SpaceX hit a big milestone on Friday with NASA confirming on Friday that the Elon Musk-led space cargo business will launch astronauts to the International Space Station by 2017.

Last year, the space agency tentatively awarded a $2.6 billion contract to SpaceX to carry crew to space. NASA’s announcement on Friday formalizes the deal, which involves SpaceX loading its Crew Dragon spacecraft with astronauts and sending them beyond the stratosphere.

NASA’s goal is to wean the country’s space program from its dependence on Russia for sending astronauts into orbit. The space agency plans to award two more private contracts for manned flights to the space station sometime in the future.

Prior to the SpaceX contract, NASA gave a $4.2 billion contract to Boeing BA for shuttling astronauts to the International Space Station.

“It’s really exciting to see SpaceX and Boeing with hardware in flow for their first crew rotation missions,” Kathy Lueders, manager of NASA’s Commercial Crew Program, said in a statement. “It is important to have at least two healthy and robust capabilities from U.S. companies to deliver crew and critical scientific experiments from American soil to the space station throughout its lifespan.”

NASA has yet to decide whether Boeing or SpaceX will be the first to blast off to the International Space Station. Absent the necessary funding by the U.S. government, the space agency said it would have to postpone the commercial spacecraft missions.

NASA said that SpaceX’s Crew Dragon spacecraft and its related rocket passed the initial design reviews and certifications to proceed to the next level of testing, which is needed to show that the spacecraft is safe enough to carry astronauts. The space agency said that a standard mission consists of flying four astronauts to the space station, where they would remain for 210 days.

This is a big deal for SpaceX because it previously only launched unmanned spacecraft to the space station to transport supplies. This summer, one of SpaceX’s unmanned spacecraft exploded en route to the space station.

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