English: Stephen Koerner, Director of the Flight Operations Directorate at NASA’s Johnson Space Center is seen in firing room four during a dress rehearsal in preparation for the launch of a SpaceX Falcon 9 rocket carrying the company's Crew Dragon spacecraft on NASA’s SpaceX Demo-2 mission with NASA astronauts Robert Behnken and Douglas Hurley onboard, Saturday, May 23, 2020, in the Launch Control Center at NASA’s Kennedy Space Center in Florida. NASA’s SpaceX Demo-2 mission is the first launch with astronauts of the SpaceX Crew Dragon spacecraft and Falcon 9 rocket to the International Space Station as part of the agency’s Commercial Crew Program. The test flight serves as an end-to-end demonstration of SpaceX’s crew transportation system. Behnken and Hurley are scheduled to launch at 4:33 p.m. EDT on Wednesday, May 27, from Launch Complex 39A at the Kennedy Space Center. A new era of human spaceflight is set to begin as American astronauts once againlaunch on an American rocket from American soil to low-Earth orbit for the first time since the conclusion of the Space Shuttle Program in 2011. Photo Credit: (NASA/Joel Kowsky)