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A Heat Switch has been developed, namely a device able to autonomously regulate its own thermal conductance in function of the equipment dissipation and environmental heat sink conditions. It is based on a Loop Heat Pipe (LHP) technology, with a passive bypass valve which diverts the flow to the Compensation Chamber when needed for regulation purposes. The target application is the potential use on a Mars Rover thermal control system. The paper recalls the Heat Switch design, and reports the results of an extensive test campaign on the ground demonstrator. The performance of the device was found extremely satisfying, and often exceeded the system requirements.

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.

The MELISSA (Microbial Ecological LIfe Support System Alternative) project has been set up to be a model for the studies on ecological life support systems for long term space missions. The compartmentalisation of the loop, the choice of the micro-organisms and the axenic conditions have been selected in order to simplify the behaviour of this artificial ecosystem and allow a deterministic and engineering approach. In this framework the MELISSA project has now been running since beginning 1989. In this paper we present the general approach of the study, the scientific results obtained on each independent compartment (mass balance, growth kinetics, limitations, compound conversions,..), the tests of toxicity already performed between some compartments and their effect on the growth kinetics. The technical results on instrumentation and control aspects, and the current status of the ESA/ESTEC hardware are also reviewed.

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.

Final preparation and configuration of the Columbus module at the Kennedy Space Center (KSC) required the performance of system level tests with the Active Thermal Control System (ATCS). These tests represented the very last system level activities having been concluded on the Columbus module before handover to NASA for space shuttle integration. Those very last tests, performed with the ATCS comprised the final ATCS Leakage Test, the final calibration and adjustment of the Water Flow Selection Valves (WFSV) and Water On/Off Valves (WOOV) as well as a sophisticated ATCS Residual Air Removal test. The above listed tests have been successfully performed and test data evaluated for verification closeout as well as input delivery for operational Flight Rules and Procedures. Some of the above mentioned tests have been performed the first time hence, a succeeding lessons learned collection followed in order to improve the perspectives of future tests.