Analysis of the radio spectrum indicated that one source of these transmissions were lightning bolts arcing through the Jovian atmosphere, a billion times more powerful than those on Earth.
On Earth, radio waves associated with lightning are in the megahertz range.
These radio waves Voyager detected were due to the electrical currents within lightings that generate the so-called "sferics" (broad array of radio signals).
The other study, published in the journal Nature, unveiled that lighting on Jupiter produces not only kilohertz emissions, the singular radio range detected by Voyager 1 almost four decades ago, but also gigahertz radio waves, just like lightning on Earth. Now, reports Charles Q. Choi at Space.com, the Juno spacecraft has taken its own measurements and found that lightning on Jupiter is not as odd as we once thought.
In a second Juno lightning paper published today in Nature Astronomy, Ivana Kolmašová of the Czech Academy of Sciences, Prague, and colleagues, present the largest database of lightning-generated low-frequency radio emissions around Jupiter (whistlers) to date.
It's a longstanding mystery that could only have been solved with Juno.
"Many theories were offered up to explain it, but no one theory could ever get traction as the answer", Brown said of the problem.
Researchers detected more than 1,600 instances of lightning on Jupiter gathered via a phenomenon called "whistlers".
Data from everyone's favourite Jupiter probe has revealed that, contrary to previous measurements, the gas giant's lightning does occur in megahertz frequencies, and occurs much more frequently than thought - but it also seems to be localised to the planet's poles.
Scientists believe Juno was able to pick up the megahertz signatures because its flyby put it closer to the lightning than any spacecraft before it.
The data set of more than 1,600 signals, collected by Juno's Waves instrument, is nearly 10 times the number recorded by Voyager 1. The sun's rays that warm our own planet hit the equator first, and it is the warm, humid air rising at this band that drives its lightning. In any case, despite the fact that Jupiter's atmosphere infers the more of its heat within the planet itself, this doesn't render the Sun's beam irrelevant.
But there's one more way lightning on Jupiter is similar to Earth lightning. This varying radio frequency suggests that the lightning from the two planets are wildly different.
The Juno data also has shed light on why lightning tends to occur only at high latitudes on Jupiter while they are common in the equatorial tropics on Earth.
"These findings could help to improve our understanding of the composition, circulation and energy flows on Jupiter", says Brown.
Jupiter's poles, which aren't warmed by the Sun, have a less stable atmosphere, according to NASA, which allows warm gases to rise and create the recipe needed to produce lightning. NASA just re-enlisted Juno, adding another 41 months to its mission.
"This is great news for planetary exploration as well as for the Juno team", Juno principal investigator Scott Bolton, from the Southwest Research Institute in San Antonio, said in the same statement.