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Stars

WCS Coordinates

This lesson assumes an understanding of celestial positions described as RA/DEC.World Coordinate System (WCS) is the position of an image on the sky sphere. It is the RA and Dec imbedded in a FITS image. When a CCD image is taken, it contains the RA and Dec in the FITS header, but these coordinates are not embeddedin the image. Inserting WCS into the CCD image, specifies the Right Ascension and Declination on the sky associated with a giventhe pixel location in a CCD image.

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