Astronomical Applications Department, U.S. Naval Observatory novas c 2 doc Page 22
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4.9
ASTRO_STAR
short int astro_star (double tjd, body *earth, cat_entry *star,
double *ra, double *dec)
PURPOSE:
Computes the astrometric place of a star, given its mean place,
proper motion, parallax, and radial velocity for J2000.0.
INPUT
ARGUMENTS:
tjd (double)
TT (or TDT) Julian date for astrometric place.
*earth (struct body)
Pointer to structure containing the body designation for the
Earth (defined in novas.h).
*star (struct cat_entry)
Pointer to catalog entry structure containing J2000.0 catalog
data with FK5-style units (defined in novas.h).
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.
RETURNED
VALUE:
(short int)
0...Everything OK.
>0...Error code from function 'solarsystem'.
Discussion:
See the discussion for function app_star. Function astro_star is identical to app_star
in input arguments and use. Here, however, the output arguments provide the astrometric
place of the star.
