How do we go to the Moon?

One of the critical early management decisions made by NASA was the method of going to the Moon. No controversy in Project Apollo more significantly caught up the tenor of competing constituencies in NASA than this one. There were three basic approaches that were advanced to accomplish the lunar mission:

1. Direct Ascent called for the construction of a huge booster that launched a spacecraft, sent it on a course directly to the Moon, landed a large vehicle, and sent some part of it back to Earth. The Nova booster project, which was to have been capable of generating up to 40 million pounds of thrust, would have been able to accomplish this feat. Even if other factors had not impaired the possibility of direct ascent, the huge cost and technological sophistication of the Nova rocket quickly ruled out the option and resulted in cancellation of the project early in the 1960s despite the conceptual simplicity of the direct ascent method. The method had few advocates when serious planning for Apollo began.
2. Earth-Orbit Rendezvous was the logical first alternative to the direct ascent approach. It called for the launching of various modules required for the Moon trip into an orbit above the Earth, where they would rendezvous, be assembled into a single system, refueled, and sent to the Moon. This could be accomplished using the Saturn launch vehicle already under development by NASA and capable of generating 7.5 million pounds of thrust. A logical component of this approach was also the establishment of a space station in Earth orbit to serve as the lunar mission’s rendezvous, assembly, and refueling point. In part because of this prospect, a space station emerged as part of the long-term planning of NASA as a jumping-off place for the exploration of space. This method of reaching the Moon, however, was also fraught with challenges, notably finding methods of maneuvering and rendezvousing in space, assembling components in a weightless environment, and safely refueling spacecraft.
3. Lunar-Orbit Rendezvous proposed sending the entire lunar spacecraft up in one launch. It would head to the Moon, enter into orbit, and dispatch a small lander to the lunar surface. It was the simplest of the three methods, both in terms of development and operational costs, but it was risky. Since rendezvous was taking place in lunar, instead of Earth, orbit there was no room for error or the crew could not get home. Moreover, some of the trickiest course corrections and maneuvers had to be done after the spacecraft had been committed to a circumlunar flight. The Earth-orbit rendezvous approach kept all the options for the mission open longer than the lunar-orbit rendezvous mode.⁴⁹

Inside NASA, advocates of the various approaches contended over the method of flying to the Moon while the all-important clock that Kennedy had started continued to tick. It was critical that a decision not be delayed, because the mode of flight in part dictated the spacecraft developed. While NASA engineers could proceed with building a launch vehicle, the Saturn, and define the basic components of the spacecraft—a habitable crew compartment, a baggage car of some type, and a jettisonable service module containing propulsion and other expendable systems—they could not proceed much beyond rudimentary conceptions without a mode decision. The NASA Rendezvous Panel at Langley Research Center, headed by John C. Houbolt, pressed hard for the lunar-orbit rendezvous as the most expeditious means of accomplishing the mission. Using sophisticated technical and economic arguments, over a period of months in 1961 and 1962 Houbolt’s group advocated and persuaded the rest of NASA’s leadership that lunar-orbit rendezvous was not the risky proposition that it had earlier seemed.⁵⁰

The last to give in was Wernher von Braun and his associates at the Marshall Space Flight Center. This group favored the Earth- orbit rendezvous because the direct ascent approach was technologically unfeasible before the end of the 1960s, because it provided a logical rationale for a space station, and because it ensured an extension of the Marshall workload (something that was always important to center directors competing inside the agency for personnel and other resources). At an all-day meeting on 7 June 1962 at Marshall, NASA leaders met to hash out these differences, with the debate getting heated at times. After more than six hours of discussion von Braun finally gave in to the lunar-orbit rendezvous mode, saying that its advocates had demonstrated adequately its feasibility and that any further contention would jeopardize the president’s timetable.⁵¹

With internal dissention quieted, NASA moved to announce the Moon landing mode to the public in the summer of 1962. As it prepared to do so, however, Kennedy’s Science Adviser, Jerome B. Wiesner, raised objections because of the inherent risk it brought to the crew. As a result of this opposition, Webb back-pedaled and stated that the decision was tentative and that NASA would sponsor further studies. The issue reached a climax at the Marshall Space Flight Center in September 1962 when President Kennedy, Wiesner, Webb, and several other Washington figures visited von Braun. As the entourage viewed a mock- up of a Saturn V first stage booster during a photo opportunity for the media, Kennedy nonchalantly mentioned to von Braun, “I understand you and Jerry disagree about the right way to go to the moon.” Von Braun acknowledged this disagreement, but when Wiesner began to explain his concern Webb, who had been quiet until this point, began to argue with him “for being on the wrong side of the issue.” While the mode decision had been an uninteresting technical issue before, it then became a political concern hashed over in the press for days thereafter. The science advisor to British Prime Minister Harold Macmillan, who had accompanied Wiesner on the trip, later asked Kennedy on Air Force One how the debate would turn out. The president told him that Wiesner would lose, “Webb’s got all the money, and Jerry’s only got me.”⁵² Kennedy was right, Webb lined up political support in Washington for the lunar-orbit rendezvous mode and announced it as a final decision on 7 November 1962.⁵³ This set the stage for the operational aspects of Apollo.