The NRAO VLA Sky Survey

The NRAO VLA Sky Survey (NVSS) covers the sky north of J2000.0 = -40 (82 percent of the celestial sphere) at 1.4 GHz. The principal data products are (1) a set of 2326 4 deg x 4 deg continuum 'cubes' with three planes containing Stokes I, Q, and U images plus (2) a catalog of almost 2 x 10 exp 6 discrete sources stronger than S roughly 2.5 mJy. The images all have Theta = 45 arcsec FWHM resolution and nearly uniform sensitivity. Their rms brightness fluctuations are sigma roughly 0.45 mJy/beam roughly 14 K (Stokes I) and sigma roughly 0.29 mJy/beam roughly 0.09 K (Stokes Q and U). The rms uncertainties in right ascension and declination vary from less than about 1 arcsec for the N roughly 4 x 10 exp 5 sources stronger than 15 mJy to 7 arcsec at the survey limit. (Author)