LIEGE, Belgium, March 19 (UPI) -- European scientists have observed unexpected luminous spots on Jupiter caused by its moon, Io, similar to Earth's Northern Lights.
From previous studies, researchers knew the Io footprint to be a bright spot that is often followed by other auroral spots. Those spots are typically located downstream relative to a flow of charged particles around the giant planet, scientists said.
In the new research, a team of planetologists from Belgium and Germany have discovered Io's footprint can include a faint spot unexpectedly upstream of the main spot.
"Previously, we only observed downstream spots, but only half of the configurations of Io in the Jovian magnetic field had been studied," said Bertrand Bonfond of the University of Liege in Belgium. "Now we have the complete picture. The results are surprising because no theory predicted upstream spots."
Like a rock in a stream, Io obstructs the flow of charged particles, or plasma, around Jupiter, the scientists said. As the moon disrupts the flow, it generates powerful plasma waves that blast electrons into Jupiter's atmosphere, creating the auroral spots.
The research appears in the journal Geophysical Research Letters.