Joseph Allen, the physicist, joined NASA in 1967 as a scientist astronaut. In conversation with Roy Plomley, he describes his lengthy training as an astronaut, the problems of space flight, and he describes his recent trip in the space shuttle to recover two satellites, which necessitated an unfettered walk in space.

[Taken from the original programme material for this archive edition of Desert Island Discs]

Favourite track: Minor Blue by David Darling