Beispiel #1
0
        public static AASNodeObjectDetails PassageThroAscendingNode(ref AASParabolicObjectElements elements)
        {
            double v = AASCoordinateTransformation.MapTo0To360Range(-elements.w);

            v = AASCoordinateTransformation.DegreesToRadians(v);
            double s  = Math.Tan(v / 2);
            double s2 = s * s;

            AASNodeObjectDetails details = new AASNodeObjectDetails();

            details.t      = elements.T + 27.403895 * (s2 * s + 3 * s) * elements.q * Math.Sqrt(elements.q);
            details.radius = elements.q * (1 + s2);

            return(details);
        }
Beispiel #2
0
        public static AASParabolicObjectDetails Calculate(double JD, ref AASParabolicObjectElements elements)
        {
            double Epsilon = AASNutation.MeanObliquityOfEcliptic(elements.JDEquinox);

            double JD0 = JD;

            //What will be the return value
            AASParabolicObjectDetails details = new AASParabolicObjectDetails();

            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);

            AAS3DCoordinate SunCoord = AASSun.EquatorialRectangularCoordinatesAnyEquinox(JD, elements.JDEquinox);

            for (int j = 0; j < 2; j++)
            {
                double W = 0.03649116245 / (elements.q * Math.Sqrt(elements.q)) * (JD0 - elements.T);
                double s = CalculateBarkers(W);
                double v = 2 * Math.Atan(s);
                double r = elements.q * (1 + s * s);
                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 = Math.Atan2(y, x);
                    details.HeliocentricEclipticLongitude = AASCoordinateTransformation.MapTo0To24Range(AASCoordinateTransformation.RadiansToDegrees(details.HeliocentricEclipticLongitude) / 15);
                    details.HeliocentricEclipticLatitude  = Math.Asin(z / r);
                    details.HeliocentricEclipticLatitude  = AASCoordinateTransformation.RadiansToDegrees(details.HeliocentricEclipticLatitude);
                }

                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   = AASElliptical.DistanceToLightTime(Distance);
                }
                else
                {
                    details.AstrometricGeocenticRA           = AASCoordinateTransformation.MapTo0To24Range(Alpha / 15);
                    details.AstrometricGeocentricDeclination = Delta;
                    details.AstrometricGeocentricDistance    = Distance;
                    details.AstrometricGeocentricLightTime   = AASElliptical.DistanceToLightTime(Distance);

                    double RES = Math.Sqrt(SunCoord.X * SunCoord.X + SunCoord.Y * SunCoord.Y + SunCoord.Z * SunCoord.Z);

                    details.Elongation = AASCoordinateTransformation.RadiansToDegrees(Math.Acos((RES * RES + Distance * Distance - r * r) / (2 * RES * Distance)));
                    details.PhaseAngle = AASCoordinateTransformation.RadiansToDegrees(Math.Acos((r * r + Distance * Distance - RES * RES) / (2 * r * Distance)));
                }

                if (j == 0)
                {
                    //Prepare for the next loop around
                    JD0 = JD - details.TrueGeocentricLightTime;
                }
            }

            return(details);
        }