Our planet is absolutely buzzing with audio transmissions.
Look around your room now. Your phone, your television, FM radio, satellite TV – there are broadcasts everywhere.
Now imagine you’re in the one spot where all of that is blocked out - the dark side of the Moon.
There, you’ll hear nothing from Earth. In fact, NASA astronauts fear being there because they have no communication with their control team when they pass behind the Moon.
But new transcripts and audio files released by NASA - being broadcast as part of a new documentary series - reveal that astronauts onboard the Apollo 10 mission reported hearing eerie, strange "outer space-type music".
NASA’s transcripts document a conversation when the astronauts had returned to Earth.
"You hear that? That whistling sound? Whoooooo!"
Alien chasers and conspiracy theorists have responded with excitement, but fellow astronauts have come up with a far more simple and boring explanation for the noise.
Apollo 11’s Michael Collins has also flown around the Moon.
In his book Carrying the Fire, Collins spoke of an eerie woo-woo sound in his headset which was explained to him as interference between radios being used by the Apollo mission spacecraft.
Although the transcripts and recordings are now declassified, NASA has not commented on a possible cause.
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