Third generation commercial solar electric propulsion: A foundation for space exploration missions

Solar Electric Propulsion (SEP) has become vital in several commercial space applications and is well positioned to lower the cost and risk of important space exploration and science missions. The success of commercial SEP in the global satellite market provides a production base that produces cost-effective hardware. Well-established commercial approaches are in place for scaling and tailoring SEP systems to US government missions. An evolutionary roadmap is discussed, illustrating how these capabilities have emerged from the privately funded commercial technology branching into two new applications to government exploration missions. One is the adaptation for deep space exploration as illustrated by the NASA Discovery class mission to the main belt asteroid 16 Psyche that will use currently-available commercial SEP technologies with only minor modifications. The second enables the emergence of large scale space transportation as embodied by the Power Propulsion Element (PPE), derived from the Asteroid Redirect Robotic Mission (ARRM) spacecraft concept and planned as the bus foundation of the Deep Space Gateway (DSG). The PPE could use high-power third generation SEP derived from commercial capabilities to transport and maintain large habitats and modules within the Earth-Moon system.