I never understood why colonizing Mars is needed. Even if a meteorite hits Earth or Yellowstone erupts, Earth would be more "hospitable" to life than any other planet in our solar system because Earth has a lot of resources that are right under our noses: breathable atmosphere, radiation shielding, easily mined metals and organic matter. It's much easier to build and maintain a bio-dome in the Sahara desert, Arctic r…
>I never understood why colonizing Mars is needed. Personally I see quite a few positive things behind colonising Mars. I think it's not about having a "backup", it's not about resources (or in a really long time) it's about the challenge. If we can put our best engineers to solve how we re-use and recycle water, how we grow crops in extreme condition, how to control the O2 CO2 cycle (at a larger scale than on the sp…
Besides the obvious - large-scale terraforming - a "practice" settlement of Mars gives us an opportunity to innovate and refine practically every engineering skill, form of social organization, or general skillful endeavor in humanity's repertoire.
Metallurgy, genetics, geology, farming, medicine, psychology - all of these fields are bound to discover new phenomenon and methodologies under the constraints and conditions of an alien planet.
Not to be glib, but necessity is mother of invention. And there is no necessity as powerful as the drive for survival.