Twice Seven Is Fourteen

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Twice Seven Is Fourteen

Twenty-five

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Twenty-five

Cluster of Fifteen Decorated and Tightly-packed Truncated Octahedra

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Cluster of Fifteen Decorated and Tightly-packed Truncated Octahedra

This cluster was made of the same polyhedron from the previous post, repeated in a space-filling pattern, similar to a tessellation, but in three dimensions. The truncated octahedron has the property, unusual among polyhedra, that it can fill space without leaving any gaps. One of the fifteen truncated octahedra is i the center of the cluster, while another is attached to each of the central polyhedron’s fourteen faces.

Software used to create this includes three separate programs: Geometer’s Sketchpad, MS-Paint, and Stella 4d. This third program may tried for free, and/or purchased, at http://www.software3d.com/stella.php.

Truncated Octahedron Carousel

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Truncated Octahedron Carousel

The image on each face of this truncated octahedron is the one found in a previous post here, named Ten Circles, and was created with the use of two programs, Geometer’s Sketchpad and MS-Paint. As you’ll notice if you view other posts made today, though, the color scheme has been altered for this polyhedron.

Placing this image on each face of this polyhedron, as well as creating this rotating .gif file, required use of a third program, Stella 4d. This program may tried and/or purchased at http://www.software3d.com/stella.php. Unlike in the previous post, the images were “told” to stay upright while the polyhedron its rotates, creating a rotational effect in the yellow hexagonal faces, but a different effect in the red square faces. As far as I can tell, this is due to their different orientation in space, relative to the axis of rotation.

An Expansion of the Rhombicosidodecahedron, Using Trapezoids

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An Expansion of the Rhombicosidodecahedron, Using Trapezoids

Software credit: see http://www.software3d.com/stella.php

Op Art On a Rhombic Triacontahedron

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Op Art On a Rhombic Triacontahedron

The image on each face of this rhombic triacontahedron is the one found in the previous post here, named Ten Circles, and was created with the use of two programs, Geometer’s Sketchpad and MS-Paint.

Placing this image on each face of this polyhedron, as well as creating this rotating .gif file, required use of a third program, Stella 4d. This program may tried and/or purchased at http://www.software3d.com/stella.php.

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Spinning Truncated Icosahedron

I don’t reblog things here, but I do appreciate getting e-mail from my followers, and I don’t mind posting an occasional link. One of them, a gentleman named Donald, sent me this link to an interesting video of a spinning truncated icosahedron, viewed from both the inside and outside, and set to music. To see it, simply follow the link above. Thanks for the tip, Donald — this is a really cool video!

Captain Kirk, Mr. Spock, and Dr. McCoy on a Great Rhombicuboctahedron

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Captain Kirk, Mr. Spock, and Dr. McCoy On a Great Rhombcuboctahedron

If any doubt remained about my nerdiness, it’s gone now.

Software credit: see http://www.software3d.com/stella.php.

The Pentagonal Hexacontahedron, and Related Polyhedra

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The Pentagonal Hexacontahedron

As the dual of the snub dodecahedron, which is chiral, this member of the Catalan Solids is also chiral — in other words, it exists in left- and right-handed versions, known an entantiomers. They are mirror-images of each other, like left and right gloves or shoes. Here’s the other one, by comparison:

Penta Hexeconta enantiomer

It is always possible to make a compound, for a chiral polyhedron, from its two enantiomers. Here’s the one made from the two mirror-image pentagonal hexacontahedra shown above:

Compound of enantiomorphic pair

Stellating this enantiomorphic-pair-compound twenty-one times produces this interesting result:

stellating

And, returning to the unstellated enantiamorphic-pair-compound, here is its convex hull:

Convex hull

This convex hull strikes me as an interesting polyhedron in its own right, so I tried stellating it several times, just to see what would happen. Here’s one result, after seventeen stellations:

Stellation17

Software credit:  I made these rotating images using Stella 4d:  Polyhedron Navigator. That program may be bought at http://www.software3d.com/Stella.php, and has a free “try it before you buy it” trial download available at that site, as well. I also used Geometer’s Sketchpad and MS-Paint to produce the flat purple-and-black image found on faces near the top of this post (and, by itself, in the previous post on this blog), but I know of nowhere to get free trial downloads of these latter two programs.

Magenta Snowflake

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Magenta Snowflake