Raytheon Co. has delivered the second of two advanced infrared sensor payloads to Northrop Grumman Space Technology for the missile-warning Space Tracking & Surveillance System Block 6 program, Raytheon announced Feb. 9.

Block 6 satellites will demonstrate the key functions of a space-based sensor within the Ballistic Missile Defense System, passing missile tracking data to missile defense interceptors. The payloads will be integrated aboard two satellites as part of an on-orbit missile detection experiment. Raytheon delivered the first payload in March 2006.