Icosahedron Day
Today is a day to celebrate the regular icosahedrons . The regular convex icosahedron is one of the platonic solids , though there is also a regular concave icosahedron named the Great Icosahedron . A regular icosahedron is formed by putting 20 identical equilateral triangles together into a convex or concave polyhedron . It will have 12 vertices, 20 faces, and 30 edges. (A non-regular icosahedron would can consist of any polyhedron with 20 faces with a variety of vertices and edges.) We celebrate icosahedrons on March (3rd month) 20 because it's composed of triangles (3 sides), and 20 of them. By Theon at French Wikipedia - own work. Transferred from fr.wikipedia to Commons.; Transfer was stated to be made by Theon., GFDL, https://commons.wikimedia.org/w/index.php?curid=3563566