Astroconst home page

Current version: v2.3, 11 June 2002

Astroconst is a set of header files in various languages (currently C, Fortran, Perl, Java, IDL and Gnuplot) that provide a variety of useful astrophysical constants without constantly needing to look them up.

The generation of the header files from one data file is automated, so you can add new constants to the data file and generate new header files in all the appropriate languages without needing to fiddle with each header file individually.

Download

RPM: astroconst-2.3-3.noarch.rpm
SRPM: astroconst-2.3-3.src.rpm
TGZ: astroconst-2.3.tar.gz

For full usage notes, please see the README file.

If you think there are vitally-important constants that are missing, you can add them yourself using the astroconst.dat file and generate.pl utility, but also email me and let me know -- I may add them to the master data file.

License

Astroconst is completely free, both as in speech and as in beer. If you find it useful, just drop me an email and let me know.

Revision History

11 June, 2002, v2.3:

• README file made clearer
• Creation of the astrocalc-mks utility (like astrocalc, but using MKS units)
• Added 'use POSIX' into astrocalc/astrocalc-mks (good for such useful functions as log10, etc...)
• Added the following new constants: mean solar density A_dsun, mean Earth density A_dearth, solar surface gravity A_gsun, Earth surface gravity A_gearth, solar V magnitude A_Vsun, solar absolute V magnitude A_MVsun, characteristic impedance of the vacuum A_Z0, permittivity of free space A_eps0, permeability of free space A_mu0, lunar radius A_rmoon, lunar mass A_mmoon, lunar orbital semi-major axis A_amoon, and lunar orbital eccentricity A_emoon.

19 December, 2000, v2.2:

• Fixed value of Thompson cross-section A_sigmaT
• Improved precision of parsec A_pc
• Added CMB temperature A_TCMB, classical electron radius A_re, Bohr radius A_a0, and Wien displacement law constant A_Wien

26 September, 2000, v2.1:

• Added support for Gnuplot, both old versions (3.6 and earlier) and recent versions (3.7 and later)

19 March, 2000, v2.0:

• Added support for IDL and Java.
• Created README file with much better documentation.
• Added the radiation density constant A_arad.
• Created sample programs in all languages on how to use Astroconst in both CGS and MKS mode.
• Fixed description of Hubble time A_tH.

10 March, 2000, v1.3a:

• Added the Stefan-Boltzmann constant A_sigma.

6 March 2000, v1.3:

• Fortran version now uses PARAMETER instead of #define (which can cause expansions to extend beyond the end of the part of the line that Fortran compilers deign to read).
• Included astrocalc utility.

9 Feb 2000, v1.2:

• v1.1 broke perl version - fixed. Added A_pi and A_exp.

21 Jan 2000, v1.1:

• Modified generate.pl to not redefine CGS if it's already defined.

19 Jan 2000, v1.0:

• Astroconst is released to the world.

Disclaimer

The Astroconst values have been gleaned from a variety of sources, and have quite different precisions depending both on the known precision of the value in question, and in some cases on the precision of the source I found it from. These values are not guaranteed to be correct. Astroconst is not certified for any use whatsoever. If your rocket crashes because the precision of the lunar orbital eccentricity isn't high enough, that's too bad.

Last modified: 16h23 CEST, 26 June 2002
Jeremy Bailin