> With Europa we are looking at 20km+ of multiple layers of exotic Europan ice with composition and properties we know very little about, have zero experience with.

I mean, that's why we go. Clipper is going to figure out, in part, whether we actually need to go down 20km or if we can just scoop up stuff kicked by cryovulcanism into low orbit. https://www.nasa.gov/missions/are-water-plumes-spraying-from...