Well, the term "spelunking" may not be quite right here, so let me correct it to "surviving."
Presumably you know already about the great drive to have mankind settle on planet Mars. (Supposedly, as some folks claim, planet Earth will become inhabitable, sometime, in the very distant future (many thousands or even millions of years from now).
While that prediction may come true, I've yet to see any such futuristic "scenario" for Mars or other heavenly bodies that are on the "hot-list" wanting to move away from Earth.
