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CryoSat is the first satellite of ESA's Living Planet Programme realised in the framework of the Earth Explorer Opportunity Missions. CryoSat is a radar altimeter mission dedicated to determine trends in the ice masses of the Earth. The overall spacecraft configuration was driven by the budget constraints applicable for the opportunity mission, the high inclination orbit with drifting orbit plane and the stringent stability requirements for the radar altimeter antennas. Innovative thermal design solutions were needed for the following items: The instrument antennas have to comply with very stringent pointing stability requirements. The star trackers need to be mounted at a thermally adverse position and still have to be maintained on low temperature levels.

Columbus is being built as the European contribution to the International Space Station (ISS) Program. The ECLS subsystem is developed by DaimlerChrysler Aerospace/Dornier under a contract from Alenia Aerospazio. This paper will survey the qualification test results of the Columbus cabin ventilation subjective test conduction up to February 2000.

An orbital flight test program for a fixed alkaline electrolyte (FAE) electrolyser stack is planned to be performed in September 2003 on board a Spacehab mission. The flight experiment is supposed to demonstrate the readiness of the FAE technology as one essential component to close the oxygen loop on board the ISS by means of an Air Revitalization System, ARES. The paper describes the design of the experiment, the current development status and the intended test program in space and shows its programmatic relation to ARES.

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.

In the range of the Columbus Orbital Facility (COL) program, the European contribution to the International Space Station (ISS), DASA Dornier developed and qualified four new supporting devices for the Environmental Control and Live Support System (ECLSS) as listed below: 1. The Vacuum & Venting Pressure Sensor (VVPS). Based on the Pirani principle, it utilizes the pressure dependence of the gas thermal conductivity. 2. The Humidity Sensor (HS) provides information for the Thermal & Humidity Control System (THC). It works according to the dew point principle, guaranteeing a long stability over at least 10 years. 3. The Air Flow Sensor (AFS), working according to the hot wire anemometer principle, is dedicated to identify low air flow conditions. 4. The Waste Gas Line Shut-Off Valve (WLSOV), a DC motor driven ball type vacuum valve, was adapted to the space station requirements (e.g. noise and micro-g).

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.

Metop (METeorological OPerational satellite) is a series of three satellites designed to monitor the climate and improve weather forecasting. This paper describes the thermal analysis, thermal testing performed, and relevant lessons learned. For the thermal analysis campaigns it focuses on: exchange and correlation of reduced thermal mathematical models established in various software formats sizes and content of the models, in particular automatic generation of reduced models from the detailed models uncertainties definitions of thermal interfaces The lessons learned from the thermal testing campaigns apply to: selection of test environment, using solar simulation and/or infra-red techniques selection of test cases based on thermal design driving parameters and/or test chamber capabilities adequate instrumentation (i.e. thermocouples, test heaters) for all critical components (un)expected events e.g.

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.

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.

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.

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.

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.

In 1995 the European Space Agency did award a C/D Contract for the design & development of an ECLS Subsystem for the Multi Purpose Logistics Module (MPLM) to Astrium’s ECLS ‘Center of Competence’ that built the ECLSS for Spacelab already. Actually first MPLM modules were successfully flown to the ISS with the Astrium built ECLSS qualified as ‘excellent’ by the crew having asked permission to sleep in there. In parallel the design and development of an ECLS for Europe’s Columbus module did commence and is actually close to completion. In view of the above a broad set of qualified and even space proven ECLS equipment is now ‘on-hands’ to thoroughly compose respectively derive the ECLS subsystems of future applications e.g. HabModule, CRV and Space Hotel at a limited delta design and validation effort thus fitting into the tighter financial budgets of the manned space programs to come.

NIRSpec is a near-infra-red spectrometer and one of the four instruments onboard the James Webb Space Telescope (JWST). The JWST observatory will be placed at the second Lagrange point (L2). The instrument will be operated at about 30 Kelvin. Temperature stability and controlled heat rejection to dedicated JWST radiators are important issues of the NIRSpec thermal design. Besides thermal insulation, the NIRSpec Optical Assembly Cover also has to provide light tightness and stray light suppression to prevent unwanted light entering the instrument. Air tightness is needed to allow a controlled purge gas flow for contamination prevention while allowing proper air venting during launch. Because of mass constraints a cover employing two-foil Kapton blankets supported by aluminum posts and a wire tent was chosen. Failure tolerance and cleanliness are other important design drivers. This paper describes the design solutions established to fulfil the contrary requirements

The Closed-Loop Air REvitalisation System ARES is a regenerative life support system for closed habitats. With regenerative processes the ARES covers the life support functions: 1. Removal of carbon dioxide from the spacecraft atmosphere via a regenerative adsorption/desorption process, 2. Supply of breathable oxygen via electrolysis of water, 3. Catalytic conversion of carbon dioxide with hydrogen to water and methane. ARES will be accommodated in a double ISPR Rack which will contain all main and support functions like power and data handling and process water management. It is foreseen to be installed onboard the International Space Station (ISS) in the Columbus Module in 2013. After an initial technology demonstration phase ARES shall continue to operate thus enhancing the capabilities of the ISS Life Support System as acknowledged by NASA [5]. Due to its regenerative processes ARES will allow a significant reduction of water upload to the ISS.

1 The Closed-Loop Air REvitalisation System ARES is a proof of technology Payload. The objective of ARES is to demonstrate with regenerative processes: the provision of the capability for carbon dioxide removal from the module atmosphere, the return supply of breathable oxygen within a closed-loop process, the conversion of the hydrogen, resulting from the oxygen generation via electrolysis, to water. The ARES Payload is foreseen to be installed - in 2012 - onboard the ISS in the Columbus Module. The operation of ARES - in a representative manned microgravity environment - will produce valuable operational data on a system which is based on technologies which are different from other air revitalization systems presently in use. The ARES Technology Demonstrator Payload development started in 2003 with a Phase B, see references [1], [2], [3] and [4]. ARES is presently in Phase C1 and a PDR is scheduled for the beginning of 2009.

The Herschel satellite is a space based telescope designed for the investigation of sub millimeter radiation from astronomical objects. The cryogenic system is an essential part of the telescope’s Extended Payload Module (EPLM). The cryogenic system has to provide an environment of sufficiently low temperatures to assure the proper functioning of the scientific payload. Main component of the cryogenic system is the cryostat, a huge vacuum vessel (see: Figure 1) with various cryogenic components inside. In order to qualify the components of the cryogenic system, multiple tests such as leak tests, thermal cycle tests, pressure cycle tests and vibration tests are performed. In this paper the test program for two cryo components, the rupture disc and a safety valve is discussed. The testing philosophy is presented and selected results of tests at ambient and low temperatures are shown.

The current ECLS baseline of the International Space Station ISS contains an open oxygen loop. Breathable oxygen, generated by electrolysis of water, is supplied to all habitable modules. The crew of max. 7 astronauts converts the oxygen into metabolic carbon dioxide, which needs to be removed from the ISS atmosphere. Adsorption of CO2 is achieved through molecular sieves, desorption of CO2 is conducted by evacuation into space. This open process needs approx. 1500 kg of water upload mass annually. More than 75 % of this upload mass can be saved, if the open oxygen loop will be closed. This paper outlines the closed loop air revitalization system of Astrium, ARES, which has been successfully tested in closed chamber tests. It demonstrates in detail the technical application of ARES on ISS and outlines the commercial benefits. The second part of the paper describes ARES for a Mars habitat with a closed oxygen and hydrogen loop.

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.

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.