On June 21, 2012, the two Space Tracking and Surveillance System Demonstrators (STSS-D) satellites marked their 1,000th day on orbit. The two Missile Defense Agency satellites were launched into low earth orbit on a NASA Delta II launch vehicle from Cape Canaveral, Fla. on Sept. 25, 2009. Both satellites are operating nominally on-orbit under the control of the Missile Defense Space Development Center at Schriever Air Force Base, Colo., and continue to deliver an operational availability rate of over 99 percent.

STSS-D has performed a remarkable series of 'firsts' in the areas of space-based missile tracking, data collection, and integration, providing risk reduction for future Ballistic Missile Defense System (BMDS) programs. The STSS-D satellites participated in numerous Missile Defense Agency flight tests since launch, tracking ballistic missiles through all phases of flight and demonstrating the viability of space based remote networked sensors to deliver fire control quality tracks to BMDS weapons systems.

In addition to precision ballistic missile tracking, STSS-D is tasked to fully leverage its unique sensor capabilities to collect data across the broad range of missions to include tracking of space launches, on-orbit satellites, satellite re-entries, and collecting of scientific background and scene data on space and terrestrial environments. During the last two years, improvements in mission planning, spacecraft and payload software, ground automation, and power management have allowed a dramatic increase in STSS-D data collection workload. Since January 2012, STSS-D has conducted over 1200 collections, an average of seven per day during round-the-clock operations.

STSS-D has laid a solid foundation and provided risk reduction for the Precision Tracking Space System (PTSS), the follow-on operational missile tracking system which will provide low-earth orbit missile tracking through all phases of flight, delivering accurate and repeatable fire control quality tracking to the BMDS. STSS-D data integration with the BMDS has also demonstrated the viability of networked sensors supporting the Aegis Launch-on Remote capability to defend larger areas with earlier interceptor launch.