Discovery Channel chronicles the first 50 years of space travel - from the first Mercury flights through the Gemini program to the Apollo moon landings, the Space Shuttle, and the construction of the International Space Station - with this dazzling six-hour documentary. The programme incorporates interviews with eyewitnesses (astronauts John Glenn and Neil Armstrong among them) and original NASA mission footage that has been transferred to high-definition clarity. Actor Gary Sinise, who portrayed astronaut Ken Mattingly in `Apollo 13', narrates.