Effect of orbital characteristics of asteroid defense satellites on their defense range

Abstract

The study on the near-Earth asteroid is crucial for the stability of the Earth's ecosystem, the protection of species diversity, and the safety of human civilization. Kinetic impact is an effective option for defense against near-Earth asteroids, and several studies have focused on launching defense satellites from the Earth's surface for asteroid interception. This paper explores a space-based defense, namely, the deployment of defense satellites in high Earth orbit to deliver emergency kinetic impacts against near-Earth asteroids that threaten the Earth. Furthermore, this paper delves into the impacts of various orbital characteristics on the effective defense range of a defense system. By considering the maximum orbit change capability of the orbit control engine of the defense satellites as a constraint, the effects of different semi-major axis length, eccentricities, and inclination of the satellite orbit on the defense range were investigated by solving the Lambert problem in a two-body model. Results revealed that the effective defense range of the satellite orbit increases with the increase in the semi-major axis length, decreases with the increasing eccentricity, and initially decreases with increasing inclination, gradually increases thereafter, and reaches a minimum value at 90°. The study comprehensively investigates the performance characteristics of space-based systems that are effective for optimizing the orbital configurations of satellites, further improving the overall effectiveness of emergency against near-Earth asteroids.