Best Jupiter Images From Juno … So Far

Jupiter as seen by the Juno spacecraft during the Perijove 5 pass on March 27, 2017. Processed using raw data. Credit: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill.

The original plans for the Juno mission to Jupiter didn’t include a color camera. You don’t need color images when the mission’s main goals are to map Jupiter’s magnetic and gravity fields, determine the planet’s internal composition, and explore the magnetosphere.

But a camera was added to the manifest, and the incredible images from the JunoCam have been grabbing the spotlight.

As an instrument where students and the public can choose the targets, JunoCam is a “public outreach” camera, meant to educate and captivate everyday people.

“The whole endeavor of JunoCam was to get the public to participate in a meaningful way,” said Candy Hansen, Juno co-investigator at the Planetary Science Institute in Tucson, Arizona, speaking at a press conference last week to showcase Juno’s science and images.

And participate they have. Hundreds of ‘amateur’ image processing enthusiasts have been processing raw data from the JunoCam, turning them into stunning images, many reminiscent of a swirling Van Gogh ‘starry night’ or a cloudscape by Monet.

The swirling cloudtops of Jupiter, as seen by Juno during Perijove 5 on March 27, 2017. Credit: NASA/JPL-Caltech/SwRI/MSSS/Sophia Nasr.

“The contributions of the amateurs are essential,” Hansen said. “I cannot overstate how important the contributions are. We don’t have a way to plan our data without the contributions of the amateur astronomers. We don’t have a big image processing team, so we are completely relying on the help of our citizen scientists.”

Jupiter as seen by Juno during Perijove 6 in May, 2017. Credit: NASA/SwRI/MSSS/Gerald Eichstädt / Seán Doran.

Click on this image to have access to a 125 Megapixel upscaled print portrait.

Featured here are images processed by Seán Doran, Sophia Nasr, Kevin Gill and Jason Major. Like hundreds of others around the world, they anxiously await for data to arrive to Earth, where it is uploaded to the public Juno website. Then they set to work to turn the data into images.

“What I find the most phenomenal of all is that this takes real work,” Hansen said. “When you download a JunoCam image and process it, it’s not something you do in five minutes. The pictures that we get that people upload back onto our site, they’ve invested hours and hours of their own time, and then generously returned that to us.”

This video shows Juno’s trajectory from Perijove 6, and is based on work by Gerald Eichstädt, compiled and edited by Seán Doran. “This is real imagery projected along orbit trajectory,” Doran explained on Twitter.

Many of the images are shared on social media, but you can see the entire gallery of processed JunoCam images here. The Planetary Society also has a wonderful gallery of images processed by people around the world.

Intricate swirls on Jupiter Jupiter, from Juno’s Perijove 6 pass on May 19, 2017. Credit:
NASA/JPL-Caltech/SwRI /MSSS/Kevin M. Gill.
Details of Jupiter’s swirling gas clouds, as seen by Juno during the Perijove 6 pass in May, 2017. Credit:
NASA / SwRI / MSSS / Gerald Eichstädt / Seán Doran.

JunoCam was built by Malin Space Science Systems, which has cameras on previous missions like the Curiosity Mars Rover, the Mars Global Surveyor and the Mars Color Imager on the Mars Reconnaissance Orbiter. To withstand the harsh radiation environment at Jupiter, the camera required special protection and a reinforced lens.

Whenever new images arrive, many of us feel exactly like editing enthusiast Björn Jónsson:

Even the science team has expressed their amazement at these images.

“Jupiter looks different than what we expected,” said Scott Bolton, Juno’s principal investigator at the Southwest Research Institute. “Jupiter from the poles doesn’t look anything like it does from the equator. And the fact the north and south pole don’t look like each other, makes us wonder if the storms are stable, if they going to stay that way for years and years like the the Great Red Spot. Only time will tell us what is true.”

Read our article about the science findings from Juno.

A sequence of images of Jupiter from Juno’s Perijove 6 pass during May, 2017. Credit:
NASA / SwRI / MSSS / Gerald Eichstädt / Seán Doran.

Part of what makes these images so stunning is that Juno is closer to Jupiter than any previous spacecraft.

“Juno has an elliptical orbit that brings it between the inner edges of Jupiter’s radiation belt and the planet, passing only 5,000 km above the cloud tops,” Juno Project Manager Rick Nybakken told me in my book ‘Incredible Stories From Space: A Behind-the-Scenes Look at the Missions Changing Our View of the Cosmos.’ “This close proximity to Jupiter is unprecedented, as no other mission has conducted their science mission this close to the planet. We’re right on top of Jupiter, so to speak.”

Juno engineers designed the mission to enable the use of solar panels, which prior to Juno, have never been used on a spacecraft going so far from the Sun. Juno orbits Jupiter in a way that the solar panels are always pointed towards the Sun and the spacecraft never goes behind the planet. Juno’s orbital design not only enabled an historic solar-powered mission, it also established Juno’s unique science orbit.

White oval on Jupiter during Juno’s Perijove 4 pass on February 2, 2017. Processed from raw data. Credit: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill.
Uncalibrated, processed raw image from Juno’s Perijove 6 pass of Jupiter on May 19, 2017. Credit: NASA/SwRI/MSSS/Jason Major.

Juno spacecraft launched from Cape Canaveral on August 5, 2011. After traveling five years and 1.7 billion miles Juno arrived in orbit at Jupiter on July 4, 2016. The mission will last until at least February 2018, making 11 science orbits around Jupiter, instead of the 32 laps originally planned. Last year, engineers detected a problem with check valves in the propulsion system, and NASA decided to forego an engine burn to move Juno into a tighter 14-day orbit around Jupiter. The current 53.4 day orbit will be maintained, but depending on how the spacecraft responds, NASA could extend the mission another three years to give Juno more flybys near Jupiter.

The next science flyby will occur on July 11, when Juno will get some close-up views of the famous Great Red Spot.

Thanks to everyone who works on these images.

Animation of six images acquired by NASA’s Juno spacecraft on March 27, 2017. Credit: NASA/JPL-Caltech/SwRI/MSSS/Jason Major.
This enhanced color view of Jupiter’s south pole was created by citizen scientist Gabriel Fiset using data from the JunoCam instrument on NASA’s Juno spacecraft. Oval storms dot the cloudscape. Approaching the pole, the organized turbulence of Jupiter’s belts and zones transitions into clusters of unorganized filamentary structures, streams of air that resemble giant tangled strings. The image was taken on Dec. 11, 2016 at 9:44 a.m. PST (12:44 p.m. EST), from an altitude of about 32,400 miles (52,200 kilometers) above the planet’s beautiful cloud tops. Credits: NASA/JPL-Caltech/SwRI/MSSS/Gabriel Fiset

Juno is Ready to Tell Us What it Found at Jupiter

The tightly clustered storms that crowd Jupiter's polar regions are another of the gas giant's mysteries. In this image, cyclones the size of Earth bump up against each other at the south pole. Image: NASA/JPL-Caltech/SwRI/MSSS/Betsy Asher Hall/Gervasio Robles
The tightly clustered storms that crowd Jupiter's polar regions are another of the gas giant's mysteries. In this image, cyclones the size of Earth bump up against each other at the south pole. Image: NASA/JPL-Caltech/SwRI/MSSS/Betsy Asher Hall/Gervasio Robles

Even a casual observer can see how complex Jupiter might be. Its Great Red Spot is one of the most iconic objects in our Solar System. The Great Red Spot, which is a continuous storm 2 or 3 times as large as Earth, along with Jupiter’s easily-seen storm cloud belts, are visual clues that Jupiter is a complex place.

We’ve been observing the Great Red Spot for almost 200 years, so we’ve known for a long time that something special is happening at Jupiter. Now that the Juno probe is there, we’re finding that Jupiter might be a more surprising place than we thought.

“There is so much going on here that we didn’t expect that we have had to take a step back and begin to rethink of this as a whole new Jupiter.” – Scott Bolton, Juno’s Principal Investigator at the Southwest Research Institute.

So far, the stunning images delivered to us by the JunoCam have stolen the show. But Juno is a science mission, and the fantastic images we’re feasting on might stir the imagination, but it’s the science that’s at the heart of the mission.

Just one of the many beautiful images of Jupiter we're accustomed to seeing. NASA has invited interested citizens to process JunoCam images and has made them available for anyone to use. NASA / SwRI / MSSS / Gerald Eichstädt / Seán Doran © public domain
Just one of the many beautiful images of Jupiter we’re accustomed to seeing. NASA has invited interested citizens to process JunoCam images and has made them available for anyone to use. NASA / SwRI / MSSS / Gerald Eichstädt / Seán Doran © public domain

The Juno probe arrived at Jupiter in July 2016, and completed its first data-pass on August 27th, 2016. That pass took it to within 4,200 km of Jupiter’s cloud tops. Results from that first pass are being published in the journal Science and in Geophysical Research Letters.

Taken together, the results confirm what we might have guessed by just looking at Jupiter from afar: it is a stormy, complex, turbulent world.

“It was a long trip to get to Jupiter, but these first results already demonstrate it was well worth the journey.” – Diane Brown, Juno Program Executive.

“We are excited to share these early discoveries, which help us better understand what makes Jupiter so fascinating,” said Diane Brown, Juno program executive at NASA Headquarters in Washington. “It was a long trip to get to Jupiter, but these first results already demonstrate it was well worth the journey.”

Jupiter’s Magnetic Field

We’ve known for a long time that Jupiter has the most powerful magnetic field in the Solar System. In fact, the magnetic field is what shaped the design of the Juno probe, and the profile of the mission itself. Juno’s Magnetometer Investigation (MAG) has measured the gas giant’s magnetosphere up close, and these measurements tell us that the magnetic field is even stronger than anticipated, and its shape is more irregular as well. At 7.66 Gauss, the field is about 10 times more powerful than Earth.

The irregularities in the magnetic field are an indication that the field is generated closer to the surface than thought. Earth generates its magnetic field from it its rotating core, but because Jupiter’s is “lumpy”, or stronger in some regions than in others, the gas giant’s magnetic field might be generated above its metallic hydrogen layer.

Results from Juno's first data-pass suggest that Jupiter's powerful magnetic field is generated closer to the surface than previously thought. It may be generated above the core of metallic hydrogen. Image: By Kelvinsong - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=31764016
Results from Juno’s first data-pass suggest that Jupiter’s powerful magnetic field is generated closer to the surface than previously thought. It may be generated above the core of metallic hydrogen. Image: By Kelvinsong – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=31764016

“Juno is giving us a view of the magnetic field close to Jupiter that we’ve never had before,” – Jack Connerney, Juno Deputy Principal Investigator

“Juno is giving us a view of the magnetic field close to Jupiter that we’ve never had before,” said Jack Connerney, Juno deputy principal investigator and the lead for the mission’s magnetic field investigation at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Already we see that the magnetic field looks lumpy: it is stronger in some places and weaker in others. This uneven distribution suggests that the field might be generated by dynamo action closer to the surface, above the layer of metallic hydrogen. Every flyby we execute gets us closer to determining where and how Jupiter’s dynamo works.”

Jupiter’s Atmosphere

Juno’s Microwave Radiometer (MWR) is designed to probe Jupiter’s thick atmosphere. It can detect the thermal microwave radiation in the atmosphere, both at the surface, and much deeper. Data from the MWR shows us that the storm belts are mysteries themselves.

This artist's illustration shows Juno's Microwave Radiometer observing deep into Jupiter's atmosphere. The image shows real data from the 6 MWR channels, arranged by wavelength. Credit: NASA/SwRI/JPL
This artist’s illustration shows Juno’s Microwave Radiometer observing deep into Jupiter’s atmosphere. The image shows real data from the 6 MWR channels, arranged by wavelength. Credit: NASA/SwRI/JPL

The belts near Jupiter’s equator extend deep into the atmosphere, while other belts seem to evolve and transform into other structures. The MWR can probe a few hundred kilometers into the atmosphere, where it has found variable and increasing amounts of ammonia to that depth.

Polar Regions and Auroras

Jupiter is home to intense aurora activity at both poles. One of Juno’s mission goals is to study those auroras and the powerful polar magnetic fields that create them. Initial observations from Juno suggest that they are formed differently than Earthly auroras.

Juno is in a unique position to study the magnetosphere and the auroras. Its elongated polar orbit allows it to span the entire magnetosphere all the way from the bow shock to the planet itself.

The tilt of Juno's orbit relative to Jupiter changes over the course of the mission, sending the spacecraft increasingly deeper into the planet's intense radiation belts. This also gives Juno the ability to study the structure of the magnetosphere. Credit: NASA/JPL-Caltech
The tilt of Juno’s orbit relative to Jupiter changes over the course of the mission, sending the spacecraft increasingly deeper into the planet’s intense radiation belts. This also gives Juno the ability to study the structure of the magnetosphere. Credit: NASA/JPL-Caltech

According to the paper detailing the initial data on Jupiter’s magnetosphere an auroras, many of the observations have “terrestrial analogs.” But other aspects are very Jovian, and have no counterpart on Earth.

“…a radically different conceptual model of Jupiter’s interaction with its space environment.” – from J. E. P. Connerney et. al., 2017

As the authors say in their summary, “We observed plasmas upwelling from the ionosphere, providing a mechanism whereby Jupiter helps populate its magnetosphere. The weakness of the magnetic field-aligned electric currents associated with the main aurora and the broadly distributed nature of electron beaming in the polar caps suggest a radically different conceptual model of Jupiter’s interaction with its space environment.”

Polar Storms

JunoCam has also found some puzzling features in Jupiter’s atmosphere. The poles themselves are populated by densely clustered, swirling storms the size of Earth. Since they’ve only been observed briefly, there are a host of unanswered questions about them.

“We’re puzzled as to how they could be formed, how stable the configuration is, and why Jupiter’s north pole doesn’t look like the south pole.” – Scott Bolton, Juno’s Principal Investigator at the Southwest Research Institute

“We’re puzzled as to how they could be formed, how stable the configuration is, and why Jupiter’s north pole doesn’t look like the south pole,” said Bolton. “We’re questioning whether this is a dynamic system, and are we seeing just one stage, and over the next year, we’re going to watch it disappear, or is this a stable configuration and these storms are circulating around one another?”

The tightly clustered storms that crowd Jupiter's polar regions are another of the gas giant's mysteries. In this image, cyclones the size of Earth bump up against each other at the south pole. Image:  NASA/JPL-Caltech/SwRI/MSSS/Betsy Asher Hall/Gervasio Robles
The tightly clustered storms that crowd Jupiter’s polar regions are another of the gas giant’s mysteries. In this image, cyclones the size of Earth bump up against each other at the south pole. Image: NASA/JPL-Caltech/SwRI/MSSS/Betsy Asher Hall/Gervasio Robles

The Great Red Spot: Juno’s Next Target

Juno’s purposeful orbit takes it extremely close to the cloud tops, where it can perform powerful science. But the orbit also takes it a long way from Jupiter. Every 53 days it takes another plunge at Jupiter, where it gathers its next set of observations.

“Every 53 days, we go screaming by Jupiter, get doused by a fire hose of Jovian science, and there is always something new.” – Scott Bolton, Juno’s Principal Investigator at the Southwest Research Institute.

“Every 53 days, we go screaming by Jupiter, get doused by a fire hose of Jovian science, and there is always something new,” said Bolton. “On our next flyby on July 11, we will fly directly over one of the most iconic features in the entire solar system — one that every school kid knows — Jupiter’s Great Red Spot. If anybody is going to get to the bottom of what is going on below those mammoth swirling crimson cloud tops, it’s Juno and her cloud-piercing science instruments.”

The JunoCam's next target: Jupiter's iconic Great Red Spot. Image:  NASA/JPL-Caltech/SwRI/MSSS/Roman Tkachenko
Juno’s next target: Jupiter’s iconic Great Red Spot. Image: NASA/JPL-Caltech/SwRI/MSSS/Roman Tkachenko

During each pass, Juno collects about 6 megabytes of data, which it sends back to Earth via the Deep Space Network. After that, the data is analyzed and published.

Juno has many more fly-bys of Jupiter before it’s sent to its end in the atmosphere of Jupiter. We can expect many more surprises, and hopefully some answers, between now and then.

Juno’s Monday Jupiter Flyby Promises New Batch of Images & Science

This image of Jupiter from the Juno probe shows an intricate dance of storms and swirls. The enhanced color image was captured on February 2nd, from only 14,500 km above the gas giant's cloud tops. Image: NASA/JPL-Caltech/SwRI/MSSS/Roman Tkachenko

Juno is only part way through its mission to Jupiter, and already we’ve seen some absolutely breathtaking images of the gas giant. On Monday, the Juno spacecraft will flyby Jupiter again. This will be the craft’s 5th flyby of the gas giant, and it’ll provide us with our latest dose of Jupiter science and images. The first 4 flybys have already exceeded our expectations.

Juno will approach to within 4,400 km of Jupiter’s cloud tops, and will travel at a speed of 207,600 km/h. During this time of closest approach, called a perijove, all of Juno’s eight science instruments will be active, along with the JunoCam.

The JunoCam is not exactly part of the science payload. It was included in the missions to help engage the public with the mission, and it appears to be doing that job well. The Junocam’s targets have been partly chosen by the public, and NASA has invited anyone who cares to to download and process raw Junocam images. You can see those results throughout this article.

This image of Jupiter’s dancing cloud tops was captured during perijove 3. Image: NASA / JPL-Caltech / SwRI / MSSS / Kootenay Nature Photos © cc nc sa

This is Juno’s 5th flyby, but only its 4th science pass. During Juno’s first encounter with Jupiter, the science instruments weren’t active. Even so, after only 3 science passes, we have learned some things about Jupiter.

“We are excited to see what new discoveries Juno will reveal.” – Scott Bolton, NASA’s Principal Investigator for the Juno Mission

“This will be our fourth science pass — the fifth close flyby of Jupiter of the mission — and we are excited to see what new discoveries Juno will reveal,” said Scott Bolton, principal investigator of Juno from the Southwest Research Institute in San Antonio. “Every time we get near Jupiter’s cloud tops, we learn new insights that help us understand this amazing giant planet.”

We’ve already learned that Jupiter’s intense magnetic fields are much more complicated than we thought. We’ve learned that the belts and zones in Jupiter’s atmosphere, which are responsible for the dazzling patterns on the cloud tops, extend much deeper into the atmosphere than we thought. And we’ve discovered that charged material expelled from Io’s volcanoes helps cause Jupiter’s auroras.

The South Pole of Jupiter, taken during perijove 3. Image: NASA / JPL-Caltech / SwRI / MSSS / Luca Fornaciari © cc nc sa

Juno has the unprecedented ability to get extremely close to Jupiter. This next flyby will bring it to within 4,400 km of the cloud tops. But to do so, Juno has to pay a price. Though the sensitive equipment on the spacecraft is protected inside a titanium vault, Jupiter’s powerful radiation belts will still take a toll on the electronics. But that’s the price Juno will pay to perform its mission.

Jupiter’s dazzle as revealed by JunoCam and Shane Drever. Image: NASA / JPL-Caltech / SwRI / MSSS / Shane Drever © cc nc sa

Other missions, like Cassini, have been measured in years, while Juno’s will be measured in orbits. And once it’s completed its final orbit, it will be sent to its destruction in Jupiter’s atmosphere.

But before that happens, there’s a lot of science to be done, and a lot of stunning images to be captured.

Here’s an interview with the man leading the Juno Mission: Understanding Juno’s Orbit: An Interview with NASA’s Scott Bolton.

Here is the page for the JunoCam: https://www.missionjuno.swri.edu/junocam

Juno Will Get No Closer To Jupiter Due To Engine Troubles

Jupiter’s south pole. captured by the JunoCam on Feb. 2, 2017, from an altitude of about 62,800 miles (101,000 kilometers) above the cloud tops. Credits: NASA/JPL-Caltech/SwRI/MSSS/John Landino

On July 4th, 2016, the Juno mission established orbit around Jupiter, becoming the second spacecraft in history to do so (after the Galileo probe). Since then, the probe has been in a regular 53.4-day orbit (known as perijove), moving between the poles to avoid the worst of its radiation belts. Originally, Juno’s mission scientists had been hoping to reduce its orbit to a 14-day cycle so the probe could make more passes to gather more data.

To do this, Juno was scheduled for an engine burn on Oct. 19th, 2016, during its second perijovian maneuver. Unfortunately, a technical error prevented this  from happening. Ever since, the mission team has been pouring over mission data to determine what went wrong and if they could conduct an engine burn at a later date. However, the mission team has now concluded that this won’t be possible.

The technical glitch which prevented the firing took place weeks before the engine burn was scheduled to take place, and was traced to two of the engines helium check valves. After the propulsion system was pressurized, the valves took several minutes to open – whereas they took only seconds during previous engine burns. Because of this, the mission leaders chose to postpone the firing until they could get a better understanding of why the glitch happened.

This amateur-processed image was taken on Dec. 11th, 2016, at 9:27 a.m. PST (12:27 p.m. EST), as NASA’s Juno spacecraft performed its third close flyby of Jupiter. Credits: NASA/JPL-Caltech/SwRI/MSSS/Eric Jorgensen

And after pouring over mission data from the past few months and performing calculations on possible maneuvers, Juno’s science team came to the conclusion that an engine burn might be counter-productive at this point. As Rick Nybakken, the Juno project manager at NASA’s Jet Propulsion Laboratory (JPL), explained in a recent NASA press release:

“During a thorough review, we looked at multiple scenarios that would place Juno in a shorter-period orbit, but there was concern that another main engine burn could result in a less-than-desirable orbit. The bottom line is a burn represented a risk to completion of Juno’s science objectives.”

However, this is not exactly bad news for the mission. It’s current perijove orbit takes it from one pole to the other, allowing it to pass over the cloud tops at a distance of around 4,100 km (2,600 mi) at its closest. At its farthest, the spacecraft reaches a distance of 8.1 million km (5.0 million mi) from the gas giant, which places it far beyond the orbit of Callisto.

During each pass, the probe is able to peak beneath the thick clouds to learn more about the planet’s atmosphere, internal structure, magnetosphere, and formation. And while a 14-day orbital period would allow for it to conduct 37 orbits before its mission is scheduled to wrap up, its current 53.4-day period will allow for more information to be collected on each pass.

And as Thomas Zurbuchen, the associate administrator for NASA’s Science Mission Directorate in Washington, declared:

“Juno is healthy, its science instruments are fully operational, and the data and images we’ve received are nothing short of amazing. The decision to forego the burn is the right thing to do – preserving a valuable asset so that Juno can continue its exciting journey of discovery.”

In the meantime, the Juno science team is still analyzing the returns from Juno’s four previous flybys – which took place on August 27th, October 19th, December 11th, and February 2nd, 2017, respectively. With each pass, more information is revealed about the planet’s magnetic fields, aurorae, and banded appearance. The next perijovian maneuver will take place on March 27th, 2017, and will result in more images and data being collected.

Before the mission concludes, the Juno spacecraft will also explore Jupiter’s far magnetotail, its southern magnetosphere, and its magnetopause. The mission is also conducting an outreach program with its JunoCam, which is being guided with assistance of the public. Not only can people vote on which features they want imaged with every flyby, but these images are accessible to “citizen scientists” and amateur astronomers.

Under its current budget plan, Juno will continue to operate through to July 2018, conducting a total of 12 science orbits. At this point, barring a mission extension, the probe will be de-orbited and burn up in Jupiter’s outer atmosphere. As with the Galileo spacecraft, this will be as to avoid any possibility of impact and biological contamination with one of Jupiter’s moons.

Further Reading: NASA

Juno Buzzes Jupiter a mere 4,300 Km’s above the Cloud Tops

Illustration of NASA's Juno spacecraft firing its main engine to slow down and go into orbit around Jupiter. Lockheed Martin built the Juno spacecraft for NASA's Jet Propulsion Laboratory. Credit: NASA/Lockheed Martin

On July 4th, 2016, NASA’s Juno spacecraft made history when it became the second mission to establish orbit around Jupiter – the previous being the Galileo spacecraft, which orbited the planet from 1995 to 2003. Since that time, it has circled the massive gas giant three times, collecting data on the gas giant’s composition, interior and gravity field.

This past Thursday, February 1st, the mission conducted its fourth orbit of the planet. In the process, the spacecraft collected more vital data on the gas giant and snapped several dozen pictures. And in what is has been a first for a space mission, NASA will once again be asking the public what features they would like to see photographed during Juno’s next pass.

Juno made its closest pass (what is known as perijove) to Jupiter at precisely 1257 GMT (7:57 a.m. EST), passing the cloud tops at a distance of 4,300 km (2,670 mi) and traveling at a velocity of about 208,000 km/h (129,300 mph) relative to the gas giant. Using its suite of instruments, it scanned Jupiter’s atmosphere, gathered data on its radiation and plasma, and began returning this information to Earth.

Processed image taken on Dec. 11, 2016, at 9:27 a.m. PST (12:27 p.m. EST) by the NASA Juno spacecraft, as it performed its third close flyby of Jupiter. Credits: NASA/JPL-Caltech/SwRI/MSSS/Eric Jorgensen

And during this latest pass, the JunoCam snapped several dozen more pictures. During two of its three previous perijove maneuvers, this instruments captured some of the most breathtaking photographs of Jupiter’s clouds to date (like the one seen above). Once they were transmitted back to Earth and made available to the public, “citizen scientistswere able to download and process them at their leisure.

And with this latest pass complete, the public is once again being encouraged to vote on what features they want to see photographed during the next pass. As Candy Hansen, the Juno mission’s co-investigator from the Planetary Science Institute, stated shortly before Juno made its fourth perijovian maneuver:

“The pictures JunoCam can take depict a narrow swath of territory the spacecraft flies over, so the points of interest imaged can provide a great amount of detail. They play a vital role in helping the Juno science team establish what is going on in Jupiter’s atmosphere at any moment. We are looking forward to seeing what people from outside the science team think is important.”

This has all been part of a first-ever effort on behalf of NASA to get the public involved in what kinds of images are to be taken. According to NASA, this is to become a regular feature of the Juno mission, with a  new voting page being created for each upcoming flyby. The next perijovian maneuver will take place on March 27th, 2017, coinciding with the Juno spacecraft’s 53.4-day orbital period.

False color view of Jupiter’s polar haze, created by citizen scientist Gerald Eichstädt using data from the JunoCam instrument. Credit: NASA/JPL-Caltech/SwRI/MSSS/Eric Jorgensen

Originally, the mission planners had hoped to narrow Juno’s orbital period down to 14 days, which would have been accomplished by having the craft fire its main engine while at perijove. However, two weeks before the engine burn was scheduled to take place (Oct. 19th, 2016), ground controllers noticed a problem with two of the engine’s check valves – which are part of the spacecraft’s fuel pressurization system.

As Juno project manager Rick Nybakken said at the time:

“Telemetry indicates that two helium check valves that play an important role in the firing of the spacecraft’s main engine did not operate as expected during a command sequence that was initiated yesterday. The valves should have opened in a few seconds, but it took several minutes. We need to better understand this issue before moving forward with a burn of the main engine.”

Because of this technical issue, the mission leaders chose to postpone the engine burn so they could check the craft’s instruments to get a better understanding of why it happened. The Juno team was hoping to use the third orbit of the spacecraft to study the problem, but this was interrupted when a software performance monitor induced a reboot of the spacecraft’s onboard computer.

To accomplish its science objectives, Juno is orbiting Jupiter’s poles and passing very close to the planet, avoiding the most powerful (and hazardous) radiation belts in the process. Credit: NASA/JPL-Caltech

Because of this, the spacecraft went into safe mode during its third flyby, which prevented them from gathering data on the engine valve problem. On Oct. 24th, the mission controllers managed to get the craft to exit safe mode and performed a trim maneuver in preparation for its next flyby. But the mystery of why the engine valves failed to open remains, and the mission team is still unable to resolve the problem.

Thus, the decision to fire the main engine (thereby shortening its orbital period) has been postponed until they get it back online. But as Scott Bolton – the Associate Director of R&D at the Southwest Research Institute (SwRI) and Juno’s Principal Investigator – has emphasized in the past:

“It is important to note that the orbital period does not affect the quality of the science that takes place during one of Juno’s close flybys of Jupiter. The mission is very flexible that way. The data we collected during our first flyby on August 27th was a revelation, and I fully anticipate a similar result from Juno’s October 19th flyby.”

In the meantime, the Juno science team is still analyzing data from all previous Jupiter flybys. During each pass, the spacecraft and its instruments peer beneath Jupiter’s dense cloud cover to study its auroras, its magnetic field, and to learn more about the planet’s structure, composition, and formation. And with the public’s help, it is also providing some of the clearest and most detailed imagery of the gas giant to date.

Further Reading: NASA

 

A Proposal For Juno To Observe The Volcanoes Of Io

Io and volcanic plume. Credit: NASA/JPL-Caltech
To accomplish its science objectives, NASA’s Juno spacecraft orbits over Jupiter’s poles and passes repeatedly through hazardous radiation belts. Two Boston University researchers propose using Juno to probe the ever-changing flux of volcanic gases-turned-ions spewed by Io’s volcanoes. Credit: NASA/JPL-Caltech

Jupiter may be the largest planet in the Solar System with a diameter 11 times that of Earth, but it pales in comparison to its own magnetosphere. The planet’s magnetic domain extends sunward at least 3 million miles (5 million km) and on the back side all the way to Saturn for a total of 407 million miles or more than 400 times the size of the Sun.

Jupiter’s large magnetic field interacts with the solar wind to form an invisible magnetosphere. If we were able to see it, it would span at least several degrees of sky. It would show its greatest extent when viewing Jupiter from the side at quadrature, when the planet stands due south at sunrise or sunset.In the artist’s depiction, the planet would be located between the two “purple eyes” — too small to see at this scale. Credit: NASA.

If we had eyes adapted to see the Jovian magnetosphere at night, its teardrop-like shape would easily extend across several degrees of sky! No surprise then that Jove’s magnetic aura has been called one of the largest structures in the Solar System.

A 5-frame sequence taken by the New Horizons spacecraft in May 2007 shows a cloud of volcanic debris from Io’s Tvashtar volcano. The plume extends some 200 miles (330 km) above the moon’s surface. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Io, Jupiter’s innermost of the planet’s four large moons, orbits deep within this giant bubble. Despite its small size — about 200 miles smaller than our own Moon — it doesn’t lack in superlatives. With an estimated 400 volcanoes, many of them still active, Io is the most volcanically active body in the Solar System. In the moon’s low gravity, volcanoes spew sulfur, sulfur dioxide gas and fragments of basaltic rock up to 310 miles (500 km) into space in beautiful, umbrella-shaped plumes.

This schematic of Jupiter’s magnetic environments shows the planets looping magnetic field lines (similar to those generated by a simple bar magnet), Io and its plasma torus and flux tube. Credit: John Spencer / Wikipedia CC-BY-SA3.0 with labels by the author

Once aloft, electrons whipped around by Jupiter’s powerful magnetic field strike the neutral gases and ionize them (strips off their electrons). Ionized atoms and molecules (ions) are no longer neutral but possess a positive or negative electric charge. Astronomers refer to swarms of ionized atoms as plasma.

Jupiter rotates rapidly, spinning once every 9.8 hours, dragging the whole magnetosphere with it. As it spins past Io, those volcanic ions get caught up and dragged along for the ride, rotating around the planet in a ring called the Io plasma torus. You can picture it as a giant donut with Jupiter in the “hole” and the tasty, ~8,000-mile-thick ring centered on Io’s orbit.

That’s not all. Jupiter’s magnetic field also couples Io’s atmosphere to the planet’s polar regions, pumping Ionian ions through two “pipelines” to the magnetic poles and generating a powerful electric current known as the Io flux tube. Like firefighters on fire poles, the ions follow the planet’s magnetic field lines into the upper atmosphere, where they strike and excite atoms, spawning an ultraviolet-bright patch of aurora within the planet’s overall aurora. Astronomers call it Io’s magnetic footprint. The process works in reverse, too, spawning auroras in Io’s tenuous atmosphere.

The tilt of Juno’s orbit relative to Jupiter changes over the course of the mission, sending the spacecraft increasingly deeper into the planet’s intense radiation belts. Orbits are numbered from early in the mission to late. Credit: NASA/JPL-Caltech

Io is the main supplier of particles to Jupiter’s magnetosphere. Some of the same electrons stripped from sulfur and oxygen atoms during an earlier eruption return to strike atoms shot out by later blasts. Round and round they go in a great cycle of microscopic bombardment! The constant flow of high-speed, charged particles in Io’s vicinity make the region a lethal environment not only for humans but also for spacecraft electronics, the reason NASA’s Juno probe gets the heck outta there after each perijove or closest approach to Jupiter.

Io’s flux tube directs ions down Jupiter’s magnetic field lines to create magnetic footprints of enhanced aurora in Jupiter’s polar regions. An electric current of 5 million amps flows along Io’s flux tube.Credit: NASA/J.Clarke/HST

But there’s much to glean from those plasma streams.  Astronomy PhD student Phillip Phipps and assistant professor of astronomy Paul Withers of Boston University have hatched a plan to use the Juno spacecraft to probe Io’s plasma torus to indirectly study the timing and flow of material from Io’s volcanoes into Jupiter’s magnetosphere. In a paper published on Jan. 25, they propose using changes in the radio signal sent by Juno as it passes through different regions of the torus to measure how much stuff is there and how its density changes over time.

The technique is called a radio occultation. Radio waves are a form of light just like white light. And like white light, they get bent or refracted when passing through a medium like air (or plasma in the case of Io). Blue light is slowed more and experiences the most bending; red light is slowed less and refracted least, the reason red fringes a rainbow’s outer edge and blue its inner. In radio occultations, refraction results in changes in frequency caused by variations in the density of plasma in Io’s torus.

The best spacecraft for the attempt is one with a polar orbit around Jupiter, where it cuts a clean cross-section through different parts of the torus during each orbit. Guess what? With its polar orbit, Juno’s the probe for the job! Its main mission is to map Jupiter’s gravitational and magnetic fields, so an occultation experiment jives well with mission goals. Previous missions have netted just two radio occultations of the torus, but Juno could potentially slam dunk 24.

New Horizons took this photo of Io in infrared light. The Tvastar volcano is bright spot at top. At least 10 other volcanic hot spots dot the moon’s night side. Credit: NASA/JHUPL/SRI

Because the paper was intended to show that the method is a feasible one, it remains to be seen whether NASA will consider adding a little extra credit work to Juno’s homework. It seems a worthy and practical goal, one that will further enlighten our understanding of how volcanoes create aurorae in the bizarre electric and magnetic environment of the largest planet.

Juno Just Took One Of The Best Images Of Jupiter Ever

A portion of a new image taken by the JunoCam imager on NASA’s Juno spacecraft of Jupiter’s northern latitudes on Dec. 11, 2016. Credit: NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstaedt/John Rogers.

Wow! If you’ve ever wanted to know what it would be like to hang above Jupiter’s clouds, here you go. This absolutely stunning view of Jupiter’s northern latitudes shows incredible detail of gas giant’s swirling cloudtops. And it features, in the lower left in the image below, the storm on the gas planet known as NN-LRS-1, or more colloquially, the Little Red Spot.

The JunoCam imager on NASA’s Juno spacecraft snapped this shot of Jupiter’s northern latitudes on Dec. 11, 2016. Credit: NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstaedt/John Rogers.

Juno’s JunoCam, a visible light camera, is able to get never-before-seen images like this because it is doing something that no other mission to Jupiter has done.

“The spacecraft’s proximity to Jupiter is very unusual,” Rick Nybakken told me during an interview at JPL last year. Nybakken is Juno’s project manager. “Juno has an elliptical orbit that brings it just 3,107 miles (5,000 km) above the cloud tops. No other mission has been this close, and we’re right on top of Jupiter so to speak.”

Special instruments are studying Jupiter’s radiation belt and magnetosphere, its interior structure, and the turbulent atmosphere, as well as providing views of the planet with spectacular, close-up images.

And another great thing about this image is that it was processed by citizen scientists. Gerald Eichstaedt and John Rogers processed the image and drafted the caption, and this will be the norm for many of the JunoCam images, because it’s “the public’s camera.”

“I’m excited though for what we’re doing with the visible light camera,” said Juno Project Scientist Steve Levin, who I also interviewed at JPL. “We’re making JunoCam as much as much as we possibly can an instrument that belongs to the public. We’ll solicit the aid of the public in picking which images to take, and releasing the data in its rawest form, and allow people to go and make the images.”

Scientist Candy Hansen is leading this citizen science effort, and she uses the phrase, “science in a fishbowl,” meaning the JunoCam team is showing people what it is like to do science by allowing anyone to participate and see the data as it arrives from Juno.

Damian Peach reprocessed one of the latest images taken by Juno’s JunoCam during its 3rd close flyby of the planet on Dec. 11. The photo highlights two large ‘pearls’ or storms in Jupiter’s atmosphere. Credit: NASA/JPL-Caltech/SwRI/MSSS

You can find the raw images here, so go ahead and test out your image processing skills.

JunoCam is designed to capture remarkable pictures of Jupiter’s poles and cloud tops. Although its images will be helpful to the science team to help provide context for the spacecraft’s other instruments, it is not considered one of the mission’s science instruments. JunoCam was included on the spacecraft specifically for purposes of engaging and including the public.

The Little Red Spot is the third largest anticyclonic oval on the planet, which Earth-based observers have tracked for the last 23 years. An anticyclone is a weather phenomenon with large-scale circulation of winds around a central region of high atmospheric pressure. They rotate clockwise in the northern hemisphere, and counterclockwise in the southern hemisphere. The Little Red Spot shows very little color these days, just a pale brown smudge in the center. Back in 2006, the storm was stronger and the color changed darker and more red. Now, with the storm not quite as active, the color is very similar to the surroundings, making it difficult to see.

If you’d like to download a larger version of this processed image (need a new wallpaper?) you can find it on NASA’s website.

Juno Captures a Stunning Jovian ‘Pearl’

New Juno image of Jupiter taken on Dec. 11, 2016. Processed by Damian Peach
Damian Peach reprocessed one of the latest images taken by Juno's JunoCam during its 3rd close flyby of the planet on Dec. 11. The photo highlights two large 'pearls' or storms in Jupiter's atmosphere. Credit: NASA/JPL-Caltech/SwRI/MSSS
Astro-imager Damian Peach reprocessed one of the latest images taken by Juno’s JunoCam during its 3rd close flyby of the planet on Dec. 11. The photo highlights one of the large ‘pearls’ (right) that forms a string of  storms in Jupiter’s atmosphere. A smaller isolated storm is seen at left. Credit: NASA/JPL-Caltech/SwRI/MSSS

Jupiter looks beautiful in pearls! This image, taken by the JunoCam imager on NASA’s Juno spacecraft, highlights one of the eight massive storms that from a distance form a ‘string of pearls’ on Jupiter’s turbulent atmosphere. They’re counterclockwise rotating storms that appear as white ovals in the gas giant’s southern hemisphere. The larger pearl in the photo above is roughly half the size of Earth. Since 1986, these white ovals have varied in number from six to nine with eight currently visible.

Four more 'pearls' in the string of eight photographed on Dec. 10, 2016. They show up well in photos but require good seeing and at least and 8-inch telescope to see. Credit: Christopher Go
Four more ‘pearls’ photographed on Dec. 10, 2016 in the planet’s South Temperate Belt below the Great Red Spot. The moon Ganymede is at left. The show up well in photos but require good seeing and at least and 8-inch telescope to see visually. Credit: Christopher Go

The photos were taken during Sunday’s close flyby. At the time of closest approach — called perijove — Juno streaked about 2,580 miles (4,150 km) above the gas giant’s roiling, psychedelic cloud tops traveling about 129,000 mph or nearly 60 km per second relative to the planet. Seven of Juno’s eight science instruments collected data during the flyby. At the time the photos were taken, the spacecraft was about 15,300 miles (24,600 km) from the planet.

This is the original image sent by JunoCam on Dec. 11 and shows the 8th of the eight oval or 'pearls'in Jupiter's roiling atmosphere. Credit: NASA/JPL-Caltech/SwRI/MSSS
This is the original image sent by JunoCam on Dec. 11 and features the eighth in a string of large storms in the planet’s southern hemisphere. Credit: NASA/JPL-Caltech/SwRI/MSSS

JunoCam is a color, visible-light camera designed to capture remarkable pictures of Jupiter’s poles and cloud tops. As Juno’s eyes, it will provide a wide view, helping to provide context for the spacecraft’s other instruments. JunoCam was included on the spacecraft specifically for purposes of public engagement; although its images will be helpful to the science team, it is not considered one of the mission’s science instruments.

4-frame animation spans 24 Jovian days, or about 10 Earth days. The passage of time is accelerated by a factor of 600,000. Credit: NASA
4-frame animation spans 24 Jovian days, or about 10 Earth days. The passage of time is accelerated by a factor of 600,000. Some of the ovals are visible as well as a variety of jets – west to east and east to west. Credit: NASA

The crazy swirls of clouds we see in the photos are composed of ammonia ice crystals organized into a dozen or so bands parallel to the equator called belts (the darker ones) and zones. The border of each is bounded by a powerful wind flow called a jet, resembling Earth’s jet streams, which alternate direction from one band to the next.

Zones are colder and mark latitudes where material is upwelling from below. Ammonia ice is thought to give the zones their lighter color. Belts in contrast indicate sinking material; their color is a bit mysterious and may be due to the presence of hydrocarbons — molecules that are made from hydrogen, carbon, and oxygen as well as exotic sulfur and phosphorus compounds.

Use this guide to help you better understand Jupiter's arrangement of belts and zones, many of which are visible in amateur telescopes. Credit: NASA/JPL/Wikipedia
Use this guide to help you better understand Jupiter’s arrangement of belts and zones, many of which are visible in amateur telescopes. Credit: NASA/JPL/Wikipedia

The pearls or storms form in windy Jovian atmosphere and can last many decades. Some eventually dissipate while others merge to form even larger storms. Unlike hurricanes, which fall apart when they blow inland from the ocean, there’s no “land” on Jupiter, so storms that get started there just keep on going. The biggest, the Great Red Spot, has been hanging around causing trouble and delight (for telescopic observers) for at least 350 years.

Juno’s next perijove pass will happen on Feb. 2, 2017.

Juno Captures Jupiter’s Enthralling Poles From 2,500 Miles

JunoCam captured this image of Jupiter's north pole region from a distance of 78,000 km (48,000 miles) above the planet.
JunoCam captured this image of Jupiter's north pole region from a distance of 78,000 km (48,000 miles) above the planet.

Juno is sending data from Jupiter back to us, courtesy of the Deep Space Network, and the first images are meeting our hyped-up expectations. On August 27, the Juno spacecraft came within about 4,200 km. (2,500 miles) of Jupiter’s cloud tops. All of Juno’s instruments were active, and along with some high-quality images in visual and infrared, Juno also captured the sound that Jupiter produces.

Juno has captured the first images of Jupiter’s north pole. Beyond their interest as pure, unprecedented eye candy, the images of the pole reveal things never before seen. They show storm activity and weather patterns that are seen nowhere else in our solar system. Even on the other gas giants.

“…like nothing we have seen or imagined before.”

“First glimpse of Jupiter’s north pole, and it looks like nothing we have seen or imagined before,” said Scott Bolton, principal investigator of Juno from the Southwest Research Institute in San Antonio. “It’s bluer in color up there than other parts of the planet, and there are a lot of storms. There is no sign of the latitudinal bands or zone and belts that we are used to — this image is hardly recognizable as Jupiter. We’re seeing signs that the clouds have shadows, possibly indicating that the clouds are at a higher altitude than other features.”

The iconic storm bands of Jupiter are absent in this JunoCam image of Jupiter's northern polar region. Instead, the region is dominated by swirling storm patterns reminiscent of hurricanes here on Earth. Image: NASA/JPL-Caltech/SwRI/MSSS
The iconic storm bands of Jupiter are absent in this JunoCam image of Jupiter’s northern polar region. Instead, the region is dominated by swirling storm patterns reminiscent of hurricanes here on Earth. Image: NASA/JPL-Caltech/SwRI/MSSS

The visible light images of Jupiter’s north pole are very different from our usual perception of Jupiter. People have been looking at Jupiter for a long time, and the gas giant’s storm bands, and the Great Red Spot, are iconic. But the north polar region looks completely different, with whirling, rotating storms similar to hurricanes here on Earth.

The Junocam instrument is responsible for the visible light pictures of Jupiter that we all enjoy. But the Jovian Infrared Auroral Mapper (JIRAM) is showing us a side of Jupiter that the naked eye will never see.

The Juno Infrared Auroral Mapper (JIRAM) captured this infrared image of Jupiter's south pole. This part of Jupiter cannot be seen from Earth. Image: NASA/JPL-Caltech/SwRI/MSSS
The Juno Infrared Auroral Mapper (JIRAM) captured this infrared image of Jupiter’s south pole. This part of Jupiter cannot be seen from Earth. Image: NASA/JPL-Caltech/SwRI/MSSS

“JIRAM is getting under Jupiter’s skin, giving us our first infrared close-ups of the planet,” said Alberto Adriani, JIRAM co-investigator from Istituto di Astrofisica e Planetologia Spaziali, Rome. “These first infrared views of Jupiter’s north and south poles are revealing warm and hot spots that have never been seen before. And while we knew that the first-ever infrared views of Jupiter’s south pole could reveal the planet’s southern aurora, we were amazed to see it for the first time.”

“No other instruments, both from Earth or space, have been able to see the southern aurora.”

Even when we’re prepared to be amazed by what Juno and other spacecraft show us, we are still amazed. It’s impossible to see Jupiter’s south pole from Earth, so these are everybody’s first glimpses of it.

“No other instruments, both from Earth or space, have been able to see the southern aurora,” said Adriani. “Now, with JIRAM, we see that it appears to be very bright and well-structured. The high level of detail in the images will tell us more about the aurora’s morphology and dynamics.”

Beyond the juicy images of Jupiter are some sound recordings. It’s been known since about the 1950’s that Jupiter is a noisy planet. Now Juno’s Radio/Plasma Wave Experiment (WAVE) has captured a recording of that sound.

“Jupiter is talking to us in a way only gas-giant worlds can,” said Bill Kurth, co-investigator for the Waves instrument from the University of Iowa, Iowa City. “Waves detected the signature emissions of the energetic particles that generate the massive auroras which encircle Jupiter’s north pole. These emissions are the strongest in the solar system. Now we are going to try to figure out where the electrons come from that are generating them.”

Oddly enough, that’s pretty much exactly what I expected Jupiter to sound like. Like something from an early sci-fi film.

There’s much more to come from Juno. These images and recordings of Jupiter are just the result of Juno’s first orbit. There are over 30 more orbits to come, as Juno examines the gas giant as it orbits beneath it.

JUNO Transmits First Up-Close Look Soarin’ over Jupiter

Jupiter's north polar region is coming into view as NASA's Juno spacecraft approaches the giant planet. This view of Jupiter was taken on August 27, when Juno was 437,000 miles (703,000 kilometers) away. Credits: NASA/JPL-Caltech/SwRI/MSSS
Jupiter's north polar region is coming into view as NASA's Juno spacecraft approaches the giant planet. This view of Jupiter was taken on August 27, when Juno was 437,000 miles (703,000 kilometers) away.   Credits: NASA/JPL-Caltech/SwRI/MSSS
Jupiter’s north polar region is coming into view as NASA’s Juno spacecraft approaches the giant planet. This view of Jupiter was taken on August 27, when Juno was 437,000 miles (703,000 kilometers) away. Credits: NASA/JPL-Caltech/SwRI/MSSS

NASA’s JUNO spacecraft successfully swooped over the Jovian cloud tops today, Saturday, Aug. 27, gathering its first up close images and science observations of the ‘King of the Planets’ since braking into orbit on America’s Independence Day.

Saturdays’ close encounter with Jupiter soaring over its north pole was the first of 36 planned orbital flyby’s by Juno during the scheduled 20 month long prime mission.

“Soarin’ over #Jupiter. My 1st up-close look of the gas-giant world was a success!” the probe tweeted today post-flyby.

NASA released Juno’s first up-close image taken by the JunoCam visible light camera just hours later – as seen above.

Juno was speeding at some 130,000 mph (208,000 kilometers per hour) during the time of Saturday’s closest approach at 9:44 a.m. EDT (6:44 a.m. PDT 13:44 UTC) over the north polar region.

It passed merely 2,600 miles (4,200 kilometers) above the turbulent clouds of the biggest planet in our solar system during its initial 53.5 day polar elliptical capture orbit.

And apparently everything proceeded as the science and engineering team leading the mission to the gas giant had planned.

“Early post-flyby telemetry indicates that everything worked as planned and Juno is firing on all cylinders,” said Rick Nybakken, Juno project manager at NASA’s Jet Propulsion Laboratory in Pasadena, California, in a statement.

This dual view of Jupiter was taken on August 23, when NASA's Juno spacecraft was 2.8 million miles (4.4 million kilometers) from the gas giant planet on the inbound leg of its initial 53.5-day capture orbit. Credit: NASA/JPL-Caltech/SwRI/MSSS
This dual view of Jupiter was taken on August 23, when NASA’s Juno spacecraft was 2.8 million miles (4.4 million kilometers) from the gas giant planet on the inbound leg of its initial 53.5-day capture orbit. Credit: NASA/JPL-Caltech/SwRI/MSSS

Indeed Saturday’s encounter will count as the closest of the entire prime mission. It also marks the first time that the entire suite of nine state-of-the-art science instruments had been turned on to gather the totally unique observations of Jupiter’s interior and exterior environment.

“We are getting some intriguing early data returns as we speak,” said Scott Bolton, principal investigator of Juno from the Southwest Research Institute in San Antonio, in a statement.

“This is our first opportunity to really take a close-up look at the king of our solar system and begin to figure out how he works.”

Additional up-close high resolution imagery of the Jovian atmosphere, swirling cloud tops and north and south poles snapped by JunoCam will be released in the coming weeks, perhaps as soon as next week.

“We are in an orbit nobody has ever been in before, and these images give us a whole new perspective on this gas-giant world,” said Bolton.

“It will take days for all the science data collected during the flyby to be downlinked and even more to begin to comprehend what Juno and Jupiter are trying to tell us.”

The prime mission is scheduled to end in February of 2018 with a suicide plunge into the Jovian atmosphere to prevent any possible contamination with Jupiter’s potentially habitable moons such as Europa and Ganymede.

“No other spacecraft has ever orbited Jupiter this closely, or over the poles in this fashion,” said Steve Levin, Juno project scientist from NASA’s Jet Propulsion Laboratory in Pasadena, California. “This is our first opportunity and there are bound to be surprises. We need to take our time to make sure our conclusions are correct.”

The team did release an approach image taken by JunoCam on Aug. 23 when the spacecraft was 2.8 million miles (4.4 million kilometers) from the gas giant planet on the inbound leg of its initial 53.5-day capture orbit.

One additional long period orbit is planned. The main engine will fire again in October to reduce the orbit to the 14 day science orbit.

Animation of Juno 14-day orbits starting in late 2016.  Credits: NASA/JPL-Caltech
Animation of Juno 14-day orbits starting in late 2016. Credits: NASA/JPL-Caltech

The solar powered probe will collect unparalleled new data that will unveil the hidden inner secrets of Jupiter’s origin and evolution as it peers “beneath the obscuring cloud cover of Jupiter and study its auroras to learn more about the planet’s origins, structure, atmosphere and magnetosphere.”

The $1.1 Billion Juno was launched on Aug. 5, 2011 from Cape Canaveral Air Force Station, Florida atop the most powerful version of the Atlas V rocket augmented by 5 solid rocket boosters and built by United Launch Alliance (ULA). That same Atlas V 551 version recently launched MUOS-5 for the US Navy on June 24.

The Juno spacecraft was built by prime contractor Lockheed Martin in Denver.

Illustration of NASA's Juno spacecraft firing its main engine to slow down and go into orbit around Jupiter. Lockheed Martin built the Juno spacecraft for NASA's Jet Propulsion Laboratory.  Credit: NASA/Lockheed Martin
Illustration of NASA’s Juno spacecraft firing its main engine to slow down and go into orbit around Jupiter. Lockheed Martin built the Juno spacecraft for NASA’s Jet Propulsion Laboratory. Credit: NASA/Lockheed Martin

The last NASA spacecraft to orbit Jupiter was Galileo in 1995. It explored the Jovian system until 2003.

In the final weeks of the approach before Jupiter Orbit Insertion (JOI), JunoCam captured dramatic views of Jupiter and all four of the Galilean Moons moons — Io, Europa, Ganymede and Callisto.

At the post JOI briefing at JPL on July 5, these were combined into a spectacular JunoCam time-lapse movie released by Bolton and NASA.

Watch and be mesmerized -“for humanity, our first real glimpse of celestial harmonic motion” says Bolton.

Video caption: NASA’s Juno spacecraft captured a unique time-lapse movie of the Galilean satellites in motion about Jupiter. The movie begins on June 12th with Juno 10 million miles from Jupiter, and ends on June 29th, 3 million miles distant. The innermost moon is volcanic Io; next in line is the ice-crusted ocean world Europa, followed by massive Ganymede, and finally, heavily cratered Callisto. Galileo observed these moons to change position with respect to Jupiter over the course of a few nights. From this observation he realized that the moons were orbiting mighty Jupiter, a truth that forever changed humanity’s understanding of our place in the cosmos. Earth was not the center of the Universe. For the first time in history, we look upon these moons as they orbit Jupiter and share in Galileo’s revelation. This is the motion of nature’s harmony. Credits: NASA/JPL-Caltech/MSSS

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Ken Kremer

United Launch Alliance Atlas V liftoff with NASA’s Juno to Jupiter orbiter on Aug. 5, 2011 from Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer/kenkremer.com
United Launch Alliance Atlas V liftoff with NASA’s Juno to Jupiter orbiter on Aug. 5, 2011 from Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer/kenkremer.com