9123074 York The Digital Sky Survey is designed to produce a detailed digital photometric map of half the northern sky to about 23rd magnitude. This map will be used to select about a million galaxies and 100,000 quasars for which high-resolution spectra will be obtained with the same wide-field special purpose telescope. The imaging survey will also be used to produce a catalog in four colors of all the detected objects, about 108 galaxies and a similar number of stars, and a million quasar candidates. The survey telescope will take about four years to build and test; the survey would then be completed over a five-year period. This award supports the final design of the telescopes. ***