Predicts the radial velocity of the observed object as it would be measured by spectroscopic means.

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

Syntax

C#
public void RadVel(
	Object3 CelObject,
	double[] Pos,
	double[] Vel,
	double[] VelObs,
	double DObsGeo,
	double DObsSun,
	double DObjSun,
	ref double Rv
)
Visual Basic
Public Sub RadVel ( _
	CelObject As Object3, _
	Pos As Double(), _
	Vel As Double(), _
	VelObs As Double(), _
	DObsGeo As Double, _
	DObsSun As Double, _
	DObjSun As Double, _
	ByRef Rv As Double _
)
Visual C++
public:
virtual void RadVel(
	Object3 CelObject, 
	array<double>^ Pos, 
	array<double>^ Vel, 
	array<double>^ VelObs, 
	double DObsGeo, 
	double DObsSun, 
	double DObjSun, 
	double% Rv
) sealed

Parameters

CelObject
Type: ASCOM.Astrometry..::..Object3
Specifies the celestial object of interest
Pos
Type: array<System..::..Double>[]()[][]
Geometric position vector of object with respect to observer, corrected for light-time, in AU.
Vel
Type: array<System..::..Double>[]()[][]
Velocity vector of object with respect to solar system barycenter, in AU/day.
VelObs
Type: array<System..::..Double>[]()[][]
Velocity vector of observer with respect to solar system barycenter, in AU/day.
DObsGeo
Type: System..::..Double
Distance from observer to geocenter, in AU.
DObsSun
Type: System..::..Double
Distance from observer to Sun, in AU.
DObjSun
Type: System..::..Double
Distance from object to Sun, in AU.
Rv
Type: System..::..Double%
The observed radial velocity measure times the speed of light, in kilometers/second.

Remarks

Radial velocity is here defined as the radial velocity measure (z) times the speed of light. For a solar system body, it applies to a fictitious emitter at the center of the observed object, assumed massless (no gravitational red shift), and does not in general apply to reflected light. For stars, it includes all effects, such as gravitational red shift, contained in the catalog barycentric radial velocity measure, a scalar derived from spectroscopy. Nearby stars with a known kinematic velocity vector (obtained independently of spectroscopy) can be treated like solar system objects.

See Also