Apollo was one of the most expensive American scientific programs ever. It cost more than $20 billion in 1960s dollars or an estimated $206 billion in present-day US dollars. (In comparison, the Manhattan Project cost roughly $26.3 billion, accounting for inflation.) It used the Saturn rockets as launch vehicles, which were far bigger than the rockets built for previous projects. The spacecraft was also bigger; it had two main parts, the combined command and service module (CSM) and the lunar landing module (LM). The LM was to be left on the Moon and only the command module (CM) containing the three astronauts would eventually return to Earth.
Armstrong in July 1969
The second manned mission, Apollo 8, brought astronauts for the first time in a flight around the Moon in December 1968. Shortly before, the Soviets had sent an unmanned spacecraft around the Moon. On the next two missions docking maneuvers that were needed for the Moon landing were practiced and then finally the Moon landing was made on the Apollo 11 mission in July 1969.
The first person to stand on the Moon was Neil Armstrong, who was followed by Buzz Aldrin, while Michael Collins orbited above. Five subsequent Apollo missions also landed astronauts on the Moon, the last in December 1972. Throughout these six Apollo spaceflights, twelve men walked on the Moon. These missions returned a wealth of scientific data and 381.7 kilograms (842 lb) of lunar samples. Topics covered by experiments performed included soil mechanics, meteoroids, seismology, heat flow, lunar ranging, magnetic fields, and solar wind The Moon landing marked the end of the space race; and as a gesture, Armstrong mentioned mankind when he stepped down on the Moon.
Armstrong on the Moon
Apollo set major milestones in human spaceflight. It stands alone in sending manned missions beyond low Earth orbit, and landing humans on another celestial body. Apollo 8 was the first manned spacecraft to orbit another celestial body, while Apollo 17 marked the last moonwalk and the last manned mission beyond low Earth orbit to date. The program spurred advances in many areas of technology peripheral to rocketry and manned spaceflight, including avionics, telecommunications, and computers. Apollo sparked interest in many fields of engineering and left many physical facilities and machines developed for the program as landmarks. Many objects and artifacts from the program are on display at various locations throughout the world, notably at the Smithsonian's Air and Space Museums.
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