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Herschel and Planck satellites have recently undergone the thermal vacuum and thermal balance (TVTB) test which was performed in the ESA-ESTEC Large Space Simulator for Herschel and in Centre Spatial de Liège (CSL) for Planck. One of the specific targets of the Herschel test was the verification of the thermal stability of two HIFI units (required to be better than 3.10−4 °C/s) and of the Star Tracker mounting plate (required to be better than 2.5.10−3 °C/s), with particular attention on the performance of the relevant feedback control loops. Control system design and model predictions are presented and compared against the test results. Further discussion on the requirement verification is provided.

The MPLM (Mini Pressurized Logistic Module) is one of the Elements constituting the ISSA (International Space Station Alpha). With respect to the other Elements, the MPLM is not permanently attached to the ISSA, but it is transported by the Orbiter several times from/to the Earth, since its primary use is to resupply and return cargos. The MPLM capability to support the logistic flights is guaranteed during several mission phases (ground, Orbiter transportation, on-orbit docked to the Station). Since the installed cargo can be passive or active, the required MPLM functions are based on the actual flight. This paper presents an overview of the activities performed in Alenia Spazio to identify the criticality and peculiarity of the MPLM mission scenarios from the thermal point of view. The best technical solutions, foreseen up to now, have been implemented in the design to guarantee the reliability requested by such an important and unique Space Station Element.

The Automated Transfer Vehicle (ATV) is one of the major European contributions to the International Space Station Alpha (ISSA). The ATV will be launched with ARIANE 5 and will be used for servicing of ISSA with pressurized and unpressurized cargo as well as for ISSA refuelling and reboost. The ATV consists of a Core Module and a Cargo Module. The Core Module includes all major subsystems including the propellant tanks required for the automated flight to ISSA. Eight 400 N thrusters are accommodated on the bottom platform for orbit transfer and reboost of ISSA. Twenty 200 N thrusters, accommodated on the cylindrical shell of the core module, are provided for attitude control. The thermal control of the ATV consists of a passive subsystem supported by an electrical heater system. The waste heat of most of the avionics equipment is collected and transferred via conduction through the box baseplate to the avionics platform and further on to the cylindrical shell.

ESA has planned two important missions for performing astronomical investigations in the infrared and sub-millimetre wavelength range: Herschel satellite has an observatory type mission and is the fourth cornerstone mission (CS4) of the “Horizon 2000” programme. It will carry three instruments (HIFI, SPIRE, and PACS) for high and medium resolution spectroscopy, imaging and photometry over the sub-millimetre and far-infrared range. A 3.5 m telescope will focus the incoming radiation on the Focal Plane Units of these instruments. Planck satellite has a survey type mission and is the third Medium mission (M3) of the “Horizon 2000” programme. It will provide a definitive high-angular resolution map of the cosmic microwave background anisotropies over at least 95% of the sky and over a wide frequency range. A 1.5 m telescope will focus the incoming radiation on the focal plane shared by the two instruments (LFI and HFI).