//static void AltAzToRaDec2(double alt, double az, out double hrAngle, out double dec, double lat)
//{
// if (alt == 0)
// {
// alt = .00000000001;
// }
// if (az == 0)
// {
// az = .00000000001;
// }
// double sin_dec;
// double cos_lat = Math.Cos(lat);
// if (alt > Math.PI / 2.0)
// {
// alt = Math.PI - alt;
// az += Math.PI;
// }
// if (alt < -Math.PI / 2.0)
// {
// alt = -Math.PI - alt;
// az -= Math.PI;
// }
// sin_dec = Math.Sin(lat) * Math.Sin(alt) + cos_lat * Math.Cos(alt) * Math.Cos(az);
// dec = Math.Asin(sin_dec);
// if (cos_lat < .00001)
// {
// hrAngle = az + Math.PI;
// }
// else
// {
// double cos_lat_cos_dec = (cos_lat * Math.Cos(dec));
// double sin_alt_sinLat_sin_dec = Math.Sin(alt) - Math.Sin(lat) * sin_dec;
// double acosTarget = sin_alt_sinLat_sin_dec / cos_lat_cos_dec;
// double temp = 0;
// if (Math.Abs(acosTarget) < 1.1)
// {
// if (acosTarget > 1)
// {
// acosTarget = 1.0;
// }
// if (acosTarget < -1)
// {
// acosTarget = -1.0;
// }
// temp = Math.Acos(acosTarget);
// }
// else
// {
// temp = Math.PI;
// }
// //if (double.IsNaN(temp))
// //{
// // temp = Math.PI;
// //}
// if (Math.Sin(az) > 0.0)
// {
// hrAngle = Math.PI - temp;
// }
// else
// {
// hrAngle = Math.PI + temp;
// }
// }
//}
public static double MstFromUTC2(Date utc, double lng)
{
int year = utc.GetUTCFullYear();
int month = utc.GetUTCMonth()+1;
int day = utc.GetUTCDate();
int hour = utc.GetUTCHours();
int minute = utc.GetUTCMinutes();
double second = utc.GetUTCSeconds() + utc.GetUTCMilliseconds() / 1000.0;
if (month == 1 || month == 2)
{
year -= 1;
month += 12;
}
int a = (int)(year / 100);
int b = 2 - a + (int)Math.Floor((double)(a / 4.0));
int c = (int)Math.Floor(365.25 * year);
int d = (int)Math.Floor(30.6001 * (month + 1));
double julianDays;
double jd2;
double julianCenturies;
double mst;
julianDays = b + c + d - 730550.5 + day + (hour + minute / 60.00 + second / 3600.00) / 24.00;
julianCenturies = julianDays / 36525.0d;
mst = 280.46061837 + 360.98564736629d * julianDays + 0.000387933d * julianCenturies * julianCenturies - julianCenturies * julianCenturies * julianCenturies / 38710000 + lng;
if (mst > 0.0)
{
while (mst > 360.0)
{
mst = mst - 360.0;
}
}
else
{
while (mst < 0.0)
{
mst = mst + 360.0;
}
}
return mst;
}
public static double UtcToJulian(Date utc)
{
int year = utc.GetUTCFullYear();
int month = utc.GetUTCMonth()+1;
double day = utc.GetUTCDate();
double hour = utc.GetUTCHours();
double minute = utc.GetUTCMinutes();
double second = utc.GetUTCSeconds() + utc.GetUTCMilliseconds() / 1000.0;
double dblDay = day + (hour / 24.0) + (minute / 1440.0) + (second / 86400.0);
return AstroCalc.GetJulianDay(year, month, dblDay);
//return DateToJD(year, month, dblDay, true);
//return julianDays;
}
