These are the space taxis of the future selected by NASA

By the end of 2017, it will be “taxis” from the private companies Boeing and SpaceX that will take NASA astronauts into space.

The US space agency has just signed a contract with these private companies worth US$6.8 billion to help finish construction of the new spacecraft, which is to house a team of seven astronauts.

Ever since NASA unveiled its spacecraft program in 2011, Americans have relied on Russia and its Soyuz vehicles for travel to the International Space Station (ISS).

But disagreements with the Moscow government over recent events in Ukraine have given an increasingly bitter taste to existing agreements on the use of the Soyuz by the United States.

There’s also the question of price per flight: Russia charges $70 million per astronaut, a sum that US officials consider excessive.

“From day one the Obama administration made it clear that the greatest nation on Earth should not depend on other nations to go into space,” NASA Administrator Charlie Bolden told reporters.

“Thanks to President Obama’s leadership and the hard work of NASA and our industry teams, today we are one step closer to launching our astronauts into space from US soil on US spacecraft, and ending our complete reliance on Russia by 2017,” he said.

In 2010, President Obama tasked NASA with “seeding” resources into competent domestic companies to restore US capability.

Since being entrusted with this mission, the space agency has dished out nearly $1.5 billion in investment.

Most of those funds went to three private companies: Boeing, in Texas; SpaceX of California, and the Colorado-based Sierra Nevada Corporation (SNC).

Ideally, NASA would have wanted to continue investing in all three companies, but resources didn’t go all the way and it had to pick its favourites.

What will the ships be like?

The Crew Space Transportation CST-100 will be able to take seven people to the ISS.

The ship is designed to go into space aboard an Atlas V rocket from Cape Canaveral, Florida.

To return to Earth you will have the assistance of a heat shield and a parachute.

At a superficial level it has certain similarities with the Apollo system, of course with state-of-the-art technology.

SpaceX already operates an unmanned freight transport system to the ISS.

In 2012 it carried out the first private transport mission to the ISS in history, and at the end of September 2014 it will make its fourth trip.

Looking ahead to 2017 SpaceX is working on an update of this ship to include the transport of humans.

Under the contract signed this week, NASA would give SpaceX $2.6 billion to complete the Dragon manned spacecraft project.

But that funding is far less than the $4.2 billion Boeing will receive for its CST-100.

Part of NASA’s strategy in outsourcing transportation to the ISS to the private sector is wanting to free up budget to work on more ambitious space exploration missions.

The agency is leading the development of a super rocket and capsule that could travel much farther into the solar system, to the Moon and Mars.

This rocket, called the Space Launch System (SLS), and the crew vehicle, called the Orion, are too large to perform regular “taxi” duties to the ISS.

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