WCSTools

sgsca
GSC-ACT Star Catalog Search Program

WCSTools programs
sgsca is a utility for finding objects in the GSC-ACT Star Catalog, a reprocessed version of the HST Guide Star Catalog, located in a specified region of the sky and listing their positions. It is a symbolic link to scat, and is equivalent to running scat -c gsca ....

By default, only the brightest 100 objects (or closest 100, if the -s p option is used) are returned. Use the -n option to increase this number.

As of version 2.9.4, the bandpass and number of entries for a star are printed in addition to the object class. Type scat band to get a listing of the band codes and their meanings.

Output is to standard out, unless the -w flag is set, in which case it goes to objectname.gscact or search.gscact. It is somewhat similar to RGSC, which can search from lists of coordinates but cannot sort the output.

Set the environment variable GSCA_NORTH to the directory containing the northern hemisphere CDROM and GSCA_SOUTH to the directory containing the southern hemisphere CDROM. The default directories are set in cdna and cdsa near the start of libwcs/gscread.c. Set GSCA_NORTH to a URL to read the GSC-ACT over the world wide web.

[ Search the USNO-A2.0 Catalog using this software]

Command Line Arguments

CGI Queries and Parameters

As of version 2.9.4, sgsca can be used remotely as a CGI executable.

Examples

Search with results to standard output
Search with results to a file
Find closest star
Find stars by number
Match stars in input catalog

Last updated 30 July 2001 by Doug Mink dmink@cfa.harvard.edu

Telescope Data Center