The S-IVB also continued to thrust at a small degree by venting gaseous hydrogen, to help keep propellants settled of their tanks and prevent gaseous cavities from forming in propellant feed traces. This venting also maintained Risk-free pressures as liquid hydrogen boiled off in the gas tank. This venting thrust conveniently exceeded aerodynamic d

Initially, NASA dismissed LOR as being a riskier choice, as a space rendezvous experienced still to get carried out in Earth orbit, significantly less in lunar orbit. Various NASA officers, including Langley Investigate Heart engineer John Houbolt and NASA Administrator George Small, argued that a lunar orbit rendezvous provided The best landing ab