Forensic Analysis of On-Orbit Debris Generation Events

On-orbit fragmentation events, both collisions and explosions, continue to occur in spite of efforts to reduce their frequency through application of debris mitigation measures. Frequently the cause of these debris-producing events is not immediately known and there may be very little data available with which to determine a cause. Over the last several years The Aerospace Corporation has developed several techniques to characterize debris objects from dozens of historical fragmentation events. It has also improved its fragmentation modelling capabilities. Through these improvements it has become possible to estimate both the characteristics of the individual fragments from a debris producing event on orbit as well as the characteristics of the fragmentation event itself. This paper will examine the approaches that have been developed to characterize the fragments and the debrisproducing events. Estimates of the velocity imparted by the debris generation event (spreading velocity), fragment area-to-mass ratios and approximate mass can be made to characterize individual fragments. The results from these individual analyses can be aggregated to produce spreading speed, area-to-mass ratio (AMR), and mass distributions which can reveal key characteristics of the debris generating event, such as event time and location, and energy involved.