Dr. Neil deGrasse Tyson joins Massimo and Julia to discuss the need for a space program. Many scientists (and most people in the skeptic community) simply assume that funding outlets like NASA are a good idea. But, can scientists justify the enormous expense involved, not just in terms of their personal curiosity, but as a matter of tangible and intangible benefits to society at large? Should we go back to the Moon and establish a permanent base? Is it worth the expense and likely risk to human life to attempt a mission to Mars? What is a space station for, anyway?

Dr. Tyson is an astrophysicist by training and director of the Hayden Planetarium at the American Museum of Natural History in Manhattan. He is also the host of PBS's science NOW. His latest book is "The Pluto Files: The Rise and Fall of America's Favorite Planet."