KOUROU, French Guiana — European government officials on Feb. 13 said they would attempt to push ahead with their ExoMars missions to Mars in NASA’s absence by reinforcing their cooperation with Russia.

With NASA’s 2013 budget now saying formally what had been whispered for weeks — the U.S. agency is pulling out entirely of a planned 2016 mission and cannot commit to the follow-on 2018 mission — the European Space Agency finds itself between a rock and a hard place.

The agency does not want to end industrial work on the two missions and lose its past investment. Delaying the launches to 2018 and 2020 is also rejected because “it would mean keeping industrial teams together for two additional years, and cost a lot more money,” ESA Director-General Jean-Jacques Dordain said.

But moving forward likely will mean ESA needs to find extra money for a project that has been unable to complete its funding despite more than three years of effort. ESA has rounded up 850 million euros ($1.1 billion) in support for ExoMars, led by Italy. The mission, as designed with NASA’s involvement, was estimated to cost ESA 1 billion euros.

ExoMars has had funding difficulties in Europe since it was first proposed nearly a decade ago. Those problems were not solved by NASA’s participation, and they remain serious enough to cast doubt on ExoMars even if Russia steps in as a major partner.

The Russian space agency, Roscosmos, has indicated it would be willing to fill at least part of the role that ESA until recently assumed would be NASA’s. Pending final negotiations between ESA and Roscosmos, two Russian Proton vehicles could be ready for the 2016 and 2018 launches, replacing two NASA-provided Atlas rockets.

But what Russia cannot provide in NASA’s place is a Mars landing system for an ESA-built rover planned for the 2018 launch. Under the scenario with NASA, the U.S. and European agencies would divide work on a rover and use NASA’s Sky Crane landing system.

“Russia can replace just about everything NASA was going to provide for ExoMars except the lander,” Dordain said in an interview here following the successful inaugural flight of ESA’s Vega small-satellite launcher. “That is something we would have to develop, so already I know that ExoMars without NASA is going to cost us more than with NASA. How much more remains to be seen.”

NASA officials have told their European counterparts that while the fiscal-year 2013 budget proposal released Feb. 13 ends all hope of a NASA role in a 2016 launch, there remains some possibility of NASA involvement in the 2018 mission.

What kind of role NASA might play, and when that might be decided, remains unclear. “I will always welcome NASA into ExoMars,” Dordain said. “But what I cannot do now is let NASA’s decision-making process determine our development schedule.”

The Italian Space Agency (ASI) has led ExoMars development from the start. Italy’s government debt crisis complicates any ASI attempt to increase its funding, but ASI President Enrico Saggese said his agency’s backing for the project remains as solid as ever.

The U.S. government’s treatment of ExoMars in the 2013 budget highlights the fact that “cooperation with NASA is at a low ebb,” Saggese said in an interview here. “If I have correctly understood the situation, cooperation with Europe is taking a major portion of the budget cut.”

Saggese, whose agency has been among the most steadfast partners of NASA in Europe, both on scientific satellites and on the international space station, said he wondered whether NASA would be so quick to abandon ExoMars if Europe had already demonstrated its capability to land on another planet.

“In ExoMars, we were asking NASA to cooperate in an area that NASA has already mastered,” Saggese said, referring to NASA’s previous successes in landing rovers on Mars. “You don’t ask a champion bridge player to sit down and play with someone just learning to shuffle cards. We need to go to Mars and we need to maintain the 2016 and 2018 dates.”

Saggese said talks between Europe and Russia on Mars exploration might be widened to include a lunar lander, which Germany wants to build, combined with an ExoMars mission and a follow-on to Russia’s failed Phobos-Grunt spacecraft, which was designed to return samples from Mars’ larger moon, Phobos.

Dordain said ESA would deliver to its member governments, in mid-March, an estimate of the cost of ExoMars without NASA but including a European-built lander. ExoMars also was designed to include an entry, descent and landing module on the 2016 flight, whose main payload would be a European-built Mars telecommunications orbiter.

March is also the month when ESA’s current ExoMars development contract with Thales Alenia Space ends, and must be extended or canceled.



French Space Agency Sends Mixed Signals on ExoMars

ExoMars Partnership Inches Forward

ESA Formally Invites Roscosmos To Join ExoMars Mission as Full-fledged Partner 

Peter B. de Selding was the Paris bureau chief for SpaceNews.