The Relay mirror experiment (RME), launched in February 1990, demonstrated critical technologies for space-based relay mirrors that would be used with an SDI
directed-energy weapon system. The experiment validated stabilization, tracking, and pointing concepts and proved that a laser could be relayed from the ground to a 60
cm mirror on an orbiting satellite and back to another ground station with a high degree of accuracy and for extended durations.
With the above statement they must have developed some way of directing the beam?
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