On May 5, 1961, Alan Shepard spent 15 minutes in space. Almost half a century has elapsed since America's first fling with the cosmos. And what ride it has been as witnessed in these images from America In Space: NASA's First Fifty Years by Steven Dick, Robert Jacobs, Constance Moore and Bertram Ulrich, with a foreword by Neil Armstrong.
Fifty Years of American Space Exploration [Slideshow]
NASA celebrates half a century of American spaceflight with a new collection of space exploration images
