[skykooler]

KSP's solution to the graphics problem is what they call "scaled space". Basically, nearby objects like your spaceship, the planet you're on, etc are rendered normally, but there is another copy of the solar system that's scaled down to 1/10 scale on another scene, and composited in behind everything. This is where things like orbit lines are drawn. It works well enough for KSP's solar system, which is rather small, but there are rendering issues with modpacks that add other solar systems far away from the sun; I suspect that since KSP2 is adding interstellar travel they are going to need to come up with another solution.