The U.S. Air Force’s X-37B space plane has winged past 200 days in orbit on its latest clandestine mission. That mission, known as Orbital Test Vehicle-5 (OTV-5), began Sept. 7, 2017, when the robotic spacecraft launched atop a SpaceX Falcon 9 booster from NASA’s Kennedy Space Center (KSC) in Florida. According to Air Force officials, […]