Orbit prediction from combining multiple two-line elements

Two-Line Elements(TLE) datasets are the primary source for debris orbits. However, the orbit prediction precision for low earth orbiting space debris using the TLE-SGP4 model is far less than satisfactory. The method of orbit prediction by combining multiple TLE can achieve the purpose of improving orbit predication precision for low earth orbiting space debris. Firstly, this method determined the debris orbit using the TLE-computed positions near the TLE reference epochs as pseudo-observations in the orbit determination, and then to propagate the orbit. The method was tested by continuous TLE data on 5 debris objects at altitude of about 500-600 km during 2009. The orbit prediction results for the method and TLE-SGP4 model were compared using updated TLE data as reference orbit. The 10-day orbit prediction errors for the 5 debris are all less than 5 km using this method, which is significantly less than those from using the TLE-SGP4 model.