Trajectories of spacecraft missions with low thrust for delivering ground samples from Main Belt asteroids and Phobos

Trajectories of spacecraft with electro-rocket engine for missions to the Main Belt asteroids Vesta, Fortuna and Mars' satellite Phobos are investigated. The goal of missions — delivering of ground samples to the Earth. For Phobos mission analysis of trajectories is done for a big range of start/finish dates. The payload mass delivered to Phobos is estimated. The difference in payload mass for two models of low thrust: with variable (i.e. “ideal”) and constant jet velocity is considered. The usage of ideal model for calculation and analysis of trajectories is proved.