3D KSP Solar System Scale Model (base tool)
This model displays an accurate layout of the KSP system from game-start (UT=0, or universal time 0) to as much as 500 in-game years. AN/DN, Pe/Ap, and SOI, as well as body size and atmosphere of all bodies are included (moons too). Users should feel free to download a copy and modify it to suit their purposes.
Known issues:
- Body in "Focus View" drop-down often needs to be selected twice in order to display the target body at intended zoom level.
More information available at the KSP forums.