T minus 25 seconds…20 seconds and counting…T minus 15 seconds…guidance is internal…12, 11, 10, 9…ignition sequence starts…6, 5, 4, 3, 2, 1, 0…all engines running…lift-off, we have ...

Neil Armstrong thought he had a 50–50 shot at pulling it off. "There are so many unknowns ... But the 50th anniversary of Apollo 11 reminds us that this laughably ambitious goal has in fact ...