Preview: Man on the Moon - a CBS News Special

Two legends tell the story of the momentous 1969 moon walk. Apollo 11 commander Neil Armstrong and "CBS Evening News" anchor Walter Cronkite -- the man who made history and the man who reported it. Watch "Man on the Moon," hosted by "CBS Evening News" anchor Norah O'Donnell, Tuesday, July 16 at 10/9c on CBS.