RE: Another step in colonizing Mars
Well, Mars still has a thin atmosphere (if I'm not mistaken) mostly made of CO2 and yeah, it doesn't have a magnetic field. The scientist thought, for starters, to use inflatable modules that would be covered with martian regolith (with mixture of water and other stuff) to create a (it's not correct per say) "clay" cover over the module and protect the inhabitants from radiation. That would cut some cost and not need to send construction materials to Mars.
If I remember correctly, NASA's plan was to send modules (something that looked like a cylinder, don't know the size...), containing food and supplies, before the astronauts arrived on Mars and to repeat that process over and over, until they would have a permanent settlement.
There are a few ideas (some of them crazy) out their on how to develop and build a martian base/colony. One the biggest entrepreneur (Elon Musk) is already planning and developing technologies and projects for a mars colony. And I imagine that he'll try to do it cost efficient.
The first date (planned) for a human mission to Mars is... 2020? That's the date proposed by NASA.
Well if the inflatable structures do work with what you say not so but yet it is "clay" then it could all work, and I believe Elon Musk is gonna do it before NASA to be honest, he had so much failures and still everyone said he's not gonna suceed but he believed in himself and his team and look where he's at now... And despite aiming for mars he's so down to earth (pun intended) :D
It's really great that men like Elon Musk exist (that are visionary and have the will/power/money to realize what they envision), it gives us hope for (I couldn't say for a better future...) an interesting and exciting future! I can only speculate the reason why he (Elon Musk) would take such endeavour, but, I'm happy about it :).
Yes, we all have a system of "be born, go to good school, get good job, get married, get kids, and retire and enjoy" but did you know he moved from his parents alone as a kid and worked in 30 minute shifts with 30 workers in some narrow mine where if you would be more than 30 minutes you are risking death, and he and only I think 2 people stayed after the first week of 30 starting workers.. HE WAS A KID... My hat's off for Elon Musk.