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NOVAS3TransformHip Method
Convert Hipparcos catalog data at epoch J1991.25 to epoch J2000.0, for use within NOVAS.

Namespace: ASCOM.Astrometry.NOVAS
Assembly: ASCOM.Astrometry (in ASCOM.Astrometry.dll) Version: 6.0.0.0 (6.2.0.2774)
Syntax
public void TransformHip(
	CatEntry3 Hipparcos,
	ref CatEntry3 Hip2000
)

Parameters

Hipparcos
Type: ASCOM.AstrometryCatEntry3
An entry from the Hipparcos catalog, at epoch J1991.25, with all members having Hipparcos catalog units. See Note 1 below
Hip2000
Type: ASCOM.AstrometryCatEntry3
The transformed input entry, at epoch J2000.0. See Note 2 below
Remarks
To be used only for Hipparcos or Tycho stars with linear space motion. Both input and output data is in the ICRS.

1. Input (Hipparcos catalog) epoch and units:

  • Epoch: J1991.25
  • Right ascension (RA): degrees
  • Declination (Dec): degrees
  • Proper motion in RA: milliarcseconds per year
  • Proper motion in Dec: milliarcseconds per year
  • Parallax: milliarcseconds
  • Radial velocity: kilometers per second (not in catalog)

2. Output (modified Hipparcos) epoch and units:

  • Epoch: J2000.0
  • Right ascension: hours
  • Declination: degrees
  • Proper motion in RA: milliarcseconds per year
  • Proper motion in Dec: milliarcseconds per year
  • Parallax: milliarcseconds
  • Radial velocity: kilometers per second
>

See Also