Nasa plans to use €35 million of federal economic stimulus funds to seed development of commercial passenger transportation service to space, agency officials said.
Aspiring spaceship operators will have 45 days to submit proposals, which will be competitively evaluated. Awards for the Commercial Crew Development programme are expected to be announced before the end of September.
The US is retiring its fleet of space shuttles next year after seven more missions to complete construction of the €70 billion International Space Station, which orbits about 225 miles above earth.
After that, the US plans to buy rides for astronauts to and from the station from Russia, one of the 16 nations involved in the station programme.
Nasa is spending €353 million to help two US firms, Space Exploration Technologies, a privately held company known as SpaceX, and Orbital Sciences Corp., develop rockets and capsules to deliver cargo to the station.
SpaceX's contract includes an option to upgrade its Dragon cargo ship for passenger service. The company has said it needs €212 million, most of which would be used to develop a launch escape system for the crew.
"It's a little disappointing that (the new programme) is only €35 million," said SpaceX founder and chief executive officer Elon Musk. "Fifty million is what it costs for one seat on the (Russian) Soyuz."
Nevertheless Musk hailed the move as a step in the right direction.
"The main thing that the public should be taking note of is that right now we are (solely dependent) on the Russians (for space transports) after 2010," he said.
The White House has convened a panel, headed by former Lockheed Martin chief Norm Augustine, to review Nasa's human space program. The current plan is to finish the station next year, retire the shuttles and develop new vehicles that can travel to the space station as well as to the moon and other destinations in the solar system.
Funding for the follow-on program has been scaled back to €57 billion from €76 billion between next year and 2020, the year pegged for the first post-Apollo moon landing.
Members of a presidential panel reviewing the country's human space programme said last week that given current budget forecasts and no changes in the programme, a moon landing would not occur until the mid 2020s at the earliest.
The panel, which is scheduled to make its report by the end of this month, also has been mulling extending the life of the space station beyond its projected shut-down date of 2015.
In addition to scientific uses, having a station in orbit will serve as a market to stimulate commercial space development, said board member Jeff Greason, the co-founder and head of XCOR Aerospace.