Load this sandbox and observe the unsettling phenomena: both the parent body and the moon have rather typical settings for rocky objects.
Another equally as disturbing visual has been spotted: Bunop can become invisible after your craft enters the SOI of its moon.
From Valve
In case it helps, I was using:
Nvidia GeForce GT 430
Intel Core 2 Duo E8400
4GB DDR2
Windows 10 version 1607