Edge ball
The edge sphere is a sphere that touches all edges of the given polyhedron . In spatial geometry , it is the equivalent of the incircle of a polygon in plane geometry , in addition to the incircle .
The center point of an edge sphere must have the same distance from all edges. Only special polyhedra have an edge sphere, including the five Platonic solids , the Archimedean solids , uniform prisms and uniform antiprisms .
See also
Web links
- Venn diagram for the description of spheres around , in and edge of polyhedra