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I did something similar a few years back with that 22gb displacement map, although much more accurately and easily: it's a piece of cake to directly ray trace a displaced sphere: you basically intersect two spheres (the outer and inner radius), which gives you a ray interval that you can "march" through. At each step while marching, you look at the surface height at the current point, compare it to your point's radius, and if it's greater then you've intersected the surface since the last step (and can perform bisection method to refine the intersection distance to machine precision).

That's actually how the displacement of the intersection is done here - marching in the range between spheres. Bisection, however, wont work at shallow angles.

What a very nicely done, high quality project. I found it engaging to read the reasoning along the way to a very neat bit art.

There was a time when such data-mangling was way, way off limits, in some A/C'ed computer room somewhere .. and now here I am, setting up anaconda on the trains' own wifi as a landscape scrolls past, rendering the moon while I can see the real one out the window ..

On reddit the OP said

>The visualization and video of the Moon were made with python and 3D ray-tracing (it is not a photo!)

The Moon made twice, at home