NASA’s Cassini spacecraft’s high-inclination Grand Finale orbits offered an unprecedented new view of Saturn and its environment. New research from the Grand Finale phase shows a powerful and dynamic interaction of plasma waves moving from the gas giant to its rings and its sixth-largest moon, Enceladus.
The interaction of Saturn and Enceladus is different from the relationship of Earth and its Moon.
Enceladus is immersed in Saturn’s magnetic field and is geologically active, emitting plumes of water vapor that become ionized and fill the environment around Saturn. Our own Moon does not interact in the same way with Earth.
Similar interactions take place between Saturn and its rings, as they are also very dynamic.
“Enceladus is this little generator going around Saturn, and we know it is a continuous source of energy,” said Dr. Ali Sulaiman, a planetary scientist at the University of Iowa.
“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.”
Much like air or water, plasma generates waves to carry energy.
Cassini’s Radio Plasma Wave Science instrument recorded intense plasma waves on September 2, 2017, two weeks before Cassini was deliberately plunged into the atmosphere of Saturn.
Dr. Sulaiman and colleagues then converted these recordings into a ‘whooshing’ audio file that we can hear — in the same way a radio translates electromagnetic waves into music.
“In other words, Cassini detected electromagnetic waves in the audio frequency range — and on the ground, we can amplify and play those signals through a speaker,” they explained.
“The recording time was compressed from 16 minutes to 28.5 seconds.”
The findings were published recently in two papers in the journal Geophysical Research Letters.
Source: Sci News