Nasa mission control helps Apollo 13’s cold, exhausted astronauts survive deadly carbon dioxide levels in the spacecraft. The constant troubleshooting to stay alive has taken its toll, and the crew of Jim Lovell, Jack Swigert and Fred Haise are at the limits of human endurance. Back home in Houston, the Nasa flight surgeon is so worried about the astronauts’ lack of sleep that he turns to Marilyn Lovell with an unusual request.For a film about how the crew made the makeshift CO2 adaptors: www.bbcworldservice.com/13minutesPresented by Kevin Fong.Archive: NasaStarring: Jim Lovell Merlin Merritt Anthony England Ed Smylie, courtesy of the Johnson Space Center Oral History Project Fred Haise Marilyn Lovell Ken Mattingly Charles A Berry Joe Kerwin Gerry GriffinWritten by Kevin Fong and Chris Browning Theme music by Hans Zimmer and Christian Lundberg for Bleeding Fingers Music.Produced by the BBC Radio Science Unit for the BBC World Service.