Space Surveillance Network

Overview
The U.S. Space Surveillance Network (SSN) detects, tracks, catalogs and identifies artificial objects orbiting Earth, i.e. active/inactive satellites, spent rocket bodies, or fragmentation debris. The system is the responsibility of the Joint Functional Component Command for Space, part of the United States Strategic Command (USSTRATCOM).

Space surveillance accomplishes the following:


 * Predict when and where a decaying space object will re-enter the Earth's atmosphere;
 * Prevent a returning space object, which to radar looks like a missile, from triggering a false alarm in missile-attack warning sensors of the U.S. and other countries;
 * Chart the present position of space objects and plot their anticipated orbital paths;
 * Detect new man-made objects in space;
 * Correctly map objects travelling in the earth's orbit;
 * Produce a running catalog of man-made space objects;
 * Determine which country owns a re-entering space object;
 * Inform NASA whether or not objects may interfere with satellites and International Space Station orbits.

"United States Space Surveillance Network"