In 1961, Ham was the first primate in space.
Ham’s name was an acronym for H olloman A ero M ed. His sub-orbital flight aboard the Redstone Mercury rocket was very similar to the flight that Alan Shepard would take later that year.
In 1958, the U.S. launched their first artificial satellite, Explorer 1.
Following the launch of the Soviet Union’s Sputnik 1 on October 4, 1957, the U.S. Army Ballistic Missile Agency was directed to launch a satellite.
Learn more at http://www.jpl.nasa.gov/explorer/history/