Freesound Forums

http://doubtfulnews.com/?s=strange+sounds

I have to admit I watched dozens of these strange noises in the sky videos, both fascinated and skeptical. This little "explaination" is definately my favourite and not really an explaination at all, but you can hear some amazing sounds from the nasa website.
http://www.youtube.com/watch?v=kJpXfLjs3yw

If we are including outer-space (NASA) how about the sound of a pulsar ...

http://www.jb.man.ac.uk/~pulsar/Education/Sounds/vela.au

[ image ... http://en.wikipedia.org/wiki/Vela_Pulsar ]

Cool! I found this gem whilst looking for strange sounds

http://www.youtube.com/watch?v=u37Alptld-c

but seriously . . . the 5 "most mysterious sounds recorded"

http://www.youtube.com/watch?v=-c7hCWwTlrY