xy2sky (pronounced X-Y-to-sky) is a utility for getting the world
coordinates of a set of image coordinates in a FITS or IRAF image.
World coordinate system (WCS) information in the image header describes,
in a standard way, the relationship between sky coordinates and image pixels.
This information is used by the program to transform image coordinate (X,Y)
pairs to right ascension and declination sky coordinate pairs. By default,
output coordinates are at the same equinox as is given in the image header,
they may be transformed to B1950/FK4, J2000/FK5, galactic, or ecliptic
coordinates. Input and output files
in the Starbase format will eventually be allowed.
Sky Coordinates from Image Coordinates
The inverse program, sky2xy,
computes image pixel coordinates from world coordinates.
Last updated 10 November 2009 by