/// <summary>
        ///
        /// </summary>
        /// <param name="ra"></param>
        /// <param name="dec"></param>
        /// <param name="lat"></param>
        /// <param name="lon"></param>
        /// <param name="jd"></param>
        /// <returns></returns>
        public static structAltAz GetAltAz(double ra, double dec, double lat, double lon, double jd)
        {
            ASCOM.Astrometry.OnSurface OS = new ASCOM.Astrometry.OnSurface();
            OS.Latitude    = lat;
            OS.Longitude   = lon;
            OS.Height      = Properties.Settings.Default.site_altitude;
            OS.Temperature = Properties.Settings.Default.site_temperature;
            OS.Temperature = Properties.Settings.Default.site_pressure;

            ASCOM.Utilities.Util UT = new ASCOM.Utilities.Util();
            double JDate            = UT.DateLocalToJulian(DateTime.Now);



            double Zd   = 0.0;
            double Az   = 0.0;
            double RaR  = 0.0;
            double DecR = 0.0;

            ASCOM.Astrometry.NOVAS.NOVAS31 N = new ASCOM.Astrometry.NOVAS.NOVAS31();
            N.Equ2Hor(JDate, 0, ASCOM.Astrometry.Accuracy.Reduced, 0, 0, OS, ra, dec, ASCOM.Astrometry.RefractionOption.LocationRefraction, ref Zd, ref Az, ref RaR, ref DecR);
            //N.Equ2Hor(jd, 0, ASCOM.Astrometry.Accuracy.Reduced, 0, 0, OS, ra, dec, ASCOM.Astrometry.RefractionOption.LocationRefraction, ref Zd, ref Az, ref RaR, ref DecR);
            structAltAz ret_value = default(structAltAz);

            ret_value.Alt = 90.0 - Zd;
            ret_value.Az  = Az;
            return(ret_value);
        }
        /// <summary>
        /// </summary>
        /// <param name="RA">The right ascension in decimal value</param>
        /// <param name="Dec">The declination in decimal value</param>
        /// <param name="Lat">The latitude in decimal value</param>
        /// <param name="Long">The longitude in decimal value</param>
        /// <param name="Date">The date(time) in UTC</param>
        /// <returns>The altitude and azimuth in decimal value</returns>
        public static structAltAz Calculate(double RA, double Dec, double Lat, double Long, DateTime Date)
        {
            structAltAz ret_value = default(structAltAz);

            // Day offset and Local Siderial Time
            double dayOffset = (Date - new DateTime(2000, 1, 1, 12, 0, 0, DateTimeKind.Utc)).TotalDays;
            double LST       = (100.46 + 0.985647 * dayOffset + Long + 15 * (Date.Hour + Date.Minute / 60d) + 360) % 360;

            // Hour Angle
            double HA = (LST - RA + 360) % 360;

            // HA, DEC, Lat to Alt, AZ
            double x = Math.Cos(HA * (Math.PI / 180)) * Math.Cos(Dec * (Math.PI / 180));
            double y = Math.Sin(HA * (Math.PI / 180)) * Math.Cos(Dec * (Math.PI / 180));
            double z = Math.Sin(Dec * (Math.PI / 180));

            double xhor = x * Math.Cos((90 - Lat) * (Math.PI / 180)) - z * Math.Sin((90 - Lat) * (Math.PI / 180));
            double yhor = y;
            double zhor = x * Math.Sin((90 - Lat) * (Math.PI / 180)) + z * Math.Cos((90 - Lat) * (Math.PI / 180));

            double az  = Math.Atan2(yhor, xhor) * (180 / Math.PI) + 180;
            double alt = Math.Asin(zhor) * (180 / Math.PI);

            ret_value.Alt = alt;
            ret_value.Az  = az;

            return(ret_value);
        }
        /// <summary>
        /// Returns a struct with alt & az coordinates of an object given it's Ra & Dec from a specific lat & lon on a specific date (jd)
        /// </summary>
        /// <param name="Lat"></param>
        /// <param name="Lon"></param>
        /// <param name="Ra"></param>
        /// <param name="Dec"></param>
        /// <param name="Prof"></param>
        /// <param name="jd"></param>
        /// <returns></returns>
        public static structAltAz GetAltAz(double Lat, double Lon, double Ra, double Dec, clsSharedData Prof, double jd)
        {
            //Lat = Current Observing Latitude
            //Lon = Current Observing Longitude
            //Ra = Right Ascention of Object
            //Dec = Declination of object
            //jd = Julian Date
            //GSTime = GMT Sidereal Time


            structAltAz ret_value = default(structAltAz);
            double      ASCOMAlt  = 0;
            double      ASCOMAz   = 0;

            ASCOM.Astrometry.NOVASCOM.Site           Site      = default(ASCOM.Astrometry.NOVASCOM.Site);
            ASCOM.Utilities.Util                     utl       = default(ASCOM.Utilities.Util);
            ASCOM.Astrometry.NOVASCOM.Star           Obj       = default(ASCOM.Astrometry.NOVASCOM.Star);
            ASCOM.Astrometry.NOVASCOM.PositionVector PosVector = default(ASCOM.Astrometry.NOVASCOM.PositionVector);
            //ASCOM.Astrometry.SiteInfo Site = default(ASCOM.Astrometry.SiteInfo);
            //ASCOM.Astrometry.PosVector PVector = default(ASCOM.Astrometry.PosVector);
            ASCOM.Astrometry.NOVAS.NOVAS31 N         = new ASCOM.Astrometry.NOVAS.NOVAS31();
            ASCOM.Astrometry.SOFA.SOFA     S         = new ASCOM.Astrometry.SOFA.SOFA();
            ASCOM.Astrometry.OnSurface     onSurface = default(ASCOM.Astrometry.OnSurface);
            onSurface           = new ASCOM.Astrometry.OnSurface();
            onSurface.Latitude  = Lat;
            onSurface.Longitude = Lon;
            onSurface.Height    = Properties.Settings.Default.site_altitude;
            onSurface.Pressure  = Properties.Settings.Default.site_pressure;
            onSurface.Pressure  = Properties.Settings.Default.site_temperature;



            Site      = new ASCOM.Astrometry.NOVASCOM.Site();
            utl       = new ASCOM.Utilities.Util();
            Obj       = new ASCOM.Astrometry.NOVASCOM.Star();
            PosVector = new ASCOM.Astrometry.NOVASCOM.PositionVector();
            //Site = new ASCOM.Astrometry.SiteInfo();
            //PVector = new ASCOM.Astrometry.PosVector();



            //double jd = JDNow();
            double GSTime = GMSTime();

            Site.Latitude    = Lat;
            Site.Longitude   = Lon;
            Site.Height      = Properties.Settings.Default.site_altitude;
            Site.Pressure    = Properties.Settings.Default.site_pressure;
            Site.Temperature = Properties.Settings.Default.site_temperature;

            PosVector.SetFromSite(Site, GSTime);
            Obj.Set(Ra, Dec, 0.0, 0.0, 0.0, 0.0);
            PosVector = Obj.GetTopocentricPosition(jd, Site, false);

            ASCOMAlt = PosVector.Elevation;
            ASCOMAz  = PosVector.Azimuth;

            ret_value.Alt = ASCOMAlt;
            ret_value.Az  = ASCOMAz;

            return(ret_value);
        }