It’s no secret now that NASA astronaut Rich Clifford had Parkinson’s Disease during his last Space Shuttle mission in 1996. But the fact was secret at the time, and Clifford is telling the story of his disease and its influence on his space career in a forthcoming documentary titled “The Astronaut’s Secret.”

Clifford previewed the documentary and discussed his NASA work and Parkinson’s Disease during a presentation today to the John Locke Foundation’s Shaftesbury Society. Clifford also addressed the future of the American space program, including the comments in the video below about the next step in space exploration.

2:35 p.m. update: Click play below to watch the full 44:31 event.

You’ll find other John Locke Foundation video presentations here.