The NASA/JSC LUNOX proposal of 1993 tried to reduce the cost of maintaining a First Lunar Outpost by producing liquid oxygen propellant for the return to Earth from lunar soil. This allowed smaller launch and space vehicles, and reduced costs by 33% to 50%. . . . LUNOX tried to use the same [ISRU] strategy to reduce the cost of pioneering small-scale manned lunar exploration as well. This technique would permit drastic downsizing of the manned space vehicles and cost reductions of up to 50%.
The unmanned Phoenix/LUNOX lander would carry a lunar oxygen production plant/storage facility and a nuclear power reactor to the moon's surface. The total mass of this "package" was 12,454 kilograms. The mass summary was as follows:
- Phoenix Unmanned Lander: 4,717 kg dry, 16,578 kg propellants
- Cargo: 12,454 kg
- Translunar Injection Stage: 6,130 kg dry, 43,930 kg propellants Total Mass In Low Earth Orbit 83,809 kg
A second unmanned lander would deliver six small robotic lunar vehicles, after the LUNOX plant and reactor had been deployed. Two "Loader" bulldozers would collect and sort ~500kg/hour of ilmenite-rich lunar soil, which would be fed into the LUNOX plant and processed into liquid oxygen propellant. The process was based on H2 reduction of lunar regolith in a fluidized-bed reactor, solid-state high-temperature electrolysis and Stirling-cycle O2 liquefaction and refrigeration. Two "Tankers" transported the liquid oxygen from the LUNOX factory to other users on the lunar surface ( the annual production capability was 24 000kg, assuming an extraction efficiency of 4% after benefaction
). Finally, two "Haulers" were available for moving heavy equipment across short distances. All rovers use regenerative power sources which were recharged from the nuclear reactor surface power supply.
. . .
- Phoenix Manned Lander (4 X 31 150kn Thrust Engines; 4:1 Throttling): 5505 kg dry; 16944 kg propellants
- Cargo: 2000 kg
- Lh2 Fuel for Return Trip: 2492 kg
- Lunar Oxygen Required: 10,165 kg
The Phoenix was rather unusual since it featured a side-mounted Apollo/FLO type crew capsule for improved pilot visibility during landing, plus centerline propellant tanks and cargo modules for better payload unloading characteristics. The vehicle consisted of a single descent/ascent stage since there was little or no performance advantage to Apollo-type separate stages and lunar orbit rendezvous when using lunar-based propellants. The propulsion and avionics systems were common with the unmanned cargo lander.