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Juno Scientists Solve Mysteries of Jupiter's Lightning | Planetary Science, Space Exploration

Juno Scientists Solve Mysteries of Jupiter's Lightning | Planetary Science, Space Exploration

Since 1979, when the NASA's Voyager 1 spacecraft flew past Jupiter, scientists were in wonder about the origin of Jupiter's lightning, Jovian lightning. For nearly 40 years the question of the differences of lightning on the planets remained unsolved.

Some of Juno's accomplishments include offering humanity's first up-close view of Jupiter's Great Red Spot, stating that the planet's atmosphere has features unlike anything else encountered in the solar system, and that the Great Red Spot storm has been shrinking for years but that as it shrinks it grows taller.

This longer orbit means the Juno probe requires more time to collect the amount of data NASA aimed to acquire and process.

That's a lot to digest, so let's break it down a bit: All the tools on previous spacecraft that tried to listen in to Jupiter's lightning didn't hear the kinds of radio signals that are produced by lightning on Earth.

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. The dataset of in excess of 1,600 signs, gathered by Juno's Waves instrument, is right around 10 times the number recorded by Voyager 1.

"We succeeded in collecting the largest set of lightning detections known up to now", Kolmašová told Gizmodo.

"Our unique orbit allows our spacecraft to fly closer to Jupiter than any other spacecraft in history, so the signal strength of what the planet is radiating out is a thousand times stronger", Scott Bolton, principal investigator of Juno from the Southwest Research Institute, San Antonio, said. And they detected peak rates of four lightning strikes per second, similar to rates observed in Earth thunderstorms.

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




The findings, published in Nature Wednesday, also suggest some differences in Jupiter's lightning compared to Earth's - mainly the location. By that point, radiation damage to the craft is expected to be severe and it will be ordered to make a controlled entry into the Jovian atmosphere, where it will burn up. The majority of Jupiter's zaps take place near the poles. "You can ask anybody who lives in the tropics-this doesn't hold true for our planet", Mr Brown added. This is much higher than Voyager previously detected and similar to rates found on Earth. "On Earth, thunderstorms tend to cluster around low latitudes, and on Jupiter, it's the other way around".

At the same time, it turns out that Jovian lightning is more frequent in the northern hemisphere than in the southern one, although scientists don't have an explanation yet as to why this happens.

"Jupiter lightning distribution is inside out relative to Earth".

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

Heat drives lightning, and the sun's rays cause Earth's equator to heat up more than the poles.

The poles don't have this source of warmth and stability, leaving their upper atmosphere untamed and stormy.

Juno has made all of this research possible. This is far more than earlier spacecraft could detect.