Package org.orekit.models.earth

Class EarthStandardAtmosphereRefraction

java.lang.Object
org.orekit.models.earth.EarthStandardAtmosphereRefraction
All Implemented Interfaces:
Serializable, AtmosphericRefractionModel
public class EarthStandardAtmosphereRefraction extends Object implements AtmosphericRefractionModel
Implementation of refraction model for Earth standard atmosphere.

Refraction angle is 0 at zenith, about 1 arcminute at 45°, and 34 arcminutes at the horizon for optical wavelengths.

Refraction angle is computed according to Saemundssen formula quoted by Meeus. For reference, see Astronomical Algorithms (1998), 2nd ed, (ISBN 0-943396-61-1), chap. 15.

This formula is about 30 arcseconds of accuracy very close to the horizon, as variable atmospheric effects become very important.

Local pressure and temperature can be set to correct refraction at the viewpoint.

Since:
6.1
See Also:

  • Field Details

    • DEFAULT_CORRECTION_FACTOR

      public static final double DEFAULT_CORRECTION_FACTOR
      Default correction factor value.
      See Also:

    • DEFAULT_PRESSURE

      public static final double DEFAULT_PRESSURE
      Default local pressure at viewpoint (Pa).
      See Also:

    • DEFAULT_TEMPERATURE

      public static final double DEFAULT_TEMPERATURE
      Default local temperature at viewpoint (K).
      See Also:

    • STANDARD_ATM_PRESSURE

      public static final double STANDARD_ATM_PRESSURE
      NIST standard atmospheric pressure (Pa).
      See Also:

    • STANDARD_ATM_TEMPERATURE

      public static final double STANDARD_ATM_TEMPERATURE
      NIST standard atmospheric temperature (K).
      See Also:

  • Constructor Details

    • EarthStandardAtmosphereRefraction

      public EarthStandardAtmosphereRefraction()
      Creates a new default instance.

    • EarthStandardAtmosphereRefraction

      public EarthStandardAtmosphereRefraction(double pressure, double temperature)
      Creates an instance given a specific pressure and temperature.
      Parameters:
      pressure - in Pascals (Pa)
      temperature - in Kelvin (K)

  • Method Details

    • getPressure

      public double getPressure()
      Get the local pressure at the evaluation location.
      Returns:
      the pressure (Pa)

    • setPressure

      public void setPressure(double pressure)
      Set the local pressure at the evaluation location

      Otherwise the default value for the local pressure is set to DEFAULT_PRESSURE.

      Parameters:
      pressure - the pressure to set (Pa)

    • getTemperature

      public double getTemperature()
      Get the local temperature at the evaluation location.
      Returns:
      the temperature (K)

    • setTemperature

      public void setTemperature(double temperature)
      Set the local temperature at the evaluation location

      Otherwise the default value for the local temperature is set to DEFAULT_TEMPERATURE.

      Parameters:
      temperature - the temperature to set (K)

    • getRefraction

      public double getRefraction(double trueElevation)
      Description copied from interface: AtmosphericRefractionModel
      Compute the refraction angle from the true (geometrical) elevation.
      Specified by:
      getRefraction in interface AtmosphericRefractionModel
      Parameters:
      trueElevation - true elevation (rad)
      Returns:
      refraction angle (rad)