Last summer, billionaires Jeff Bezos and Richard Branson competed to one-up each other's accomplishments in space flight while Elon Musk's SpaceX continued to make history with its reusable launches. But are all these efforts nothing more than wasteful vanity projects among the uberrich? I'm joined today by Robert Zubrin to talk about why the emergence of a private space economy and the prospects of colonizing the solar system should excite us.

Robert Zubrin is President of Pioneer Astronautics and the founder and President of the Mars Society, an international organization dedicated to furthering the exploration and settlement of Mars. An aerospace engineer and energy expert, Robert is the author of several books including "The Case for Mars" and "The Case for Space."