diurnal_px.c File Reference

Correct for diurnal parallax. More...

#include <math.h>
#include <stdlib.h>
#include "aephem.h"

Functions
void	ae_diurnal_parallax (double last, double tlat, double trho, double dist, double *ra, double *dec)
	Correct for diurnal parallax. More...

Detailed Description

Correct for diurnal parallax.

Function Documentation

void ae_diurnal_parallax	(	double	last,
		double	tlat,
		double	trho,
		double	dist,
		double *	ra,
		double *	dec
	)

Correct for diurnal parallax.

See AA page D3.

This function does not bother to calculate anything unless the equatorial horizontal parallax is at least 0.005".

Parameters

last	The local apparent sidereal time, in degrees.
tlat	The geocentric latitude of the observer, in degrees.
trho	The distance from the centre of the earth to the observer, in earth radii.
dist	The earth-object distance, in AU.
ra	The right ascension of the object, in degrees; this routine modifies this parameter to correct for diurnal parallax.
dec	The declination of the object, in degrees; this routine modifies this parameter to correct for diurnal parallax.

References AE_AU, AE_DTR, AE_R_EARTH, AE_RTD, and ae_zatan2().

Referenced by ae_topocentric().