And Musk created SpaceX, which now has a sprawling rocket design complex not far from Los Angeles International airport.
In the most recent "Iron Man" films, the vast SpaceX research and design lab served as the backdrop for billionaire Tony Stark's company -- which is appropriate because Stark, played by Robert Downey Jr., was modeled after Musk. The film's director even gave Musk one of the "Iron Man" suits.
As for sending people to Mars, "I think it would be the most difficult thing that humanity has ever tried to do," Musk said. "The Earth has been around for four billion years and in all that time, it's been confined to one planet. That's a long time."
"And now for the first time in almost four billion years, it's been possible -- very difficult, but possible -- for life to extend to another planet," he said. "If we can take advantage of that opportunity, who knows how long that window will be open?"