This is the backup for the first Galactic Radiation and Background satellite (GRAB-1), the world's first successful reconnaisance satellite. Built by the Naval Research Laboratory (NRL), GRAB-1 was launched on June 22, 1960, as part of a highly classified program designed to obtain data on Soviet air defense radars for use by the U.S. Strategic Air Command in developing electronic countermeasures and the most effective bomber routes. The satellite also carried instruments to measure solar radiation, part of an unclassified and publicly-acknowledged project dubbed Solrad. Five GRAB satellites were launched from June 1960 to April 1962, but only the first and third reached orbit. The program was declassified by the Navy in 1998, and the NRL donated this artifact in 2002.
Transferred from the Naval Research Laboratory