Astronomers have been busy dissecting data captured during Cassini’s Grand Finale mission and have come across a completely new interaction between Saturn and its moon Enceladus.
According to Science Alert, by utilizing the Radio Plasma Wave Science tool (RPWS), researchers have been able to hear plasma waves traveling in between the two bodies, proving that these waves are able to easily navigate the magnetic field lines between Enceladus and Saturn.
The fresh evidence of the interaction between Saturn and its moon was fortunately captured just two weeks before Cassini made its final plunge, and University of Iowa planetary scientist Ali Salaiman noted that astronomers now know that when Enceladus pushes out energy, Saturn responds in kind by sending plasma waves to this moon.
“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.”
While we know that there is no “sound” as such traveling between Saturn and Enceladus since that would require air, radio waves can and do travel through space, and we are able to pick up plasma waves from probes like Cassini.
Once captured, scientists are then able to turn these plasma waves into audio, and in the case of the interaction between Saturn and Enceladus they took 16.1 minutes of an audio recording and sped it up so that it lasted just 28.5 seconds.
The guttural hissing sounds that were captured between Saturn and Enceladus are just as eerie as those that you might hear emanating from an aurora, which is perhaps why they have been given the name of an auroral hiss. And while there have been auroral hiss recordings taken of this moon, this marks the first occasion of any sounds so close to Saturn itself.
The interaction between Enceladus and Saturn differs markedly from the relationship that Earth shares with its moon, with one of Saturn’s rings created from a geyser found on Enceladus, showing that ours is a much more mundane relationship.
The audio recording of the plasma waves was taken on September 7, 2017, and the Cassini probe held 12 different instruments on it with which to study Saturn. Studying plasma and radio waves can be a great help when it comes to understanding more about the relationship a planet like Saturn has with its rings and moons.
Interestingly, it is through studies like these that we learned that the auroras on Saturn send off radio waves that are extremely similar to the frequency that we use here on Earth for AM radio stations.
The study conducted on the unique relationship and interaction that has been shown between Saturn and Enceladus has been published in Geophysical Research Letters.