Comprehensive analysis of low- and high-enriched uranium nuclear thermal propulsion for manned mars missions

Abstract

Recent studies show that a Mars capable Nuclear Thermal Propulsion (NTP) system utilizing a core fueled with nuclear power plant grade Low-Enriched Uranium (LEU) rather than weapons grade High-Enriched Uranium (HEU) is achievable from a neutronics, system mass, and performance perspective. This discovery fundamentally changes the conversation surrounding NTP, as the Global Threat Reduction Initiative (GTRI) commits the US to the "minimization of use of highly enriched uranium, where technically and economically feasible." Now that LEU has been technically proven, the economic advantages of both alternatives must be thoroughly evaluated prior to any significant investment. This paper presents a first attempt at such a cost analysis by investigating the key mission life-cycle phases prior to launch, as development costs are the most limiting factor to NTP mission success. An overview of the relevant policy and testing history will be provided, followed by a more detailed presentation of the major factors predicted to affect mission costs, i.e. licensing, fuel development, qualification and testing, and assembly, test, and launch operations (ATLO). Preliminary results suggest that, while not as straight-forward as initially hypothesized, the collective development cost savings of an LEU-NTP mission are enough to justify its continued progress.