Jim Bolton, Core Stage Element Operations manager in Exploration Ground Systems (EGS), is at the north end of the transfer aisle in the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida on Oct. 3, 2019. Behind him is the Space Launch System Core Stage pathfinder. A cover, called a spider, is being attached to the top of the pathfinder. With the spider secured in place, a crane will be attached to it to lift the pathfinder into the vertical position. The 212-foot-long core stage pathfinder arrived aboard NASA's Pegasus Barge at Kennedy’s Launch Complex 39 turn basin wharf on Sept. 27, 2019. The Pegasus Barge made its first delivery to Kennedy in support of the agency's Artemis missions. The upgraded 310-foot-long barge arrived, ferrying the SLS core stage pathfinder, a full-scale mock-up of the rocket's core stage. It will be used by EGS and its contractor, Jacobs, to practice offloading, moving and stacking maneuvers, using important ground support equipment to train employees and certify all the equipment works properly. The pathfinder will stay at Kennedy for approximately one month before trekking back to NASA's Michoud Assembly Facility in Louisiana.