General Astrodynamics Library

Manual moving to LaTex

2011-11-03T21:34:00.003-03:00

Work continues, ... the documentation has been ported from Word to LaTex. In reviewing the manual it is clear that some upgrades are needed, these will be addressed in version 0.7 as getting a stable 0.6 release is the priority.

Paul, VP9MU

Website is Moving

2011-06-15T18:24:00.002-03:00

As Apple are discontinuing the MobileMe service, the project needs to find a new home, and we have.

The GAL project will now be hosted on the AMSAT-BDA web site.

The new website is being constructed as I type, and when complete the existing Apple site will be decommissioned.

So the new address is:

http://www.amsat-bda.org

The new contact email address for GAL is now:

vp9mu@amsat-bda.org

Cheers
Paul Willmott, VP9MU
AMSAT-BDA

Page redo

2011-04-30T12:12:00.002-03:00

I've updated the download page to reflect that 0.6 [DRAFT] is now the preferred version, even though it is not complete.

Version 0.6 has been updated to reflect the new routines and fixes of the December 1, 2010 SOFA release.

Work continues on bringing the Reference Manual up to date, if you spot any errors in the draft then let me know.

On the coding front we're close to a freeze for this release. The object codes need correcting to match NAIF SPICE values, and some of the older routines need re-formatting. Some of the USTRATCOM routines, including SGP4, will need to be changed as a result of the new quasi-JD UTC dates introduced by SOFA last December.

Anyway after two years it looks like version 0.6 will be fixed, hurrah!

Cheers
Paul

JPL and IMCCE Ephemeris file support added

2010-04-30T18:13:00.003-03:00

The latest DRAFT version of GAL 0.6 has been uploaded to the web site. This includes full support for JPL and IMCCE ephemeris files.

These will be the last new features added to version 0.6, work now continues on updating the documentation and fine-polishing the code.

The current DRAFT is quite stable and feedback from users is requested on this version.

Regards
Paul, VP9MU

GAL Version 0.6.0 pre-release now available

2010-03-08T18:16:00.003-04:00

A pre-release of GAL 0.6.0 is now available on the website. Users should note that there have been many changes to the interfaces of a lot of routines. Users should therefore install this version separatly from their current working code.

New in this version:

Status recording sub-library
Osculating to mean keplerian elements conversion
Gravity model file import
Gravity models now encapsulated inside routines
Fixes for c++ compatibility
Data extracts from USSPACECOM Satellite Situation Report
Lots of general housekeeping

The full version of 0.6.0 will be released once the manual has been updated.

Paul, VP9MU
AMSAT-BDA

Reference Manual v0.5 Released

2009-02-03T14:23:00.002-04:00

The Reference Manual for the General Astrodynamics Library
(GAL) has been updated to include the changes/additions of
version 0.5.0 of the library.

It can be downloaded from the project website here:

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

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 260 functions in total with an
extensive test suite.

Paul Willmott, VP9MU
AMSAT-BDA

Version 0.5.0 Released

2009-01-10T17:13:00.001-04:00

Version 0.5.0 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:

** Additional routines added to Kepler sub-library

** Planetary and Moon rotational elements added

** Reference frame routines for planets other than Earth

** Acceleration due to Solar Radiation Pressure added

** Acceleration due to Atmospheric Drag added

** Sun occulation routine added for satellite eclipses

** Support for Harris-Priester Earth Atmosphere Model

** Mars date and time routines added

** Ellipsoid models for the planets and the Sun added

** Earth satellite rise/set routine added.

The Reference Manual will be updated shortly.

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 260 functions in total with an extensive test suite.

Paul Willmott, VP9MU
AMSAT-BDA

Reference Manual Released

2008-10-27T14:28:00.001-03:00

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

Version 0.4.0 Released

2008-09-21T11:56:00.004-03:00

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

2008-06-23T10:18:00.001-03:00

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

2008-05-14T19:09:00.002-03:00

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

2008-05-13T18:47:00.001-03:00

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 ...

2008-03-19T12:02:00.003-03:00

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

2008-03-19T09:56:00.005-03:00

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.