MISSION ANALYSIS OF NEAR EARTH ASTEROID EXPLORATION BY MINIATURE ASTEROID INTERCEPTORS

摘要

Discussed in this paper are the results of the mission analysis of near Earth asteroid flyby missions using miniature Asteroid Interceptors. The Interceptor is an autonomous self-contained interplanetary probe with 10kg mass which is now under development in ISAS/JAXA. It has the capability of navigating itself autonomously to flyby the target asteroid using optical navigation system. The image of the asteroid taken by the camera onboard at the closest approach is the main science output of the mission. Firstly discussed is the mission by a single Interceptor, which enables the minimum size interplanetary mission. The interceptor is launched as a piggy back mission on a geostationary mission, separated on a geostationary transfer orbit (GTO), kicked by a solid rocket motor, and injected into an orbit suitable for encountering the asteroid. It is shown that the utilization of the Earth synchronous orbit and the Earth swing-by drastically increase the number of the possible target asteroids, which enables the selection of more scientifically interesting target for a given opportunity. The second mission concept discussed is the multiple asteroids exploration with a single launch. A straightforward application of the single Interceptor mission, that is, the mission by several independent Interceptors is shown firstly, and an option to overcome the difficulty in performing critical operation of multiple spacecrafts simultaneously is also discussed. The list of the target asteroid candidates, detailed mission sequence and maneuver parameters are shown for the assumed example mission.