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This paper describes the Thermal Balance test that has been performed on the PAMELA telescope Pressurized Container (PC) to verify the performance of the PC Thermal Control System (TCS). The PC will be attached outside the Russian satellite RESOURS DK to be flown in2004 The thermal control system of the PAMELA PC is based on a mechanical pumped loop fed with Isooctane as working fluid. The test has been performed with PAMELA Structural Thermal Model (STM) inside the PC to have representative interfaces for the thermal control system. Simulation of close-to-real flight environmental heat loads have been accomplished in a vacuum chamber by means of a complex system of IR lamps suitably oriented toward the PC and mechanically mounted on a tubular structure outside the PC. Overall test results have been excellent; PAMELA thermal control system thermal/fluidic requested performance have been verified. PAMELA telescope thermal interfaces have been confirmed as well.

Being in charge of the thermal design and analysis for three external payloads that will fly on the ISS (EuTEF, EUROPA and LOBSTER) we highlight in this paper the commonality among them: they are attached to standard adapter plates and have standard resources in terms of power and mass allocation. These payloads, despite these commonalities have specific features due to the different scientific targets, are in different development phases and occupy various locations outside the International Space Station (ISS). Even if thermal requirements are not substantially different the different locations imply different environment and therefore different thermal control solution. Also analytical models of the ISS are different due to ISS development phase and details in proximity of payload location. The paper goes through common thermal design choices and specific solutions adapted to the specific needs of each of them.

This paper describes the thermal modeling and analyses performed on the LISA Technology Package (LTP), with special attention to the frequency domain requirements on the sensitive instrumentation. The new approach is presented, and the modeling and analysis phases are described in detail. Results about LTP thermal stability in the frequency domain are shown, and obtained though two alternate approaches. The first one consists in the study of the transient response of the system to a periodic input with a frequency equal to the minimum frequency of interest, using the well known low-pass filtering properties of the thermal systems. The second is based on the generation of a time dependent input, starting from its Power Spectral Density definition: this input is used to run a transient thermal analysis and finally transform its results into the frequency domain. Thermal stability assessment studies have been performed also at spacecraft level and are well described in [ref. 3].