Ending Apollo

When the Apollo 17 spacecraft carrying U.S. astronauts Gene Cernan, Harrison Schmitt, and Ron Evans returned to Earth on December 19, 1972, the Apollo lunar landing program came to its end. No human has set foot on the Moon’s surface since.

This ending was not what NASA had hoped for. In July 1969, at the time of Apollo 11, NASA was preparing for nine more missions to the lunar surface, climaxing with the Apollo 20 mission scheduled for December 1972. There were no plans for more Apollo missions after Apollo 20. NASA was eager to move on to even more ambitious undertakings.

Just over a year after the first humans stepped on the Moon, three Apollo missions had been canceled; the Apollo lunar landing program would end prematurely. The developments leading to the cancelation of those three Apollo missions, the mission previously designated Apollo 15 and the final two planned missions, Apollo 19 and Apollo 20, are detailed in my book After Apollo: Richard Nixon and the American Space Program.

The first mission to go was Apollo 20. Out of NASA’s planning for what should follow the lunar landing missions there had emerged the concept of an interim step to establishing a permanent U.S. presence in space. An experimental space station (which would eventually be called Skylab) would use a much-modified third stage of the massive Saturn V Apollo launch vehicle as the basis for an outpost that could support a three-person crew for longer duration missions than were possible with the Apollo spacecraft. After the successful Apollo 11 and Apollo 12 missions, and in anticipation of lower future budgets and the possible shutdown of Saturn V production, NASA decided that using one of the existing Saturn Vs for constructing and launching that experimental space station had higher priority than one more lunar landing mission. On January 4, 1970, a stop work order was issued canceling preparations for Apollo 20.

As NASA’s budget was being debated in December 1969, one of President Richard Nixon’s top aides told NASA that the “the President says that he doesn’t have enough money within the next couple of years and must accept limitation of [space] activity” and that Nixon “did not see the need to go to the moon six more times.” That attitude coming from the president put NASA in a difficult position. The space agency had requested funds for the remaining Apollo missions but also to study NASA’s top post-Apollo priorities in human spaceflight, a 12-person permanent space station and a reusable system to bring supplies and crew to the station and back—a space shuttle.

In January 1970, the White House asked Congress to provide NASA with a budget of $3.3 billion, a reduction of 15 percent from the preceding year’s allocation. It also indicated that the NASA budget was unlikely to increase in subsequent years. In a space policy statement released in March 1970, President Nixon said that “space expenditures must take their proper place within a rigorous system of national priorities.”

The reduced budget request and Nixon’s statement implying a lower priority for space activities sent a message to NASA leadership. That message was that there was essentially no possibility over the next few years of NASA getting the funds needed to support all the agency’s current plans and post-Apollo ambitions. Something had to give.

Another consideration was the high risk of each Apollo mission. NASA had put a herculean effort into making each Apollo flight as safe as possible, but its managers knew that the risk could not be reduced to zero. Some influential people among the NASA leadership, most notably deputy administrator George Low and Robert Gilruth, director of the Manned Spacecraft Center (later renamed the Johnson Space Center) noted that President Kennedy’s goal of sending Americans to the Moon had been met. There was no compelling reason to accept the risk of subsequent missions. In an authoritative account of the Apollo program, Gilruth was quoted as saying that Apollo flights should “stop now, before we lose someone.” This existing concern was reinforced by the near-fatal Apollo 13 accident in April 1970.

NASA leadership met in mid-July 1970 to formulate the agency’s plans for the next five to 10 years. One result of this discussion was to abandon plans for simultaneous development of the large space station and the space shuttle. Instead, the shuttle would be developed first and only after it was flying would space station development begin. The NASA managers also decided to propose to the White House canceling two of the remaining six Apollo missions, Apollo 15 and Apollo 19. The originally-planned Apollo 15 was the last mission using the original lunar landing module with its limited capabilities. Apollo 19 would use an enhanced module capable of staying longer on the Moon and carrying a lunar roving vehicle so the astronauts could travel farther from their landing location. Canceling the two missions was estimated to save $800 million.

The scientific community interested in planetary science had been eagerly awaiting the enhanced scientific capabilities of the final three Apollo missions. NASA felt it had to consult with that community before finalizing its decision to cancel Apollo 19. Not surprisingly, there was strong scientific opposition to that move. Even Nixon’s science adviser Lee DuBridge expressed his hope that the mission could be retained.

None of these arguments changed NASA’s thinking—that the prudent course of action was to fly Apollo 14 in January 1971, to cancel Apollo 15 and Apollo 19, and to renumber Apollo 16-18 as Apollo 15, Apollo 16, and Apollo 17, with Apollo 17 being the final lunar landing mission. NASA Administrator Thomas Paine informed President Nixon of NASA’s decision on September 1, telling the president that “the most compelling reason for the decision to cancel these flights, which we have arrived at reluctantly but with overwhelming consensus, is the current and reasonably austere funding situation for NASA.” Another reason, Paine told Nixon, was “the risks involved in these difficult missions.”

The decision to bring Apollo to a premature end had several parents. President Richard Nixon and his White House policy and budget advisers, with the consent of Congress, held NASA to a tightly constrained budget that forced the choice between canceling planned Apollo missions or getting started on future programs. It was NASA leadership that proposed not flying all remaining Apollo missions so NASA could begin the space shuttle program. The American public seemed indifferent to continuing Apollo missions, so there were no negative political consequences from canceling the two missions.

The Apollo lunar landing program was a magnificent achievement. However, its impact on what would follow was limited. The United States in 1970 decided to retreat from human exploration of the Moon and beyond.

Dr. John M. Logsdon is the founder and long-time director of George Washington University's Space Policy Institute and Professor Emeritus at the Elliott School of International Affairs. He is author, among many articles, essays, and edited books, of the award-winning studies John F. Kennedy and the Race to the Moon (2010); After Apollo? Richard Nixon and the American Space Program (2015); and Ronald Reagan and the Space Frontier (2019). 

Sources

John M. Logsdon, After Apollo: Richard Nixon and the American Space Program (New York: Palgrave Macmillan, 2015), especially Chapter 6. Unless otherwise noted, quoted material is taken from this account.

Andrew Chaikin, A Man on the Moon: The Voyages of the Apollo Astronauts (New York: Viking, 1993), 286.