The HST GSC Catalog over the World Wide Web

All WCSTools programs which search catalogs can access the HST GSC and USNO-A2.0 catalogs over the web from the ESO servers. Code to assemble and send http queries to those servers is built into the web access subroutine. Since tab-separated Starbase tables, a native WCSTools catalog format, are an output option from the catalog server, they are parsed and sorted just like local Starbase files.

The following example searches a 6 arcminute radius circle around 10:00 30:00 J2000 and returns all of the stars found there, sorted by their distance from the search center. The verbose mode (-v) echoes the http query sent. 


$ setenv GSC_PATH "http://archive.eso.org/skycat/servers/gsc-server"
$ sgsc -s p -vhr 360 10:00 30:00 J2000

sgsc 3.0.6, 6 November 2001, Doug Mink SAO
Center:  10:00:00.000   +30:00:00.00 J2000
Area:    00:00:55.43 x +00:12:00.00
HST GSC   10:00:00.000 +30:00:00.00 J2000 r= 360.00 at epoch 2000.00
http://archive.eso.org/skycat/servers/gsc-server?10.0000000+30.0000000&r=0,6.000&nout=100000&f=8
SearchLim: RA: 09:59:32.287 - 10:00:27.713  Dec: +29:54:00.00 - +30:06:00.00
TABREAD: Catalog http://archive.eso.org/skycat/servers/gsc-server : 6 / 7 / 6 found
6 HST Guide Stars
GSC number  RA2000       Dec2000      Mag  Class Band N  Arcsec
2503.1463 10:00:07.764 +30:00:05.04  12.55    0    0  0  100.98
2502.0993 09:59:54.401 +30:03:52.09  14.74    0    0  0  243.22
1967.0343 09:59:37.111 +29:58:13.76  14.74    0    0  0  315.78
1967.0307 10:00:09.794 +29:54:57.31  12.01    0    0  0  328.36
2502.0994 09:59:39.454 +30:03:41.58  13.47    0    0  0  346.83
2503.1441 10:00:17.563 +30:04:30.47  13.26    0    0  0  353.79
Running the same search with a vvv flag prints the actual returned information, (the returned lines are split here to fit on the page): 
$ sgsc -vvvhr 360 10:00 30:00 J2000

sgsc 3.0.6, 6 November 2001, Doug Mink SAO
HST GSC   10:00:00.000 +30:00:00.00 J2000 r= 360.00 at epoch 2000.00
Center: 1000+3000

gsc_id          ra      dec             pos-e   mag     mag-e   mu         d'   pa
------------    -------------   --------        -----   ---     -----   --      ----- --
GSC0196700307   150.04081        29.91592        0.2    12.01   0.34    F          5.47157;
GSC0250301463   150.03235        30.00140        0.2    12.55   0.35    F          1.68 87;
GSC0250301441   150.07318        30.07513        0.2    13.26   0.35    F          5.90 40;
GSC0250200994   149.91439        30.06155        0.2    13.47   0.36    F          5.78310;
GSC0196700343   149.90463        29.97049        0.2    14.74   0.36    F          5.26250;
GSC0250200993   149.97667        30.06447        0.2    14.74   0.35    F          4.05343;
[EOD]

ADASS 2001 WCSTools 3.0 paper