United States Space Surveillance Network

The United States Space Surveillance Network detects, tracks, catalogs and identifies artificial objects orbiting Earth, including active and inactive satellites, spent rocket bodies and fragmentation debris. It falls under United States Space Command and is operated by the United States Space Force, and its functions include predicting when and where a decaying object will re-enter the atmosphere, preventing a returning object from triggering a false missile attack alarm, tracking the present and future positions of objects in orbit, detecting new objects, and maintaining a running catalog of artificial space objects.