SiC-foamed mirror for telescope operating in space or on ground

By combining the excellent intrinsic thermo-mechanical properties of the SiC (silicon carbide) with a structural design based on a sandwich structure composed of two SiC face sheets CVD (chemical vapor deposition) deposited on a foam core of the same material, it is possible to manufacture very light and stiff primary mirrors for telescopes to be operated in space or on ground. The paper presents an analysis of the mechanical properties of this structure, it proposes a preliminary design of a segmented mirror and support pattern for space or for on ground telescopes, and it points out the important saving in weight which is possible with respect to other approaches used to manufacture lightweight mirrors.