/// <summary>
/// Угол наклона эклиптики к экватору.
/// </summary>
///
/// <param name="julianDate"> Юлианская дата.</param>
///
/// <returns>
/// Угол наклона эклиптики к экватору.
/// </returns>
private static double GetEps0(double julianDate)
{
double eps0 = 0, deps = 0;
IAUSOFA.iauNut06a(Date.J2000, julianDate - Date.J2000, ref eps0, ref deps);
// из iauP06e
return(84381.406 * IAUSOFA.DAS2R + deps);
}
/// <summary>
/// Положение и скорость Нептуна.
/// </summary>
///
/// <param name="julianDate"> Юлианская дата.</param>
///
/// <returns>
/// Положение и скорость Нептуна.
/// </returns>
private static (Vector Vector, Vector Velocity, Basis Basis) NeptuneParams(double julianDate)
{
var pv = new double[2, 3];
IAUSOFA.iauPlan94(Date.J2000, julianDate - Date.J2000, 8, pv);
var vector = new Vector(pv[0, 0], pv[0, 1], pv[0, 2]);
var velocity = new Vector(pv[1, 0], pv[1, 1], pv[1, 2]);
return(vector * IAUSOFA.DAU, velocity *IAUSOFA.DAU / Date.JD_TO_SECOND, new Basis());
}
/// <summary>
/// Положение и скорость невращающейся Земли.
/// </summary>
///
/// <param name="julianDate"> Юлианская дата.</param>
///
/// <returns>
/// Положение и скорость невращающейся Земли.
/// </returns>
private static (Vector Vector, Vector Velocity, Basis Basis) EarthParams(double julianDate)
{
var pvh = new double[2, 3];
var pvb = new double[2, 3];
IAUSOFA.iauEpv00(Date.J2000, julianDate - Date.J2000, pvh, pvb);
var vector = new Vector(pvh[0, 0], pvh[0, 1], pvh[0, 2]);
var velocity = new Vector(pvh[1, 0], pvh[1, 1], pvh[1, 2]);
return(vector * IAUSOFA.DAU, velocity *IAUSOFA.DAU / Date.JD_TO_SECOND, new Basis());
}
/// <summary>
/// Положение и скорость Луны.
/// </summary>
///
/// <param name="julianDate"> Юлианская дата.</param>
///
/// <returns>
/// Положение и скорость Луны.
/// </returns>
private static (Vector Vector, Vector Velocity, Basis Basis) MoonParams(double julianDate)
{
(Vector EarthVector, Vector EarthVelocity, Basis basis) = EarthParams(julianDate);
var pv = new double[2, 3];
IAUSOFA.iauPlan94(Date.J2000, julianDate - Date.J2000, 3, pv);
Vector EMBVector = new Vector(pv[0, 0], pv[0, 1], pv[0, 2]) * IAUSOFA.DAU;
Vector EMBVelocity = new Vector(pv[1, 0], pv[1, 1], pv[1, 2]) * IAUSOFA.DAU / Date.JD_TO_SECOND;
return(new Vector((EMBVector * (earth.Mass + moon.Mass) - EarthVector * earth.Mass) / moon.Mass - EarthVector),
new Vector((EMBVelocity * (earth.Mass + moon.Mass) - EarthVelocity * earth.Mass) / moon.Mass - EarthVelocity),
basis);
}
