NASA authorized on Friday the launch next Wednesday of a SpaceX rocket with two astronauts on board, on the first US manned flight since 2011.
"NASA's SpaceX Crew Dragon mission launch has a green light"the US space agency tweeted.
Senior officials from NASA and the company owned by Elon Musk had been meeting since Thursday at the Kennedy Space Center, in Florida, to verify that everything was ready and safe for the mission.
Robert Behnken and Douglas Hurley will take off on May 27 at 4:33 p.m. (8:33 p.m. GMT) aboard a Crew Dragon capsule bound for the International Space Station (ISS), which they will dock the next day.
It is the first one hundred percent American manned mission since the end of the space shuttle program in 2011, after 30 years of service.
Since then, only Russia had the capacity to take the ISS - permanently occupied since 2000 - to dozens of astronauts, both American and from other countries, in the Soyuz rockets launched from the Baikonur cosmodrome in Kazakhstan.
Starting with the presidency of Barack Obama (2009-2017), NASA financed contracts with SpaceX for $ 3.1 billion and with Boeing for $ 4.9 billion to return to the United States the ability to travel on its own into space.
The show originally marked the return of American space transportation for 2015.
Neil Armstrong, the first man to walk on the Moon, described in 2010 as "humiliating and unacceptable" that the United States had not resumed space travel.
If next Wednesday's mission is successful, the hiatus will have been almost nine years.
SpaceX and Boeing will have to make six trips to the ISS with four astronauts in the coming years, not counting the demo mission.
If you are successful in this mission -called Demo-2, after Demo-1 launched without incident in March 2019 with a mannequin on board- SpaceX will be the first private company to transport astronauts to the ISS.
Doug Hurley and Bob Behnken have been training for five years for the mission of the Crew Dragon capsule, inside which everything is controlled by touch screens.
Like the Apollo capsules of the 1960s, Crew Dragon will land on Earth again.
With information from AFP
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