THIS SUBROUTINE RETURNS THE LOCATION OF THE CELESTIAL
INTERMEDIATE ORIGIN (CIO) FOR A GIVEN JULIAN DATE, AS A
RIGHT ASCENSION WITH RESPECT TO EITHER THE GCRS (GEOCENTRIC ICRS)
ORIGIN OR THE TRUE EQUINOX OF DATE. THE CIO IS ALWAYS LOCATED ON
THE TRUE EQUATOR (=INTERMEDIATE EQUATOR) OF DATE.
TJD = TDB JULIAN DATE (IN)
RACIO = RIGHT ASCENSION OF THE CIO, IN HOURS (OUT)
K = REFERENCE SYSTEM IN WHICH RIGHT ASCENSION IS
GIVEN (OUT)
K=1 MEANS GCRS
K=2 MEANS TRUE EQUATOR AND EQUINOX OF DATE
NOTE: IF AN EXTERNAL FILE OF CIO RIGHT ASCENSIONS IS AVAILABLE,
IT WILL BE USED AND K WILL BE SET TO 1. OTHERWISE AN INTERNAL
COMPUTATION WILL BE USED AND K WILL BE SET TO 2.
Nodes of different colours represent the following:
Solid arrows point from a procedure to one which it calls. Dashed
arrows point from an interface to procedures which implement that interface.
This could include the module procedures in a generic interface or the
implementation in a submodule of an interface in a parent module.
Nodes of different colours represent the following:
Solid arrows point from a procedure to one which it calls. Dashed
arrows point from an interface to procedures which implement that interface.
This could include the module procedures in a generic interface or the
implementation in a submodule of an interface in a parent module.