December 17, 1957 – first launch of the Atlas rocket by U.S.
Designed in the late 1950s, the Atlas rocket is the name of a family of U.S. space launch vehicles. The Atlas is a liquid-fuel rocket with three multi-stage engines. During ascent, Atlas would jettison two of its three engines. The Atlas V rocket is currently used by the U.S. The first successful test-launch of an Atlas rocket took place December 17, 1957.
Atlas missile launch from Cape Canaveral in 1957
Read more about the Atlas rocket in Wikipedia