European governments remain uncertain about whether they want to finance an independent manned spaceflight program given its costs, although they have left open the possibility of working with Russia.

In recent weeks, European Space Agency (ESA) officials appear to have backed away from earlier proposals that Europe develop its own ability to launch astronauts from its Guiana Space Center, and to have them visit a European facility in low Earth orbit that could succeed the international space station.

A call by ESA managers in late 2007 for just such a program, to be presented to European governments at next November's conference on space strategy and budgets, appears to have met with resistance from the national governments that will have to pay for it, European government officials said.

ESA already has committed about 4 billion euros ($5.9 billion) to be spent in the next decade just to meet its obligations to the international space station. The agency is hoping to secure additional flights of its astronauts to the station aboard the U.S. space shuttle or Russia's Soyuz capsule. But this is likely to be possible only by investing in additional hardware that could be bartered against slots for European astronauts.

Europe's Columbus laboratory is scheduled for launch to the station aboard a U.S. space shuttle in the coming days, and ESA is focusing on how to maximize the investment in the space station.

Alan Thirkettle, ESA's space station program manager, said the agency has spent about 5 billion euros on the space station, including the Columbus facility, since 1995. The investment includes providing station hardware as partial compensation for Europe's obligation to finance 8.3 percent of the station's common resources.

In a Jan. 29 presentation here, Thirkettle said ESA's early priority, once Columbus is in orbit at the station, is to increase the amount of time European astronauts can spend at the station. ESA's station ownership share gives it the right to launch one European astronaut every two years, for a stay of six months, assuming there is a station crew of three Russian and three non-Russian astronauts. Europe's 8.3 percent ownership is calculated based on the non-Russian part of the station.

The station currently is scheduled to increase its astronaut complement to six from the current three in mid-2009.

Thirkettle said the agency is weighing several possible proposals to the November ministerial conference that could double the amount of European astronaut time at the station, to one six-month mission every year.

The agency has opened discussions with the Italian Space Agency on using Italy's right to astronaut time at the station on behalf of the entire European program. As part of a bilateral agreement with NASA, the Italian government built the station's Multi-Purpose Logistics Module, with promised Italian astronaut time as part of the payment.

Since that deal was struck, the several individual nations that had their own astronauts — France, Germany and Italy — have merged their programs into ESA's European Astronaut Corps, which is based in Cologne, Germany.

"We would like to get to the equivalent of one flight per year if we can add the Italian and the European astronaut time," Thirkettle said.

The 4 billion euros on the station that ESA currently expects to spend includes about 250 million euros in annual operations charges and 100 million euros per year in science and technology experiments, Thirkettle said. The remaining portion is to build and launch Europe's Automated Transfer Vehicle space tug, which was built in lieu of paying NASA cash for Europe's station obligations.

Whether there will be much room in the agency's budget for additional astronaut-related missions is uncertain.

For 2008, human spaceflight accounts for 8.7 percent of ESA's annual budget of 3 billion euros.

European governments have agreed to fund initial studies on whether a crew-transport vehicle could be built in cooperation with Russia without transferring funds to Russia and without ceding program control to Russia.

ESA Director-General Jean-Jacques Dordain said ESA's negotiations with the Russian space agency, Roskosmos, have encountered roadblocks both in Europe and in Russia.

In a Jan. 14 briefing, Dordain said he still is unsure of whether ESA governments want to finance the crew-transport capsule with Russia, or whether Russia wants to embark on a Euro-Russian effort.

"The uncertainties exist on both sides," Dordain said. "And we need to look at a Plan B if we can't agree on financing or on who does what. The uncertainties involve both the mission of the vehicle and the question of who builds what part of it."

ESA's biggest contributor, France, which in the past has invested heavily in its own astronaut program, also appears hesitant about whether Europe needs to start investing in a crew-transport capability.

In a detailed presentation of what the French space agency, CNES, views as its near-term priorities, almost no mention was made of astronaut-related programs beyond what already is planned for the space station.

CNES President Yannick d'Escatha said studies should continue on crew-transport options, but he stressed that he saw no need to make a decision this year. "We certainly should not shut the door on these possibilities both in Europe and with other partners," d'Escatha said. "But first we must assure that we use Columbus in the most intelligent way possible."

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