Moon Landing: 40th Anniversary

"Crescent Earth." The crescent Earth rises above the lunar horizon in this spectacular photograph taken from the Apollo 17 spacecraft in lunar orbit during final lunar landing mission in the Apollo program. (Photo courtesy NASA)

On July 20, 1969 -- 40 years ago today -- Astronaut Neil Armstrong stepped onto the moon, recording the famous words, "It's one small step for man, one giant leap for mankind." Visit the NASA Web site to view the video clip of this historic event and more photos and videos of research and history of the NASA Space Program.