There are four flights in all-two each for SpaceX's Crew Dragon and Boeing's CST-100 Starliner vehicle-scheduled to launch to the International Space Station (ISS) throughout 2019 once uncrewed test flights are complete.
SpaceX and Boeing were picked by NASA in 2014 to develop spacecrafts to return that capability to the United States, and both companies are slated to launch their first crewed missions in the next year.
"For the first time since 2011, we are on the brink of launching American astronauts on American rockets from American soil", said NASA Administrator Jim Bridenstine.
Boeing's first test mission will send astronauts Eric Boe, Nicole Aunapu Mann, and Chris Ferguson aloft.
For the past seven years, Nasa astronauts have hitched rides to the orbiting outpost on Russia's Soyuz spacecraft - at a cost of some US$80 million a seat.
"What an exciting and incredible day", Jim Bridenstine, NASA's administrator, said at the announcement at NASA's Johnson Space Center in Houston. "This accomplished group of American astronauts, flying on new spacecraft developed by our commercial partners Boeing and SpaceX, will launch a new era of human spaceflight", Mr. Bridenstine said. "Today's announcement advances our great American vision and strengthens the nation's leadership in space".
Astronaut Doug Hurley, who will be on the first crew of the SpaceX Dragon, hinted at the delays when he noted, "The first flight is something you dream about as a test pilot, and you don't think it's ever going to happen to you".
SpaceX's first crewed test flight on the Crew Dragon will be flown by astronauts Bob Behnken and Doug Hurley in April 2019. He began his career with the Air Force, and served as a fighter pilot, test pilot and colonel.
Each test flight will provide data on the performance of the rockets, spacecraft, ground systems, and operations to ensure the systems are safe to fly astronauts.
The next launch of Cargo Dragon will probably take place at the end of November 2018 and will mark its first launch atop Falcon 9 Block 5, most likely with both a flight-proven booster and capsule.
"The next generation of American spacecraft and rockets that will launch astronauts to the International Space Station are nearing the final stages of development and evaluation".
Nicole Aunapu Mann is a California native and a lieutenant colonel in the Marine Corps.
The astronauts assigned to the Starliner's first mission are Sunita Williams, who retired as a Navy captain, and Cmdr. Dr Deepak Pandya, her father, said that she would start training for the 2019-20 mission. In December, Trump signed Space Policy Directive 1 to set the moon as NASA's next goal for astronauts. This will be Ms. Mann's first launch, having joined the astronaut corps in 2013.
As for being the only non-NASA guy on board, Ferguson explained later during a Reddit "Ask Me Anything" program that Boeing always uses company test pilots for first flights "and the Starliner is no exception". He is a Navy commander and test pilot with more than 3,500 flight hours in more than 40 aircraft.
Williams has spent 322 days in space as part of two expeditions: 14/15 and 32/33.
Mike Hopkins: Hopkins was raised on a farm near Richland, Missouri, and he has a master's in aerospace engineering.