Juno Transmits 1st Orbital Imagery after Swooping Arrival Over Jovian Cloud Tops and Powering Up

This color view from NASA's Juno spacecraft is made from some of the first images taken by JunoCam after the spacecraft entered orbit around Jupiter on July 4, 2016. Credits: NASA/JPL-Caltech/SwRI/MSSS
This color view from NASA's Juno spacecraft is made from some of the first images taken by JunoCam after the spacecraft entered orbit around Jupiter on July 4, 2016.  Credits: NASA/JPL-Caltech/SwRI/MSSS
This color view from NASA’s Juno spacecraft is made from some of the first images taken by JunoCam after the spacecraft entered orbit around Jupiter on July 4, 2016. Credits: NASA/JPL-Caltech/SwRI/MSSS

NASA’s newly arrived Jovian orbiter Juno has transmitted its first imagery since reaching orbit last week on July 4 after swooping over Jupiter’s cloud tops and powering back up its package of state-of-the-art science instruments for unprecedented research into determining the origin of our solar systems biggest planet.

The breathtaking image clearly shows the well known banded cloud tops in Jupiter’s atmosphere as well as the famous Great Red Spot and three of the humongous planet’s four largest moons — Io, Europa and Ganymede.

The ‘Galilean’ moons are annotated from left to right in the lead image.

Juno’s visible-light camera named JunoCam was turned on six days after Juno fired its main engine to slow down and be captured into orbit around Jupiter – the ‘King of the Planets’ following a nearly five year long interplanetary voyage from Earth.

The image was taken when Juno was 2.7 million miles (4.3 million kilometers) distant from Jupiter on July 10, at 10:30 a.m. PDT (1:30 p.m. EDT, 5:30 UTC), and traveling on the outbound leg of its initial 53.5-day capture orbit.

Juno came within only about 3000 miles of the cloud tops and passed through Jupiter’s extremely intense and hazardous radiation belts during orbital arrival over the north pole.

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 newly released JunoCam image is visible proof that Juno survived the do-or-die orbital fireworks on America’s Independence Day that placed the baskeball-court sized probe into orbit around Jupiter – and is in excellent health to carry out its groundbreaking mission to elucidate Jupiter’s ‘Genesis.’

“This scene from JunoCam indicates it survived its first pass through Jupiter’s extreme radiation environment without any degradation and is ready to take on Jupiter,” said Scott Bolton, principal investigator from the Southwest Research Institute in San Antonio, in a statement.

“We can’t wait to see the first view of Jupiter’s poles.”

Within two days of the nerve wracking and fully automated 35-minute-long Jupiter Orbital Insertion (JOI) maneuver, the Juno engineering team begun powering up five of the probes science instruments on July 6.

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

All nonessential instruments and systems had been powered down in the final days of Juno’s approach to Jupiter to ensure the maximum chances for success of the critical JOI engine firing.

“We had to turn all our beautiful instruments off to help ensure a successful Jupiter orbit insertion on July 4,” said Bolton.

“But next time around we will have our eyes and ears open. You can expect us to release some information about our findings around September 1.”

Juno resumed high data rate communications with Earth on July 5, the day after achieving orbit.

We can expect to see more JunoCam images taken during this first orbital path around the massive planet.

But the first high resolution images are still weeks away and will not be available until late August on the inbound leg when the spacecraft returns and swoops barely above the clouds.

“JunoCam will continue to take images as we go around in this first orbit,” said Candy Hansen, Juno co-investigator from the Planetary Science Institute, Tucson, Arizona, in a statement.

“The first high-resolution images of the planet will be taken on August 27 when Juno makes its next close pass to Jupiter.”

All of JunoCams images will be released to the public.

During a 20 month long science mission – entailing 37 orbits lasting 14 days each – the probe will plunge to within about 2,600 miles (4,100 kilometers) of the turbulent cloud tops.

It 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 solar powered Juno spacecraft approached Jupiter over its north pole, affording an unprecedented perspective on the Jovian system – “which looks like a mini solar system” – as it flew through the giant planets intense radiation belts in ‘autopilot’ mode.

Juno is the first solar powered probe to explore Jupiter or any outer planet.

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

At the post JOI briefing 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

The $1.1 Billion Juno was launched on Aug. 5, 2011 from Cape Canaveral, 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 just launched MUOS-5 for the US Navy on June 24.

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

The mission will end in February 2018 with an intentional death dive into the atmosphere to prevent any possibility of a collision with Europa, one of Jupiter’s moons that is a potential abode for life.

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

From Earth’s perspective, Jupiter was in conjunction with Earth’s Moon shortly after JOI during the first week in July.

Personally its thrilling to realize that an emissary from Earth is once again orbiting Jupiter after a 13 year long hiatus as seen in the authors image below – coincidentally taken the same day as JunoCam’s first image from orbit.

Juno, Jupiter and the Moon as seen from I-95 over Dunn, NC on July 10, 2016. Credit: Ken Kremer/kenkremer.com
Juno, Jupiter and the Moon as seen from I-95 over Dunn, NC on July 10, 2016. Credit: Ken Kremer/kenkremer.com

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

Ken Kremer

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Learn more about Juno at Jupiter, SpaceX CRS-9 rocket launch, ISS, ULA Atlas and Delta rockets, Orbital ATK Cygnus, Boeing, Space Taxis, Mars rovers, Orion, SLS, Antares, NASA missions and more at Ken’s upcoming outreach events:

July 15-18: “SpaceX launches to ISS on CRS-9, Juno at Jupiter, ULA Delta 4 Heavy spy satellite, SLS, Orion, Commercial crew, Curiosity explores Mars, Pluto and more,” Kennedy Space Center Quality Inn, Titusville, FL, evenings

NASA's Juno probe captured the image data for this composite picture during its Earth flyby on Oct. 9 over Argentina,  South America and the southern Atlantic Ocean. Raw imagery was reconstructed and aligned by Ken Kremer and Marco Di Lorenzo, and false-color blue has been added to the view taken by a near-infrared filter that is typically used to detect methane. Credit: NASA/JPL/SwRI/MSSS/Ken Kremer/Marco Di Lorenzo
NASA’s Juno probe captured the image data for this composite picture during its Earth flyby on Oct. 9 over Argentina, South America and the southern Atlantic Ocean. Raw imagery was reconstructed and aligned by Ken Kremer and Marco Di Lorenzo, and false-color blue has been added to the view taken by a near-infrared filter that is typically used to detect methane. Credit: NASA/JPL/SwRI/MSSS/Ken Kremer/Marco Di Lorenzo

Welcome to Jupiter – NASA’s Juno Achieves Orbit around ‘King of the Planets’

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.
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

Welcome to Jupiter! NASA’s Juno spacecraft is orbiting Jupiter at this moment!

“NASA did it again!” pronounced an elated Scott Bolton, investigator of Juno from Southwest Research Institute in San Antonio, to loud cheers and applause from the overflow crowd of mission scientists and media gathered at the post orbit media briefing at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

After a nearly five year journey covering 1.7-billion-miles (2.8-billion-kilometers) across our solar system, NASA’s basketball court-sized Juno orbiter achieved orbit around Jupiter, the ‘King of the Planets’ late Monday night, July 4, in a gift to all Americans on our 240th Independence Day and a gift to science to elucidate our origins.

“We are in orbit and now the fun begins, the science,” said Bolton at the briefing. “We just did the hardest thing NASA’s ever done! That’s my claim. I am so happy … and proud of this team.”

And the science is all about peering far beneath the well known banded cloud tops for the first time to investigate Jupiter’s deep interior with a suite of nine instruments, and discover the mysteries of its genesis and evolution and the implications for how we came to be.

“The deep interior of Jupiter is nearly unknown. That’s what we are trying to learn about. The origin of us.”

Solar powered Juno successfully entered a polar elliptical orbit around Jupiter after completing a must-do 35-minute-long firing of the main engine known as Jupiter Orbital Insertion or JOI.

The spacecraft approached Jupiter over its north pole, affording an unprecedented perspective on the Jovian system – “which looks like a mini solar system” – as it flew through the giant planets intense radiation belts in ‘autopilot’ mode.

“The mission team did great. The spacecraft did great. We are looking great. It’s a great day,” Bolton gushes.

Engineers tracking the telemetry received confirmation that the JOI burn was completed as planned at 8:53 p.m. PDT (11:53 p.m. EDT) Monday, July 4.

Juno is only the second probe from Earth to orbit Jupiter and the first solar powered probe to the outer planets. The gas giant is two and a half times more massive than all of the other planets combined.

“Independence Day always is something to celebrate, but today we can add to America’s birthday another reason to cheer — Juno is at Jupiter,” said NASA administrator Charlie Bolden in a statement.

“And what is more American than a NASA mission going boldly where no spacecraft has gone before? With Juno, we will investigate the unknowns of Jupiter’s massive radiation belts to delve deep into not only the planet’s interior, but into how Jupiter was born and how our entire solar system evolved.”

Artists concept NASA's Juno spacecraft firing its main engine to slow down and go into orbit around Jupiter on July 4, 2016 nearly five years after launch.   Credit: NASA
Artists concept NASA’s Juno spacecraft firing its main engine to slow down and go into orbit around Jupiter on July 4, 2016 nearly five years after launch. Credit: NASA

The do-or-die burn of Juno’s 645-Newton Leros-1b main engine started at 8:18 p.m. PDT (11:18 p.m. EDT), which had the effect of decreasing the spacecraft’s velocity by 1,212 miles per hour (542 meters per second) and allowing Juno to be captured in orbit around Jupiter. There were no second chances.

All of the science instruments were turned off on June 30 to keep the focus on the nail-biting insertion maneuver and preserve battery power, said Bolton.

“So tonight through tones Juno sang to us. And it was a song of perfection. After a 1.7 billion mile journey we hit tour burn targets within one second,” Rick Nybakken, Juno project manager from JPL, gleefully reported at the briefing.

“That’s how good our team is! And that’s how well our Juno spacecraft performed tonight.”

To accomplish the burn, the spacecraft first had to adjust it’s attitude to point the engine in the required direction to slow the spacecraft and then simultaneously also had the effect that the life giving solar panels were pointing away from the sun. It the only time during the entire mission at Jupiter that the solar panels were in darkness and not producing energy.

The spacecraft’s rotation rate was also spun up from 2 to 5 revolutions per minute (RPM) to help stabilize it during JOI. Juno is spin stabilized to maintain pointing.

After the burn was complete, Juno was spun down and adjusted to point to the sun before it ran out of battery power.

We have to get the blood flowing through Juno’s veins, Bolton emphasized.

It is equipped with 18,698 individual solar cells over 60 square meters of surface on the solar arrays to provide energy. Juno is spinning like a windmill through space with its 3 giant solar arrays. It is about 540 million miles (869 million kilometers) from Earth.

Juno mission briefing on  July 5, 2016 at JPL after the successful JOI orbit insertion on July 4.  Credit: Roland Keller/rkeusa.blogspot.com
Juno mission briefing on July 5, 2016 at JPL after the successful JOI orbit insertion on July 4. Credit: Roland Keller/rkeusa.blogspot.com

Signals traveling at the speed of light take 48 minutes to reach Earth, said Nybakken.

So the main engine burn, which was fully automated, was already over for some 13 minutes before the first indications of the outcome reach Earth via a series of Doppler signals and tones.

“Tonight, 540 million miles away, Juno performed a precisely choreographed dance at blazing speeds with the largest, most intense planet in our solar system,” said Guy Beutelschies, director of Interplanetary Missions at Lockheed Martin Space Systems.

“Since launch, Juno has operated exceptionally well, and the flawless orbit insertion is a testament to everyone working on Juno and their focus on getting this amazing spacecraft to its destination. NASA now has a science laboratory orbiting Jupiter.”

“The spacecraft is now pointed back at the sun and the antenna back at Earth. The spacecraft performed well and did everything it needed to do,” he reported at the briefing.

“We are looking forward to getting all that science data to Scott and the team.”

“Juno is also the farthest mission to rely on solar power. And although they provide only 1/25th the power at Earth, they still provide over 500 watts of power at Jupiter,” said Nybakken.

Initially the spacecraft enters a long, looping polar orbit lasting about 53 days. That highly elliptical orbit will be trimmed to 14 days for the regular science orbits.

The orbits are designed to minimize contact with Jupiter’s extremely intense radiation belts. The nine science instruments are shielded inside a ½ thick vault built of Titanium to protect them from the utterly deadly radiation of some 20,000,000 rads.

During a 20 month long science mission – entailing 37 orbits lasting 14 days each – the probe will plunge to within about 3000 miles of the turbulent cloud tops and collect unprecedented new data that will unveil the hidden inner secrets of Jupiter’s origin and evolution.

But the length and number of the science orbits has changed since the mission was launched almost 5 years ago in 2011.

Originally Juno was planned to last about one year with an orbital profile involving 33 orbits of 11 days each.

I asked the team to explain the details of how and why the change from 11 to 14 days orbits and increasing the total number of orbits to 37 from 33, especially in light of the extremely harsh radiation hazards?

“The original plan of 33 orbits of 11 days was an example but there were other periods that would work,” Bolton told Universe Today.

“What we really cared about was dropping down over the poles and capturing each longitude, and laying a map or net around Jupiter.”

“Also, during the Earth flyby we went into safe mode. And as we looked at that it was a hiccup by the spacecraft but it actually behaved as it should have.”

“So we said well if that happened at Jupiter we would like to be able to recover and not lose an orbit. So we started to look at the timeline of how long it took to recover, and did we want to add a couple of days to the orbit for conservatism – to ensure the science mission.”

“So it made sense to add 3 days. It didn’t change the science and it made the probability of success even greater. So that was the basis of the change.”

“We also evaluated the radiation. And it wasn’t much different. Juno is designed to take data at a very low risk. The radiation slowly accumulates at the start. As you get to the later part of the mission, it gets a faster and faster accumulation.”

“So we still retained that conservatism as well and the overall radiation dose was pretty much the same,” Bolton explained.

“The radiation we accumulate is not just the more time you spend the more radiation,” Steve Levin, Juno Project Scientist at JPL, told Universe Today.

“Each time we come in close to the planet we get a dose of radiation. Then the spacecraft is out far from Jupiter and is relatively free from that radiation until we come in close again.”

“So just changing from 11 to 14 day orbits does not mean we get more radiation because you are there longer.”

“It’s really the number of times we come in close to Jupiter that determines how much radiation we are getting.”

Juno is the fastest spacecraft ever to arrive at Jupiter and was moving at over 165,000 mph relative to Earth and 130,000 mph relative to Jupiter at the moment of JOI.

Juno’s principal goal is to understand the origin and evolution of Jupiter.

“With its suite of nine science instruments, Juno will investigate the existence of a solid planetary core, map Jupiter’s intense magnetic field, measure the amount of water and ammonia in the deep atmosphere, and observe the planet’s auroras. The mission also will let us take a giant step forward in our understanding of how giant planets form and the role these titans played in putting together the rest of the solar system. As our primary example of a giant planet, Jupiter also can provide critical knowledge for understanding the planetary systems being discovered around other stars,” according to a NASA description.

The $1.1 Billion Juno was launched on Aug. 5, 2011 from Cape Canaveral, 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 just launched MUOS-5 for the US Navy on June 24.

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

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

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

Bolton also released new views of Jupiter taken by JunoCam – the on board public outreach camera that snapped a final gorgeous view of the Jovian system showing Jupiter and its four largest moons, dancing around the largest planet in our solar system.

The newly released color image was taken on June 29, 2016, at a distance of 3.3 million miles (5.3 million kilometers) from Jupiter – just before the probe went into autopilot mode.

This is the final view taken by the JunoCam instrument on NASA's Juno spacecraft before Juno's instruments were powered down in preparation for orbit insertion. Juno obtained this color view on June 29, 2016, at a distance of 3.3 million miles (5.3 million kilometers) from Jupiter.  See timelapse movie below.  Credits: NASA/JPL-Caltech/MSSS
This is the final view taken by the JunoCam instrument on NASA’s Juno spacecraft before Juno’s instruments were powered down in preparation for orbit insertion. Juno obtained this color view on June 29, 2016, at a distance of 3.3 million miles (5.3 million kilometers) from Jupiter. See timelapse movie below. Credits: NASA/JPL-Caltech/MSSS

It shows a dramatic view of the clouds bands of Jupiter, dominating a spectacular scene that includes the giant planet’s four largest moons — Io, Europa, Ganymede and Callisto.

Scott Bolton and NASA also released this spectacular new time-lapse JunoCam movie at today’s briefing showing Juno’s approach to Jupiter and the Galilean Moons.

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 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

Along the 5 year journey to Jupiter, Juno made a return trip to Earth on Oct. 9, 2013 for a flyby gravity assist speed boost that enabled the trek to the Jovian system.

During the Earth flyby (EFB), the science team observed Earth using most of Juno’s nine science instruments including, JunoCam, since the slingshot also served as an important dress rehearsal and key test of the spacecraft’s instruments, systems and flight operations teams.

The JunoCam images will be made publicly available to see and process.

During the Earth flyby, Junocam snapped some striking images of Earth as it sped over Argentina, South America and the South Atlantic Ocean and came within 347 miles (560 kilometers) of the surface.

For example a dazzling portrait of our Home Planet high over the South American coastline and the Atlantic Ocean gives a hint of what’s to come from Jupiter’s cloud tops. See our colorized Junocam mosaic of land, sea and swirling clouds, created by Ken Kremer and Marco Di Lorenzo

This colorized composite shows more than half of Earth’s disk over the coast of Argentina and the South Atlantic Ocean as the Juno probe slingshotted by on Oct. 9, 2013 for a gravity assisted acceleration to Jupiter. The mosaic was assembled from raw images taken by the Junocam imager. Credit: NASA/JPL/SwRI/MSSS/Ken Kremer/Marco Di Lorenzo
This colorized composite shows more than half of Earth’s disk over the coast of Argentina and the South Atlantic Ocean as the Juno probe slingshotted by on Oct. 9, 2013 for a gravity assisted acceleration to Jupiter. The mosaic was assembled from raw images taken by the Junocam imager. Credit: NASA/JPL/SwRI/MSSS/Ken Kremer/Marco Di Lorenzo

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

Ken Kremer

Rick Nybakken, Juno project manager at JPL illustrates how Juno will enter orbit around Jupiter during Juno mission briefing on July 4, 2016 at JPL. Credit: Roland Keller/rkeusa.blogspot.com
Rick Nybakken, Juno project manager at JPL illustrates how Juno will enter orbit around Jupiter during Juno mission briefing on July 4, 2016 at JPL. Credit: Roland Keller/rkeusa.blogspot.com

Juno Snaps Final View of Jovian System Ahead of ‘Independence Day’ Orbital Insertion Fireworks Tonight – Watch Live

This is the final view taken by the JunoCam instrument on NASA's Juno spacecraft before Juno's instruments were powered down in preparation for orbit insertion. Juno obtained this color view on June 29, 2016, at a distance of 3.3 million miles (5.3 million kilometers) from Jupiter. See timelapse movie below. Credits: NASA/JPL-Caltech/MSSS
This is the final view taken by the JunoCam instrument on NASA's Juno spacecraft before Juno's instruments were powered down in preparation for orbit insertion. Juno obtained this color view on June 29, 2016, at a distance of 3.3 million miles (5.3 million kilometers) from Jupiter.  Credit:  Credits: NASA/JPL-Caltech/MSSS
This is the final view taken by the JunoCam instrument on NASA’s Juno spacecraft before Juno’s instruments were powered down in preparation for orbit insertion. Juno obtained this color view on June 29, 2016, at a distance of 3.3 million miles (5.3 million kilometers) from Jupiter. See timelapse movie below. Credits: NASA/JPL-Caltech/MSSS

After a nearly 5 year odyssey across the solar system, NASA’s solar powered Juno orbiter is all set to ignite its main engine late tonight and set off a powerful charge of do-or-die fireworks on America’s ‘Independence Day’ required to place the probe into orbit around Jupiter – the ‘King of the Planets.’

To achieve orbit, Juno must will perform a suspenseful maneuver known as ‘Jupiter Orbit Insertion’ or JOI tonight, Monday, July 4, upon which the entire mission and its fundamental science hinges. There are no second chances!

You can be part of all the excitement and tension building up to and during that moment, which is just hours away – and experience the ‘Joy of JOI’ by tuning into NASA TV tonight!

Watch the live webcast on NASA TV featuring the top scientists and NASA officials starting at 10:30 p.m. EDT (7:30 p.m. PST, 0230 GMT) – direct from NASA’s Jet Propulsion Laboratory: https://www.nasa.gov/nasatv

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.
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

And for a breathtaking warm-up act, Juno’s on board public outreach JunoCam camera snapped a final gorgeous view of the Jovian system showing Jupiter and its four largest moons, dancing around the largest planet in our solar system.

The newly released color image was taken on June 29, 2016, at a distance of 3.3 million miles (5.3 million kilometers) from Jupiter – just before the probe went into autopilot mode.

It shows a dramatic view of the clouds bands of Jupiter, dominating a spectacular scene that includes the giant planet’s four largest moons — Io, Europa, Ganymede and Callisto.

NASA also released this new time-lapse JunoCam movie today:

Video caption: Juno’s Approach to Jupiter: After nearly five years traveling through space to its destination, NASA’s Juno spacecraft will arrive in orbit around Jupiter on July 4, 2016. This video shows a peek of what the spacecraft saw as it closed in on its destination. Credits: NASA/JPL-Caltech/MSSS

The spacecraft is approaching Jupiter over its north pole, affording an unprecedented perspective on the Jovian system – “which looks like a mini solar system,” said Juno Principal Investigator and chief scientist Scott Bolton, from the Southwest Research Institute (SwRI) in San Antonio, Tx, at today’s media briefing at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

“The deep interior of Jupiter is nearly unknown. That’s what we are trying to learn about.”

The 35-minute-long main engine burn is preprogrammed to start at 11:18 p.m. EDT (8:18 p.m. PST, 0318 GMT). It is scheduled to last until approximately 11:53 p.m. (8:53 p.m. PST, 0353 GMT).

Juno mission briefing July 4, 2016 at JPL by Jim Green, Scott Bolton, Rick Nybakken and Heidi Becker.  Credit: Roland Keller
Juno mission briefing July 4, 2016 at JPL by Jim Green, Scott Bolton, Rick Nybakken and Heidi Becker. Credit: Roland Keller/rkeusa.blogspot.com

All of the science instruments were turned off on June 30 to keep the focus on the nail-biting insertion maneuver and preserve battery power, said Bolton. Solar powered Juno is pointed away from the sun during the engine firing.

JOI is required to slow the spacecraft so it can be captured into the gas giant’s orbit as it closes in over the north pole.

Initially the spacecraft will enter a long, looping polar orbit lasting about 53 days. That highly elliptical orbit will quickly be trimmed to 14 days for the science orbits.

The orbits are designed to minimize contact with Jupiter’s extremely intense radiation belts. The science instruments are shielded inside a ½ thick vault built of Titanium to protect them from the utterly deadly radiation – of some 20,000,000 rads.

Artist's concept of NASA's Juno spacecraft crossing the orbits of Jupiter's four largest moons -- Callisto, Gaynmede, Europa and Io -- on its approach to Jupiter. Credits: NASA/JPL-Caltech
Artist’s concept of NASA’s Juno spacecraft crossing the orbits of Jupiter’s four largest moons — Callisto, Gaynmede, Europa and Io — on its approach to Jupiter.
Credits: NASA/JPL-Caltech

Juno is the fastest spacecraft ever to arrive at Jupiter and is moving at over 165,000 mph relative to Earth and 130,000 mph relative to Jupiter.

After a five-year and 2.8 Billion kilometer (1.7 Billion mile) outbound trek to the Jovian system and the largest planet in our solar system and an intervening Earth flyby speed boost, the moment of truth for Juno is now inexorably at hand.

Signals traveling at the speed of light take 48 minutes to reach Earth, said Rick Nybakken, Juno project manager from NASA’s Jet Propulsion Laboratory, at the media briefing.

So the main engine burn, which is fully automated, will already be over for some 13 minutes before the first indications of the outcome reach Earth via a series of Doppler shifts and tones. It is about 540 million miles (869 million kilometers) from Earth.

“By the time the burn is complete, we won’t even hear about it until 13 minutes later.”

“The engine burn will slow Juno by 542 meters/second (1,212 mph) and is fully automated as it approaches over Jupiter’s North Pole,” explained Nybakken.

“The long five year cruise enabled us to really learn about the spacecraft and how it operates.”

As it travels through space, the basketball court sized Juno is spinning like a windmill with its 3 giant solar arrays.

“Juno is also the farthest mission to rely on solar power. The solar panels are 60 square meters in size. And although they provide only 1/25th the power at Earth, they still provide over 500 watts of power at Jupiter.”

Rick Nybakken, Juno project manager at JPL illustrates how Juno will enter orbit around Jupiter during Juno mission briefing on July 4, 2016 at JPL. Credit: Roland Keller
Rick Nybakken, Juno project manager at JPL illustrates how Juno will enter orbit around Jupiter during Juno mission briefing on July 4, 2016 at JPL. Credit: Roland Keller/rkeusa.blogspot.com

The protective cover that shields Juno’s main engine from micrometeorites and interstellar dust was opened on June 20.

During a 20 month long science mission – entailing 37 orbits lasting 14 days each – the probe will plunge to within about 3000 miles of the turbulent cloud tops and collect unprecedented new data that will unveil the hidden inner secrets of Jupiter’s origin and evolution.

“Jupiter is the Rosetta Stone of our solar system,” says Bolton. “It is by far the oldest planet, contains more material than all the other planets, asteroids and comets combined and carries deep inside it the story of not only the solar system but of us. Juno is going there as our emissary — to interpret what Jupiter has to say.”

During the orbits, Juno will probe 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, 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 just launched MUOS-5 for the US Navy on June 24.

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

Juno soars skyward to Jupiter on Aug. 5, 2011 from launch pad 41 at Cape Canaveral Air Force Station at 12:25 p.m. EDT. View from the VAB roof. Credit: Ken Kremer/kenkremer.com
Juno soars skyward to Jupiter on Aug. 5, 2011 from launch pad 41 at Cape Canaveral Air Force Station at 12:25 p.m. EDT. View from the VAB roof. Credit: Ken Kremer/kenkremer.com

Along the way Juno made a return trip to Earth on Oct. 9, 2013 for a flyby gravity assist speed boost that enabled the trek to Jupiter.

The flyby provided 70% of the velocity compared to the Atlas V launch, said Nybakken.

During the Earth flyby (EFB), the science team observed Earth using most of Juno’s nine science instruments since the slingshot also serves as an important dress rehearsal and key test of the spacecraft’s instruments, systems and flight operations teams.

Juno also went into safe mode – something the team must avoid during JOI.

What lessons were learned from the safe mode event and applied to JOI, I asked?

“We had the battery at 50% state of charge during the EFB and didn’t accurately predict the sag on the battery when we went into eclipse. We now have a validated high fidelity power model which would have predicted that sag and we would have increased the battery voltage,” Nybakken told Universe Today

“It will not happen at JOI as we don’t go into eclipse and are at 100% SOC. Plus the instruments are off which increases our power margins.”

Junocam also took some striking images of Earth as it sped over Argentina, South America and the South Atlantic Ocean and came within 347 miles (560 kilometers) of the surface.

For example the dazzling portrait of our Home Planet high over the South American coastline and the Atlantic Ocean.

For a hint of what’s to come, see our colorized Junocam mosaic of land, sea and swirling clouds, created by Ken Kremer and Marco Di Lorenzo

NASA's Juno probe captured the image data for this composite picture during its Earth flyby on Oct. 9 over Argentina,  South America and the southern Atlantic Ocean. Raw imagery was reconstructed and aligned by Ken Kremer and Marco Di Lorenzo, and false-color blue has been added to the view taken by a near-infrared filter that is typically used to detect methane. Credit: NASA/JPL/SwRI/MSSS/Ken Kremer/Marco Di Lorenzo
NASA’s Juno probe captured the image data for this composite picture during its Earth flyby on Oct. 9 over Argentina, South America and the southern Atlantic Ocean. Raw imagery was reconstructed and aligned by Ken Kremer and Marco Di Lorenzo, and false-color blue has been added to the view taken by a near-infrared filter that is typically used to detect methane. Credit: NASA/JPL/SwRI/MSSS/Ken Kremer/Marco Di Lorenzo

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

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

Ken Kremer

Infographic about Juno’s Jupiter Orbit Insertion (JOI) maneuver on July 4, 2016.   Credit: NASA/Lockheed Martin
Infographic about Juno’s Jupiter Orbit Insertion (JOI) maneuver on July 4, 2016. Credit: NASA/Lockheed Martin