James J. Condon


The 1.4 GHz NRAO VLA Sky Survey (NVSS) covers the sky north of -40 deg declination (82% of the celestial sphere). The principal data products are:

The NVSS was made as a service to the astronomical community, and the principal data products are being released as soon as they have been produced and verified. For more information, see the NVSS Home Page or the paper: Condon, J. J., Cotton, W. D., Greisen, E. W., Yin, Q. F., Perley, R. A., Taylor, G. B. & Broderick, J. J. 1998, AJ, 115, 1693.


The Green Bank 4.85 GHz sky survey was made with the (former) 91 m telescope during November 1986 and October 1987. The final set of images covering the declination band from 0 to +75 deg was constructed with data from both epochs. Its noise and position errors are nearly a factor of sqrt(2) smaller than in the epoch 1987 images, from which the 87GB catalog of 54,579 sources stronger than S ~ 25 mJy was extracted. The new images were used to make the GB6 catalog of 75,162 discrete sources with angular sizes < 10.5 arcmin and flux densities above S ~ 18 mJy at 6 cm wavelength. The GB6 catalog is available in machine-readable versions with either B1950 or J2000 positions and as a printed book with peak flux densities and B1950 positions only.


J. J. Condon
National Radio Astronomy Observatory
520 Edgemont Road
Charlottesville, VA 22903-2475 USA
+1-804-296-0322 (Tel)
+1-804-296-0278 (Fax)

jcondon@nrao.edu