Sloan Digital Sky Survey

"The Sloan Digital Sky Survey (SDSS) is one of the most ambitious and influential surveys in the history of astronomy .... SDSS data have been released to the scientific community and the general public in annual increments, with the final public data release from SDSS-II occurring in October 2008 .... Meanwhile, SDSS is continuing with the Third Sloan Digital Sky Survey (SDSS-III)..... SDSS-III will continue operating and releasing data through 2014"

http://www.sdss.org/