This was a Dell Comic book (#716) from 1956. It is a "novelization" of the Disney films "Man in Space" (1955) and "Man and the Moon" (1955). These early influential space films were developed by Walt Disney in collaberation with Wernher von Braun and Willy Ley. These were non-fiction films about the coming space age and were seen by 24 million people.
The book gives a short history of space flight, a discussion of what happens to the human body in space, a trip into orbit, and a voyage around the moon. I am facinated by the cover image which except for the space craft could have been a photograph from the Gemini missions ten years later.
Also found as a 1956 UK reprint as "A World Distributors Movie Classic" ( #45).