What is a mu file and how do I open a mu file?
MU is a 3D image file used by Kerbal Space Program, a game that allows players to build a space program. MU uses the filename model.mu and saves space shuttle and other object data. It uses a proprietary format only supported by the game. The MU file is accompanied by the part.cfg file that references it as a mesh. There are also .MBM files referenced by the MU file that contain the textures for the model. KSP models are built using Unity modelling software.
Relevant mu file links:How to open mu file on Youtube
How to open mu file on Wikipedia
How to open mu file on Microsoft.com