Project GRAB First ELINT Satellite Program
Project GRAB mattered because it turned orbit into an invisible listening post. Publicly, SOLRAD studied solar radiation. Secretly, the GRAB payload listened for Soviet air-defense radar pulses that aircraft could not safely collect after the U-2 crisis. The satellite was tiny, simple, and deeply classified, but its effect was enormous: it proved that electronic intelligence could be collected from space, fed data to NRL, NSA, and Strategic Air Command, and established the path from TATTLETALE and CANES into POPPY and the later NRO SIGINT architecture.