About us
SOFA operates under the auspices of the International Astronomical Union (IAU) to provide algorithms and software for use in astronomical computing. The initiative is managed by an international panel, the SOFA Board, appointed through IAU Division A. The Board obtains the latest IAU-approved models and theories from the fundamental-astronomy community, implements them as computer code and checks them for accuracy. SOFA works closely with all the Commissions of the Division and with the International Earth Rotation and Reference Systems Service (IERS).
The SOFA Collection consists of two libraries of routines, one coded in Fortran 77 the other in ANSI C. There is a suite of vector/matrix routines and various utilities that underpin the astronomy algorithms, which include routines for the following:
Astrometry
Calendars
Time Scales
Ecliptic Coordinates
Earth Rotation and Sidereal Time
Ephemerides (medium precision)
Fundamental Arguments
Galactic Coordinates
Geocentric/Geodetic Transformations
Precession, Nutation and Polar Motion
Star Catalog Conversion
The link for the current Fortran 77 and ANSI C software gives information on how to obtain it and instructions on its use. Also provided are two validation programs — one for each language. Guides with examples for many of the SOFA routines can be found in the various Cookbooks.
Access to the archive of all previous releases may be obtained from SOFA's software archive. A selection of reports and papers from the IAU SOFA initiative is also available.
IAU Standards of Fundamental Astronomy Board
Acknowledgements
The SOFA Board gratefully acknowledges the support it receives from the institutions and funding bodies of its members. The Board also acknowledges the provision of this web site by HM Nautical Almanac Office (HMNAO), part of the UK Hydrographic Office.
Current members
John Bangert — United States Naval Observatory (retired)
Steven Bell — His Majesty's Nautical Almanac Office (Webmaster)
Maria Davis — United States Naval Observatory (IERS)
Mickaël Gastineau — Paris Observatory, IMCCE
Catherine Hohenkerk — His Majesty's Nautical Almanac Office (former Chair, retired)
Li Jinling — Shanghai Astronomical Observatory
Zinovy Malkin — Pulkovo Observatory, St Petersburg
Wendy Puatua — United States Naval Observatory
Scott Ransom — National Radio Astronomy Observatory
Nick Stamatakos — United States Naval Observatory
Patrick Wallace — RAL Space (retired)
Toni Wilmot — His Majesty's Nautical Almanac Office (Chair)
The email address for the SOFA Board Chair is toni.wilmot@ukho.gov.uk.
Past members
Wim Brouw — University of Groningen
Mark Calabretta — Australia Telescope National Facility
Nicole Capitaine — Paris Observatory
William Folkner — Jet Propulsion Laboratory
Anne-Marie Gontier — Paris Observatory
George Hobbs — Australia Telescope National Facility
George Kaplan — United States Naval Observatory
Brian Luzum — United States Naval Observatory
Dennis McCarthy — United States Naval Observatory
Skip Newhall — Jet Propulsion Laboratory
Jeffrey Percival — University of Wisconsin
Jin Wen-Jing— Shanghai Astronomical Observatory