The Hubble and the Future of Space Exploration

Astronaut-astronomer John Grunsfeld calls the Hubble Space Telescope "arguably the most important scientific instrument ever created," important enough for him and others to risk their lives walking in space for five days to make repairs. Now it's almost time to come home. We look at what they did and what the Hubble might find as it looks back farther than ever toward the origin of the universe and the beginning of time. We also consider what's next for the manned space program. Would a return to the Moon and a visit to Mars be cheaper and more effective with robots?