Boeing was among three companies who bid for the next NASA contract to take astronauts into space. The company offered its CST-100 space capsule in the competition. (Boeing rendering)

NASA on Tuesday awarded a pair of much-anticipated contracts, worth up to $6.8 billion combined, to ferry astronauts to the International Space Station to Boeing and SpaceX in a deal that would allow the U.S. to launch astronauts into space from U.S. soil for the first time in years.

Speaking from the Kennedy Space Center in Florida, NASA Administrator Charles Bolden said the contracts set "the stage for what promises to be the most ambitious and exciting chapter in the history of NASA and human spaceflight.” Relying so heavily on contractors to take astronauts to space would allow the agency “to focus on an even more ambitious mission--that of sending humans to Mars,” he said.

The announcement of the “commercial crew” awards is a big step toward allowing the U.S. to end its reliance on Russia, which has been ferrying American astronauts to the space station since the retirement of the space shuttle three years ago. The arrangement hasn’t been cheap: the Russians currently charge $71 million per seat, and NASA has in a single year sent more than $400 million to Russia for these taxi rides. If the schedule doesn’t slip, and Boeing and SpaceX prove their vehicles are safe, NASA should see its astronauts launched on U.S. soil with American rockets by as early as 2017.

The awards represent a significant shift for NASA, which has long owned and operated its own rockets. Instead of going to space on government-owned vehicles, NASA’s astronauts would essentially rent space on ships provided by Boeing and SpaceX.

The contracts “highlight what commercial companies can accomplish and we are counting on them to deliver our most precious cargo,” said Kathy Lueders, NASA’s commercial crew program manager.

In addition to continuing to develop and test the companies’ vehicles, each contract calls for up to six flights to the space station once the ships are certified by NASA.

Boeing’s contract is worth up to $4.2 billion; SpaceX’s is valued at $2.6 billion. Lueders would not say exactly why Boeing received more but indicated that SpaceX proposed doing the work for less. Both contracts “have the same requirements and the companies proposed the value for which they were able to do the work, and the government accepted that,” she said.

For SpaceX, which is already the first private company to deliver cargo to the space station, the award is further evidence that it has transformed from start-up to a major a player in an industry long dominated by large, traditional companies, such as Boeing.

The two companies represent vastly different cultures in the space industry. Boeing is a so-called “old space” stalwart with decades of experience, contacts and lobbying might. SpaceX is the upstart California-based company founded by billionaire entrepreneur Elon Musk that has gleefully played the role of disrupter.

Musk, who also runs Tesla Motors, sued the Air Force earlier this year on a separate contract to launch military payloads, such as satellites, into space. He argued that SpaceX’s Falcon 9 rocket was a less expensive alternative that should be able to compete against the United Launch Alliance, the joint venture of Boeing and Lockheed Martin, which currently holds the contract.

Musk has relentlessly criticized Boeing for using the Atlas V, which uses a Russian-made engine.

United Launch Alliance is expected to counter that tomorrow by announcing that Blue Origin, the space startup founded by founder and Washington Post owner Jeff Bezos, would develop an American-made engine for the Atlas V, according to a person who is close to the arrangement who was not authorized to speak publicly.

Bezos and ULA chief executive Tory Bruno are scheduled to hold a news conference Wednesday afternoon at the National Press Club.

A ULA spokesperson did not respond to requests for comment. Blue Origin declined to comment.

Some lawmakers wanted NASA to go with a single company — and Boeing was always a front-runner. But others are pleased that the awards are going to two companies in an effort to foster competition and keep prices down.

“I think that’s the most important aspect of the decision -- that it is two companies,” said Michael Lopez-Alegria, the president of the Commercial Spaceflight Federation. “I’m more or less agnostic on which two companies but preserving competition is absolutely the right choice.”

Boeing offers a CST-100 capsule, which lands with parachutes and on cushions that deploy from the capsule. SpaceX’s Dragon capsule uses propulsion to land and can touch down, the company says, with the precision of a helicopter.

John Mulholland, vice president of commercial programs for Boeing Space Exploration, said the award was a natural extension of Boeing’s deacdes of work in the space program.

“We’re just really excited. We’re really proud to be able to continue our human spaceflight legacy. We’ve been partnering with NASA on every human spaceflight program dating back to Mercury,” NASA’s first manned-spaceflight program.

In a statement, Musk, who wants to colonize Mars, said the award “is a vital step in a journey that will ultimately take us to the stars and make humanity a multi-planet species."

Left out in the cold is Sierra Nevada Corp., which had developed a winged space plane known as the Dream Chaser that looked like a miniature space shuttle.

NASA hopes that investing government money into private enterprises will help touch off a broader commercial space industry. In addition to NASA, foreign governments, scientists and the super rich would also be able to buy seats on the ships, officials say.

Joel Achenbach contributed to this report.

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