Optimizing electrostatic radiation shielding for manned space vehicles

Abstract

The shield has three concentric grids having a net charge of zero. The voltage across the outer pair is chosen to repel electrons; and that across the inner pair is chosen to repel nucleons. The negative grid is coated to absorb ultraviolet light to prevent photoemission, and secondary emission is minimized by a grid/thin foil combination. Voltage is maximized and mass minimized by setting the ratio of the negative to the inner positive electrode radii to ≥ 2. The outer grid pair forms a space truss with rigid geodesic grid, from which catenary tensile members are suspended. For docking there is passage directly through the sparse gridwork of larger structures, or through a charge shifting vestibule on smaller. While efficiency increases indefinitely with size, favorable sizes for given voltages are indicated. Large modular habitats and small powered transport vehicles are protected with efficiencies several orders of magnitude over mass shielding against charged particle cosmic radiation.