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:

    If today there is a proper American “sphere of influence” it is this fragile sphere called earth upon which all men live and share a common fate—a sphere where our influence must be for peace and justice.
    Hubert H. Humphrey (1911–1978)