THORION-1: Deep-Space Interplanetary Transfer Vehicle Powered by Thorium-Water Cycle Plasma-Nuclear Propulsion — Conceptual Architecture, Mission Physics, and Industrial Space-Qualification Simulations
Year: 2026
Type: preprint
Abstract: Complete conceptual design, flight mechanics, and standardized industrial space-qualification simulations for THORION-1, an advanced interplanetary transfer vehicle. The architecture integrates: (1) a molten salt reactor (MSR) utilizing the fertile-to-fissile thorium breeding cycle (232Th -> 233U, 4.2 MWth, 7LiF-BeF2-ThF4-UF4 salt, 1200 K) with passive freeze-plug walk-away safety; (2) closed-loop helium-xenon Brayton conversion generating 1.0 MWe net electrical power; (3) water as a single universal propellant via solid polymer electrolyte (SPE) electrolysis at 20 MPa (15.87 MJ/kg, 7.94:1 O2/H2 stoichiometric ratio); (4) electrodeless plasma propulsion combining Pulsed Inductive Thrusters (PIT/IPPT) and Helicon/ICH (VASIMR-class) engines with magnetic nozzles; and (5) a differential oxygen-injection plasma mode delivering high thrust-to-power (~51 N, Isp 1500-2500 s) for orbital escape, transitioning smoothly to high-Isp hydrogen cruise (Isp 4000-5000 s, ~28 N). The atmospheric launch paradox (T/W << 1) is physically resolved through chemical bipropellant H2/O2 engines (Isp ~370 s, 800 kN total thrust). For an Earth-Mars transfer (5.5 km/s post-LEO delta-v), the plasma propulsion consumes only 12.6 metric tons of propellant versus 99.1 tons for equivalent chemical propulsion (7.8x mass reduction). The repository includes comprehensive industrial space-qualification simulations (TVAC thermal equilibrium, solid-state Marx discharge, 20 MPa electrolysis polarization, freeze-plug scram meltdown, micrometeoroid impact reliability, and NASA GEVS 14.1 g-rms launch random vibration) verified by an automated test suite (36 tests, 100% passing).
Author: Maciel, Tiago Barbosa Dias
Language: English
Subfield: Aerospace Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7214540815