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The European Space Agency ESA is preparing a mission to planet Mercury called BepiColombo in cooperation with ISAS, the Japanese space agency. Advanced thermal control materials and components are under development to allow the performance of the mission. The present paper gives an overview of the BepiColombo thermal control design and give emphasis to the continued effort in the development of a Solar Reflector Coating (SRC), an Optical Solar Reflector (OSR) and an Infra-Red Rejection Device (IRRD). Key issue in the development and validation of the components and related technologies is the long-term stability under the high temperature and high intensity radiation environment in the vicinity of Mercury. Therefore thermal and radiation endurance testing plays a major role. Candidate materials have been selected and the component design been defined. Development tests will establish mechanical, thermal and optical properties for the initial and end of life conditions.

For all future space transportation systems the capability for multiple use plays a major role. This fact comprises ascent, on-orbit and re-entry, maintenance and inspection on ground for all major components and subsystems. Beginning with HERMES Europe made great efforts in the re-entry technology development also. This affects e.g. guidance and navigation, aero-thermodynamic and Thermal Protection Systems (TPS). The US Advanced Flexible Reusable Insulation (AFRSI) as TPS was developed for the Space Shuttle and successfully flown since the beginning of its missions. In Europe, there were similar developments performed within the HERMES program. Depending on the temperature levels on the vehicle and the aero-dynamical or mechanical loads different TPS are used.

The outermost fabric of an astronauts space suit is directly exposed to the various space environmental hazards and therefore has to withstand the various loads arising during EVA operation. In a previous study phase the Outer Fabric for a European Space Suit (OFFES) has been developed using advanced technology and special surface protection components. Different design versions have been manufactured - using 3-D weaving as well as 3-D knitting technology - and were subjected to a test campaign covering the investigation of mechanical/tribological, chemical, thermooptical and micrometeorite and debris (M/D) protection properties of the material. The current phase is concerned with the further development of the fabric for its application on a space suit. For this purpose an arm segment of a thermal and micrometeorite protection garment (TMP) has been manufactured using a further improved version of the OFFES fabrics.

With the successful retrieval of EURECA, the EUROPEAN RETRIEVABLE CARRIER, again a long term orbit satellite (11 month in space) is available for the space material community to investigate the influence of low earth orbit environment on materials which stayed in orbit for a prolonged time. EURECA, designed, manufactured and launched to carry out numerous experiments in the fields of fluid- and solar physics, materials science, biology and astronomy under orbital conditions, in parallel presents a huge material expositon experiment in itself, providing detailed insight into the possible orbital degradation mechanisms due to the synergistic effects of atomic oxygen, UV radiation, thermal cycling, high vacuum and micrometeorite/debris impacts. In order to exploit the valuable information, an integrated ESTEC/ERNO team has been established to perform a detailed investigation of the EURECA surface and - as far as accessible -internal structural parts and experiments.

During Extravehicular Activities (EVA) an astronaut has to be protected against various external factors ranging from mechanical hazards to solar radiation and micrometeoroids. An important element in this external protection is the outermost fabric layer. It has to ensure the mechanical protection of the pressure retention bladder and at the same time - by its thermooptical properties - plays an important role in the thermal control of the space suit. New weaving and knitting technologies enable the fabrication of so-called 3-D fabrics with interconnected layers and local variation of properties in one manufacturing step. By this a tailored design of protection properties is possible. A study has been performed to define concepts adapted for use on a European Space Suit. Different fabric samples were manufactured and tested, amongst others, for strength, flexibility, puncture and wear resistance, UV stability, flammability, out/offgassing and micrometeoroid protection effctiveness.