The Digitized Sky Survey (DSS)

The Digitized Sky Survey is a collection of scanned photographic images from the Palomar Observatory Sky Survey and the Anglo-Australian Observatory (AAO). These digital images were used by the Space Telescope Science Institute to create the Hubble Guide Star Catalog (GSC), a large database of stars and other celestial objects. With this database, the Hubble Space Telescope is able to accurately locate, track and photograph celestial objects.

The first eight RealSky CDs contain images of the entire Northern Hemisphere down to 15 degrees south declination. CDs nine through 18 contain the entire Southern Hemisphere up to three degrees north.