THIS SUBROUTINE CONVERTS RIGHT ASCENSION AND DECLINATION TO ECLIPTIC LONGITUDE AND LATITUDE.
TJD = TT JULIAN DATE OF EQUATOR, EQUINOX, AND ECLIPTIC
USED FOR COORDINATES (IN)
ICOORD = COORDINATE SYSTEM SELECTION (IN)
SET ICOORD=0 FOR MEAN EQUATOR AND EQUINOX OF DATE
SET ICOORD=1 FOR TRUE EQUATOR AND EQUINOX OF DATE
(ECLIPTIC IS ALWAYS THE MEAN PLANE)
RA = RIGHT ASCENSION IN HOURS, REFERRED TO SPECIFIED
EQUATOR AND EQUINOX OF DATE (IN)
DEC = DECLINATION IN DEGREES, REFERRED TO SPECIFIED
EQUATOR AND EQUINOX OF DATE (IN)
ELON = ECLIPTIC LONGITUDE IN DEGREES, REFERRED TO SPECIFIED
ECLIPTIC AND EQUINOX OF DATE (OUT)
ELAT = ECLIPTIC LATITUDE IN DEGREES, REFERRED TO SPECIFIED
ECLIPTIC AND EQUINOX OF DATE (OUT)
NOTE: TO CONVERT ICRS RA AND DEC TO ECLIPTIC COORDINATES (MEAN ECLIPTIC AND EQUINOX OF J2000.0), SET TJD = 0.D0 AND ICOORD = 0. EXCEPT FOR THE INPUT TO THIS CASE, ALL COORDINATES ARE DYNAMICAL.
| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| real(kind=wp) | :: | tjd | ||||
| integer | :: | icoord | ||||
| real(kind=wp) | :: | ra | ||||
| real(kind=wp) | :: | dec | ||||
| real(kind=wp) | :: | elon | ||||
| real(kind=wp) | :: | elat |