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Image and Catalog Archive ACT Format


DESCRIPTION OF THE FIELDS IN THE ACT CATALOGUE:


 

This is a compacted, version of the ACT. Not all fields have been retained from the original. The ASCII version of the extracted subset of the ACT catalogue contains some (or all) of the following fields:

  1. ID - identification number. This number is the star ID as given in the AC2000 catalogue.
  2. RA - the Right Ascension of the object in hours or degrees. The epoch and equinox are those given in the file header. The default is equinox and epoch J2000.0.
  3. DEC - the Declination of the object in degrees. The epoch and equinox are those given in the file header. The default is equinox and epoch J2000.0.
  4. MuRa - the proper motion in RA. This is given in angular velocity units of milli-arcseconds per year. [This equals MuRA = d(RA)/dt x cos(DEC)]
  5. MuDec - the proper motion in DEC. This is given in angular velocity units of milli-arcseconds per year.
  6. B - Tycho blue magnitude (BT). This is the B magnitude from the Tycho Catalogue.
  7. V - Tycho Visual magnitude (VT). This is the V magnitude from the Tycho Catalogue.
  8. Xi (computed quantity) - the standard coordinate Xi, in the tangent plane projection about the requested region center. This is only computed for rectangular or circular regions. The units are decimal arcseconds.
  9. Eta (computed quantity) - the standard coordinate Eta, in the tangent plane projection about the requested region center. This is only computed for rectangular or circular regions. The units are decimal arcseconds.
  10. DistCtr (computed quantity) - distance from this object to the extraction center in arcseconds.
  11. Gal_L (computed quantity) - computed galactic longitude, in decimal degrees.
  12. Gal_B (computed quantity) - computed galactic latitude, in decimal degrees.

Last updated: 2008Dec12 by sel
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