// JavaScript by Peter Hayes http://www.peter-hayes.freeserve.co.uk/ // Copyright 2001-2003 // This code is made freely available but please keep this notice. // I accept no liability for any errors in my coding but please // let me know of any errors you find. My address is on my home page. // Various functions for the Sun // Nutation in longitude and obliquity, returns seconds function nutation(obs) { var T=(jd(obs)-2451545.0)/36525.0; var T2=T*T; var T3=T2*T; var omega=rev(125.04452-1934.136261*T); var L=rev(280.4665+36000.7698*T); var LP=rev(218.3165+481267.8813*T); var deltaL=-17.20*sind(omega)-1.32*sind(2*L)-0.23*sind(2*LP)+0.21*sind(2*omega); var deltaO=9.20*cosd(omega)+0.57*cosd(2*L)+0.10*cosd(2*LP)-0.09*cosd(2*omega); return new Array(deltaL,deltaO); } // Obliquity of ecliptic function obl_eql(obs) { var T=(jd(obs)-2451545.0)/36525; var T2=T*T; var T3=T2*T; var e0=23.0+(26.0/60.0)+(21.448-46.8150*T-0.00059*T2+0.001813*T3)/3600.0; var nut=nutation(obs); var e=e0+nut[1]/3600.0; return e; } // Eccentricity of Earths Orbit function earth_ecc(obs) { var T=(jd(obs)-2451545.0)/36525; var T2=T*T; var T3=T2*T; var e=0.016708617-0.000042037*T-0.0000001236*T2; return e; } // The equation of time function returns minutes function EoT(obs) { var sun_xyz=new Array(0.0,0.0,0.0); var earth_xyz=helios(planets[2],obs); var radec=radecr(sun_xyz,earth_xyz,obs); var T=(jd(obs)-2451545.0)/365250; var T2=T*T; var T3=T2*T; var T4=T3*T; var T5=T4*T; var L0=rev(280.4664567+360007.6982779*T+0.03032028*T2+ T3/49931.0-T4/15299.0-T5/1988000.0); var nut=nutation(obs); var delta=nut[0]/3600.0; var e=obl_eql(obs); var E=4*(L0-0.0057183-(radec[0]*15.0)+delta*cosd(e)); while (E < -1440) E+=1440; while (E > 1440) E-=1440; return E; } // Sun rise/set // obs is the observer // twilight is one of the following // for actual rise and set -0.833 // for civil rise and set -6.0 // for nautical rise and set -12.0 // for astronomical rise and set -18.0 function sunrise(obs,twilight) { // obs is a reference variable make a copy var obscopy=new Object(); for (var i in obs) obscopy[i] = obs[i]; var riseset=new Array("",""); obscopy.hours=12; obscopy.minutes=0; obscopy.seconds=0; lst=local_sidereal(obscopy); earth_xyz=helios(planets[2],obscopy); sun_xyz=new Array(0.0,0.0,0.0); radec=radecr(sun_xyz,earth_xyz,obscopy); var UTsun=12.0+radec[0]-lst; if (UTsun < 0.0) UTsun+=24.0; if (UTsun > 24.0) UTsun-=24.0; cosLHA=(sind(twilight)-sind(obs.latitude)*sind(radec[1])) / (cosd(obs.latitude)*cosd(radec[1])); // Check for midnight sun and midday night. if (cosLHA > 1.0) { riseset[0]="----"; riseset[1]="----"; } else if (cosLHA < -1.0) { riseset[0]="++++"; riseset[1]="++++"; } else { // rise/set times allowing for not today. lha=acosd(cosLHA)/15.0; if ((UTsun-lha) < 0.0) { riseset[0]=hmstring(24.0+UTsun-lha); } else { riseset[0]=hmstring(UTsun-lha); } if ((UTsun+lha) > 24.0) { riseset[1]=hmstring(UTsun+lha-24.0); } else { riseset[1]=hmstring(UTsun+lha); } } return(riseset); } function doSun(obs,repeat) { // doSun creates the Sun window // obs is the observer // repeat = 0 only do for 1 day // repeat = 1 do for several days // repeat = 3 do for the full month var oname=sitename(); var i; var obscopy=new Object(); for (var i in obs) obscopy[i] = obs[i]; var sun_xyz=new Array(0.0,0.0,0.0); // var pwin=window.open("","sun","left="+window.screenX+",top="+window.screenY+ // ",menubar,scrollbars,resizable"); var pwin=window.open("","sun","menubar,scrollbars,resizable"); with (pwin.document) { writeln(""); writeln(""); writeln("Efemérides - Sol"); writeln(""); writeln(""); writeln(""); write("

Efemérides del Sol para "+oname); if (repeat==0) { writeln("
Fecha = "+datestring(obscopy)); writeln(" Hora = "+timestring(obscopy,false)+"

"); } else { writeln("
Hora = "+timestring(obscopy,false)+""); } writeln(""); if (repeat>=1) { writeln(""); } writeln(""); writeln(""); writeln(""); writeln(""); writeln(""); writeln(""); writeln(""); writeln(""); writeln(""); var count=1; if (repeat>=1) { var lastdst=checkdst(obscopy); if (repeat==2) { var count=month_length[obscopy.month-1]; obscopy.day=1; } else { var count=document.table1.Times.selectedIndex+1; } } while (count>0) { writeln(""); if (repeat>=1) writeln(""); var earth_xyz=helios(planets[2],obscopy); var radec=radecr(sun_xyz,earth_xyz,obscopy); var altaz=radtoaa(radec[0],radec[1],obscopy); writeln(""); writeln(""); writeln(""); writeln(""); writeln(""); // Do the various twilight definitions var twilight= new Array(-0.833,-6.0,-12.0,-18.0); var i; for (var i=0; i<4; i++) { riseset=sunrise(obscopy,twilight[i]); writeln(""); writeln(""); } writeln(""); if (repeat==0) break; count-=1; if (repeat==1) { obscopy.day+=document.table1.Step.selectedIndex+1; } else { obscopy.day+=1; } if (obscopy.day > month_length[obscopy.month-1]) { obscopy.day-=month_length[obscopy.month-1]; obscopy.month+=1; if (obscopy.month==13) { obscopy.year+=1; obscopy.month=1; } } // check if the repeats cross daylight saving boundary var dst=checkdst(obscopy); if (lastdst != dst) { writeln(""); obscopy.tz+=(dst-lastdst); lastdst=dst; } } writeln("
FechaAscensión RectaDeclinaciónAltitudAzimutDistancia a la TierraSalida/OcasoC.Civil Inicio/FinC.Náutico Inicio/FinC.Astronómico Inicio/Fin
"+datestring(obscopy)+""+hmstring(radec[0])+""+anglestring(radec[1],false)+""+anglestring(altaz[0],false)+""+anglestring(altaz[1],true)+""+Math.round(radec[2]*1000.0)/1000.0+""+riseset[0]+""+riseset[1]+"
Clocks Changed

"); writeln(""); write(""); write(""); writeln("
ImprimirCerrar

"); close(); } pwin.focus(); }