File:Alpha Centauri relative sizes.png
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Summary
A comparison of the sizes and colors of the stars in the Alpha Centauri system with the Sun.
File:Alpha Centauri relative sizes.svg is a vector version of this file. It should be used in place of this PNG file when not inferior.
File:Alpha Centauri relative sizes.png → File:Alpha Centauri relative sizes.svg
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David Benbennick made this image on January 29, 2005 with the following Metapost program as stars.mp:
verbatimtex \font\foo=cmss9 at 10pt \foo etex sunrad=0.3in; alpharad = 1.227*sunrad; betarad = 0.865*sunrad; proximarad = 0.145*sunrad; gap = 0.8*sunrad; pair sunpos, alphapos, betapos, proximapos; sunpos = (0 + gap + sunrad, 1.9*sunrad); alphapos = sunpos + (sunrad + gap + alpharad, 0); betapos = alphapos + (alpharad + gap + betarad, 0); proximapos = betapos + (betarad + gap + proximarad, 0); beginfig(1); fill unitsquare xscaled ((xpart proximapos) + proximarad + gap) yscaled (2 * (ypart sunpos)); fill fullcircle scaled (2*sunrad) shifted sunpos withcolor (1,0.960,0.949); % Color is fff1ed label.bot(btex Sun etex, sunpos - (0, sunrad)) withcolor white; fill fullcircle scaled (2*alpharad) shifted alphapos withcolor (1,0.960,0.949); label.bot(btex $\alpha$ Centauri A etex, alphapos - (0, alpharad)) withcolor white; fill fullcircle scaled (2*betarad) shifted betapos withcolor (1,0.878,0.737); % ffe0bc label.bot(btex $\alpha$ Centauri B etex, betapos - (0, betarad)) withcolor white; fill fullcircle scaled (2*proximarad) shifted proximapos withcolor (1,0.752,0.411); % ffcc6f label.bot(btex Proxima etex, proximapos - (0, proximarad)) withcolor white; endfig; end;
And I had the following TeX file as stars.tex:
%&latex \documentclass[10pt]{article} \usepackage{graphicx} \pagestyle{empty} \begin{document} \includegraphics{stars.1} \end{document}
Then I ran
mpost stars tex stars dvips -mode ljfzzz -D 1200 stars -o convert -density 1200 -chop 99999x99999+6249+3463 -chop 2479x2095 stars.ps stars.png pngcrush -reduce -brute -l 9 stars.png stars.crush.png
stars.crush.png was the final output file.
(Apparently it's non-trivial to get dvips to use a given resolution. I would have preferred to use 1600 dpi, but dvips didn't already have a "printer" at that resolution. ljfzzz, at 1200, was the best I could find.)
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License.http://www.gnu.org/copyleft/fdl.htmlGFDLGNU Free Documentation Licensetruetrue |
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. | ||
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This licensing tag was added to this file as part of the GFDL licensing update.http://creativecommons.org/licenses/by-sa/3.0/CC BY-SA 3.0Creative Commons Attribution-Share Alike 3.0truetrue |
- You are free:
- to share – to copy, distribute and transmit the work
- to remix – to adapt the work
- Under the following conditions:
- attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
- share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.
References
- I took the star colors from [1], which indicates they're only approximate. Apparently there are inherent difficulties in representing a star's color on a computer monitor.
- I took the star radii from [2].
derivative works
Derivative works of this file:
- Alpha Centauri relative sizes-it.png
- Alpha Centauri relative sizes-nl.png
- Alpha Centauri relative sizes-sv.png
Items portrayed in this file
depicts
image/png
29cb58d75fe8fe45f339a7a486163d387f9b7909
57,447 byte
1,368 pixel
3,770 pixel
File history
Click on a date/time to view the file as it appeared at that time.
Date/Time | Thumbnail | Dimensions | User | Comment | |
---|---|---|---|---|---|
current | 05:41, 4 February 2005 | 3,770 × 1,368 (56 KB) | Dbenbenn | sans serif fonts version | |
06:42, 30 January 2005 | 5,029 × 1,825 (94 KB) | Dbenbenn | higher resolution version | ||
03:50, 30 January 2005 | 2,515 × 913 (24 KB) | Dbenbenn | star size and color comparison |
File usage
The following 4 pages use this file: