public void EquatorialToHorizontal()
{
// Apparent equatorial coordinates of Venus
var eq = new CrdsEquatorial(new HMS("23h 09m 16.641s"), new DMS("-6* 43' 11.61''"));
// Geographical coordinates of US Naval Observatory at Washington, DC
var geo = new CrdsGeographical(new DMS("+38* 55' 17''"), new DMS("+77* 03' 56''"));
// Date of observation
var jd = new Date(new DateTime(1987, 4, 10, 19, 21, 0, DateTimeKind.Utc)).ToJulianDay();
// Mean sidereal time at Greenwich
var theta0 = Date.MeanSiderealTime(jd);
Assert.AreEqual(new HMS("8h 34m 57.0896s"), new HMS(theta0));
// Nutation elements
var nutation = Nutation.NutationElements(jd);
// True obliquity
var epsilon = Date.TrueObliquity(jd, nutation.deltaEpsilon);
// Apparent sidereal time at Greenwich
theta0 = Date.ApparentSiderealTime(jd, nutation.deltaPsi, epsilon);
Assert.AreEqual(new HMS("8h 34m 56.853s"), new HMS(theta0));
// Expected local horizontal coordinates of Venus
var hor = eq.ToHorizontal(geo, theta0);
Assert.AreEqual(15.1249, hor.Altitude, 1e-4);
Assert.AreEqual(68.0336, hor.Azimuth, 1e-4);
}
/// <inheritdoc/>
public ICollection <CrdsGeographical> Search(CrdsGeographical center, float radius)
{
if (isLoaded)
{
lock (locker)
{
return(allLocations.Where(c => c.DistanceTo(center) <= radius).Select(c =>
{
return new CrdsGeographical()
{
CountryCode = c.Country,
Elevation = c.Elevation,
Latitude = c.Latitude,
Longitude = c.Longitude,
LocationName = c.Names.FirstOrDefault(),
TimeZoneId = c.TimeZone?.TimeZoneId,
UtcOffset = c.TimeZone?.UtcOffset ?? 0
};
}).ToArray());
}
}
else
{
return(new CrdsGeographical[0]);
}
}
public void HorizontalToEquatorial()
{
// Apparent local horizontal coordinates of Venus
var hor = new CrdsHorizontal(68.0337, 15.1249);
// Geographical coordinates of US Naval Observatory at Washington, DC
var geo = new CrdsGeographical(new DMS("+38* 55' 17''"), new DMS("+77* 03' 56''"));
// Date of observation
var jd = new Date(new DateTime(1987, 4, 10, 19, 21, 0, DateTimeKind.Utc)).ToJulianDay();
// Nutation elements
var nutation = Nutation.NutationElements(jd);
// True obliquity
var epsilon = Date.TrueObliquity(jd, nutation.deltaEpsilon);
// Apparent sidereal time at Greenwich
var theta0 = Date.ApparentSiderealTime(jd, nutation.deltaPsi, epsilon);
Assert.AreEqual(new HMS("8h 34m 56.853s"), new HMS(theta0));
// Expected apparent equatorial coordinates of Venus
var eqExpected = new CrdsEquatorial(new HMS("23h 09m 16.641s"), new DMS("-6* 43' 11.61''"));
// Tested value
var eqActual = hor.ToEquatorial(geo, theta0);
Assert.AreEqual(eqExpected.Alpha, eqActual.Alpha, errorInHMS);
Assert.AreEqual(eqExpected.Delta, eqActual.Delta, errorInDMS);
}
public ContactsTableItem(string text, double jd, CrdsGeographical g = null)
{
Point = text;
Coordinates = g != null?Format.Geo.Format(g) : null;
Time = $"{Format.Time.Format(new Date(jd, 0))} {(!double.IsNaN(jd) ? "UTC" : "")}";
}
/// <inheritdoc/>
public void SetLocation(CrdsGeographical geo)
{
try
{
lock (locker)
{
if (telescope != null)
{
telescope.SiteLongitude = geo.Longitude;
telescope.SiteLatitude = geo.Latitude;
telescope.SiteElevation = geo.Elevation;
}
}
}
catch (Exception ex)
{
RaiseOnMessageShow("$Ascom.Messages.UnableSetLocation");
Log.Error($"Unable to set telescope observation place: {ex}");
}
}
public void ToTopocentric()
{
// Geocentric coordinates of Mars
CrdsEquatorial eq = new CrdsEquatorial(339.530208, -15.771083);
// Palomar Observatory coordinates, see example 11.a
CrdsGeographical geo = new CrdsGeographical(new HMS("7h 47m 27s").ToDecimalAngle(), new DMS("+33* 21' 22''").ToDecimalAngle(), 1706);
// Equatoria horizontal parallax
double pi = 23.592 / 3600;
// Apparent sidereal time at Greenwich
double theta0 = new HMS("1h 40m 45s").ToDecimalAngle();
// Equatorial topocentric coordinates of Mars
CrdsEquatorial topo = eq.ToTopocentric(geo, theta0, pi);
Assert.AreEqual(new HMS("22h 38m 08.54s").ToDecimalAngle(), topo.Alpha, errorInHMS);
Assert.AreEqual(new DMS("-15* 46' 30.04''").ToDecimalAngle(), topo.Delta, errorInDMS);
}
public void RiseTransitSet()
{
// Venus at Boston, 20 March 1988
{
CrdsEquatorial[] eq = new CrdsEquatorial[]
{
new CrdsEquatorial(new HMS("02h 46m 25.086s"), new DMS("+18° 23' 36.14''")),
new CrdsEquatorial(new HMS("02h 48m 31.193s"), new DMS("+18° 35' 16.41''")),
new CrdsEquatorial(new HMS("02h 50m 37.273s"), new DMS("+18° 46' 50.47''"))
};
CrdsGeographical location = new CrdsGeographical(71.0833, 42.3333);
var rts = Visibility.RiseTransitSet(eq, location, 177.74208, 0, 0);
// 2 minute error
const double error = 2.0 / (24 * 60);
Assert.AreEqual(new TimeSpan(12, 27, 0).TotalDays, rts.Rise, error);
Assert.AreEqual(new TimeSpan(19, 39, 0).TotalDays, rts.Transit, error);
Assert.AreEqual(new TimeSpan(02, 50, 0).TotalDays, rts.Set, error);
}
// Antares at Boston, 20 March 1988
{
var eq = new CrdsEquatorial(new HMS("16h 28m 41s"), new DMS("-26° 24' 30''"));
CrdsGeographical location = new CrdsGeographical(71.0833, 42.3333);
var rts = Visibility.RiseTransitSet(eq, location, 177.74208);
// 2 minute error
const double error = 2.0 / (24 * 60);
Assert.AreEqual(new TimeSpan(05, 07, 0).TotalDays, rts.Rise, error);
Assert.AreEqual(new TimeSpan(09, 19, 0).TotalDays, rts.Transit, error);
Assert.AreEqual(new TimeSpan(13, 31, 0).TotalDays, rts.Set, error);
}
}
public void ProjectionTests()
{
{
double d = 15.32558;
double mu = 345.88554;
CrdsGeographical g = new CrdsGeographical(-26.71875, 44.66865);
Vector v = SolarEclipses.ProjectOnFundamentalPlane(g, d, mu);
CrdsGeographical g0 = SolarEclipses.ProjectOnEarth(new System.Drawing.PointF((float)v.X, (float)v.Y), d, mu);
Assert.AreEqual(g.Latitude, g0.Latitude, 1e-5);
Assert.AreEqual(g.Longitude, g0.Longitude, 1e-5);
}
{
double d = -23.25608;
double mu = 48.57292;
CrdsGeographical g = new CrdsGeographical(97.20703, -28.22697);
Vector v = SolarEclipses.ProjectOnFundamentalPlane(g, d, mu);
CrdsGeographical g0 = SolarEclipses.ProjectOnEarth(new System.Drawing.PointF((float)v.X, (float)v.Y), d, mu);
Assert.AreEqual(g.Latitude, g0.Latitude, 1e-5);
Assert.AreEqual(g.Longitude, g0.Longitude, 1e-5);
}
}
/// <summary>
/// Creates new instance of <see cref="LocationVM"/>
/// </summary>
public LocationVM(ISky sky, ISettings settings)
{
CrdsEquatorial eqSun = SolarEphem.Ecliptical(sky.Context.JulianDay).ToEquatorial(sky.Context.Epsilon);
ObserverLocation = new CrdsGeographical(sky.Context.GeoLocation);
SunHourAngle = Coordinates.HourAngle(sky.Context.SiderealTime, 0, eqSun.Alpha);
SunDeclination = eqSun.Delta;
IsNightMode = settings.Get <ColorSchema>("Schema") == ColorSchema.Red;
OkCommand = new Command(Ok);
CancelCommand = new Command(Close);
EndSearchModeCommand = new Command(EndSearchMode);
SelectLocationCommand = new Command(SelectLocation);
string line;
string filePath = Path.Combine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), "Data", "TimeZones.dat");
using (StreamReader file = new StreamReader(filePath))
{
while ((line = file.ReadLine()) != null)
{
// skip first and empty lines
if (line.StartsWith("CountryCode") ||
string.IsNullOrWhiteSpace(line))
{
continue;
}
string[] chunks = line.Split('\t');
TimeZones.Add(new TimeZoneItem()
{
TimeZoneId = chunks[1], UtcOffset = double.Parse(chunks[4], CultureInfo.InvariantCulture)
});
}
file.Close();
}
}
public void Separation()
{
// Example 17.a, AA(II)
{
var c1 = new CrdsEquatorial(213.9154, 19.1825);
var c2 = new CrdsEquatorial(201.2983, -11.1614);
Assert.AreEqual(32.7930, Angle.Separation(c1, c2), 1e-4);
}
{
var c1 = new CrdsEcliptical(213.9154, 19.1825);
var c2 = new CrdsEcliptical(201.2983, -11.1614);
Assert.AreEqual(32.7930, Angle.Separation(c1, c2), 1e-4);
}
{
var c1 = new CrdsGeographical(213.9154, 19.1825);
var c2 = new CrdsGeographical(201.2983, -11.1614);
Assert.AreEqual(32.7930, Angle.Separation(c1, c2), 1e-4);
}
{
var c1 = new CrdsHorizontal(213.9154, 19.1825);
var c2 = new CrdsHorizontal(201.2983, -11.1614);
Assert.AreEqual(32.7930, Angle.Separation(c1, c2), 1e-4);
}
}
public SkyContext(double jd, CrdsGeographical location, bool preferFast)
{
PreferFastCalculation = preferFast;
GeoLocation = location;
JulianDay = jd;
}
public double DistanceTo(CrdsGeographical g)
{
return(g.DistanceTo(new CrdsGeographical(Longitude, Latitude)));
}
public SkyContext(double jd, CrdsGeographical location) : this(jd, location, false)
{
}
public void SetLocation(CrdsGeographical geo)
{
}
public async Task SetDate(Date date, CrdsGeographical geoLocation)
{
await Task.Run(() =>
{
double jd0 = date.ToJulianEphemerisDay();
daysInMonth = Date.DaysInMonth(date.Year, date.Month);
var eL = new PointF[5];
var eB = new PointF[5];
var eR = new PointF[5];
var jL = new PointF[5];
var jB = new PointF[5];
var jR = new PointF[5];
var earth = new CrdsHeliocentrical[5];
var jupiter = new CrdsHeliocentrical[5];
// calculate heliocentrical positions of Earth and Jupiter for 5 instants
// and find least squares approximation model of planets position
// to quick calculation of Galilean moons postions.
for (int i = 0; i < 5; i++)
{
double jd = jd0 + (i / 4.0) * daysInMonth;
earth[i] = PlanetPositions.GetPlanetCoordinates(3, jd);
jupiter[i] = PlanetPositions.GetPlanetCoordinates(5, jd);
}
double[] earthL = earth.Select(x => x.L).ToArray();
double[] earthB = earth.Select(x => x.B).ToArray();
double[] earthR = earth.Select(x => x.R).ToArray();
double[] jupiterL = jupiter.Select(x => x.L).ToArray();
double[] jupiterB = jupiter.Select(x => x.B).ToArray();
double[] jupiterR = jupiter.Select(x => x.R).ToArray();
// it's important to align longitudes (avoid 0 degrees crossing)
// before applying least squares method
earthL = Angle.Align(earthL);
jupiterL = Angle.Align(jupiterL);
for (int i = 0; i < 5; i++)
{
eL[i] = new PointF(i, (float)earthL[i]);
eB[i] = new PointF(i, (float)earthB[i]);
eR[i] = new PointF(i, (float)earthR[i]);
jL[i] = new PointF(i, (float)jupiterL[i]);
jB[i] = new PointF(i, (float)jupiterB[i]);
jR[i] = new PointF(i, (float)jupiterR[i]);
}
Begin = jd0;
End = jd0 + daysInMonth;
GeoLocation = geoLocation;
this.eL = LeastSquares.FindCoeffs(eL, 3);
this.eB = LeastSquares.FindCoeffs(eB, 3);
this.eR = LeastSquares.FindCoeffs(eR, 3);
this.jL = LeastSquares.FindCoeffs(jL, 3);
this.jB = LeastSquares.FindCoeffs(jB, 3);
this.jR = LeastSquares.FindCoeffs(jR, 3);
});
}
/// <summary>
/// Selects a location from the search results and ends the search mode
/// </summary>
private void SelectLocation()
{
_SavedLocation = new CrdsGeographical(ObserverLocation);
EndSearchMode();
}
private void DoTest(CrdsGeographical location, OrbitalElements oe, string testData, double errorR, double errorEq)
{
Regex regex = new Regex("^(\\S+)\\s+(\\S+)\\s+(\\S+)\\s+(\\S+)\\s+(\\S+ \\S+ \\S+) (\\S+ \\S+ \\S+)$");
string[] lines = testData.Split('\n');
foreach (string line in lines)
{
string dataLine = line.Trim();
if (!string.IsNullOrEmpty(dataLine))
{
var match = regex.Match(dataLine);
double jd = double.Parse(match.Groups[1].Value, CultureInfo.InvariantCulture);
double X = double.Parse(match.Groups[2].Value, CultureInfo.InvariantCulture);
double Y = double.Parse(match.Groups[3].Value, CultureInfo.InvariantCulture);
double Z = double.Parse(match.Groups[4].Value, CultureInfo.InvariantCulture);
string ra = match.Groups[5].Value;
string dec = match.Groups[6].Value;
var eqTest = new CrdsEquatorial(new HMS(ra), new DMS(dec));
var nutation = Nutation.NutationElements(jd);
var aberration = Aberration.AberrationElements(jd);
// True obliquity
double epsilon = Date.TrueObliquity(jd, nutation.deltaEpsilon);
// final difference to stop iteration process, 1 second of time
double deltaTau = TimeSpan.FromSeconds(1).TotalDays;
// time taken by the light to reach the Earth
double tau = 0;
// previous value of tau to calculate the difference
double tau0 = 1;
// Rectangular coordinates of minor body
CrdsRectangular r = null;
// Rectangular coordinates of the Sun
var sun = SunRectangular(jd, epsilon);
// Distance to the Earth
double Delta = 0;
// Iterative process to find rectangular coordinates of minor body
while (Math.Abs(tau - tau0) > deltaTau)
{
// Rectangular coordinates of minor body
r = MinorBodyPositions.GetRectangularCoordinates(oe, jd - tau, epsilon);
double ksi = sun.X + r.X;
double eta = sun.Y + r.Y;
double zeta = sun.Z + r.Z;
// Distance to the Earth
Delta = Math.Sqrt(ksi * ksi + eta * eta + zeta * zeta);
tau0 = tau;
tau = PlanetPositions.LightTimeEffect(Delta);
}
// Test heliocentric rectangular coordinates
Assert.AreEqual(X, r.X, errorR);
Assert.AreEqual(Y, r.Y, errorR);
Assert.AreEqual(Z, r.Z, errorR);
double x = sun.X + r.X;
double y = sun.Y + r.Y;
double z = sun.Z + r.Z;
double alpha = Angle.ToDegrees(Math.Atan2(y, x));
double delta = Angle.ToDegrees(Math.Asin(z / Delta));
var eq0 = new CrdsEquatorial(alpha, delta);
var theta0 = Date.ApparentSiderealTime(jd, nutation.deltaPsi, epsilon);
var parallax = PlanetEphem.Parallax(Delta);
var eq = eq0.ToTopocentric(location, theta0, parallax);
// Test equatorial coordinates
Assert.AreEqual(eqTest.Alpha, eq.Alpha, errorEq / 3600.0);
Assert.AreEqual(eqTest.Delta, eq.Delta, errorEq / 3600.0);
}
}
}
public void Noumenia()
{
// Example are taken from
// http://www.makkahcalendar.org/en/islamicCalendarArticle4.php
// IX.4 Example of Makkah
{
// 17 Nov 2009, "best time" is 14:48 UTC
double jd = new Date(new DateTime(2009, 11, 17, 14, 48, 0, DateTimeKind.Utc)).ToJulianEphemerisDay();
// Nutation elements
var nutation = Nutation.NutationElements(jd);
// True obliquity
var epsilon = Date.TrueObliquity(jd, nutation.deltaEpsilon);
// Sidereal time at Greenwich
double siderealTime = Date.ApparentSiderealTime(jd, nutation.deltaPsi, epsilon);
// Ecliptical coordinates of the Sun, taken from the example (see ref.)
CrdsEcliptical eclSun = new CrdsEcliptical(235.39, 0);
// Ecliptical coordinates of the Moon, taken from the example (see ref.)
CrdsEcliptical eclMoon = new CrdsEcliptical(245.01, -3.76);
// Geograhical coordinates of Makkah
CrdsGeographical geo = new CrdsGeographical(-39.82563, 21.42664);
double q = LunarEphem.CrescentQ(eclMoon, eclSun, 0.2539 * 3600, epsilon, siderealTime, geo);
Assert.AreEqual(-0.465, q, 0.001);
}
// IX.5 Example of intermediate horizon 30°W, 30°S at 21:04
{
// 17 Nov 2009, 21:04 UTC
double jd = new Date(new DateTime(2009, 11, 17, 21, 04, 0, DateTimeKind.Utc)).ToJulianEphemerisDay();
// Nutation elements
var nutation = Nutation.NutationElements(jd);
// True obliquity
var epsilon = Date.TrueObliquity(jd, nutation.deltaEpsilon);
// Sidereal time at Greenwich
double siderealTime = Date.ApparentSiderealTime(jd, nutation.deltaPsi, epsilon);
// Ecliptical coordinates of the Sun, taken from the example (see ref.)
CrdsEcliptical eclSun = new CrdsEcliptical(235.65, 0);
// Ecliptical coordinates of the Moon, taken from the example (see ref.)
CrdsEcliptical eclMoon = new CrdsEcliptical(248.32, -3.55);
// Geograhical coordinates of Makkah
CrdsGeographical geo = new CrdsGeographical(30, -30);
double q = LunarEphem.CrescentQ(eclMoon, eclSun, 0.2536 * 3600, epsilon, siderealTime, geo);
Assert.AreEqual(0.367, q, 0.001);
}
}
/// <summary>
/// Creates new point with Julian Day value and coordinates
/// </summary>
/// <param name="jd">Julian Day value</param>
/// <param name="c">Coordinates of the point</param>
public SolarEclipseMapPoint(double jd, CrdsGeographical c) : base(c)
{
JulianDay = jd;
}
