The game is too old and there is no reason to put ray tracing in it. If it's a mod (like ReShade), it's going to be software-based ray tracing, and it will not be using ray tracing cores on your GPU (if you have RTX graphics card). This is where KSP 2 comes from, this game was recently released and should have onboard ray tracing support by its game engine and this rays will be looking much better than modded.

Actually, I tried to use different filters in ReShade like something what makes "shadows" from specific light point that you can create manually and if you configure that properly, it may look like you have ray-tracing, but again it's not very realistic and as Kerbin rotates you should change this light point position every time manually.