Recently unearthed recordings made by NASA of the journey, which took the Apollo 10 capsule around the far side of the moon, show the astronauts reacting with surprise and confusion to an unearthly howling noise in their headsets.

The sound began once the capsule was on an hour-long trip around the far side of the moon, out of the range of any Earth broadcast. At one point the baffled astronauts can be heard discussing whether they should tell NASA command or not.


'You hear that? That whistling sound? Whooooooooo!' one of them says.

Another astronaut says he can: 'It sounds like, you know, outer space-type music.' 

'Well, that sure is weird music,' his companion agrees. 

[link to www.dailymail.co.uk]