At Cape Canaveral Air Force Station, a United Launch Alliance Centaur offsite vertical integration stack arrives at Space Launch Complex 41 for mounting atop an Atlas V first stage. The stack includes the Centaur mated to the interstage adapter for mating to the Atlas V and the boat tail which will attach to the payload. Together, the rocket will boost a Cygnus spacecraft on the Orbital ATK Commercial Resupply Services-6 mission to deliver hardware and supplies to the International Space Station.