Human exploration and settlement of the moon using lunox-augmented NTR propulsion

An innovative trimodal nuclear thermal rocket (NTR) concept is described which combines conventional liquid hydrogen (LH2)‐cooled NTR, Brayton cycle power generation and supersonic combustion ramjet (scramjet) technologies. Known as the liquid oxygen (LOS)‐augmented NTR (LANTR), this concept utilizes the large divergent section of the NTR nozzle as an ‘‘afterburner’’ into which LOX is injected and supersonically combusted with nuclear preheated hydrogen emerging from the LANTR’s choked sonic throat—‘‘scramjet propulsion in reverse.’’ By varying the oxygen‐to‐hydrogen mixture ratio (MR), the LANTR can operate over a wide range of thrust and specific impulse (Isp) values while the reactor core power level remains relatively constant. As the MR varies from zero to seven, the thrust‐to‐weight ratio for a 15 thousand pound force (klbf) NTR increases by ∼440%—from 3 to 13—while the Isp decreases by only ∼45%—from 940 to 515 seconds. This thrust augmentation feature of the LANTR means that ‘‘big engine’’ perform...