net.time4j.calendar.astro

Class SunPosition

java.lang.Object

net.time4j.calendar.astro.SunPosition

All Implemented Interfaces:

Serializable, EquatorialCoordinates

public class SunPosition
extends Object
implements EquatorialCoordinates, Serializable

Contains methods for calculating the position of the sun.

The position refers to the gemometric center of the sun.

Since:

3.38/4.33

Author:

Meno Hochschild

See Also:

Serialized Form

Method Summary

Modifier and Type	Method and Description
static SunPosition	at(Moment moment, GeoLocation location) Calculates the position of sun at given moment and geographical location.
boolean	equals(Object obj)
double	getAzimuth() Obtains the azimuth of sun in degrees (compass orientation).
double	getDeclination() Obtains the declination in degrees.
double	getElevation() Obtains the elevation of sun relative to the horizon in degrees.
double	getRightAscension() Obtains the right ascension in degrees.
double	getShadowLength(double objectHeight) Determines the length of shadow casted by an object of given height.
int	hashCode()
static Zodiac.Event	inConstellationOf(Zodiac zodiac) Determines the event when the sun enters or exits given zodiac constellation.
static Zodiac.Event	inSignOf(Zodiac zodiac) Determines the event when the sun enters or exits given zodiac sign (for horoscope purpose).
String	toString()

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface net.time4j.calendar.astro.EquatorialCoordinates

getRightAscensionHMS

Method Detail

at

public static SunPosition at(Moment moment,
                             GeoLocation location)

Calculates the position of sun at given moment and geographical location.

Parameters:

moment - the time when the position of sun is to be determined

location - geographical location of observer

Returns:

sun position

inConstellationOf

public static Zodiac.Event inConstellationOf(Zodiac zodiac)

Determines the event when the sun enters or exits given zodiac constellation.

Parameters:

zodiac - the astronomical zodiac constellation defined by IAU

Returns:

event when the sun enters or leaves the zodiac constellation

Since:

4.37

inSignOf

public static Zodiac.Event inSignOf(Zodiac zodiac)

Determines the event when the sun enters or exits given zodiac sign (for horoscope purpose).

Parameters:

zodiac - the astronomical zodiac sign

Returns:

event when the sun enters or leaves the zodiac sign

Throws:

IllegalArgumentException - if the zodiac is Zodiac.OPHIUCHUS

Since:

4.37

getRightAscension

public double getRightAscension()

Description copied from interface: EquatorialCoordinates

Obtains the right ascension in degrees.

Specified by:

getRightAscension in interface EquatorialCoordinates

Returns:

double in range 0-360

getDeclination

public double getDeclination()

Description copied from interface: EquatorialCoordinates

Obtains the declination in degrees.

Specified by:

getDeclination in interface EquatorialCoordinates

Returns:

double

getAzimuth

public double getAzimuth()

Obtains the azimuth of sun in degrees (compass orientation).

The azimuth is the result of a coordinate transformation of right ascension and declination to the horizon system.

Returns:

azimuth in degrees measured from the north (compass orientation)

getElevation

public double getElevation()

Obtains the elevation of sun relative to the horizon in degrees.

The elevation is the result of a coordinate transformation of right ascension and declination to the horizon system.

Returns:

elevation in degrees (positive if above the horizon and negative if below the horizon)

getShadowLength

public double getShadowLength(double objectHeight)

Determines the length of shadow casted by an object of given height.

If the sun is at or below the horizon then the length of shadow is positive infinity.

Parameters:

objectHeight - the height of object in meters

Returns:

length of shadow in meters (or positive infinity)

Throws:

IllegalArgumentException - if the object height is not finite and positive

Since:

3.40/4.35

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Overrides:

toString in class Object