Looks like you're using an older browser. For the best experience possible, please upgrade your browser or download a modern browser.
We recommend these free browsers: Firefox or Chrome
You must update your Flash version to view videos. http://www.adobe.com/go/getflashplayer
For the optimal Juno experience please install Chrome. Download Chrome. Or continue to explore features of the Juno spacecraft using the links on your left.

News

06.06.18

Nike Air Penny II 333886-100 2 White/Black-Varsity Royal-Black 333886-100 II Men's 13cdc4

Ever since NASA’s Voyager 1 spacecraft flew past Jupiter in March, 1979, scientists have wondered about the origin of Jupiter’s lightning. That encounter confirmed the existence of Jovian lightning, which had been theorized for centuries. But when the venerable explorer hurtled by, the data showed that the lightning-associated radio signals didn’t match the details of the radio signals produced by lightning here at Earth.

In a new paper published in Nature today, scientists from NASA’s Juno mission describe the ways in which lightning on Jupiter is actually analogous to Earth’s lightning. Although, in some ways, the two types of lightning are polar opposites.

“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 of NASA’s Jet Propulsion Laboratory in Pasadena, California, a Juno scientist and lead author of the paper. “But until Juno, all the lightning signals recorded by spacecraft [Voyagers 1 and 2, Galileo, Cassini] were limited to either visual detections or from the kilohertz range of the radio spectrum, despite a search for signals in the megahertz range. Many theories were offered up to explain it, but no one theory could ever get traction as the answer.”

Enter Juno, which has been orbiting Jupiter since July 4, 2016. Among its suite of highly sensitive instruments is the Microwave Radiometer Instrument (MWR), which records emissions from the gas giant across a wide spectrum of frequencies.  

“In the data from our first eight flybys, Juno’s MWR detected 377 lightning discharges,” said Brown. “They were recorded in the megahertz as well as gigahertz range, which is what you can find with terrestrial lightning emissions. We think the reason we are the only ones who can see it is because Juno is flying closer to the lighting than ever before, and we are searching at a radio frequency that passes easily through Jupiter’s ionosphere.”

While the revelation showed how Jupiter lightning is similar to Earth’s, the new paper also notes that where these lightning bolts flash on each planet is actually quite different.

“Jupiter lightning distribution is inside out relative to Earth,” said Brown. “There is a lot of activity near Jupiter’s poles but none near the equator. You can ask anybody who lives in the tropics -- this doesn’t hold true for our planet.”

Why do lightning bolts congregate near the equator on Earth and near the poles on Jupiter? Follow the heat.

Earth’s derives the vast majority of its heat externally from solar radiation, courtesy of our Sun. Because our equator bears the brunt of this sunshine, warm moist air rises (through convection) more freely there, which fuels towering thunderstorms that produce lightning.

Jupiter’s orbit is five times farther from the Sun than Earth’s orbit, which means that the giant planet receives 25 times less sunlight than Earth. But even though Jupiter’s atmosphere derives the majority of its heat from within the planet itself, this doesn’t render the Sun’s rays irrelevant. They do provide some warmth, heating up Jupiter’s equator more than the poles -- just as they heat up Earth. Scientists believe that this heating at Jupiter’s equator is just enough to create stability in the upper atmosphere, inhibiting the rise of warm air from within. The poles, which do not have this upper-level warmth and therefore no atmospheric stability, allow warm gases from Jupiter’s interior to rise, driving convection and therefore creating the ingredients for lightning.

“These findings could help to improve our understanding of the composition, circulation and energy flows on Jupiter,” said Brown. But another question looms, she said. “Even though we see lightning near both poles, why is it mostly recorded at Jupiter’s north pole?”

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. The data set of more than 1,600 signals, collected by Juno’s Waves instrument, is almost 10 times the number recorded by Voyager 1. Juno detected peak rates of four lightning strikes per second (similar to the rates observed in thunderstorms on Earth) which is six times higher than the peak values detected by Voyager 1.

“These discoveries could only happen with Juno,” said Scott Bolton, principal investigator of Juno from the Southwest Research Institute, San Antonio. “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. Also, our microwave and plasma wave instruments are state-of-the-art, allowing us to pick out even weak lightning signals from the cacophony of radio emissions from Jupiter. “

NASA's Juno spacecraft will make its 13th science flyby over Jupiter's mysterious cloud tops on July 16.

NASA's Jet Propulsion Laboratory, Pasadena, California, manages the Juno mission for the principal investigator, Scott Bolton, of the Southwest Research Institute in San Antonio. Juno is part of NASA's New Frontiers Program, which is managed at NASA's Marshall Space Flight Center in Huntsville, Alabama, for NASA's Science Mission Directorate. The Microwave Radiometer instrument (MWR) was built by JPL. The Juno Waves instrument was provided by the University of Iowa. Lockheed Martin Space, Denver, built the spacecraft.
Nike Men's Air Max 90 EZ Running Shoe,Nike Zoom Fly SP Mens Size 9.5 Running Shoe White Sail Bright Crimson AJ9282 106NEW Nike Zoom Rev II TB PROMO AJ7718-605 Pink Breast Cancer Kay Yow RARE Sz 7.5Nike iD Air Force 1 Low Pendleton PND Red Black Wool 10 premium prmNike Mens Air Max 97 OG QS 2018 Metallic Gold Bullet Varsity Red 884421-7002017 Nike Air Jordan 11 Retro Low Barons Sz 11 (0200) 528895-010DS Nike Waffle Racer '17 sz10.5 Black/White/Gum trainer max 90 95 97 876255 002,2007 Nike Air Jordan 1 I ARMED FORCES 325514-231 RETRO HI OG A 11.0 SUPREME SBB,2013 Nike Kobe 8 BHM Black History Month sz 9.5 w/ Box | TRUSTED SELLER!,2017 NIKE AIR MAX 97 OG ‘METALLIC GOLD’ 884421 700 US MENS SZ 6-12,Nike 684722 Mens Air Max 90 Sneakerboot Ice Durable Casual Shoes SneakersNike M2K Tekno John Elliott Summit White Black Orange Men's Dad Shoes AV4789-100,Air Jordan Retro 3 Joker Size 10100% Authentic Brand New Nike Flyknit Racer Men’s SZ 8 Gray/White,NIKE NIKELAB AIR MAX 1 PINNACLE MAX CONTRAST ALL SZ 100% AUTHENTIC 859554-400,AH9046-401 Nike Men's Air Vapormax Thunder Blue/White-Navy size 9.5,Mens Sz 9 Nike Epic React Flyknit Plum Dust/Black-Pink Blast AQ0067-500,NEW 864024 003 Men's Nike SF-AF1 Triple Black Shoe BLACK/BLACK Size 10,Nike SB Zoom Dunk Low Pro Men's Size 12 Legion Green Camo White 854866-331 NIB,NIKE KYRIE 3 AQUA BLUE BLACK KYRIE IRVING MENS BASKETBALL 852395 401 Size 15,Nike Air Jordan 1 One Retro Obsidian Game Royal Blue 554724-412 size 13,Nike Air Max 1 Premium Cool Grey 875844-005Nike Air Max 1 Premium 30th Anniversary Dynamic Berry Purple 875844-500,Nike Air Jordan XII 12 Wolf Grey/University Blue Size 11 Basketball,Nike LeBron XV 15 EP Bright Crimson James Black AQ2364-002 Men Basketball Shoes2017 Nike Air Jordan 31 Low Q54 Quai 54 White Black Sz 11 (4890) 921195-154,Nike Air Force 1 Low 07 QS Size 10-11 All Over Logo Red AH8462 600Nike Air Max 90 Sneakerboot WHEAT FLAX HAYSTACK 684714-700 sz 10 WINTER BOOTMens Nike Air Max 270 Flyknit AO1023-101 White/Black Brand New Size 9,Nike Fly Knit Trainer Mens 12 Sneakers Shoes Red Electric Green White Swoosh,
NIKE KOBE AD A.D ID. BLACK-VOLT GREEN "MAMBA" SZ 12.5 [AQ4789-991],

Members of the media, please contact:

D.C. Agle
Juno Media Relations Representative
NASA's Jet Propulsion Laboratory
Dwayne Brown
NASA Public Affairs Officer
NASA Headquarters

Where is Juno now?

Visualize Juno’s journey through space and get up-to-date data sets using NASA's Eyes on the Solar System 3D interactive.