Lifetime and Reentry Survivability Estimation for Orbiting Objects

The increase of space debris has raised concern among scientists and researchers globally. They are mostly found in the Low Earth Orbit (LEO). Due to their high orbital velocity, any collision with other space objects may result in a disaster as well as produce other debris. To predict the orbital information regarding the velocity and position of an object, different techniques such as semi-analytic, general and special perturbation have been employed by various space agencies.

These orbiting objects eventually reenter the Earth’s atmosphere because lifetime of the orbiting objects in the LEO is limited due to perturbations such as atmospheric drag. In this regard, reentry analysis codes have been developed to verify the conformability of the space debris and satellites to the set mitigation standards. These codes can be grouped as spacecraft-oriented code like Object Reentry Survival Analysis Tool (ORSAT) or object-oriented code like Spacecraft Atmospheric Reentry and Aerothermal Breakup (SCARAB). However, most of the codes are not open to the public. Although there are a few open codes such as Debris Assessment Software (DAS) and Debris Risk Assessment and Mitigation Analysis (DRAMA), they have some limitations compared to the ORSAT and SCARAB, implying a self-development is required.

Since an increase in the number of space debris poses a continual threat to the space assets and the Earth, it is critical to collect their data and prepare for the risk. Seong-Hyeon Park and Gisu Park at Korea Advanced Institute of Science and Technology in collaboration with Hae-Dong Kim at Korea Aerospace Research Institute developed an integrated system which has a reasonable level of computational power as well as accuracy for the orbit, orbital lifetime and reentry survivability estimation modules of the orbital objects. They compared each module of the integrated system with the results of the existing codes for the same initial conditions. They utilized Science and Technology Satellite-3 (STSAT-3) as the test model for both the reentry survivability and orbital lifetime prediction. Furthermore, the true anomaly effects and its sensitivity were investigated using the Monte Carlo simulation with the reentry initial conditions as the elements at the end of the orbital lifetime. The authors observed that the same number of surviving parts of STSAT-3 irrespective of the difference in the true anomaly because the near-Earth satellites with small eccentricity reach a circular orbit at the end of it’s lifetime due to its energy loss. However, elliptical orbits exhibited a significance in the survivability. Their work is published in the journal, Advances in Space Research.

The study is the first to successfully develop an integrated system within a single manuscript for the orbit, orbital lifetime and reentry survivability estimation of the orbiting objects. According to the authors, true anomaly effect is very important for survivability and reentry trajectory. The agreement between the modules and the existing codes confirmed the effectiveness of the developed integrated system. The authors hoped to contribute to the development of the national Space Situational Awareness (SSA) system.