The key risk analysis technologies for the re-entry of space objects into Earth’s atmosphere are divided into four categories: cataloguing and databases of the re-entry of space objects, lifetime and re-entry trajectory predictions, break-up models after re-entry and multiple debris distribution predictions, and ground impact probability models. In this study, we focused on reentry prediction, including orbital lifetime assessments, for space situational awareness systems. Re-entry predictions are very difficult and are affected by various sources of uncertainty. In particular, during uncontrolled re-entry, large spacecraft may break into several pieces of debris, and the surviving fragments can be a significant hazard for persons and properties on the ground. In recent years, specific methods and procedures have been developed to provide clear information for predicting and analyzing the re-entry of space objects and for ground-risk assessments. Representative tools include object reentry survival analysis tool (ORSAT) and debris assessment software (DAS) developed by National Aeronautics and Space Administration (NASA), spacecraft atmospheric re-entry and aerothermal break-up (SCARAB) and debris risk assessment and mitigation analysis (DRAMA) developed by European Space Agency (ESA), and semi-analytic tool for end of life analysis (STELA) developed by Centre National d’Etudes Spatiales (CNES). In this study, various surveys of existing re-entry space objects are reviewed, and an efficient re-entry prediction technique is suggested based on STELA, the life-cycle analysis tool for satellites, and DRAMA, a re-entry analysis tool. To verify the proposed method, the re-entry of the Tiangong-1 Space Lab, which is expected to re-enter Earth’s atmosphere shortly, was simulated. Eventually, these results will provide a basis for space situational awareness risk analyses of the re-entry of space objects.

1. INTRODUCTION
 2. THE HISTORY OF RE-ENTRY EVENTS
 3. A BRIEF OVERVIEW OF RE-ENTRY ANALYSISTOOLS
  3.1 Spacecraft Atmospheric Re-entry and AerothermalBreak-up (SCARAB)
  3.2 Object Re-enrty Survival Analysis Tool (ORSAT)
  3.3 Debris Assessment Software (DAS)
  3.4 Debris Risk Assessment and Mitigation Analysis
  3.5 Semi-analytic Tool for End of Life Analysis Software(STELA)
 4. APPLICATION OF THE NEW SOLUTION TO THEUPCOMING TIANONG-1 RE-ENTRY
 5. CONCLUSION
 ACKNOWLEDGMENTS
 REFERENCES

• Eun-Jung Choi(Korea Astronomy and Space Science Institute, Daejeon 34055, Korea)
• Sungki Cho(Korea Astronomy and Space Science Institute, Daejeon 34055, Korea)
• Deok-Jin Lee(School of Mechanical Automotive Engineering, Kunsan National University, GunSan 54150, Korea) Corresponding Author
• Siwoo Kim(Department of Aerospace Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea)
• Jung Hyun Jo(Korea Astronomy and Space Science Institute, Daejeon 34055, Korea, Korea University of Science and Technology, Daejeon 34133, Korea)