This introductory recipe demonstrates displaying an image, which is the simplest use of GAIA. The
image used is file
ngc1275jkt.sdf, a reduced V band CCD image of the galaxy NGC 1275 obtained
with the Jacobus Kapteyn Telescope (JKT) on La Palma. It was derived from observations included on
the CD-ROM Astronomical Images by Jaffe. However, the same data are publicly available from the
ING (Isaac Newton Group) data archive maintained at the Institute of Astronomy, University of
Cambridge. See URL:
For technical reasons there are some differences in the arrangement of the FITS headers in the archive and CD-ROM versions of the files but both contain identical astronomical information.
ngc1275jkt.sdf was created by reducing the raw observations using CCDPACK (see SUN/139)
following the recipe in SC/5. The data reduction is not considered further here. The image is in the
NDF data format (see Section 4 for details of the data formats available to GAIA). If you prefer you
could use an image of your own rather than this one.
Assuming that you have copied all the example data files for the cookbook into your current directory (as described in Section 7, above) and configured your terminal or workstation to receive X-output, then proceed as follows.
The ampersand (‘
&’) is, of course, simply to run GAIA as a detached process, so that you can
continue to issue Unix commands from the command line. A window displaying a start-up
message should be displayed, shortly followed by the main GAIA window. If these windows do
not appear then GAIA is not properly installed at your site; in the first instance seek assistance
from your site manager.
ngc1275jkt.sdfby clicking the File menu (leftmost of the options in the menu-bar at the top of the window), selecting Open… and using the file-picker which appears to choose the appropriate file.
The display should now look something like Figure 1.
Note that this option will work with images in the NDF format as well as those in the FITS format (because the NDF format can contain FITS-like header information which GAIA can access).
On-line help is available from the Help menu at the extreme right of the menu-bar at the top of the window. If you click on this menu and choose the Help topics index… item then the introductory page of the GAIA on-line help information will appear (see Figure 2). From this page you can follow hyper-links to further pages giving notes on how to perform numerous common tasks with GAIA. You are likely to find this help information very useful.