Statistical Modelling of GEO Debris Environment
- Paper number
IAC-09.A6.P.6
- Author
Dr. Anilkumar A K, Indian Space Research Organization (ISRO), VSSC, India
- Year
2009
- Abstract
The increase of space debris and threats to commercial space activities in the Geosynchronous Earth Orbit (GEO) predictably cause concerns regarding the environment over the long term. Due to very large distance from the earth, the limitations of detecting the Geosynchronous objects increases. Many face faring nations and communities have been undertaking various activities regarding space debris such as detection, modelling, protection and mitigation measures since couple of decades back. Due to the absence of the natural decay mechanism of atmospheric drag to remove debris objects from GEO region and the increasing launch rates in GEO leads to a situation warranting special attention. The GEO debris measurements have been limited to objects with size more than about 60 cm, and hence the scenario has to be expanded for smaller objects, which are untracked. Hence modelling aspects of GEO debris environment has to take momentum and the characterization of the GEO environment is critical for risk assessment and protection of future satellites and also to design effective debris mitigation measures. Modelling of the GEO objects’ environment is very important for the proper analysis and the assessment of conjunction possibilities among the objects in this region. In an earlier paper (Ref. 1) the statistical natures of the characteristics of the tracked GEO debris objects were analysed and statistical models for the orbital parameters namely semi major axis and eccentricity of the objects in the GEO environment were proposed. The operational GEO objects are assumed to be restricted between 34,000 km to 38,000 km, for apogee heights and perigee heights and also in a small inclination band of 0 to 0.1 deg. These operational objects’ two line element (TLE) data have been considered for modelling the semi major axis and eccentricity parameters of GEO objects. The model utilised density distribution of Single Laplace distribution with two parameters, namely location and scale for modelling the semi major axis of GEO objects in the operations range of GEO satellites. The Laplace parameters observed across the years are modelled mathematically, in fact the location parameters do not vary and the scale parameters show a definite trend. In this model the eccentricity distribution selected was log normal distributions. The present paper extends the above model to inclination of the GEO objects. It is found that the inclination of these objects follow the Weibul Distribution and a statistical model based on the Weibul distribution is proposed for inclination. The models for semi major axis and eccentricity are also updated with the recent years TLE data. Further this paper presents an overall integrated environment model for semi major axis, eccentricity and inclination. References (i) Anilkumar, A. K., Ananthasayanam, M. R., and Subba Rao, P. V., “A Simple model for the orbital debris environment in GEO”, Space-2005-A-00070-P0017, 4th European Conference on Space Debris, 18-20 April 2005,Darmstadt, Germany.
- Abstract document
- Manuscript document
(absent)