Hypervelocity impact protection by a nominal two-plate aluminum spacecraft shield against milli- and centimeter-sized space debris

Hypervelocity collisions with space debris (SD, natural meteoroids and man-made artifacts) can significantly affect the performance of spacecraft. Here, I use an adaptivemesh Eulerian hydrodynamic code, Mie-Grüneisen solid-mechanics, and a simple material-failure model, running on a modern PC, to analyze the protection afforded by a nominal two-plate aluminum shield to hypervelocity collisions with millimeterand centimeter-sized aluminum and iron-nickel spheres, considered as SD proxies. The results indicate that such a shield would stop a 1-mm iron-nickel impactor at 9 km/s (the nominal mean speed of SD), and would stop a 1-mm aluminum impactor at 20 km/s. The shield would fail to stop a 1-cm aluminum impactor at 9 km/s, and 1-mm, and 1-cm, iron-nickel impactors at 20 km/s. These results variously validate, and characterize some limits of applicability, of the ballistic limit equations (BLEs) that are commonly used in spacecraft shield design and spacecraft mission planning.