Friday, March 2, 2012

On learning to walk — in space

Recalling the early evolution of the EVA

by Patrick J. Walsh

March 18 marks the 47th anniversary of the first spacewalk. On that date in 1965, Soviet cosmonaut Alexei Leonov passed through an inflatable airlock to exit the Voskhod 2 spacecraft and ‘float’ in open space at the end of a 50 foot tether, becoming the first human being to perform an EVA (“extravehicular activity,” in the technical vernacular).

The astronauts of the American Gemini program took their first ‘steps’ in space shortly after Leonov, beginning with Ed White’s landmark EVA on June 3, 1965, during Gemini 4. The U.S. followed White’s feat with a series of spacewalks focused on developing the ability to do useful work while floating in the weightlessness of open space, and along the way, a succession of U.S. spacewalkers encountered a variety of difficulties in controlling their movements and achieving their objectives.

Ed White achieves the first
American spacewalk, June 3, 1965.

Photo courtesy of NASA.
By the conclusion of the Gemini program, during Gemini 12 in November, 1966, the persistent effort to master the art of the EVA paid dividends for NASA’s astronaut team. Through a combination of careful study with his fellow astronauts and innovations in training, tools and equipment, Buzz Aldrin proved during the Gemini 12 flight that a carefully planned extravehicular activity could be carried out without undue hardship or risk.

While the U.S. developed its EVA capability, the Soviets made no attempt to follow up on Leonov’s achievement until the Soyuz 5 mission in January, 1969. Just six months later, the very term “EVA” would take on a whole new dimension during Apollo 11, when Neil Armstrong and Buzz Aldrin would make the first extravehicular activity on solid ground — as the first human beings to walk on the surface of the Moon.

See the “Evolution of the EVA,” in the latest episode of my video series “Five Minutes in Space,” at: 

© 2012 Patrick J. Walsh

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