Sometimes, when using Stella 4d (available here) to make various polyhedra, I lose track of how I got from wherever I started to the final step. That happened with this fractured version of an octahedron.
I created this using Stella 4d, which you can try for free right here. It’s much like a tessellation, but in three dimensions instead of two.
I created this image using Stella 4d, which you can try for free right here. It’s much like a tessellation, but in three dimensions instead of two.
I made this rotating virtual model using Stella 4d: Polyhedron Navigator, which you can try for yourself at http://www.software3d.com/Stella.php. This solid is different from most two-part polyhedral compounds because an unusually high fraction of one polyhedron, the yellow octahedron, is hidden inside the compound’s other component.
While examining different facetings of the dodecahedron, I stumbled across one which is also a compound of ten elongated octahedra.
Here’s what this compound looks like with the edges and vertices hidden:
Next, I’ll put the edges and vertices back, but hide nine of the ten components of the compound. This makes it easier to see the single elongated octahedron which is still shown.
Here’s what this elongated octahedron looks like with all those vertices and edges hidden from view.
I made all these polyhedral transformations using Stella 4d, a program you can try for yourself at this website. Stella includes a “measurement mode,” and, using that, I was able to determine that the short edge to long edge ratio in these elongated octahedra is 1:sqrt(2).
The next thing I wanted to try was to make the octahedra regular. Stella has a function for that, too, and here’s the result: a compound of ten regular octahedra.
My last step in this polyhedral exploration was to form the dual of this solid. Since the octahedron’s dual is the cube, this dual is a compound of ten cubes.
I made this using Stella 4d: Polyhedron Navigator. You can try this program for free at http://www.software3d.com/Stella.php.
This is the three-dimensional version of what is called a tessellation in two dimensions. It fills space, and can be continued in all directions.
Software used: Stella 4d, available here.