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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.

The first use of the Polar Platform (PPF) is for the Envisat/PPF mission. The Envisat/PPF spacecraft has a launch mass of 8.5 tons and external dimensions of 10.0 metres x 2.8 metres x 2.1 metres. Due to it's large size it was necessary to perform the thermal balance and thermal vacuum testing in two modules. The first test was for the Service Module (SM) and the second for the Payload Module (PLM). This paper discusses the thermal balance testing and subsequent correlation of the Polar Platform Service Module thermal mathematical model.

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.

The European Polar Platform is a remote sensing satellite with the primary objective in the ENVISAT-1 Payload configuration to monitor and study the earth and its environment. The platform thermal design is passive, assisted by heaters. The ENVISAT-1 Payload consists of several instruments which are responsible for their own thermal control and are required to be thermally decoupled from the platform. ENVISAT-1 platform thermal analyses are performed at various levels: system module instrument unit/subassembly The paper describes a typical system thermal analysis campaign in terms of: geometrical and mathematical models used configurations (e.g. stowed, deployed appendages) and attitudes (e.g. nominal, safe mode) analysed analysis content and results Specific aspects of the system analyses are discussed e.g. complexity of system model which is an assembly of several models established by different companies.

The European Polar Platform is a remote sensing satellite with the primary objective, in the ENVISAT-1 P/L configuration, to monitor and study the earth and its environment. The platform thermal design is passive assisted by heaters. Externally mounted P/Ls are responsible for their-own thermal control and are required to be thermally decoupled from the platform. The P/L thermal design is largely dependent on their detectors required temperature and stability. A wide range of design solutions is found: Stirling cycle coolers, Peltier elements, passive radiant coolers, heat pipe radiators. This paper describes the overall thermal design of the platform and the P/Ls, the principles of the selected ENVISAT-1 P/L accommodation, the relevant P/L to platform I/F design solutions and outlines the platform and P/Ls thermal verification logic.

The Environmental Control System (ECS) of two of the three configurations of the Columbus Programme, namely the Columbus Attached Laboratory (APM) and the Free Flying Laboratory (MTFF) provides a micro environment in space to support safe and comfortable working conditions for the crew and necessary resources to perform experimental activities. Recent developments in the international in-orbit infrastructure, i.e. the Space Station Freedom (SSF) with the APM as European contribution and the European elements MTFF with HERMES and the ARIANE-5 launcher are rapidly converging towards matured engineering and programmatic goals. The restructuring activities (SSF), detailed reconsideration of key requirements (MTFF) and cost saving options task force (APM) are examples which have already, or will considerably impact the ECS of the involved Columbus flight configurations.