AST: A library for modelling and manipulating coordinate systems

TL;DR

AST is a mature, object-oriented library that offers extensive tools for defining, attaching, and interpreting coordinate systems in astronomical data, supporting formats like FITS-WCS.

Contribution

It describes the data model of the AST library, which has been in use for over 17 years, aiding future development of coordinate system tools.

Findings

Supports a wide range of coordinate formats

Has been in active use for over 17 years

Provides comprehensive facilities for coordinate manipulation

Abstract

In view of increased interest in object-oriented systems for describing coordinate information, we present a description of the data model used by the Starlink AST library. AST provides a comprehensive range of facilities for attaching world co-ordinate systems to astronomical data, and for retrieving and interpreting that information in a variety of formats, including FITS-WCS. AST is a mature system that has been in use for more than 17 years, and may consequently be useful as a means of informing development of similar systems in the future.