A statement from the space agency said: “Soaring to the depths of our universe, gallant spacecraft roam the cosmos, snapping images of celestial wonders. Some spacecraft have instruments capable of capturing radio emissions. When scientists convert these to sound waves, the results are eerie to hear.
“In time for Halloween, we've put together a compilation of elusive "sounds" of howling planets and whistling helium that is sure to make your skin crawl.”
A selection of the recordings are described below.
The audio files were taken from planets, a comet and plasma waves. The first, Juno Crossing Jupiter’s Bow Shock, is the sound of NASA’s spacecraft moving across the gas giant’s magnetic field. The whistling sound suddenly turns into a deeper boom as Juno passes from an environment dominated by solar wind into Jupiter’s magnetosphere.
Chorus Radio Waves within Earth's Atmosphere is the sound of plasma waves rolling through space. The waves are electric and magnetic fields moving through the ions and electrons that compose the plasma. The interaction causes the rhythmic sound on the recording.
Saturn’s Radio Emissions were recorded with the Cassini spacecraft, which recently plunged into the planet’s atmosphere bringing its long mission to a close. Saturn is a source of intense radio emissions that are related to the planet’s auroras near its poles. The sounds recorded are very similar to the radio emissions from Earth’s auroras.
Lightning on Jupiter was recorded by the Voyager spacecraft. The whistling emission is the sound of lightning moving away from the planet and into the magnetized plasma above. As the waves move into the plasma, higher frequency ones move faster, meaning these get picked up first. The difference between the high and low-frequency waves produces the whistling sound.
Stardust: Passing Comet Tempel 1 is a recording of a comet flyby in 2011. NASA’s Stardust spacecraft was bombarded with dust particles from the comet and this is what can be heard in the recording. Over 11 minutes, the spacecraft was hit by around 5,000 bits of rock, ice and dust.