In the Space Assembly and Encapsulation Facility 2 (SAEF-2), workers at right prepare the upper stage of a Boeing Delta II rocket for mating with the Comet Nucleus Tour (CONTOUR) spacecraft at left. CONTOUR will provide the first detailed look into the heart of a comet -- the nucleus. Flying as close as 60 miles (100 kilometers) to at least two comets, the spacecraft will take the sharpest pictures yet of a nucleus while analyzing the gas and dust that surround these rocky, icy building blocks of the solar system. Launch of CONTOUR aboard the Delta II is scheduled for July 1, 2002, from Launch Complex 17-A, Cape Canaveral Air Force Station