Orbit, orbital lifetime, and reentry survivability estimation for orbiting objects

In this work, an integrated system for the orbit, orbital lifetime, and reentry survivability estimation modules of orbiting objects has been proposed and developed. Each module of the system was compared and validated with results from the well-known existing codes. One practical test model was considered for the orbital lifetime and the reentry survivability. The model was Science and Technology Satellite-3 (STSAT-3). Recently, the STSAT-3 was almost to collide with a space debris. This issue brought a serious alert to the public in Korea regarding collision risks of the orbiting object and a possibility of a consequent threat to the survivability when the object survives and impacts human. For this case study, it was assumed that the satellite consists of 12 parts having different shapes, materials, and sizes. The estimations showed that the calculated orbital lifetime was about 32 years and 7 out of 12 parts survived during the reentry. The effect of true anomaly for the orbiting object on the reentry survivability has been considered in the calculation. The results showed that there is no strong effect on the survivability for different true anomalies in a circular orbit. For an elliptic orbit which is regarded as an extreme case for the near-Earth orbiting object, however, a large difference was observed. Possible reasons are discussed. This work is intended to contribute to the part of the development of the national Space Situational Awareness (SSA) system, for the first time showing an overall procedure for the method of the integrated system.