A celestial globe consisting of metal hoops; used by early astronomers to determine the positions of stars WordNet 3.0 & Open English WordNet

An armillary sphere is a model of objects in the sky, consisting of a spherical framework of rings, centered on Earth or the Sun, that represent lines of celestial longitude and latitude and other astronomically important features, such as the ecliptic. Wikipedia

A physical model of the celestial sphere Wikipedia Disambiguation

Model of objects in the sky Wikidata

Astronomical device that is used to measure celestial coordinates and to display the motion of celestial bodies. OmegaWiki

An instrument consisting of graduated metal circles used to represent the motions of celestial bodies around the earth. Wiktionary

Instrument consisting of graduated metal circles. Wiktionary (translation)