I saw Buzz Aldrin talk. He said that we have to make three successful manned missions to Mars and back before we can think of colonizing it. Three indicates we

I saw Buzz Aldrin talk. He said that we have to make three successful manned missions to Mars and back before we can think of colonizing it. Three indicates we have solved the fundamental issues of safety, sanity [1], and propulsion. I believe Elon Musk and SpaceX will do it. [1] Russia has begun training astronauts for the 500-day project by experimenting with placing them in isolation