Category Archives: Juno

Juno Solves a Mystery

The Juno has helped solve the mystery of Jupiter’s lightning. PLUS, NASA has announced the Juno mission has been re-planned adding 41 months in orbit. That change will enable the spacecraft to collect more data, the orbits are 53 days instead of the planned 14 so collecting the necessary data takes longer.

So great news there and now about the lightning (artist concept above from NASA/JPL-Caltech/SwRI/JunoCam(:

NASA: 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. “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.

The Great Red Spot

Beautiful work! Check this and other great submissions to the JunoCam site, not to mention the original images from Juno for anybody who wants to try their hands at processing.

Original caption:

This image of Jupiter’s iconic Great Red Spot and surrounding turbulent zones was captured by NASA’s Juno spacecraft.

The color-enhanced image is a combination of three separate images taken on April 1 between 3:09 a.m. PDT (6:09 a.m. EDT) and 3:24 a.m. PDT (6:24 a.m. EDT), as Juno performed its 12th close flyby of Jupiter. At the time the images were taken, the spacecraft was 15,379 miles (24,749 kilometers) to 30,633 miles (49,299 kilometers) from the tops of the clouds of the planet at a southern latitude spanning 43.2 to 62.1 degrees.

Citizen scientists Gerald Eichstädt and Seán Doran processed this image using data from the JunoCam imager.

JunoCam’s raw images are available at www.missionjuno.swri.edu/junocam for the public to peruse and process into image products.

Image credit and a hearty well-done to: NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstadt/Sean Doran

Jupiter’s Storm Clouds

The more I look at this image the more I like it and it is little wonder this was NASA’s Image of the Day.

This was a submission on the JunoCam site. Be sure to check that site out too; maybe even download some images and see how you do.

This particular piece of work was done by citizen scientists Matt Brealey and Gustavo B C. Well done.

The original caption from NASA: This image captures a close-up view of a storm with bright cloud tops in the northern hemisphere of Jupiter.

NASA’s Juno spacecraft took this color-enhanced image on Feb. 7 at 5:38 a.m. PST (8:38 a.m. EST) during its 11th close flyby of the gas giant planet. At the time, the spacecraft was 7,578 miles (12,195 kilometers) from the tops of Jupiter’s clouds at 49.2 degrees north latitude.

Citizen scientist Matt Brealey processed the image using data from the JunoCam imager. Citizen scientist Gustavo B C then adjusted colors and embossed Matt Brealey’s processing of this storm.

mage credits: NASA/JPL-Caltech/SwRI/MSSS/Matt Brealey/Gustavo B C

Jupiter’s North Pole

NASA’s caption:  In this composite image, derived from data collected by the Jovian Infrared Auroral Mapper (JIRAM) instrument aboard NASA’s Juno mission to Jupiter, shows the central cyclone at the planet’s north pole and the eight cyclones that encircle it. JIRAM collects data in infrared, and the colors in this composite represent radiant heat: the yellow (thinner) clouds are about 9 degrees Fahrenheit (-13°Celsius) in brightness temperature and the dark red (thickest) are around -181 degrees Fahrenheit (83°Celsius).

More information about Juno is online at http://www.nasa.gov/juno and http://missionjuno.swri.edu.

Credits: NASA/JPL-Caltech/SwRI/ASI/INAF/JIRAM

There’s more!  We are starting to get papers released and the data is being turned into results.

NASA has a nice release located here, the release also includes abstracts of some of the newly published papers.  Bravo NASA!

Here they are:

The measurement of Jupiter’s asymmetric gravity field:

http://nature.com/articles/doi:10.1038/nature25776

Jupiter’s atmospheric jet-streams extending thousands of kilometers deep:

http://nature.com/articles/doi:10.1038/nature25793

A suppression of differential rotation in Jupiter’s deep interior:

http://nature.com/articles/doi:10.1038/nature25775

Clusters of Cyclones Encircling Jupiter’s Poles:

http://nature.com/articles/doi:10.1038/nature25491

 

Jupiter’s South Pole

I think this is my new favorite JunoCam image so far. The image above was from PeriJove 11 and the processing was masterfully done by Kevin M Gill and uploaded to the JunoCam site.

You can click the image above for a larger version although I recommend checking out this one at the JunoCam link to South Pole by Kevin Gill to see the wonderful detail in the full sized version.

I also realize I have a “new favorite” quite often, you might find another.  Here’s a link to this and other submissions on JunoCam

Want to give processing JunoCam images? It’s easy to participate;  just go to the JunoCam site and they will tell you how.

Credit : NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill © CC BY

The Best So Far

Wow! What a great job by Kevin Gill the citizen scientist who produced this beautiful image of Jupiter using data from the JunoCam aboard the Juno spacecraft. I think this is the best JunoCam submission so far, really good. You can click the image above for a larger view and go to the JunoCam site to see the full sized version and it is worth it – seriously have a look.  Happily, you might disagree about this being the best so far; after all there ARE quite a few to choose from.

Don’t forget — YOU can also try your hand at working with the JunoCam data to create images like this.  In fact NASA has gone out of their way to make it easy,  When you have something you like you can even upload them to share on the NASA site.  How?  Easy, just go to the JunoCam Image Processing Gallery and click on the Submissions Guidelines link.

Here’s the original caption:

Colorful swirling cloud belts dominate Jupiter’s southern hemisphere in this image captured by NASA’s Juno spacecraft.

Jupiter appears in this color-enhanced image as a tapestry of vibrant cloud bands and storms. The dark region in the far left is called the South Temperate Belt. Intersecting the belt is a ghost-like feature of slithering white clouds. This is the largest feature in Jupiter’s low latitudes that’s a cyclone (rotating with clockwise motion).

This image was taken on Dec. 16, 2017 at 10:12 PST (1:12 p.m. EST), as Juno performed its tenth close flyby of Jupiter. At the time the image was taken, the spacecraft was about 8,453 miles (13,604 kilometers) from the tops of the clouds of the planet at a latitude of 27.9 degrees south.

The spatial scale in this image is 5.6 miles/pixel (9.1 kilometers/pixel).

Citizen scientist Kevin M. Gill processed this image using data from the JunoCam imager.

JunoCam’s raw images are available at www.missionjuno.swri.edu/junocam for the public to peruse and process into image products.

More information about Juno is online at http://www.nasa.gov/juno and http://missionjuno.swri.edu.

NASA’s Jet Propulsion Laboratory manages the Juno mission for the principal investigator, Scott Bolton, of 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. Lockheed Martin Space Systems, Denver, built the spacecraft. Caltech in Pasadena, California, manages JPL for NASA.

Image Credit: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill

Near Jupiter’s Cloudtops

The Juno spacecraft was only 18,906 km / 11,747 miles above the cloud tops of Jupiter – pretty bold.

Here’s the original caption: See Jovian clouds in striking shades of blue in this new view taken by NASA’s Juno spacecraft.

The Juno spacecraft captured this image when the spacecraft was only 11,747 miles (18,906 kilometers) from the tops of Jupiter’s clouds — that’s roughly as far as the distance between New York City and Perth, Australia. The color-enhanced image, which captures a cloud system in Jupiter’s northern hemisphere, was taken on Oct. 24, 2017 at 10:24 a.m. PDT (1:24 p.m. EDT) when Juno was at a latitude of 57.57 degrees (nearly three-fifths of the way from Jupiter’s equator to its north pole) and performing its ninth close flyby of the gas giant planet.

The spatial scale in this image is 7.75 miles/pixel (12.5 kilometers/pixel).

Because of the Juno-Jupiter-Sun angle when the spacecraft captured this image, the higher-altitude clouds can be seen casting shadows on their surroundings. The behavior is most easily observable in the whitest regions in the image, but also in a few isolated spots in both the bottom and right areas of the image.

Citizen scientists Gerald Eichstädt and Seán Doran processed this image using data from the JunoCam imager.

JunoCam’s raw images are available at www.missionjuno.swri.edu/junocam for the public to peruse and process into image products.

Great job! Credits: Gerald Eichstädt / Seán Doran /JUNO

Moon Shadow

What a nice image of a moon shadow on Jupiter.  Wanted to show this and hopefully I can in-between internet and power outages – it’s really windy and believe it or not most leaves are STILL on the trees.

Nice processing work on the Juno image from Gerald Eichstädt and Seán Doran (see below).  Image credit: NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstädt and Seán Doran

More about Amalthea from NASA.  Click the image below for a larger version.

From NASA – Jupiter’s moon Amalthea casts a shadow on the gas giant planet in this image captured by NASA’s Juno spacecraft. The elongated shape of the shadow is a result of both the location of the moon with relation to Jupiter in this image as well as the irregular shape of the moon itself.

The image was taken on Sept. 1, 2017 at 2:46 p.m. PDT (5:46 p.m. EDT), as Juno performed its eighth close flyby of Jupiter. At the time the image was taken, the spacecraft was 2,397 miles (3,858 kilometers) from the tops of the clouds of the planet at a latitude of 17.6 degrees.

Citizen scientists Gerald Eichstädt and Seán Doran processed this image using data from the JunoCam imager. The image has been rotated so that the top of the image is actually the equatorial regions while the bottom of the image is of the northern polar regions of the planet.

JunoCam’s raw images are available at www.missionjuno.swri.edu/junocam for the public to peruse and process into image products.

 

Io and Europa

Another really great JunoCam image; this one processed by citizen scientist Roman Tkachenko.

NASA – This color-enhanced image of Jupiter and two of its largest moons — Io and Europa — was captured by NASA’s Juno spacecraft as it performed its eighth flyby of the gas giant planet.

The image was taken on Sept. 1, 2017 at 3:14 p.m. PDT (6:14 p.m. EDT). At the time the image was taken, the spacecraft was about 17,098 miles (27,516 kilometers) from the tops of the clouds of the planet at a latitude of minus 49.372 degrees.

Closer to the planet, the Galilean moon of Io can be seen at an altitude of 298,880 miles (481,000 kilometers) and at a spatial scale of 201 miles (324 kilometers) per pixel. In the distance (to the left), another one of Jupiter’s Galilean moons, Europa, is visible at an altitude of 453,601 miles (730,000 kilometers) and at a spatial scale of 305 miles (492 kilometers) per pixel.

Image: NASA/JPL-Caltech/SwRI/MSSS/Roman Tkachenko