Date.fromJulian= function(j){
    j= (+j)+(30.0/(24*60*60));
    var A= Date.julianArray(j, true);
    return new Date(Date.UTC.apply(Date, A));
}
Date.julianArray= function(j, n){
    var F= Math.floor;
    var j2, JA, a, b, c, d, e, f, g, h, z;
    j+= .5;
    j2= (j-F(j))*86400.0;
    z= F(j);
    f= j-z;
    if(z< 2299161) a= z;
    else{
        g= F((z-1867216.25)/36524.25);
        a= z+1+g-F(g/4);
    }
    b= a+1524;
    c= F((b-122.1)/365.25);
    d= F(365.25*c);
    e= F((b-d)/30.6001);
    h= F((e< 14)? (e-1): (e-13));
    var JA= [F((h> 2)? (c-4716): (c-4715)),
    h-1, F(b-d-F(30.6001*e)+f)];
    var JB= [F(j2/3600), F((j2/60)%60), Math.round(j2%60)];
    JA= JA.concat(JB);
    if(typeof n== 'number') return JA.slice(0, n);
    return JA;
}
Date.getSeasons= function(y, wch){
    y= y || new Date().getFullYear();
    if(y<1000 || y> 3000) throw y+' is out of range';
    var Y1= (y-2000)/1000, Y2= Y1*Y1, Y3= Y2*Y1, Y4= Y3*Y1;
    var jd, t, w, d, est= 0, i= 0, Cos= Math.degCos, A= [y],
    e1= [485, 203, 199, 182, 156, 136, 77, 74, 70, 58, 52, 50, 45, 44, 29, 18, 17, 16, 14, 12, 12, 12, 9, 8],
    e2= [324.96, 337.23, 342.08, 27.85, 73.14, 171.52, 222.54, 296.72, 243.58, 119.81, 297.17, 21.02,
    247.54, 325.15, 60.93, 155.12, 288.79, 198.04, 199.76, 95.39, 287.11, 320.81, 227.73, 15.45],
    e3= [1934.136, 32964.467, 20.186, 445267.112, 45036.886, 22518.443,
    65928.934, 3034.906, 9037.513, 33718.147, 150.678, 2281.226,
    29929.562, 31555.956, 4443.417, 67555.328, 4562.452, 62894.029,
    31436.921, 14577.848, 31931.756, 34777.259, 1222.114, 16859.074];
    while(i< 4){
        switch(i){
            case 0: jd= 2451623.80984 + 365242.37404*Y1 + 0.05169*Y2 - 0.00411*Y3 - 0.00057*Y4;
            break;
            case 1: jd= 2451716.56767 + 365241.62603*Y1 + 0.00325*Y2+ 0.00888*Y3 - 0.00030*Y4;
            break;
            case 2: jd= 2451810.21715 + 365242.01767*Y1 - 0.11575*Y2 + 0.00337*Y3 + 0.00078*Y4;
            break;
            case 3: jd= 2451900.05952 + 365242.74049*Y1 - 0.06223*Y2 - 0.00823*Y3 + 0.00032*Y4;
            break;
        }
        var t= (jd- 2451545.0)/36525,
        w= 35999.373*t - 2.47,
        d= 1 + 0.0334*Cos(w)+ 0.0007*Cos(2*w);
        est= 0;
        for(var n= 0; n<24; n++){
            est += e1[n]*Cos(e2[n]+(e3[n]*t));
        }
        jd+= (0.00001*est)/d;
        A[++i]= Date.fromJulian(jd);
    }
    return wch && A[wch]? A[wch]: A;
}
Math.degRad= function(d){
    return (d*Math.PI)/180.0
}
Math.degSin= function(d){
    return Math.sin(Math.degRad(d))
}
Math.degCos= function(d){
    return Math.cos(Math.degRad(d))
}