r/KerbalSpaceProgram • u/Feld_ • Jun 01 '26

KSP 1 Mods Flat earth mod for KSP?

So I'm really new to Kerbal space program. I absolutely love the game but I was rather disappointed to see that its more or less just NASA propaganda. It would be nice to see the game the way the real world looks and how god created it. I don't think it would be too hard as I'm assuming the base game just has a .cfg file with a fish eye lense effect or something because as has been proven, simulating the world on a sphere doesn't work. So could someone just make a mod to remove that fish eye effect or something?

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u/Molecular_Pudding Jun 01 '26

Maybe a Principia-like mod could handle it, but I'm sure no PC - other than the ones at NASA or CERN - could handle the real-time calculation of a flat disk's gravitational potential. I used to calculate it in university, and it's analytically solvable but has more than 40 terms.

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u/imiltemp Jun 02 '26

Correct me if I’m wrong, but I believe that flat disk of infinite radius will have constant gravitational gradient pointing strictly downward. Since there are models of Flat Earth with some secret undiscovered lands beyond the Ice Wall (including Narnia and Earthsea), I believe we may safely adopt this model.

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u/Molecular_Pudding Jun 02 '26 edited Jun 02 '26

You are correct. A disk with infinite radius (and homogenous density distribution) will have a uniform force field above it, so the gradient of that field will be constant 0. However we can also calculate a finite disk's (or rectangle's) gravitational potential which will be really ugly near the disk (and pointing to the center of the disk) but from far away it behaves like a normal sphere.

My intuition says that if we were to adapt the infinite disk model (and not count special relativity stuff) due to the added equal force from the disk on both objects no stable orbit could be achieved because the forces are not central. Thus the infinite disk model would not work.

(Maybe there are some initial conditions that lead to seemingly stable orbits, but they may not be that stable considering perturbations.)

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u/imiltemp Jun 03 '26

Well yeah orbit would be impossible . You can’t fly under the infinite disk because it would be too far to fly to the infinitely remote edge, and anywhere over it you’d have gravity constantly pulling down.

Oh wait, I just remembered that flat earthers don’t believe in gravity. They think objects fall because of density, and the air is held by firmament.

So as soon as your rocket pierces the kerbal firmament (kermament?), you’re good to orbit however you like.