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In a harmonized ESA/NIVR project the performance of membrane gas absorption for the simultaneous removal of carbon dioxide and moisture has been determined experimentally at carbon dioxide and humidity concentration levels representative for spacecraft conditions. Performance data at several experimental conditions have been collected. Removal of moisture can be controlled by the temperature of the absorption liquid. Removal of carbon dioxide is slightly affected by the temperature of the absorption liquid. Based on these measurements a conceptual design for a carbon dioxide and humidity control system for the Crew Transport Vehicle (CTV) is made. For the regeneration step in this design a number of assumptions have been made. The multifunctionality of membrane gas absorption makes it possible to combine a number of functions in one compact system.

Methane-filled heat pipes have been developed and qualified for the SCIAMACHY thermal bus assembly. The heat pipes provide an efficient heat transfer in the temperature range 100-160 K. Extensive qualification testing has been performed. The thermal bus assembly is part of the Thermal Bus Unit (TBU) of the SCIAMACHY Radiant Cooler.

An advanced trace gas monitoring system for long duration manned space missions - such as the International Space Station - is discussed. The system proposed is a combination of a Fourier-Transform Infrared Spectrometer (FTIR) and a distributed ‘Smart Gas Sensor system (SGS). In a running multi-phase programme [1,2] the FTIR technology, applying novel analysis methods, has been demonstrated to handle multi-component gas measurements, including identification and quantification of 20 important trace gases in a mixture. In the current phase 3, initiated end of 1997, a fully operational FTIR technology demonstration model will be manufactured and tested. The SGS consists of an array of twenty electrically conductive polymer sensors supplemented with an array of quartz crystal microbalance sensors. The technology has been tested on the Russian MIR space station and is currently miniaturized into a second-generation flight model.

The Automated Transfer Vehicle (ATV) is a European Space Agency autonomous, expendable logistic transportation system for Low Earth Orbit. The ATV will be launched by Ariane 5 and its mission is to contribute to the logistic servicing of the International Space Station: via the delivery of a cargo (crew items, scientific experiments, spare parts..) as well as of fluids such as propellant, water and compressed air via the provision of an extra service consisting of retrieving the station wastes when departing (replacing the upcoming cargo) and getting rid of them through the final destructive atmospheric re-entry of the ATV itself via the contribution to the orbit control of ISS by providing a reboost and attitude control capability to the ISS. The ATV consists of a Spacecraft and an Integrated Cargo Carrier. The Spacecraft includes all subsystems necessary for the automated flight to the ISS and for the reboost, including the propellant tanks and the thrusters.

After several years of development the first European Automated Transfer Vehicle (ATV) developed by ESA called Jules Verne completed successfully its seven-month ISS logistics mission. Launched the 9 March 2008 on an Ariane 5 launcher, the ATV performed the 3 April 2008 its rendezvous and docking to the International Space Station to which it remained attached for five months. This paper presents in a first part the ATV thermal control architecture based on a innovative active thermal control design built around 40 Variable Conductance Heat Pipes (VCHP) controlling the heat rejection and in a second part the in-flight thermal control behavior of the ATV Jules Verne observed during the seven months mission in both free flight and attached to ISS phases.

Temperature and humidity control are vital functions of an environmental control and life support system in a manned spacecraft. A MCHX Technology Demonstrator has been developed using hollow fiber membranes to remove heat and water vapor from the cabin air. The functional principle of the MCHX is based on micro porous hydrophobic hollow fiber membranes. Heat and water vapor are transferred through the membrane to the cooling the water. The water vapor will condense at the cooling water side. The technique promises a good alternative for the conventional noisy and power-consuming rotary condensate separator. This paper describes the MCHX development work including the rational for its concept, the module design and its performance data as a result of numerical predictions and a test campaign. The MCHX performance requirements are linked to those of the Columbus Laboratory, the European contribution to the International Space Station (ISS).

The ESA Polar Platform, as part of the ESA Columbus Development Programme, is scheduled to be launched as single passenger by an Ariane 5 vehicle in mid 1998. The multimission platform is designed to accommodate a wide range of payload complements to be flown on a series of missions in order to satisfy the growing future earth observation needs in continuation of the current ERS programme. Multi-mission capability is achieved by design modularity wherever feasible and cost-effective. This paper describes the thermal control design of the Polar Platform which follows its modular configuration and which has to cope with a wide range of generic performance parameters, whilst being adaptable to provide optimised performance for specific missions. Special thermal control features are highlighted as the software and hardware controlled heater systems, thermal doublers using carbon / carbon material and the battery compartment heat pipe radiator.

For a planetary base, a reliable life support system including food and water supply, gas generation and waste management is a condition sine qua non. While for a short-term period the life support system may be an open loop, i.e. water, gases and food provided from the Earth, for long-term missions the system has to become more and more regenerative. Advanced life support systems with biological regenerative processes have been studied for many years and the processes within the different compartments are rather complete and known to a certain extent. The knowledge of the associated interfaces, the management of the input and output phases: liquid, solid, gas, between compartments, has been limited. Nowadays, it is well accepted that the management of these phases induces generic problems like capture, separation, transfer, mixing, and buffering. A first ESA study on these subjects started mid 2003.

If man leaves Earth for a long time to settlements on the Moon or Mars, he will be dependent of Closed Ecological Life Support Systems (CELSS) for the recycling of waste and the production of food. A large amount of the inedible plant material has to be pretreated and converted into a form which can be recycled. The main portion of this biomass is lignocellulosic material which cannot or only slightly be degraded by micro-organisms. White-rot fungi like Pleurotus spp. (oyster mushroom) or Lentinus edodes (shiitake or black Chinese mushroom) degrade these fibrous material more efficient than other micro-organisms and produce edible and also tasteful mushrooms which will increase the quality and nutritional value of the settlers diet. In the MELISSA (Micro-Ecological Life Support Alternative) project, a project under the management of ESA to study CELLS, it was observed that also human faeces contain a considerable amount of fibrous materials which pile in the loop.

Membrane gas absorption for the control of CO2 in manned spacecrafts is studied by Stork and TNO. Membrane Gas Absorption (MGA) is based on the combination of membrane separation and gas absorption. The cabin air of a spacecraft is fed along one side of a hydrophobic membrane. The air diffuses through the membrane and the CO2 is selectively absorbed by an absorption liquid. Experiments showed that the MGA system can not only be used for the removal of the carbon dioxide but also can be applied to control the relative humidity and temperature of the cabin atmosphere. Absorption of moisture and heat is achieved by cooling the absorption liquid below the dewpoint temperature of the gas stream. This paper deals with the design aspects of a MGA system for combined CO2, humidity and thermal control aboard the Crew Transfer Vehicle. Furthermore, design data are presented for a similar system aboard the International Space Station.

The Minus Eighty (Degrees Celsius) Laboratory Freezer for the International Space Station (MELFI) is one of the freezers developed by ESA on behalf of NASA. Peculiar requirements for that facility are the long-term storage at low temperature, the rapid freezing of specimen to the required temperature, the large cold volume (300 l) and the low power consumption. To verify those requirements before the manufacturing of the flight hardware, a dedicated test campaign was performed on a ground model. This paper will start with a system overview, showing the main features of MELFI. The test set-up as well as their results will be presented and discussed, with particular emphasis on the methods used to predict the on-orbit (0-gravity) behaviour, by avoiding the sample internal convection and dewar internal convection during the test execution.