COSMICCALCULATOR(1)

💫 COSMICCALCULATOR(1) — User Commands 💫

okay bestie, buckle up, this is CosmicCalculator, one of the little legends from GNU Astronomy Utilities 0.24, and she's here to do your cosmological calculations for you. no cap.

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✨ NAME ✨

CosmicCalculator — estimate cosmological values 🦋

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✨ SYNOPSIS ✨

astcosmiccal [OPTION...]

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✨ DESCRIPTION ✨

so like, CosmicCalculator is part of GNU Astronomy Utilities 0.24 💖 and she does cosmological calculations. periodt.

here's the tea on how she behaves:

• if no redshift is specified, she will only print the main input parameters.
• if only a redshift is given, she will print a table of all the calculations.
• if any of the single row calculations are requested, only their values will be printed, with a single space between each one. no frills, just numbers.

for more info, pls run any of these commands. and like, the second one is the main character here — it contains a very comprehensive explanation of CosmicCalculator's invocation: expected input(s), output(s), and a full description of all the options. iykyk 👑

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

and if you couldn't find your answer in the manual, you can get direct help from experienced Gnuastro users and developers. for more info, pls run:

$ info help-gnuastro

CosmicCalculator options 👇

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✨ OPTIONS ✨

🌸 Input:

• -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.
• -O, --obsline=STR,FLT — redshift from line and observed wavelength. 🔭
• -r, --oradiation=FLT — current radiation density per critical density.
• -y, --velocity=FLT — velocity of interest in km/s. 🏃‍♀️
• -z, --redshift=FLT — redshift of interest.

🌈 Basic cosmology calculations

• -a, --absmagconv — conversion to absolute magnitude (no unit).
• -A, --angulardiamdist — 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). 📏
• -e, --usedredshift — used redshift in this run.
• -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. for 1arcsec at z (physical kpc).
• -u, --distancemodulus — distance modulus at z (no units).
• -v, --volume — comoving volume (4pi str) to z (Mpc^3). 🫧
• -Y, --usedvelocity — used velocity (in km/s) for this run.

🧚 Spectral lines

• -i, --lineatz=STR/FLT — wavelength of line (name or wavelength) at z.
• --lineunit=STR — unit ('angstrom', 'nm', 'microm' or 'm').
• --listlines — list pre-defined lines at rest frame.
• --listlinesatz — list pre-defined lines at the given redshift.

👑 Operating modes:

• -?, --help — give this help list
• --checkconfig — list all config files and variables read.
• --cite — BibTeX citation for this program.
• --config=STR — read configuration file STR immediately.
• --config-prefix=STR — custom prefix of option names config files.
• --lastconfig — do not parse any more configuration files.
• --minmapsize=INT — min. bytes to avoid RAM automatically.
• --onlyversion=STR — only run if the program version is STR.
• -P, --printparams — print parameter values to be used and abort.
• --quietmmap — don't print mmap'd file's name and size.
• -S, --setdirconf — set default values for this directory and abort.
• --usage — give a short usage message
• -U, --setusrconf — set default values for this user and abort.
• -V, --version — print program version

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okay important note bestie: mandatory or optional arguments to long options are also mandatory or optional for any corresponding short options. 💅

GNU Astronomy Utilities home page: http://www.gnu.org/software/gnuastro/

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🐛 REPORTING BUGS 🐛

found a bug? not cute. report it to bug-gnuastro@gnu.org 🙈

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⚖️ COPYRIGHT ⚖️

Copyright © 2015-2025 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 🌟

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👀 SEE ALSO 👀

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. 🎀

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and that's the whole vibe, bestie 🦋 this was GNU Astronomy Utilities 0.24, dated November 2025 — slay, go compute some universe stuff 💖✨