Astronomical Applications Department, U.S. Naval Observatory - NOVASC (Page 16)

ASTRO_PLANET

short int astro_planet (double tjd, short int planet, short int earth,

double *ra, double *dec, double *dis)

PURPOSE:
Computes the astrometric place of a planet or other solar system
body.

INPUT
ARGUMENTS:
tjd (double)
TDT Julian date for calculation.
planet (short int)
Body identification number for desired planet.
earth (short int)
Body identification number for the Earth.

OUTPUT
ARGUMENTS:
*ra (double)
Astrometric right ascension in hours, referred to mean equator
and equinox of J2000.
*dec (double)
Astrometric declination in degrees, referred to mean equator
and equinox of J2000.
*dis (double)
True distance from Earth to planet in AU.

RETURNED
VALUE:
(short int)
0...Everything OK.
>0...Error code from function 'solarsystem'.

Discussion:

See the discussion for function app_planet. Function astro_planet is identical to app_planet in input

arguments and use. Here, however, the output arguments provide the astrometric place of the planet.