About this ArticleMAST Staff - 2023 Mar 28
New documentation is available for the catalogs hosted by MAST. The MAST Catalogs Guide includes a summary of the collections you can access using the catalog web service API (application programming interface). You’ll also find examples of catalog queries to get you started using the API.
The Guide Star Catalog (GSC) was initially constructed to support the pointing and target acquisition for the Hubble Space Telescope. It has since been adopted for numerous other purposes; for example, observation planning, the preparation of finding charts, and the operation of ground-based telescopes, as well as space telescopes like the James Webb Space Telescope and Roman Space Telescope. The Guide Star Catalog Manual documents the origin and evolution of the GSC, key details about its data structures, and version differences. The GSC manual also includes detailed descriptions of the table fields, which are essential for effectively using the catalog.