From: Szymon 'tichy' <ssbm2@...2.pl>
Date: 2007-09-20T00:25:03+09:00
Subject: Re: How to compute Sunrise / Sunset ?

I overlooked straight solution...
Emacs editor has a calendar.
I think code in solar.el file is accurate.

http://cvs.savannah.gnu.org/viewvc/emacs/emacs/lisp/calendar/solar.el?view=markup