On Launch Pad 17-B at Cape Canaveral Air Force Station, workers make final checks of the Delta II rocket in the mobile service tower. The rocket is the launch vehicle for the Dawn spacecraft, targeted for liftoff on June 30. Dawn's mission is to explore two of the asteroid belt's most intriguing and dissimilar occupants: asteroid Vesta and the dwarf planet Ceres. Photo credit: NASA/Amanda Diller