Back in July of 1969, the world watched in awe as astronauts Neil Armstrong and Buzz Aldrin became the first two people to walk on the Moon. The television broadcast captured the astronauts' landing, and as Armstrong disembarked the ship, he uttered a line that's become indelibly linked with the historic event.
While we all remember the line I'm referring to, what we haven't yet heard are the hours upon hours not included in the televised broadcast of communication between the three-man space team (including Michael Collins, who piloted the command module Columbia in lunar orbit while Armstrong and Aldrin were on the Moon) and mission control in Houston. NASA's archives from the Apollo missions included hundreds of 14-hour, 30-track long analog tapes. And earlier this week, in close collaboration with researchers at University of Texas Dallas, they released 19,000 hours worth of the digitized audio.
Though this audio has lived in NASA's records for just about half of a century now, the process of getting it to the people has laborious and full of unique challenges. Chief among them was that the original tapes could only be played on a piece of equipment from the 1960s called a SoundScriber, which could only manually play one track at a time. Digitizing the audio from the Apollo 11 mission alone would have taken at least 170 years, as estimated by one of the UT Dallas' researchers, John H.L. Hansen, who was tasked with finding a solution.
“We couldn’t use that system, so we had to design a new one,” Hansen explained on the UT Dallas blog. And heading a team alongside research scientist Dr. Abhijeet Sangwan, that's just what they did. The team built a 30-track read head of their own, capable of capturing all 30 tracks at the same time, and developed algorithms for parsing through and transcribing the audio.
A lot of clips feature long moments of silence between status updates, commands, and "roger thats," but every voice is colored by a special mixture excitement, anxiety, and nervousness. To hear for yourself, head over to the UT Dallas "Explore Apollo" website or to NASA's archival page.