Reference Manual Released

A Reference Manual has been put together. It can be downloaded from the Downloads page.

Version 0.4.0 Released

Version 0.4.0 of the General Astrodynamics Library has been released. It can be downloaded from the project website here:

http://homepage.mac.com/pclwillmott/GAL/index.html

Updates in this release:

Higher precision ephemerides for the Sun, Planets, and Pluto. Implemented using VSOP87. Heliocentric and barycentric routines for position and velocity provided.

Support added for classical Keplerian models, circular, ellipticals, parabolic, and hyperbolic orbits and trajectories supported. Keplerian propagation implemented using the Universal formulation.

Release includes some additional support files, and minor updates.

Work continues with the atmosphere, and remaining force models.

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 250 functions in total with an extensive test suite.

Paul Willmott, VP9MU
AMSAT-BDA

Version 0.3.0 Released

Version 0.3.0 of the General Astrodynamics Library has been released. It can be downloaded from the project website here:

http://homepage.mac.com/pclwillmott/GAL/index.html

Updates in this release:

ODE Integrator sub-library created.

Lunar position and velocity routine added to ephemerides sub-library. Routine implements LUNAR SOLUTION ELP version ELP/MPP02

Solar position and velocity routine added to ephemerides sub-library.

Acceleration from spherical harmonics routine added to gravity sub-library.

Many routines updated for internal compatibilty with the upcoming official IAU SOFA C library. R-matrices have had indicies reversed compared to GAL 0.2 and earlier.

Work will now be started on the classical keplerian models, and atmosphere models.

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 225 functions in total with an extensive test suite.

Paul Willmott, VP9MU
AMSAT-BDA

Include File Issues

A few problems crept into the version 0.2.0 release. It appears that some include file links were missing, and that a couple of filenames were not in the correct case. These have hopefully been corrected. A new distribution has been posted (the filenames are the same but the dates have been changed).

If you are having problems compiling, and it bombs in the "gravity" sub-library then re-download the distribution and try again.

Please let us know if this does not sort out the problem.

Version 0.2.0 Released

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.

Next up numerical orbit propagation.

Zip ...

A zipped version of the libgal-0.1.0 distribution has been added to the downloads page to help Windows users.

Version 0.1.0 Released

Version 0.1.0 of the General Astrodynamics Library has been released on the web site. This release contains the fundamental astronomy routines that were translated from the IAU's SOFA FORTRAN library.

The distribution can be downloaded from here:

http://homepage.mac.com/pclwillmott/GAL/index.html

The next phase will be the addition of support routines for the orbit propagators.