By 2017, there will be two new spacecraft capable of launching man from U.S. soil: SpaceX’s Dragon and Boeing’s CST-100. Now, NASA has selected the pioneering astronauts that will fly on these vehicles for the first time, ushering in a new era of space travel.

Both companies are being funded by NASA’s Commercial Crew Program to develop manned vehicles to reach the International Space Station (ISS) in orbit, and possibly other destinations in the future. With the retirement of the Space Shuttle in 2011, NASA decided to invest heavily in private companies to take astronauts into Earth orbit, while the agency itself focuses on getting astronauts to an asteroid and Mars using its Orion spacecraft and upcoming Space Launch System rocket.

At the moment, NASA relies on Russia to launch astronauts aboard the Soyuz spacecraft to the ISS, so it is keen to get launches back into its own country. “These distinguished, veteran astronauts are blazing a new trail – a trail that will one day land them in the history books and Americans on the surface of Mars,” said NASA Administrator Charles Bolden in a statement.

The four astronauts selected all have considerable experience behind them. Robert Behnken, 44, is a U.S. Air Force Colonel that has flown previously on two Space Shuttle missions. Eric Boe, 50, also flew on two Space Shuttle missions.

Douglas Hurley, 48, was the pilot for two Space Shuttle missions, including the final launch of the program in July 2011. Sunita Williams, 49, has spent two long-duration stays on the ISS, totalling 322 days in space, and holds the record for the most spacewalk time by a female astronaut: 50 hours and 40 minutes.

^{SpaceX recently completed the first unmanned launch abort test of its Dragon spacecraft, pictured here. Credit: SpaceX}

In a blog post, Bolden revealed that these private launches would be cheaper than their Russian counterparts, $58 million (£37 million) per astronaut compared to $76 million (£49 million), since four astronauts can be carried to the ISS on each launch rather than three on the Soyuz. However, only two astronauts will be on board for the initial flights in 2017. SpaceX and Boeing will fly their own astronauts alongside NASA's selections, with the latter training to use both vehicles as they don't yet know which spacecraft they will be selected for.

“Congratulations to Bob, Doug, Eric and Suni on being the first group of astronauts selected for flight training as part of NASA’s Commercial Crew Program,” said Gwynne Shotwell, President and COO of SpaceX, in a statement.

“We look forward to working with such a highly-skilled and experienced group of NASA astronauts as we carve a path forward to launch in 2017,” added John Elbon, Boeing Vice President and General Manager of Space Exploration.

Last September, NASA whittled down the competitors for its Commercial Crew Program – cutting off Sierra Nevada Corporation’s Dream Chaser, although they will still provide some funding for it – and awarded SpaceX and Boeing significant funding to develop their spacecraft: $2.6 billion (£1.7 billion) and $4.2 billion (£2.7 billion) respectively. SpaceX will launch its capsule on its own Falcon rocket, while Boeing will initially use the United Launch Alliance’s (ULA) Atlas V rocket, but could use others in the future.