Astronauts Armstrong, Edwin "Buzz" Aldrin and Michael Collins left Earth on July 16 from Cape Kennedy in Florida. Armstrong and Aldrin stepped onto the moon a few days later. The men spent 21 hours, 36 minutes on the moon before joining back up with Collins in the command module.

More than a half billion people watched the televised first moonwalk July 20, 1969, where Neil Armstrong uttered the now-famous words, "That is one small step for man, one giant leap for mankind".

Decades afterwards, July 20th is a day that space buffs everywhere still celebrate.

Tweeting, Buzz Aldrin has shared his memories of the history-making mission as follows :