Saturday afternoon marks the 50th anniversary of the launch of the Apollo 13 mission, dubbed the "successful failure" of the Apollo program.
Although an explosion prevented astronauts James Lovell Jr., John Swigert Jr. and Fred Haise Jr. from participating in the third planned lunar landing, NASA's engineers and flight control teams at the Apollo Mission Control Center worked with the astronauts to safely return them to Earth.
Perhaps you watched the afternoon launch on TV when it happened on April 11, 1970, or first learned about the mission watching the 1995 "Apollo 13" film.
NASA software engineer and historian Ben Feist, along with a dedicated team of historians, researchers and audio, film and visual experts, have digitized and restored footage and audio from the mission.
Everything is organized in the order it happened during the mission, from launch to the celebrated return of the astronauts to Earth.
Mission Control footage is married with film taken by the astronauts during their flight, as well as broadcasts about the mission. Every photo has been inserted when it was taken.
More than 7,200 hours from 50 different channels of Mission Control audio are synchronized to play out as they were spoken.
There were four missing tapes from Apollo 13 Mission Control that were recovered from the National Archives in fall 2019. They contain the audio from the time of the explosion aboard Apollo 13.
After being digitized and restored, it's the first time the recordings have been heard since they were used in the investigation of the accident in 1970.
The tapes disappeared for so long because they were packed away with the rest of the accident investigation material in 1972, according to an article by Catherine Baldwin, the NASA History Center's editor and social media coordinator. The article appeared in the latest edition of NASA History's News and Notes Newsletter.
The intriguing audio captures the range of emotions and magnitude of stress experienced by the astronauts and ground teams as they worked together to safely return the three men. It's a race against time over five days, 22 hours and 54 minutes.
At the beginning of the mission, there are jokes and fun, humanizing exchanges. After the success of the Apollo 11 mission in 1969, certain aspects of spaceflight had started to feel routine and it's palpable in the crew.
Everything takes a drastic shift when the explosion occurs on April 13, 1970. Tension, strain and long pauses as they search for words mark the exchanges between the astronauts and Mission Control.
Historic moments stand out, such as the infamous words spoken by Lovell of "Houston, we've had a problem," or Haise saying, "I didn't think I'd be back here this soon" as he and Lovell entered the lunar module after the explosion, preparing to use it as a "lifeboat."
The Apollo 13 project joins two others on Feist's site, a NASA-funded project including real-time explorations of the Apollo 11 and Apollo 17 missions.
Feist also performed audio restoration for the "Apollo 11" documentary, directed by Todd Douglas Miller, that aired on CNN in 2019 for the 50th anniversary of the mission.