Nasa has successfully sent its astronauts to the International Space Station (ISS) in a commercially built and operated American crew spacecraft.

The Crew Dragon spacecraft was built by aerospace manufacturer and space transportation services provider SpaceX.

The two astronauts on board are Robert Behnken and Douglas Hurley. The spacecraft lifted off on SpaceX’s Falcon 9 rocket from Launch Complex 39A at Nasa’s Kennedy Space Centre in Florida.

Nasa Administrator Jim Bridenstine said: “Today, a new era in human spaceflight begins as we once again launched American astronauts on American rockets from American soil on their way to the International Space Station, our national lab orbiting Earth.

“I thank and congratulate Bob Behnken, Doug Hurley, and the SpaceX and Nasa teams for this significant achievement for the United States.

“The launch of this commercial space system designed for humans is a phenomenal demonstration of American excellence and is an important step on our path to expand human exploration to the Moon and Mars.”

The Nasa’s SpaceX Demo-2 mission is the first with astronauts onboard. It proves the performance of all the aspects of the SpaceX crew transportation system, including launch, in-orbit, docking and landing operations.

The mission will enable Nasa’s Commercial Crew Program to certify Crew Dragon.

Upon conclusion of the mission, the spacecraft along with the two astronauts will leave the ISS and re-enter Earth’s atmosphere.

SpaceX chief engineer Elon Musk said: “This is a dream come true for me and everyone at SpaceX. It is the culmination of an incredible amount of work by the SpaceX team, by Nasa and by a number of other partners in the process of making this happen.”