Status Report

Digital color codes of stars

By SpaceRef Editor
January 18, 2021
Filed under , ,

Jan-Vincent Harre, René Heller

Publications in astrophysics are nowadays mainly published and read in digitized formats. Astrophysical publications in both research and in popular outreach often use colorful representations of stars to indicate various stellar types, that is, different spectral types or effective temperatures. Computer generated and computer displayed imagery has become an integral part of stellar astrophysics communication. There is, however, no astrophysically motivated standard color palette for illustrative representations of stars and some stars are actually represented in misleading colors. We use pre-computed PHOENIX and TLUSTY stellar model spectra and convolve them with the three standard color matching functions for human color perception between 360nm and 830nm. The color matching functions represent the three sets of receptors in the eye that respond to red, green, and blue light. For a grid of main sequence stars with effective temperatures between 2300K and 55,000K of different metallicities we present the red-blue-green and hexadecimal color codes that can be used for digitized color representations of stars as if seen from space. We find significant deviations between the color codes of stars computed from stellar spectra and from a black body radiator of the same effective temperature. We illustrate the main sequence in the color wheel and demonstrate that there are no yellow, green, cyan, or purple stars. Red dwarf stars (spectral types M0V – M9V) actually look orange to the human eye. Old white dwarfs such as WD1856+534, host to a newly discovered transiting giant planet candidate, occur pale orange to the human eye, not white. Our freely available software can be used to generate color codes for any input spectrum such as those from planets, galaxies, quasars etc.

Comments: 13 pages, 5 figures, accepted by Astronomische Nachrichten / Astronomical Notes

Subjects: Solar and Stellar Astrophysics (astro-ph.SR)

Cite as: arXiv:2101.06254 [astro-ph.SR] (or arXiv:2101.06254v1 [astro-ph.SR] for this version)

Submission history

From: Jan-Vincent Harre 

[v1] Fri, 15 Jan 2021 18:37:52 UTC (8,898 KB)

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