US space nuclear power development challenges

U.S. space nuclear programs face significant logistical, supply chain, and financial hurdles as NASA and industry partners work toward lunar exploration goals. Experts have identified cost, production, and insurance limitations as primary obstacles. Specifically, the lack of insurance or indemnity options for private commercial missions carrying radioactive materials remains a concern.

To support a lunar surface base by 2030, industry leaders are considering americium-241 as an alternative to the scarce plutonium-238. However, americium is expensive and requires high levels of coordination between NASA, the Department of Energy, and commercial entities.

A critical bottleneck remains the lack of a dedicated production line for ceramic high-assay low-enriched uranium (HALEU) fuels, which are necessary for both space applications and terrestrial small modular reactors. While the Department of Energy is currently the sole domestic supplier, it has recently allocated fuel to NASA for the Space Reactor 1 (SR-1) Freedom mission and to the company Radiant.

NASA is advancing its technical roadmap through the Space Power and Reactor Capabilities (SPARC) contract. This proposed multiple-award contract aims to support the design, development, testing, and certification of space nuclear systems. A primary focus is the Lunar Reactor-1 (LR-1) program, which targets a 2030 landing. The LR-1 Phase 1 tasks are expected to focus on hardware and flight-oriented design, aiming for a 20 kWe output using HALEU fuel. NASA is currently seeking industry feedback on the draft SPARC solicitation.