The Dawn spacecraft was successfully launched atop a Delta II rocket this morning at 7:34 EST from Cape Canaveral Air Force Station in Florida. Dawn's mission is to study both the dwarf planet Ceres and the planetoid Vesta, two of the largest objects in the asteroid belt. Scientists believe these objects could hold the key to understanding the conditions that were present early in the Solar System's history. Powered by an efficient ion engine, Dawn will rendezvous with Vesta in August 2011, leaving in May 2012, then rendezvousing with Ceres in February 2015, with its mission ending in July 2015.