Updated Architecture Robustness in NASA's Moon to Mars Capability Development

In preparation for humanity's return to the Moon, it is important to advance technologies and capabilities that will allow for sustainability on the lunar surface, as well as eventual human missions to Mars. As charged in Space Policy Directive-1, NASA's Artemis program will advance and develop technologies on the lunar surface that can be leveraged towards a safe and successful human round-trip mission to Mars. NASA's Human Exploration and Operations Mission Directorate Capabilities Integration Team is advancing a continuous effort to identify and map gaps between exploration capabilities and anticipated human spaceflight architecture elements. As upcoming exploration missions approach, the architectural design tradespace increasingly narrows. This paper provides an updated exploration of certain architectural and element design choices for upcoming missions to the Moon and Mars, comparing and contrasting capability gaps and classes of capability gaps that are architecture robust with those that are not. In doing so, we identify certain capabilities as relevant, and therefore robust, across varying architectural possibilities while identifying other capabilities as only applicable to specific architectural pathways. Capabilities that are applicable to multiple elements across the architecture have more architectural breadth because of their increased likelihood of remaining relevant even if changes are made to some elements they are mapped to. Correspondingly, capabilities that are applicable to specific elements across the architecture but are necessary under almost any eventuality have more architectural depth because of their increased likelihood of remaining relevant even if architecture changes are made. One of the key analyses in this paper is an exploration of architecture robustness as a function of capability area, as defined by the NASA Technology Taxonomy. These results are then evaluated and analyzed across human spaceflight architecture elements to gain a greater understanding of the relationships between exploration capabilities and the systems that will eventually be implemented, as well as investigating the commonalities of capabilities across elements. General conclusions about these relationships are drawn.