LocalTime 4.5.1
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public class LocalTimeComputation {
/**
* @param args
* @throws PatriusException
* @throws URISyntaxException
* @throws IOException
*/
public static void main(String[] args) throws PatriusException, IOException, URISyntaxException {
// Patrius Dataset initialization (needed for example to get the UTC time
PatriusDataset.addResourcesFromPatriusDataset() ;
// Recovery of the UTC time scale using a "factory" (not to duplicate such unique object)
final TimeScale TUC = TimeScalesFactory.getUTC();
// Date of the orbit given in UTC time scale)
final AbsoluteDate date = new AbsoluteDate("2000-06-21T12:00:00.000", TUC);
// Getting the frame with wich will defined the orbit parameters
// As for time scale, we will use also a "factory".
final Frame CIRF = FramesFactory.getCIRF();
// Initial orbit
final double sma = 7200.e+3;
final double exc = 0.01;
final double per = sma*(1.-exc);
final double apo = sma*(1.+exc);
final double inc = FastMath.toRadians(98.);
final double pa = FastMath.toRadians(0.);
final double raan = FastMath.toRadians(90.);
final double anm = FastMath.toRadians(0.);
final double MU = Constants.WGS84_EARTH_MU;
final ApsisRadiusParameters par = new ApsisRadiusParameters(per, apo, inc, pa, raan, anm, PositionAngle.MEAN, MU);
final Orbit iniOrbit = new ApsisOrbit(par, CIRF, date);
// Sun ephemeris
CelestialBody sunEphemeris = new MeeusSun();
// Local times
LocalTimeAngle localTime = new LocalTimeAngle(sunEphemeris);
double tlt = localTime.computeTrueLocalTimeAngle(iniOrbit);
double mlt = localTime.computeMeanLocalTimeAngle(iniOrbit);
System.out.println("TLT = "+angleToHour(tlt)+" h"+" ("+FastMath.toDegrees(tlt)+" deg)");
System.out.println("MLT = "+angleToHour(mlt)+" h"+" ("+FastMath.toDegrees(mlt)+" deg)");
}
/**
* Method to transform local time given as an angle to local time in hours.
* @param angle local time as an angle (rad)
* @return local time in hours
*/
private static double angleToHour ( final double angle ) {
double hour = 12. + angle*12./FastMath.PI;
return hour;
}
}