U.S. space-based missile alert system moves forward

The United States' futuristic missile alert system operating from outer space moved forward with Lockheed Martin's delivery of the third "highly elliptical earth orbit" satellite payload system.
A further fourth HEO is due to complete the USAF order, which will be yet another step toward initiating the Space Based Infrared System. SBIRS is designed to give the U.S. military a global capability to detect and monitor a ballistic missile launch from anywhere.
spacedaily