Standards of Fundamental Astronomy

Standards of Fundamental Astronomy
Stable release	2023-10-11 / 2023-10-11
Repository	{{URL|example.com|optional display text}}
Written in	C and Fortran
Engine
Operating system	Cross-platform
Type	Numerical library
License	SOFA Software License
Website	http://www.iausofa.org/

The Standards of Fundamental Astronomy (SOFA) software libraries are a collection of subroutines that implement official International Astronomical Union (IAU) algorithms for astronomical computations.

As of February 2009 they are available in both Fortran and C source code format.

Capabilities

The subroutines in the libraries cover the following areas:

• Calendars
• Time scales
• Earth's rotation and sidereal time
• Ephemerides (limited precision)
• Precession, nutation, polar motion
• Proper motion
• Star catalog conversions
• Astrometric transformations
• Galactic Coordinates

Licensing

As of the February 2009 release, SOFA licensing changed to allow use for any purpose, provided certain requirements are met. Previously, commercial usage was specifically excluded and required written agreement of the SOFA board.

See also

• Naval Observatory Vector Astrometry Subroutines

External links

• SOFA Home Page
• Scholarpedia overview of SOFA
• International Astronomical Union and Working group "Standards of Fundamental Astronomy