public static JulianDay FindPhase(int year, int month, int day, MoonPhases phase)
{
var jd = new JulianDay(year, month, day);
double length = 365;
if (jd.IsLeapYear)
{
length = 366;
}
double Y = Math.Round(year + ((double)jd.DayOfYear / length), 2);
double k = ((Y - 2000) * 12.3685);
switch (phase)
{
case MoonPhases.New:
k = Math.Round(k);
break;
case MoonPhases.FirstQuarter:
if (k < 0)
{
k = Math.Round(k) - 0.25;
}
else
{
k = Math.Floor(k) + 0.25;
}
break;
case MoonPhases.Full:
if (k < 0)
{
k = Math.Round(k) - 0.50;
}
else
{
k = Math.Floor(k) + 0.50;
}
break;
case MoonPhases.LastQuarter:
if (k < 0)
{
k = Math.Round(k) - 0.75;
}
else
{
k = Math.Floor(k) + 0.75;
}
break;
}
Debug.WriteLine("k\t=\t" + Math.Round(k, 2));
double T = k / 1236.85;
double T2 = Math.Pow(T, 2);
double T3 = Math.Pow(T, 3);
double T4 = Math.Pow(T, 4);
Debug.WriteLine("T\t=\t" + Math.Round(T, 5));
double JDE = 2451550.09766 + 29.530588861 * k
+ 0.00015437 * T2
- 0.000000150 * T3
+ 0.00000000073 * T4;
Debug.WriteLine("JDE\t=\t" + Math.Round(JDE, 5));
//Corrections
double E = 1 - 0.002516 * T - 0.0000074 * T2;
double M = 2.5534 + 29.10535670 * k
- 0.0000014 * T2
- 0.00000011 * T3;
Debug.Write("M\t=\t" + Math.Round(M, 4));
M = AstroMath.Mod(M, 360);
Debug.WriteLine("\t=\t" + Math.Round(M, 4));
double Mp = 201.5643 + (385.81693528 * k)
+ (0.0107582 * T2)
+ (0.00001238 * T3)
- (0.000000058 * T4);
Debug.Write("M′\t=\t" + Math.Round(Mp, 4));
Mp = AstroMath.Mod(Mp, 360);
Debug.WriteLine("\t=\t" + Math.Round(Mp, 4));
double F = 160.7180 + 390.67050284 * k
- 0.0016118 * T2
- 0.00000227 * T3
+ 0.000000011 * T4;
Debug.Write("F\t=\t" + Math.Round(F, 4));
F = AstroMath.Mod(F, 360);
Debug.WriteLine("\t=\t" + Math.Round(F, 4));
double Ω = 124.7746 - (1.56375588 * k)
+ (0.0020672 * T2)
+ (0.00000215 * T3);
Debug.Write("Ω\t=\t" + Math.Round(Ω, 4));
Ω = AstroMath.Mod(Ω, 360);
Debug.WriteLine("\t=\t" + Math.Round(Ω, 4));
double correction = 0;
//switch (phase)
//{
// case MoonPhases.Full:
// correction = FullMoonCorrections(E, M, Mp, F, Ω);
// break;
//}
//PlanetaryArguments
double additionalCorrection = 0;
for (int i = 0; i <= 13; i++)
{
IList <double> S = PlanetaryArguments[i];
additionalCorrection += AdditionalCorrections[i] * AstroMath.Sin(S[0] + (S[1] * k) - (S[2] * T2));
}
Debug.WriteLine("Additional Corrections:\t" + Math.Round(additionalCorrection, 5));
JDE = JDE + correction + additionalCorrection;
return(new JulianDay(JDE));
}
private static double Correction(double Term1, double Term2)
{
return(Term1 * AstroMath.Sin(Term2));
}