USA-205
USA-205,[1] also known as Space Tracking and Surveillance System-Advanced Technology Risk Reduction (STSS-ATRR), and previously as Block 2010 Spacecraft Risk Reduction is a satellite formerly operated by the United States Missile Defense Agency.It was launched to demonstrate new technology for missile detection early warning systems (MDEWS).[1] The technology demonstrated on STSS-ATRR was used in the development of the Space Tracking and Surveillance System (STSS) part of the Space-Based Infrared System (SBIRS).[3] Operational and administrative control of the Space Tracking and Surveillance System-Advanced Technology Risk Reduction (STSS-ATRR) satellite was transferred to Air Force Space Command (AFSPC), effective 31 January 2011.In addition to successfully demonstrating required on orbit system performance parameters for a prototype sensor technology, STSS-ATRR conducted Space Situational Awareness and related operations on an as-capable basis.