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Flexible thermal links are necessary to couple thermally but flexibly instrument sensors to their heat sink. Three promising flexible thermal link design concepts are described and investigated, the braided solid conductor made of metallic foils, the spring-shaped axial grooved heat pipe and the carbon fibre thermal link. The design principles of those concepts are presented. Advantages, drawbacks and critical points are analyzed and typical performance data are reported. This work includes also results from mechanical and thermal tests performed on various flexible thermal link samples. The investigations reveal, that braided metallic conductors can cover the widest range of applications. However, for a certain range of applications, the spring-shaped heat pipe and the carbon fibre link are valid alternatives with significant improvement of the thermal conductance associated with lower mass and similar mechanical performance.

GOCE (the Gravity Field and Steady State Ocean Circulation Explorer) is the first Earth Explorer Core Mission of the Earth Observation Envelope Program of the European Space Agency (ESA). The Satellite is planned to be launched in June 2008 on a Rockot launcher into a near-circular sun-synchronous orbit for Earth's gravity field measurements. The objective of the mission is to produce high-accuracy, high-resolution, global measurements of the Earth's gravity by satellite, leading to improved gravity field and geoid models for use in a wide range of applications (geodesy, solid-Earth physics, oceanography, climate, ice topography). In particular, the goal is to produce a map of the gravity anomaly field with an accuracy better than 1mGal (1 mGal=10-5 m s-2), and of the geoid height with accuracy better than 1 cm, all over the Earth's surface with a resolution at sea level of at least 100 km.

MetOp is a series of three meteorology and climate monitoring satellites, which will be launched using the Russian Soyuz-Fregat vehicle over a period of 14 years starting in 2005. MetOp will form part of the American ‘Polar Orbiting Environmental Satellites’ (POES) programme, a further step in European/American collaboration in space. The MetOp satellites will fly in a sun-synchronous polar orbit at an altitude of between 800 and 850km, with a repeat cycle of 29 days. The satellite is based on the successful Spot platform, which has carried a number of European earth observation satellites over the last 15 years, and consists of two parts: 1. The Payload Module (or PLM) which carries twelve instruments, provided by the European Space Agency (ESA), the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), the American National Oceanic and Atmospheric Administration (NOAA) and the French space agency, CNES. 2.