A group of eminent international scientists proposed that the year 1957–1958 should be dedicated to worldwide scientific endeavor, to be called the International Geophysical Year (IGY).
The IGY Coordination Committee accepted a U.S. proposal to launch earth-orbiting satellites as part of the effort, and the White House announced on July 29, 1955, that the U.S. would launch a satellite as part of 1957–1958 IGY activities. The Soviet Union submitted a similar proposal at an IGY meeting hosted by the U.S. National Academy of Sciences in June 1957.
Although the IGY satellite project was designed to be primarily a scientific enterprise, the U.S. military services recognized that military benefits might accrue from participating. All three of the services submitted IGY proposals for an earth-orbiting satellite.
The Navy's proposal was selected, because it was felt that NRL's Viking rocket would most likely be considered by the world to be "scientific," whereas the Army and Air Force proposals were based on ICBM technology. (It is also possible that the Army's proposal was rejected in part because its chief engineer was one-time Nazi weapon builder, Werner von Braun, a matter of concern barely ten years after WWII.) A final factor in the selection by the U.S. of the Navy's proposal was a desire not to interfere with ICBM development by the Army and Air Force.
The Naval Research Laboratory (NRL) began briskly preparing for the launch of what was anticipated to be the world's first artificial earth-orbiting satellite as part of the 1957-1958 IGY. What was not fully appreciated (then or now) was the major technological leap forward that would be required for Vanguard. The advanced technology — which included gimbaled rocket motors, advanced fuel pumps, and innovative staging concepts — was conceptually sound but could not be easily accelerated.