Mark Harmon Wally Schirra Actor Peter Horton Documnetary Director Actor Daniel Hugh Kelly Gene Cernan Actor Ann Magnuson Dee O'Hara Actor Nick Searcy Deke Slayton Actor Tom Hanks Host Krista Adair Jo Schirra Actor Steve Hofvendahl Thomas Stafford Actor Fredric Lehne Walt Cunningham Actor Joshua Malina Tim Messick Actor Mark Rolston Gus Grissom Actor Max Wright Actor Stephen Root Actor David Andrews Actor Lane Smith Actor Lowell Fenner Actor Joe Farago Actor Remi Aubuchon Writer Lili Fini Zanuck Director Michael Bostick Producer Ron Howard Producer Brian Grazer Producer