PETERSON AIR FORCE BASE, Colo. (AP) -- An experimental military surveillance satellite that lasted far longer than expected has ended its mission.
The Air Force Space Command said Monday that Tactical Satellite 3 was launched in May 2009 as a one-year experiment but lasted for two years and eight months.
The satellite has dropped out of orbit and burned up in the Earth's atmosphere.
Space Command says the satellite was unique in its ability to recognize types of metal and concrete, and in some cases it could distinguish between human-made and natural materials.
Space Command has its headquarters at Peterson Air Force Base, Colo.