The strange signal is understood to have come from Ganymede and was detected by NASA’s Juno space probe.
Juno’s mission is to study the planet Jupiter and understand how the planet and its 79 moons were formed.
NASA said the signal lasted just five seconds and the discovery marks the first time a detection has come from the moon.
At the time of detection, Juno was travelling across the polar region of Jupiter, where magnetic field lines connect to Ganymede at a speed of 111,847mph.
Sadly for alien believers, NASA ruled out any extraterrestrial behaviour and put the discovery down to electrons.
NASA ambassador Patrick Wiggins, from Utah, told news outlet KTVX: “It’s not E.T.
“It’s more of a natural function.”
According to the publication, the signal was most likely caused by electrons oscillating at a lower rate than at which they spin, amplifying radio waves.
The same process was also reportedly behind similar signals coming from Jupiter as detected by Juno in 2017.
A year later, scientists revealed they had observed “extraordinary” electromagnetic waves coming from the Ganymede moon.
The waves were spotted by potted by NASA’s Galileo Probe spacecraft, which was tasked with the mission of observing Jupiter’s wave environment.
At the time, lead author of the study, Yuri Shprits, told the Independent it was a “surprising” and “puzzling observation.”
She said: “It’s a really surprising and puzzling observation showing that a moon with a magnetic field can create such a tremendous intensification in the power of waves.”