An aerial view of NASA's mobile launcher (ML) atop crawler-transporter 2 as it moves along the crawlerway, making the turn to Launch Pad 39B on Aug. 31, 2018, at the agency's Kennedy Space Center in Florida. In view on top of the ML is the American flag. The ML will undergo a fit check on the surface of the pad, followed by several days of systems testing. The 380-foot-tall mobile launcher is equipped with the crew access arm and several umbilicals that will provide power, environmental control, pneumatics, communication and electrical connections to NASA's Space Launch System (SLS) and Orion spacecraft. Exploration Ground Systems is preparing the ground systems necessary to launch SLS and Orion on Exploration Mission-1, missions to the Moon and on to Mars.