Mars Missions Using Solar Electric Propulsion

Successful demonstration of solar electric propulsion on the Deep Space 1 technology demonstration mission has paved the way for the use of this technology on future planetary missions. Currently there is much interest in retrieving Mars surface samples for scientific exploration, as well as developing the technology to enable human missions to Mars sometime in the next few decades. Solar electric propulsion trajectories for Mars opportunities in the 2004-2011 time frame are examined. All of the trajectories shown were optimized with a gradient-based calculus-of-variations tool. In addition, a genetic algorithm was used to search for more nonstandard trajectories. Mission performance is presented as burnout mass along contours of constant flight time. The superior specific impulse of these propulsion systems results in a larger delivered mass at Mars than a conventional chemical mission. A very curious feature of these missions is that for longer flight times, solutions exist that permit a nearly continuous launch opportunity over an entire Earth-Mars synodic period. (Author)