On Launch Pad 17-B at Cape Canaveral Air Force Station, workers prepare the solid rocket booster to be raised off the transporter. The SRB is one of nine to be mated to the Delta II rocket that will launch the Dawn spacecraft. 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/Jim Grossmann