Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/5/84; site gloria.UUCP Path: utzoo!watmath!clyde!cbosgd!cbdkc1!desoto!packard!edsel!bentley!hoxna!houxm!mhuxr!ulysses!allegra!bellcore!decvax!genrad!teddy!panda!talcott!harvard!seismo!rochester!rocksanne!sunybcs!gloria!colonel From: colonel@gloria.UUCP Newsgroups: net.astro,net.physics Subject: Re: sunrise and sunset Message-ID: <739@gloria.UUCP> Date: Sun, 23-Dec-84 14:24:21 EST Article-I.D.: gloria.739 Posted: Sun Dec 23 14:24:21 1984 Date-Received: Thu, 27-Dec-84 03:26:23 EST References: <1043@aecom.UUCP> Organization: SUNY-Buffalo Confuser Science Lines: 28 > Does anyone out there know an equation for sunrise and sunset > given the day of the year? This isn't quite what you want, but you're welcome to it. It gives the DIRECTION of sunset at the solstice at various latitudes. (One look will tell you why I wrote it in FORTRAN.) 23.5 is the earth's tilt, more or less. t=sind(23.5) print 1, (i, asind(t/cosd(float(i))),i=0,66) 1 format (1x,i2,3x,f8.1) stop end function sind(x) sind=sin(x*3.14159/180) return end function cosd(x) cosd=cos(x*3.14159/180) return end function asind(x) asind=180/3.14159*asin(x) return end -- Col. G. L. Sicherman ...seismo!rochester!rocksanne!rocksvax!sunybcs!gloria!colonel