This month marks the 50th anniversary of the launch of the United States' first satellite to orbit the Earth.

Explorer 1 lifted off Jan. 31, 1958 -- slightly more than a year after the Soviet Union's launch of Sputnik. The White House had asked the Jet Propulsion Laboratory in Pasadena, Calif., and the Army Ballistic Missile Agency to launch a satellite as quickly as possible. JPL designed and built the satellite, the upper stages of the rocket and a tracking system. The Army's Redstone Arsenal produced the liquid-filled rocket.

The launch of Explorer 1 was followed by the creation of the National Aeronautics and Space Administration in October 1958 and transformed JPL from a producer of ballistic missiles to a center for robotic exploration of the solar system and beyond. Today, the California Institute of Technology manages JPL for NASA.

JPL and Caltech have produced a documentary video chronicling the story of Explorer 1 -- "JPL and the Beginnings of the Space Age." The documentary will be telecast nationally on the Discovery Channel's HD Theater, with multiple airings beginning Jan. 31.

Copyright 2008 by United Press International