Forty Years in Search of an 'a'.

According to an article by BBC science correspondent Pallab Ghosh, Niel Armstrong slipped when he stepped onto the moon in 1969. Ever since the historic event, people have debated about whether the first words ever spoken on the moon were
"That's one small step for man, one giant leap for mankind", or
"That's one small step for a man, one giant leap for mankind".
Armstrong himself was convinced that he had said the second sentence -which does in fact make more sense. However, the words of the first man on the moon have often been quoted in the first form, in which the word 'man' has roughly the same meaning as 'mankind', so making the sentence slightly more cryptic.
In an effort to solve this debate, Dr Chris Riley, author of the book Apollo 11, An Owner's Manual, and forensic linguist John Olsson carried out the most detailed analysis yet of Neil Armstrong's speech patterns.
Riley and Olsson studied archive material o Neil armstrong speaking, recorded throughout and after the Apollo 11 mission. They then took the original magnetic tape recordings made at Johnson Space Centre, Houston, which have recently been re-digitised to make uncompressed, higher-fidelity audio recordings.
These clearer recordings indicate that the "r" in "for" and "m" in "man" run into each other, leaving no room for an "a".
But there is a rising pitch in the word "man" and a falling pitch when he says "mankind", which suggests Commander Armstrong was contrasting using speech. According to Mr. Olsson, this indicates that Armstrong "knows the difference between man and mankind and that he meant man as in 'a man' not 'humanity'."
Mr. Olsson says that Armstrong may have "subconsciously drawn from his poetic instincts to utter a phrase that, far from being incorrect - was perfect for the moment."