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NOVAS3Equ2Ecl Method
To convert right ascension and declination to ecliptic longitude and latitude.

Namespace: ASCOM.Astrometry.NOVAS
Assembly: ASCOM.Astrometry (in ASCOM.Astrometry.dll) Version: 6.0.0.0 (6.2.0.2774)
Syntax
public short Equ2Ecl(
	double JdTt,
	CoordSys CoordSys,
	Accuracy Accuracy,
	double Ra,
	double Dec,
	ref double ELon,
	ref double ELat
)

Parameters

JdTt
Type: SystemDouble
TT Julian date of equator, equinox, and ecliptic used for coordinates.
CoordSys
Type: ASCOM.AstrometryCoordSys
Coordinate system: 0 ... mean equator and equinox of date 'JdTt'; 1 ... true equator and equinox of date 'JdTt'; 2 ... ICRS
Accuracy
Type: ASCOM.AstrometryAccuracy
Selection for accuracy
Ra
Type: SystemDouble
Right ascension in hours, referred to specified equator and equinox of date.
Dec
Type: SystemDouble
Declination in degrees, referred to specified equator and equinox of date.
ELon
Type: SystemDouble
Ecliptic longitude in degrees, referred to specified ecliptic and equinox of date.
ELat
Type: SystemDouble
Ecliptic latitude in degrees, referred to specified ecliptic and equinox of date.

Return Value

Type: Int16
 0 ... everything OK
 1 ... invalid value of 'CoordSys'
 
Remarks
To convert ICRS RA and dec to ecliptic coordinates (mean ecliptic and equinox of J2000.0), set 'CoordSys' = 2; the value of 'JdTt' can be set to anything, since J2000.0 is assumed. Except for the input to this case, all input coordinates are dynamical.
See Also