Hi @mikeyboy897, this sounds like an interesting idea!
I’m not sure why this particular image is not working. I am able to use an image as the material on an ellipsoid: see this Sandcastle example. But when I try to use your linked image, it is all white.
Could you take a look at czml ellipsoid Can't load image · Issue #7676 · CesiumGS/cesium · GitHub and see if it matches your issue? If it is the same problem, you could reopen the issue.
This older thread sounds like a similar problem.