All this talk of sending people to Mars seems like putting the cart before the horse. If you have the technogy to not die on Mars, why not start with, say, underwater cities on Earth? At least there you'd have a ready supply of several life-supporting elements that would be absent on Mars. As it is, we've never tried to ensure anybody's long-term survival under conditions anywhere near as harsh as Mars — no air, no nitrogen, no readily available water, no indigenous animals to hunt, no fossil fuels, no geothermal energy, no hydro or windmills.
I never see plans to get around this with real-world technology — it's always just hand-waved as something we'll figure out. But it seems like the "letting people live natural lives under utterly inhospitable conditions" part has a lot more to do with ensuring humanity's survival than the Mars part.
I never see plans to get around this with real-world technology — it's always just hand-waved as something we'll figure out. But it seems like the "letting people live natural lives under utterly inhospitable conditions" part has a lot more to do with ensuring humanity's survival than the Mars part.