This could prove useful for Greatest K&L work . . .
Voyager spacecraft visited the outer planets and some moons.
It took recordings of electromagnetic waves being emitted from these planetary bodies.
Those recordings in the frequency of human hearing were converted to sound.
Symphonies of the Planets:
If you go to ITunes as it suggests at the end, you can buy the album where each planetary body is given about 30 minutes rather than this sampler here.