Downloading and installing the GSCX

You need the Guide Star Catalogue, or GSC, so that COELIX APEX can display the stars down to magnitude 15.6 in the visual fields and in the sky maps at a 16 X zoom.

In this page, we provide a free 180 MB version of the GSC compatible with COELIX APEX. This GSCX version is a modified version of the GSC-ACT in which all the stars brighter than magnitude 10.5 have been removed (the brighter stars are already in other catalogues) and in which multiple entries of a same star (up to 4 in some cases) have been combined into one single. This reduces the size to 180 MB (rather than 290 MB for the original).

The Guide Star Catalogue beeing in the public domain, you can download it for free from the Web. Since the original GSC is quite large (290 MB), it is strongly recommended to have a fast connection.

Credits :
The Guide Star Catalog Version 1.1-ACT (GSC-ACT Catalogue compact version), 
Lasker B.M., Russel J.N., Jenkner H., Preite-Martinez  A., Ochsenbein F.
The Association of Universities for Research in Astronomy, Inc.  (© 1989, 1992, 1996)
Put online : Centre de Données astronomiques de Strasbourg (CDS).

By following the steps described below, in addition to have the GSC installed in COELIX, you will have a copy of the installation programs that we recommend to save also on a CD.
Saving the installation files
Download and save each file gsc_north_setup.exe and gsc_south_setup.exe on your computer. The dialog box that opens by clicking a button asks if you want to run or save the file. Choose "Save" :

Running the installation programs
Start successively each of the two installers gsc_north_setup.exe and gsc_south_setup.exe by double-clicking on their names and follow the instructions in each program. Choose to do the installation in the folder of Coelix Apex, normally in C:\NGC7000\CoelixApex.

If you look at the content of the COELIX folder after the installations, you will find the .GSC files in the regions subfolders "N0000" to "S8230", that are themselves in the "gscx" subfolder.

Verifying the installation
Start the COELIX software and choose option "The default GSCX folder in Coelix" in the dialog box that opens from the menu Preferences and Settings/Path of the Guide Star Catalogue :

In the COELIX software, display a sky map with a 16X zoom, or a visual field with a magnification high enough to verify that you can see stars to magnitude 15.