Flight back-up of the Vanguard 1 satellite built by the Naval Research Laboratory. Vanguard 1 was successfully launched on 17 March 1958, after an initial failure the preceding December. This backup satellite was donated to NASM in December 1975 by the former Vanguard Project Director, Dr. John P. Hagen. The satellite has been exhibited at NASM as well as by the U.S. Information Agency (1976) and at the Kansas Cosmophere and Discovery Center (1982-1985).
This object is on display in Space Science at the Steven F. Udvar-Hazy Center in Chantilly, VA.