Physics / mechanism
ISRU extracts and processes raw materials at the point of use—Moon, Mars, asteroids—rather than launching them from Earth. Core processes: regolith oxygen extraction via molten electrolysis (FFC Cambridge process, ~40 wt% O₂ recoverable from lunar ilmenite), carbothermal reduction, and water-ice electrolysis for H₂/O₂ propellant. Sintering and binder-jet printing of regolith enables structural components in situ. Key parameters: power density (systems currently require 10–100 kW continuous), throughput (kg/hr of oxygen or metal), and feedstock variability tolerance. NASA’s MOXIE on Perseverance demonstrated ~6g/hr CO₂→O₂ on Mars at TRL 7. Lunar ISRU remains TRL 3–5 outside MOXIE-class demonstrations.
Competitive landscape
Earth-based analogy is remote mining plus on-site processing—competing logic is simply launching consumables, which scales poorly above ~$2k/kg to LEO. Adjacent approaches: atmospheric ISRU (Mars CO₂ cracking), volatile extraction from permanently shadowed craters, and asteroid redirect for near-Earth processing. Key players: Redwire, Space Forge, Astrobotic, ispace, and NASA/ESA in-house programs.
Companies using
Connected ideas
Sources
Frontier (open questions)
- To be added.