NASA’s Voyager 1 spacecraft captured these sounds of interstellar space as it travels farther than anyone, or anything, in history. The soundtrack reproduces the amplitude and frequency of the plasma waves as “heard” by Voyager 1. The waves detected by the instrument antennas can be simply amplified and played through a speaker. These frequencies are within the range heard by human ears.
These sounds were recorded by the Cluster II satellite on the 9th of July 2001 using a Long Wave Radio receiver. Through a process of transposition and filtering the signal (which are naturally outside of the range of human hearing) the tones become audible.