Compound of five icosahedra

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Short description: Polyhedral compound
Compound of five icosahedra
UC47-5 icosahedra.png
Type Uniform compound
Index UC47
Polyhedra 5 icosahedra
Faces 40+60 Triangles
Edges 150
Vertices 60
Symmetry group icosahedral (Ih)
Subgroup restricting to one constituent pyritohedral (Th)

File:Compound of five icosahedra.stl The compound of five icosahedra is uniform polyhedron compound. It's composed of 5 icosahedra, rotated around a common axis. It has icosahedral symmetry Ih.

The triangles in this compound decompose into two orbits under action of the symmetry group: 40 of the triangles lie in coplanar pairs in icosahedral planes, while the other 60 lie in unique planes.

Cartesian coordinates

Cartesian coordinates for the vertices of this compound are all the cyclic permutations of

(0, ±2, ±2τ)
(±τ−1, ±1, ±(1+τ2))
(±τ, ±τ2, ±(2τ−1))

where τ = (1+5)/2 is the golden ratio (sometimes written φ).

References

  • Skilling, John (1976), "Uniform Compounds of Uniform Polyhedra", Mathematical Proceedings of the Cambridge Philosophical Society 79 (3): 447–457, doi:10.1017/S0305004100052440 .