using System; using System.Collections.Generic; namespace CoordinateSharp { internal class MoonCalc { static readonly Double rad = Math.PI / 180; //For converting radians //obliquity of the ecliptic in radians based on standard equinox 2000. static readonly Double e = rad * 23.4392911; /// /// Gets Moon Times, Altitude and Azimuth /// /// Date /// Latitude /// Longitude /// Celestial public static void GetMoonTimes(DateTime date, Double lat, Double lng, Celestial c) { //Get current Moon Position to populate passed Alt / Azi for user specified date MoonPosition mp = GetMoonPosition(date, lat, lng, c); Double altRad = mp.Altitude / Math.PI * 180; //Convert alt to degrees c.moonAltitude = altRad - mp.ParallaxCorection; //Set altitude with adjusted parallax c.moonAzimuth = mp.Azimuth / Math.PI * 180 + 180; //Azimuth in degrees + 180 for E by N. ////New Iterations for Moon set / rise Boolean moonRise = false; Boolean moonSet = false; //Start at beginning of day DateTime t = new DateTime(date.Year, date.Month, date.Day, 0, 0, 0, DateTimeKind.Utc); //Get start of day Moon Pos MoonPosition moonPos = GetMoonPosition(t, lat, lng, c); Double alt1 = moonPos.Altitude - moonPos.ParallaxCorection * rad; DateTime? setTime = null; DateTime? riseTime = null; Double hz = -.3 * rad;//Horizon degrees at -.3 for appearant rise / set //Iterate for each hour of the day for (Int32 x = 1; x <= 24; x++) { moonPos = GetMoonPosition(t.AddHours(x), lat, lng, c);//Get the next hours altitude for comparison Double alt2 = moonPos.Altitude - moonPos.ParallaxCorection * rad; //If hour 1 is below horizon and hour 2 is above if (alt1 < hz && alt2 >= hz) { //Moon Rise Occurred moonRise = true; DateTime dt1 = t.AddHours(x - 1); moonPos = GetMoonPosition(dt1, lat, lng, c);//Get the next hours altitude for comparison Double altM1 = moonPos.Altitude - moonPos.ParallaxCorection * rad; //Iterate through each minute to determine at which minute the horizon is crossed. //Interpolation is more efficient, but yielded results with deviations up to 5 minutes. //Investigate formula efficiency for (Int32 y = 1; y <= 60; y++) { DateTime dt2 = t.AddHours(x - 1).AddMinutes(y); moonPos = GetMoonPosition(dt2, lat, lng, c);//Get the next hours altitude for comparison Double altM2 = moonPos.Altitude - moonPos.ParallaxCorection * rad; if (altM1 < hz && altM2 >= hz) { //interpolate seconds Double p = 60 * ((hz - altM1) / (altM2 - altM1)); riseTime = dt1.AddMinutes(y - 1).AddSeconds(p); break; } altM1 = altM2; } } //if hour 2 is above horizon and hour 1 below if (alt1 >= hz && alt2 < hz) { //Moon Set Occured moonSet = true; DateTime dt1 = t.AddHours(x - 1); moonPos = GetMoonPosition(dt1, lat, lng, c);//Get the next hours altitude for comparison Double altM1 = moonPos.Altitude - moonPos.ParallaxCorection * rad; //Iterate through each minute to determine at which minute the horizon is crossed. //Interpolation is more efficient, but yielded results with deviations up to 5 minutes. //Investigate formula efficiency for (Int32 y = 1; y <= 60; y++) { DateTime dt2 = t.AddHours(x - 1).AddMinutes(y); moonPos = GetMoonPosition(dt2, lat, lng, c);//Get the next hours altitude for comparison Double altM2 = moonPos.Altitude - moonPos.ParallaxCorection * rad; if (altM1 >= hz && altM2 < hz) { //Interpolate seconds Double p = 60 * ((hz - altM2) / (altM1 - altM2)); setTime = dt1.AddMinutes(y).AddSeconds(-p); break; } altM1 = altM2; } } alt1 = alt2; if (moonRise && moonSet) { break; } } c.moonSet = setTime; c.moonRise = riseTime; if (moonRise && moonSet) { c.moonCondition = CelestialStatus.RiseAndSet; } else { if (!moonRise && !moonSet) { c.moonCondition = alt1 >= 0 ? CelestialStatus.UpAllDay : CelestialStatus.DownAllDay; } if (!moonRise && moonSet) { c.moonCondition = CelestialStatus.NoRise; } if (moonRise && !moonSet) { c.moonCondition = CelestialStatus.NoSet; } } } private static MoonPosition GetMoonPosition(DateTime date, Double lat, Double lng, Celestial cel) { //Set UTC date integrity date = new DateTime(date.Year, date.Month, date.Day, date.Hour, date.Minute, date.Second, DateTimeKind.Utc); Double d = JulianConversions.GetJulian_Epoch2000(date); //Ch 47 Double JDE = JulianConversions.GetJulian(date);//Get julian Double T = (JDE - 2451545) / 36525; //Get dynamic time. Double[] LDMNF = Get_Moon_LDMNF(T); CelCoords c = GetMoonCoords(d, cel, LDMNF, T); Distance dist = GetMoonDistance(date); Double lw = rad * -lng; Double phi = rad * lat; Double H = rad * MeeusFormulas.Get_Sidereal_Time(JDE) - lw - c.Ra; Double ra = c.Ra; //Adjust current RA formula to avoid needless RAD conversions Double dec = c.Dec; //Adjust current RA formula to avoid needless RAD conversions //Adjust for parallax (low accuracry increases may not be worth cost) //Investigate Double pSinE = Get_pSinE(dec, dist.Meters) * Math.PI / 180; Double pCosE = Get_pCosE(dec, dist.Meters) * Math.PI / 180; Double cRA = Parallax_RA(dist.Meters, H, pCosE, dec, ra); Double tDEC = Parallax_Dec(dist.Meters, H, pCosE, pSinE, dec, cRA); //Double tRA = ra - cRA; dec = tDEC; //ra = tRA; //Get true altitude Double h = Altitude(H, phi, dec); // formula 14.1 of "Astronomical Algorithms" 2nd edition by Jean Meeus (Willmann-Bell, Richmond) 1998. Double pa = Math.Atan2(Math.Sin(H), Math.Tan(phi) * Math.Cos(dec) - Math.Sin(dec) * Math.Cos(H)); //altitude correction for refraction h += AstroRefraction(h); MoonPosition mp = new MoonPosition { Azimuth = Azimuth(H, phi, dec), Altitude = h / Math.PI * 180, Distance = dist, ParallacticAngle = pa }; Double horParal = 8.794 / (dist.Meters / 149.59787E6); // horizontal parallax (arcseconds), Meeus S. 263 Double p = Math.Asin(Math.Cos(h) * Math.Sin(horParal / 3600)); // parallax in altitude (degrees) p *= 1000; mp.ParallaxCorection = p; mp.Altitude *= rad; return mp; } private static CelCoords GetMoonCoords(Double _1, Celestial _2, Double[] LDMNF, Double t) { // Legacy function. Updated with Meeus Calcs for increased accuracy. // geocentric ecliptic coordinates of the moon // Meeus Ch 47 Double[] cs = Get_Moon_Coordinates(LDMNF, t); Double l = cs[0]; // longitude Double b = cs[1]; // latitude CelCoords mc = new CelCoords { Ra = RightAscension(l, b), Dec = Declination(l, b) }; //Double ra = mc.ra / Math.PI * 180; //Double dec = mc.dec / Math.PI * 180; return mc; } public static void GetMoonIllumination(DateTime date, Celestial c, Double lat, Double lng) { date = new DateTime(date.Year, date.Month, date.Day, date.Hour, date.Minute, date.Second, DateTimeKind.Utc); Double d = JulianConversions.GetJulian_Epoch2000(date); CelCoords s = GetSunCoords(d); Double JDE = JulianConversions.GetJulian(date);//Get julian Double T = (JDE - 2451545) / 36525; //Get dynamic time. Double[] LDMNF = Get_Moon_LDMNF(T); CelCoords m = GetMoonCoords(d, c, LDMNF, T); Double sdist = 149598000, phi = Math.Acos(Math.Sin(s.Dec) * Math.Sin(m.Dec) + Math.Cos(s.Dec) * Math.Cos(m.Dec) * Math.Cos(s.Ra - m.Ra)), inc = Math.Atan2(sdist * Math.Sin(phi), m.Dist - sdist * Math.Cos(phi)), angle = Math.Atan2(Math.Cos(s.Dec) * Math.Sin(s.Ra - m.Ra), Math.Sin(s.Dec) * Math.Cos(m.Dec) - Math.Cos(s.Dec) * Math.Sin(m.Dec) * Math.Cos(s.Ra - m.Ra)); MoonIllum mi = new MoonIllum { Fraction = (1 + Math.Cos(inc)) / 2, Phase = 0.5 + 0.5 * inc * (angle < 0 ? -1 : 1) / Math.PI, Angle = angle }; c.moonIllum = mi; String moonName = ""; Int32 moonDate = 0; //GET PHASE NAME //CHECK MOON AT BEGINNING AT END OF DAY TO GET DAY PHASE DateTime dMon = new DateTime(date.Year, date.Month, 1); for (Int32 x = 1; x <= date.Day; x++) { DateTime nDate = new DateTime(dMon.Year, dMon.Month, x, 0, 0, 0, DateTimeKind.Utc); d = JulianConversions.GetJulian_Epoch2000(nDate); s = GetSunCoords(d); JDE = JulianConversions.GetJulian(nDate);//Get julian T = (JDE - 2451545) / 36525; //Get dynamic time. LDMNF = Get_Moon_LDMNF(T); m = GetMoonCoords(d, c, LDMNF, T); phi = Math.Acos(Math.Sin(s.Dec) * Math.Sin(m.Dec) + Math.Cos(s.Dec) * Math.Cos(m.Dec) * Math.Cos(s.Ra - m.Ra)); inc = Math.Atan2(sdist * Math.Sin(phi), m.Dist - sdist * Math.Cos(phi)); angle = Math.Atan2(Math.Cos(s.Dec) * Math.Sin(s.Ra - m.Ra), Math.Sin(s.Dec) * Math.Cos(m.Dec) - Math.Cos(s.Dec) * Math.Sin(m.Dec) * Math.Cos(s.Ra - m.Ra)); Double startPhase = 0.5 + 0.5 * inc * (angle < 0 ? -1 : 1) / Math.PI; nDate = new DateTime(dMon.Year, dMon.Month, x, 23, 59, 59, DateTimeKind.Utc); d = JulianConversions.GetJulian_Epoch2000(nDate); s = GetSunCoords(d); JDE = JulianConversions.GetJulian(nDate);//Get julian T = (JDE - 2451545) / 36525; //Get dynamic time. LDMNF = Get_Moon_LDMNF(T); m = GetMoonCoords(d, c, LDMNF, T); phi = Math.Acos(Math.Sin(s.Dec) * Math.Sin(m.Dec) + Math.Cos(s.Dec) * Math.Cos(m.Dec) * Math.Cos(s.Ra - m.Ra)); inc = Math.Atan2(sdist * Math.Sin(phi), m.Dist - sdist * Math.Cos(phi)); angle = Math.Atan2(Math.Cos(s.Dec) * Math.Sin(s.Ra - m.Ra), Math.Sin(s.Dec) * Math.Cos(m.Dec) - Math.Cos(s.Dec) * Math.Sin(m.Dec) * Math.Cos(s.Ra - m.Ra)); Double endPhase = 0.5 + 0.5 * inc * (angle < 0 ? -1 : 1) / Math.PI; //Determine Moon Name. if (startPhase <= .5 && endPhase >= .5) { moonDate = x; moonName = GetMoonName(dMon.Month, moonName); } //Get Moon Name (month, string); //Get Moon Phase Name if (date.Day == x) { if (startPhase > endPhase) { mi.PhaseName = "New Moon"; break; } if (startPhase <= .25 && endPhase >= .25) { mi.PhaseName = "First Quarter"; break; } if (startPhase <= .5 && endPhase >= .5) { mi.PhaseName = "Full Moon"; break; } if (startPhase <= .75 && endPhase >= .75) { mi.PhaseName = "Last Quarter"; break; } if (startPhase > 0 && startPhase < .25 && endPhase > 0 && endPhase < .25) { mi.PhaseName = "Waxing Crescent"; break; } if (startPhase > .25 && startPhase < .5 && endPhase > .25 && endPhase < .5) { mi.PhaseName = "Waxing Gibbous"; break; } if (startPhase > .5 && startPhase < .75 && endPhase > .5 && endPhase < .75) { mi.PhaseName = "Waning Gibbous"; break; } if (startPhase > .75 && startPhase < 1 && endPhase > .75 && endPhase < 1) { mi.PhaseName = "Waning Crescent"; break; } } } c.AstrologicalSigns.MoonName = date.Day == moonDate ? moonName : ""; CalculateLunarEclipse(date, lat, lng, c); } public static void CalculateLunarEclipse(DateTime date, Double lat, Double longi, Celestial c) { //Convert to Radian Double latR = lat * Math.PI / 180; Double longR = longi * Math.PI / 180; List> se = LunarEclipseCalc.CalculateLunarEclipse(date, latR, longR); //RETURN FIRST AND LAST if (se.Count == 0) { return; } //FIND LAST AND NEXT ECLIPSE Int32 lastE = -1; Int32 nextE = -1; Int32 currentE = 0; DateTime lastDate = new DateTime(); DateTime nextDate = new DateTime(3300, 1, 1); //Iterate to get last and next eclipse foreach (List values in se) { DateTime ld = DateTime.ParseExact(values[0], "yyyy-MMM-dd", System.Globalization.CultureInfo.InvariantCulture); if (ld < date && ld > lastDate) { lastDate = ld; lastE = currentE; } if (ld >= date && ld < nextDate) { nextDate = ld; nextE = currentE; } currentE++; } //SET ECLIPSE DATA if (lastE >= 0) { c.LunarEclipse.LastEclipse = new LunarEclipseDetails(se[lastE]); } if (nextE >= 0) { c.LunarEclipse.NextEclipse = new LunarEclipseDetails(se[nextE]); } } private static String GetMoonName(Int32 month, String name) => name != "" ? "Blue Moon" : (month switch { 1 => "Wolf Moon", 2 => "Snow Moon", 3 => "Worm Moon", 4 => "Pink Moon", 5 => "Flower Moon", 6 => "Strawberry Moon", 7 => "Buck Moon", 8 => "Sturgeon Moon", 9 => "Corn Moon", 10 => "Hunters Moon", 11 => "Beaver Moon", 12 => "Cold Moon", _ => "", }); public static void GetMoonDistance(DateTime date, Celestial c) { date = new DateTime(date.Year, date.Month, date.Day, date.Hour, date.Minute, date.Second, DateTimeKind.Utc); c.moonDistance = GetMoonDistance(date); //Updating distance formula } //Moon Time Functions private static CelCoords GetSunCoords(Double d) { Double M = SolarMeanAnomaly(d), L = EclipticLongitude(M); CelCoords c = new CelCoords { Dec = Declination(L, 0), Ra = RightAscension(L, 0) }; return c; } private static Double SolarMeanAnomaly(Double d) => rad * (357.5291 + 0.98560028 * d); private static Double EclipticLongitude(Double M) { Double C = rad * (1.9148 * Math.Sin(M) + 0.02 * Math.Sin(2 * M) + 0.0003 * Math.Sin(3 * M)), // equation of center P = rad * 102.9372; // perihelion of the Earth return M + C + P + Math.PI; } public static void GetMoonSign(DateTime date, Celestial c) { //Formulas taken from https://www.astrocal.co.uk/moon-sign-calculator/ Double d = date.Day; Double m = date.Month; Double y = date.Year; Double hr = date.Hour; Double mi = date.Minute; Double f = hr + mi / 60; Double im = 12 * (y + 4800) + m - 3; Double j = (2 * (im - Math.Floor(im / 12) * 12) + 7 + 365 * im) / 12; j = Math.Floor(j) + d + Math.Floor(im / 48) - 32083; Double jd = j + Math.Floor(im / 4800) - Math.Floor(im / 1200) + 38; Double T = (jd - 2415020 + f / 24 - .5) / 36525; //Double ob = FNr(23.452294 - .0130125 * T); Double ll = 973563 + 1732564379 * T - 4 * T * T; Double g = 1012395 + 6189 * T; Double n = 933060 - 6962911 * T + 7.5 * T * T; Double g1 = 1203586 + 14648523 * T - 37 * T * T; d = 1262655 + 1602961611 * T - 5 * T * T; Double M = 3600; Double l = (ll - g1) / M; Double l1 = (ll - d - g) / M; f = (ll - n) / M; d /= M; y = 2 * d; Double ml = 22639.6 * FNs(l) - 4586.4 * FNs(l - y); ml = ml + 2369.9 * FNs(y) + 769 * FNs(2 * l) - 669 * FNs(l1); ml = ml - 411.6 * FNs(2 * f) - 212 * FNs(2 * l - y); ml = ml - 206 * FNs(l + l1 - y) + 192 * FNs(l + y); ml = ml - 165 * FNs(l1 - y) + 148 * FNs(l - l1) - 125 * FNs(d); ml = ml - 110 * FNs(l + l1) - 55 * FNs(2 * f - y); ml = ml - 45 * FNs(l + 2 * f) + 40 * FNs(l - 2 * f); //Double tn = n + 5392 * FNs(2 * f - y) - 541 * FNs(l1) - 442 * FNs(y); //tn = tn + 423 * FNs(2 * f) - 291 * FNs(2 * l - 2 * f); g = FNu(FNp(ll + ml)); Double sign = Math.Floor(g / 30); //Double degree = g - sign * 30; sign += 1; c.AstrologicalSigns.MoonSign = (sign.ToString()) switch { "1" => "Aries", "2" => "Taurus", "3" => "Gemini", "4" => "Cancer", "5" => "Leo", "6" => "Virgo", "7" => "Libra", "8" => "Scorpio", "9" => "Sagitarius", "10" => "Capricorn", "11" => "Aquarius", "12" => "Pisces", _ => "Pisces", }; } private static Double FNp(Double x) { Double sgn = x < 0 ? -1 : 1; return sgn * (Math.Abs(x) / 3600 / 360 - Math.Floor(Math.Abs(x) / 3600.0 / 360.0)) * 360; } private static Double FNu(Double x) => x - Math.Floor(x / 360) * 360; //private static Double FNr(Double x) => Math.PI / 180 * x; private static Double FNs(Double x) => Math.Sin(Math.PI / 180 * x); //v1.1.3 Formulas //The following formulas are either additions //or conversions of SunCalcs formulas into Meeus /// /// Grabs Perigee or Apogee of Moon based on specified time. /// Results will return event just before, or just after specified DateTime /// /// DateTime /// Event Type /// PerigeeApogee private static PerigeeApogee MoonPerigeeOrApogee(DateTime d, MoonDistanceType md) { //Perigee & Apogee Algorithms from Jean Meeus Astronomical Algorithms Ch. 50 //50.1 //JDE = 2451534.6698 + 27.55454989 * k // -0.0006691 * Math.Pow(T,2) // -0.000.01098 * Math.Pow(T,3) // -0.0000000052 * Math.Pow(T,4) //50.2 //K approx = (yv - 1999.97)*13.2555 //yv is the year + percentage of days that have occured in the year. 1998 Oct 1 is approx 1998.75 //k ending in .0 represent perigee and .5 apogee. Anything > .5 is an error. //50.3 //T = k/1325.55 Double yt = 365; //days in year if (DateTime.IsLeapYear(d.Year)) { yt = 366; } //days in year if leap year Double f = d.DayOfYear / yt; //Get percentage of year that as passed Double yv = d.Year + f; //add percentage of year passed to year. Double k = (yv - 1999.97) * 13.2555; //find approximate k using formula 50.2 //Set k decimal based on apogee or perigee k = md == MoonDistanceType.Apogee ? Math.Floor(k) + .5 : Math.Floor(k); //Find T using formula 50.3 Double T = k / 1325.55; //Find JDE using formula 50.1 Double JDE = 2451534.6698 + 27.55454989 * k - 0.0006691 * Math.Pow(T, 2) - 0.00001098 * Math.Pow(T, 3) - 0.0000000052 * Math.Pow(T, 4); //Find Moon's mean elongation at time JDE. Double D = 171.9179 + 335.9106046 * k - 0.0100383 * Math.Pow(T, 2) - 0.00001156 * Math.Pow(T, 3) + 0.000000055 * Math.Pow(T, 4); //Find Sun's mean anomaly at time JDE Double M = 347.3477 + 27.1577721 * k - 0.0008130 * Math.Pow(T, 2) - 0.0000010 * Math.Pow(T, 3); //Find Moon's argument of latitude at Time JDE Double F = 316.6109 + 364.5287911 * k - 0.0125053 * Math.Pow(T, 2) - 0.0000148 * Math.Pow(T, 3); //Normalize DMF to a 0-360 degree number D %= 360; if (D < 0) { D += 360; } M %= 360; if (M < 0) { M += 360; } F %= 360; if (F < 0) { F += 360; } //Convert DMF to radians D = D * Math.PI / 180; M = M * Math.PI / 180; F = F * Math.PI / 180; Double termsA = md == MoonDistanceType.Apogee ? MeeusTables.ApogeeTermsA(D, M, F, T) : MeeusTables.PerigeeTermsA(D, M, F, T); //Find Terms A from Table 50.A JDE += termsA; Double termsB = md == MoonDistanceType.Apogee ? MeeusTables.ApogeeTermsB(D, M, F, T) : MeeusTables.PerigeeTermsB(D, M, F, T); //Convert julian back to date DateTime date = JulianConversions.GetDate_FromJulian(JDE).Value; //Obtain distance Distance dist = GetMoonDistance(date); PerigeeApogee ap = new PerigeeApogee(date, termsB, dist); return ap; } public static Perigee GetPerigeeEvents(DateTime d) { //Iterate in 15 day increments due to formula variations. //Determine closest events to date. //per1 is last date //per2 is next date //integrity for new date. if (d.Year <= 0001) { return new Perigee(new PerigeeApogee(new DateTime(), 0, new Distance(0)), new PerigeeApogee(new DateTime(), 0, new Distance(0))); } //Start at lowest increment PerigeeApogee per1 = MoonPerigeeOrApogee(d.AddDays(-45), MoonDistanceType.Perigee); PerigeeApogee per2 = MoonPerigeeOrApogee(d.AddDays(-45), MoonDistanceType.Perigee); for (Int32 x = -30; x <= 45; x += 15) { //used for comparison PerigeeApogee t = MoonPerigeeOrApogee(d.AddDays(x), MoonDistanceType.Perigee); //Find the next pergiee after specified date if (t.Date > per2.Date && t.Date >= d) { per2 = t; break; } //Find last perigee before specified date if (t.Date > per1.Date && t.Date < d) { per1 = t; per2 = t; } } return new Perigee(per1, per2); } public static Apogee GetApogeeEvents(DateTime d) { //Iterate in 5 month increments due to formula variations. //Determine closest events to date. //apo1 is last date //apo2 is next date //integrity for new date. if (d.Year <= 0001) { return new Apogee(new PerigeeApogee(new DateTime(), 0, new Distance(0)), new PerigeeApogee(new DateTime(), 0, new Distance(0))); } PerigeeApogee apo1 = MoonPerigeeOrApogee(d.AddDays(-45), MoonDistanceType.Apogee); PerigeeApogee apo2 = MoonPerigeeOrApogee(d.AddDays(-45), MoonDistanceType.Apogee); for (Int32 x = -30; x <= 45; x += 15) { PerigeeApogee t = MoonPerigeeOrApogee(d.AddDays(x), MoonDistanceType.Apogee); //Find next apogee after specified date if (t.Date > apo2.Date && t.Date >= d) { apo2 = t; break; } //Find last apogee before specified date if (t.Date > apo1.Date && t.Date < d) { apo1 = t; apo2 = t; } } return new Apogee(apo1, apo2); } /// /// Gets moon distance (Ch 47). /// /// DateTime /// Distance public static Distance GetMoonDistance(DateTime d) { //Ch 47 Double JDE = JulianConversions.GetJulian(d);//Get julian Double T = (JDE - 2451545) / 36525; //Get dynamic time. Double[] values = Get_Moon_LDMNF(T); Double D = values[1]; Double M = values[2]; Double N = values[3]; Double F = values[4]; //Ch 47 distance formula Double dist = 385000.56 + MeeusTables.Moon_Periodic_Er(D, M, N, F, T) / 1000; return new Distance(dist); } /*private static Distance GetMoonDistance(DateTime d, Double[] values) { //Ch 47 Double JDE = JulianConversions.GetJulian(d);//Get julian Double T = (JDE - 2451545) / 36525; //Get dynamic time. Double D = values[1]; Double M = values[2]; Double N = values[3]; Double F = values[4]; Double dist = 385000.56 + MeeusTables.Moon_Periodic_Er(D, M, N, F, T) / 1000; return new Distance(dist); }*/ /// /// Gets Moon L, D, M, N, F values /// Ch. 47 /// /// Dynamic Time /// double[] containing L,D,M,N,F static Double[] Get_Moon_LDMNF(Double T) { //T = dynamic time //Moon's mean longitude Double L = 218.316447 + 481267.88123421 * T - .0015786 * Math.Pow(T, 2) + Math.Pow(T, 3) / 538841 - Math.Pow(T, 4) / 65194000; //Moon's mean elongation Double D = 297.8501921 + 445267.1114034 * T - 0.0018819 * Math.Pow(T, 2) + Math.Pow(T, 3) / 545868 - Math.Pow(T, 4) / 113065000; //Sun's mean anomaly Double M = 357.5291092 + 35999.0502909 * T - .0001536 * Math.Pow(T, 2) + Math.Pow(T, 3) / 24490000; //Moon's mean anomaly Double N = 134.9633964 + 477198.8675055 * T + .0087414 * Math.Pow(T, 2) + Math.Pow(T, 3) / 69699 - Math.Pow(T, 4) / 14712000; //Moon's argument of latitude Double F = 93.2720950 + 483202.0175233 * T - .0036539 * Math.Pow(T, 2) - Math.Pow(T, 3) / 3526000 + Math.Pow(T, 4) / 863310000; //Normalize DMF to a 0-360 degree number D %= 360; if (D < 0) { D += 360; } M %= 360; if (M < 0) { M += 360; } N %= 360; if (N < 0) { N += 360; } F %= 360; if (F < 0) { F += 360; } //Convert DMF to radians D = D * Math.PI / 180; M = M * Math.PI / 180; N = N * Math.PI / 180; F = F * Math.PI / 180; return new Double[] { L, D, M, N, F }; } /// /// Get moons lat/long in radians (Ch 47). /// /// L,D,M,N,F /// Dynamic Time /// Lat[0], Long[1] private static Double[] Get_Moon_Coordinates(Double[] LDMNF, Double T) { //Refence Ch 47. Double lat = LDMNF[0] + MeeusTables.Moon_Periodic_El(LDMNF[0], LDMNF[1], LDMNF[2], LDMNF[3], LDMNF[4], T) / 1000000; Double longi = MeeusTables.Moon_Periodic_Eb(LDMNF[0], LDMNF[1], LDMNF[2], LDMNF[3], LDMNF[4], T) / 1000000; lat %= 360; if (lat < 0) { lat += 360; } //Convert to radians Double l = rad * lat; // longitude Double b = rad * longi; // latitude return new Double[] { l, b }; } /// /// Gets right Ascension of celestial object (Ch 13 Fig 13.3) /// /// latitude in radians /// longitude in radian /// Right Ascension private static Double RightAscension(Double l, Double b) => //Ch 13 Fig 13.3 //tan a = ( sin(l) * cos(e) - tan(b)-sin(e) ) / cons(l) //Converts to the following using Atan2 for 4 quadriatic regions Math.Atan2(Math.Sin(l) * Math.Cos(e) - Math.Tan(b) * Math.Sin(e), Math.Cos(l)); /// /// Gets declination of celestial object (Ch 13 Fig 13.4) /// /// latitude in radians /// longitude in radian /// Declination private static Double Declination(Double l, Double b) => //Ch 13 Fig 13.4 //sin o = sin(b) * cos(e) + cos(b)*sin(e) * sin(l) //Converts to the following using Asin Math.Asin(Math.Sin(b) * Math.Cos(e) + Math.Cos(b) * Math.Sin(e) * Math.Sin(l)); static Double Parallax_Dec(Double distance, Double H, Double pCosE, Double pSinE, Double dec, Double cRA) { //Ch 40 (Correction for parallax //H - geocentric hour angle of the body (sidereal) IAW Ch 12 Double pi = Math.Asin(Math.Sin(8.794 / distance)) * Math.PI / 180; // 40.1 in radians H = H * Math.PI / 180; //Directly to topocencric dec Double tDEC = Math.Atan2((Math.Sin(dec) - pSinE * Math.Sin(pi)) * Math.Cos(cRA), Math.Cos(dec) - pCosE * Math.Sin(pi) * Math.Cos(H)); return tDEC; } static Double Parallax_RA(Double distance, Double H, Double pCosE, Double dec, Double _) { //ENSURE RADIANS //Ch 40 (Correction for parallax //H - geocentric hour angle of the body (sidereal) IAW Ch 12 Double pi = Math.Asin(Math.Sin(8.794 / distance)) * Math.PI / 180; // 40.1 //Convert to Radian Double t = -pCosE * Math.Sin(pi) * Math.Sin(H); Double b = Math.Cos(dec) - pCosE * Math.Sin(pi) * Math.Cos(H); Double cRA = Math.Atan2(t, b); return cRA; //Topocencric RA = RA - cRA } static Double Get_pSinE(Double dec, Double H) { //ASSUME WGS 84 FOR NOW //Double a = 6378.14; //Double f = 1 / 298.257; //Double b = a * (1 - f); Double ba = .99664719; // or 1-f Double u = ba * dec * Math.PI / 180; Double ps = ba * Math.Sin(u) + H / 6378140 * Math.Sin(dec); return ps; } static Double Get_pCosE(Double dec, Double H) { //ASSUME WGS 84 FOR NOW //Double a = 6378.14; //Double f = 1 / 298.257; //Double b = a * (1 - f); Double ba = .99664719; // or 1-f Double u = ba * dec * Math.PI / 180; Double ps = Math.Cos(u) + H / 6378140 * Math.Cos(dec); return ps; } static Double Azimuth(Double H, Double phi, Double dec) => Math.Atan2(Math.Sin(H), Math.Cos(H) * Math.Sin(phi) - Math.Tan(dec) * Math.Cos(phi)); static Double Altitude(Double H, Double phi, Double dec) => Math.Asin(Math.Sin(phi) * Math.Sin(dec) + Math.Cos(phi) * Math.Cos(dec) * Math.Cos(H)); static Double AstroRefraction(Double h) { //CH 16 Double P = 1013.25; //Average pressure of earth Double T = 16; //Average temp of earth Double alt = h / Math.PI * 180; Double Ref = P * (.1594 + .0196 * alt + .00002 * Math.Pow(alt, 2)) / ((273 + T) * (1 + .505 * alt + .0845 * Math.Pow(alt, 2))); return Ref / 60; } } }