View source for Armillary sphere

{{short description|Model of objects in the sky consisting of a framework of rings}}
[[File:Armillary sphere with astronomical clock.jpg|thumb|upright|[[Jost Bürgi]] and [[Anton Eisenhoit|Antonius Eisenhoit]]: Armillary sphere with [[astronomical clock]], made in 1585 in [[Kassel]], now at [[Nordiska Museet]] in Stockholm]]

An '''armillary sphere''' (variations are known as '''spherical [[astrolabe]]''', '''armilla''', or '''armil''') is a model of [[astronomical object|objects]] in the sky (on the [[celestial sphere]]), consisting of a spherical framework of [[wikt:ring|ring]]s, centered on [[Earth]] or the [[Sun]], that represent lines of [[celestial coordinate system|celestial longitude and latitude]] and other astronomically important features, such as the [[ecliptic]]. As such, it differs from a [[celestial globe]], which is a smooth sphere whose principal purpose is to map the [[constellation]]s. It was invented separately, in [[ancient China]] possibly as early as the 4th century BC and [[ancient Greece]] during the 3rd century BC, with later uses in the [[Islamic world]] and [[Medieval Europe]].

With the Earth as center, an armillary sphere is known as ''[[geocentric model|Ptolemaic]]''. With the Sun as center, it is known as ''[[Copernican heliocentrism|Copernican]]''.<ref name="EB1911">{{EB1911|inline=y|wstitle=Armilla|volume=2|pages=575–576|last=Huggins |first=Margaret Lindsay |author-link=Margaret Lindsay Huggins}}</ref>

The [[flag of Portugal]] features an armillary sphere. The armillary sphere is also featured in Portuguese [[heraldry]], associated with the [[Portuguese discoveries]] during the [[Age of Exploration]]. [[Manuel I of Portugal]], for example, took it as one of his symbols where it appeared on his standard, and on early Chinese export [[ceramic]]s made for the Portuguese court. In the flag of the [[Empire of Brazil]], the armillary sphere is also featured.

The [[Beijing Capital International Airport]] Terminal 3 features a large armillary sphere metal sculpture as an exhibit of [[Chinese inventions]] for international and domestic visitors.
[[File:BJ 渾天儀Armillary sphere 北京首都國際機場 Beijing Capital International Airport 紫薇辰恆 Ziwei Chenheng Aug-2010 visitors.JPG|thumb|Chinese Armillary sphere at [[Beijing Capital International Airport]] Ziwei Chenheng Aug-2010]]

== Description and use ==
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{{Hatnote|This section, edited from the ''[[Encyclopedia Britannica]]'' first edition, refers to labels in the diagram below. (Open it in a second window on your screen for easy magnified reference.)}}
[[Image:EB1711 Armillary Sphere.png|thumb|upright|left|Armillary sphere diagram]]

The exterior parts of this machine are a [[Wiktionary:compages|compages]] [or framework] of brass rings, which represent the principal circles of the heavens:

# The equinoctial ''A'', which is divided into 360 degrees (beginning at its intersection with the ecliptic in [[Aries (constellation)|Aries]]) for showing the sun's [[right ascension]] in degrees; and also into 24 hours, for showing its right ascension in time.
# The ecliptic ''B'', which is divided into 12 signs, and each sign into 30 degrees, and also into the months and days of the year, in such a manner that the degree or point of the ecliptic on which the sun appears, on any given day, stands over that day in the circle of months.
# The [[tropic of Cancer]] ''C'', touching the ecliptic at the beginning of [[Cancer (constellation)|Cancer]] in ''e'', and the [[tropic of Capricorn]] ''D'', touching the ecliptic at the beginning of [[Capricorn (constellation)|Capricorn]] in ''f''; each circle 23{{frac|1|2}} degrees from the equinoctial circle.
# The [[Arctic Circle]] ''E'', and the [[Antarctic Circle]] ''F'', each circle 23{{frac|1|2}} degrees from its respective pole at ''N'' and ''S''.
# The [[equinoctial colure]] ''G'', passing through the north and south poles of the heavens at ''N'' and ''S'', and through the equinoctial points in Aries and Libra, in the ecliptic.
# The [[solstitial colure]] ''H'', passing through the poles of the heavens, and through the solstitial points in Cancer and Capricorn, in the ecliptic. Each quarter of the equinoctial [[colure]] is divided into 90 degrees, from the equinoctial to the poles of the world, for showing the [[declination]] of the sun, moon, and stars; and each quarter of the solstitial colure, from the ecliptic as ''e'' and ''f'', to its poles ''b'' and ''d'', for showing the [[Celestial latitude|latitude]] of the stars.

In the north pole of the ecliptic is a nut ''b'', to which is fixed one end of the quadrantal wire.  To the other end is a small sun ''Y'', which is carried around the ecliptic ''B''—''B'', by turning the nut. In the south pole of the ecliptic is a pin ''d'', on which another quadrantal wire is situated, with a small moon ''Ζ'' upon it, which may be moved around by hand. A mechanism causes the moon to move in an orbit which crosses the ecliptic at an angle of 5{{frac|1|3}} degrees, to opposite points called the [[lunar nodes]], and allows for shifting these points backward in the ecliptic, as the lunar nodes shift in the heavens.

Within these circular rings is a small terrestrial globe ''I'', fixed on an axis ''K'', which extends from the north and south poles of the globe at ''n'' and ''s'', to those of the celestial sphere at ''N'' and ''S''. On this axis the flat celestial meridian ''L'' is fixed, which may be set directly over the meridian of any place on the globe, so as to keep over the same meridian upon it. This flat meridian is graduated the same way as the brass meridian of the common globe, and its use is much the same.

To this globe is fitted the movable horizon ''M'', so as to turn upon the two strong wires proceeding from its east and west points to the globe and entering the globe at the opposite points off its equator, which is a movable brass ring set into the globe in a groove all around its equator. The globe may be turned by hand within this ring, so as to place any given meridian upon it, directly under the celestial meridian ''L''. The horizon is divided into 360 degrees all around its outermost edge, within which are the points of the [[compass]], for showing the amplitude of the sun and the moon, both in degrees and points. The celestial meridian ''L'' passes through two notches in the north and south points of the horizon, as in a common globe: if the globe is turned around, the horizon and meridian turn with it. At the south pole of the sphere is a circle of 25 hours, fixed to the rings. On the axis is an index which goes around that circle, if the globe is turned around its axis.

[[File:Clock Tower from Su Song's Book desmear.JPG|thumb|upright|The original diagram of Chinese scientist [[Su Song]]'s book of 1092 showing the inner workings of his [[clocktower]]; a [[Escapement|mechanically rotated]] armillary sphere crowns the top.]]

The globe assembly is supported on a pedestal ''N'', and may be elevated or depressed upon the joint ''O'', to any number of degrees from 0 to 90 by means of the arc ''P'', which is fixed in the strong brass arm ''Q''. The globe assembly slides in the upright piece ''R'', in which is a screw at ''r'', to fix it at any proper elevation.

In the box ''T'' are two wheels (as in Dr Long's sphere) and two pinions, whose axes come out at ''V'' and ''U''; either of which may be turned by the small winch ''W''. When the winch is put upon the axis ''V'', and turned backward, the terrestrial globe, with its horizon and celestial meridian, keep at rest; and the whole sphere of circles turns round from east, by south, to west, carrying the sun ''Y'', and moon ''Z'', round the same way, and causing them to rise above and set below the horizon. But when the winch is put upon the axis ''U'', and turned forward, the sphere with the sun and moon keep at rest; and the earth, with its horizon and meridian, turn round from horizon to the sun and moon, to which these bodies came when the earth kept at rest, and they were carried round it; showing that they rise and set in the same points of the horizon, and at the same times in the hour circle, whether the motion be in the earth or in the heaven. If the earthly globe be turned, the hour-index goes round its hour-circle; but if the sphere be turned, the hour-circle goes round below the index.

And so, by this construction, the machine is equally fitted to show either the real motion of the earth, or the apparent motion of the heavens.

To reset the sphere for use, one must first slacken the screw ''r'' in the upright stem ''R'', and taking hold of the arm ''Q'', move it up or down until the given degree of latitude for any place lies at the side of the stem ''R''; then the axis of the sphere will be properly elevated, so as to stand parallel to the axis of the terrestrial globe, if the globe assembly is to be aligned to north and south by a small compass: once this is done, the user must count the latitude from the north pole, upon the celestial meridian ''L'', down towards the north notch of the horizon, and set the horizon to that latitude. The user then must turn the nut ''b'' until the sun ''Y'' comes to the given day of the year in the ecliptic, and the sun will be at its proper place for that day.

To find the place of the moon's [[ascending node]], and also the place of the moon, an [[ephemeris]] must be consulted to set them right accordingly. Lastly, the user must turn the winch ''W'', until either the sun comes to the meridian ''L'', or until the meridian comes to the sun (moving the sphere or globe at the user's discretion), and then set the hour-index to the XII, marked noon, the whole sphere will be reset. Then the user must turn the winch, and observe when the sun or moon rises and sets in the horizon. The hour-index will show the times thereof for the given day.<ref>Elements of the general description incorporate text from the ''[[Encyclopædia Britannica]]'' First Edition (1771).</ref>

==History==
===China===
[[File:Ancient Beijing observatory 10.jpg|upright=1.2|thumb|Armillary sphere at [[Beijing Ancient Observatory]], replica of an original from the [[Ming dynasty]]]]
[[File:性命圭旨 周天璇璣圖.png|thumb|Armillary Sphere 周天璇璣圖, 1615 ''[[Xingming guizhi]]'']]

Throughout [[China|Chinese]] history, [[astronomer]]s have created '''celestial globes''' ({{zh|t=渾象|p=húnxiàng}}) to assist the observation of the stars. The Chinese also used the armillary sphere in aiding [[calendar|calendrical]] computations and calculations.

According to [[Joseph Needham]], the earliest development of the armillary sphere in [[China]] goes back to the astronomers [[Shi Shen]] and [[Gan De]] in the 4th century BC, as they were equipped with a primitive single-ring armillary instrument.<ref name="needham volume 3 343">Needham, Volume 3, 343.</ref> This would have allowed them to measure the north polar distance (declination) a measurement that gave the position in a ''xiu'' (right ascension).<ref name="needham volume 3 343"/> Needham's 4th century BC  dating, however, is rejected by British sinologist [[Christopher Cullen]], who traces the beginnings of these devices to the 1st century BC.<ref>Christopher Cullen, "Joseph Needham on Chinese Astronomy", ''Past and Present'', No. 87 (May, 1980), pp. 39–53 (45)</ref>

During the [[Western Han dynasty]] (202 BC{{snd}}9 AD) additional developments made by the astronomers [[Luoxia Hong]] (落下閎), Xiangyu Wangren, and Geng Shouchang (耿壽昌) advanced the use of the armillary in its early stage of evolution. In 52 BC, it was the astronomer Geng Shouchang who introduced the first permanently fixed equatorial ring of the armillary sphere.<ref name="needham volume 3 343"/> In the subsequent [[Eastern Han dynasty]] (23–220 AD) period, the astronomers Fu An and Jia Kui added the ecliptic ring by 84 AD.<ref name="needham volume 3 343"/> With the famous statesman, astronomer, and inventor [[Zhang Heng]] (張衡, 78–139 AD), the sphere was totally complete in 125 AD, with horizon and meridian rings.<ref name="needham volume 3 343"/> The world's first water-powered celestial globe was created by [[Zhang Heng]], who operated his armillary sphere by use of an inflow [[Water clock|clepsydra]] clock.

Subsequent developments were made after the Han dynasty that improved the use of the armillary sphere. In 323 AD the Chinese astronomer Kong Ting was able to reorganize the arrangement of rings on the armillary sphere so that the ecliptic ring could be pegged on to the equator at any point desired.<ref name="needham volume 3 343"/> The Chinese astronomer and mathematician [[Li Chunfeng]] (李淳風) of the [[Tang dynasty]] created one in 633 AD with three spherical layers to calibrate multiple aspects of astronomical observations, calling them 'nests' (chhung).<ref name="needham volume 3 343"/> He was also responsible for proposing a plan of having a sighting tube mounted ecliptically in order for the better observation of celestial latitudes. However, it was the Tang Chinese astronomer, mathematician, and monk [[Yi Xing]] in the next century who would accomplish this addition to the model of the armillary sphere.<ref name="needham volume 3 350">Needham, Volume 3, 350.</ref> Ecliptical mountings of this sort were found on the armillary instruments of Zhou Cong and Shu Yijian in 1050, as well as Shen Kuo's armillary sphere of the later 11th century, but after that point they were no longer employed on Chinese armillary instruments until the arrival of the [[Europeans in Medieval China|European Jesuits]].

[[Image:ChineseCelestialGlobe.JPG|thumbnail|upright|Celestial globe from the [[Qing dynasty]]]]
In 723 AD, Yi Xing (一行) and government official Liang Ling-zan (梁令瓚) combined Zhang Heng's water powered celestial globe with an [[escapement]] device. With drums hit every quarter-hour and bells rung automatically every full hour, the device was also a [[striking clock]].<ref>Needham (1986), Volume 4, Part 2, 473–475.</ref> The famous [[clock tower]] that the Chinese polymath [[Su Song]] built by 1094 during the [[Song dynasty]] would employ Yi Xing's escapement with waterwheel scoops filled by clepsydra drip, and powered a crowning armillary sphere, a central celestial globe, and mechanically operated manikins that would exit mechanically opened doors of the clock tower at specific times to ring bells and gongs to announce the time, or to hold plaques announcing special times of the day. There was also the scientist and statesman [[Shen Kuo]] (1031–1095). Being the head official for the Bureau of Astronomy, Shen Kuo was an avid scholar of astronomy, and improved the designs of several astronomical instruments: the [[gnomon]], armillary sphere, clepsydra clock, and sighting tube fixed to observe the [[pole star]] indefinitely.<ref name="sivin III 17">Sivin, III, 17</ref> When Jamal al-Din of Bukhara was asked to set up an 'Islamic Astronomical Institution' in Khubilai Khan's new capital during the [[Yuan dynasty]], he commissioned a number of astronomical instruments, including an armillary sphere. It was noted that "Chinese astronomers had been building [them] since at least 1092".<ref>S. Frederick Starr, ''Lost Enlightenment: Central Asia's Golden Age from the Arab Conquest to Tamerlane''. Princeton University Press, 2013, p. 452.</ref>

===Indian Subcontinent ===
[[File:Armillary sphere.JPG|thumb|Armillary sphere at the [[Garh Palace, Kota]]]]
The armillary sphere was used for observation in India since early times, and finds mention in the works of [[Aryabhata|Āryabhata]] (476 CE).<ref name=Sarma08>Sarma (2008), ''Armillary Spheres in India''</ref> The ''Goladīpikā''—a detailed treatise dealing with globes and the armillary sphere was composed between 1380 and 1460 CE by [[Parameśvara]].<ref name=Sarma08/> On the subject of the usage of the armillary sphere in India, Ōhashi (2008) writes: "The Indian armillary sphere (''gola-yantra'') was based on equatorial coordinates, unlike the Greek armillary sphere, which was based on ecliptical coordinates, although the Indian armillary sphere also had an ecliptical hoop. Probably, the celestial coordinates of the junction stars of the lunar mansions were determined by the armillary sphere since the seventh century or so."<ref name=Ohashiast-inst>Ōhashi (2008), ''Astronomical Instruments in India''</ref>

=== Hellenistic world and ancient Rome ===
{{further|Planetarium|Antikythera mechanism}}
[[File:Wall painting - armillary sphere - Stabiae (villa di San Marco) - Stabia MAdSLdO 2535 - 02.jpg|thumb|Mythological figures within an armillary sphere in a fragmentary fresco from [[Stabiae]], mid-1st century AD]]
The [[Greek astronomy|Greek astronomer]] [[Hipparchus]] ({{Circa|190|120 BC}}) credited [[Eratosthenes]] (276{{snd}}194 BC) as the inventor of the armillary sphere.<ref>Williams, p. 131</ref><ref>Walter William Bryant: ''[https://archive.org/details/AHistoryOfAstronomy/page/n33/mode/2up A History of Astronomy]'', 1907, p. 18</ref><ref>John Ferguson: ''Callimachus'', 1980, {{ISBN|978-0-8057-6431-4}}, p. 18</ref><ref>Henry C. King: ''The History of the Telescope'', 2003, {{ISBN|978-0-486-43265-6}}, p. 7</ref><ref>Dirk L. Couprie, Robert Hahn, Gerard Naddaf: ''Anaximander in Context: New Studies in the Origins of Greek Philosophy'', 2003, {{ISBN|978-0-7914-5537-1}}, p. 179</ref> Names of this device in Greek include {{lang|grc|ἀστρολάβος}} ''astrolabos'' and {{lang|grc|κρικωτὴ σφαῖρα}} ''krikōtē sphaira'' "ringed sphere".<ref>{{LSJ|a)strola/bos|ἀστρολάβος}}, {{LSJ|krikwto/s|κρικωτή|ref}}.</ref> The English name of this device comes ultimately from the [[Latin]] ''armilla'' (circle, bracelet), since it has a skeleton made of graduated metal circles linking the [[celestial pole|pole]]s and representing the [[equator]], the [[ecliptic]], [[meridian (astronomy)|meridians]] and [[Circle of latitude|parallel]]s. Usually a ball representing the [[Earth]] or, later, the [[Sun]] is placed in its center. It is used to demonstrate the [[celestial mechanics|motion]] of the [[star]]s around the Earth. Before the advent of the European [[telescope]] in the 17th century, the armillary sphere was the prime instrument of all astronomers in determining celestial positions.

[[File:Ptolemy 1476 with armillary sphere model.jpg|thumb|left|upright|''[[Ptolemy]] with an armillary sphere model'', by [[Joos van Ghent]] and [[Pedro Berruguete]], 1476, [[Louvre]], Paris]]
In its simplest form, consisting of a ring fixed in the plane of the equator, the ''armilla'' is one of the most ancient of astronomical instruments. Slightly developed, it was crossed by another ring fixed in the plane of the meridian. The first was an equinoctial, the second a solstitial armilla. Shadows were used as indices of the sun's positions, in combinations with angular divisions. When several rings or circles were combined representing the great circles of the heavens, the instrument became an armillary sphere.<ref name="EB1911"/>

Armillary spheres were developed by the [[Hellenistic civilization|Hellenistic Greeks]] and were used as teaching tools already in the 3rd century BC. In larger and more precise forms they were also used as observational instruments. However, the fully developed armillary sphere with nine circles perhaps did not exist until the mid-2nd century AD, during the [[Roman Empire]].<ref name="encyclopedia britannica armillary sphere"/> Eratosthenes most probably used a solstitial armilla for measuring the [[obliquity]] of the ecliptic. Hipparchus probably used an armillary sphere of four rings.<ref name="encyclopedia britannica armillary sphere">Editors of Encyclopædia Britannica. (16 November 2006). "[https://www.britannica.com/science/armillary-sphere Armillary Sphere]." ''[[Encyclopædia Britannica]]''. Accessed 14 October 2017.</ref> The [[Greco-Roman world|Greco-Roman]] geographer and astronomer [[Ptolemy]] ({{Circa|100|170 AD}}) describes his instrument, the ''astrolabon'', in his ''[[Almagest]]''.<ref name="encyclopedia britannica armillary sphere"/> It consisted of at least three rings, with a graduated circle inside of which another could slide, carrying two small tubes positioned opposite each other and supported by a vertical plumb-line.<ref name="EB1911"/><ref name="encyclopedia britannica armillary sphere"/>

===Medieval Middle East and Europe===
[[File:Spherical astrolabe islamic march 2024.JPG|thumb|left|upright|The spherical [[astrolabe]] from medieval [[Islamic astronomy]], c. 1480, in the [[Museum of the History of Science, Oxford]]<ref name="LindbergShank2013">{{cite book|last1=Lindberg|first1=David C.|author-link1=David C. Lindberg|last2=Shank|first2=Michael H.|title=The Cambridge History of Science: Volume 2, Medieval Science|url=https://books.google.com/books?id=ZMNkAwAAQBAJ&pg=PT173|access-date=15 May 2018|date=7 October 2013|publisher=Cambridge University Press|isbn=978-1-316-02547-5|page=173}}</ref>]]
[[Image:Sandro Botticelli 052.jpg|thumb|upright|An armillary sphere [[Saint Augustine in His Study (Botticelli, Ognissanti)|in a painting]] by [[Republic of Florence|Florentine]] Italian artist [[Sandro Botticelli]], c. 1480.]]
[[File:Représentation ottomane sphère armilaire - XVIe.jpg|thumb|upright|An [[Ottoman Empire|Ottoman]] illustration of an armillary sphere, 16th century]]

[[Islamic astronomy|Persian and Arab astronomers]] such as [[Ibrahim al-Fazari]] and [[Abbas Ibn Firnas]] continued to build and improve on armillary spheres. The spherical astrolabe, a variation of both the [[astrolabe]] and the armillary sphere, was likely invented during the [[Middle Ages]] in the [[Islamic Golden Age|Middle East]].<ref>[[Emilie Savage-Smith]] (1993). "Book Reviews", ''Journal of Islamic Studies'' '''4''' (2), pp. 296–299. {{blockquote|"There is no evidence for the Hellenistic origin of the spherical astrolabe, but rather evidence so far available suggests that it may have been an early but distinctly Islamic development with no Greek antecedents."}}</ref> About 550 AD, Christian philosopher [[John Philoponus]] wrote a treatise on the astrolabe in Greek, which is the earliest extant treatise on the instrument.<ref>Modern editions of [[John Philoponus]]' treatise on the astrolabe are ''De usu astrolabii eiusque constructione libellus'' (On the Use and Construction of the Astrolabe), ed. Heinrich Hase, Bonn: E. Weber, 1839, {{OCLC|165707441}} (or id. Rheinisches Museum für Philologie 6 (1839): 127–71); repr. and translated into French by Alain Philippe Segonds, ''Jean Philopon, traité de l'astrolabe,'' Paris: Librairie Alain Brieux, 1981, {{OCLC|10467740}}; and translated into English by H.W. Green in R.T. Gunther, ''The Astrolabes of the World'', Vol. 1/2, Oxford, 1932, {{OL|18840299M}} repr. London: Holland Press, 1976, {{OL|14132393M }} pp. 61–81.</ref> The earliest description of the spherical astrolabe dates back to the Persian astronomer [[Al-Nayrizi|Nayrizi]] ([[floruit|fl.]] 892–902). [[Pope Sylvester II]] applied the use of sighting tubes with his armillary sphere in order to fix the position of the [[pole star]] and record measurements for the [[tropics]] and [[equator]], and used armillary spheres as a teaching device.<ref>Darlington, 679–670.</ref>

===Korea===
[[File:Korean celestial globe.jpg|thumb|left|Korean celestial globe]]
Chinese ideas of astronomy and astronomical instruments were introduced to Korea, where further advancements were also made. [[Jang Yeong-sil]], a [[Korean people|Korean]] inventor, was ordered by [[King Sejong the Great of Joseon]] to build an armillary sphere. The sphere, built in 1433 was named Honcheonui (혼천의,渾天儀).

The [[Honcheonsigye]], an armillary sphere activated by a working clock mechanism was built by the Korean astronomer Song Iyeong in 1669. It is the only remaining [[astronomical clock]] from the [[Joseon dynasty]]. The mechanism of the armillary sphere succeeded that of Sejong era's armillary sphere (Honŭi 渾儀, 1435) and celestial sphere (Honsang 渾象, 1435), and the Jade Clepsydra (Ongnu 玉漏, 1438)'s sun-carriage apparatus. Such mechanisms are similar to Ch'oe Yu-ji (崔攸之, 1603~1673)'s armillary sphere(1657). The structure of time going train and the mechanism of striking-release in the part of clock is influenced by the crown escapement which has been developed from 14th century, and is applied to gear system which had been improved until the middle of 17th century in Western-style clockwork. In particular, timing device of Song I-yŏng's Armillary Clock adopts the early 17th century pendulum clock system which could remarkably improve the accuracy of a clock.<ref>KIM Sang-Hyuk, [http://m.riss.kr/search/detail/DetailView.do?p_mat_type=be54d9b8bc7cdb09&control_no=3b48615694989343ffe0bdc3ef48d419 A study on the operation mechanism of song I-yong`s armillary clock], Ph.D dissertation, JoongAng University</ref>

[[File:Fotothek df tg 0005688 Astronomie ^ Vermessung ^ Messinstrument.jpg|thumb|left|upright|Tycho Brahe's zodiacal armillary sphere, from his ''Astronomiae Instauratae Mechanica'' (Wandesburg, 1598), p. 36.]]

===Renaissance===

Further advances in this instrument were made by Danish astronomer [[Tycho Brahe]] (1546–1601), who constructed three large armillary spheres which he used for highly precise measurements of the positions of the stars and planets. They were described in his ''Astronomiae Instauratae Mechanica''.<ref>{{cite web |url=http://www.sil.si.edu/DigitalCollections/HST/Brahe/brahe-introduction.htm#book |title=Astronomiæ instauratæ mechanica by Tycho Brahe: Introduction |first=Ronald |last=Brashear |work=Special Collections Department |publisher=Smithsonian Institution Libraries |date=May 1999 |access-date=July 11, 2020}}</ref>

Armillary spheres were among the first complex mechanical devices. Their development led to many improvements in techniques and design of all mechanical devices. [[Renaissance]] scientists and public figures often had their portraits painted showing them with one hand on an armillary sphere, which represented the zenith of [[wisdom]] and [[knowledge]].

The armillary sphere survives as useful for teaching, and may be described as a skeleton celestial globe, the series of rings representing the great circles of the heavens, and revolving on an axis within a horizon. With the earth as center such a sphere is known as Ptolemaic; with the sun as center, as Copernican.<ref name="EB1911"/>
<gallery>
File:Roger-bacon-statue.jpg|Sculpture of 13th-century English scientist [[Roger Bacon]] holding an armillary sphere, [[Oxford University Museum of Natural History]]
File:Jan Gossaert - Portrait of a Young Princess (possibly Dorothea of Denmark).jpg|Young girl with an astronomical instrument, by [[Jan Gossaert]], c. 1520-1540
File:Antoine Crespin.PNG|Portrait in the frontispiece of [[Antoine Crespin]]'s ''Propheties par l'astrologue du treschrestien Roy de France et de Madame la Duchesse de Savoye'', Lyon, France, 1572
Crespi L'Ingegno.jpg|''[[Ingenuity (Crespi)|Allegory of Ingenuity]]'' by [[Giuseppe Crespi]], c. 1695
File:Francesco de Mura - Allegory of Arts, c1750-1775 - Louvre.jpg|''Allegory of the Arts'', by [[Francesco de Mura]], c. 1750
</gallery>

A representation of an armillary sphere is present in the modern [[flag of Portugal]] and has been a national symbol since the reign of [[Manuel I of Portugal|Manuel I]].
[[Image:Genève - La sphère armillaire (1952).jpg|thumb|upright| The Armillary sphere in Geneva]]

== Paralympic Games ==
An artwork-based model of an Armillary sphere has been used since the March 1, 2014 to light the [[Paralympic]] heritage flame at [[Stoke Mandeville Stadium]], United Kingdom.  The sphere includes a wheelchair that the user can rotate to spark the flame as part of a ceremony to celebrate the past, present and future of the Paralympic Movement in the UK.  The Armillary Sphere was created by artist [[Jon Bausor]] and will be used for future Heritage Flame events.  The flame in the first-ever ceremony was lit by [[London 2012]] gold medallist [[Hannah Cockroft]].<ref>{{cite web |url=http://www.paralympic.org/news/first-ever-heritage-flame-lit-stoke-mandeville-historic-moment-paralympic-movement |title=First ever Heritage Flame lit at Stoke Mandeville in a historic moment for Paralympic Movement |date=3 January 2014 |website=www.paralympic.org}}</ref>

== Heraldry and vexillology ==
[[File:Flag of Portugal (official).svg|thumb|right|220px|The [[flag of Portugal]] features a pronounced armillary sphere]]
The armillary sphere is commonly used in [[heraldry]] and [[vexillology]], being mainly known as a symbol associated with [[Portugal]], the [[Portuguese Empire]] and the [[Portuguese discoveries]].

In the end of the 15th century, the armillary sphere became the personal [[heraldic badge]] of the future King [[Manuel I of Portugal]], when he was still a [[Prince of Portugal|Prince]]. The intense use of this badge in documents, monuments, flags and other supports, during the reign of Manuel I, transformed the armillary sphere from a simple personal symbol to a national one that represented the Kingdom of Portugal and in particular its [[Portuguese Empire|Overseas Empire]]. As a national symbol, the armillary sphere continued in use after the death of Manuel I.

In the 17th century, it became associated with the [[Colonial Brazil|Portuguese dominion of Brazil]]. In 1815, when [[Kingdom of Brazil|Brazil gained the status of kingdom]] united with that of Portugal, its coat of arms was formalized as a golden armillary sphere in a blue field. Representing Brazil, the armillary sphere became also present in the arms and the flag of the [[United Kingdom of Portugal, Brazil and the Algarves]]. When [[Empire of Brazil|Brazil became independent as an empire]] in 1822, the armillary sphere continued to be present in its national arms and in its national flag. The celestial sphere of the present [[Flag of Brazil]] replaced the armillary sphere in 1889.

The armillary sphere was reintroduced in the [[Coat of arms of Portugal|national arms]] and in the national [[Flag of Portugal]] in 1911.
[[File:6' Armillary Sphere @ San Jacinto Battle Field, Texas.jpg|thumb|200px|6' Armillary Sphere at the San Jacinto Battle Field in La Porte, Texas]]

== See also ==
{{div col}}
* {{annotated link|Antikythera mechanism}}
* {{annotated link|Celestial globe}}
* {{annotated link|Atlas (statue)}}
* {{annotated link|Chinese constellations}}
* ''{{annotated link|De sphaera mundi}}'', describes the late medieval (Ptolemaic) cosmos
* {{annotated link|Jang Yeong-sil}}
* {{annotated link|Orrery}}, a free-standing {{annotated link|Solar System model}}
* {{annotated link|Prague astronomical clock|aka=Prague Orloj}}
* {{annotated link|Santucci's Armillary Sphere}} – largest in the world
* {{annotated link|Torquetum}}
* {{annotated link|Noyes Armillary Sphere}}
{{div col end}}

==References==
{{Reflist}}

===Sources===
* Encyclopædia Britannica (1771), "Geography".
* Darlington, Oscar G. "Gerbert, the Teacher," ''The American Historical Review'' (Volume 52, Number 3, 1947): 456–476.
* Kern, Ralf: Wissenschaftliche Instrumente in ihrer Zeit. Vom 15. – 19. Jahrhundert. Verlag der Buchhandlung Walther König 2010, {{ISBN|978-3-86560-772-0}}
* [[Joseph Needham|Needham, Joseph]] (1986). ''Science and Civilization in China: Volume 3''. Taipei: Caves Books, Ltd.
* [[Nathan Sivin|Sivin, Nathan]] (1995). ''Science in Ancient China''. Brookfield, Vermont: VARIORUM, Ashgate Publishing
* [[Henry Smith Williams|Williams, Henry Smith]] (2004). ''A History Of Science''. Whitefish, MT: Kessinger Publishing. {{ISBN|1-4191-0163-3}}.

== External links ==
{{Commons}}
* [http://www.hps.cam.ac.uk/starry/armillary.html Starry Messenger] {{Webarchive|url=https://web.archive.org/web/20141012191511/http://www.hps.cam.ac.uk/starry/armillary.html |date=2014-10-12 }}
* [https://www.whipplemuseum.cam.ac.uk/explore-whipple-collections/astronomy/armillary-spheres-and-teaching-astronomy Armillary Spheres and Teaching Astronomy | Whipple Museum] 
* [http://www.astromedia.de AstroMedia* Verlag in Germany offers a cardboard construction kit for an armillary sphere ("Das Kleine Tischplanetarium")]

{{Greek astronomy}}
{{Solar System models}}
{{Portal bar|Astronomy|Stars|Spaceflight|Outer space|Solar System}}
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{{DEFAULTSORT:Armillary Sphere}}
[[Category:Ancient Greek astronomy]]
[[Category:Ancient inventions]]
[[Category:Astronomical instruments]]
[[Category:Chinese inventions]]
[[Category:Danish inventions]]
[[Category:Greek inventions]]
[[Category:Hellenistic engineering|Sphere]]
[[Category:Heraldic charges]]
[[Category:Historical scientific instruments]]
[[Category:Iranian inventions]]