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This compact version of the Guide Star Catalogue Version 1.1
(an all-sky astrometric and photometric catalog to support the operation 
of the Hubble Space Telescope, The Association of Universities for Research in
Astronomy, Inc. ([c] 1989, 1992)) was prepared by 
    A. Preite-Martinez and F. Ochsenbein, and presented as 
    "A Pocket version of the Guide Star Catalogue" in
    "Handling & Archiving Data from Ground-based Telescopes", Trieste 1993,
     ESO Conference and Workshop Proceedings No 50 (ISBN 3-923524-53-6),
     p. 199
(details at http://archive.eso.org/skycat/gsc-engine/node2.html)
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The compressed tables (useable on any architecture with the provided
programs) follow exactly the directory structure of the original GSC.

Source programs (to query the GSC and generate the binary indexes)
are in src subdirectory.

Binary files include executables and binary indexes for fast queries; 
these are stored in bin subdirectory (Solaris version) and bin-dos
(PC MS-DOS version)

The only file required to generate the binary indexes (by means of the 
genreg.exe program) is regions.ord (sorted list of regions)

A complete stand-alone PC version of the GSC catalogue requires all
files from bin-dos , N* and S* subdirectories. (total about 300Mbytes)
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The query program, gsc.exe, allows to retrieve the GSC stars in a
small circle around a target position (or at a distance between two
limits), or from a GSC-id identification (a number combining the region
and star) with the -g option. This program has a lot of other options 
summarized with the -help option.

To have gsc.exe running properly, two environment variables are required:
GSCDAT :    the name of the directory which contains the [NS]* subdirectories;
GSCBIN :    the name of the directory which contains the binary indexes.
The default setup of these variables are:
GSCDAT=/GSC  on Unix       set GSCDAT=\GSC     on MS-DOS
GSCBIN=$GSCDAT/bin         set GSCBIN=$GSCDAT\bin

The usage of two variables allow to move only the binary files ($GSCBIN) 
to a magnetic drive, leaving the bulk data ($GSCDAT) to a dedicated (e.g. 
optical) drive.

Questions, comments, suggestions are welcome!
Francois Ochsenbein, 1996 April 25
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A program running in client/server mode allows to access this version
of the GSC, as well as most other catalogues stored at CDS, from any
Internet node: see   ftp://cdsarc.u-strasbg.fr/pub/cats/cdsclient.tar.Z
A WWW interface to query this version of the GSC is also available at URL
      http://cdsweb.u-strasbg.fr/cgi-bin/GSC1.1
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        _/_/_/_/_/_/ . . .             Centre de Donnees astronomiques de
      _/                               Strasbourg
     _/                                http://cdsweb.u-strasbg.fr/CDS.html
    _/        _/_/  _/_/_/
   _/      _/      _/    _/            Francois Ochsenbein
    _/_/_/_/      _/    _/_/_/_/       Internet: francois@astro.u-strasbg.fr
         _/      _/    _/      _/         Phone: +33 88 15 07 55
          _/_/  _/_/_/        _/            Fax: +33 88 37 14 08
                             _/            Post: Observatoire Astronomique
                            _/                   11, rue de l'Universite
        . . . _/_/_/_/_/_/_/                     67000 STRASBOURG, France
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