This Is The Biggest Problem Facing Elon Musk's Dream Of Building A City On Mars

Through SpaceX, Elon Musk has done more than perhaps anyone to rekindle interest in space travel. And he hasn't been shy about his ambitions for the company, stating that he hasn't taken SpaceX public because of his unwavering commitment to its central mission: making humans an interplanetary species. Needless to say, there's nothing easy about that. In fact, the Mars One program, whose proponents think it can be done within a decade, recently had their plan savaged as untenable by researchers a...