The Ptolemaic system of the universe with the spherical Earth in the center. Complete with the crystal sphere, blinking stars, the day-night Earth cycle and axis tilt.

Video demo here, here, here and here!

Two versions: 

1. THE VERTICAL DOME

Illustrating the rotation of the system from a top view. The spheres are cyclically shifting up and down, illustrating the orbital tilt. Animated in Geometry Nodes.

2. THE ROTATING SPHERES

The spheres are rotating in multiple axis, emphasizing the "orb-nature" of the universal structure.

Enjoy ! Happy Blending !

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NOTE - The Ptolemaic model has specific orbital cycle parameters and epicycles defined. This setup is true to the spirit and overall dynamics of the model, but it is not following those parameters exactly. (You can, of course, modify the setup to parameters you wish)

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NOTE

-(Since it is a concept demonstration, it is kept as simple as possible.) The GeoNodes trees are kept clean for easier readability and have detailed explanations. Everything is built from the base. The point of these setups is to provide a base core of the concept, node from node, instead of contracting all into node groups with exposed settings, which makes everything harder to read and dissect.

You can embellish, refine as you wish based on the core or realize your own ideas.

-Read the text description, it has a lot of useful info !