In-space thermoelastic stability of starshade structures

We describe testing and analysis conducted to demonstrate in-space thermoelastic shape stability of starshade structures. Thermoelastic deformation testing was conducted on key starshade structural components. These components were constructed at relevant scales and at relevant fidelity to flight-like structures. Results from thermoelastic deformation testing were used to calibrate high-fidelity finite element structural analysis techniques; these finite element tools were then used to predict the in-space thermoelastic distortions of a 26 m-diameter starshade. The in-space temperatures for these structures were predicted using a separate radiative-thermal finite element simulations, and were meant to envelope temperatures that a starshade would experience during periods of telescope shading. The predicted in-plane thermoelastic deformations of this 26 m-diameter starshade were found to be sufficient to fit into an overall error budget to enable instrument contrast better than 1e-10.