12/04/2024
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One yr because the launch of ESA’s Jupiter Icy Moons Explorer (Juice), we meet up with core crew members Claire Vallat, Giuseppe Sarri, Olivier Witasse and Ignacio Tanco.
From recollections of launch day to hopes for the longer term, they discuss truthfully in regards to the ups and downs of flying an area mission, and reveal how they’re guaranteeing that Juice will likely be an enormous success.
3… 2… 1… liftoff!
What involves thoughts when the crew casts their minds again one yr?
Claire: “I used to be extraordinarily fortunate that I acquired the possibility to be in Kourou. It was my first ever launch. And what a launch! Simply to see and to listen to and to be so near the launchpad. There was lots of gentle after which lots of noise. It was an extremely intense expertise.”
Claire, who works on planning the operations of Juice’s ten science devices, has labored on Juice since 2015.
“If you work for thus lengthy on a mission that’s nonetheless a bit summary, you’re by no means 100% certain that it’ll really be launched – even when, in fact, you might be assured that it will likely be!
“However simply seeing that rocket within the sky, and realizing that’s your spacecraft inside, that’s when the massive journey really begins.”
For Giuseppe, who led the Juice challenge between 2014 and 2023, the discuss of launch brings again extra anxious recollections.
Giuseppe: “When you have got a launch window, it’s important to launch throughout this window. You can’t merely add one month. Our window began on 5 April and was closing in direction of the top of April.
“The ultimate testing and preparations have been going nicely till a propulsion system take a look at threw up a nasty downside. We have been testing a failure case which implies we simulate a failure in a couple of of the thrusters, after which the system has to reconfigure. Nevertheless it was reconfiguring with much less thrust than we’d have favored.
“We couldn’t afford to launch with the chance that in case we now have a failure, we’d lose the spacecraft. So the Airbus crew needed to work across the clock to make a change to the software program to make the system secure once more.”
Airbus led on constructing the Juice spacecraft. It’s clear that our ESA crew are in awe of what they’ve achieved.
Giuseppe: “On the day of the launch, the whole lot was good with the spacecraft, good with the launcher. However the climate was not cooperating. We got here very, very near launch, however then we needed to cease. And that was a bit of bit demotivating.”
Thankfully, the subsequent day, the lightning strikes stayed away and Juice was cleared for launch. Again in Europe, Olivier took a second to breathe after a traumatic few weeks.
Olivier: “I feel that was probably the most intense interval of my profession: these few weeks across the launch after which the launch itself. Then 10 seconds earlier than launch, because the countdown started, I stated to myself, ‘proper, so now there’s nothing extra we will do, it’s going…’.”
In the meantime, within the mission management room, Ignacio led a targeted crew of front-row mission controllers.
“Till acquisition of sign the whole lot is at all times so tense, as a result of no matter occurs is totally out of your management. You’ll be able to’t see the spacecraft, you’ll be able to’t converse to the spacecraft, and no matter occurs, you’ll be able to’t act on it.
“So that you’re simply sitting there ready and ready, together with your arms tied. Then while you lastly get telemetry you breathe a sigh of aid as a result of you realize the spacecraft is alive. After which while you ship up a command and set up contact with the spacecraft you once more breathe a sigh of aid as a result of your coaching kicks in and no matter occurs, you might be assured that the crew can take care of it.
“From that second, you’re extraordinarily busy. It’s one process after one other. You simply preserve shifting. For Juice, after 23 hours, we have been carried out. I feel it was the quickest launch and early operations section we now have ever accomplished. Then we moved upstairs to the devoted planetary management room to start out with commissioning the spacecraft and devices. And that’s the place the true issues started.”
The RIME antenna – a thorn in our aspect
The antenna carrying Juice’s Radar for Icy Moon Exploration (RIME) instrument was caught. After being folded up for launch, it refused to open up in area. The science that Juice would be capable of obtain at Jupiter was compromised.
Giuseppe: “The expectation for a mission like Juice, which is a cornerstone of science, is totally big. There are excessive expectations from ESA Member States, from the folks placing the cash on the desk. If the mission doesn’t work, it’s a failure of the European House Company.
“However most of all there are tons of of people that have made their scientific profession primarily based on this mission. They might all have their profession ruined. And I actually felt that strain at that second.”
The crew are unanimous of their conviction that the RIME antenna was what wracked their nerves probably the most over the previous yr. Ignacio tells us extra in regards to the problem.
Ignacio: “The antenna is made out of versatile materials. After we hit launch, we anticipated it to flip itself open like a kind of folding tenting tents. We have been involved that if it was saved saved for too lengthy, it might lose its properties, so we wished to deploy it as shortly as potential.
However upon launch, the antenna didn’t absolutely deploy. This state of affairs was not one which Ignacio and his crew had educated for.
Ignacio: “Nobody had considered this, so we needed to proceed very rigorously. Just about each week we needed to throw our newest plan out the window and begin from scratch. This antenna was a thorn in our aspect, constantly current day and evening, blocking the whole lot.
“It took a couple of month of steady work, and the strain was fully completely different from in the course of the launch and early operations section. However luckily, we have been supported by very competent {and professional} people from trade, from the Juice challenge crew, and inside our operations crew, and finally we have been profitable.
“We uncorked a celebratory bottle proper then as a result of all people had simply had sufficient of this caught antenna! It wasn’t my victory, it wasn’t an ESA flight management crew victory, it wasn’t even an ESA victory. It was a European victory.”
Claire had been intently following the progress of releasing the RIME antenna.
Claire: “This was an especially tense interval for the challenge and trade groups. Loads of ups and downs. It’s one thing I’ll preserve in my head for a while.
“Due to this problem, we misplaced a couple of month of commissioning time, and we needed to make up for this misplaced time. Thankfully, the remainder of the instrument commissioning went easily and the evaluation on the finish was very constructive. Some devices are working even higher than we anticipated.”
An ideal launch = additional science at Jupiter
Juice will spend simply 4 years exploring Jupiter and its icy moons, so there is not going to be a lot time after arrival to evaluation scientific observations and repeat measurements. To make sure that the mission is able to do nice science as quickly because it arrives, Olivier and Claire are already engaged on a plan. Along with the groups main every science instrument, they’ve needed to take a couple of massive choices over the previous yr.
Olivier: “Our first choice was straightforward. The launch was good, and we launched on the proper second throughout the launch window. This meant that sure manoeuvres weren’t wanted so we have been left with extra propellant than anticipated. This additional propellant will likely be used to reintroduce a section of the mission that was scrapped a couple of years in the past due to restricted mass funds.
Claire: “We’ll go down to only 200 km above Ganymede’s floor. This may present a lot better knowledge in a number of facets, particularly for the whole lot associated to the geophysical investigation of Ganymede. Being so shut, we could have higher knowledge to characterise the inside of the moon and its plasma atmosphere.
“That is nice, nice information for the science crew as a result of they needed to descope this a part of the mission a couple of years in the past. Nevertheless it had at all times been of their minds that it must be recovered, if in any respect potential.”
Juice’s first well being test
Juice’s devices should be saved in prime situation for arrival at Jupiter. In January, they underwent their first well being test.
Claire: “Roughly twice a yr the mission operators swap on the devices and we do some checks. These could be easy, for instance, practical checks of the well being of every instrument. They may also be a bit extra complicated, like interference checks between completely different devices.
“This one was, in fact, our first time. And also you by no means know if issues can go unsuitable or should you made any errors whereas growing the plan.”
Fortunately all ten devices handed their well being checks with flying colors. However 4 needed to endure deliberate surgical procedure.
Ignacio: “We knew already at launch that the onboard software program on a number of of the devices was only a placeholder, that wanted updating to function efficiently at Jupiter. Updating software program is a fragile operation as a result of it’s essential mainly patch your complete reminiscence. Then it’s essential reboot. However in the long run the whole lot ran and not using a hitch.”
The dreaded spacecraft mind improve
The spacecraft itself additionally required a software program replace. The method is a bit like updating your telephone or laptop’s working system, however rather more sophisticated and far, rather more traumatic.
Giuseppe: “Although the spacecraft was secure at launch, the onboard software program didn’t have all of the capabilities essential to function the spacecraft at Jupiter. So we agreed with Airbus that we’d patch this in flight in 2024 to provide them extra time to complete the event.
“There was a second the place we needed to load the software program and put in reminiscence. Then there was one other second the place we needed to swap off the outdated software program and swap on the brand new one. On this transition, the spacecraft had to enter a secure mode, the place it needed to do by the whole lot by itself.”
Ignacio (with emphasis): “We hate doing this as a result of switching off the spacecraft implies that for some minutes you really don’t see it.
“We had 20 minutes the place we have been satisfied that we must be listening to from Juice however we weren’t.
“It ought to have come again.
“It must be there.
“Come on.
“What’s happening?
“At that second you begin having all these completely different situations going via your head. You understand you can’t act, or reasonably you shouldn’t act. As a result of should you begin appearing blindly, the possibility that you simply make an issue worse is excessive, so it takes self-discipline to attend, to not take motion.
It sounds enormously traumatic. How does Ignacio keep calm in these conditions?
Ignacio: “I meditate.” [he says simply, shrugging]
“I sit down and breathe for 35 minutes a day, and this helps me so much. I fairly often suppose it’s most likely the one instrument that makes the largest distinction in how I method work and the way I take care of the sudden traumatic conditions.
“However I have to say it is a massive a part of the mental satisfaction of spacecraft operations, really coping with this stuff and overcoming them.
“Anyway, after a brief delay, we acquired telemetry from the spacecraft. We’ve got the brand new software program energetic on board and it is working very nicely. We managed to resolve lots of the present issues – small bugs that we had recognized that have been all corrected by Airbus. We now have a a lot cleaner spacecraft to run.”
The double flyby – a balancing act in additional methods than one
Claire: “We’ve lately entered what I might say is our first battle negotiation and determination with the completely different instrument groups. The flyby of the Moon and Earth in August is the one alternative we’ll have for sure measurements in the course of the cruise section. Understandably, all people’s interested by getting science out of it.”
Later this yr Juice will fly by first the Moon then Earth in fast succession, on a world-first try to make use of the gravity of each as springboard in direction of Jupiter. This lunar-Earth gravity help can be one thing of a bonus for instrument calibration and science, potential solely as a result of Juice launched throughout a really particular time window.
Olivier and Claire lately had the difficult process of determining which devices to function at what moments in the course of the distinctive lunar flyby. The method has led to debate between instrument groups.
Olivier: “Our highest precedence in the course of the cruise section is to make sure that we’re able to do most science at Jupiter. Sadly, we now have one other problem with the RIME instrument: it’s choosing up some disturbances throughout the spacecraft. The Moon flyby is the one probability we now have earlier than we arrive at Jupiter to check how this background interference is degrading the efficiency of RIME. The crew can test this facet by analysing echoes from a floor, and growing an algorithm to appropriate the issue.”
To this point, so simple, however making time for RIME means much less observing time for the opposite devices. Following weeks of full of life dialogue, the ultimate choice was made: RIME could have a while to look at alone in the course of the closest method to the Moon, throughout which period all different devices will likely be switched off or in quiet mode.
Olivier: “Having to face these negotiations now’s actually precious as a result of it helps develop the dialogue processes and the belief in one another. It’s so necessary to construct belief so that folks know that we act pretty, that we hear and that we attempt to strike a compromise.”
Claire: “The massive distinction is that right here we’re in spring and we’re planning for a flyby occurring in August. In the course of the Jupiter tour we could have occasion after occasion after occasion – generally a number of Galilean moon flybys and shut approaches to Jupiter per 30 days. We have to pre-empt a few of the conflicting wants of the instrument groups to make sure that we will address the extreme operations in the course of the nominal mission.”
Working collectively for a profitable mission
Claire: “Juice is enormously complicated not solely from an engineering or scientific standpoint, but additionally from a human standpoint. We’ve got so many groups unfold all over the world, with alternative ways of working and generally barely completely different pursuits. A giant a part of our jobs is to make sure that all these persons are conscious of the completely different scientific, technological and operational constraints in order that we’re all working for the most effective of the mission.
“That is extraordinarily complicated however extraordinarily rewarding. You may have the sensation you’re reaching one thing massive, you realize? You are only a small piece of it, however the full puzzle is simply wonderful.”
Giuseppe: “From the very starting we aimed to have sincere and clear communication between the completely different groups. I by no means pointed the finger. My crew by no means level the finger. And as a reward, the instrument groups, each time there was an issue, have by no means pointed the finger at ESA.
“I’m very happy with how all of us labored collectively and what we’ve managed to realize.”
Olivier: “In November we launched the complete two-hour making of Juice documentary, which I feel provides a very good behind-the-scenes perception into how a challenge crew works along with trade and scientists, into how we construct a spacecraft.”
Ignacio: “I see myself, as they are saying, standing on the shoulders of giants. The complete crew right here at mission management has been working constantly at a really excessive stage during the last yr.”
Juice continues to be Juice, and the strain continues to be excessive
So now that Juice is in area, do the crew see it in a distinct gentle?
Olivier: “Oh no. No, no, no, no, no.
“Juice is Juice! It’s an awesome mission, a totally fascinating mission. It’s simply that the section has modified, so now we now have an actual spacecraft in area to function. For me it’s a transition and I attempt to navigate the most effective for this. I do know there are lots of challenges, in order that’s why I’m nonetheless targeted, targeting my process, and ensuring that we don’t waste any time.
“As a result of each single factor that we do now’s to verify we’re prepared in seven years after we arrive at Jupiter. We are able to’t afford to hibernate our minds.”
Giuseppe: “With area exploration, you actually have the sensation that you’re strolling on the sting of a mountain. A step to the left is a full glory. A step to the correct is full catastrophe. The distinction between full glory and full catastrophe will not be that massive. You do not at all times know the way it will go. And that’s actually what makes issues fascinating, thrilling and satisfying.”
Should you loved this text, meet extra scientists and engineers who’ve labored on Juice in our feature-length documentary, The making of Juice.
