This function rotates a vector from the terrestrial to the celestial system.

Namespace: ASCOM.Astrometry.NOVAS
Assembly: ASCOM.Astrometry (in ASCOM.Astrometry.dll) Version: 6.0.0.0 (6.1.1.2619)

Syntax

C#
public short Ter2Cel(
	double JdHigh,
	double JdLow,
	double DeltaT,
	Method Method,
	Accuracy Accuracy,
	OutputVectorOption OutputOption,
	double x,
	double y,
	double[] VecT,
	ref double[] VecC
)
Visual Basic
Public Function Ter2Cel ( _
	JdHigh As Double, _
	JdLow As Double, _
	DeltaT As Double, _
	Method As Method, _
	Accuracy As Accuracy, _
	OutputOption As OutputVectorOption, _
	x As Double, _
	y As Double, _
	VecT As Double(), _
	ByRef VecC As Double() _
) As Short
Visual C++
public:
virtual short Ter2Cel(
	double JdHigh, 
	double JdLow, 
	double DeltaT, 
	Method Method, 
	Accuracy Accuracy, 
	OutputVectorOption OutputOption, 
	double x, 
	double y, 
	array<double>^ VecT, 
	array<double>^% VecC
) sealed

Parameters

JdHigh
Type: System..::..Double
High-order part of UT1 Julian date.
JdLow
Type: System..::..Double
Low-order part of UT1 Julian date.
DeltaT
Type: System..::..Double
Value of Delta T (= TT - UT1) at the input UT1 Julian date.
Method
Type: ASCOM.Astrometry..::..Method
Selection for method: 0 ... CIO-based method; 1 ... equinox-based method
Accuracy
Type: ASCOM.Astrometry..::..Accuracy
Selection for accuracy
OutputOption
Type: ASCOM.Astrometry..::..OutputVectorOption
0 ... The output vector is referred to GCRS axes; 1 ... The output vector is produced with respect to the equator and equinox of date.
x
Type: System..::..Double
Conventionally-defined X coordinate of celestial intermediate pole with respect to ITRF pole, in arcseconds.
y
Type: System..::..Double
Conventionally-defined Y coordinate of celestial intermediate pole with respect to ITRF pole, in arcseconds.
VecT
Type: array<System..::..Double>[]()[][]
Position vector, geocentric equatorial rectangular coordinates, referred to ITRF axes (terrestrial system) in the normal case where 'option' = 0.
VecC
Type: array<System..::..Double>[]()[][]%
Position vector, geocentric equatorial rectangular coordinates, referred to GCRS axes (celestial system) or with respect to the equator and equinox of date, depending on 'Option'.

Return Value

    0 ... everything is ok
    1 ... invalid value of 'Accuracy'
    2 ... invalid value of 'Method'
 > 10 ... 10 + error from function 'CioLocation'
 > 20 ... 20 + error from function 'CioBasis'
 

Remarks

'x' = 'y' = 0 means no polar motion transformation.

The 'option' flag only works for the equinox-based method.

See Also