Spacecraft Geometry Effects on Kinetic Impactor Missions

Abstract The DART (Double Asteroid Redirection Test) mission will impact a spacecraft on the secondary (Dimorphos) of binary asteroid system Didymos in 2022 September, with goal altering orbital period Dimorphos about sufficiently to be observed from ground-based observations. Numerical modeling is crucial component understanding outcome experiment, and while many have investigated effects target properties, such as material strength porosity (which remain unknown), an often overlooked factor importance accurately representing itself models. Most date has considered simple impactor geometries solid uniform sphere, but reality complex shape full different components, open spaces, thin walled structures. At minimum, representation underestimates surface area impact: for small body (approximately 160 m diameter), difference between spanning 20 (including solar arrays) impacting sub-1 idealized may important. In this paper, we compare models high-fidelity based CAD geometry various simplified impactors, order assess potential effect. We find that simplest (such sphere) real measurable, interesting dependence properties itself.