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NOVAS2TransformHip Method
To convert Hipparcos data at epoch J1991.25 to epoch J2000.0 and FK5-style units.

Namespace: ASCOM.Astrometry.NOVAS
Assembly: ASCOM.Astrometry (in ASCOM.Astrometry.dll) Version: 6.0.0.0 (6.2.0.2774)
Syntax
public static void TransformHip(
	ref CatEntry hipparcos,
	ref CatEntry fk5
)

Parameters

hipparcos
Type: ASCOM.AstrometryCatEntry
An entry from the Hipparcos catalog, at epoch J1991.25, with all members having Hipparcos catalog units. See Note 1 below
fk5
Type: ASCOM.AstrometryCatEntry
The transformed input entry, at epoch J2000.0, with all members having FK5 catalog units. See Note 2 below
Remarks
To be used only for Hipparcos or Tycho stars with linear space motion.

 1. Hipparcos epoch and units:
    Epoch: J1991.25
    Right ascension (RA): degrees
    Declination (Dec): degrees
    Proper motion in RA * cos (Dec): milliarcseconds per year
    Proper motion in Dec: milliarcseconds per year
    Parallax: milliarcseconds
    Radial velocity: kilometers per second (not in catalog)
 
 2. FK5 epoch and units:
    Epoch: J2000.0
    Right ascension: hours
    Declination: degrees
    Proper motion in RA: seconds of time per Julian century
    Proper motion in Dec: arcseconds per Julian century
    Parallax: arcseconds
    Radial velocity: kilometers per second

See Also