space oddity

While orbiting around the dark-side of the Moon, in the communications shadow cast by the intervening planetary body, the crew of Apollo 10 debated on whether to disclose to Mission Control they had picked up on the eerie whistling sounds of the music of the celestial spheres, for fear they might be grounded from future missions.
The entire affair was not suppressed exactly but went mostly unnoticed until 2008 after it came out in a memoir and the same bursts of errant sounds were heard on successive lunar visits and by other space probes, and technicians could be reasonably certain that the noise was some sort of feedback or interference or naturally occurring report—and not extra-terrestrial transmissions. The audio, however, had not been made publicly available until now, so one can judge for one’s self—though it smacks of a promotion-stunt rather than any kind of government-sanctioned UFO cover-up. Even if the explanation is a mundane one, it would have been quite jarring to encounter in the silence of the void.