The Satellite Catalog Number (SATCAT, also known as NORAD (North American Aerospace Defense) Catalog Number, NORAD ID, USSPACECOM object number or simply catalog number, among similar variants) is a sequential nine-digit number assigned by the

United States Space Command United States Space Command (USSPACECOM or SPACECOM) is a unified combatant command of the United States Department of Defense, responsible for military operations in outer space, specifically all operations 100 kilometers (62 miles) and grea ...

(USSPACECOM) in the order of launch or discovery to all artificial objects in the orbits of Earth and those that left Earth's orbit. The first catalogued object, catalog number 1, is the Sputnik 1 launch vehicle, with the

Sputnik 1 Sputnik 1 (; see § Etymology) was the first artificial Earth satellite. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957 as part of the Soviet space program. It sent a radio signal back to Earth for ...

satellite having been assigned catalog number 2. __NOTOC__ Objects that fail to orbit or orbit for a short time are not catalogued. The minimum object size in the catalog is in diameter. , the catalog listed 54,200 objects, including 14,102 satellites that had been launched into orbit since 1957 of which 7,043 were still active. 24,146 of the objects were well tracked while 1,850 were lost. In addition USSPACECOM was also tracking 20,900 analyst objects. Analyst objects are variably tracked and in constant flux, so their catalog and element set data are not published. ESA estimated there were about 36,500 pieces of orbiting debris that are large enough for USSPACECOM to track. Permanently catalogued objects are assigned a number from 1 to 69,999 or above 99,999. Space-Track is expected to start publishing objects greater than 99,999 in 2020 starting with debris discovered by

Space Fence The ''Space Fence'' is a second-generation space surveillance system operated by the United States Space Force in order to track artificial satellites and space debris in Earth orbit. Contracts were issued for development and construction in 2 ...

. Space Command shares the catalog vi
space-track.org
which is maintained by the

18th Space Defense Squadron The 18th Space Defense Squadron (18 SDS) is a United States Space Force Space Domain Awareness unit located at Vandenberg Space Force Base, California. The 18th SDS is tasked with executing command and control of the space surveillance networ ...

(18 SDS).

History

Initially, the catalog was maintained by

NORAD North American Aerospace Defense Command (NORAD ), known until March 1981 as the North American Air Defense Command, is a combined organization of the United States and Canada that provides aerospace warning, air sovereignty, and protection ...

. From 1985 onwards, USSPACECOM was tasked to detect, track, identify, and maintain a catalog of all human-made objects in Earth orbit. In 2002, USSPACECOM was disestablished and merged with the

United States Strategic Command United States Strategic Command (USSTRATCOM) is one of the eleven unified combatant commands in the United States Department of Defense. Headquartered at Offutt Air Force Base, Nebraska, USSTRATCOM is responsible for strategic nuclear deter ...

(USSTRATCOM). However, USSPACECOM was reestablished in 2019. Before 2020, the catalog number was limited to five digits due to the TLE format limitation. In 2020, Space-Track started to provide data in CCSDS OMM (Orbit Mean-Elements Message) format, which increased the maximum catalog number to 999,999,999.

References

{{reflist

External links

* The catalog
Space-Track.org

CelesTrak Satellite Catalog
(a partial copy of Space-Track.org catalog) Identifiers Satellites United States Strategic Command

History

See also

References

External links