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Today, in several industrial fields, the integration of functions is a key technology to enhance the efficiency of components in terms of performance to mass/volume/cost/ratio. Concerning the space industry, in the last few years the trend in spacecraft design has been towards smaller, light-weight and higher performance satellites with sophisticated payloads and instrumentation. Increasing power density figures are the common feature of such systems, constituting a challenging task for the Thermal Control System. The traditional mechanical and thermal design concepts are evidencing their limits with reference to such an emerging scenario.

The INTEGRAL (International Gamma Ray Astrophysics Laboratory) program is an ESA observatory scientific satellite to be used for gamma ray astronomy, It was successfully launched on the 17th of October 2002 with a Proton launcher from Baikonour Cosmodrome and after a dedicated Commissioning Phase it was ready to start its scientific mission. After 2 years the first lifetime goal (nominal lifetime) was reached and it entered the extended lifetime (3 additional years) Alenia Spazio, who had the role of Prime Contractor, was fully responsible of the Thermal Control of the satellite. During 2.5 years the satellite was carefully monitored and the thermal control design mounted on it has been capable to meet all the thermal requirements, providing the optimal thermal environment.

SAX (Satellite Astronomia Raggi-X) is the Italian Satellite devoted to study in the X-Ray wavelengths. X-rays in the range 300 keV to 0.1 keV will be observed over a wide field by means of 8 Scientific Instruments. The SAX orbit is circular with an altitude of 600 km and a maximum inclination of 5°. A life of 26 months is foreseen. The Thermal Control Design, which will make use of Passive Thermal Control elements ( Heaters, MLI, Paints), shall guarantee the best thermal environment for the Scientific Instruments. This includes not only control of the temperature level, but also of the magnitude of temperature gradients between different sides of the same Instrument. Naturally, the thermal control features must not obstruct the Instrument Field of View (FoV). The TCS shall also control the temperature of all the other Satellite equipment such as the Battery, Propulsion (Hydrazine) elements (Tank, Thrusters and Lines), and AOCS sensors.

EURECA (EUropean REtrievable CArrier) has been designed as a multi-purpose carrier with a dedicated payload for different experiments (microgravity, astronomy, earth observation, solar physics and technology mission application) to be used during several missions. The EURECA Thermal Control design is subdivided in an “active” thermal control and a “passive” thermal control. The active thermal control is based on a Freon Fluid Loop composed of By-Pass valve, Cold Plates, Radiators and its scope is to guarantee a limited temperature range excursion for some P/L equipments and particular spacecraft units (e.g. Batteries). The passive thermal control composed of MLI blankets and MLI radiators, TCU (Thermal Control Unit), heaters, paints and tapes is instead devoted to maintain the temperature level of the overall carrier components within an acceptable value. Special attention was dedicated to the Hydrazine lines, tanks and thrusters to fulfil the stringent STS safety requirements.