Target selection for a small low-thrust mission to near-Earth asteroids
low-thrust, asteroid selection, near-Earth asteroids, mission analysis
The preliminary mission design of spacecraft missions to asteroids often involves, in the earlyphases, the selection of candidate target asteroids. The final result of such an analysis is a listof asteroids, ranked with respect to the necessary propellant to be used, that the spacecraftcould potentially reach. In this paper we investigate the sensitivity of the produced asteroidsrank to the employed trajectory model in the specific case of a small low-thrust propelledspacecraft beginning its journey from the Sun–Earth L2 Lagrangian point and heading to arendezvous with some near-Earth asteroid. We consider five increasingly complex trajectorymodels: impulsive, Lambert, nuclear electric propulsion, nuclear electric propulsion includingthe Earth’s gravity, solar electric propulsion including the Earth’s gravity and we studythe final correlation between the obtained target rankings. We find that the use of a low-thrust trajectory model is of great importance for target selection, since the use of chemicalpropulsion surrogates leads to favouring less attractive options 19% of times, a percentagethat drops to 8% already using a simple nuclear electric propulsion model that neglects theEarth’s gravity effects and thrust dependence on the solar distance. We also find that for thestudy case considered, a small interplanetary CubeSat named M-ARGO, the inclusion of theEarth’s gravity in the considered dynamics does not affect the target selection significantly.
Tsinghua University Press
Alessio Mereta,Dario Izzo,Target selection for a small low-thrust mission to near-Earth asteroids.Astrodyn.2018, 2(3): 249–263.