GCAT: General Catalog of Artificial Space Objects

Jonathan C. McDowell


GCAT Release 1.1.10 (2021 Apr 4) | Data Update 2021 May 07

The General Catalog of Artificial Space Objects (GCAT) makes public the full satellite database that underlies Jonathan's Space Report

The diagram below indicates the general structure of the database, which reflects the data model of the information it describes.

An artificial space object (for short, in future simply `object') a satellite or spacecraft (active payload, rocket stage, discarded component, piece of debris) outside the Earth's lower atmosphere. At a given time it can be in one of the following object states:

Each time the object transitions to another state (undocks, is attached to something, reenters, changes which body it is orbiting, etc.) marks the beginning or end of a phase. Most objects in GCAT have only a single phase - they separate from an object (launch vehicle) and then are either still in free flight or have reentered. However, some objects go through many phases.

The main object catalogs define and list the first phase of each object. Objects with more than one phase have their subsequent phases listed as entries in the event object catalogs. A subset of objects are considered payloads and have additional data in the payload catalogs.

Each object (with rare exceptions) is associated with a single launch, described in the launch lists. Each launch may be associated with many objects. The launch lists are the same as those in the already-published LVDB.

Each launch is associated with a launch vehicle and a launch origin (generalization of launch site), and both launches and objects are associated with organizations of several kinds (countries, owners, manufacturers). These associations are expressed by strings which link the launch and object catalogs with the supporting tables.

Figure: (1) Overall structure of GCAT. (2) Detailed structure of the object catalogs.

The supporting tables and the launch lists were published as GCAT release 1.0.2 in Aug 2020. Pre-release versions have been public for a decade as part of the Launch Vehicle Database (LVDB). Release 1.1.0 is the first complete, formally versioned and documented release to include the object catalogs.

For each payload, there is also a payload narrative and a payload event log. However, these are considerably further from being ready for publication, so don't hold your breath.

Citing GCAT

GCAT is released under the Creative Commons CC-BY licence. You are free to use the data in GCAT as long as you include a citation to it. A suitable short citation is 'data from GCAT (J. McDowell, planet4589.org/space/gcat)'. A full citation is

McDowell, Jonathan C., 2020. General Catalog of Artificial Space Objects,
  Release 1.1.10 , https://planet4589.org/space/gcat