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NOVAS3Gcrs2Equ Method
Converts GCRS right ascension and declination to coordinates with respect to the equator of date (mean or true).

Namespace: ASCOM.Astrometry.NOVAS
Assembly: ASCOM.Astrometry (in ASCOM.Astrometry.dll) Version: 6.0.0.0 (6.2.0.2774)
Syntax
public short Gcrs2Equ(
	double JdTt,
	CoordSys CoordSys,
	Accuracy Accuracy,
	double RaG,
	double DecG,
	ref double Ra,
	ref double Dec
)

Parameters

JdTt
Type: SystemDouble
TT Julian date of equator to be used for output coordinates.
CoordSys
Type: ASCOM.AstrometryCoordSys
Coordinate system selection for output coordinates.; 0 ... mean equator and equinox of date; 1 ... true equator and equinox of date; 2 ... true equator and CIO of date
Accuracy
Type: ASCOM.AstrometryAccuracy
Selection for accuracy
RaG
Type: SystemDouble
GCRS right ascension in hours.
DecG
Type: SystemDouble
GCRS declination in degrees.
Ra
Type: SystemDouble
Right ascension in hours, referred to specified equator and right ascension origin of date.
Dec
Type: SystemDouble
Declination in degrees, referred to specified equator of date.

Return Value

Type: Int16
    0 ... everything OK
 >  0 ... error from function 'Vector2RaDec'' 
 > 10 ... 10 + error from function 'CioLocation'
 > 20 ... 20 + error from function 'CioBasis'
 
>
Remarks
For coordinates with respect to the true equator of date, the origin of right ascension can be either the true equinox or the celestial intermediate origin (CIO).

This function only supports the CIO-based method.

See Also