While I was leading a tour of the National Air and Space Museum in January 2026, a visitor posed this insightful question: “Why has it taken so long to return to the Moon?”
After all, NASA had the know-how and technology to send humans to the lunar surface more than 50 years ago as part of the Apollo program. And, as another tour guest reminded us, computers today can do so much more than they could back then, as evidenced by the smartphones most of us carry in our pockets. Shouldn’t it be easier to get to the Moon than ever before?
The truth is that sending humans into space safely continues to be difficult, especially as missions increase in complexity.
The Artemis II SLS rocket and Orion spacecraft Integrity en route from the vehicle assembly building to Launch Complex 39B at the Kennedy Space Center, Jan. 17, 2026.
NASA/John Kraus
New technologies require years of study, development and testing before they can be certified for flight. And even then, systems and materials can behave in ways that surprise and worry engineers and mission planners; look no further than Boeing’s Starliner CFT mission or the performance of the Orion heat shield on Artemis I.
Issues with Starliner’s thrusters led NASA to return the spacecraft from the International Space Station without its crew. Unanticipated chipping of the Orion heat shield resulted in years of research, culminating in NASA altering the atmospheric reentry plans for the Artemis II mission.
NASA’s programs also require sustained political will and financial support across multiple presidential administrations, Congresses and fiscal years. As a historian of human spaceflight, I have studied the space agency’s efforts to engage the broader public to convince American taxpayers that their programs hold value for the nation.
NASA is now on the eve of the first crewed flight to the Moon since the Apollo era: Artemis II. A crew of four will conduct a lunar flyby, laying the groundwork, the agency hopes, for a landing on the Artemis IV mission.
The story of NASA’s effort to return humans to the Moon is long and winding, demonstrating the complexities of turning grand ambitions into real missions.
Post-Apollo
In early 1970, with two successful Moon landings on the books, President Richard Nixon sought to reduce NASA’s budget to better align with his administration’s priorities. This decision put the space agency in a difficult position, which ultimately led to the cancellation of three planned Apollo missions to conserve funding for its plans for long-term human activity in low Earth orbit.
NASA repurposed the third stage of a Saturn V rocket to create the first U.S. space station, Skylab, which operated from 1973 to 1974. The space agency used leftover Saturn IB rockets and Apollo command and service modules to send crews to the station.
Over the next three decades, NASA developed and operated the space shuttle. The…


