More than four decades ago, when Apollo 10 astronauts were preparing for the first-ever lunar landing by man, they reportedly heard a mysterious sound when their spaceship passed the dark side of the moon.
The “outer spacey” music stumped the astronauts, who could not figure out where the sound was coming from. Since, the mission was akin to a dress rehearsal for Neil Armstrong and Buzz Aldrin’s famous landing two months later, NASA classified the tapes and locked them from the prying eyes of the common masses.
In 2008, the U.S. space agency released the transcripts of the discussion that took place between the astronauts. But the actual sounds have only just been made public, all for an episode of the new Science Channel series “NASA's Unexplained Files.”
Apparently, when Apollo 10 entered into lunar orbit and got within 5,000 feet of the surface of the moon, the craft went out of radio contact with Earth for at least 60 minutes. The three astronauts, Eugene Cernan, John Young and Tom Stafford, were not expecting to hear anything on their instruments, which is why the mysterious whistling sounds left them baffled.
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“You hear that? That whistling sound? Whoooooo,” said Cernan on the recording. “That sure is weird music.”
It was so unexpected and bizarre that the team even debated if they should mention it to their superiors at NASA, fearing scrutiny about their mental health their future in space flight.
There are a number of plausible theories as to what the astronauts heard. In fact, a NASA technician believes the strange whistling was simply radio interference from within the spacecraft. But there also several conspiracy theorists who believe the sounds came from alien life forces in the galaxy.
Check out the early transcripts released by the NASA below: