Tycho's 1581 Armillary Sphere

Armillary sphere, 1.6 meter in radius, built in 1581. Tycho rapidly gave up on using large versions of classical armillary sphere, as he found their accuracy compromised by flexing and bending due to the great weight of the various components. This lead to the design of equatorial armillaries.

Bibliography:

Thoren, V.E. 1973, Journal for the History of Astronomy, 4, 25.

Wesley, W.G. 1978, Journal for the History of Astronomy, 9, 42.

Tycho