Pyblossum: An Open-Source Python Repository for Assessing the Ballistic Limit of Spacecraft Structures Under Space Debris Impact

Abstract Introduction Ballistic limit equations (BLEs) are used to predict the performance of a spacecraft shield or component when impacted by a space debris particle. Together with impact flux estimates, BLEs are inputs to mission risk assessments which estimate the probability of mission failure arising from operating spacecraft in a congested debris environment. For such risk assessments a BLE must be assigned to every external structure and critical component onboard a spacecraft, including dedicated shielding, thermal blankets, batteries, propellent tanks, cable harnesses, etc. NASA’s handbook on micrometeoroid and orbital debris (MMOD) protection [1] provided an overview of many BLEs, together with an accompanying software package [2] and user manual that includes validation information for many of the equations [3]. However, the software package in [2] had limited distribution, was closed-source, and was never updated. Although most BLEs are straight-forward to implement in risk assessment software packages, some include recursive constants that require optimization during the calculation, e.g., the Reimerdes-modified Whipple shield BLE [4], etc. In addition, several original BLE publications include typos and mistakes, e.g., [3][4], complicating their replication, see e.g., [5].