NASA Solves The Mystery Of Jupiter's Lightning


"Given the very pronounced differences in the atmospheres between Jupiter and Earth", said William Kurth, the leading author of the second study, the similarities between lightning on Jupiter and the lightning storms on Earth are stunning.

"Until Juno, all the lightning signals recorded by spacecraft were limited to either visual detections or from the kilohertz range of the radio spectrum, despite a search for signals in the megahertz range", Mr Brown explained.

"No matter what planet you're on, lightning bolts act like radio transmitters - sending out radio waves when they flash across a sky", Shannon Brown of NASA's Jet Propulsion Laboratory and the lead author of the latest work said in a statement.

There also seems to be more lightning in Jupiter's northern hemisphere compared to its southern side.

This discovery was backed up in the second article, published by a team of scientists of the Academy of Sciences of the Czech Republic, which presented the most famous record collection of lightning with a giant planet.

Lightning bolts in Jupiter's turbulent atmosphere have long puzzled scientists because they did not appear to generate the same high-energy radio emissions that accompany discharges in Earth's atmosphere.

They do provide some warmth, heating up Jupiter's equator more than the poles - just as they heat up Earth. Jupiter's recorded lightning strikes are typically smaller than on Earth, but not all the time, with most bursts have a frequency of about 600 megahertz, but which have the potential to reach gigahertz levels like the bolts seen on Earth.

In a pair of studies published on June 6, scientists from the Juno mission describe the radio emissions coming from Jovian lightning - dubbed "whistlers" on account of their descending whistling pitch, which sounds a lot like a falling bomb - as well as the novel frequencies at which they were picked up by the spacecraft still in orbit around the gas giant. "Even though we see lightning near both poles, why is it mostly recorded at Jupiter's north pole?". This is much higher than Voyager previously detected and similar to rates found on Earth. The spacecraft landed on the surface of Jupiter on 4 July 2016. Heat rising from the planet creates roiling convection currents that lead to storms and lightning.

Heat drives lightning, and the sun's rays cause Earth's equator to heat up more than the poles. The spacecraft came nearly 50 times closer to the planet than Voyager 1 ever did, flying "closer to Jupiter than any other spacecraft in history", states Juno's principal investigator Scott Bolton from the Southwest Research Institute in San Antonio, who was involved in both studies.

Lightning flashes on Jupiter in this artist's impression.

Brown said "These findings could help to improve our understanding of the composition, circulation and energy flows on Jupiter".

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.

The U.S. space agency must be impressed with the last two years of new findings because it announced it was extending the Juno mission through July 2021.

Juno has made all of this research possible.

"To really understand Jupiter, you need to map it", said Scott Bolton, principal investigator and associate vice president at the Southwest Research Institute.