MUSE_CREATE_SKY(7)

💫 muse_create_sky — the night sky, but make it a recipe 💫

okay bestie, so this is a muse pipeline recipe — it lives in section 7 of the manual, and honestly? it's giving "look at the empty sky and turn it into a model" energy. no cap. ✨

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🌌 NAME 🌌

muse_create_sky — literally builds a night sky model out of selected pixels from an exposure of empty sky. 🦋

like. you point at nothing (well, mostly nothing), and you get back the sky. iconic behavior fr fr.

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🎀 SYNOPSIS 🎀

esorex muse_create_sky [OPTIONS] FILE.sof

that's it, that's the whole vibe. a .sof file, some options, and we're off. 💅

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✨ DESCRIPTION ✨

so what does this recipe actually do, you ask? 🌸

It creates the continuum and the atmospheric transition line spectra of the night sky. Where does it get them from? From the data in a pixel table(s) that belongs to one exposure of (mostly) empty sky. 🌈

one exposure. mostly empty. and it pulls the sky out of it. main character energy honestly. 👑

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💖 OPTIONS 💖

bestie, there are nine of them. all of them matter. no skipping. let's go one by one, i'll hold your hand. 🫶

• --fraction <float> — This is how much of the image (not counting the ignored part) gets treated as sky. If you handed in a sky mask, the fraction applies to the regions inside the mask. And if you want the whole sky mask used, set this thing to 1. It's a float, and it defaults to 0.75. The full name for the EsoRex configuration file is muse.muse_create_sky.fraction [default = 0.75].
• --ignore <float> — The fraction of the image that gets ignored. Same mask rule as above: if there's an input sky mask, the fraction applies to the regions within the mask. Want the whole sky mask? Set this to 0. It's a float, default 0.05. Full EsoRex config name: muse.muse_create_sky.ignore [default = 0.05].
• --sampling <float> — The spectral sampling of the sky spectrum, in Angstrom. Float, default 0.3125. Full EsoRex config name: muse.muse_create_sky.sampling [default = 0.3125].
• --csampling <float> — The spectral sampling of the continuum spectrum, also in Angstrom. Float, default 0.3125. Full EsoRex config name: muse.muse_create_sky.csampling [default = 0.3125].
• --crsigma <str> — Sigma level clipping for both cube-based and spectrum-based CR rejection. Okay so this one has rules: it has to be a string of two comma-separated floating-point numbers. The first value = the sigma-level rejection for cube-based CR rejection (using "median", see muse_scipost). The second value = the sigma-level for spectrum-based CR cleaning. And here's the cute part: you can switch both off by passing zero or a negative value. It's a string, default ´15.,15.´. Full EsoRex config name: muse.muse_create_sky.crsigma [default = 15.,15.].
• --lambdamin <float> — Cuts off the data below this wavelength, after loading the pixel table(s). Float, default 4000.0. Full EsoRex config name: muse.muse_create_sky.lambdamin [default = 4000.0].
• --lambdamax <float> — Cuts off the data above this wavelength, also after loading the pixel table(s). Float, default 10000.0. Full EsoRex config name: muse.muse_create_sky.lambdamax [default = 10000.0].
• --lambdaref <float> — The reference wavelength used for correcting differential atmospheric refraction. Here's the tea: the R-band (peak wavelength ~7000 Angstrom), which is usually what's used for guiding, sits close to the central wavelength of MUSE — so if you don't know anything else, use 7000.0 Angstrom. And if you pass a value less than zero, that switches DAR correction off. Float, default 7000.0. Full EsoRex config name: muse.muse_create_sky.lambdaref [default = 7000.0].

okay real talk for a sec 🫶 — you can make a configuration file holding all these options plus suitable default values. For the deets on that, go check what esorex --help tells you. no cap.

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🔥 SEE ALSO 🔥

the full documentation for the muse pipeline can be downloaded as a PDF, bestie, right here:

ftp://ftp.eso.org/pub/dfs/pipelines/muse/muse-pipeline-cookbook-2.8.7.pdf

an overview of all the existing ESO pipelines lives at:

https://www.eso.org/sci/software/pipelines/

basic documentation about the EsoRex program itself? that's at the esorex (1) man page. 🌸

and fun fact — you can call the pipelines from python using the python-cpl package. more info at:

https://packages.python.org/python-cpl/index.html

now, the other recipes of the muse pipeline — and yes i'm listing every single one because they're all stars ⭐:

muse_ampl(7), muse_astrometry(7), muse_bias(7), muse_dark(7), muse_exp_align(7), muse_exp_combine(7), muse_flat(7), muse_geometry(7), muse_illum(7), muse_lingain(7), muse_lsf(7), muse_qi_mask(7), muse_scibasic(7), muse_scipost(7), muse_scipost_apply_astrometry(7), muse_scipost_calibrate_flux(7), muse_scipost_combine_pixtables(7), muse_scipost_correct_dar(7), muse_scipost_correct_rv(7), muse_scipost_make_cube(7), muse_scipost_raman(7), muse_scipost_subtract_sky(7), muse_scipost_subtract_sky_simple(7), muse_standard(7), muse_twilight(7), muse_wavecal(7)

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🧚 VERSION 🧚

muse_create_sky 2.8.7

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👑 AUTHOR 👑

Ole Streicher <https://support.eso.org>

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🙈 BUG REPORTS 🙈

please report any problems to <https://support.eso.org>. alternatively, you may send a report to the ESO User Support Department <usd-help@eso.org>.

(they're nice, i promise. don't be shy.)

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📜 LICENSE 📜

this file is part of the MUSE Instrument Pipeline Copyright (C) 2005, 2019 European Southern Observatory

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02111-1307 USA

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💀 and that's the whole page, bestie. go model yourself some sky.

muse_create_sky version 2.8.7, dated 2.8.7, from the MUSE pipeline — mwah, slay, bye. 💖✨🎀🦋🌸💅🫶