Dynamic and optical characterization of dusty plasmas for use as solar sails

Solar sails presently have mass loadings of 5 gm/m(2) that, when including the support structure and payload. could easily average to >10 gm/m2. For reasonably sized spacecraft. the critical parameter is the total mass per total area, which when combined with the reflectivity, yield the true acceleration. We propose that dusty plasmas trapped in a "Mini-Magnetosphere" (Winglee. 2000) can produce a solar sail with a total mass loading <0.01 gm/m(2), and reflectivities of similar to 1%. This configuration provides an acceleration equivalent to a standard sail of 95% reflectivity with <1gm/m(2). HoN ever, the physics of dusty plasma sails is not mature and several important questions need to be resolved before a large scale effort is warranted. Foremost among these questions are, hat is the largest force a dusty plasma can sustain before it demagnetizes and separates from the binding magnetic field: hat are the charging properties of dust under solar UV conditions, what is the light scattering cross section for the dust; what is the optimum dust grain size for magnetization and scattering: and, what are the optimum dust grain materials? We outline what we know about dusty plasmas, and what we are hoping to learn from two existing dusty plasma experiments at the National Space Science and Technology Center (NSSTC) and Auburn University.