SOLRAD

[2] As a result, the United States Air Force and the Navy found themselves in the awkward position of wanting to orbit spy satellites but not reveal their nature to potential enemies.

Just as the Air Force elected to pair their capsule film recovery satellites with biological payloads under the Discoverer program, so did the Navy develop a scientific cover for its GRAB series of radio/radar surveillance (ELINT) satellites.

[3] Thus, the GRAB satellites would be equipped with X-ray sensors such that they could conduct publicly available scientific research while secretly spying on other countries' military installations.

[4] When the National Aeronautics and Space Administration was established on July 29, 1958, most of the NRL Vanguard group's 200 scientists and engineers became the core of NASA's spaceflight activities (though the group remained housed at NRL until the new facilities at the Goddard Space Flight Center in Beltsville, Md.

The first five SOLRADs, launched 1960–1962, were scientific payloads aboard GRAB ELINT satellites, whose primary mission was to monitor foreign radar and communications systems.