Image:Alpha Centauri relative sizes.png
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A comparison of the sizes and colors of the stars in the Alpha Centauri system with the Sun.
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.)
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