<P> In May, 1946, Project RAND had released the Preliminary Design of an Experimental World - Circling Spaceship, which stated, "A satellite vehicle with appropriate instrumentation can be expected to be one of the most potent scientific tools of the Twentieth Century ." The United States had been considering launching orbital satellites since 1945 under the Bureau of Aeronautics of the United States Navy . The United States Air Force's Project RAND eventually released the report, but considered the satellite to be a tool for science, politics, and propaganda, rather than a potential military weapon . In 1954, the Secretary of Defense stated, "I know of no American satellite program ." In February 1954 Project RAND released "Scientific Uses for a Satellite Vehicle," written by R.R. Carhart . This expanded on potential scientific uses for satellite vehicles and was followed in June 1955 with "The Scientific Use of an Artificial Satellite," by H.K. Kallmann and W.W. Kellogg . </P> <P> In the context of activities planned for the International Geophysical Year (1957--58), the White House announced on 29 July 1955 that the U.S. intended to launch satellites by the spring of 1958 . This became known as Project Vanguard . On 31 July, the Soviets announced that they intended to launch a satellite by the fall of 1957 . </P> <P> Following pressure by the American Rocket Society, the National Science Foundation, and the International Geophysical Year, military interest picked up and in early 1955 the Army and Navy were working on Project Orbiter, two competing programs: the army's which involved using a Jupiter C rocket, and the civilian / Navy Vanguard Rocket, to launch a satellite . At first, they failed: initial preference was given to the Vanguard program, whose first attempt at orbiting a satellite resulted in the explosion of the launch vehicle on national television . But finally, three months after Sputnik 2, the project succeeded; Explorer 1 became the United States' first artificial satellite on 31 January 1958 . </P> <P> In June 1961, three - and - a-half years after the launch of Sputnik 1, the Air Force used resources of the United States Space Surveillance Network to catalog 115 Earth - orbiting satellites . </P>

When did the us send its first satellite into space