Dawn is the first spacecraft planned to orbit two bodies in the solar system. It launched on September 27, 2007 at 11:34 UT. After a gravity assist flyby of Mars (closest approach February 18, 2009 at 00:27:58 UT), it acquired its first approach image of Vesta on May 4, 2011 at 13:35:16. It entered orbit on August 14, 2011.
The mission is divided into phases, listed below. Links from mission phase names take you to pages containing thumbnail versions of all the images released to date. On November 14, 2012, the mission released data to the Planetary Data System covering the Approach, Survey, and HAMO phases; only Approach and Survey indexes are available here so far. Description links take you to relevant Dawn Journals.