The usual format of a catalogue is as above, i.e. an object identifier followed by an RA and DEC (in J2000 decimal degrees). Note the <TAB> strings shouldn't be typed in, they are shown explicitly just to make clear where they should be placed. The TST format is also recognised by the TOPCAT and CURSA packages (SUN/190). CURSA also contains a description of this format.# comment keyword1: value1 keyword2: value2 ... ID <TAB> RA <TAB> DEC <TAB> MAG ... -- -- --- --- OBJ1 <TAB> 210.00 <TAB> 54.00 <TAB> 16.1 OBJ2 <TAB> 210.01 <TAB> 54.01 <TAB> 15.1 ....
Additional formats that can be also read and written by GAIA (with a performance penalty) are those supported by the CURSA package (i.e. FITS-tables and STL format) and the ``ASCII_HEAD'' format of the SExtractor/EXTRACTOR package (SUN/226), as well as the XML VOTable format.
The format that is used to open or write a catalogue, is determined by the file extension:
GAIA -- Graphical Astronomy and Image Analysis Tool