Antikythera mechanism: Difference between revisions

The '''Antikythera mechanism''' ({{IPAc-en|ˌ|æ|n|t|ɪ|ˈ|k|ɪ|ˈ|θ|ɪər|ə}} {{respell|AN|tihtik|KIHih|therTHEER|ə}}, {{IPAc-en|USalso|ˌ|æ|n|t|aɪ|k|ɪ|ˈ|-}} {{respell|AN|ty|kih|-}})<ref>{{dict.com|Antikythera}}</ref><ref>{{OED|Antikythera mechanism|1572890579}}</ref> is an [[Ancient Greece|Ancient Greek]] hand-powered [[orrery]] (model of the Solar System), described as the oldest known example of an [[analogue computer]]<!-- see the talk page before changing "analogue computer" to "analog computer" --><ref>{{cite journal

}}</ref> Machines with similar complexity did not appear again until the [[astronomical14th clock]]s of [[Richard of Wallingford]]century in thewestern 14th centuryEurope.<ref name=marchant-06 />

The German philosopherphilologist [[Albert Rehm]] became interested in the device;, he was theand first to proposeproposed that it was an astronomical calculator.<ref>{{Cite web|url=http://pao.chadwyck.co.uk/articles/displayItemFromId.do?QueryType=articles&ItemID=0215-1954-098-00-000001|title=Albert Rehm zum Gedächtnis|access-date=24 August 2023|archive-date=9 September 2023|archive-url=https://web.archive.org/web/20230909175427/https://www.proquest.com/legacyredirect/pao/docview/1294505584|url-status=live}}</ref><ref name="TFreeth2013">{{cite journal |last1=Freeth |first1=Tony |title=Building the Cosmos in the Antikythera Mechanism |journal=Proceedings of Science |date=29 March 2013 |page=018 |doi=10.22323/1.170.0018 |url=https://pos.sissa.it/170/018/pdf |access-date=13 March 2021 |doi-access=free |archive-date=1 November 2020 |archive-url=https://web.archive.org/web/20201101230420/https://pos.sissa.it/170/018/pdf |url-status=live }}</ref>

In 2022 researchers proposed the mechanism's initial calibration date, not construction date, could have been 23 December 178 BC. Other experts propose 204 BC as a more likely calibration date.<ref name="AT-20220412"/><ref name="ARX-20220328"/> Machines with similar complexity did not appear again until the fourteenth century, with early examples being [[astronomical clock]]s of [[Richard of Wallingford]] and [[Giovanni Dondi dell'Orologio|Giovanni de' Dondi]] in the fourteenth century.<ref name=marchant-06 />

The front dial has two concentric circular scales. The inner scale marks the Greek signs of the zodiac, with division in degrees. The outer scale, which is a moveablemovable ring that sits flush with the surface and runs in a channel, is marked off with what appear to be days and has a series of corresponding holes beneath the ring in the channel.

Since the discovery of the mechanism more than a century ago, this outer ring has been presumed to represent thea 365&nbsp;-day Egyptian solar calendar, but recent research (Budiselic, et al., 2020) challenged this presumption and provided direct statistical evidence itthere isare most354 likelyintervals, dividedsuggesting intoa 354lunar intervalscalendar.<ref name=budiselic>{{cite report |author1=Budiselic |display-authors=et al |date=December 2020 |title=Antikythera mechanism: Evidence of a lunar calendar |place=Newark, UK |publisher=British Horological Institute |website=BHI.Co.UK |url=https://bhi.co.uk/wp-content/uploads/2020/12/BHI-Antikythera-Mechanism-Evidence-of-a-Lunar-Calendar.pdf |access-date=12 December 2020 |archive-date=13 December 2020 |archive-url=https://web.archive.org/web/20201213144005/https://bhi.co.uk/wp-content/uploads/2020/12/BHI-Antikythera-Mechanism-Evidence-of-a-Lunar-Calendar.pdf |url-status=live }}</ref> Since this initial discovery, two research teams, using different methods, independently calculated the interval count. Woan and Bayley calculate 354–355 intervals using two different methods, confirming with higher accuracy the Budiselic et al. findings and noting that "365 holes is not plausible".<ref>{{cite report |author1=Woan and BayleyarXiv |date=February 2024 |title= An improved calendar ring hole-count for the Antikythera mechanism |arxiveprint=2403.00040 |last1= Woan |first1= Graham |last2= Bayley |first2= Joseph |class= physics.hist-ph }}</ref> Malin and Dickens' best estimate is 352.3±1.5 and they concludeconcluded that the number of holes, (N,) "has to be integral and the SE ([[standard error]]) of 1.5 indicates that there is less than a 5% probability that N is not one of the six values in the range 350 to 355. The chances of N being as high as 365 are less than 1 in 10,000. While other contenders cannot be ruled out, of the two values that have been proposed for N on astronomical grounds, that of BTDRBudiselic et al. (354) is by far the more likely."<ref name=budiselic /><ref>{{cite report |author1= Malin and Dickens |date=April 2024 |title=How Many Days in an Egyptian Year? Evidence from the Antikythera Mechanism |page= 144 |place=Newark, UK |publisher=British Horological Institute |website=BHI.Co.UK |url=https://bhi.co.uk/wp-content/uploads/2024/04/04-HJApril24-AOTM.pdf |access-date=15 April 2024 }}</ref><ref>{{cite journal |last1=Woan |first1=Graham |last2=Bayley |first2=Joseph |title=An improved calendar ring hole-count for the Antikythera mechanism |journal=The Horological Journal |date=July 2024 |arxiv=2403.00040 |url=https://bhi.co.uk/wp-content/uploads/2024/06/07-HJJuly24-AOTM-2.pdf |access-date=4 July 2024}}</ref>

<ref name=pavlus>{{cite web| last=Pavlus| first=John| title=Small Mammal, Behind the Scenes: Lego Antikythera Mechanism| date=9 December 2010| url=https://m.youtube.com/watch?v=RLPVCJjTNgk| archive-url=https://ghostarchive.org/varchive/youtube/20211107/RLPVCJjTNgk| archive-date=7 November 2021 | url-status=live| publisher=Small Mammal| access-date=19 July 2018}}{{cbignore}}</ref>

* {{cite journal | year = 2022 | title = An Ancient Greek Astronomical Calculation Machine Reveals New Secrets | journal = Scientific American | volume = 326 | issue = 1 | pages = 24–33 | url = https://www.scientificamerican.com/article/an-ancient-greek-astronomical-calculation-machine-reveals-new-secrets/ | doi = 10.1038/scientificamerican0122-24 | pmid = | author = Freeth, T. | doi-broken-date = 31 January 2024 | bibcode = | access-date = 18 April 2023 | archive-date = 23 March 2023 | archive-url = https://web.archive.org/web/20230323142308/https://www.scientificamerican.com/article/an-ancient-greek-astronomical-calculation-machine-reveals-new-secrets/ | url-status = live }}