GCAT: General Catalog of Artificial Space Objects

Jonathan C. McDowell

Object Catalogs

Main Object Catalogs

GCAT Release 1.5.5 (2024 May 5) | Data Update 2024 Oct 09

Object Catalogs Organization

The General Catalog of Artificial Space Objects has eleven object catalogs and five payload catalogs, each with a different role. The object catalogs, while containing different groups of objects, all have the same format - from a relational database point of view, they could be concatenated into a single table without loss of information. The same is true of the payload catalogs. Nevertheless, I find it clearer to keep the catalogs separated.


The diagram below shows the interrelations between the different catalogs. Each payload catalog is paired with an object catalog, but not all the object catalogs have payload catalogs. The various catalogs are summarized in the table below. I then discuss each catalog in general terms, and finally explain the catalog columns.



Object CatalogFull nameObject prefixDescription
Primary Orbital Object Catalogs
satcatStandard Satellite CatalogSObjects from the US Satellite Catalog
auxcatAuxiliary Satellite CatalogAObjects omitted from the US catalog
ftocatFailed Satellite CatalogFObjects which failed to reach orbit
Supporting Catalogs
lcatLow Altitude (Endoatmospheric) CatalogLObjects whose apogee was less than 80 km
rcatSuborbital Rocket (Exoatmospheric) CatalogRObjects whose apogee was 80 km or more
Temporary Catalogs
tmpcatTemporary CatalogTObjects expected to receive an S catalog number soon
csocatComplementary Space Object CatalogCObserved objects whose mapping to S is uncertain
Event Catalogs
ecatEvent CatalogLater phases in history for objects in primary catalogs.
deepcatDeep Space CatalogDObjects which reached more that 150,000 km from Earth
hcocatHeliocentric RegisterDObjects in heliocentric orbit
lprcatLunar and Planetary RegisterDObjects in sphere of influence of other worlds
Payload Catalogs
psatcatPayload catalogSPayload data for payloads in satcat
pauxcatPayload catalogAPayload data for payloads in auxcat
pftocatPayload catalogFPayload data for payloads in ftocat
plcatPayload catalogLPayload data for payloads in lcat
prcatPayload catalogRPayload data for payloads in lcat
pdeepcatPayload catalogDPayload data for payloads in deepcat which are not in other payload cats
Derived Catalogs
currentcatSummary catalogS/AMost recent phase for each S and A object, with latest orbit data