فراشانش ِ استریونگاریک farâšâneš-e estereyonegârik
*Fr.: projection stéréographique*
A graphical method of depicting three-dimensional geometrical objects
in two dimensions. In a → *planispheric astrolabe*,
it is the projection of a point of the celestial sphere onto the equatorial plane, as
seen from one of the poles. The center of projection
is the South pole for the northern hemisphere, and the North pole for
the southern hemisphere. In this operation
the projection of any circle of the sphere remains a circle on the projection plane
and moreover the projection does not alter angles. → *stereographic*; → *projection* |