The latest version of the General Astrodynamics Library has been released. Version 0.2.0 can be downloaded from:
http://homepage.mac.com/pclwillmott/GAL/Download.html
New features in this release include:
SGP4 orbit propagator based upon David Vallado's combined SGP4/SDP4 model.
Additional time conversion routines
ITRF-GCRF-ITRF position and velocity reference frame transforms based upon IAU2000A/B & IAU2006A resolutions.
Gravity model support added
Ellipsoid model support added.
The General Astrodynamics Library (GAL) is a numerical library for C and C++ programmers. It is free software under the GNU General Public License.
The library provides a wide range of astrodynamical routines such as ephemerides, earth orientation, and orbit propagation. There are over 210 functions in total with an extensive test suite.
Next up numerical orbit propagation.