Plotting the 2MASS Point Source Catalog on a Telescope Image
Using SAOimage and imtmc

IMAGE This SAOimage display shows the alignment of 2MASS Point Sources with a test image after a world coordinate system has been fit. The coordinates plotted are based on header keywords describing a plane-tangent system fit by matching HST Guide stars and sources found in the image. This image was produced by a one-line Unix shell script for this task, saotmc:
saoimage -reg `imtmc -r 15 $1` -wcscom stmc_-ha_%s $1
where the argument to the task is the name of the file to be displayed.

The immatch program can provide a list of the stars in the image which match catalog stars.

Click on the image for full-screen view

imtmc finds all of the 2MASS Point Sources in the image based on the world coordinate system parameters in its header and writes them to the region file testx90mw.fits.tmc, seen on the right.

The name of this file is sent to standard output which the backquotes give to SAOimage as a command line argument following the -reg command.

# 2MASS Point Sources (10" radius)
CIRCLE(737,763,16) # tmc 1214.091454
CIRCLE(661,661,16) # tmc 1214.091456
CIRCLE(960,978,16) # tmc 1215.091484
CIRCLE(283,620,16) # tmc 1214.091471
CIRCLE(209,859,16) # tmc 1214.091473
 . . .

CIRCLE(838,1016,16) # tmc 1215.091488
CIRCLE(652,459,16) # tmc 1214.091457
CIRCLE(207,868,16) # tmc 1214.091474
CIRCLE(137,562,16) # tmc 1214.091477
CIRCLE(267,260,16) # tmc 1213.091257
If the w key is struck when the SAOimage cursor is centered on the galaxy in the middle of this picture, stmc is called with the WCS coordinates of the cursor, and the following appears on the user's terminal:

stmc 3.4.0, 11 June 2003, Doug Mink SAO  Find closest star
  2MASS PSC 16:15:56.023 +31:24:24.00 J2000 r= +00:02:00.0 at epoch 2000.00
2MASS_num.   RA2000       Dec2000      MagJ    MagH    MagK    Arcsec
1214.091462 16:15:56.093 +31:24:24.39 15.231  14.833  14.549     0.98

Last updated 18 June 2003 by Doug Mink

[Telescope Data Center] Ex. 1: List the 10 brightest 2MASS Point Source Catalog stars in a FITS image
Ex. 2: List the 2MASS Point Source Catalog stars in a FITS image to a file
[WCSTools programs] [imcat] [imtmc] [SAOimage] [stmc]