Armillary Sphere

An armillary sphere (variations are known as spherical astrolabe, armilla, or armil) is a model of objects in the sky (in the celestial sphere), consisting of a spherical framework of rings, centred on Earth, that represent lines of 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 constellations.

Read more about Armillary Sphere:  Description and Use of The Armillary Sphere

Famous quotes containing the word sphere:

    “Every person is responsible for all the good within the scope of his abilities, and for no more, and none can tell whose sphere is the largest.”
    —Gail Hamilton (1833–1896)