-18-00097.1.short
Abstract
Chemical reactions with seawater changed the bronze material and the color of the Antikythera Mechanism. The deformation and the displacement of the bronze parts are clearly evident on the visual photographs, on Antikythera Mechanism Research Project (AMRP) X-ray radiographs, and computed tomography (CT) scans as a result of the under seawater material density change and the dehydration of the Mechanism after its removal from the Aegean/Kretan Sea bottom. In present work the first steps of the copper/bronze corrosion under the sea are simulated and presented. The geometric changes and the deformations of the Mechanism parts, which have repercussions on their shape, dimension, and relative position, are analyzed. Studying the visual photographs and the AMRP X-ray CTs of the partially preserved parts, the Functional Reconstruction of Antikythera Mechanism Project team digitally reconstructed and completed some of the lost/destroyed wooden and bronze parts and calculated the dimensions of the plates and the wooden casements of the Antikythera Mechanism ancient prototype.
Renumbering of the Antikythera Mechanism Saros cells, Resulting from the Saros Spiral Mechanical Apokatastasis – 2021
Aristeidis Voulgaris, Christophoros Mouratidis, Andreas Vossinakis and George Bokovos.
Mediterranean Archaeology and Archaeometry Vol. 21(2), 107-128. https://www.maajournal.com/index.php/maa/article/view/529/460
Abstract
After studying the design geometry of the Antikythera Mechanism Saros spiral, new critical geometrical/mechanical characteristics of the Back plate design were detected. The geometrical characteristics related to the symmetry of the Antikythera Mechanism design, are independent to the present irregular deformation of the Mechanism parts and were used as calibration points for the Saros spiral cells positional measurements. The Saros cells numbering, was recalculated using the calibration points position. A correction of minus one to the currently accepted numbering of the Saros cells was applied. Following the new numbering, a new proper position for the (displaced) Saros pointer axis-g, in graphic design environment was calculated. The measurements were tested on a bronze reconstruction of the Back plate, by the authors. This research leads to a new important result that the Saros does not start in a random or arbitrary date but only when a solar eclipse occurs within a month. Additional results were also calculated regarding the symmetry of the eclipse events/sequence. The new Saros cell numbering strongly affects the calculations for the initial starting date of the Saros spiral and the eclipse events scheme of the Antikythera Mechanism.
Assembling the Fragment D on the Antikythera Mechanism: its role and operation in the Draconic gearing – 2022
Aristeidis Voulgaris, Christophoros Mouratidis, Andreas Vossinakis.
Mediterranean Archaeology and Archaeometry, Vol. 22, No 3, (2022), 103-131. https://www.maajournal.com/index.php/maa/article/view/807/726
Abstract
The unplaced Fragment D of the Antikythera Mechanism with an unknown operation was a mystery ever since it was discovered. The gear r1, which was detected in Fragment-D radiographies by C. Karakalos is preserved in excellent condition, but this was not enough to directly relate it to the existing gear trains of the Mechanism. The suggestion that Fragment D could be a part of the hypothetical planet indication gearing is a hypothesis, in contradiction with the AMRP tomographies, and leads to mechanical malfunctions. The analysis of AMRP tomographies of Fragment D and its mechanical characteristics, revealed that it could be part of the Draconic gearing. Currently, the three lunar cycles Synodic, Sidereal and Anomalistic are represented on the Antikythera Mechanism. Although the Draconic cycle was well known during the Mechanism’s era as representing the critical fourth Lunar cycle, it seems that it is missing from the Antikythera Mechanism. The study of Fragment D was supported by our bronze reconstructions of the Fragment D, leading to the reconstruction of the Draconic gearing. These results are very important, because with the use of only one hypothetical/missing gear, the Draconic gearing is revealed on the Antikythera Mechanism. Fragment D(raconic) can be perfectly correlated with the Draconic cycle of the Antikythera Mechanism without mechanical problems and the four lunar cycles appear on the Mechanism. Based on the Draconic pointer, the eclipse events can be calculated and engraved on the Saros spiral cells.
The Initial Calibration Date of the Antikythera Mechanism after the Saros Spiral Mechanical Apokatastasis – 2023a
Aristeidis Voulgaris, Christophoros Mouratidis, Andreas Vossinakis.
Almagest 14(1), 4-39. https://www.brepols.net/products/IS-9782503603452-1
Abstract
This work analyzes the phase correlation of the three lunar cycles and the Exeligmos/(Saros) Cycle, after the study of the chapter “About Exeligmos” in “Introduction to the Phenomena” by Geminus. As Geminus reports, each Exeligmos Cycle began on very specific and rare dates, when the Moon was positioned at the starting points of the three lunar cycles: New Moon (Synodic), at Apogee (Anomalistic), and at the Node (Draconic). The extremely large duration of the Annular Solar eclipse occurred on December 22, 178 BC (Saros series 58) marks the start of the “Prominent Saros Cycle Apokatastasis”. The next day, December 23, 178 BC, the Winter Solstice occurred. During these two neighboring dates, the celebration of the religious festival of Isia started in Egypt and Hellenistic Greece. Based on the analysis of the specific position of the Mechanism’s Parapegma events, December 22/23 178 BC appears as the ideal starting date, i.e. functional and representative, in order to calibrate the initial position of the Mechanism’s pointers.
Reconstructing the Antikythera Mechanism lost eclipse events applying the Draconic gearing – the impact of gear error – 2023b
Aristeidis Voulgaris, Christophoros Mouratidis, Andreas Vossinakis.
Cultural Heritage and Modern Technologies, 1, 1-68. https://aaatec.org/documents/article/va1.pdf
Abstract
We present new observations concerning the procedure for the reconstruction of the lost eclipse events engraved in the Saros spiral cells of the Antikythera Mechanism. For the reconstructed eclipse events we applied the necessary, albeit missing, Draconic gearing of the Antikythera Mechanism [using the Fragment D(raconic) – gear r1], which was probably a part of the Mechanism’s gearing, representing the fourth lunar motion, the Draconic cycle. The Draconic gearing is very critical for the eclipse prediction and defines whether an eclipse will occur. For our research we created a program which presents the phase of the four lunar cycles – including the position of the Draconic pointer relative to the ecliptic limits. After calibrating the program according to the preserved eclipse events, the lost eclipse events of the Saros spiral were calculated and discussed. The procedure for the calculation of the events’ times by using solely the Mechanism based on the pin&slot configuration, is also presented. The eccentricity error of a gear which is preserved on the ancient prototype is analyzed. An experimental setup facilitated the analysis of the mechanical errors of the gears and the study of the motion transmission between gears with triangular teeth. The experimental study of the gears errors revealed the strong impact the Antikythera Mechanism pointers’ position has on the results.
Rare Important Astronomical Εvents during the Isia Feast correlated to the Starting Date of the Antikythēra Mechanism: The Helleno–Roman Isis and her Relation to the Solar Eclipses – 2023c
Aristeidis Voulgaris, Christophoros Mouratidis, Andreas Vossinakis.
Journal of the Hellenic Institute of Egyptology, 6, 2023, 77-100. https://www.jhie.gr/paper.php?p=10996256
Abstract
The initial pointers’ position of the Antikythēra Mechanism (calibration) was based on a specific date, related to a unique coincidence of very important astronomical and religious events. During 22/23 December 178 BC (= 17/18 Hathyr) the four Lunar Cycles were at their beginning position, the Moon and the Sun crossed the zodiac sign of Capricorn signifying the Winter Solstice, the annular solar eclipse with the largest duration occurred and the Isia feast started. The Isia feast is related to the myth of Osiris’s death and its return to life via the help of Isis. In the Helleno–Roman Era, this myth is engaged to the Moon and the Sun. A further analysis of the eclipses’ probability of observation/visibility in the vicinity of Egypt and Middle East, explains why these areas exhibit a high probability for the solar eclipses’ visibility, detectability and therefore, their recording. This advantage led to the development of the ancient Babylonian Solar Astronomy and the Saros Period discovery. The missing Sun and the solar corona appearance during a total solar eclipse could be adopted and worshipped as deities by the authorities and priesthoods at these areas, creating magnificent religious stories and symbols.
The Draconic gearing of the Antikythera Mechanism: Evidence for its Operation – The Mechanical behavior of its Parts – 2024
Aristeidis Voulgaris, Christophoros Mouratidis, Andreas Vossinakis.
Journal of the Hellenic InstitutProceedings of the 3rd International Conference Ancient Greek and Byzantine Technology (Association for Research on Ancient Greek and Byzantine Technology)e of Egyptology, 6, 2023, 77-100. https://edabyt.gr/wp-content/uploads/2025/02/%CE%92%CE%9F%CE%A5%CE%9B%CE%93%CE%91%CE%A1%CE%97%CE%A3-%CE%94%CE%B7%CE%BC%CE%BF%CF%83%CE%B9%CE%B5%CF%85%CE%BC%CE%AD%CE%BD%CE%BF.pdf
Abstract
One of the Fragments of the Antikythera Mechanism, Fragment D, has not been mechanically correlated with the remaining surviving fragments of the Mechanism, since the day of its discovery. For Fragment D has been suggested that it could be one of the gears that would move the hypothetical Venus planet indicator, but to date the hypothesis of the existence of the planets in the Antikythera Mechanism has not been proven, as no mechanical parts related to the motion of the planets, survive. Our team, The Functional Reconstruction of Antikythera Mechanism – The FRAMe Project, correlated Fragment D with the preserved gears of Fragment A. The mechanical correlation of Fragments D and A shows the existence of the fourth lunar cycle on the Antikythera Mechanism, the Draconic cycle. Until this correlation, the Mechanism of Antikythera presented (through its gears), the three lunar cycles Sidereal, Synodic and Anomalistic, while the fourth lunar cycle, the Draconic, which determines whether an eclipse will occur, was not represented in the Mechanism. By the connection of Fragments D and A, the four lunar cycles, which were known in antiquity, are presented on the Antikythera Mechanism. We found that the correlation of the Synodic with the Draconic cycle of the Mechanism created the sequence of eclipse events, which is engraved on the Saros spiral: The ancient Craftsman took into account the relative positions of the Draconic pointer within the ecliptic limits and the Lunar pointer when aimed towards or opposite the Golden Sphere-Sun. The eclipse events calculation is based entirely on a pure mechanical procedure, without any external/non-related information. A critical observation was also made on this geared device: The inherent mechanical errors present in any gear machine (as also in the Antikythera Mechanism with triangular teeth, non-perfect shape of gear teeth, and the eccentricity errors), lead to some deviations from the ideal position of its pointers, resulting in calculation errors such as the omitted eclipses and the mismatches on the classification procedure. The inherent gearing errors create deviations in the calculations between the bronze gears and the digital/3D representations.
Reconstructing the Antikythera Mechanism’s Central Front Dial parts – Division and Placement of the Zodiac Dial ring – 2025a.
Aristeidis Voulgaris, Christophoros Mouratidis, Andreas Vossinakis.
Journal of the Astronomical History and Heritage, 28(1), 257–279. https://dds.sciengine.com/cfs/files/pdfs/view/1440-2807/B14DB9E8860042A1AF8B2997E4F33D33.pdf
Abstract
In this paper we analyze, discuss and present the design of the Antikythera Mechanism’s central front parts. Based on the aligned and visual images of the same scale of Fragment C front/back face and X-ray CT scans, we designed and reconstructed in bronze, the four independent parts comprising the central front dial. We then correlated the zodiac dial ring with 365 equal subdivisions/days and we investigated the number of days per
astronomical season and per zodiac month. Then, we adopted a specific number of equal subdivisions/days per zodiac month and we engraved these on the bronze zodiac month ring. The different number of days per zodiac month created 12 unequal central angles on the zodiac dial ring and therefore the solar anomaly and the unequal time span of the astronomical seasons were well represented on the Antikythera Mechanism. In this way, the functionality of the central front dial of the Mechanism was achieved by adopting the minimum number of hypotheses.
The reconstruction of the Antikythera Mechanism Instruction Manual after a diligent Study and Analysis of the Back Cover Inscription Part-1 (pages 01-60) & Part-2 (pages 60-100).
Voulgaris, A., Irakleous, C., Mouratidis, C., Vossinakis A.
Unpublished work, Uploaded in Arxiv on 25 Jul 2022, rev. 2023. https://arxiv.org/pdf/2207.12009
Abstract Part-1
The Inscriptions which were on the Back Cover of the Antikythera Mechanism were the User’s Manual of the Antikythera Mechanism. In the Back Cover Inscription Part-1 text, the Presentation, Position, and Operation of the outer parts of the Mechanism’s Front face was engraved by the ancient manufacturer. Although this technical text is partially/poorly preserved, useful information, results, and conclusions were retracted by studying the words/sentences adapted on their original geometrical positions, concerning the image of the Mechanism’s front face. After the study and the analysis of the preserved text and its characteristics, the missing text completion is presented. A significant part of the reconstructed text was reproduced using the preserved words and phrases. In many cases the reconstructed text can be considered as definite. The use of the author’s Antikythera Mechanism functional model was critical for the analysis and understanding the preserved text, contributing to the design and reconstruction of the Mechanism’s Front Face parts, which are not preserved nowadays.
Abstract Part-2
We present the Part-2 text reconstruction of the Back Cover Inscription (BCI). In the BCI Part-2 text, the ancient manufacturer of the Antikythera Mechanism has engraved the information related to the Presentation, the Position, and the Operation of the outer operational mechanical parts, which were located at the Back plate. Although this technical text is also partially/poorly preserved as is the Part-1, the words and the phrases present a characteristic repeatability, especially when the Engraver presents and describes the two helical (spiral) dials, their pointers and their parts. A significant percentage of the missing text was completed using the existed words and phrases. Some of the spiral parts’ were preserved on the text, and their geometrical characteristics were studied and named based on Archimedes’ work Περί Ελίκων (De Lineis Spiralibus). In order to describe the geometry and the position of some of the mechanical parts mentioned in the text, words from the technical text of Heron’s of Alexandria work Περί Διόπτρας (Dioptra), as well as from works written by Ptolemy, Euclid and Geminus were used. The style of the reconstructed text was based on the preserved text’s style and is presented at the simplest grammar and syntax form of the koine Hellenist Greek language. In many cases the reconstructed text can be considered as definite.
Is there something missing from the Antikythera Mechanism? Was it a mechanical Planetarium, positioner? or a Luni solar Time calculator device? Reconstructing the lost parts of b1 gear and its Cover Disc.
Voulgaris, A., Mouratidis, C., Vossinakis, A., Roumeliotis M.
Unpublished work, Uploaded in Arxiv on 8 Jul 2024. https://arxiv.org/pdf/2407.15858
Abstract
We present the observations and the results of our experience from a large number of “flight hours” in constructing, assembling, handling, testing, studying and interacting with our functional reconstruction models of Antikythera Mechanism. We constructed our models according to the X-ray tomographies and without any use of modern stabilization parts (screws, nuts etc.). Simple typical bronze material (not with special alloys) was used in the construction, while (most of) the gears were cut from simple bronze discs with thickness ≈2mm and with triangular shaped teeth (not in modern involute shape). The bronze (not iron or steel) shafts have dimensions conforming to the original parts of the ancient artifact. The assembly of the parts was done after a careful study of the Personal Constructional Characteristics and the Design Style of the ancient Craftsman, which are visible or even hidden on the parts of the Antikythera Mechanism Fragments. During the extensive use of our models, it was concluded that two important and mandatory indicators are missing from all current reconstructions of the Antikythera Mechanism. The absence of these two indicator dials makes it difficult to properly operate the Mechanism and their existence is necessary, in order for the Antikythera Mechanism to be considered as a complete and self-contained operational time-measuring device. The two procedures related to the (poorly) preserved remains were located on gear b1 and the lost Cover Disc of the b1 gear. The reconstruction of those missing parts was achieved by paying special attention to the Personal Constructional Characteristics of the ancient Craftsman. The extensive analysis of the Antikythera Mechanism’s calibrated scales leads to the understanding of the Mechanism as a luni-solar time measuring device, as opposed to the notion that it was a mechanical planetarium presenting the hypothesized planetary motions and positions.