On May 18, 1969, NASA astronauts Thomas Stafford, John Young, and Eugene Cernan blasted off from Cape Canaveral aboard the Apollo 10 lunar module, the fourth manned mission in the US Apollo Space program and only the second after Apollo 8 to orbit the moon. Its mission was to circle the moon and thoroughly test the components and procedures to pave the way for the first lunar landing. The mission went flawlessly and without incident — At least that's what everyone believed.
However, that view has changed somewhat since February 22, after NASA released a digital recording of strange 'music' heard by the space travelers. The astronauts experienced the eerie whistling sounds for almost an hour when the shuttle was on the far side of the moon and therefore, out of radio range from NASA's mission control.
In the transcript of the mission released to the public in 1998, the astronauts discuss the sound intermittently as they go about performing their tasks. Then as they are re-entering the zone where they can communicate with ground control, one of the astronauts asks if they should report it. In response, Stafford expresses his doubts if anyone will even believe them.
But they needn't have worried. When NASA experts listened to the recordings, they attributed the strange whistling sounds to radio interference caused by the two receivers located tens of kilometers apart in the lunar module and the command-service module. According to the US space agency, the whistling sound was a result of the different antennas and communication systems of the radios.
Michael Collins, the Apollo 11 pilot who orbited the moon solo, while Buzz Aldrin and Neil Armstrong were conducting the moon walk also mentions the sounds in his 1974 book 'Carrying the Fire: An Astronaut's Journey.' He says that the only reason he was not spooked upon hearing them was because he had been forewarned by NASA officials. Collins also said that the music stopped as soon as the lunar module landed on the moon.
So why did it take NASA over 40 years to release the digital recording of the eerie music and that too only after it was featured in a recently aired episode of the television series 'NASA's Unexplained Files'? The US Space Agency says they have not been hiding them. In the press release that accompanies the release of the recording, NASA officials state, 'The Apollo 10 audio clips were uploaded in 2012, but the mission's sound recordings have been available at the National Archives (for anyone that wanted to hear them) since the early 1970s.'
Gene Cernan, Apollo 10's pilot who heard the sounds firsthand, also released a statement saying, "I don’t remember that incident exciting me enough to take it seriously. It was probably just radio interference. Had we thought it was something other than that we would have briefed everyone after the flight. We never gave it another thought."
While most people are ready to accept this logical explanation, there are some that believe otherwise. They speculate the music proves the presence of aliens. Among them is Apollo 15 astronaut Al Worden, who thinks the sounds came from a source in outer space. In the episode of 'NASA's Unexplained Files', that discusses the origin of the strange music, the astronaut says, “Logic tells me that if there was something recorded on there, then there was something there."
Alien music or radio interference? You decide!