Great icosahedron
The Great icosahedron is a regular polyhedron is one of the Keplerian star bodies; It is bounded by 60 isosceles triangles and 120 irregular triangles.
Formation
Body is the Dodekaederstern. The Great icosahedron is the result of 20 mutually intersecting equilateral triangles, which can be found in Dodekaederstern; the triangles intersect at an angle of ≈ 70.5 ° (or ≈ 109.5 ° supplementär ). Two triangles meet at one of its edges, where they form a " rib angle " of ≈ 41.8 °. This star body is like a reduced, " ausgeschabter " Dodekaederstern, with the cut-outs 60 in the form of irregular tetrahedra.