Armstrong's words, "One small step for a man.....

Mr Armstrong has long insisted that he meant to say “one small step for a man . . .” — which would have been a more meaningful and grammatically correct version, free of tautology. But even the astronaut himself could not be sure.

“Damn, I really did it. I blew the first words on the Moon, didn’t I?” he is reported to have asked officials later, amid uncertainty as to whether he had blown the moment or simply been drowned out by static interference as his words were relayed 250,000 miles back to Earth.

Now, after almost four decades, the spaceman has been vindicated. Using high-tech sound analysis techniques, an Australian computer expert has rediscovered the missing “a” in Mr Armstrong’s famous quote. Peter Shann Ford ran the Nasa recording through sound-editing software and clearly picked up an acoustic wave from the word “a”, finding that Mr Armstrong spoke it at a rate of 35 milliseconds — ten times too fast for it to be audible.