In the early twenty-first century, the Apollo program still is invoked as the ultimate technological achievement. In terms of percentage of the national budget, that effort to land astronauts on the moon was the largest single scientific program ever undertaken by the United States. Six successful lunar landings were accomplished from 1969 to 1972. The twelve astronauts who walked on the surface of the moon collected samples, set up equipment, and conducted scientific experiments. The scientific return from those missions revolutionized people's understanding not only of the moon, but of the earth and the rest of the Solar System. The program also raised many ethical concerns, notably its motivation, the safety of the astronauts, and its cost at the possible expense of other national needs.

The Origins of Apollo

In a speech to Congress on May 25, 1961, President John F. Kennedy stated, "I believe that this nation should commit...