Voyager 1's plasma wave instrument detected the vibrations of dense interstellar plasma, or ionized gas, from October to November 2012 and April to May 2013. This sound reproduces the amplitude and frequency of the plasma waves as "heard" by Voyager 1.

Voyager: Interstellar Plasma Sounds

Hello, we’re NASA. You may have seen our astronauts, rocket launches, or Mars rovers — but have you heard our sounds? From interviews with astronauts and engineers to stories that take you on a tour of the galaxy, NASA’s audio offerings let you experience the thrill of space exploration without ever leaving Earth.