Editing Armillary sphere (section)

{{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]]