Solar

Functions
int LIBNOVA_EXPORT	ln_get_solar_rst_horizon (double JD, struct ln_lnlat_posn *observer, double horizon, struct ln_rst_time *rst)
	Return solar rise/set time over local horizon (specified in degrees).
int LIBNOVA_EXPORT	ln_get_solar_rst (double JD, struct ln_lnlat_posn *observer, struct ln_rst_time *rst)
	Calculate the time of rise, set and transit for the Sun.
void LIBNOVA_EXPORT	ln_get_solar_geom_coords (double JD, struct ln_helio_posn *position)
	Calculate solar geometric coordinates.
void LIBNOVA_EXPORT	ln_get_solar_equ_coords (double JD, struct ln_equ_posn *position)
	Calculate apparent equatorial coordinates.
void LIBNOVA_EXPORT	ln_get_solar_ecl_coords (double JD, struct ln_lnlat_posn *position)
	Calculate apparent ecliptical coordinates.
void LIBNOVA_EXPORT	ln_get_solar_geo_coords (double JD, struct ln_rect_posn *position)
	Calculate geocentric coordinates (rectangular)
double LIBNOVA_EXPORT	ln_get_solar_sdiam (double JD)
	Calculate the semidiameter of the Sun in arc seconds.

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Detailed Description

Calculate solar ecliptical/equatorial coordinates for a given julian date. Accuracy 0.01 arc second error - uses VSOP87 solution.

All angles are expressed in degrees.

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Function Documentation

void ln_get_solar_ecl_coords	(	double	JD,
		struct ln_lnlat_posn *	position
	)

Calculate apparent ecliptical coordinates.

Parameters:

JD	Julian day
position	Pointer to store calculated solar position.

Calculate apparent ecliptical solar coordinates for given julian day. This function includes the effects of aberration and nutation.

References ln_helio_posn::B, ln_helio_posn::L, ln_lnlat_posn::lat, ln_get_nutation(), ln_get_solar_geom_coords(), ln_lnlat_posn::lng, ln_nutation::longitude, and ln_helio_posn::R.

Referenced by ln_get_lunar_phase().

void ln_get_solar_equ_coords	(	double	JD,
		struct ln_equ_posn *	position
	)

Calculate apparent equatorial coordinates.

Parameters:

JD	Julian day
position	Pointer to store calculated solar position.

Calculate apparent equatorial solar coordinates for given julian day. This function includes the effects of aberration and nutation.

Examples:

sun.c.

References ln_helio_posn::B, ln_helio_posn::L, ln_lnlat_posn::lat, ln_get_equ_from_ecl(), ln_get_nutation(), ln_get_solar_geom_coords(), ln_lnlat_posn::lng, ln_nutation::longitude, and ln_helio_posn::R.

Referenced by ln_get_lunar_bright_limb(), and ln_get_solar_rst_horizon().

void ln_get_solar_geo_coords	(	double	JD,
		struct ln_rect_posn *	position
	)

Calculate geocentric coordinates (rectangular)

Parameters:

JD	Julian day
position	Pointer to store calculated solar position.

Calculate geocentric coordinates (rectangular) for given julian day. Accuracy 0.01 arc second error - uses VSOP87 solution. Position returned is in units of AU.

References ln_get_earth_helio_coords(), ln_get_rect_from_helio(), ln_rect_posn::X, ln_rect_posn::Y, and ln_rect_posn::Z.

Referenced by ln_get_ell_body_equ_coords(), ln_get_hyp_body_equ_coords(), and ln_get_par_body_equ_coords().

void ln_get_solar_geom_coords	(	double	JD,
		struct ln_helio_posn *	position
	)

Calculate solar geometric coordinates.

Parameters:

JD	Julian day
position	Pointer to store calculated solar position.

Calculate geometric coordinates and radius vector accuracy 0.01 arc second error - uses VSOP87 solution.

Latitude and Longitude returned are in degrees, whilst radius vector returned is in AU.

Examples:

sun.c.

References ln_helio_posn::B, ln_helio_posn::L, ln_get_earth_helio_coords(), and ln_range_degrees().

Referenced by ln_get_ecl_aber(), ln_get_jupiter_equ_coords(), ln_get_mars_equ_coords(), ln_get_mercury_equ_coords(), ln_get_neptune_equ_coords(), ln_get_pluto_equ_coords(), ln_get_saturn_equ_coords(), ln_get_solar_ecl_coords(), ln_get_solar_equ_coords(), ln_get_uranus_equ_coords(), and ln_get_venus_equ_coords().

double ln_get_solar_rst	(	double	JD,
		struct ln_lnlat_posn *	observer,
		struct ln_rst_time *	rst
	)

Calculate the time of rise, set and transit for the Sun.

Calls get_solar_rst_horizon with horizon set to LN_SOLAR_STANDART_HORIZON.

Examples:

sun.c.

References ln_get_solar_rst_horizon().

double ln_get_solar_sdiam

(

double

JD

)

Calculate the semidiameter of the Sun in arc seconds.

Parameters:

JD	Julian day

Returns:

Semidiameter in arc seconds

Calculate the semidiameter of the Sun in arc seconds for the given julian day.

References ln_get_earth_solar_dist().