Test Drive | Page 22

Our Progress and Plans on the Journey to Mars With SEP, NASA can also aggregate, refurbish, and reuse Mars transportation infrastructure in a high-energy orbit, such as lunar distant retrograde orbit (LDRO). High performance liquid oxygen and hydrogen propulsion from the SLS Exploration Upper Stage can provide the majority of departure energy, placing payloads in these high-energy orbits and allowing the SEP or SEPhybrid thrusters to initiate the maneuver to Mars. As an added advantage, these maneuvers can be reversed, allowing NASA to capture the Mars return vehicle for refurbishment and reuse. Developing and demonstrating advanced SEP systems early during the Proving Ground missions will accelerate our progress toward sustainable pioneering. The Asteroid Redirect Mission (ARM) provides a near-term opportunity to demonstrate several capabilities important for longer-duration, deep-space missions, including flight-valid ]Y