Ground Based Electro-Optical Deep Space Surveillance

Definition
The Ground-Based Electro-Optical Deep Space Surveillance (GEODSS) system plays a vital role in tracking deep space objects. More than 2,500 objects, including geostationary communication satellites, are in deep space orbits varying in altitude from 10,000 to 45,000 kilometers from earth.

Approximately 25,000 known man-made objects orbit the earth. These objects range from active payloads, such as weather monitoring satellites or Global Positioning System satellites, to "space junk” such as rocket bodies from previous satellite launches or debris from past satellite breakups.

The 21st Space Wing is responsible for tracking all man-made objects in orbit. The 21 SW receives [[positional tracking data, known as metric observations, from the Space Surveillance Network (SSN) which is comprised of optical and radar sensors throughout the world. This enables the 21 SW to maintain accurate data on many man-made objects currently in orbit.

There are three 21 SW operational GEODSS sites in the SSN located in the U.S. and U.S. Indo-Pacific Command.