About 60 Minutes Season 35, Episode 18 : The Last Frontier/North Korea/The Wrong Man

"The Last Frontier" talks to astronauts and scientists about the explosion of the Space Shuttle Columbia. "North Korea" examines the rarely visited country and witnesses the malnutrition, desperation and deprivation that many people face there. "The Wrong Man" looks at how the FBI wrongly investigated a CIA agent for spying. "Andy Rooney" talks about the recent space shuttle Columbia disaster.