Stable Satellite Structures   XMM telescope tube with thermal insulation blankets.     In the recent past ESA successfully launched some large science satellites with composite primary structures (e.g. XMM and Envisat). The design drivers for such structures are mass, stiffness and stability. For XMM, the structure must allow the spacecraft to serve as an optical bench for a telescope and therefore must provide the necessary thermo-elastic stability in orbit. In the case of XMM, the telescope tube has a length of 6.8m. To achieve the required stability ultra-high-modulus M60J carbon-fibre with a 954-3 cyanate ester matrix and a strongly directional lay-up was used.         Last update: 31 July 2007 Related articles  •  Composite design and analysis tools (http://www.esa.int/TEC/Structures/SEM8VDWUP4F_0.html)  •  Composite Joints and Inserts (http://www.esa.int/TEC/Structures/SEM95EWUP4F_0.html)  •  Launcher Structures (http://www.esa.int/TEC/Structures/SEMPQDWUP4F_0.html)  •  Satellite Structures (http://www.esa.int/TEC/Structures/SEMKYEWUP4F_0.html)  •  Composite Technology Studies (http://www.esa.int/TEC/Structures/SEMSMFWUP4F_0.html)