NASA astronauts, from left, Victor Glover and Mike Hopkins, assigned to fly on the first operational mission of SpaceX's Crew Dragon, are in front of the spacecraft at NASA's Johnson Space Center in Houston on Aug. 2, 2018, ahead of the agency's announcement of their commercial crew assignment Aug. 3. Nine U.S. astronauts were selected for commercial crew flight assignments on the first test flights and operational missions for SpaceX's Crew Dragon and Boeing's CST-100 Starliner.