European Space Agency Technology Research Articles

Measuring Intracellular Viscosity in Conditions of Hypergravity

Gravity-sensitive cellular responses are regularly observed in both specialized and nonspecialized cells. One potential mechanism for this sensitivity is a changing viscosity of the intracellular organelles. Here, we report a novel, to our knowledge, viscosity-sensitive molecular rotor based on mesosubstituted boron-dipyrrin used to investigate the response of viscosity of cellular membranes to hypergravity conditions created at the large diameter centrifuge at the European Space Agency Technology Centre. Mouse osteoblastic (MC3T3-E1) and endothelial (human umbilical vein endothelial cell) cell lines were tested, and an increase in viscosity was found with increasing hypergravity loading. This response is thought to be primarily biologically driven, with the potential for a small, instantaneous physical mechanism also contributing to the observed effect. This work provides the first, to our knowledge, quantitative data for cellular viscosity changes under hypergravity, up to 15 × g.

Building Polish space sector – from small islands of excellence to a national innovation ecosystem

In the paper a national potential of Poland to build its space industry after joining the European Space Agency (ESA) in 2012 is assessed, based on the series of survey reports published annually by POLSA since 2016. Their methodology was based on the ESA technology tree, classifying all the space-related technical knowhow and allowed identification of the most promising strengths to exploit and shortages to challenge by policymakers implementing up to the 2030 horizon the Polish Space Strategy adopted by the Polish Council of Ministers in 2017.

Framing in European space policy

In the paper a national potential of Poland to build its space industry after joining the European Space Agency (ESA) in 2012 is assessed, based on the series of survey reports published annually by POLSA since 2016. Their methodology was based on the ESA technology tree, classifying all the space-related technical knowhow and allowed identification of the most promising strengths to exploit and shortages to challenge by policymakers implementing up to the 2030 horizon the Polish Space Strategy adopted by the Polish Council of Ministers in 2017.

Special issue on main results of Call‐off Order 3 (CoO3) in SatNEx III

Special issue on main results of Call‐off Order 3 (<scp>CoO3</scp>) in <scp>SatNEx</scp> III

Modeling and performance of contact-free discharge systems for space inertial sensors

This article presents a detailed overview and assessment of contact-free ultraviolet light discharge systems (UVDSs) needed to control the variable electric charge level of free-flying test masses, which are part of high-precision inertial sensors in space. A comprehensive numerical analysis approach on the basis of experimental data is detailed. This includes ultraviolet light ray tracing, the computation of time variant electric fields inside the complex inertial sensor geometry, and the simulation of individual photoelectron trajectories. Subsequent data analysis allows determination of key parameters to set up an analytical discharge model. Such a model is an essential system engineering tool needed for requirement breakdown and subsystem specification, performance budgeting, onboard charge control software development, and instrument modeling within spacecraft end-to-end performance simulators. Different types of UVDS design concepts are presented and assessed regarding their robustness and performance. Critical hardware aspects like electron emission from air-contaminated surfaces, interfaces with other subsystems, and spacecraft operations are considered. The focus is on the modeling and performance evaluation of the existing UVDS onboard the LISA Pathfinder, a European Space Agency technology demonstrator spacecraft, which is in implementation phase. The results have motivated the design of a more robust discharge system concept for cubical test mass inertial sensors for future space missions. The analysis tools developed have been used for design optimization and performance assessment of the proposed design. A significant improvement of relevant robustness and performance figures has been achieved.

The technology management process at the European space agency

Technology is developed at the European Space Agency (ESA) under several programmes: corporate and domain specific, mandatory and optional, with different time horizons and covering different levels of the TRL scale. To improve the transparency and efficiency of the complete process, it was felt necessary to establish an agreed end to end process for the management of all technology R&D activity that could: 1. Include all ESA programmes and consider the requirements of European users 2. Lead to coordinated multi-year work plan and yearly procurement plans 3. Prepare and enable future European space programmes 4. Be harmonized with national initiatives in Europe Thereby establishing the basis for a product policy to reduce risks to technology users, reduce costs and delays, and enhance industrial competitiveness and non-dependence. In response to the above needs, ESA has developed a technology management process called the ESA End-to-End process (E2E), from establishment of the strategy to the monitoring and evaluation of R&D results. In this paper, the complete process will be described in detail including a discussion on its strengths and limitations, and its links to the wider European Harmonization process. The paper will be concluded with the introduction of the ESA Technology Tree: a basic tool to structure and facilitate communication about technology issues.

Europe Forges a Plan in Collaboration With Industry

[ Helen Gavaghan ][1] Last month, a European Space Agency (ESA) task force outlined a new strategy for supporting Earth-observation missions that would make industry a full partner in designing, developing, and funding an entire class of missions. The proposal, previewed at a crowded meeting of industrialists at ESA's science and technology center in Noordwijk, the Netherlands, on 18 December, would divide future Earth-observation programs into two types: scientific mission, which would be fully paid for out of ESA's budget, and applications missions, which would be private initiatives or risk- and cost-sharing partnerships between the agency and industry, which ESA would join only if the industrial sponsors already have purchasers for their data lined up. This new plan, which will be fleshed out at ESA headquarters over the next few months and presented to the organization's member states this summer, is designed to fill a looming gap in ESA's Earth-observation program. [1]: http://www.sciencemag.org#name

Some Recent European Satellite Antenna Developments

ESTEC, the European Space Agency Technology Centre, is contributing to the development of modelling tools and technologies for use in the design of antennas or European safellites. Over the next few years, their designers will be working on the reduction of costs and the development of new technologies including submicrowave techniques, optical components and integrated active antennas.

Some European satellite-antenna developments and trends

The environment, as well as the mass and available power limitations specific to space missions, add special constraints. These lead to the use of exotic low-mass, high-stability materials, with advanced mechanical and thermal designs. Also, antenna front ends must be tailored for optimum efficiency and power handling. Researchers and engineers in universities, research institutes, and industrial laboratories, from the 14 member states of the European Space Agency (ESA), together with staff from the European Space Agency's Technology Centre (ESTEC) antenna section and from project teams, have studied and developed software-modeling tools, critical reflector and array technologies, novel antenna architectures, and special measurement techniques to cope with these requirements. This paper presents an overview of some of the latest antenna-design tools and technology developments, supported by ESA for space applications. The following topics are covered reflectors, feed systems, and direct-radiating arrays. Some trends and developments in space antenna requirements and technologies are outlined.

The SILEX optical interorbit link experiment

The implementation of communication links between a low earth-orbiting satellite and a geostationary one, or between two geostationary satellites, will lead to significant improvements in the performance of space communication systems. Optical technology is attractive for these applications when high-data-rateCommunication is required. The European Space Agency (ESA) has therefore instigated and in-ordbit demonstration project known as SILEX (semiconductor laser intersatellite link experiment) using a pre-operational link between the French SPOT-4 low earth orbit satellite and the ESA Advanced Relay and Technology Mission Satellite(ARTEMIS). Such and optical communication system brings some new and challenging requirements. In particular, the communication beam, which has a divergence of around 6 μrad, must achieve and maintain a very demanding pointing accuracy in the presence of both host satellite vibration and relative satellite motion. This paper provides an overview of the SILEX project and describes a novel pointing mechanism.