>> reporter: musk says he kept wondering where are the hotels on marspromised in the movie 2001 space odyssey. >> i think mars would have good bars. the mars bar. >> reporter: he has his own vision on mars. populated and governed by entrepreneurs and people with a frontier mentality. while lit be exciting, it will be foor frar from easy. >> for the early people that go it will be difficult, dangerous, good chance you'll die. >> reporter: here on earth, he's developing a hyper loop, an underground vacuum tube that might be able to transport people and cars from new york to d.c. or l.a. to san francisco in less than an hour. he has strong ideas about how it would work. in a series of tweets he writes the hyper loop will prioritize