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CosmicCalculator - estimate cosmological values


astcosmiccal [OPTION...]


CosmicCalculator is part of GNU Astronomy Utilities 0.8. CosmicCalculator will do cosmological calculations. If no redshfit is specified, it will only print the main input parameters. If only a redshift is given, it will print a table of all calculations. If any of the single row calculations are requested, only their values will be printed with a single space between each.

For more information, please run any of the following commands. In particular the second contains a very comprehensive explanation of CosmicCalculator's invocation: expected input(s), output(s), and a full description of all the options.

All options and their values:
$ astcosmiccal -P
Inputs/Outputs and options:
$ info astcosmiccal
Full section in manual/book:
$ info CosmicCalculator
Full Gnuastro manual/book:
$ info gnuastro

If you couldn't find your answer in the manual, you can get direct help from experienced Gnuastro users and developers. For more information, please run:

$ info help-gnuastro

CosmicCalculator options:

-H, --H0=FLT
Current expansion rate (Hubble constant).
-l, --olambda=FLT
Current cosmological cst. dens. per crit. dens.
-m, --omatter=FLT
Current matter density per critical density.
-r, --oradiation=FLT
Current radiation density per critical density.
-z, --redshift=FLT
Redshift of interest.
Specific calculations
-a, --absmagconv
Conversion to absolute magnitude (no unit).
-A, --angulardimdist
Angular diameter distance (Mpc).
-b, --lookbacktime
Look back time to z (Ga: Giga Annum).
-c, --criticaldensity
Critical density at z (g/cm^3).
-C, --criticaldensitynow
Critical density now (g/cm^3).
-d, --properdistance
Proper distance to z (Mpc).
-g, --age
Age of universe at z (Ga: Giga Annum).
-G, --agenow
Age of universe now (Ga: Giga Annum).
-L, --luminositydist
Luminosity distance to z (Mpc).
-s, --arcsectandist
Tangential dist. covered by 1arcsec at z (kpc).
-u, --distancemodulus
Distance modulus at z (no units).
-v, --volume
Comoving volume (4pi str) to z (Mpc^3).
Operating modes:
-?, --help
give this help list
BibTeX citation for this program.
Read configuration file STR immediately.
Do not parse any more configuration files.
Only run if the program version is STR.
-P, --printparams
Print parameter values to be used and abort.
-S, --setdirconf
Set default values for this directory and abort.
give a short usage message
-U, --setusrconf
Set default values for this user and abort.
-V, --version
print program version

Mandatory or optional arguments to long options are also mandatory or optional for any corresponding short options.

GNU Astronomy Utilities home page:


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Copyright © 2015-2018, Free Software Foundation, Inc. License GPLv3+: GNU General public license version 3 or later.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.

Written/developed by Mohammad Akhlaghi


The full documentation for CosmicCalculator is maintained as a Texinfo manual. If the info and CosmicCalculator programs are properly installed at your site, the command
info CosmicCalculator

should give you access to the complete manual.

December 2018 GNU Astronomy Utilities 0.8