DLR - Blogs

German Space Operations Center commands small satellite with next-generation software via Cubesat Space Protocol

Fri, 15 Mar 2024 13:03:36 +0100

Achtung:

01000001 01100011 01101000 01110100 01110101 01101110 01100111

Error 404: Was bedeutet diese Fehlermeldung?

Es kann verschiedene Gründe haben, weshalb ein Inhalt nicht gefunden wird:

Der Inhalt wurde umgezogen oder gelöscht (letzteres kommt nur sehr selten vor).
Die eingegebene Adresse oder der Link, der Sie hierhin geführt hat, ist fehlerhaft (z.B. Tippfehler).

Wir empfehlen, die Suchfunktion auf unserem Webportal DLR.de zu verwenden.

Durchsuchen Sie den Web-Auftritt DLR.de

Generated by Readability.php.

German instrument to study Moon's eternal shadows with private mission

Wed, 28 Feb 2024 13:30:00 +0100

Stromausfall!

Die von Ihnen gewählte URL ist leider nicht vorhanden.

Error 404: Was bedeutet diese Fehlermeldung?

Es kann verschiedene Gründe haben, weshalb ein Inhalt nicht gefunden wird:

Der Inhalt wurde umgezogen oder gelöscht (letzteres kommt nur sehr selten vor).
Die eingegebene Adresse oder der Link, der Sie hierhin geführt hat, ist fehlerhaft (z.B. Tippfehler).

Wir empfehlen, die Suchfunktion auf unserem Webportal DLR.de zu verwenden.

Durchsuchen Sie den Web-Auftritt DLR.de

Generated by Readability.php.

Serendipitous science from asteroid Apophis' Earth near miss

Thu, 22 Feb 2024 08:50:00 +0100

Achtung:

01000001 01100011 01101000 01110100 01110101 01101110 01100111

Error 404: Was bedeutet diese Fehlermeldung?

Es kann verschiedene Gründe haben, weshalb ein Inhalt nicht gefunden wird:

Der Inhalt wurde umgezogen oder gelöscht (letzteres kommt nur sehr selten vor).
Die eingegebene Adresse oder der Link, der Sie hierhin geführt hat, ist fehlerhaft (z.B. Tippfehler).

Wir empfehlen, die Suchfunktion auf unserem Webportal DLR.de zu verwenden.

Durchsuchen Sie den Web-Auftritt DLR.de

Generated by Readability.php.

Second TRIPLE-IceCraft expedition to the Antarctic: Between battling a snowstorm and loading a dishwasher – Part 2

Tue, 23 Jan 2024 09:30:00 +0100

Achtung:

Reisende mit dem Ziel ‚DLR‘ werden auf andere Seiteninhalte weitergeleitet.

Error 404: Was bedeutet diese Fehlermeldung?

Es kann verschiedene Gründe haben, weshalb ein Inhalt nicht gefunden wird:

Der Inhalt wurde umgezogen oder gelöscht (letzteres kommt nur sehr selten vor).
Die eingegebene Adresse oder der Link, der Sie hierhin geführt hat, ist fehlerhaft (z.B. Tippfehler).

Wir empfehlen, die Suchfunktion auf unserem Webportal DLR.de zu verwenden.

Durchsuchen Sie den Web-Auftritt DLR.de

Generated by Readability.php.

Second TRIPLE-IceCraft expedition to Antarctica: Return to the eternal ice – Part 1

Mon, 11 Dec 2023 12:30:00 +0100

Bitte wenden:

Hier geht es leider nicht weiter ...

Error 404: Was bedeutet diese Fehlermeldung?

Es kann verschiedene Gründe haben, weshalb ein Inhalt nicht gefunden wird:

Der Inhalt wurde umgezogen oder gelöscht (letzteres kommt nur sehr selten vor).
Die eingegebene Adresse oder der Link, der Sie hierhin geführt hat, ist fehlerhaft (z.B. Tippfehler).

Wir empfehlen, die Suchfunktion auf unserem Webportal DLR.de zu verwenden.

Durchsuchen Sie den Web-Auftritt DLR.de

Generated by Readability.php.

On Earth instead of in space – satellite software tested using a particle accelerator

Fri, 03 Nov 2023 08:20:00 +0100

Achtung:

Hier geht es mit Sicherheit nicht weiter

Error 404: Was bedeutet diese Fehlermeldung?

Es kann verschiedene Gründe haben, weshalb ein Inhalt nicht gefunden wird:

Der Inhalt wurde umgezogen oder gelöscht (letzteres kommt nur sehr selten vor).
Die eingegebene Adresse oder der Link, der Sie hierhin geführt hat, ist fehlerhaft (z.B. Tippfehler).

Wir empfehlen, die Suchfunktion auf unserem Webportal DLR.de zu verwenden.

Durchsuchen Sie den Web-Auftritt DLR.de

Generated by Readability.php.

What is new about the German radar satellites?

Thu, 02 Nov 2023 16:10:00 +0100

Bitte wenden:

Hier geht es leider nicht weiter ...

Error 404: Was bedeutet diese Fehlermeldung?

Es kann verschiedene Gründe haben, weshalb ein Inhalt nicht gefunden wird:

Der Inhalt wurde umgezogen oder gelöscht (letzteres kommt nur sehr selten vor).
Die eingegebene Adresse oder der Link, der Sie hierhin geführt hat, ist fehlerhaft (z.B. Tippfehler).

Wir empfehlen, die Suchfunktion auf unserem Webportal DLR.de zu verwenden.

Durchsuchen Sie den Web-Auftritt DLR.de

Generated by Readability.php.

New, first destination for the Lucy spacecraft – a visit to Dinkinesh, 'you are marvellous'

Mon, 30 Oct 2023 09:00:00 +0100

Achtung:

01000001 01100011 01101000 01110100 01110101 01101110 01100111

Error 404: Was bedeutet diese Fehlermeldung?

Es kann verschiedene Gründe haben, weshalb ein Inhalt nicht gefunden wird:

Der Inhalt wurde umgezogen oder gelöscht (letzteres kommt nur sehr selten vor).
Die eingegebene Adresse oder der Link, der Sie hierhin geführt hat, ist fehlerhaft (z.B. Tippfehler).

Wir empfehlen, die Suchfunktion auf unserem Webportal DLR.de zu verwenden.

Durchsuchen Sie den Web-Auftritt DLR.de

Generated by Readability.php.

On Innovative Reference Targets and Analysis-Ready Radar Data

Tue, 24 Oct 2023 09:00:00 +0200

Achtung:

Hier geht es mit Sicherheit nicht weiter

Error 404: Was bedeutet diese Fehlermeldung?

Es kann verschiedene Gründe haben, weshalb ein Inhalt nicht gefunden wird:

Der Inhalt wurde umgezogen oder gelöscht (letzteres kommt nur sehr selten vor).
Die eingegebene Adresse oder der Link, der Sie hierhin geführt hat, ist fehlerhaft (z.B. Tippfehler).

Wir empfehlen, die Suchfunktion auf unserem Webportal DLR.de zu verwenden.

Durchsuchen Sie den Web-Auftritt DLR.de

Generated by Readability.php.

Life on Venus? A DLR FAQ about the trace gas phosphine

Fri, 25 Aug 2023 15:30:45 +0200

Life on Venus? A DLR FAQ about the trace gas phosphine

25 August 2023 | Space

Artist’s impression of Venus, where astronomers may have first detected phosphine in 2020. Data acquired by the James Clerk Maxwell Telescope on Mauna Kea (Hawaii) and the Atacama Large Millimetre/Submillimetre Array (Chile) were analysed for this. Phosphine could be present in the upper layer of the cloud cover. However, the observation is controversial among experts.

Credit:

ESO/M. Kornmesser/L. Calçada & NASA/JPL/Caltech (CC BY 2.0)

In 2020, the planetary research community and the interested public turned their attention to Venus. A research team from the University of Cardiff had detected the gas phosphine in the high clouds of Earth’s inner neighbouring planet for the first time. Phosphine (PH3) is produced on Earth, either naturally by organic weathering processes or artificially – for example for use as fertiliser. So, were traces of life on Earth’s neighbour indirectly discovered in 2020 by detecting phosphine? That would have been a sensation. Or was it much ado about nothing?

After an extensive response in the media and on the internet, the first disillusionment came rather quickly. Criticism and even opposition soon arose. The evidence was not statistically significant, some said; even the presence of phosphine did not necessarily mean that it was of biological origin, others emphasised. Subsequently, additional observations and measurements using telescopes were carried out. It must be emphasised that even the authors of the Cardiff study never claimed to have found traces of life in Venus’ atmosphere. Further studies were mostly unable to detect phosphine in the venusian atmosphere. Then, in the summer of 2023, the team from Cardiff that made the first announcement published an additional statement. They had been able to detect phosphine again using the James Clark Maxwell Telescope in Hawaii.

So, what is the current state of affairs? Can we conclude that there is life on Venus or not? And can a team from the DLR Institute of Planetary Research in Berlin shed more light on the darkness? After a lot of discussions in the almost three years since the excitement about the detection of phosphine on Venus, we have compiled a set of Frequently Asked Questions (FAQs).

Why was there so much excitement about phosphine on Venus?

Phosphine can be a biomarker which, as already mentioned, is either of organic origin or artificially produced on Earth. Phosphorus – the element that together with hydrogen makes up phosphine – is essential for life on Earth because all important building blocks of life contain phosphorus. This includes deoxyribonucleic acid (DNA), the carrier of genetic information. Whether phosphine is present in Venus’ atmosphere at all, and if so, in what quantity, is therefore a major topic in planetary research. Proof of the existence of extraterrestrial life would be one of the greatest sensations in the history of scientific research.

Venus is globally and permanently enveloped by clouds of sulphuric acid, which make any view of the hot, solid surface impossible at optical wavelengths. Observations of the molecule phosphine published in 2020 suggest that it might exist at an altitude of between 53 and 61 kilometres. This ultraviolet-light image was acquired in 2016 by the Japanese orbiter Akatsuki.

Credit:

Planet-C Project Team

How did the controversy arise?

The observations and evaluations published since 2020 are very contradictory. On the one hand, very different concentrations of PH₃ were discovered; on the other hand, it was even ruled out that phosphine is a component in the atmosphere of Venus at all. The first published concentration by the Cardiff team in 2020 was 20 ± 10 ppb in the cloud cover of Venus (Greaves et al., 2020) and excited the community. ‘ppb’ stands for ‘parts per billion’, which means that for every molecule of phosphine there are a billion other atmospheric molecules. The evaluation of the same data by another research group could not confirm the value (Snellen et al., 2020). There were further measurements by various groups that shifted the value for the PH₃ concentration downwards.

In 2021, the atmosphere of Venus was also searched for spectral PH₃ signatures by an instrument on board the Stratospheric Observatory for Infrared Astronomy (SOFIA), the joint research aircraft formerly operated by NASA and DLR. The evaluation of these data revealed an upper limit at a likewise very small PH₃ value (Cordiner et al., 2022).

Early, and at that time sensational, images of Venus at close range were transmitted by NASA’s Mariner 10 spacecraft in February 1978 on its way to Mercury. The image data has recently been reprocessed and (right) contrast enhanced. These are false-colour images that can be used to better depict the dynamic processes in Venus’ atmosphere. Clouds of sulphuric acid envelop the planet globally at an altitude of 50 to 60 kilometres. There, the atmospheric pressure is comparable to that on Earth. At this height, the clouds race around the planet at speeds of up to 250 kilometres per hour, 50 times faster than the planet rotates.

Credit:

NASA/JPL-Caltech (Kevin M. Gill)

Why is phosphine not necessarily an indicator of the existence of life??

Detection of PH₃ would not yet be proof of life, because there could also be abiotic – that is, physical rather than biological – processes that produce this trace gas. So, it is important to find out whether the amount of phosphine that might have been detected is really an indication of life. To do this, one has to understand the abiotic processes. Only if all abiotic sources of PH₃ can be excluded, or if they are too weak to be able to produce the measured amount of phosphine on Venus, could it have been produced by organisms.

The processes that could have produced PH₃ abiotically – that is, without life – on Venus were recently presented by Fabian Wunderlich and a team from the DLR Institute of Planetary Research in a paper in Astronomy & Astrophysics. To do this, they determined the abiotic reaction chains that give rise to phosphine in the form of model calculations.

It is only possible to observe the geological structures on the surface of Venus with radar – optical cameras cannot see through the cloud cover. In the 1990s, NASA’s Magellan spacecraft revealed a Venusian surface almost entirely formed by volcanic processes, which raised many scientific questions.

Credit:

NASA/JPL

What do the DLR model calculations suggest and what are the implications?

Fabian Wunderlich, John Lee Grenfell and Heike Rauer from the DLR Institute of Planetary Research, who were responsible for the study, used more details and more recent data in a photochemical 1D model (Wunderlich et al., 2023). Among other things, they have extended the existing model by 79 reactions for a total of 13 species that contain phosphorus. Their work shows that yes, a small amount of PH₃ could be produced at altitudes between 50 and 60 kilometres (in the cloud cover of Venus) by purely abiotic reactions.

However, the error margins in the model calculations are very large. The amount of phosphine could differ – depending on the scenario – by six orders of magnitude – that is, by a factor of one million. So, improved knowledge about the atmospheric processes that involve phosphorus is needed. More precise observations of life forms on Earth that produce phosphorus compounds or in which phosphorus-related processes take place are also required. To answer the question as to whether PH3 is a biosignature, the detection of other phosphorus compounds such as phosphorus monoxide would be helpful. This is formed abiotically in the lower atmosphere of Venus – probably through the decay of larger observed molecules containing phosphorus – and is then transported to the upper layers.

For future observation and modelling of the Venusian atmosphere, the DLR work provides important information and poses critical questions – both for observational and modelling research and for the community that determines reaction rates in the laboratory.

After more than two decades of evaluating the measurements performed by NASA’s Magellan mission during the 1990s, a great many questions have arisen about the formation and geological development of Venus. They are to be answered with new space missions. Why, for example, did Venus – which is almost the same size as Earth, with almost the same mass and a very similar geochemical ‘inventory’ – develop so differently? And was there once water, perhaps even life, on Venus too? ESA’s EnVision mission will address these questions in the next decade. DLR is developing part of the spectrometer for this mission.

Credit:

ESA/VR2Planets/Damia Bouic

Which space missions could provide clarification?

ESA’s Jupiter Icy Moons Explorer (JUICE) mission, in which DLR is involved, will visit Venus on its way to the Jupiter system. A close fly-by to accelerate and modify its elliptical trajectory is planned for August 2025. The JUICE Submillimetre Wave Instrument (SWI), which was developed and built under the leadership of the Max Planck Institute for Solar System Research, will be able to detect very low phosphine concentrations.

The JUICE spacecraft at Jupiter and its moons

Credit:

ESA/ATG medialab (spacecraft); NASA/JPL/DLR (Jupiter, moons)

Off-topic for all space and Jupiter enthusiasts

DLR’s contributions to the JUICE mission will be deployed after the spacecraft’s arrival in the Jupiter system. Our planetary research is involved in the mission with the GALA instrument and the JANUS camera, as well as through other scientific team memberships, some of which are funded by the German Space Agency at DLR.

You can read more about the JUICE mission here on the blog under the tag ‘JUICE \ GALA’ and on our mission page on DLR.de.

Generated by Readability.php.

High-tech drones and cardboard boxes for the future of humanitarian aid

Sun, 04 Jun 2023 08:00:00 +0200

High-tech drones and cardboard boxes for the future of humanitarian aid

4 June 2023 | Aeronautics

Wings for Aid and DLR make final flight preparations

Credit:

Hello, dear technology enthusiasts! I must tell you about a recent experience that had us on the edge of our seats. The days were full of tension, little sleep, adrenaline and plenty of pride. The protagonists of this story? Our Dutch friends from Wings for Aid and Sven Lorenz and Martin Laubner from the DLR Institute of Flight Systems. Together, we conquered the skies in a way that would have sounded like science fiction just a few years ago.

A first-hand report on flight tests in South Africa

Wings for Aid MiniFreighter on the 'runway'

Credit:

After a 20-hour journey, we finally arrived at the test site near the southernmost tip of South Africa. There stood the unmanned 'MiniFreighter' aircraft from Wings for Aid. However, 'test site' may be a bit of an exaggeration. The simple farm featured a take-off and landing strip made of earth, mud and stones, lined with bushes – and cattle. There are barely any structures and buildings, and the only infrastructure and equipment around was that which Wings for Aid brought with them – and one old, corrugated iron shed that doubtless had plenty of stories to tell. We brought a tent to protect us from the sun and rain. Inside, we set up our control centre, consisting of a ground control station, several laptops, a weather station and equipment providing the data links to the drone.

What may seem like adverse circumstances at first glance were, in fact, ideal conditions for an automated flight beyond visual line of sight. After weeks at sea in a transport container, the unmanned aircraft arrived, ready to be put into operation for the first time in South Africa. After the necessary inspections, preflight tests, briefings and a strong cup of coffee, we began preparing for the first flight – an exciting moment!

An exciting moment – the new unmanned aircraft takes off for its first flight beyond visual line of sight

Credit:

With a take-off mass of over 600 kilograms, this drone represents a new, larger generation of transport systems. And there is something unique about this one: it is specifically designed to deliver supplies to people in hard-to-reach areas. Specialised cardboard boxes have been developed for this purpose, which can hold more than 20 kilograms of payload and are equipped with aerodynamic brake flaps and a crumple zone. One of these 'MiniFreighter' aircraft can carry and drop a total of eight of these boxes. Several drones working together will to be able to autonomously transport a large amount of supplies in the future.

We wish you could have seen the Wings for Aid aircraft handling the unmade and unpaved runways: not just once, but over and over again! During hour-long flights, the drone proved its endurance, reliably dropped its cargo and even mastered the initial challenges associated with operating beyond visual line of sight – an important step towards future autonomous air freight transport.

The flight test team loads the unmanned aircraft for its first mission in South Africa

Credit:

A technology with the potential to become a real game-changer, especially in times of climate change

We also expect the frequency of natural disasters and severe weather events to increase, so we need to develop efficient and rapidly deployable solutions to support the people affected. This technology can supply remote places and even individual families with significant amounts of vital aid, even when traditional transport routes are impassable.

"These drones, which would only fly over sparsely populated areas and below regular air traffic, could represent an innovative and cost-effective transport solution," explains Sven Lorenz, who leads the DLR project 'Automated Low Altitude Air Delivery – Cross Country' (ALAADy-CC). The flight tests with Wings for Aid are just one part of a series of exciting research activities at the DLR Institute of Flight Systems that make up this project.

The control centre at dusk

Credit:

We deal with, among other things, methods and technologies for flight testing innovative larger drone configurations that cannot be found on the current market. We are faced with the question of how to certify and safely operate these unmanned aircraft systems in the future without driving up development costs. Safety, as in all areas of aviation, is our top priority. However, at the same time, drones must be more cost-efficient than manned aircraft.

Fortunately, new methods for assurance and certification are being developed at the Institute. Unmanned aircraft systems of course have the significant advantage that no humans are on board. It is therefore much easier to allow drones fly in places where there is little other air traffic and very few people, as was the case for our flight campaign in South Africa.

As it still requires many personnel to operate these drones today, we are researching technologies to increase the level of autonomy of these systems. Drones should seamlessly integrate into the logistics of humanitarian aid, with as little human interaction as possible.

Would you like to learn more? Take a look at our project Drones4Good. In this project, the Department of Unmanned Aircraft in Braunschweig is researching how to equip a drone with safety-critical artificial intelligence that will enable it to drop humanitarian goods automatically in the future. Today, a human operator is still needed, who is located either on site or who at least receives real-time video from the delivery target location.

Generated by Readability.php.

JUICE launch to Jupiter: GALA diary from Kourou

Wed, 12 Apr 2023 12:00:00 +0200

DLR - Blogs - All blog posts

By DLR Blogs

Credit: ESA/ATG medialab (probe); NASA/JPL/DLR (Jupiter, moons)

Animation of the JUICE spacecraft flyby of Jupiter and its moons

Part 1 – Wednesday, 12 April 2023, 07:00 in Kourou, 12:00 in Berlin

The day before the big day: Tomorrow, the JUICE mission will launch towards Jupiter, and the DLR team will be there in Kourou! After a smooth journey via Paris, we arrived at the European spaceport in French Guiana last night. Now we are looking forward to the launch of the Ariane 5 rocket tomorrow morning at 09:15 local time (14:15 CEST). Our instruments GALA and JANUS will be sent to the Jupiter system on the JUICE spacecraft. geschickt.

We are a small group of engineers and researchers from the DLR Institute of Planetary Research in Berlin who, together with other colleagues, have worked hard over the last few years to develop GALA from an idea into a space-qualified instrument.##markend##

Already at the airport we met many familiar faces behind the other JUICE instruments. Our Japanese GALA colleagues from the Japanese space agency, JAXA, were also there. Whereas in previous years we often met with serious faces to discuss problems that had arisen, the mood is now relaxed and full of anticipation. Everyone is as excited as little children before Christmas!

What will our day be like tomorrow? We’ll be up early and put on the appropriate work clothes...:

Our work clothes for the launch. We want to look smart!

At around 06:30, we will set off in the direction of the Toucan and Carapa observation platforms. These are located on small mountains five and thirteen kilometres away from the launchpad respectively. This will put us at the launch site, but at a safe distance from which we will see the rocket rise above the jungle with a bright glow as it quickly gains altitude. The deep rumble of the rocket's engines will be heard by the onlookers after a delay of a few seconds.

If the clouds are not too thick, we will see the rocket rise further and further. After 2:16 minutes, the solid boosters will separate, followed by the separation of the upper stage from the main stage after 8:44 minutes. Almost 28 minutes after launch, and at an altitude of approximately 2000 kilometres, the JUICE spacecraft will finally separate from the upper stage. From then on, it will fly freely. The most important moments after that come another five minutes later, when the spacecraft makes its first independent radio contact with Earth, and the deployment of the huge solar panels, 17 minutes later.

Ariane 5 shortly before leaving the Final Assembly Building at the Spaceport in Kourou, French Guiana

If all this is successful, we have a mission – and can toast with a Ti' Punch or two, a local speciality ;-)

More about the launch of the Jupiter mission JUICE

You can follow the launch live on ESA WEB TV or on ESA's Livestram on YouTube. The launch is scheduled for 14:15 CEST – it’s best to tune in a little earlier! You can find more news and information on ESA´s JUICE mission Twitter channel, DLR's main channell and our own channel for the GALA instrument (@GALA_JUICE) – as long as we don't all lose our smartphones in the excitement!

By the way...

Anyone interested in DLR shirts, books and other merchandising will find what they are looking for at the Space Shop of the Social Services at DLR. The proceeds go to charity.

TrackbackURL

About the author

Kay Lingenauber studied aerospace engineering and has worked in the field of hardware development at the DLR Institute of Planetary Research since 2005. He was involved in the design and integration of the BepiColombo Laser Altimeter (BELA). to authorpage

Posts with similar themes

Generated by Readability.php.

TRIPLE-IceCraft Expedition to Antarctica – Drilling through the ice shelf - part 5

Thu, 30 Mar 2023 08:00:00 +0200

DLR - Blogs - All blog posts - TRIPLE-IceCraft Expedition to Antarctica – Drilling through the ice shelf

By DLR Blogs

Credit: DLR/RWTH Aachen/Dirk Heinen

TRIPLE-IceCraft drilling through the ice

All of us on the team have been working towards this moment for the last few years: we will finally be able to operate our TRIPLE-IceCraft probe on the ice shelf and drill a deep hole there! The probe will now have to prove itself, and we are all very excited. After the successful four-metre-deep test drilling at Neumayer Station III a few days ago, we are optimistic and highly motivated. The transport of the melting probe to the drilling site with an 80-metre-thick ice shelf can start: at around 7:00 (local time), a colleague from the technical team prepares the snow crawler. The container containing the TRIPLE-IceCraft is released from the snow drift and driven forward. Meanwhile, we pack up the last things. In addition to our working container, we also have a living container and a transport sledge to be transported to the drilling site.##markend##

It takes the snow crawler almost two hours to drive to the drilling site, which is located about 18 kilometres away. Our team of operators leaves shortly after with snowmobiles and an Arctic Truck to arrive at the drilling site almost at the same time as the snow crawler. Around 10:00 (local time), we are on site. The containers are uncoupled, and ramps are pushed to the sides with the help of the snow crawler. The living container is parked a little away from the drilling site, so we can use it as an additional, large, comfortable living area without generator noise in the middle of the seemingly endless expanse of the ice shelf.

Credit: Simon Zierke

The transport starts: from left to right, the TRIPLE IceCraft container, a living container and a transport sledge for additional equipment are pulled to the drilling site by a snow crawler

We prepare everything and again clear out everything necessary to operate the probe. The generator is started, and TRIPLE-IceCraft is pulled up by the crane. Just one more system check, and then the drilling can finally begin. In the meantime, it is early afternoon.

Credit: DLR/RWTH Aachen/Dirk Heinen

A bird's eye view of our drilling camp

Credit: Jan Audehm

The drilling camp

As expected, the next few hours are a little calmer. We monitor the drilling process of the probe, which is melting in at about three metres per hour, via our control software. This shows us status information and readings from all systems. Photos from the three cameras and measurements from the Forefield Reconnaissance System (FRS) are also displayed live. The images from the cameras are particularly exciting; we keep seeing different layers and structures in the ice channel.

Credit: DLR/RWTH Aachen/Dirk Heinen

Finally, the drilling can start

Credit: DLR/RWTH Aachen/Dirk Heinen

Credit: Jan Audehm

Looking at monitors with status information and measured values, drinking coffee and waiting

At a depth of just over 11 metres, a subsystem suddenly stops sending status information. The power supply module for the systems is responsible for communication between the surface and the melting probe. The system also does not respond to manually sent commands. The communication between the surfaces and the melting probe is working, so we know the supply voltages are still being delivered. Nevertheless, it is not immediately obvious what is causing the error.

We prepare a complete restart of the probe, switch off the heating systems and let the melting probe cool down. Even after the restart, the module does not respond. We have to investigate and repair this on the surface. Therefore, we start the return journey of TRIPLE-IceCraft. After 'only' 11 metres, the disappointment is big but is quickly overcome by the urge to explore, get to the bottom of the cause, and fix the error.

Credit: DLR/RWTH Aachen/Dirk Heinen

View into the melting channel

After just under two hours, TRIPLE-IceCraft has returned to the facility. It is now after midnight, so we stow the essentials and drive the snowmobiles back to Neumayer Station III.

The next day is spent fixing the error and testing the system. To our amazement, the module starts again and communicates as usual. Even in the next few hours and through several restarts, we are unable to reproduce the error pattern. We use the time to further observe the system and improve our Fault Detection, Isolation, and Recovery (FDIR). Even into the evening, no faults occur. We decided to continue the drilling the next day. Unfortunately, we will not have enough time to break through the ice shelf as we had planned. Our return flight is scheduled in a few days, as a bad weather front has been announced. And before the flight, everything must be dismantled, safely stowed away and transported back to the vicinity of the station. We need two days for this. Therefore, we only have one day left for drilling, and we want to use it to drill as deep as possible so that we can gain further experience in operating the TRIPLE-IceCraft and record more measurement data.

Credit: DLR/RWTH Aachen/Dirk Heinen

TRIPLE-IceCraft is put back into the existing hole

We start early in the morning again, drive to the drilling site and use the existing hole for drilling. TRIPLE-IceCraft is set in place and drives into the melt channel at a speed of seven metres per hour. Once at the bottom, the probe sits up, and the winch system brakes automatically. Now we start the melting process again. It's back to waiting and monitoring. TRIPLE-IceCraft melts steadily deeper into the ice, this time without any unexpected events. In the camera images, we can see different layers of ice. From time to time, holes become visible where presumably the meltwater has run off. We take turns to monitor as we plan to drill deep into the night today.

Credit: Jan Audehm

In the headlights of the Arctic Truck, we monitor TRIPLE-IceCraft's return to the melt channel

It is getting darker and also noticeably colder. Around 22:00 (local time), we have to stop drilling and start retrieving the probe. In the meantime, we have melted more than 25 metres deep into the ice shelf. This corresponds to about one-third of the thickness of the ice shelf at the drilling site. The return journey with the rewinding of the cable into the interior of the probe also takes several hours. Shortly before 14:00 (local time), TRIPLE-IceCraft is completely back on the surface. We stow the essentials and arrive back at Neumayer Station III shortly before 16:00.

We will need the next one-and-a-half days to prepare the return transport of the probe and the associated material. The return transport to Germany will only take place when the next cargo ship arrives in December 2023/January 2024. Therefore, our material will remain close to Neumayer Station III during the Antarctic winter. We dismantle the crane and stow the TRIPLE-IceCraft and the rest of the equipment in the container. While waiting to be picked up, we are informed by radio that our return flight will be delayed by a few days. Unfortunately, the extra days are still not enough to unpack everything, continue drilling and pack it up again. Shortly afterwards, the snow crawler also arrives to pick up the two containers and the sledge. The TRIPLE IceCraft container is parked directly where it will stay for the next months in the Antarctic winter. The living container and the sledge will be unloaded near the station.

Credit: DLR/RWTH Aachen/Dirk Heinen

TRIPLE-IceCraft moves backwards out of the hole. The camera module, including the lighting, is still about half a metre deep in the ice. The light produced is white, but mainly the blue component penetrates the ice.

We use the next few days for documentation and to organise the return cargo. During the last nights at Neumayer Station III, we are lucky enough to observe a few more southern polar lights before heading north again.

Credit: Simon Zierke

Polar lights over Neumayer Station III

First, we fly with Polar 5 to the Norwegian Antarctic station Troll. After a short stay with an overnight stay at Troll research station, we fly on to Cape Town. In Cape Town, we have a few hours at the airport before we take a scheduled flight to Amsterdam. A few more hours by car and we have made the return journey of over 50 hours.

Credit: DLR/RWTH Aachen/Dirk Heinen

Departure at Troll

Despite the unexpected challenges, we managed to successfully deploy our TRIPLE-IceCraft melt probe in the harsh conditions of Antarctica! We drilled two boreholes, one of them 25 metres deep. The fault that occurred could not yet be clearly identified, but it could be narrowed down considerably. Through troubleshooting, other possible fault cases could also already be identified. We have adapted our FDIR accordingly to catch these error cases in the future. We learned a lot about the system during the test, recorded a lot of measurement data and are now looking forward to analysing the data.

Back in Aachen, we will continue to run our engineering model of the probe. This will allow us to investigate the identified errors further in order to rule out their recurrence in future missions. We will do our utmost to test TRIPLE-IceCraft in the ice again as soon as possible and deploy it even deeper to eventually reach the ocean beneath the ice shelf.

TrackbackURL

About the author

Dirk Heinen researches melting probes and their navigation systems. Melting probes are used to penetrate and explore glaciers and ice shelves and to reach underlying subglacial lakes. Currently, the melting probes are used in terrestrial analogue missions with the aim of being able to explore subglacial oceans of the icy moons Europa and Enceladus in situ in the future. to authorpage

Generated by Readability.php.

GALA on JUICE Part 3 – The challenge of radiation exposure on the 'Mount Everest of the Solar System'

Mon, 27 Mar 2023 10:10:00 +0200

DLR - Blogs - All blog posts

By DLR Blogs

Credit: JPL/NASA

Artist's impression of Jupiter's magnetic field

The Ganymede Laser Altimeter (GALA) will face one of the most hostile environments in the Solar System while in the Jupiter system. The space around the planet is saturated with an enormously high level of radiation, so strong that it can degrade the performance of orbiting scientific instruments or even destroy them. GALA is one of ten instruments on board the JUICE mission, which will set off for the fifth planet of the Solar System in April 2023. It was meticulously developed and extensively tested to survive and function correctly in this extreme environment.##markend##

Jupiter is the 'Mount Everest of the Solar System' in terms of radiation levels. The Solar System's fifth and most massive planet has the strongest planetary magnetic field. It extends over several million kilometres and captures charged particles such as protons, electrons and ions from the solar wind and the volcanic ejecta of the moon Io. The magnetic field accelerates these particles, turning them into small, charged projectiles that will constantly bombard GALA. Unlike most other planets, Jupiter's 'doughnut-shaped' radiation belt is largely dominated by electrons, which have a higher penetration depth than protons and ions – requiring more shielding material to protect the inner, sensitive parts of the instrument.

In our daily lives, we may see examples of radiation shielding such as the lead coat used in X-ray scans or the thick metal sphere around nuclear reactors. Unfortunately, the interaction of electrons with such shielding produces bremsstrahlung, namely gamma rays, which are high-energy photons with an even greater penetration depth than electrons and can reach even the most well-shielded parts of the instrument. During the closest approach to Jupiter, the radiation flux experienced by GALA will be more than half a million times higher than the average value on Earth – corresponding to more than 7700 mammograms per day.

Part of the GALA transceiver unit. The sensitive detector is in the grey cylindrical part in the middle of the unit, the analogue electronics board (in the image below) is in the pink part of the housing, and the laser optics are in the lower part of the unit (out of focus).

The most radiation-sensitive parts of GALA are the detector and the electronic components in the laser and on the circuit boards. The laser rods are the components in which the laser light is generated, and they are particularly sensitive to radiation, so special laser crystals were developed and qualified for GALA. They are called neodymium-doped yttrium aluminium garnet (Nd:YAG) crystals and are not doped with chromium (Cr3+) ions as, although chromium reduces radiation sensitivity, it also considerably reduces the laser's power.

It was therefore decided to use pure laser crystals but to protect them with strong shielding. Optical elements such as lenses or mirrors are also very sensitive to radiation: high doses of radiation can cloud or darken their surfaces. The use of electrically insulating materials such as plastics and polymers was strictly prohibited as the electric charge accumulated by the electron bombardment can cause unwanted electric arcs – as in the case of a balloon rubbed against a piece of clothing – which physically destroy the material.

The telescope's carefully selected surface coatings absorb stray light and reflect the laser signal and their optical properties may be altered by ionisation. It is not possible to shield external surfaces exposed to space, so the selected materials must be inherently radiation resistant. As a result, the telescope parts most exposed to space radiation will be irradiated with several gigarads over the course of the entire mission. This value is almost exclusively reached on Earth within nuclear reactors.

The analogue electronics board separately and in the housing of the transmitter and receiver unit

Our main focus during the development of GALA was protecting the electronics, especially the sensitive detector and laser components. The entire device was designed according to this concept: the sensor and the laser were placed in the centre, and everything else was shaped to create a kind of cylinder (ideally a sphere) around them.

This design required unorthodox solutions: the analogue electronics board (see images below), for example, had to be shaped like a hexagon with a hole in the middle because the detector unit had to be plugged into it.

We sourced very robust electronic components qualified for the expected radiation levels. We often travelled to facilities such as the ELBE centre in Dresden, the GEODUR facility at ONERA in Toulouse or the University of Delft to irradiate custom parts and new technologies with electrons and qualify them for the extreme conditions at Jupiter.

Sectional analysis of the detector reveals how much shielding thickness protects the detector in different directions

However, the selection of radiation-resistant parts and the testing were not enough on their own: additional shielding was still required. For this reason, the GALA housing was built with particularly thick walls. Usually, scientific instruments that will fly to space are designed to be as light as possible. With GALA and all instruments on JUICE, weight had to be traded for radiation hardness. The design of the instrument was revised several times following detailed radiation analyses. The complex interaction between the charged particles and all the components of GALA was simulated using special software. Each stage of development in the design required hundreds – sometimes thousands – of hours of computing time to predict the radiation doses accumulated by all sensitive parts over the course of the mission. These analyses have confirmed that GALA is now capable of surviving and functioning correctly despite the harsh radiation environment at Jupiter.

TrackbackURL

About the author

Simone Del Togno is a thermal and radiation engineer in the Planetary Sensor Systems department at the DLR Institute of Planetary Research in Berlin. His main task is to ensure that the scientific instruments developed here survive and function correctly in space. He contributes to the design and testing of the instrument prototypes. to authorpage

Posts with similar themes

Generated by Readability.php.

GALA on JUICE Part 2 – From the first idea to the finished instrument – a development story

Mon, 27 Mar 2023 10:10:00 +0200

DLR - Blogs - All blog posts

By DLR Blogs

Quelle: NASA/JPL/DLR

Jupiter’s Galilean moons – the target of the JUICE mission

In the first part of this blog series on the Ganymede Laser Altimeter (GALA), we introduced the instrument and its scientific goals. In this article, we will describe the long development history that a complex instrument such as GALA must go through until it can be launched into space.

In 2007, more than 15 years ago, ESA selected a proposal for a Jupiter mission for an ‘Assessment Phase Study’. The idea was to fly to the unexplored icy moons of Jupiter and study their atmosphere, magnetic fields and radiation belts. The mission was named Laplace.##markend##

First block diagram of GALA. The basic structure with a Transceiver Unit for the laser and receiving telescope as well as the Electronics Units can be seen.

The scientific objectives were drawn up in the international scientific community including suggestions on the type of instruments that could be used to obtain the scientific data with the corresponding measurements. A laser altimeter was amongst the many candidates.

In September 2008, at the first payload meeting, we presented the first GALA block diagram, still very elementary and showing only the basic concept.

Here is a first prediction of what the surface coverage could look like, again with very preliminary assumptions regarding the orbital parameters in Ganymede orbit:

Early simulation of the ground tracks on the surface of Ganymede after 12 days in a 200-kilometre circular orbit

In 2009 and 2010, there was an interesting development from a programmatic point of view: NASA had been planning its own mission to Jupiter's moon Europa in parallel to ESA's Laplace mission. The two programmes were combined: there was a Jupiter Europa Orbiter from NASA and a Jupiter Ganymede Orbiter from ESA, formerly Laplace.

The joint programme was called the Europa Jupiter System Mission (EJSM) and the simultaneous presence of the two space probes in the Jupiter system was supposed to complement and enrich the scientific output. A good idea, but unfortunately NASA withdrew from the project in the years that followed for financial reasons. But the story doesn't end here: around 2015, a slimmed-down version of the original NASA mission was born under the name Europa Clipper. It is scheduled to launch in October 2024, arriving in the Jupiter system in 2030. Thus, two probes will travel to the Jupiter system at the same time and will complement each other perfectly. There are even plans for the European JUICE spacecraft to record the US Europa Clipper spacecraft when it impacts the surface of Ganymede at the end of its lifetime, hurling ice and dust into the sky. The particle measurement instruments and spectrometers on JUICE will be delighted, and the laser altimeter and camera will be able to explore a new crater.

But back to GALA in 2009: the calculations for the required performance, especially the link budget, have been constantly refined. Countless technical parameters on optical and electrical assemblies had to be considered, including the ageing of the components during the years-long mission, the characteristics of the detector (a silicon photodiode), the algorithms of pulse detection and so on.

All this was simulated with patchy, often inaccurate data from past Jupiter missions, such as the Galileo mission (mid-1990s), to see if GALA's targeted performance parameters would be sufficient. Of course, this step involves a great deal of uncertainty, since we are flying to unexplored icy moons.

Simulations of the tidal deformation of Ganymede

The calculations led to an initial estimation of the required laser pulse energy of 15 to 26 millijoules (later it will be 17 millijoules) and a diameter of the telescope of 10 to 25 centimetres (it will eventually be 25 centimetres). The hand sketches were finally cast into a first CAD design, taking into account many experiences from our previous laser altimeter project BELA.

For example, the transceiver unit with laser and receiving telescope is built very compactly, which enormously improves the stability of the optical alignment between the laser beam axis and the axis of the receiving telescope. This also reduces the volume of the assembly, which reduces the mass, although the exterior walls have to be comparatively thick for the sake of radiation protection. More on the subject of radiation in the Jupiter system in the third part of the blog series!

First CAD design of the GALA Transceiver Unit

We are able to shorten the electrical transmission path for the weak electrical signal from the detector to the digitising electronics to a few centimetres. Significant improvements were made in the electronics design, and interference from the pump current of 200 amperes for the laser diodes was almost completely suppressed.

The electronics unit contains the current and voltage supply, the rangefinder module for pulse analysis and calculation of the pulse propagation time, the main computer of the instrument (here called ICM) and the laser control module, which was later moved to a separate unit. Here, too, you can clearly see the thick outer walls for shielding and the complete cold redundancy that was still planned at the time.

First CAD design of the GALA Electronic Unit

In the years leading up to 2012, not only were the international GALA consortium (Japan, Switzerland, Spain) and the respective work packages defined. The technical development also progressed rapidly.

The assemblies of the Transceiver Unit were arranged on a stable optical bench: At the very top is the telescope, below it the detector with its detector-related electronics and at the very bottom the laser, whose laser beam was to be emitted towards the lunar surface via a deflecting mirror.

The most important key figures for energy consumption are always the required power and the mass. At that time, with the preliminary design, the values were 47.3 watts and 24.5 kilograms, which hardly differed from the later values of the flight model. Good job!

Further development of the transceiver unit with arrangement of the assemblies

In 2013 and 2014, the GALA project was increasingly integrated into ESA's mission planning; the interfaces to the spacecraft were specifically considered. This was followed by the first reviews with the beautiful names Instrument Preliminary Requirement Review and Instrument Consolidation Review, which were the basis for ESA's invitation to tender for the construction of the spacecraft. In 2015, Airbus became the prime contractor and henceforth another important contact for all parties involved. On the part of GALA, the contractual basis for the coming years was laid with our German industrial partner Hensoldt Optronics (formerly Zeiss Optronics).

In 2015 and 2016, the technical development was pushed full steam ahead in an ever-growing team. In addition to CAD design, mathematical simulation models in the areas of mechanics, thermal design, optics and radiation resistance were created and constantly fine-tuned. The interfaces with the spacecraft were further improved and adjusted. Since radiation-resistant components, coatings and materials are vital for a mission into the Jupiter system, a large number of radiation tests were carried out. Powerful electron beams shot the high-energy charged particles at optics and circuits, which had to survive this ordeal undamaged at best.

Quelle: Hensoldt Optronics

Development of the design between 2015 and 2016

Then, in October 2016, it was time for the first major review by ESA. The Preliminary Design Review examined whether the instrument met all scientific and technical requirements, whether the schedule was coherent and whether preparations had been made for the coming phases of production of the individual parts, assembly and testing.

We successfully passed the review and were thus able to start production of the first GALA models. On the one hand, the Structural Thermal Model (STM) had to prove mechanical stability and required thermal properties. On the other hand, the Electrical Model (EM) was electrically representative and was going to be used for testing the GALA software.

At the same time, this meant that the design of the GALA flight model entered the critical phase, reaching its almost final stage at the end of 2018. This was a particularly intense time, as in addition to building and testing the STM and EM with us and the international partners, the design of the flight model also had to be finalised. The radiation tests were almost complete, and the interfaces with the spacecraft had to be defined down to the last detail.

Design of the GALA flight model at the end of 2018 (from left to right). The Transceiver Unit (with radiator), the Electronic Unit and the Laser Electronic Unit.

Highlights of this phase were three milestones in 2019:

In April, we passed the Critical Design Review with flying colours. This meant that we were given the green light to build the flight model. In June, we were able to complete the tests of the STM and deliver this model to ESA/Airbus, as well as the EM in August. Phew!

The year 2020 turned out to be completely different than we could have ever imagined. Normally, in this phase of assembly and testing of the flight model, the goal involves working intensively in the lab directly on the hardware, but Covid-19 shattered this planning.

Staff in the lab had to be reduced to the absolute minimum and work was done in shifts. We installed webcams in the lab so that we could carry out the work in a 'hybrid' way from the home office with colleagues in the lab. Almost every control computer was made remotely controllable – often at the pain of our IT department.

The schedule was already enormously tight at this point. We had planned through all the activities for the next 12 months to the day. ESA and Airbus did not allow any delay. The GALA team pulled together, was flexible and managed to complete both electronics units of the flight model in June 2020 and then the transceiver unit in October 2020.

Credit: see image descriptions

Figure 1: Analogue electronics module from Japan. It amplifies and digitises the detector signal and is built into the transceiver unit. Credit: JAXA

Figure 2: Electronic Unit in ‘stretched configuration’ during the integration phase. Credit: © DLR

Figure 3: Capacitor banks inside the Laser Electronic Unit. This is where the energy is stored that is used to generate the very short laser pulses of five nanoseconds. Credit: Hensoldt Optronics

Figure 4: Flight model of the Transceiver Unit shortly before assembly is completed. Credit: Hensoldt Optronics

Figure 5: Flight model of the Electronic Unit. Credit: © DLR

Figure 6: Flight model of the Laser Electronic Unit. Credit: Hensoldt Optronics

It was time to rigorously test the complete flight model. This was done in the following ten months until August 2021. Still under Covid-19 restrictions, we performed EMC tests, including AC magnetic tests, vibration tests, thermal cycling and balance tests, DC magnetic tests, software tests and many others.

On 14 August 2021, the big moment arrived: the extensive test campaign was over. ESA and Airbus reviewed, accepted and approved the test results and agreed to deliver the GALA flight model towards Toulouse to Airbus. Again, phew! The next major stages were the integration of GALA onto the JUICE spacecraft and the test campaign that followed.

A summary can be found here. GALA also completed this 15-month phase successfully and proved its full technical performance. Now we are optimistic that we will gain excellent scientific data during the mission.

TrackbackURL

About the author

Posts with similar themes

Generated by Readability.php.