public void NutationInObliquityTest()
{
var date = new AASDate(1987, 4, 10, 0, 0, 0, true);
double nutationInEcliptic = AASNutation.NutationInObliquity(date.Julian);
Assert.Equal(9.4425206987573933, nutationInEcliptic);
}
protected void CorrectForFK5SystemReduction()
{
double appGeoLon = GetGeocentricLongitude(vectorToEarthCorrected.x, vectorToEarthCorrected.y);
double appGeoLat = GetGeocentricLatitude(vectorToEarthCorrected.x, vectorToEarthCorrected.y, vectorToEarthCorrected.z);
double deltaLambdaFK5 = AASFK5.CorrectionInLongitude(appGeoLon, appGeoLat, jdeCorrected);
double deltaBetaFK5 = AASFK5.CorrectionInLatitude(appGeoLon, jdeCorrected);
lambdaFK5 = lambdaAberration + deltaLambdaFK5;
betaFK5 = betaAberration + deltaBetaFK5;
//correct for nutation
double deltaPhi = AASNutation.NutationInLongitude(jdeCorrected) / 3600;
double deltaEpsilon = AASNutation.NutationInObliquity(jdeCorrected) / 3600;
epsilon = AASNutation.TrueObliquityOfEcliptic(jdeCorrected);
double lambdaNutation = lambdaFK5 + deltaPhi;
double betaNutation = betaFK5 + deltaEpsilon;
//x=RA in decimal hours, y=dec in degrees
AAS2DCoordinate equatorial = AASCoordinateTransformation.Ecliptic2Equatorial(lambdaNutation, betaNutation, epsilon);
equatorialCoords.RA = new HourAngle(equatorial.X);
equatorialCoords.Declination = new DegreesAngle(equatorial.Y);
}