Space Force operated, 30+ ground-based radars and optical telescopes worldwide, plus 6 satellites in orbit. , the catalog built using SSN data listed 44,336 objects including 8,558 satellites launched into orbit since 1957. 17,480 of them were actively tracked while 1,335 were lost. The rest have re-entered Earth's turbulent atmosphere and disintegrated, or survived re-entry and impacted the Earth. The SSN typically tracks space objects which are 10 centimeters in diameter (baseball size) or larger. The Space Surveillance Network has numerous sensors that provide data. They are separated in three categories: dedicated sensors, collateral sensors and auxiliary sensors. Both the dedicated and collateral sensors are operated by the USSPACECOM, but while the former have a primary objective to acquire SSN data, the latter obtain SSN data as a secondary objective. The auxiliary sensors are not operated by the USSPACECOM and usually perform space surveillance collaterally. Additionally sensors are classified as Near-Earth (NE) tracking - observing satellites, space debris and other objects in lower orbits, or Deep Space (DS) - generally for asteroids and comets. Dedicated sensors Ground-based Electro-Optical Deep Space Surveillance (GEODSS) sites Space Surveillance Telescope (SST) MOSS - an Electro-Optical (E-O) surveillance system located at the Moron Air Base, Spain GLOBUS II radar AN/FPS-85 Space Track Radar AN/FPS-133 Air Force Space Surveillance System, also known as the Space Fence and its replacement Space Fence Midcourse Space Experiment (MSX) / Space Based Visible (SBV) satellites Collateral sensors Maui Space Surveillance System (MSSS) and Advanced Electro-Optical System (AEOS) telescope, co-located with a GEODSS station in Maui, Hawaii Haystack Ultrawideband Satellite Imaging Radar (HUSIR), Haystack Auxiliary Radar (HAX) and Millstone Hill Radar ALTAIR and ALCOR radars at the Ronald Reagan Ballistic Missile Defense Test Site, Kwajalein Atoll Ascension Range Radar, locate at the Eastern Spacelift Range Ground-Based Radar Prototype (GBR-P), located Ronald Reagan Ballistic Missile Defense Test Site, Kwajalein Atoll Auxiliary sensors Solid State Phased Array Radar System (SSPARS) / AN/FPS-132 Upgraded Early Warning Radar (UEWR) system of system, deployed at multiple sites AN/FPS-108 Cobra Dane AN/FPQ-16 Perimeter Acquisition Radar Characterization System (PARCS) Ground-based Electro-Optical Deep Space Surveillance Ground-based Electro-Optical Deep Space Surveillance, or GEODSS, is an optical system that uses telescopes, low-light level TV cameras, and computers. It replaced an older system of six 20 inch (half meter) Baker-Nunn cameras which used photographic film. There are three operational GEODSS sites that report to the 20th Space Control Squadron: Socorro, New Mexico