Explorer 1 was the first satellite launched by the United States when it was sent into space on January 31, 1958. 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 using its Jupiter C rocket developed under the direction of Dr. Wernher von Braun. The Jet Propulsion Laboratory received the assignment to design, build and operate the artificial satellite that would serve as the rocket's payload. JPL completed this job in less than three months.

The staff of JPL Archives selected four audio clips from interviews conducted with William Pickering, Al Hibbs, and Homer Joe Stewart. For more information on Explorer 1 and the people who contributed to its success, please contact the JPL Archives.

William Pickering (1910-2004)

In 1958, as Director of JPL, Pickering led the successful effort to place the first U.S. satellite, Explorer 1, into Earth orbit. Following on the success of Explorer 1, Pickering was instrumental in leading a new era of robotic space exploration, including the first missions to the moon and the planets. He was Director of JPL from 1954-1976. In this 1989 interview with Michael Hooks, Pickering discusses the night of the launch and repercussions for JPL and NASA.

Transcript and Audio Clip (5:00 minutes)

Homer Joe Stewart (1915-2007)

Homer Joe Stewart was an aerospace engineer and rocket propulsion expert. He was heavily involved in developing Explorer 1, and later went on to become the director of NASA's program planning and evaluation office. After his service at NASA, he returned to Caltech, his alma mater, where he taught in the aeronautics department. In his 1972 interview with James Wilson, he discussed his involvement with Explorer. Below are two clips from that interview.

Transcript and Audio Clip 1 (3:00 minutes)

Transcript and Audio Clip 2 (2:30 minutes)

Al Hibbs (1924-2003)

As head of the Research and Analysis Section, Al Hibbs was the systems designer for Explorer 1. Hibbs joined the Jet Propulsion Laboratory, then run by Caltech for the Army, in February 1950. He worked for JPL until his retirement in 1986. In this excerpt from the 1988 interview with Don Bane, Hibbs talks about the international context of the space race culminating in the launch of Explorer 1.

Transcript and Audio Clip (2:30 minutes)