ESA - JUICE updates

[Rondaz]

#JUICE, the JUpiter ICy moons Explorer mission has reached its next milestone Raising hands On its Earthly journey via different Airbus sites in Europe, the spacecraft has arrived at Airbus’ satellite integration centre in Friedrichshafen Flag of Germany for final integration.

https://twitter.com/AirbusSpace/status/1253271836898574336

[zubenelgenubi]

Cross-post re: LV:

JUICE will be launched by Ariane 5. Ariane 64 is only a backup.

https://twitter.com/TechSpatiales/status/1262498087534297088

[bolun]

#6: START OF ASSEMBLY AND INTEGRATION FOR JUICE

26 June 2020

Despite certain operational difficulties caused by the COVID-19 pandemic, the assembly and integration of the flight model for ESA's JUpiter ICy moons Explorer (JUICE) spacecraft has continued with few delays during the first six months of the year.

On 2 September 2019, the flight structure – the main skeleton of JUICE - was delivered to the Arianegroup facility in Lampoldshausen, Germany (see JUICE Journal #5).

Over the next seven months, technicians completed the integration of the chemical propulsion system: this included the large propellant tanks, the pressurant tanks, the main engine and the attitude control thrusters, together with all the pressure control and propellant distribution hardware, plus all the required piping and supports for thermal hardware and harness (electrical cables).

In April 2020, after the acceptance testing of the propulsion system was successfully completed, the structure was loaded onto a special road transporter, for overnight delivery to the Airbus satellite integration centre facilities in Friedrichshafen, Germany.

The flight model of the spacecraft has now entered its assembly and integration phase. This involves integration of the harness, internal thermal blankets, and the remaining elements of the structure – large external panels and secondary structure brackets used to support different units.

This will be followed by the integration and testing of platform and internal electronic units of the payload. Next in line will be integration of external units such as antennas, deployable appendages and external payload units. The final stage of the assembly and integration process will be the closure of the structure and completion of its thermal protection hardware.

After this, the deployment of some of the appendages will be tested, and then the spacecraft will be transported to ESA's Space Technology and Research Centre (ESTEC) in the Netherlands at the beginning of 2021, where it will undergo its thermal balance / thermal vacuum test in the Large Space Simulator.

https://sci.esa.int/web/juice/-/-6-start-of-assembly-and-integration-for-juice

[jacqmans]

NASA's Jet Propulsion Laboratory built and shipped the receiver, transmitter and electronics necessary to complete the radar instrument for ESA's (European Space Agency's) Jupiter Icy Moons Explorer (JUICE) mission. Set to launch in 2022, JUICE will explore Jupiter and its three large icy moons. The transmitter works by sending out radio waves, which can penetrate surfaces of icy moons so that scientists "see" underneath. The instrument, called Radar for Icy Moon Exploration, or RIME, is a collaboration by JPL and the Italian Space Agency (ASI) and is one of ten instruments that will fly aboard. This photo, shot at JPL on July 23, 2020, shows the transmitter as it exits a thermal vacuum chamber. The test is one of several designed to ensure the hardware can survive the conditions of space travel. The thermal chamber simulates deep space by creating a vacuum and by varying the temperatures to match those the instrument will experience over the life of the mission.

https://photojournal.jpl.nasa.gov/catalog/PIA24025

[leovinus]

Radar for a Giant Planet’s Moons
https://www.centauri-dreams.org/2020/09/22/radar-for-a-giant-planets-moons/

[jacqmans]

Juice solar panels ready to turn into wings

16/10/2020

All ten solar panels for ESA’s Jupiter Icy Moons Explorer, Juice, have arrived at Airbus Defence and Space in The Netherlands ready to be turned into the spacecraft’s two solar wings. The solar panels are a key element of the mission, providing the necessary power to run the spacecraft and operate the science instruments.

Each panel measures about 2.5 m x 3.5 m, and with five on each side of the spacecraft, total an area of about 85 square metres. They have to be folded up to fit inside the launcher, and after launch, will deploy in a distinctive cross-like formation.

En route to Jupiter, Juice will make several gravity assist flybys at Earth, Venus and Mars before heading to the outer Solar System, meaning that the solar panels have to withstand a large temperature range from +110ºC to -230ºC. At Jupiter, there will be times when the spacecraft is temporarily eclipsed by the giant planet and the moons, depriving it from any sunlight, leading to a rapid cool down of the solar arrays. In addition, the spacecraft will be subjected to a harsh radiation environment. Extensive testing is carried out to ensure the spacecraft and its solar arrays can survive these tough conditions.

The next step for the solar panels is to turn them into wings and to test the deployment mechanisms. Further checks will also be made to verify that the spacecraft and its instruments can receive all of the power generated by the solar array even under the most challenging conditions.

Juice is scheduled to launch in 2022, arriving in the Jovian system in 2029. It will investigate Jupiter and three of its planet-sized moons – Ganymede, Europa and Callisto – which are thought to have oceans of liquid water beneath their icy crusts. This makes them extremely interesting to study to better understand the habitability potential of ocean worlds – in our own Solar System and in exoplanet systems beyond.

[jacqmans]

ALL PANELS DELIVERED FOR JUICE'S SOLAR WINGS

16 October 2020

All ten flight model solar panels for ESA's JUICE spacecraft have been delivered to Airbus Defence and Space Netherlands ready to be integrated into solar wings. The solar panels, with a total area of 85 m², are a key element of the mission, providing the necessary power to run the spacecraft and operate the science instruments.

JUICE's solar panels are carbon fibre reinforced honeycomb panels, each measuring about 2.5m × 3.5m, on which a grid of 2356 solar cells, or the Photo-Voltaic Array (PVA), is mounted. The spacecraft's two solar wings will each comprise five panels in a distinctive cross shape. These will be folded up to fit inside the launcher, so an elaborate deployment mechanism needs to be foreseen.

Airbus Defence and Space Netherlands in Leiden is responsible for the panel manufacturing and the deployment mechanism. The design, manufacturing and mounting of the PVA required specific skills and was done by Leonardo in Nerviano, near Milan, Italy.

https://sci.esa.int/web/juice/-/-7-all-panels-delivered-for-juice-s-solar-wings

[eeergo]

RIME PFM has been delivered:

https://twitter.com/ESA_JUICE/status/1330860897342992384

[Mammutti]

https://twitter.com/ESA_JUICE/status/1361250416374255617

Shaky moments for the 2.5m #JUICE High Gain Antenna, to make sure it will withstand the vibrations during launch into space🚀 ! @Thales_Alenia_S @AirbusSpace

[bolun]

#8: SUCCESSFUL INTEGRATION OF JUICE'S 10.6-METRE-LONG ARM

The development of ESA's JUpiter ICy moons Explorer (JUICE) is continuing apace and has hit milestones in recent months: the spacecraft's 10.6-metre-long boom is now attached, many instruments have been integrated, and the mission's high-gain antenna has arrived and undergone rigorous vibration testing to ensure it can withstand launch into space.

In the coming months the spacecraft will undergo major environmental and performance tests, including thermal vacuum, mechanical and electromagnetic compatibility tests, along with the end-to-end test of the ground segment. Furthermore, JUICE's numerous appendages will be test-deployed before preparing to pack up and ship to the launch site.

Image credit: Airbus, Sener

[jacqmans]

JUICE Jupiter probe’s first taste of space

JUICE, the JUpiter ICy moons Explorer mission led by the European Space Agency (ESA), has left Airbus’ satellite integration centre in Friedrichshafen (Germany) and is now on its way to the Large Space Simulator (LSS) chamber of the European Space Agency (ESA) in Noordwijk (Netherlands) for its first taste of space.

Airbus built satellite to start environmental tests

Friedrichshafen, 27 April 2021 – JUICE, the JUpiter ICy moons Explorer mission led by the European Space Agency (ESA), has left Airbus’ satellite integration centre in Friedrichshafen (Germany) and is now on its way to the Large Space Simulator (LSS) chamber of the European Space Agency (ESA) in Noordwijk (Netherlands) for its first taste of space. Over the next 12 months, starting with 31 days in the vacuum chamber in the LSS, the spacecraft will be exposed to the environmental conditions of space and will have to prove it is ready for its journey via Venus and Mars to Jupiter and its mission in the Jovian system.

Since its arrival 12 months ago at the Airbus site, JUICE has been kitted out with its final components including harness, power electronics, on-board computer, communication systems, navigation sensors, thermal hardware and crucially its scientific instruments. At the ESA test centre at ESTEC in Noordwijk, the spacecraft will undergo a full environmental test campaign including verifying its thermal control system and its electrical elements.

Together with their ESA colleagues, a total of 120 Airbus space engineers and subcontractors will prepare and carry out the tests. In July this year, the spacecraft will head for Airbus in Toulouse for flight configuration assembly, before the final environmental tests including electro-magnetic compatibility (EMC), mechanical, deployment, and propulsion.  It will then be shipped to the launch site in Kourou, French Guiana.

The 6.2 ton JUICE spacecraft will set off in 2022 on its near 600 million-kilometre-long journey to Jupiter. The spacecraft will carry 10 state-of-the-art scientific instruments, including cameras, spectrometers, an ice-penetrating radar, an altimeter, radio-science experiment, and sensors to monitor the magnetic fields and charged particles in the Jovian system. JUICE will complete a unique tour of the Jupiter system that will include in-depth studies of three potentially ocean-bearing moons with liquid water, Ganymede, Europa and Callisto.

JUICE will spend more than three years in the Jupiter system, collecting data to provide answers on the conditions for planet formation and the emergence of life. It will spend nine months orbiting the icy moon Ganymede analysing its nature and evolution, and its potential habitability.

https://www.airbus.com/newsroom/press-releases/en/2021/04/juice-jupiter-probes-first-taste-of-space.html

[jacqmans]

https://twitter.com/ESA_JUICE/status/1387573796299739139?s=20

[jacqmans]

Juice arrives at ESA’s technical heart
06/05/2021

The Jupiter Icy Moons Explorer, Juice, has come ‘home’ to ESA’s technical centre in the Netherlands to undergo an extreme environment test in Europe’s largest thermal vacuum chamber to prepare for its journey to the outer Solar System.

The spacecraft arrived at ESTEC, ESA’s European Space Research and Technology Centre, from Airbus Friedrichshafen in Germany last week. It is now being unpacked and prepared to enter the ‘Large Space Simulator’ later this month. It will spend several weeks being subjected to extreme heating and cooling cycles under vacuum, to confirm the spacecraft is ready for its long journey through the Solar System to Jupiter.

Juice will remain at ESTEC until July, before being transported to Toulouse for its final round of tests. From there it will travel to Europe’s Spaceport in French Guiana, to be launched on an Ariane 5 rocket next year.

Once in the Jovian system the mission will make detailed observations of the giant gas planet and its three large ocean-bearing moons – Ganymede, Callisto and Europa – with a suite of remote sensing, geophysical and in situ instruments. The mission will investigate the emergence of habitable worlds around gas giants and the Jupiter system as an archetype for the numerous giant exoplanets, now known to orbit other stars.

https://www.esa.int/Science_Exploration/Space_Science/Juice_arrives_at_ESA_s_technical_heart

[jacqmans]

[jacqmans]

Jupiter antenna that came in from the cold

An instrument destined for Jupiter orbit is checked after completing eight days of cryogenic radio-frequency testing at ESA’s ESTEC technical centre in the Netherlands.

The Sub-millimetre Wave Instrument of ESA’s Juice mission will survey the churning atmosphere of Jupiter and the scanty atmospheres of its Galilean moons.

Testing took place in ESA’s custom-built Low-temperature Near-field Terahertz chamber, or Lorentz.

The first chamber of its kind, the 2.8-m diameter Lorentz chamber can perform high-frequency radio-frequency testing in realistic space conditions, combining space-quality vacuum with ultra-low temperatures.

“The successful test of the flight hardware inside Lorentz, follows an intensive commissioning phase.” says ESA antenna engineer Paul Moseley. “This demonstration opens up a wide range of testing possibilities for missions to come.”

Meanwhile the flight model of the SWI instrument’s parent Juice spacecraft has itself reached the ESTEC Test Centre, in preparation for a month long thermal vacuum test campaign.

Credits: ESA-G. Porter

[LouScheffer]

Can anyone explain the reason behind the first Earth flyby for Juice?  It's the first flyby after launch, which is puzzling.

With no planetary encounter, or Deep Space Maneuver I could find, JUICE will arrive back at Earth with the same speed it left.  The flyby itself can only change the Earth-relative direction, not velocity.  So why not launch JUICE a year later, with the speed and direction it would have after the Earth encounter?  It should require exactly the same launch performance, and allow another year of development and testing.

The only reasons I can see are somewhat sketchy.  Perhaps it needs to launch during 2022 for some (non-trajectory)  reason (budget, availability of launcher, etc).  Maybe they are worried it will slip, or miss the launch window in some other way, and have already invested a huge amount of effort in tour planning.  This way if it slips, they just launch next year with the trajectory the same from then on.  Maybe they need more time to check out or calibrate the instruments, but this seems unlikely since the trajectory would be 6 years even with the later launch.

[edzieba]

The flyby itself can only change the Earth-relative direction, not velocity.

Gravity assists do not apply just to the outer planets, and do not apply just to increases in velocity. They allow a gain in orbital energy by sapping orbital energy from a larger body.
JUICE does not launch with the post-first-Earth-encounter energy, as then the launch vehicle would need to provide that extra energy.

[plutogno]

JUICE does not launch with the post-first-Earth-encounter energy, as then the launch vehicle would need to provide that extra energy.

The same was done with BepiColombo IIRC. It was launched in a 1-year period solar orbit and then an Earth flyby robbed it of some energy to begin deeper in the solar gravity well

[LouScheffer]

The flyby itself can only change the Earth-relative direction, not velocity.

Gravity assists do not apply just to the outer planets, and do not apply just to increases in velocity. They allow a gain in orbital energy by sapping orbital energy from a larger body.
JUICE does not launch with the post-first-Earth-encounter energy, as then the launch vehicle would need to provide that extra energy.

JUICE does not launch with the post-first-Earth-encounter energy, as then the launch vehicle would need to provide that extra energy.

The same was done with BepiColombo IIRC. It was launched in a 1-year period solar orbit and then an Earth flyby robbed it of some energy to begin deeper in the solar gravity well

I fail to see how this is possible, on very basic physical grounds.  If it does no maneuvers in between, a probe will have exactly the same overall velocity when it returns to the same radius, as gravity is a conservative force.  Furthermore, it crosses the Earth's orbit at exactly the same angle (conservation of orbital angular momentum ensures the tangential component is equal.  Then if the overall velocity is the same, and the tangential component is the same, the angle is the same.)  Thus the probe arrives with exactly the same Earth relative velocity with which it left.  And the whole paradigm of a flyby is that the Earth-relative exit velocity is exactly the same as the Earth-relative entrance velocity.  So the exit Earth-relative speed is exactly what it was at launch.   Therefore you could get exactly the same result by launching in a different direction in the first place.

This calculation is explicit for the a proposed Triton mission that also starts with an Earth flyby:  "A backup launch period is available with the same C3 one year later with one fewer Earth gravity assists, providing a post-Venus trajectory and delivery conditions identical to the nominal launch date."  According to BlackStar, this is likely because the call for proposals specified it must launch in a certain year.

Both Juno and BepiColumbo could benefit from Earth as the first flyby since they maneuvered before they returned to Earth.  Juno did a Deep Space Maneuver of 730 m/s, and BepiColumbo had months of solar-electric propulsion.  In these cases an Earth flyby certainly helps, as it can magnify the on-orbit manuevers.  But if there is no such maneuver, there is no gain.

[CassiniWeenie]

Increase in velocity during a gravity assist is proportional to the distance and angle of the probes flyby of the body. Regardless of whether or not there is a 'maneuver,' Juice will leave the Earth slingshot at a higher velocity.