Ernst K. Pfeiffer: Summary of the Zero Debris Symposium and Workshop
HPS Space News
Ernst K. Pfeiffer: Summary of the Zero Debris Symposium and Workshop on the Zero Debris Booklet – an ESA/ESOC initiative in Darmstadt
Great: the Zero-Debris Symposium and Workshop on the Zero-Debris Booklet brought a full house to ESA’s European Space Operation Center from June 10 to 12. The program covered all relevant aspects of the topic with slots for exchanging experiences on developments over the last 12 months, panel discussions such as “Zero Debris Progress & Challenges” and presentations such as the one by HPS CEO Ernst K. Pfeiffer on “How we work with the Zero Debris Booklet”. HPS High Performance Space Structure Systems GmbH is one of the central suppliers in this “clean space” sector – but not only that: it is also one of the driving industrial forces when it comes to making space travel sustainable. To this end, the company has been investing heavily in corresponding technologies for over ten years and today covers the demand for towing sail modules (ADEO), is working on deployable membranes for the in-situ measurement of small debris (SAILOR) and has recently developed non-reflective films (ProFilm) for “dark skies”. At the end of the event, Pfeiffer summarized his summary in the following positions:
- The Zero Debris Charter and the 5-year deorbit rule introduced by ESA for all its new missions is important for strategic planning in companies and motivates further investment in corresponding technology developments.
- The mindset of satellite manufacturers and operators with regard to deorbit approaches has changed fundamentally over the past 18 months, with more and more satellite manufacturers turning to hybrid and redundant solutions.
- In the early phases of national and ESA missions, a specific trade-off between different deorbit technologies should be performed; the recommended trade-off criteria should be part of the Zero Debris Booklet.
- To promote the goals of the Zero Debris Community in Europe and worldwide, simple KPI graphs should visualize the – hopefully positive – development of the debris situation, such as the average deorbit time, the number of satellites lost due to anomalies (according to NASA, it is currently more than 40% of small sats!) and the number of collision maneuvres.
- An anchor customer for suppliers of zero-debris equipment or vouchers for satellite builders for on-board zero-debris technology should be part of the CMin25 program (e.g. 10 MioEUR/year, in packages of 100k)
- A redefinition of “end-of-life”, “end-of-mission”, “end-of-business” needs to be made now if deorbit time to complete demise is to be part of the mission today; the definition needs to be crystal clear in potential future courts.
- It is time to study the effects of the exhaust gases produced by thousands of propellant-based deorbit maneuvers that could affect high-resolution optical Earth observation missions (including military ones) in 5-10 years.
- A step-by-step approach with a gradual implementation of small zero-debris targets is better than endless discussions about perfect regulations and technologies with the requirement to satisfy all stakeholders at the same time.
Pfeiffer particularly emphasized the positive spirit of optimism of all participants, which was carried and spread by the space giants such as TAS and OHB, the midcaps such as GMV or FEV etamax, as well as NewSpace companies such as D-Orbit, RIVADA, VYOMA, Astroscale, Clearspace, investors, lawyers, institutes, EIC and national space agencies. Special thanks went to the organizers from ESA’s Space Safety Department, in particular Quentin Verspieren, Sacha Bressollette and Calum Turner.


HPS prominently present at ESA’s Zero Debris Week
From 10 to 12 June 2025, everything at ESA’s European Space Operations Center in Darmstadt will be dominated by the highly ambitious “Zero Debris Program” of Europe’s space agency. The days are divided into two large action chapters: from June 10-11 at noon, the Zero Debris Future Symposium will focus in particular on high-level discussions of non-technical aspects, such as the future direction of the Zero Debris Initiative and its community, as well as commercial and political challenges in connection with orbital debris. Day two, June 11-12 at noon, will be dedicated to another working session on the Zero Debris Technical Booklet. Among other things, the technical leaders who will oversee the next edition of the booklet will be elected on this occasion. The participating organizations will also discuss how they have used the booklet so far, how the work on the booklet should be regulated and organized, and how the technologies listed in the booklet can be implemented.
The Zero Debris Technical Booklet published on January 15, 2025 lists technologies that ESA believes will contribute to achieving the goal of zero debris by 2030. The booklet is essentially a technical zero debris “to-do list”. The aim is to minimize the release of new debris and reduce its impact on people, infrastructure and the Earth’s environment.
Developed by a team of engineers, operators, lawyers, scientists and policy experts from a wide range of institutions in the Zero Debris community, the booklet identifies six key technology objectives that are essential to achieving Zero Debris goals:
- Preventing the release of new debris at any scale, from small particles to missile parts.
- Preventing the creation of debris from collisions or breakups.
- Improve monitoring and coordination of space traffic.
- Immediate evacuation of satellites from important low-Earth and geostationary orbits at the end of their mission.
- Preventing damage to the ground after re-entries.

ESA itself is focusing its efforts on the development of debris-resistant materials and technologies, the design of satellites that can be easily removed from orbit and do not burn up on re-entry into the atmosphere, and finally the development of standardized interfaces for efficient removal in the event of a malfunction.
Beyond the satellite itself, the focus is also on new systems to remove all components of the launch vehicle from orbit. Another source of debris are small particles released by certain types of fuel and pyrotechnics in orbit during deployment. Alternatives are to be developed for this. The distribution of space debris around the Earth highlights the importance of collision avoidance measures. Once the satellites are in operation, much can be gained by optimizing collision avoidance processes and space traffic management. A key element is improving tracking capabilities for smaller, currently untrackable debris objects to refine risk assessment.
Operational practices can also be optimized, supported by new technologies to improve communication infrastructure and spacecraft health monitoring. At the end of a mission, the deorbit and re-entry process (for LEO and MEO satellites) and the impact on the environment need to be considered. Active debris removal services are required in orbit, as well as reducing the environmental impact of debris re-entry on the ocean and atmosphere, which will begin with further research.
Participation in ESA’s Zero Debris Initiative is a top priority for HPS – and accordingly, HPS CEO Ernst K. Pfeiffer will take part in the central program items on both days in Darmstadt. HPS’s commitment goes far beyond academic aspects, as the company has already made a remarkable contribution to avoiding space debris with its ADEO Deorbit Module product family by rapidly removing disused satellites from orbit; in addition, it is already on the threshold of Phase B with initial developments for a detector for previously undetectable particles from 0.1 to 10 mm in size called SAILOR.
The HPS boss doesn’t mince his words when it comes to emphasizing the importance of the ESA initiative: “The Zero-Debris Initiative is a start, but we are still a long way to our goal. We still have to reach an important milestone, and that is directly in the minds of the target groups: In parts of the space community, the debris issue is still seen as merely a green nice-to-have topic. This is absolutely wrong: it is an issue of great commercial interest and value, because if the littering of orbits continues at this rate, economically viable activities in space will soon be history – and that so before they have really taken off.”
HPS puts ADEO know-how at the service of ESA´s Hungarian Prime C3S
It seems to be a basic law of nature: Wherever and however humans are active, they end up producing large quantities of waste. To suppress the problem, many terrestrial areas, the oceans and, in recent decades, outer space itself have become dumping grounds. However, the latter in particular is now threatening to take radical revenge, as flying debris from previous space missions is increasingly becoming a threat to all other activities, especially in the most frequented orbits between 200 and 1200 kilometers.
While large debris such as burnt-out rocket stages are the easiest to detect and can be avoided by new guests in orbit, it is the small projectiles, flying with 5-10 km/s orbital speed, which have often shrunk below millimeter size as a result of previous fragmentations, that pose the greatest threats. Even one millimeter-sized debris impact can render a satellite inoperable. Emerging their threat further, their flux increases significantly as their size decreases, with the consequence that the much more frequent impacts of debris of this size can pose a far greater risk to space operations than the more dramatic catastrophic incidents.
However, only larger debris can be observed and tracked from the ground – but not in the critical range of 0.1 to 50 mm. Therefore, measurements in situ, i.e. directly in orbit, are urgently needed to make it possible to describe the Earth’s flying garbage dump with sufficient reliability in the first place. After critically weighing up the alternatives, ESA has turned its attention to a possible large-area detector based on the successful ADEO deorbit sails from HPS. If the sail membranes are now equipped with acoustic sensors and cameras on board, it will be possible to measure the dust flow in the required size range. The name of the project: SAILOR – Sail Array for Impact Logging in Orbit.

The spacecraft consists of two large detector surfaces 100 cm apart. The two sails have an exposed surface area of 25 m2; in the ADEO program, they are the main actors of the large dragsail versions under the name ADEO-L. The membranes are around 10 μm thick and are held in position by extendable cross booms. The booms are stowed together with the sail membranes during launch and deployed in orbit. The deployment module in which booms and sails are integrated, consists of a deploying mechanism with a motor that pushes the boom arms outwards. A system of multiple cameras is mounted to a separate boom to document the holes created on the inner surface of both sail membranes. Acoustic sensors are attached to the sails to detect an impact in real time. The interaction of SAILOR’s technical equipment will ultimately allow the density, speed and trajectory of the small debris to be determined.
The ambitious ESA project SAILOR is currently in the transition from Phase A to Phase B1, which will also include the construction of breadboard models of the spacecraft and its electronics as well as the associated test programs. It also involves these steps:
- Production of test samples of the proposed membrane equipped with the acoustic sensors
- Tests of sail folding for stowage
- Testing of the boom and sail deployment mechanisms
- A high-speed (hypervelocity) impact test program to test the sails and sensors
- Testing a camera system to image holes in the sail
- Preliminary design of the spacecraft including suppliers for all critical components and subsystems. PDR is currently planned to be achieved until 2028.
Overall, the specifications of the project in this phase should lead to a positive decision at the ESA Ministerial Council meeting in Bremen in November 2025 on the continuation of a three-year mission at an altitude of 850 km to be launched in 2031/2032. The industrial team proposes a small precursor CubeSat mission, called OPTIMIST after this type of sailboat, to test the sensor technology using an approx. 10 m2 membrane as early as 2027/2028 as risk mitigation for the full-scale mission.
The industrial structure behind SAILOR also stands for this. This is because C3S, a leading Hungarian aerospace company, is acting as prime contractor for an ESA project of this kind for the first time, drawing on the expertise of ADEO inventor HPS GmbH as a subcontractor for the deployable membrane subsystem. C3S is also planning work shares for HPS in Romania. HPS CEO Ernst K. Pfeiffer: “The great enthusiasm with which we have taken on our role in this project rests on three pillars: firstly, it is existentially important for the space industry as a whole; secondly, it is an opportunity for us as HPS to impressively demonstrate the versatility of the ADEO technology from our company; and thirdly, we consider it eminently important in Europe that the industrial talents of Hungary and Romania are finally brought to light in an appropriate way, and that in a joint mission. We at HPS are delighted to be working under the project management of C3S.”
CIMR-LDRS: The lighthouse project for non-dependence in European space travel enters the production phase of the qualification model (EQM) as planned
CIMR-LDRS: The lighthouse project for non-dependence in European space travel enters the production phase of the qualification model (EQM) as planned
Long before an unspeakable bloodbath sealed the end of peaceful life in Eastern Europe in 2022, the demand for technological “non-dependence” had already conquered a top position among the strategic priorities in German and European space travel. The focus was particularly on large reflector antennas that could be deployed in space, suitable for missions of all kinds.
The history of this German technology for Europe began more than a decade ago with SCALABE, a technology development funded by ESA, and SMERALDA (SME’s Radar and Large Deployable Antenna), a study funded by the German Space Agency with significant participation by antenna specialist HPS GmbH. Through further technical chapters of successful concretization of the goal with significant support from ESA and the EU, the Munich-based company finally led a consortium of mostly medium-sized partners from eight countries to the spectacular win of the 115 million euro contract from Prime`sThalesAlenia Space (TAS) for “CIMR LDRS” (Large Deployable Reflector Subsystem) in 2020: the world’s largest rotating deployable reflector antenna construction for the EU’s Copernicus Imaging Microwave Radiometer (CIMR) lighthouse project for observing land, ice and oceans, particularly the Arctic, from space under the management of the European Space Agency (ESA). The LDR subsystem consists of a reflector, arm, deconvolution electronics, cabling, various hold-down mechanisms and thermal hardware.
After a long design phase and intensive iteration with the direct customer TAS in Rome and the end customer ESA, the go-ahead was given in phase C/D with the completion of the first so-called “Manufacturing Readiness Review” for the construction and testing of a qualification model (Engineering Qualification Model, EQM). In these days of spring 2025, HPS has now finally entered the intensive phase of manufacturing the EQM.
Challenges on the way to new shores
The technical challenges were and are immense, as the goal is nothing less than a deployable reflector construct for high frequencies (Ka-band) with a diameter of eight meters on an equally deployable eight-meter-long arm that rotates around its own axis eight times per minute in orbit. This results in extreme requirements such as an RMS (Root Mean Square) value for the surface accuracy, which must be much smaller than 1/10 mm over the entire 50 m² reflector surface, or a maximum permissible deviation of the 8 m distant arm tip of just 10 mm from the nominal value, including vibrations, centrifugal force and thermal deformations.
The challenges of managing the various aspects of the project were and are no less demanding. The program management of the CIMR team from ESA and TAS has played a prominent role from the outset, while HPS GmbH, known for its heritage in institutional, military and commercial antenna construction – in addition to its own development work at arm and subsystem level – is responsible for managing the consortium of around a dozen SMEs, including such outstanding innovation drivers as Munich-based LSS GmbH for the deployable reflector assembly (DRA), based on a highly successful, long-standing development partnership. The lightweight carbon struts for the DRA come from the former Portuguese HPS subsidiary and now FHP, INVENT GmbH contributes the carbon fiber-reinforced tubes for the 8-meter deployable support arm (DAA), NanoSpace Switzerland develops and produces the high-precision yet stable, motor-driven joints of the arm, HPS Romania and INEGI Portugal the constructions for ground tests and transports (“MGSE”). In addition, HPS is responsible for providing the central element for the deployable reflector: the measurably best Ka-band MESH from HPtex that is available to buy in a 9m x 9m size – and, as a “made in Germany” product, transforms European non-dependence from vision to reality. Until then, a MESH in such dimensions had only been available in American production. Originally planned as an essential element of the German-European supply chain for CIMR, the joint venture HPTex GmbH (JV of Iprotex GmbH & Co. KG and HPS GmbH), founded in 2020, now sells its mesh products worldwide, especially in Asian and continental American countries. The EQM mesh for CIMR recently came out of HPtex production.
The most important components (DAA and DRA) will be ready by the end of the year, and the series of tests will begin early in 2026.
“If you want to be ahead, you shouldn’t be afraid of the unknown” (Ernst K. Pfeiffer)
When CIMR sets off on its mission in 2029 on board a Vega C in a sun-synchronous orbit to observe ice sheets and snow, among other things, from dawn to dusk, Europe will not only benefit from the knowledge gained from the project, but also from the certainty of having mastered the step towards technological LDRS independence. LDRS are also products for a range of military applications that can contribute to an increased defense capability, especially in these years. HPS CEO Ernst K. Pfeiffer sees this as a milestone that goes far beyond the immediate success of the project: “This space project is clear proof that the mentality of all those involved in the project – both industry and institutions – is completely different to the risk aversion that the public normally attributes to Germany in particular, and to some extent also to ESA. Not being afraid of the unknown is the first key to success. Way up front is where it´s getting dark. Especially in space. But not only there.”

Pushing the limits of what’s possible in CubeSat technology – for science, for Earth, for the future
We are thrilled to announce that HPS GmbH has been awarded a new Technology Activity by the European Space Agency (ESA)! The contract signature has been taken place on 08.04.2025.
In this groundbreaking GSTP-project, we will develop a cutting-edge CubeSat deployable ArrayAntenna in collaboration with our esteemed partners at Fraunhofer-Gesellschaft (IIS, Germany). This innovative technology, known as MANT (Miniaturized Deployable Antenna for Small and Nanosatellites), will reach TRL6 by the end of the project, marking a significant advancement for the capabilities of small and nanosatellites focussed to civil Earth Observation applications, which always would enable also “Dual Use”. The project is fully funded with a budget of 750,000 euros and will run for two years.
We are excited to contribute to the next generation of satellite technology, advancing small satellite communication with more efficient, compact, and powerful solutions. Stay tuned for updates such as for detailed geometries (in stowed configuration: less than 1U), frequencies and interfaces, as we never stop working towards transforming space technology!
Next Milestone: Requirements Review by end of May.

A full success: the “Space Day” at HPS
A full success: the “Space Day” at HPS
On March 28, 2025, HPS in Munich opened its doors to space enthusiasts and those who might want to become one – and it was a great success! We welcomed numerous guests who took part in our guided tours, presentations, Q&A sessions and workshops with great interest. We were particularly pleased about the visit of Ministerial Director Dr. Markus Wittmann and MRin Anne Köster from the Bavarian State Ministry of Economic Affairs, who came to get a personal impression of our work in Bavaria (Munich and Münchberg in Upper Franconia).
The entire day was characterized by innovation, thirst for knowledge and enthusiasm for space travel. Our guests were given exclusive insights into our products, expertise, processes, test laboratories and clean rooms. Our experts gave exciting introductions to the world of e.g. satellite communication, earth observation and manned space flight and their space technologies. Our CEO, Dr.-Ing. Ernst K. Pfeiffer, gave a presentation on “Why space travel?” in the early afternoon and in the evening, also providing insights into the latest news in global space travel.
The crowds were large and the curiosity of our visitors was overwhelming – every guided tour and every lecture was followed with great interest.
The consistently positive feedback was particularly pleasing: many participants praised the opportunity to experience space travel up close and learn more about HPS technologies. This great response reinforces our goal of sharing not only our fascination for space but also its necessity for Germany and Europe.
With this success, we are very optimistic about the future and hope that after a few years there will be another nationwide “Space Day” to spread the enthusiasm for space travel together with you!
Many thanks to everyone who took part and made this day possible! See you soon!
HPS with ADEO product family: top position in NASA’s technology report extended
A year ago, the deorbit module from HPS took its place at the top of the podium of the most important technology achievements according to NASA. This was because ADEO already had everything that the American space agency considered crucial for success at the time: top values up to TRL9, scalability and proven flight heritage. Exactly one year later: ADEO, now supplemented in the technology report by the presentation of the bestsellers ADEO-Cube and ADEO-Pico, maintains its position both against numerous Dragsail competitors and against other passive deorbit technologies.
HPS CEO Ernst K. Pfeiffer comments: “With ADEO, we are surfing at the top of the wave worldwide that we have created ourselves with this technology over many years of R&D – often with significant co-financing by ESA and DLR plus considerable company resources. And we are actually delighted with every attempt by other companies to establish deorbit sails on the market: The bigger they make the wave, the higher our product family sails on its crest.”

Two HPS contributions on board the Transporter 12 mission on January 14, 2025
Even HPS has never done this before: two of the company’s products are on their way to a sun-synchronous orbit on a Falcon 9 mission. This has been made possible by the rideshare- version of the SpaceX rocket named “Transporter 12”.
On the one hand, the contributions from HPS relate to the highly innovative BANT-1 reflector antenna for Reflex Aerospace’s premiere satellite – see also the HPS news item “HPS congratulates Reflex Aerospace” from today, January 14.
On the other hand, a contribution from HPS itself is the premiere. For the first time, HPS Germany and HPS Romania have jointly prepared a flight hardware with the MLI insulation of the central radiator in such a way that the thermo-optical properties of the satellite are maintained even under the most adverse conditions in space.
The satellite is Sky Bee-1 and part of a thermal infrared constellation HiVE that provides highly accurate yet cost-effective daily temperature data of the world’s land surfaces with a resolution of 30 meters for the benefit of agriculture, urban and industrial environments. The HPS teams of both European countries warmly congratulate their client OHB on the launch success. The first flight model SkyBee-1 is being developed under the InCubed Programme, co-funded by the European Space Agency.


Space premiere also for the innovative BANT-1 reflector antenna from HPS
On January 14, 2025, “SIGI”, the first satellite from the NextSpace company Reflex Aerospace, Berlin/Munich, was launched on board a Falcon 9 – Rideshare Mission Transporter-12. “NextSpace” is the term legally reserved for exclusive use by Reflex to describe the new speed in the development, production and provision of space technology, coupled with innovative versatility as a leitmotif for the performance of the product.
To a large extent, this also applied to an essential element of the satellite not manufactured by Reflex: the core broadband reflector antenna developed by HPS from the medium-sized space technology company HPS GmbH (Munich, Germany) with a cavity-backed spiral antenna as an axial feed for a wide bandwidth and considerable gain – and all that from order to delivery in just 12 months.
HPS congratulates Reflex Aerospace on the first launch of one of its products and looks forward to working with them on further NextSpace challenges in space.

Pictures by SpaceX
Antenna specialist HPS conquers new territory in RF applications with verification of innovative 3D production
Even formerly very sceptical augurs of space travel now agree that the ability to largely automate the series production of lightweight components while minimizing raw materials and ensuring maximum reliability will have a significant impact on the future development of applicable technologies.
However, the central prerequisite for the implementation of such visions is still a very classic step-by-step verification, in this case of two materials selected by the HPS engineers using the new ESA standard ECSS-Q-ST-70-80C.
Given the future potential of such technology, the European and German space agencies have a primary interest in the success of the research at HPS and provided GSTP funding for the 3DPAN2 project: “3D-Printed Antenna 2” is a follow-up project to 3DPAN, which was completed five years ago and initially demonstrated the feasibility in principle of 3D-printed RF components.
The product objective was an extremely lightweight X-band antenna with a diameter of ~30cm for the data downlink of earth observation satellites. It was finally manufactured from the aluminum alloy SCALMALLOY at the sub-contractor APWORKS GmbH in Ottobrunn. In addition, a filigree feed support bracket made of titanium was manufactured for fold-out antennas by the long-standing HPS trusted partner, the Fraunhofer Institute for Material and Beam Technology IWS, Dresden, as a subcontractor.
Meanwhile, the respective designs and FE analyses, as well as their iterative optimization, were carried out by HPS in Munich itself.
The final tests delivered positive results that exceeded all expectations. This applied in particular to the RF performance of the X-band antenna in the Compensated Compact Range (Munich University of Applied Science MUAS). Resistance to vibration (sine + random) was also successfully demonstrated for both demonstrators at SGS GmbH, Geretsried: here too, everything went without complications, i.e. above all without damage or deformation. Even a final TVAC test (10 cycles between +120°C and – 120°C) showed no cracks or deformations on the demonstrators.
Olaf Stolz, the responsible project manager at HPS, summed up the project as follows: “The objectives of the verification processes were achieved without any restrictions: the additively manufactured demonstrators were 20% and 25% lighter than corresponding conventionally manufactured components – a well-known enormous advantage in space travel. There were no restrictions on qualification for space applications. We would like to thank our cooperation partners, especially Dr. Samira Gruber (Fraunhofer IWS) and Mr. Nicklas Schwab (APWORKS) for the extremely good and successful cooperation in the project, as well as ESA, in particular Ms. Isabel Olaya Leon, Technical Officer of the 3DPAN2 project.
HPS CEO Ernst K. Pfeiffer is delighted: “It is fantastic that we are already implementing 3D printed components with the technology results of the ESA GSTP program in current flight projects. A goal that we set 8 years ago and that is essential for the future market has now been achieved.”


