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NOVAS31SiderealTime Method
Computes the Greenwich sidereal time, either mean or apparent, at Julian date 'JdHigh' + 'JdLow'.

Namespace: ASCOM.Astrometry.NOVAS
Assembly: ASCOM.Astrometry (in ASCOM.Astrometry.dll) Version: 6.0.0.0 (6.3.0.2839)
Syntax
public short SiderealTime(
	double JdHigh,
	double JdLow,
	double DeltaT,
	GstType GstType,
	Method Method,
	Accuracy Accuracy,
	ref double Gst
)

Parameters

JdHigh
Type: SystemDouble
High-order part of UT1 Julian date.
JdLow
Type: SystemDouble
Low-order part of UT1 Julian date.
DeltaT
Type: SystemDouble
Difference TT-UT1 at 'JdHigh'+'JdLow', in seconds of time.
GstType
Type: ASCOM.AstrometryGstType
0 ... compute Greenwich mean sidereal time; 1 ... compute Greenwich apparent sidereal time
Method
Type: ASCOM.AstrometryMethod
Selection for method: 0 ... CIO-based method; 1 ... equinox-based method
Accuracy
Type: ASCOM.AstrometryAccuracy
Selection for accuracy
Gst
Type: SystemDouble
Greenwich apparent sidereal time, in hours.

Return Value

Type: Int16
          0 ... everything OK
          1 ... invalid value of 'Accuracy'
          2 ... invalid value of 'Method'
 > 10, < 30 ... 10 + error from function 'CioRai'
 
Remarks
The Julian date may be split at any point, but for highest precision, set 'JdHigh' to be the integral part of the Julian date, and set 'JdLow' to be the fractional part.
See Also