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Raumfahrt - JUNO SPACECRAFT-Jupiter-Mission Update-1

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5.01.2013

View of Juno’s position on Jan. 4 from Eyes on the Solar System.

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As of Jan. 4, Juno was approximately 180 million miles (290 million kilometers) from Earth, with a one-way radio signal travel time of approximately 16 minutes. The spacecraft has now traveled 583 million miles (938 million kilometers, or 6.27 AU) since launch. Juno is currently traveling at a velocity of 11 miles (17 kilometers) per second relative to the sun. Velocity relative to Earth is 21 miles (34 kilometers) per second.

The Juno spacecraft is in excellent health and is operating nominally. Four instruments -- JEDI, MWR, Waves, and MAG -- are turned on.

Most recent spacecraft significant events

Juno is currently headed back toward the inner solar system for a planned Earth flyby gravity assist maneuver on Oct. 9, 2013. The gravity assist will give the spacecraft the boost it needs to reach Jupiter, where it is slated to arrive in July 2016.

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NASA's Juno Spacecraft Images Big Dipper

NASA’s Jupiter-bound Juno spacecraft tested its JunoCam instrument on one of the icons of the night sky – the Big Dipper. Image credit: NASA/JPL-Caltech/SWRI/MSSS

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In England it is known as the "Plough," in Germany the "Great Cart," and in Malaysia the "Seven Ploughs." Since humanity first turned its eyes skyward, the seven northern hemisphere stars that compose the "Big Dipper" have been a welcome and familiar introduction to the heavens.

"I can recall as a kid making an imaginary line from the two stars that make up the right side of the Big Dipper's bowl and extending it upward to find the North Star," said Scott Bolton, principal investigator of NASA's Juno mission to Jupiter from the Southwest Research Institute in San Antonio. "Now, the Big Dipper is helping me make sure the camera aboard Juno is ready to do its job."

Launched on Aug. 5, 2011, the solar-powered Juno spacecraft is 279 days and 380 million miles (612 million kilometers) into its five-year, 1,905-million-mile (3,065-million-kilometer) journey to Jupiter. Once there, the spacecraft will orbit the planet's poles 33 times and use its nine instruments to image and probe beneath the gas giant's obscuring cloud cover to learn more about Jupiter's origins, structure, atmosphere and magnetosphere, and look for a potential solid planetary core.

One of those instruments, JunoCam, is tasked with taking closeups of the gas giant's atmosphere. But, with four-and-a-half years to go before photons of light from Jupiter first fill its CCD (charge-coupled device), and a desire to certify the camera in flight, Juno's mission planners took a page from their childhood and on March 21, aimed their camera at a familiar celestial landmark.

"I don't know if it’s the first space-based image of the Big Dipper but, as it was taken when we were well beyond Mars orbit, it's probably from the farthest out," said Bolton. "But much more important than that is the simple fact that JunoCam, like the rest of this mission, works as advertised and is ready for its day in the sun – around Jupiter."

Juno's name comes from Greek and Roman mythology. The god Jupiter drew a veil of clouds around himself to hide his mischief, and his wife, the goddess Juno, was able to peer through the clouds and reveal Jupiter's true nature.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. JunoCam was developed and is operated by Malin Space Science Systems in San Diego. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of the California Institute of Technology in Pasadena.

 

Quelle: NASA

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Update: 21.02.2013

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Quelle: NASA

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Update: 5.05-2013

 

PASADENA -- On its way to Jupiter, NASA's Juno spacecraft will fly past a surprising place later this year: Earth.

NASA launched the satellite in 2011 to a region of space just past Mars, but it's boomeranging back to this planet to get a gravity assist for its final journey to Jupiter. When it flies past on Oct. 9, the Earth's gravity will boost Juno like a slingshot, a technique that helps save fuel and money.

"A year ago ... we did two main engine burns" to curve back around toward Earth, said former mission manager Steve Matousek of Jet Propulsion Laboratory, speaking at Caltech last week. "Then after that, it takes less than three years to get to Jupiter. On the other end, you have to slow down. "

Once it gets there in 2016, Juno will begin a polar orbit around Jupiter for about a year, circling 32 times. Scientists hope the spacecraft can answer questions about the gas giant's cloudy interior and possibly reveal the planet's role in the formation of the solar system.

Juno is carrying instruments that will help it peer underneath the gaseous surface of hydrogen and helium that keeps Jupiter's interior shrouded in mystery and will be able to detect if there's a rocky core and water deep within the planet.

"There has to be water vapor there - it's been seen experimentally from the Earth - but where is it and how much is it?" Matousek said. "Juno is designed to see globally how much


 

water vapor there is. "

The mission will only last a year because Jupiter's gravity affects the spacecraft's orbit, increasing the amount of radiation that hits Juno's equipment. It's the same problem that affected NASA's previous mission to Jupiter, Galileo, which arrived in 1995.

Engineers also kept Jupiter's moons in mind when designing the mission, particularly the one scientists are most interested in exploring, Europa.

"In the future we want to send a mission to Europa," Matousek said. "There's a very small probability that if Juno went uncontrolled ... over time you get a probability that you're going to encounter Europa,"

To prevent that, the mission will end with Juno making a controlled descent into Jupiter and burning up in the atmosphere.

But there will be plenty of chances to get excited about seeing Juno fly by this year (though it might not be seen from the U.S.), and when it arrives at Jupiter around July 4, 2016.

"Fireworks will be going off over the Rose Bowl," Matousek said.


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Quelle: NASA

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Update: 12.08.2013

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NASA's Juno is Halfway to Jupiter

PASADENA, Calif. - NASA's Juno spacecraft is halfway to Jupiter. The Jovian-system-bound spacecraft reached the milestone today (8/12/13) at 5:25 a.m. PDT (8:25 a.m. EDT/12:25 UTC).

"Juno's odometer just clicked over to 9.464 astronomical units," said Juno Principal Investigator Scott Bolton, of the Southwest Research Institute in San Antonio.  "The team is looking forward, preparing for the day we enter orbit around the most massive planet in our solar system."

For those astronomical-unitly challenged, an astronomical unit (AU) is a unit of measure used by space engineers and scientists when discussing the massive distances involved in the exploration of our solar system – and beyond.  An AU is based on the distance between Earth and the sun and is 92,955,807.273 miles (149,597,870.7 kilometers) long.  The 9.464 astronomical units Juno has already traveled (or still has left to go) is equivalent to 879,733,760 miles (or 1,415,794,248 kilometers).  Juno was 34.46 million miles (55.46 million kilometers) from Earth when the milestone was reached.

The next milestone in the nearly five-year journey to Jupiter will occur this October, when the spacecraft flies past Earth in search of a little extra speed.

"On Oct. 9, Juno will come within 347 miles (559 kilometers) of Earth," said the mission's Project Manager Rick Nybakken of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "The Earth flyby will give Juno a kick in the pants, boosting its velocity by 16,330 mph (about 7.3 kilometers per second). From there, it's next stop Jupiter."  

Juno will arrive at Jupiter on July 4, 2016, at 7:29 p.m. PDT (10:29 p.m. EDT).

Juno was launched on Aug. 5, 2011. Once in orbit around Jupiter, the spacecraft will circle the planet 33 times, from pole to pole, and use its collection of eight science instruments to probe beneath the gas giant's obscuring cloud cover. Juno's science team will learn about Jupiter's origins, structure, atmosphere and magnetosphere, and look for a potential solid planetary core.

Juno's name comes from Greek and Roman mythology. The god Jupiter drew a veil of clouds around himself to hide his mischief, and his wife, the goddess Juno, was able to peer through the clouds and reveal Jupiter's true nature.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of the California Institute of Technology in Pasadena.

Quelle: NASA

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Update: 4.10.2013

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JUNO SPACECRAFT TO FLY BY EARTH: Here's some news you might not hear from NASA because, like much of the US government, the space agency is closed. NASA's Juno spacecraft will slingshot past Earth on October 9th for a velocity boost en route to Jupiter. At closest approach the spacecraft will be only 347 miles from Earth as it gains an extra 16,000 mph for the long journey ahead. Update: During the flyby, Juno's science instruments will sample the Earth environment--a practice run for data-taking at Jupiter years from now. Fortunately, commands to activate Juno's sensors were uploaded before the shutdown. The science experiment can proceed. Radio amateurs are encouraged to beam a message to Juno during the flyby. Juno will be listening.

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Update: 9.10.2013

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Juno Careening to Earth for Critical Flyby Boost and Cool Movie Making on Oct. 9
Trajectory Map of Juno’s Earth Flyby on Oct. 9, 2013
The Earth gravity assist is required to accelerate Juno’s arrival at Jupiter on July 4, 2016 and will capture an unprecedented movie of the Earth/Moon system. Credit: NASA/JPL
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NASA’s solar powered Jupiter-bound Juno orbiter is careening towards Earth for an absolutely critical gravity assisted fly by speed boost while capturing an unprecedented movie view of the Earth/Moon system – on its ultimate quest to unveiling Jupiter’s genesis!
“Juno will flyby Earth on October 9 to get a gravity boost and increase its speed in orbit around the Sun so that it can reach Jupiter on July 4, 2016,” Juno chief scientist Dr. Scott Bolton told Universe Today in an exclusive new Juno mission update – as the clock is ticking to zero hour. “The closest approach is over South Africa.”
All this ‘high frontier’ action comes amidst the utterly chaotic US government partial shutdown, that threatened the launch of the MAVEN Mars orbiter, has halted activity on many other NASA projects and stopped public announcements of the safe arrival of NASA’s LADEE lunar orbiter on Oct. 6, Juno’s flyby and virtually everything else related to NASA!
Bolton confirmed that the shutdown fortunately hasn’t altered or killed Juno’s flyby objectives. And ops teams at prime contractor Lockheed Martin have rehearsed and all set.
And some more good news is that Slooh will track the Juno Earth Flyby “LIVE” – for those hoping to follow along. Complete details below!
“The shutdown hasn’t affected our operations or plans, Bolton told me. Bolton is Juno’s principal investigator from the Southwest Research Institute (SwRI), San Antonio, Texas.
“Juno is 100% healthy.”
“But NASA is unable to participate in our public affairs and press activities,” Bolton elaborated.
97% of NASA’s employees are furloughed – including public affairs – due to the legal requirements of the shutdown!
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Juno will also capture an unprecedented new movie of the Earth/Moon system.
A full up science investigation of our Home Planet by Juno is planned, that will also serve as a key test of the spacecraft and its bevy of state of the art instruments.
“During the earth flyby we have most of our instruments on and will obtain a unique movie of the Earth Moon system on our approach.
“We will also calibrate instuments and measure earth’s magnetosphere, obtain closeup images of the Earth and the Moon in UV [ultraviolet] and IR [infrared],” Bolton explained to Universe Today.
The flyby will accelerate the spacecraft’s velocity by 16,330 mph.
Where is the best view of Juno’s flyby, I asked?
NASA’s Juno spacecraft blasted off atop an Atlas V rocket two years ago from Cape Canaveral Air Force Station, FL, on Aug. 5, 2011 to begin a 2.8 billion kilometer science trek to discover the genesis of Jupiter hidden deep inside the planet’s interior.
Juno is on a 5 year and 1.7 Billion mile (2.8 Billion km) trek to the largest planet in our solar system. When it arrives at Jupiter on July 4, 2016, Juno will become the first polar orbiting spacecraft at the gas giant.
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Juno’s flight track above Earth during Oct. 9, 2013 flyby. Credit: NASA/JPL
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During a one year science mission – entailing 33 orbits lasting 11 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 genesis and evolution.
The goal is to find out more about the planets origins, interior structure and atmosphere, observe the aurora, map the intense magnetic field and investigate the existence of a solid planetary core
Why does Juno need a speed boost from Earth?
“A direct mission to Jupiter would have required about 50 percent more fuel than we loaded,” said Tim Gasparrini, Juno program manager for Lockheed Martin Space Systems, in a statement.
“Had we not chosen to do the flyby, the mission would have required a bigger launch vehicle, a larger spacecraft and would have been more expensive.”
Viewers near Cape Town, South Africa will have the best opportunity to view the spacecraft traveling across the sky.
Juno itself will most likely not be visible to the unaided eye, but binoculars or a small telescope with a wide field should provide an opportunity to view, according to a Slooh statement.
Slooh will track Juno live on October 9th, 2013.
Check here for international starting times: http://goo.gl/7ducFs – and for the Slooh broadcast hosted by Paul Cox.
Viewers can view the event live on Slooh.com using their computer or mobile device, or by downloading the free Slooh iPad app in the iTunes store. Questions can be asked during the broadcast via Twitter by using the hashtag #nasajuno -says Slooh.
Amidst the government shutdown, Juno prime contractor Lockheed Martin is working diligently to ensure the mission success.
Because there are NO 2nd chances!
“The team is 100 percent focused on executing the Earth flyby successfully,” said Gasparrini.
“We’ve spent a lot of time looking at possible off-nominal conditions. In the presence of a fault, the spacecraft will stay healthy and will perform as planned.”
Stay tuned here for continuing Juno, LADEE, MAVEN and more up-to-date NASA news.
And be sure to check back here for my post-flyby update.
What’s not at all clear is whether Juno will detect any signs of ‘intelligent life’ in Washington D.C.!
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Update: 10.10.2013

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JUNO SPACECRAFT PHOTOGRAPHED:

 

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Yesterday, NASA's Juno spacecraft buzzed Earth only 347 miles above our planet's surface. It was a slingshot maneuver designed to gain velocity for Juno's long trip to Jupiter (ETA: 2016). Although the spacecraft was very faint, several amateur astronomers managed to photograph. The spacecraft is now hurtling away from Earth at 23,500 mph. Bon voyage, Juno!

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Taken by Nick James on October 9, 2013 @ Juno spacecraft and astrometry obtained with a C11 + ST9XE

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Juno was captured an hour and 2 minutes after closest approach, just 14 degrees above the northeast horizon. Each frame is a 1 second exposure, taken between 20:23:33 and 20:24:47 UT on 09 Oct 2013. Juno was moving about the diameter of the full moon every 2 minutes and was 42,500km from the observatory at the time. Images taken with a 0.4-m Schmidt-Cassegrain telescope and Apogee Alta U47+ CCD.
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Taken by Peter Birtwhistle on October 9, 2013 @ Great Shefford Observatory (J95), Great Shefford, Berkshire, England

 

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Update: 12.10.2013

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Juno probe in safe mode, but managers optimistic about recovery



NASA's Jupiter-bound Juno spacecraft went into protective "safe mode" just 10 minutes after a low-altitude gravity-assist flyby of Earth Wednesday, but mission managers said Thursday they were back in touch with the spacecraft and optimistic about a full recovery from whatever triggered the upset.

Project Manager Rick Nybakken at the Jet Propulsion Laboratory in Pasadena, Calif., said engineers were downloading stored telemetry from the spacecraft and were developing plans to restore it to normal operation.

 
 


"We're starting now to develop a plan to bring the spacecraft back into operational status and we think putting that plan together is going to take a few days," he told CBS News in a telephone interview.

"Obviously, we need to finish downloading and reviewing the current data. The take aways, we're still in safe mode, we're still safe and we're proceeding in a very calm and deliberate manner to take care of this wonderful asset."

The centerpiece of a $1.1 billion mission, Juno was launched atop a United Launch Alliance Atlas 5 rocket from the Cape Canaveral Air Force Station, Fla., on Aug. 5, 2011. Even using the most powerful version of the workhorse rocket, Juno did not have enough energy to fly directly to Jupiter.

Instead, the solar-powered spacecraft was launched on a trajectory that carried it beyond the orbit of Mars and out into the asteroid belt before the sun's gravity finally began pulling the craft back into the inner solar system.

In September 2012, flight controllers carried out precisely timed rocket firings to slightly alter the probe's course, setting up Wednesday's gravity-assist flyby. By flying close to Earth, Juno was able to use the planet's gravity to boost its velocity enough to head out for Jupiter.

Closest approach occurred at 3:21 p.m. EDT (GMT-4) as the spacecraft passed about 350 miles above South Africa, just after entering Earth's shadow for a 19-minute-long eclipse.

Nybakken said Juno's flight computer encountered a problem of some sort 10 minutes after closest approach, triggering automatic safe mode routines designed to put the spacecraft in a stable configuration in the event of unexpected events, programming problems or malfunctions that are beyond its ability to resolve.

In safe mode, the flight computer stops executing stored commands and makes sure the spacecraft is "power positive" with its solar arrays pointed at the sun. The spacecraft then stands by for instructions from Earth.

"We've re-established communications, including full commandability, we verified we were in a safe, stable state, which means sun-pointed and getting power from the arrays as expected," Nybakken said late Thursday. "We are currently going through our diagnostic procedures to analyze the anomaly and just this morning we started downloading and reviewing the on-board engineering and science-slash-imaging data."

Juno was programmed to exercise its instruments during the flyby, capturing views of the Earth-moon system and collecting other data. Nybakken said the imaging sequence started normally and presumably all of the data was recorded on board before the event that triggered the computer's transition to safe mode.

"We're hopeful ... that we'll get all the data up to that point," he said. "But we really won't know until we get it all down and go through it."

Asked if engineers have any ideas about what caused the safe mode transition, Nybakken said "we don't like to speculate. We have some strong suspicions, but I'd rather not put those out" yet. Asked about Juno's overall health, he said the spacecraft appeared to be in good shape.

In the meantime, Juno came through the Earth fly by precisely on course to Jupiter. If all goes well, the spacecrat will brake into a polar orbit around the giant planet on July 4, 2016, kicking off a one-year 33-orbit mission to learn more about Jupiter's atmosphere and evolution.

Quelle: CBS

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NASA’s Juno Spacecraft Returns 1st Flyby images of Earth while Sailing On to Jupiter


This reconstructed day side image of Earth is one of the 1st snapshots transmitted back home by NASA’s Juno spacecraft during its speed boosting flyby on Oct. 9, 2013. See the original raw image below taken by the probes Junocam imager and methane filter at 12:06:30 PDT and an exposure time of 3.2 milliseconds. Juno was due to be flying over South America and the southern Atlantic Ocean. Credit: NASA/JPL/SwRI/MSSS/Ken Kremer

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Following the speed boosting slingshot of Earth on Wednesday, Oct. 9, that sent NASA’s Juno orbiter hurtling towards Jupiter, the probe has successfully transmitted back data and the very first flyby images despite unexpectedly going into ‘safe mode’ during the critical maneuver.

“Juno is transmitting telemetry today,” spokesman Guy Webster, of NASA’s Jet Propulsion Lab (JPL), told me in a phone interview late today (Oct. 10), as Juno continues sailing on its 2.8 Billion kilometer (1.7 Billion mile) outbound trek to the Jovian system.

The new images of Earth captured by the Junocam imager serves as tangible proof that Juno is communicating.

“Juno is still in safe mode today (Oct. 10),” Webster told Universe Today.

“Teams at mission control at JPL and Lockheed Martin are actively working to bring Juno out of safe mode. And that could still require a few days,” Webster explained.

Lockheed Martin is the prime contractor for Juno.

The initial raw images of Earth snapped by the craft’s Junocam imager were received by ground stations late today.

See above a day light image mosaic which I reconstructed and realigned based on the original raw image (see below) taken with the camera’s methane filter on Oct. 9 at 12:06:30 PDT (3:06:30 PM EST). Juno was to be flying over South America and the southern Atlantic Ocean.

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This day side raw image of Earth is one of the 1st snapshots transmitted back home today by NASA’s Juno spacecraft during its speed boosting flyby on Oct. 9, 2013. It was taken by the probes Junocam imager and methane filter at 12:06:30 PDT and an exposure time of 3.2 milliseconds. Juno was due to be flying over South America and the southern Atlantic Ocean. Credit: NASA/JPL/SwRI/MSSS

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Juno performed a crucial swingby of Earth on Wednesday that accelerated the probe by 16330 MPH to enable it to arrive in orbit around Jupiter on July 4, 2016.

However the gravity assist maneuver did not go entirely as planned.

Shortly after Wednesday’s flyby, Juno Project manager Rick Nybakken, of JPL, told me in a phone interview that Juno had entered safe mode but that the probe was “power positive and we have full command ability.”

“After Juno passed the period of Earth flyby closest approach at 12:21 PM PST [3:21 PM EDT] and we established communications 25 minutes later, we were in safe mode,” Nybakken explained.

The safe mode was triggered while Juno was in an eclipse mode, the only eclipse it will experience during its entire mission.

The Earth flyby did accomplish its objective by placing the $1.1 Billion Juno spacecraft exactly on course for Jupiter as intended.

“We are on our way to Jupiter as planned!”

“None of this affected our trajectory or the gravity assist maneuver – which is what the Earth flyby is,” Nybakken stated.

Juno’s closest approach was over South Africa at about 561 kilometers (349 miles).


During the flyby, the science team also planned to observe Earth using most of Juno’s nine science instruments since the slingshot also serves as a key test of the spacecraft systems and the flight operations teams.

Juno also was to capture an unprecedented new movie of the Earth/Moon system.

Many more images were snapped and should be transmitted in coming days that eventually will show a beautiful view of the Earth and Moon from space.

“During the earth flyby we have most of our instruments on and will obtain a unique movie of the Earth Moon system on our approach, Juno principal investigator Scott Bolton told me. Bolton is from the Southwest Research Institute (SwRI), San Antonio, Texas.

“We will also calibrate instuments and measure earth’s magnetosphere, obtain closeup images of the Earth and the Moon in UV [ultraviolet] and IR [infrared],” Bolton explained to Universe Today.

Juno is approaching the Earth from deep space, from the sunlit side.

“Juno will take never-before-seen images of the Earth-moon system, giving us a chance to see what we look like from Mars or Jupiter’” says Bolton.

Here is a description of Junocam from the developer – Malin Space Science Systems

“Like previous MSSS cameras (e.g., Mars Reconnaissance Orbiter’s Mars Color Imager) Junocam is a “pushframe” imager. The detector has multiple filter strips, each with a different bandpass, bonded directly to its photoactive surface. Each strip extends the entire width of the detector, but only a fraction of its height; Junocam’s filter strips are 1600 pixels wide and about 155 rows high. The filter strips are scanned across the target by spacecraft rotation. At the nominal spin rate of 2 RPM, frames are acquired about every 400 milliseconds. Junocam has four filters: three visible (red/green/blue) and a narrowband “methane” filter centered at about 890 nm.”

Juno launched atop an Atlas V rocket two years ago from Cape Canaveral Air Force Station, FL, on Aug. 5, 2011 on a journey to discover the genesis of Jupiter hidden deep inside the planet’s interior.

During a one year long science mission – entailing 33 orbits lasting 11 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.

Quelle: UT

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Update: 23.10.2013
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UPDATED Oct. 23: Juno exited safe mode on Friday, Oct. 18. 
As of Oct. 17, Juno was approximately 4.4 million miles (7.1 million kilometers) from Earth. The one-way radio signal travel time between Earth and Juno is currently about 24 seconds. Juno is currently traveling at a velocity of about 23.6 miles (38 kilometers) per second relative to the sun. Velocity relative to Earth is about 6.5 miles (10.4 kilometers) per second. Juno has now traveled 1.01 billion miles (1.63 billion kilometers, or 10.9 AU) since launch. 
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Juno's Earth flyby gravity assist was completed on Oct. 9. Several Juno science instruments made planned observations during the approach to Earth, including the Advanced Stellar Compass, JunoCam and Waves. These observations provided a useful opportunity to test the instruments during a close planetary encounter and ensure that they work as designed. The main goal of the flyby -- to give the spacecraft the boost it needed in order to reach Jupiter - was accomplished successfully, and the spacecraft is in good health and responding to ground controllers. 
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Soon after its closest approach to Earth, the spacecraft initiated the first of two "safe modes" that have occurred since the flyby. Safe mode is a state that the spacecraft may enter if its onboard computer perceives conditions on the spacecraft are not as expected. Onboard Juno, the safe mode turned off instruments and a few non-critical spacecraft components, and pointed the spacecraft toward the sun to ensure the solar arrays received power. The likely cause of the safe mode was an incorrect setting for a fault protection trigger for the spacecraft's battery. During the eclipse, the solar cells, as expected, were not generating electricity, and the spacecraft was drawing on the battery supply. When the voltage dropped below this fault protection trigger, the spacecraft initiated the safe mode sequence. The spacecraft acted as expected during the transition into and while in safe mode. The spacecraft exited the safe mode on Oct. 12. 
The spacecraft entered the safe mode configuration again on Sunday evening (10/13/13). When the spacecraft's onboard computer transitioned from the Earth flyby sequence to the cruise sequence, a component called the stellar reference unit remained in the Earth flyby configuration. When the spacecraft's computer saw the draw on electricity was slightly greater than expected, it did as it was programmed to do and initiated a safe mode event. 
Navigation has confirmed that Juno's current trajectory is "near-perfect" vs. planned. The mission team is in two-way communications with the spacecraft and it is operating as expected, and designed for, in safe mode. They expect to exit safe mode sometime next week. 
Juno will arrive at Jupiter on July 4, 2016, at 7:29 p.m. PDT (10:29 p.m. EDT). 
Juno was launched on Aug. 5, 2011. Once in orbit around Jupiter, the spacecraft will circle the planet 33 times, from pole to pole, and use its collection of eight science instruments to probe beneath the gas giant's obscuring cloud cover. Juno's science team will learn about Jupiter's origins, structure, atmosphere and magnetosphere, and look for a potential solid planetary core. 
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Juno's name comes from Greek and Roman mythology. The god Jupiter drew a veil of clouds around himself to hide his mischief, and his wife, the goddess Juno, was able to peer through the clouds and reveal Jupiter's true nature. 
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NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of the California Institute of Technology in Pasadena. 
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Quelle: NASA

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Update: 25.07.2014 

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Juno-Sonde auf JUpiter-Kurs

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Rückblick: JUNO-Sonde Erde-Blick bei FlyBy

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Quelle: NASA

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Update: 15.12.2014 

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NASA's Juno Gives Starship-Like View of Earth Flyby

This cosmic pirouette of Earth and our moon was captured by the Juno spacecraft as it flew by Earth on Oct. 9, 2013.

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When NASA’s Juno spacecraft flew past Earth on Oct. 9, 2013, it received a boost in speed of more than 8,800 mph (about 3.9 kilometers per second), which set it on course for a July 4, 2016, rendezvous with Jupiter, the largest planet in our solar system. One of Juno's sensors, a special kind of camera optimized to track faint stars, also had a unique view of the Earth-moon system. The result was an intriguing, low-resolution glimpse of what our world would look like to a visitor from afar.
"If Captain Kirk of the USS Enterprise said, ‘Take us home, Scotty,’ this is what the crew would see," said Scott Bolton, Juno principal investigator at the Southwest Research Institute, San Antonio. “In the movie, you ride aboard Juno as it approaches Earth and then soars off into the blackness of space. No previous view of our world has ever captured the heavenly waltz of Earth and moon."
The Juno Earth flyby movie is available at: http://www.youtube.com/watch?v=_CzBlSXgzqI&feature=youtu.be . The music accompaniment is an original score by Vangelis.
The cameras that took the images for the movie are located near the pointed tip of one of the spacecraft's three solar-array arms. They are part of Juno's Magnetic Field Investigation (MAG) and are normally used to determine the orientation of the magnetic sensors. These cameras look away from the sunlit side of the solar array, so as the spacecraft approached, the system's four cameras pointed toward Earth. Earth and the moon came into view when Juno was about 600,000 miles (966,000 kilometers) away -- about three times the Earth-moon separation.
During the flyby, timing was everything. Juno was traveling about twice as fast as a typical satellite, and the spacecraft itself was spinning at 2 rpm. To assemble a movie that wouldn't make viewers dizzy, the star tracker had to capture a frame each time the camera was facing Earth at exactly the right instant. The frames were sent to Earth, where they were processed into video format.
"Everything we humans are and everything we do is represented in that view," said the star tracker's designer, John Jørgensen of the Danish Technical University, near Copenhagen.
Also during the flyby, Juno's Waves instrument, which is tasked with measuring radio and plasma waves in Jupiter's magnetosphere, recorded amateur radio signals. This was part of a public outreach effort involving ham radio operators from around the world. They were invited to say "HI" to Juno by coordinating radio transmissions that carried the same Morse-coded message. Operators from every continent, including Antarctica, participated.
"With the Earth flyby completed, Juno is now on course for arrival at Jupiter on July 4, 2016," said Rick Nybakken, Juno project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
The Juno spacecraft was launched from Kennedy Space Center in Florida on August 5, 2011. Juno’s launch vehicle was capable of giving the spacecraft only enough energy to reach the asteroid belt, at which point the sun’s gravity pulled it back toward the inner solar system. Mission planners designed the swing by Earth as a gravity assist to increase the spacecraft’s speed relative to the sun, so that it could reach Jupiter. (The spacecraft’s speed relative to Earth before and after the flyby is unchanged.)
After Juno arrives and enters into orbit around Jupiter in 2016, the spacecraft will circle the planet 33 times, from pole to pole, and use its collection of science instruments to probe beneath the gas giant's obscuring cloud cover. Scientists will learn about Jupiter's origins, internal structure, atmosphere and magnetosphere.
Juno's name comes from Greek and Roman mythology. The god Jupiter drew a veil of clouds around himself to hide his mischief from his wife, but the goddess Juno used her special powers to peer through the clouds and reveal Jupiter's true nature.
NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of the California Institute of Technology in Pasadena.
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Quelle: NASA

 

 

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