public static AASEllipticalObjectDetails Calculate(double JD, ref AASEllipticalObjectElements elements, bool bHighPrecision) { double Epsilon = AASNutation.MeanObliquityOfEcliptic(elements.JDEquinox); double JD0 = JD; //What will be the return value AASEllipticalObjectDetails details = new AASEllipticalObjectDetails(); Epsilon = AASCoordinateTransformation.DegreesToRadians(Epsilon); double omega = AASCoordinateTransformation.DegreesToRadians(elements.omega); double w = AASCoordinateTransformation.DegreesToRadians(elements.w); double i = AASCoordinateTransformation.DegreesToRadians(elements.i); double sinEpsilon = Math.Sin(Epsilon); double cosEpsilon = Math.Cos(Epsilon); double sinOmega = Math.Sin(omega); double cosOmega = Math.Cos(omega); double cosi = Math.Cos(i); double sini = Math.Sin(i); double F = cosOmega; double G = sinOmega * cosEpsilon; double H = sinOmega * sinEpsilon; double P = -sinOmega * cosi; double Q = cosOmega * cosi * cosEpsilon - sini * sinEpsilon; double R = cosOmega * cosi * sinEpsilon + sini * cosEpsilon; double a = Math.Sqrt(F * F + P * P); double b = Math.Sqrt(G * G + Q * Q); double c = Math.Sqrt(H * H + R * R); double A = Math.Atan2(F, P); double B = Math.Atan2(G, Q); double C = Math.Atan2(H, R); double n = AASElliptical.MeanMotionFromSemiMajorAxis(elements.a); AAS3DCoordinate SunCoord = AASSun.EquatorialRectangularCoordinatesAnyEquinox(JD, elements.JDEquinox, bHighPrecision); for (int j = 0; j < 2; j++) { double M = n * (JD0 - elements.T); double E = AASKepler.Calculate(M, elements.e); E = AASCoordinateTransformation.DegreesToRadians(E); double v = 2 * Math.Atan(Math.Sqrt((1 + elements.e) / (1 - elements.e)) * Math.Tan(E / 2)); double r = elements.a * (1 - elements.e * Math.Cos(E)); double x = r * a * Math.Sin(A + w + v); double y = r * b * Math.Sin(B + w + v); double z = r * c * Math.Sin(C + w + v); if (j == 0) { details.HeliocentricRectangularEquatorial = new AAS3DCoordinate { X = x, Y = y, Z = z }; //Calculate the heliocentric ecliptic coordinates also double u = w + v; double cosu = Math.Cos(u); double sinu = Math.Sin(u); details.HeliocentricRectangularEcliptical = new AAS3DCoordinate { X = r * (cosOmega * cosu - sinOmega * sinu * cosi), Y = r * (sinOmega * cosu + cosOmega * sinu * cosi), Z = r * sini * sinu }; details.HeliocentricEclipticLongitude = AASCoordinateTransformation.MapTo0To360Range(AASCoordinateTransformation.RadiansToDegrees(Math.Atan2(details.HeliocentricRectangularEcliptical.Y, details.HeliocentricRectangularEcliptical.X))); details.HeliocentricEclipticLatitude = AASCoordinateTransformation.RadiansToDegrees(Math.Asin(details.HeliocentricRectangularEcliptical.Z / r)); } double psi = SunCoord.X + x; double nu = SunCoord.Y + y; double sigma = SunCoord.Z + z; double Alpha = Math.Atan2(nu, psi); Alpha = AASCoordinateTransformation.RadiansToDegrees(Alpha); double Delta = Math.Atan2(sigma, Math.Sqrt(psi * psi + nu * nu)); Delta = AASCoordinateTransformation.RadiansToDegrees(Delta); double Distance = Math.Sqrt(psi * psi + nu * nu + sigma * sigma); if (j == 0) { details.TrueGeocentricRA = AASCoordinateTransformation.MapTo0To24Range(Alpha / 15); details.TrueGeocentricDeclination = Delta; details.TrueGeocentricDistance = Distance; details.TrueGeocentricLightTime = DistanceToLightTime(Distance); } else { details.AstrometricGeocentricRA = AASCoordinateTransformation.MapTo0To24Range(Alpha / 15); details.AstrometricGeocentricDeclination = Delta; details.AstrometricGeocentricDistance = Distance; details.AstrometricGeocentricLightTime = DistanceToLightTime(Distance); double RES = Math.Sqrt(SunCoord.X * SunCoord.X + SunCoord.Y * SunCoord.Y + SunCoord.Z * SunCoord.Z); details.Elongation = Math.Acos((RES * RES + Distance * Distance - r * r) / (2 * RES * Distance)); details.Elongation = AASCoordinateTransformation.RadiansToDegrees(details.Elongation); details.PhaseAngle = Math.Acos((r * r + Distance * Distance - RES * RES) / (2 * r * Distance)); details.PhaseAngle = AASCoordinateTransformation.RadiansToDegrees(details.PhaseAngle); } if (j == 0) { //Prepare for the next loop around JD0 = JD - details.TrueGeocentricLightTime; } } return(details); }
public static AASEllipticalObjectDetails Calculate(double JD, ref AASEllipticalObjectElements elements) { double Epsilon = AASNutation.MeanObliquityOfEcliptic(elements.JDEquinox); double JD0 = JD; //What will be the return value AASEllipticalObjectDetails details = new AASEllipticalObjectDetails(); Epsilon = AASCoordinateTransformation.DegreesToRadians(Epsilon); double omega = AASCoordinateTransformation.DegreesToRadians(elements.omega); double w = AASCoordinateTransformation.DegreesToRadians(elements.w); double i = AASCoordinateTransformation.DegreesToRadians(elements.i); double sinEpsilon = Math.Sin(Epsilon); double cosEpsilon = Math.Cos(Epsilon); double sinOmega = Math.Sin(omega); double cosOmega = Math.Cos(omega); double cosi = Math.Cos(i); double sini = Math.Sin(i); double F = cosOmega; double G = sinOmega * cosEpsilon; double H = sinOmega * sinEpsilon; double P = -sinOmega * cosi; double Q = cosOmega * cosi * cosEpsilon - sini * sinEpsilon; double R = cosOmega * cosi * sinEpsilon + sini * cosEpsilon; double a = Math.Sqrt(F * F + P * P); double b = Math.Sqrt(G * G + Q * Q); double c = Math.Sqrt(H * H + R * R); double A = Math.Atan2(F, P); double B = Math.Atan2(G, Q); double C = Math.Atan2(H, R); double n = AASElliptical.MeanMotionFromSemiMajorAxis(elements.a); AAS3DCoordinate SunCoord = AASSun.EquatorialRectangularCoordinatesAnyEquinox(JD, elements.JDEquinox); for (int j = 0; j < 2; j++) { double M = n * (JD0 - elements.T); double E = AASKepler.Calculate(M, elements.e); E = AASCoordinateTransformation.DegreesToRadians(E); double v = 2 * Math.Atan(Math.Sqrt((1 + elements.e) / (1 - elements.e)) * Math.Tan(E / 2)); double r = elements.a * (1 - elements.e * Math.Cos(E)); double x = r * a * Math.Sin(A + w + v); double y = r * b * Math.Sin(B + w + v); double z = r * c * Math.Sin(C + w + v); if (j == 0) { details.HeliocentricRectangularEquatorial = new AAS3DCoordinate() { X = x, Y = y, Z = z }; //Calculate the heliocentric ecliptic coordinates also double u = w + v; double cosu = Math.Cos(u); double sinu = Math.Sin(u); details.HeliocentricRectangularEcliptical = new AAS3DCoordinate() { X = r * (cosOmega * cosu - sinOmega * sinu * cosi), Y = r * (sinOmega * cosu + cosOmega * sinu * cosi), Z = r * sini * sinu }; details.HeliocentricEclipticLongitude = AASCoordinateTransformation.MapTo0To360Range(AASCoordinateTransformation.RadiansToDegrees(Math.Atan2(details.HeliocentricRectangularEcliptical.Y, details.HeliocentricRectangularEcliptical.X))); details.HeliocentricEclipticLatitude = AASCoordinateTransformation.RadiansToDegrees(Math.Asin(details.HeliocentricRectangularEcliptical.Z / r)); } double psi = SunCoord.X + x; double nu = SunCoord.Y + y; double sigma = SunCoord.Z + z; double Alpha = Math.Atan2(nu, psi); Alpha = AASCoordinateTransformation.RadiansToDegrees(Alpha); double Delta = Math.Atan2(sigma, Math.Sqrt(psi * psi + nu * nu)); Delta = AASCoordinateTransformation.RadiansToDegrees(Delta); double Distance = Math.Sqrt(psi * psi + nu * nu + sigma * sigma); if (j == 0) { details.TrueGeocentricRA = AASCoordinateTransformation.MapTo0To24Range(Alpha / 15); details.TrueGeocentricDeclination = Delta; details.TrueGeocentricDistance = Distance; details.TrueGeocentricLightTime = DistanceToLightTime(Distance); } else { details.AstrometricGeocentricRA = AASCoordinateTransformation.MapTo0To24Range(Alpha / 15); details.AstrometricGeocentricDeclination = Delta; details.AstrometricGeocentricDistance = Distance; details.AstrometricGeocentricLightTime = DistanceToLightTime(Distance); double RES = Math.Sqrt(SunCoord.X * SunCoord.X + SunCoord.Y * SunCoord.Y + SunCoord.Z * SunCoord.Z); details.Elongation = Math.Acos((RES * RES + Distance * Distance - r * r) / (2 * RES * Distance)); details.Elongation = AASCoordinateTransformation.RadiansToDegrees(details.Elongation); details.PhaseAngle = Math.Acos((r * r + Distance * Distance - RES * RES) / (2 * r * Distance)); details.PhaseAngle = AASCoordinateTransformation.RadiansToDegrees(details.PhaseAngle); } if (j == 0) //Prepare for the next loop around JD0 = JD - details.TrueGeocentricLightTime; } return details; }