Lander and Cislunar Gateway Architecture Concepts for Lunar Exploration

As NASA turns its near-term exploration focus back to the cislunar vicinity, attention is on the Gateway and concepts for lunar surface systems to enable both scientific discovery as well as technology demonstration. One objective during a lunar exploration campaign is to support the ultimate goal for Mars extensibility, including flexibility to incorporate enabling technologies as they become available during the lunar exploration campaign, toward a safe and capable human exploration architecture, while at the same time maintaining a reasonable schedule and technical risk posture for near-term exploration goals. The Gateway, a small human-tended facility orbiting around the Moon, supports human and robotic lunar exploration in a manner that creates opportunities for multiple sectors to advance key goals. The lunar vicinity is an ideal location for exploration of the moon. It can support lunar exploration spacecraft parking, refueling, and refurbishment, serve as a point for direct observation of the lunar surface, and serve as a center of control for robotic surface assets. It is, similarly, ideal for Mars missions by offering a location for the outfitting and aggregation of Mars transit vehicles and a place to refuel and restore vehicles that have returned from Mars. Direct exploration of the lunar surface, i.e. not through the Gateway, will be an option that could appear to have a lower cost. However, direct exploration does not create any residual architecture for use in future endeavors. While the Apollo program was a crowning achievement in US spaceflight, it left no residual assets behind for future use. This approach has left us now in the position of having to start future lunar exploration from scratch. Investing in a robust and sustainable architecture, including a Gateway, enables future programs and avoids future costs. Most critically, commercial interests will be much more likely to appear in deep space when there is existing infrastructure to support them and defray mission costs. This paper describes a progressive series of increasingly capable missions, utilizing the Gateway for robotic and human surface lander missions, and discusses the implications of various choices in developing a lunar exploration architecture. The role of a Gateway is examined in a robust lunar exploration program. The importance and value of a Gateway to all exploration options are examined and compared to direct exploration of the lunar surface. Finally, the commercial options and advantages of a robust deep space architecture are discussed. The paper will describe how investments in lunar exploration provide maximum value by leaving a residual architecture to enable commercial endeavors and provide maximum cost benefit both during lunar exploration and beyond.