In geometry, the small stellapentakis dodecahedron is a nonconvex isohedral polyhedron. It is the dual of the truncated great dodecahedron. It has 60 intersecting triangular faces.
Proportions The triangles have two acute angles of arccos ( 1 2 + 1 5 5 ) ≈ 18.699 407 085 149 ∘ {\displaystyle \arccos({\frac {1}{2}}+{\frac {1}{5}}{\sqrt {5}})\approx 18.699\,407\,085\,149^{\circ }} and one obtuse angle of arccos ( 1 10 − 2 5 5 ) ≈ 142.601 185 829 70 ∘ {\displaystyle \arccos({\frac {1}{10}}-{\frac {2}{5}}{\sqrt {5}})\approx 142.601\,185\,829\,70^{\circ }} . The dihedral angle equals arccos ( − 24 − 5 5 41 ) ≈ 149.099 125 827 35 ∘ {\displaystyle \arccos({\frac {-24-5{\sqrt {5}}}{41}})\approx 149.099\,125\,827\,35^{\circ }} . Part of each triangle lies within the solid, hence is invisible in solid models.
References Wenninger, Magnus (1983), Dual Models, Cambridge University Press, ISBN 978-0-521-54325-5, MR 0730208
External links Weisstein, Eric W. "Small stellapentakis dodecahedron". MathWorld. Uniform polyhedra and duals




