Planisphaerium

From Wikipedia, the free encyclopedia

"Planisphaerium" can also refer to an album by Wormed.

The Planisphaerium was a work by Ptolemy in which he explored the mathematics of mapping figures inscribed in the celestial sphere onto a plane by stereographic projection, a method of projection that preserves the properties of circles. The work would be instrumental in the use of plane astrolabes.