The Palomar Digital Sky Survey (DPOSS)
  We describe DPOSS, a new digital survey of the northern sky, based on the POSS-II photographic sky atlas. The survey covers the entire sky north of delta = -3 deg in 3 bands, calibrated to the Gunn $gri$ system, reaching to equivalent limiting magnitude of B_lim ~ 22 mag. As a result of the state-of-the-art digitisation of the plates, detailed processing of the scans, and a very extensive CCD calibration program, the data quality exceedes that of the previous photographically-based efforts. The end product of the survey will be the Palomar-Norris Sky Catalog, anticipated to contain > 50 million galaxies and > 2 billion stars, down to the survey classification limit, ~ 1 mag above the flux detection limit. Numerous scientific projects utilising these data have been started, and we describe briefly some of them; they illustrate the scientific potential of the data, and serve as the scientific verification tests of the survey. Finally, we discuss some general issues posed by the advent of multi-terabyte data sets in astronomy. 
S. G. Djorgovski (1), R. R. Gal (1), S. C. Odewahn (1), R. R. de   Carvalho (2), R. Brunner (1), G. Longo (3), R. Scaramella...