Mission Orbit Design of CubeSat Impactor Measuring Lunar Local Magnetic Field

Abstract

The current study designs the mission orbit of the lunar CubeSat spacecraft to measure the lunar local magnetic anomaly. To perform this mission, the CubeSat will impact the lunar surface over the Reiner Gamma swirl on the Moon. Orbit analyses are conducted comprising Delta V and error propagation analysis for the CubeSat mission orbit. First, three possible orbit scenarios are presented in terms of the CubeSat's impacting trajectories. For each scenario, it is important to achieve mission objectives with a minimum Delta V since the CubeSat is limited in size and cost. Therefore, the Delta V needed for the CubeSat to maneuver from the initial orbit toward the impacting trajectory is analyzed for each orbit scenario. In addition, error propagation analysis is performed for each scenario to evaluate how initial errors, such as position error, velocity error, and maneuver error, that occur when the CubeSat is separated from the lunar orbiter, eventually affect the final impact position. As a result, the current study adopts a CubeSat release from the circular orbit at 100 km altitude and an impact slope of 15 degrees, among the possible impacting scenarios. For this scenario, the required Delta V is calculated as the result of the Delta V analysis. It can be used to practically make an estimate of this specific mission's fuel budget. In addition, the current study suggests error constraints for Delta V for the mission.