1.9.4.2
Thanks to github user @dariasc for this:
Change SurfaceSampleObserver requirements: Changed to go inline with the current status.
https://wiki.kerbalspaceprogram.com/wiki/Research_and_Development#Levels
Thanks to github user @dariasc for this:
Change SurfaceSampleObserver requirements: Changed to go inline with the current status.
https://wiki.kerbalspaceprogram.com/wiki/Research_and_Development#Levels