The SPY-1b on USS Lake Erie successfully tracked and guided an SM-3 to intercept the malfunctioning satellite NROL-21 at an altitude of 153 miles. To achieve the intercept, the SPY-1b had to track the target from a significantly greater distance, but was aided by cueing from other BMD assets.

http://www.mda.mil/system/aegis_one_time_mission.html