I think just describing what's down there (or, more precisely -what we suspect might be down there, given our lack of knowledge!) may be sufficient.

That, and stressing that rather than committing years of your life to sitting inside a titanium cylinder being transported to wherever, you get to do real science within hours of entering an infinitely stronger titanium cylinder - and be back with your family in time for the weekend. (Yes, I exaggerate - but you get the idea. :)