A novel size distribution model for debris generated by in-orbit collisions

• A novel characteristic length cumulative distribution model is presented. • The model considers the effect of different collision parameters. • The paper includes a sensitivity analysis and a tuning process for model coefficients. • A transition region is proposed between sub-catastrophic and catastrophic events. • Obtained distributions are in line with both observations and experimental data. In-orbit fragmentation events can generate debris clouds of thousands of objects, that may strongly affect the debris environment and the management of orbital assets. Ground observations are employed to catalogue detectable objects; however, the observation and identification of the generated debris may require months or even years. Simplified models, such as the NASA Standard Breakup Model, can assess the effects of in-space breakup and promptly provide fragments properties distributions; nevertheless, literature data suggests that they might present some limitations when modern satellite designs or complex impact geometries are involved. In this context, a novel Italian Breakup Model is under development, to provide a more reliable description of the fragmentation events; in particular, a piecewise analytic size distribution equation has been conceived and tuned with both observation data and ground experiments. The model description and its calibration and validation process are reported in this paper; the obtained results show that it accurately captures the trends in experimental and observational data with greater accuracy compared to other existing formulations.