Stella octangula

The stella octangula (eight-pointed star), also known as the stellated octahedron, is the polyhedral compound of two tetrahedra. It was given its name by Johannes Kepler in 1609, though it was known to earlier geometers. It is both the simplest regular polyhedral compound and the simplest non-convex uniform polyhedron. Image File history File links Stella_octangula. ... Image File history File links Stella_octangula. ... A polyhedral compound is a polyhedron which is itself composed of several other polyhedra sharing a common centre, the three-dimensional analogs of polygonal compounds such as the hexagram. ... For academic journal, see Tetrahedron A tetrahedron (plural: tetrahedra) is a polyhedron composed of four triangular faces, three of which meet at each vertex. ... Johannes Kepler Johannes Kepler (December 27, 1571 – November 15, 1630), a key figure in the scientific revolution, was a German mathematician, astronomer and astrologer of famed brilliance. ... // Events April 4 – King of Spain signs an edit of expulsion of all moriscos from Spain April 9 – Spain recognizes Dutch independence May 23 - Official ratification of the Second Charter of Virginia. ... A polyhedron is a geometric shape which in mathematics is defined by three related meanings. ...

The vertices of the two tetrahedra define a cube and the intersection of the two an octahedron, which shares the same face-planes as the compound. Thus it is a stellation of the octahedron, and in fact, the only stellation thereof. Three dimensions A cube (or hexahedron) is a Platonic solid composed of six square faces, with three meeting at each vertex. ... An octahedron (plural: octahedra) is a polyhedron with eight faces. ... Stellation is a process of constructing new polygons (in two dimensions), new polyhedra in three dimensions, or in general new polytopes in n dimensions. ...

See also

• Polyhedron
• Merkaba
• Polyhedron models