The Russian-built Soyuz TMA-16 spacecraft, as photographed from the inside of the space station by Japanese astronaut Soichi Noguchi, after the ship undocked March 18, 2010.
NASA has signed a new $335 million contract with Russia to buy six extra seats on Soyuz spacecraft to launch ?American and partner astronauts into space after the space shuttle fleet is retired, the space agency announced Tuesday.
The new deal allows NASA to pay the Russian Federal Space Agency for six round-trip rides to and from the International Space Station in 2013 and 2014. That averages to about $55.8 million per trip ? a slight increase from the $50 million NASA paid for seats on the Russian-built Soyuz spacecraft through 2012.
After NASA's three-orbiter space shuttle fleet is retired this fall, American spaceflyers will have to rely on Russia for space transportation until U.S. commercial firms can build spaceships capable of carrying humans.
President Barack Obama is hoping the commercial ventures will come through.
In his 2011 budget request, President Obama proposed that NASA cancel its current plans for a post-shuttle space vehicle and instead invest in the private sector to encourage companies such as SpaceX, Virgin Galactic and others to develop spacecraft to carry astronauts to low-Earth orbit. That would free the agency to focus on more ambitious missions to the moon, asteroids or Mars, NASA officials have said.
The space shuttle Discovery is in orbit today on one of NASA?s final four shuttle missions scheduled before the fleet retires.
The new contract with Russia doesn't mean that NASA is counting out the commercial spacecraft, said NASA spokesman John Yembrick from the agency's headquarters in Washington, D.C.
"We're having redundant services," he told SPACE.com. "We always plan on purchasing a Soyuz vehicle to make sure we have access to the space station while commercial is progressing toward cargo and eventually crew capability. We're making sure that we're going to have access."
Since no commercial firm has yet launched humans into space, NASA cannot be sure when to expect alternative options to be ready.
And Russia requires a good deal of advance notice to make sure it will have Soyuz seats available, Yembrick said.
The new contract provides for the six astronauts to launch on four Soyuz vehicles in 2013 and return on two vehicles in 2013 and two in 2014. That will allow for roughly the same number of NASA crew members on the space station in 2013 as there are now.
"Right now we're keeping the crew of six with our partners and Russia to the same level it is now," Yembrick said, explaining that future space station crews will be composed of roughly the same proportions of Americans, Russians, Europeans, Canadians, and Japanese as they are now.
The contract also covers necessary astronaut training and preparation for the flights, and crew rescue if it is needed. The fee allows each astronaut to pack about 110 pounds (50 kilograms) of cargo on the trip up to space, and about 37 pounds (17 kg) for the return trip, plus trash.
NASA already has contracts in place with two American companies to provide unmanned cargo shipments to the space station in upcoming years.
The space agency has agreed to pay the California-based company Space Exploration Technologies (SpaceX) a total of $1.6 billion for 12 cargo delivery flights to the station using its Falcon 9 rockets and Dragon space capsules. The first Falcon 9 rocket is targeted to fly a test mission on May 8.
SpaceX officials have said in the past that its Dragon capsule has been designed to function as a crewed vehicle as well.
NASA has also signed a $1.9 billion deal with Orbital Sciences of Virginia for eight cargo shipments using the company?s unmanned Cygnus spacecraft and its Taurus 2 rocket. The first flight of a Cygnus vehicle is targeted for 2011.
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