Preliminary Determination of Footprint Area of Uncontrolled Space Debris: Case Study of Tiangong-1 Space Station

Nizam Ahmad(1*), Elisa Fitri(2)

(1) Indonesian National Institute of Aeronautics and Space (LAPAN)
(2) Departemen Astronomi, Institut Teknologi Bandung (ITB)
(*) Corresponding Author


Indonesia is an archipelagic country consisting of 16,056 islands and covering a vast area around 5,120km x 1,760km. With the largest coastline in the world, Indonesia is vulnerable to the fall of human-made objects from space. Furthermore, the space objects placed at polar and equatorial regions pass over the equatorial region, including Indonesia, more frequently around 4 and 9 times a day, successively depending on their altitudes. Due to the significant probability of the passages, determining the footprint of falling space objects (debris) is mandatory. Therefore, this study examines the demise of Tiangong 1 as a case study. First, trajectory propagation was carried out to track the re-entry point resulting in an estimated footprint area of around 2,632 km x 2,698 km over the Sothern Pacific Ocean.  Second, a mathematical formulation in Astrodynamics was applied to engage a series of assumptions, which led to a more cramped footprint area of around 193km x 12km over a small portion of the South Pacific Ocean. Since the orbital prediction is fraught with great uncertainty, it was very likely that the Tiangong-1 debris fell over the Southern Pacific Ocean of the order of thousands of kilometers.


Footprint area; Tiangong-1; Space debris

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Choi, E. J., Cho, S., Lee, D. J., Kim, S., & Jo, J. H. (2017). A study on re-entry predictions of uncontrolled space objects for space situational awareness. Journal of Astronomy and Space Sciences, 34(4), 289–302.

Csillik, I. S. (2017). Analysis and Prediction of Tiangong-1 Reentry Analysis and Prediction of Tiangong-1 Reentry. Romanian Astron. J., 27(3).

Falsone, A., Noce, F., & Prandini, M. (2014). A randomized approach to space debris footprint characterization. IFAC Proceedings Volumes, 47(3), 6895–6900.

Kelso, T. S., Parkhomenko, N. N., Shargorodsky, V. D., Vasiliev, V. P., Yurasov, V. S., Nazarenko, A. I., Tanygin, S., & Hiles, R. M. (2013). What Happened to BLITS ? An Analysis of the 2013 Jan 22 Event. The 14th Annual Advanced Maui Optical and Space Surveillance Conference (AMOS), September.

Kennewel, J. (1999). Satellite Orbital Decay Calculations. In IPS

Radio and space Service. Weather/Space Weather Effects/SatelliteOrbitalDecayCalculations.pdf

Klinkrad, H. (2006). Space Debris Models and Risk Analysis. In Springer-Verlag Berlin Heidelberg New York. Praxis Publishing.

Larson, W. J., & Wertz, J. R. (1999). Spacecraft Mission Analysis and Design. California and Kluwer Academic Publishers. Engineering/Space_Mission_Analysis_and_Design.pdf

Lin, H. Y., Zhu, T. L., Liang, Z. P., Zhao, C. Y., Wei, D., Zhang, W., Han, X. W., Zhang, H. F., Wei, Z. Bin, Li, Y. Q., Xiong, J. N., Zhan, J. W., Zhang, C., Ping, Y. D., Song, Q. L., Zhang, H. T., & Deng, H. R. (2019). Tiangong-1’s accelerated self-spin before reentry. Earth, Planets and Space, 71(1).

NASA. (2014). Orbital debris. In Orbital Debris Quarterly News (Vol. 18, Issue 1, pp. 1–10).

Pardini, C., & Anselmo, L. (2013). Reentry predictions of three massive uncontrolled spacecraft. The 6th IAASS Conference –Safety Is Not an Option, May.

SIA. (2017). State of the Satellite Industry Report (Issue June).

Stamminger, A. (2007). Atmospheric re-entry analysis of sounding rocket payloads. The 18th ESA Symposium on European Rocket and Balloon Programmes and Related Research, June, 1–15.

Stansbery, E. G. (2004). Growth in the number of SSN tracked orbital objects. The 55th International Astronautical Congress of the International Astronautical Federation, the International Academy of Astronautics, and the International Institute of Space Law, 1–5.

Tan, A., Zhang, T. X., & Dokhanian, M. (2013). Analysis of the Iridium 33 and Cosmos 2251 Collision Using Velocity Perturbations of the Fragments. Advances in Aerospace Science and Applications, 3(1), 13–25.

Vallado, D. A. (2001). Fundamentals of astrodynamics and applications. McGraw-Hill.

Vallado, D. A., Crawford, P., Hujsak, R., & Kelso, T. S. (2006). Revisiting spacetrack report #3. AIAA/AAS Astrodynamics Specialist Conference and Exhibit, August.

Vellutini, E., Bianchi, G., Perozzi, E., Pardini, C., Anselmo, L., Pisanu, T., Di Lizia, P., Piergentili, F., Monaci, F., Reali, M., Villadei, W., Buzzoni, A., Amore, G. ., & Muolo, L. (2020). Monitoring the final orbital decay and the re-entry of Tiangong-1 with the Italian SST ground sensor network. Journal of Space Safety Engineering, 7(4), 487–501.

Weaver, M. A., Baker, R. L., & Frank, M. V. (2001). Probabilistic estimation of reentry debris area. The 3rd European Conference on Space Debris, ESOC, March.


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Accredited Journal, Based on Decree of the Minister of Research, Technology and Higher Education, Republic of Indonesia Number 225/E/KPT/2022, Vol 54 No 1 the Year 2022 - Vol 58 No 2 the Year 2026 (accreditation certificate download)

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