First US Satellite Launched 1958

The first U.S. satellite, Explorer 1, was launched on January 31, 1958. It was designed and built by the Jet Propulsion Laboratory (JPL) and launched using a Juno I rocket. Explorer 1 carried a cosmic ray detector, which led to the discovery of the Van Allen radiation belts around Earth. The satellite orbited Earth once every 114 minutes and transmitted data until its batteries were exhausted after nearly four months. Explorer 1 remained in orbit until 1970, completing over 58,000 orbits around Earth