Exoatmospheric Reentry-vehicle Interceptor Subsystem

The Exoatmospheric Reentry-vehicle Interceptor Subsystem, or ERIS, program, was a component of the United States' Strategic Defense Initiative during the Cold War.

ERIS was to be complemented by another ABM system, High Endoatmospheric Defense Interceptor (HEDI), which destroyed enemy missiles in the atmosphere.

[1] ERIS used a Kinetic Kill Vehicle (KKV), which destroyed its target by force of impact, not by an explosive charge.

[1] The ERIS received data on its target's location from satellites and radar until the KKV separated from the delivery vehicle.

The miss resulted from the KKV's guidance system taking too long to distinguish between the mock ICBM and the decoy balloon.

Despite the miss, the test was declared a success, as the KKV's guidance system was able to correctly identify the mock ICBM, albeit a bit late.

After the collapse of the Soviet Union, and effective end of the Cold War, the Strategic Defense Initiative was reorganized.