ASCOM Library
Position
NOVAS-COM: PositionVector Class
Definition
Namespace: ASCOM.Tools.NovasCom
Assembly: ASCOM.AstrometryTools (in ASCOM.AstrometryTools.dll) Version: 2.2.1+77356f79b05b579f6d860a4edd5934fda9fe29e4
Assembly: ASCOM.AstrometryTools (in ASCOM.AstrometryTools.dll) Version: 2.2.1+77356f79b05b579f6d860a4edd5934fda9fe29e4
C#
public class PositionVectorVB
Public Class PositionVector- Inheritance
- Object PositionVector
Remarks
NOVAS-COM objects of class PositionVector contain vectors used for positions (earth, sites,
stars and planets) throughout NOVAS-COM. Of course, its properties include the x, y, and z
components of the position. Additional properties are right ascension and declination, distance,
and light time (applicable to star positions), and Alt/Az (available only in PositionVectors
returned by Star or Planet methods GetTopocentricPosition()). You can initialize a PositionVector
from a Star object (essentially an FK5 or HIP catalog entry) or a Site (lat/long/height).
PositionVector has methods that can adjust the coordinates for precession, Novas.Aberration and
proper motion. Thus, a PositionVector object gives access to some of the lower-level NOVAS functions.
Note: The equatorial coordinate properties of this object are dependent variables, and thus are read-only. Changing any Cartesian coordinate will cause the equatorial coordinates to be recalculated.
Constructors
| PositionVector | Create a new, uninitialised position vector |
| PositionVector(Double, Double, Double, Double, Double, Double, Double) | Create a new position vector with supplied initial values |
| PositionVector(Double, Double, Double, Double, Double, Double, Double, Double, Double) | Create a new position vector with supplied initial values |
Properties
| Azimuth | The azimuth coordinate (degrees, + east) |
| Declination | Declination coordinate |
| Distance | Distance/Radius coordinate |
| Elevation | The elevation (altitude) coordinate (degrees, + up) |
| LightTime | Light time from Body to origin, days. |
| RightAscension | RightAscension coordinate, hours |
| x | Position Cartesian x component |
| y | Position Cartesian y component |
| z | Position Cartesian z component |
Methods
| Aberration | Adjust the position vector of an object for Novas.Aberration of light |
| Precess | Adjust the position vector for precession of equinoxes between two given epochs |
| ProperMotion | Adjust the position vector for proper motion (including foreshortening effects) |
| SetFromSite | Initialize the PositionVector from a Site object and Greenwich apparent sidereal time. |
| SetFromSiteJD(Site, Double) | Initialize the PositionVector from a Site object using UTC Julian date |
| SetFromSiteJD(Site, Double, Double) | Initialize the PositionVector from a Site object using UTC Julian date and Delta-T |
| SetFromStar | Initialize the PositionVector from a Star object. |