Exploration Missions 1, 2, and Beyond: First Steps Toward a Sustainable Human Presence at the Moon

During the initial missions of the Space Launch System (SLS) and the Orion spacecraft, NASA will conduct flight tests of these unique and foundational deep space capabilities. The first test flight of the integrated system (EM-1) will launch on an SLS Block 1 with an uncrewed Orion spacecraft to deep space. This will be followed by EM-2, the first crewed test flight, which will also be flown with Orion on an SLS Block 1. In parallel with these missions, the first element (the 50 kilowatt class Power and Propulsion Element) of the lunar Gateway will be delivered by a commercial launch vehicle into a near-rectilinear halo orbit around the Moon. This paper will provide an update on NASA's plans for the first two exploration missions, including the impact of direction in the 2018 U.S. appropriations to build a second, dedicated SLS Block 1B Mobile Launcher on mission planning. The paper will show how a robust, flexible architectural design and planning process has been able to meet changing stakeholder interests while maintaining a strategic focus on advancing plans to extend human presence far beyond low-Earth orbit. The paper will conclude with a preview of how future exploration missions will leverage the capabilities of U.S. government, international partner, and commercial vehicles (a model that was pioneered in low-Earth orbit on the International Space Station) to enable regular access to cislunar space, including anywhere on the lunar surface, in preparation for missions to Mars and beyond.