Brilliant Pebbles was a proposed American ballistic missile defense system (BMD) as envisaged by Edward Teller and Lowell Wood of Lawrence Livermore National Laboratories, Livermore, California.

The idea was to place thousands of small missiles (Brilliant Pebbles) into orbit so that hundreds would be in place above the Soviet Union at any one time. In the event of a Soviet ICBM launch, the Pebbles, using infrared imaging, would detect and collide with the missiles. The Pebbles would collide with the missiles before they MIRVed (released several independent missiles from one ICBM), thus destroying several warheads at one blow.

After much study the program was ordered into production in 1991. After modifications were put into effect to adjust to a changing Soviet Union/Russia, the program's cost, at some 55 billion dollars, was considered excessive, and the program was ultimately abandoned in 1993.

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