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US, Europe to team up for future Mars trips

(Agencies)
Updated: 2009-06-09 17:02

Talk of a possible marriage has unnerved some space advocates who worry a union will decrease competition and cause the US to lose its edge, holding it hostage to foreign politics.

"NASA should be showing off its stuff and not saying, 'We can't do it unless we have the cooperation,'" said Robert Zubrin, a former Lockheed Martin Corp. engineer who now heads the Mars Society advocacy group.

The trans-Atlantic dialogue comes at a critical point. NASA is polishing a new public relations message to replace its decade-old focus on finding water. At the same time, Mars is facing competition from other solar system bodies emerging as promising places to search for signs of life.

While international pairings are nothing new, they tend to be more common on deep space missions. NASA united with the European and Italian space agencies to launch the Cassini-Hguyens mission to Saturn and its moon Titan. Earlier this year, NASA and the European agency announced plans to be partners on a 2020 mission to Jupiter's ice-covered moon Europa.

With Mars, however, NASA has kept a do-it-yourself attitude while letting other countries add instruments to NASA spacecraft for their own data-gathering. That NASA and the Europeans are considering pooling resources reflects a budget reality: It has become too expensive for one nation to pay to go to Mars alone, especially with a long-term goal of returning Martian rocks and soil to Earth estimated to cost at least $5 billion.

The growing pains afflicting the US Mars program are partly due to it being a victim of its own success. Past missions have raised more questions about whether the planet once had an environment that could support microbial life. To get answers requires more expensive study.

The early American Mars missions were quick flybys. In 1965, Mariner 4 became the world's first spacecraft to return 21 close-up images. The failures of an orbiter and lander in 1999 led to a revamp of the program.

The last decade arguably has been the golden age of Mars exploration. The plucky twin rovers Spirit and Opportunity are still active after five years. Before it froze to death last year, the Phoenix lander gathered up ice and tested water.

"Now the question is, where do we go from here?" said Scott Hubbard, a former NASA Mars czar who teaches at Stanford University.

Arizona State University Mars scientist Phil Christensen believes a partnership is inevitable given the cost, but he would rather see the space agencies collaborate after 2016.

"We're very close to the point where we can't keep on doing it alone," he said.

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