Laser-Based Thorium Processing and Utilization for In-Situ Nuclear Power Generation in Space Exploration: A Comprehensive Review

Abstract

The growing need for long-duration, high-density energy systems in space has revitalized interest in nuclear fission for extraterrestrial missions. Thorium (Th-232), with its favourable nuclear characteristics, long half-life, and planetary abundance, offers a promising alternative to uranium for compact, low-maintenance power systems on the Moon and Mars. Simultaneously, laser-based materials processing has emerged as a key enabler for precision manufacturing, in-situ resource utilization (ISRU), and real-time elemental analysis in space-like conditions. This review explores the integration of laser-based techniques in the extraction, fabrication, and application of thorium-bearing materials for space nuclear systems. It covers laser ablation and laser-induced breakdown spectroscopy (LIBS) for thorium detection in regolith, laser sintering and melting for fuel preparation, and additive manufacturing approaches for producing radiation-tolerant components. Advances in simulation and thermal modelling of laser–material interactions are reviewed, alongside key challenges such as radioactive handling, microgravity effects, and material degradation. Current experimental gaps and technology readiness limitations are identified, and a development roadmap is proposed. The findings highlight the potential of laser-assisted thorium processing as a critical enabler of sustainable, deployable space nuclear power systems.