The Precision Orbit Determination of Asteroid Based on Optical and Radar Data

Objectives: In order to serve the implementation of China's deep space exploration programs, we develop software for asteroid orbit determination that can handle multiple sources of measured data. Methods: The precision orbit of the asteroid Toutatis is investigated by using its measured data (optical and radar data observed during the period 1976-2022), and the orbit determination results were compared with the Toutatis ephemeris, which verified the reliability of the software. Results: The orbit determination results show that the position uncertainty of the precision orbit of the asteroid calculated by combining optical and radar data is 1.9 km in the sense of 3, and the orbital position uncertainty calculated by optical data alone is 8.818 km, indicating that the introduction of radar data can effectively reduce the orbital determination error of asteroids. Conclusions: The final orbit determination result reached the engineering level, and the accuracy of the asteroid ephemeris was consistent, which showed the correctness of the self-developed asteroid orbit determination software that can process multi-source measured data.