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Buzz on GeminiAstronaut Edwin "Buzz" Aldrin snaps a self-portrait while spacewalking during NASA's Gemini 12 mission in November 1966. Part of a camera (foreground) and the antenna of an unmanned Agena target vehicle—used during the Gemini program for rendezvous and docking practice—are visible in the left corner of the frame.The newly released picture is among thousands of high-resolution digital scans that are being created as part of the Project Gemini Online Digital Archive. (Also see "Buzz Aldrin, First Man (to Pee) on the Moon, Sounds Off.")Project Gemini (1964 to 1966) was the second U.S. human spaceflight program. It came after the Mercury missions, which lofted the first U.S. astronauts into orbit, but before the Apollo spaceflights, which included the first moon landing in 1969.(Read about the Apollo 11 moon-landing mission in a 1969 National Geographic magazine article.) The specific goals of Gemini included practicing rendezvous and docking between two crewed spacecraft, successfully undertaking extravehicular activities (aka spacewalking), perfecting reentry procedures, understanding the effects of the space environment on humans, and testing systems for the upcoming Apollo spacecraft. "Those sorts of lessons about how things worked and how to operate in space were really critical in getting to the moon," said NASA chief historian William Barry.—Ker Than

Photograph courtesy Arizona State University/NASA