Like with what we did the Moon phase, the method of calculating the Moon age is the same, for the most part, as finding the Moon’s position.

The only difference is in finding the formula for finding the distance
Distance = (Semi-major axis) * (1 – (ecc * ecc)) / (1 + (ecc * Cos(MM1 + MEC)))
where MM1 and MEC come from the calculation

		public static void CalcMoonDistance(DateTime dDate, DateTime dEpoch, double fMEpochLong, double fMPeriLong, double fMAscNode, double fMIncl, double fMEcc, double fSEpochEclLong, double fSPeriEclLong, double fSEcc, double fMSMA, ref double fMDistance)
		{
			double fN, fSM, fSE, fSLambda;
			double fL, fMM, fMN, fME, fAE, fMEC, fA3, fMM1;
			double fJD1, fJD2, fDays;

			fJD1 = UraniaTime.GetJulianDay(dDate, 0);
			fJD2 = UraniaTime.GetJulianDay(dEpoch, 0);
			fDays = (fJD1 - fJD2);
			fDays += 1;

			fN = (360.0/365.242191) * fDays;
			fN = Trig.PutIn360Deg(fN);
			fSM = fN + fSEpochEclLong - fSPeriEclLong;
			fSM = Trig.PutIn360Deg(fSM);

			fSE = (360.0 / Math.PI) * fSEcc * Math.Sin(Trig.DegToRad(fSM));
			fSLambda = fN + fSE + fSEpochEclLong;

			fL = (13.176396 * fDays) + fMEpochLong;
			fL = Trig.PutIn360Deg(fL);
			
			fMM = fL - (0.111404 * fDays) - fMPeriLong;
			fMM = Trig.PutIn360Deg(fMM);

			fMN = fMAscNode - (0.0529539 * fDays);
			fMN = Trig.PutIn360Deg(fMN);

			fME = 1.2739 * Trig.Sin((2.0 * (fL - fSLambda)) - fMM);
			fAE = 0.1858 * Trig.Sin(fSM);
			fA3 = 0.37 * Trig.Sin(fSM);

			fMM1 = fMM + fME - fAE + fA3;
			
			fMEC = 6.2886 * Trig.Sin(fMM1);

			fMDistance = fMSMA * ((1.0 - (fMEcc * fMEcc))/(1.0 + (fMEcc * Trig.Cos(fMM1 + fMEC))));
		}
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