Download CURSA [1ex] Catalogue and Table Manipulation
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SUN/190.11 —Importing regions of the HST GSC catcdsin equinox=J2000 82 epoch=J1995.3 Obviously, you substitute values appropriate to your catalogue. The equinox and epoch should have their usual CURSA syntax (see Section 7). Either, neither or both can be specified. If you wish to suppress the automatic interpretation of celestial coordinates, and instead have the sexagesimal subdivisions of angles treated as separate columns, type: catcdsin angles=no The input CDS description file does not have to be called ReadMe. For example, a file called cdsdesc.lis could be processed by typing: catcdsin infile=cdsdesc.lis These various options can be combined. For example, to process a file called cdsdesc.lis, specifying the equinox as J2000 and not copying the CDS file as textual information type: catcdsin infile=cdsdesc.lis equinox=J2000 text=none CDS ReadMe files can (and often do) contain descriptions of more than one catalogue or table. Usually these catalogues or tables will be closely related; perhaps a main catalogue and a table of notes. catcdsin creates a separate STL description file for every catalogue found in the ReadMe file. A few CDS catalogues do not contain celestial coordinates; spectral line wavelength lists are the obvious example. Occasionally the coordinates may be in a non-standard format which catcdsin does not interpret properly. In this case it may be possible to fix-up the STL description file generated by catcdsin by hand. See Appendices D and E for details of the STL format. Such occurrences seem to be rare. 24 Importing regions of the HST GSC The Hubble Space Telescope Guide Star Catalog (GSC, see Section 2, above) is divided into some 9537 regions and each region is held as a separate FITS table file. These FITS tables can be read directly by CURSA. However, there is a CURSA utility to convert them to a more convenient format. I recommend that you use it to convert a region before accessing the region with other CURSA applications. The utility generates a new version of the region with the following changes: • the units of the Right Ascension and Declination are changed from degrees to radians and the UNITS attributes set so that CURSA can format the coordinates as sexagesimal values for display, • the region is sorted into ascending Declination order so that (fast) range selections can be performed on it.