The U.S. Missile Defense Agency's (MDA) Space Tracking and Surveillance System (STSS) Demonstration satellites kept an unblinking watch on a boosting missile during an Airborne Laser Test Bed (ALTB) exercise off the Central California coast Sept. 1, 2010. The STSS satellites were built by Northrop Grumman and Raytheon.

The STSS Demonstration satellites faced a different set of challenges than previously seen because of quick timelines associated with the target, according to Gabe Watson, vice president of missile defense and missile warning programs for Northrop Grumman's Aerospace Systems sector.

"STSS generated a track with the acquisition sensor and autonomously passed the track to the multi-band track sensor for the first time against a missile target," Watson said. "The system performed very well, without operator control, and provided high-quality track data to the ground station."

He noted that the STSS track sensor was cued significantly faster than in previous tests, which was required with this scenario.

"These demonstration satellites employ high-performance infrared sensors with on-board processing that are able to exploit all the advantages of space for precision missile tracking," Watson said.

The Missile Defense Agency (MDA) is pursuing the STSS Demonstration program as a space-based sensor component of the Ballistic Missile Defense System (BMDS). Data from the STSS satellites supports development of a future operational satellite constellation for the BMDS.