Modeling of space debris reentry survivability and comparison of analytical methods

Prediction of reentry survivability of objects during orbital decay is necessary because of adoption of guidelines to reduce orbital lifetimes of non-operational spacecraft and upper stages. The purpose of this paper is to present results from the NASA Object Reentry Survival Analysis Tool (ORSAT) for several reentry bodies and benchmark/parametric analyses of hollow spheres. The ORSAT methodology is summarized describing operation of six general models of the code: trajectory, atmosphere, aerodynamics, aeroheating, thermal, and debris area/ground impact risk. Spinning and nonspinning spheres are evaluated, as well as cylinders, boxes, and flat plates for various tumbling modes. The demise altitude is predicted when the object integrated heat load becomes greater than the material heat of ablation. Results are presented to assess effects of drag coefficient, ballistic coefficient, atmosphere model, wall thickness, diameter, flight path angle, and material on object demise or survival. Results are also presented to determine demise or survival of various spacecraft, including the Delta second stage rocket fragments, Sandia barium fuel rod, and Japanese Advanced Earth Observing Satellite (ADEOS) components. Close agreement of ORSAT predictions is shown with Sandia fuel rod flight measurements and Delta second stage reconstructed trajectory predictions from Aerospace Corporation.