Data transmitted back to Earth by Cassini before it made its final swan dive into Saturn has uncovered new information about the way Saturn interacts with its icy moon Enceladus. NASA has released audio and information about the electromagnetic energy flowing between the bodies and it is really quite a bit spooky. In fact, it sounds exactly like what one would think "space sound transmissions" would sound like.
Sweeping, hollow wave like sounds, punctuated with a steady, fast-moving beat make it sound like the background score of a gripping horror film or like a scary alien radio transmission. NASA has, however, explained the sounds as a "powerful and dynamic interaction of plasma waves moving from Saturn to its rings and its moon Enceladus."
This is the first time that waves that travel on magnetic fields on lines directly connecting Saturn with Enceladus have been detected. The field is like a direct circuit between the planet and its Moon where energy flows back and forth, making strange sounds along the way.
Enceladus is of particular interest now because it is one of the candidates inside the Solar System that could actually host life. The space agency recently revealed that there are complex organic molecules in Enceladus' inner water ocean world. This comes from data that Cassini collected based on the ice that it regularly spews into Saturn's rings.
Researchers studying the Cassini data converted the recordings of plasma waves into an audio file that humans can hear in a process similar to the way radios translate electromagnetic waves into music that can be heard, reports NASA. Cassini, through its onboard instruments, detected electromagnetic waves that were within the audio frequency range going back and forth between the two bodies. On Earth, it is possible to simply amplify and replay those signals as music. The audio clip was also compressed from a file 16 minutes long to about 28.5 seconds, explains the report.
It is common knowledge that sound cannot travel through a vacuum, so how did NASA get a sound file? Air or water can generate waves to carry energy, and so does plasma—the fourth state of matter— explains the release. Cassini's Radio Plasma Wave Science (RPWS) instrument simply recorded the intense plasma waves during one of its close flybys between Saturn and its rings.
Ali Sulaiman, a member of the RPWS team and lead author of the paper, explained how, "Enceladus is this little generator going around Saturn, and we know it is a continuous source of energy.
"Now we find that Saturn responds by launching signals in the form of plasma waves, through the circuit of magnetic field lines connecting it to Enceladus hundreds of thousands of miles away."
The study was first published by the American Geophysical Union.