The Juno space probe, orbiting Jupiter, detected an FM radio signal coming from the moon Ganymede. This is the first time scientists have detected such a signal from this satellite.
“It’s not alien, its origin is natural,” Juno mission expert Patrick Wiggins clarifies. The probe was flying over the polar region of Jupiter, where the magnetic field lines connect to Ganymede, when the radio signal was caught. Scientifically speaking, this is called a “decameter radio emission. Here on Earth, we know it as Wi-Fi and use it every day.
What caused this radio emission? Electrons, not aliens, astophysicists say. Electrons oscillate at a slower rate than they spin, causing the particles to amplify radio waves very quickly. This process is called cyclotron maser instability . Radio-generating electrons can also cause auroras in the far ultraviolet spectrum, a phenomenon also recorded by the Juno cameras.