Between 1955 and 1959, NRL conducted the first American satellite program called Vanguard. The program was initiated to represent the United States in the International Geophysical Year (IGY). IGY was a cooperative international scientific effort to study the physical properties of Earth. The nation's leaders in science decided to participate in the IGY by placing an artificial satellite in orbit. Following this decision, a competition was held to determine which U.S. government agency would build and launch the satellite. The plan submitted by NRL was selected due, in part, to its success with the Viking Program. NRL's pioneering task was to design, build, launch, place in earth orbit, and track an artificial satellite carrying a scientific experiment.

Vanguard I launch

The Vanguard I is launched from Cape Canaveral, March 17, 1958.

In 1957, because suitable satellite-launching facilities were not available, NRL constructed the first complete satellite-launching facility at Cape Canaveral, Florida. Central control of this facility was maintained at the main NRL site in Washington, DC. Critical functions involved in attaining orbit had to be performed many hundreds of miles from the launch pad. NRL had developed in 1956 the first satellite-tracking system, called Mini track, which provided the first down-range instrumentation for determining the orbit of a satellite. This system evolved from NRL's work on phase comparison and angle tracking and used a series of fan-shaped, vertical antenna beams.

The Vanguard I satellite was successfully launched into earth orbit on March 17, 1958. Vanguard I achieved the highest altitude of any man-made vehicle to that time and established beyond doubt geologists' suspicions that Earth is pear shaped. It carried two radios and a temperature sensor and was the first orbiting vehicle to be powered by solar energy. Photovoltaic silicon solar cells provided the electrical power to the 6.4-inch, 3.5-pound satellite until its experiments and transmitter fell silent in 1964. Vanguard I orbits Earth today as the oldest man-made satellite and will remain in orbit well into the 22nd century.

Vanguard II, launched on February 17, 1959, was the first satellite designed to observe and record the cloud cover of the earth. It was a forerunner of the television infrared observation satellites (TIROS). Vanguard II was also the first full-scale Vanguard (20-inch diameter sphere, 21 pounds) to be launched, and it is also still in orbit. The scientific experiments flown on the Vanguard satellites increased scientific knowledge of space and opened the way for more sophisticated experiments. Vanguard was the prototype for much of what became the U.S. space program.

When the National Aeronautics and Space Administration (NASA) was established on July 29, 1958, the NRL Vanguard group, a total of approximately 200 scientists and engineers, became the core of its spaceflight activities. The group remained housed at NRL until the new facilities at the Goddard Space Flight Center at Beltsville, Maryland, became available in September 1960.