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ANITA (Analysing Interferometer for Ambient Air) is a flight experiment precursor for a permanent continuous air quality monitoring system on the ISS (International Space Station). For the safety of the crew, ANITA can detect and quantify quasi-online and simultaneously 33 gas compounds in the air with ppm or sub-ppm detection limits. The autonomous measurement system is based on FTIR (Fourier Transform Infra-Red spectroscopy). The system represents a versatile air quality monitor, allowing for the first time the detection and monitoring of trace gas dynamics, with high time resolution, in a spacecraft atmosphere. ANITA operated on the ISS from September 2007 to August 2008. This paper summarises the results of ANITA's air analyses and compares results to other measurements acquired on ISS during the operational period.

ECOSIM is a software tool for continuous simulation of systems which makes possible a combined representation of different physical aspects of a system, such as fluid flows, chemical reactions, electrical phenomena, and analogue and digital controls, in a single model. ECOSIM is a true modular simulation tool. The user can easily develop re-usable submodels and libraries of parametric components in the ECOSIM language and by taking advantage of the abstractions provided by the program. It is also possible to call FORTRAN or C subroutines. Mathematical modelling is based on an underlying differential algebraic equation solver, which overcomes the common drawbacks of simulators based on ordinary differential equation solvers. This permits very rich equation sets to be employed in the model which in turn opens the door to multi-disciplinary simulation. These capabilities make ECOSIM a very powerful tool for the simulation of Environmental Control and Life Support Systems (ECLSSs).

In the frame of contracts to ESTEC an advanced adaptive high temperature insulation and an innovative safety enhancing secondary protection have been developed and tested by HPS. Both solutions can be used together to create a new thermal protection concept in order to make it lighter, cheaper and safer.

After 11 months of successful operation onboard the ISS US laboratory Destiny, the air quality monitors ANITA (Analyzing Interferometer for Ambient Air) was brought back to Earth on STS126 (ULF2). ANITA is a technology demonstrator flight experiment for continuous air quality monitoring inside the crewed cabin of the ISS with low detection limits and high time resolution. For the first time, the dynamics of the detected trace gas concentrations could be directly resolved by ANITA and correlated to gas events in the cabin. The system is the result of a long term ESA technology development programme initiated more than seventeen years ago. The ANITA mission was a cooperative project between ESA and NASA. ESA's responsibilities were the provision of the H/W, the data acquisition and the data evaluation. NASA was responsible for the launch, accommodation and operation onboard ISS, data download and the transportation of ANITA back to the Earth.

This paper reports on the thermal testing of METOP (METerological OPerational satellite) Payload Module Engineering Model, conducted in May/June 2001 at ESTEC’s Large Space Simulator (LSS). The paper describes the logic for the selection of the test configuration, the test phases and the performed test sequences. The test results are presented and the correlation results between predicted and measured temperatures are discussed.

Presently, Europe is faced with the task of implementing the Columbus Space Program. In a stepwise approach the Columbus Initial Orbital Configuration will involve eventually into a European (permanently) Manned Space Infrastructure. Towards this goal, various technological challenges arise for the Environmental Control and Life Support System (ECLSS). Some of these have already been identified and are subject of initial investigations. To regain oxygen from the metabolic process, a physico-chemical chain of CO2-concentration, CO2-cracking and water electrolysis is under development. The present status of the preliminary breadboarding, composed of a steam desorbed solid amine concentrator and a Sabatier reactor will be discussed. The third item in this chain, the electrolyser, is not yet implemented in this breadboarding but is under test, demonstrating the technology for regenerative fuel cell application.

Since 1975 ESA's TRP activities in the cryogenic domain have been steadily increasing. Before 1986 most of these activities were directed towards the development of cryogen technology. CRHESUS (CRyostat a HElium Superfluide pour Utilisation Spatiale) was a programme which helped develop superfluid helium technology within Europe. Since 1986 however a major step forward has been made in cryocooler technology, with an 80K cooler developed under TRP funding being recognised as the first viable space cryocooler. It is presently being sold by BAe (UK) as a commercial product. While keeping the basic design these cryocoolers are continuing to be developed down to lower temperatures. Coolers at 20K, 4K and 2.5K exist with 0.1K foreseen. Other cryogenic activities are discussed in the paper and the overall logic and direction of ESA's cryogenic TRP developments explained.

ECOSIM, a software tool for the simulation of ECLSS which has been developed for the European Space Agency (ESA), provides a powerful, friendly graphical interface to users. To test and verify the evolutional capability of ECOSIM for the simulation of ECLSS for future missions, and also to clarify the required future improvements to ECOSIM, the ECLSS of a Moon base, in its initial build-up phase, has been modelled and simulated, following the establishment of the necessary new component mathematical models, including biological ones.

With the successful retrieval of EURECA, the EUROPEAN RETRIEVABLE CARRIER, again a long term orbit satellite (11 month in space) is available for the space material community to investigate the influence of low earth orbit environment on materials which stayed in orbit for a prolonged time. EURECA, designed, manufactured and launched to carry out numerous experiments in the fields of fluid- and solar physics, materials science, biology and astronomy under orbital conditions, in parallel presents a huge material expositon experiment in itself, providing detailed insight into the possible orbital degradation mechanisms due to the synergistic effects of atomic oxygen, UV radiation, thermal cycling, high vacuum and micrometeorite/debris impacts. In order to exploit the valuable information, an integrated ESTEC/ERNO team has been established to perform a detailed investigation of the EURECA surface and - as far as accessible -internal structural parts and experiments.

When gas conductance/natural convection plays a major role as heat transfer path, microporous insulations reveal distinct advantages compared to Multi-Layer Insulations (MLI). For re-entry vehicles as e. g. HERMES or capsules silica and ceramic microfiber insulations have been investigated by DASA/ERNO in a temperature range up to 650 °C or, respectively, up to 1200 °C. In the frame of an ESTEC funded study three types of microporous insulations - microfiber, microsphere and polyimide foam - have been analytically and experimentally investigated as candidates for the internal insulation of a MARS-lander in a carbon-dioxide atmosphere for temperatures ranging from - 110 °C to 50 °C. This paper compares the test results with analytical heat transfer calculations and describes methods to improve the thermal insulation performance.

At present, most of the trace contaminants in spacecraft are controlled by adsorption on activated charcoal filters which, after saturation, have to be exchanged. For longer duration mission, a regenerative trace contaminant control could practically eliminate the need for resupply of adsorbents. This study investigated the possibility of using hydrophobic zeolite molecular sieves for regenerative trace contaminant control. In small scale laboratory tests, different types of pelleted zeolite samples have been exposed to a model atmosphere containing representative trace contaminants. Co-adsorption capacities have been determined and the effect of parameters such as pellet size and shape, humidity level and flow rate has been studied. On the basis of this study, a regenerative trace contaminant adsorber applying two different molecular sieves is proposed.

Successful implementation of the MELISSA loop requires the optimum performance of each of its compartments. Preliminary studies on the behaviour of the photoheterotrophic compartment have been performed. The previously suggested strains have been tested for growth on the carbon and nitrogen sources expected to be components of the influent. The results indicate that of the organisms tested Rs.rubrum should become the organism of choice for the photoheterotrophic compartment while R.capsulatus is more appropriate for the photoautotrophic anaerobic compartment. Biomass analyses, determination of yields and growth rates have also been performed in the preliminary batch and continuous cultures.

This paper reports on the flight experiment ANITA (Analysing Interferometer for Ambient Air) and the development status of ANITA II. ANITA represents a precursor for ANITA II, a permanent continuous trace gas monitoring system on the International Space Station (ISS). For crew's safety the air analysers can detect and quantify quasi on-line and simultaneously 32 trace gases with ppm or sub-ppm detection limits. Thus, a crewed cabin air monitor is designed allowing the detection and monitoring of trace gas dynamics of a spacecraft atmosphere providing besides the continuous air monitoring activities, warning capability in case of malfunctions. ANITA will be accommodated in an Express Rack on US LAB Destiny. The transportation to ISS will be provided by Jules Verne, the first flight of the Automatic Transfer Vehicle (ATV) scheduled for May 2005. The more compact and improved measurement unit ANITA II is being designed for continuous air monitoring on ISS.

The ESTEC Large Space Simulator (LSS) is a facility which provides close simulation of in-orbit environmental conditions for spacecraft and payload testing. The LSS is equipped with a Motion System (MS), which allows spin rotation and attitude positioning of test objects. A part of the MS is the Slip-Ring Unit (SRU), located in the Spin box. The SRU makes it possible to transmit, among other, signals generated by temperature sensors fixed on the rotating test objects to a local Data Handling System. However, at present, only analog thermocouple channels are available for spacecraft temperature measurements. In order to extend the thermocouple channel capacity of the current SRU configuration and to make possible the acquisition unit has been conceived. Besides the multifunction feature, a particular effort has been made to achieve optimal measurement accuracy vs sensor type and to pursue the use of non-space qualified components.

Since 1985 in a step by step approach an advanced air revitalisation system has been developed for a crewed spacecraft. The metabolically produced carbon dioxide is concentrated through a solid amine water steam desorp-tion system and reduced to water and methane in a so-called Sabatier reactor. The water is currently fed into a fixed alkaline electrolyser to reclaim the oxygen for the crew. However, also water from other sources may be used. The hydrogen is recycled into the Sabatier reactor. The present system handles methane as a waste product closing so far the oxygen loop only. The system has been already successfully demonstrated in a laboratory scale configuration for a crew of three persons in 1996/1997. This paper discusses the results of the current development phase in which the system is reconfigured to fit into an International Space Station payload rack (ISPR). For this purpose the complete system design has been reviewed and upgraded where necessary.