Kilometer-Scale Parabolic Reflector for a Radio Telescope in a Lunar Crater

We present a structural architecture for a parabolic reflector for a conceptual radio telescope on the Moon. We study a point design with a structural diameter of 1.3 kilometer and a reflector diameter of 350 meter. The structural architecture is based on the tension truss concept: a network of tensioned cables with pre-determined length to provide shape and stability, with a compliant metallic mesh stretched between the cables for radio reflectivity. The reflector hangs from the rim of the crater, and the cables are tensioned through self-weight. This method leads to a lightweight design. We present preliminary structural analyses showing acceptable surface accuracy given various error sources. We discuss two methods for packaging the reflector. The deployment is envisioned to be carried out by robotic means.