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Sunday, December 2, 2007

The Device NASA Is Leaving Behind

After years of delays, NASA hopes to launch this week a European-built laboratory that will greatly expand the research capability of the international space station. Although some call it a milestone, the launch has focused new attention on the space agency's earlier decision to back out of plans to send up a different, $1.5 billion device -- one that many scientists contend would produce far more significant knowledge.

The instrument, which would detect and measure cosmic rays in a new way, took 500 physicists from around the world 12 years to build. But with room on the 10 remaining shuttle missions to the space station in short supply, many fear that it will remain forever warehoused on Earth, becoming the most sophisticated and costly white elephant of the space era.

As a result, the imminent launch of the $1 billion Columbus laboratory -- the kind of scientific workspace that the station's backers always said would be its reason for being -- will take place under something of a cloud.

"We are very excited about the launch of Columbus and believe this will be a major step forward for the international space station," said Martin Zell, who is involved with the European space laboratory as head of research operations for the European Space Agency and is also a coordinator for development of the cosmic ray project.

"But if the [other device] does not make it to the station, it will be a very great setback for the space community and the ISS," Zell said. "It would be the most visible, perhaps the most exciting, experiment on the station."

While the Columbus laboratory will allow scientists to conduct long-term biological, fluid and materials science research in weightless conditions, the cosmic ray detector -- called the Alpha Magnetic Spectrometer (AMS) -- would look for evidence of how the universe formed. It would search in particular for evidence of the existence and workings of dark matter and antimatter, which theorists have concluded must exist but have never been identified or measured.

The science is considered innovative and important -- a major Department of Energy scientific review recently concluded that it "may well make some fundamental discoveries." But the fate of the instrument also has significant implications for international cooperation in space.

"The credibility of the United States is at stake here, because NASA made a commitment to bring Columbus and AMS to the space station," said Samuel C.C. Ting, a Nobel laureate at the Massachusetts Institute of Technology who conceived the project in 1994 and drew in collaborators from 60 institutes in 16 nations to build and fund it. "After all this work, it would be a terrible blow if the instrument cannot be used."

Given all that has happened with the shuttle program, there is no reason to throw harsh words at NASA about this," said Giovanni Bignami, president of the Italian Space Agency, which has played a major role in developing the AMS. "But that said, it would be a true international disgrace if this instrument ends up as a museum piece that never is used."

The space station was built with four attachment sites that can mount experiments that need direct exposure to space -- and one was designated for the AMS. The project was sponsored by the Department of Energy in 1995, and NASA made a signed commitment to deliver the instrument to the station. Ting said the nations that collaborated on the project did so only because NASA promised delivery.

But that was before technical and funding problems slowed assembly of the space station, and before the loss of the Columbia shuttle and its crew on Feb. 1, 2003, halted all shuttle missions for 2 1/2 years. President Bush's 2005 manned exploration initiative -- which aims to develop a new spacecraft to travel to the moon and later to Mars -- formally lowered the priority of doing basic science on the station. The AMS was bumped soon after.

NASA Administrator Michael D. Griffin has been firm in saying that the shuttles will be retired in 2010 -- in large part because NASA needs the funds to pay for the new spacecraft -- and that finishing assembly of the station, at an estimated cost of $100 billion over two decades, is the top priority for the remaining shuttle missions. Griffin initiated a study last year into alternative ways to deliver the AMS to the station, but they proved to be prohibitively expensive.

Despite the strong possibility that the instrument will never be used, NASA continues to contribute to its assembly, which is being completed in Geneva. The agency will have spent $75 million on the project by the time it is finished and shipped to the Kennedy Space Center late next year, said NASA project manager Mark Sistilli.

We're always looking for ways to get it up to the station," Sistilli said. "But given our constraints now with the shuttle program, the agency is in a real quandary."

The AMS is an automated device with a specific set of scientific tasks. The Columbus lab scheduled to be launched next week is a more like a "shirtsleeves" lab that includes specially designed work areas for a wide range of experiments.

Many of the 16 racks in the 23-foot-long lab have experiments in place -- to study the effect of weightlessness on the root systems of plants, the dynamics of fluids in space, how crystals grow without gravity and other questions. Zell, at the European Space Agency, said scientists once thought they could perfect and mass-produce metals in space, but that is no longer considered feasible. But the zero-gravity experiments can teach researchers how to make better metals, or crystals, on Earth, he said.

Columbus will not be the first science lab at the space station; the American Destiny lab was flown to the station in 2001. But scientific experimentation has been limited, in part because the small crew spends most of its time keeping systems running properly, and because the U.S. science mission on the station formally changed in 2005 after Bush announced his exploration initiative.

American science on the orbiting facility is now dominated by research into how months or years in space will affect the human body and what can be done to limit the health effects.

One study of salmonella bacteria in space was recently published in the Proceedings of the National Academy of Sciences and drew significant attention. Researchers from Arizona State University sent the salmonella on a 2006 shuttle mission and found that the bacteria became far more virulent while in space. The scientists later identified a protein involved in the change -- research that may help in space missions while yielding clues on how to better treat and contain salmonella on Earth.

The Columbus lab will get relatively limited crew time, at least until 2009, when the crew size is to increase from three to six. According to Zell, the experiments on Columbus range from those that are largely mechanical and computerized to life science and crystal experiments that require frequent human involvement. The lab, designed to last 10 years in orbit, will have several small, unpressurized pods that will expose bacteria and metals to the radiation, vacuum and extreme temperatures of space; another will monitor and measure solar radiation.

Nobel laureate Steven Weinberg, a theoretical physicist at the University of Texas, is one of many researchers frustrated by the priorities NASA has set, and he has publicly discussed the AMS issue as a prime example of what he thinks has gone wrong. If the instrument were ferried to the station, he said, its study of cosmic rays "would be the only significant science ever done on the space station."

"This device could make discoveries that are Earth-shattering," he said. "We have an opportunity now to do some worthwhile fundamental science on the ISS, and they're resolutely turning their back on it."

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