By KENNETH CHANG
Published: August 3, 2010
When a cooling-system pump on the International Space Station broke down over the weekend, NASA and the six astronauts on board responded with typical cool self-assurance. The space agency scheduled two spacewalks to repair the damage and said the astronauts, three Americans and three Russians, were in no danger.But the incident underlined a deeper concern about the orbiting station’s long-term health. If this or any other problem should result in a need to abandon the station, the United States’ human spaceflight program would lose one of its last remaining reasons for being.Until recently, the 12-year-old space station was an afterthought in the multiyear, multibillion-dollar effort to return people to the Moon and possibly push off to Mars. But in the shifting priorities under the Obama administration, the station has become a keystone.Not only is it supposed to serve as a scientific laboratory and an example of successful international collaboration, the administration also wants it to provide a market to nurture a commercial space industry for launching people and cargo into orbit.“It has a much more central role in this decade under the Obama plan than it did under the Bush plan,” said John M. Logsdon, former director of the Space Policy Institute at George Washington University.NASA’s Moon program, known as Constellation, has been hamstrung. Although pieces of it could survive in bills under consideration in Congress, it remains unclear what rockets NASA is to build, what their destinations would be and how long it would take to get there.Without the space station, NASA’s financing of commercial rockets to take crew and cargo there would almost certainly evaporate. And without government financing, companies would be unlikely to invest billions of dollars to pursue a speculative market.“There’s no question it’s a risky business strategy,” said James A. M. Muncy, a space policy consultant who supports the Obama space policy.Scott Pace, the current director of the Space Policy Institute, said abandoning the station might even mark the end of the human spaceflight program.“My concern,” he said, “is without an overarching political impetus, the energy to restart a human spaceflight program would be very hard to achieve.”A Congressional aide, who was not authorized to speak for attribution, said, “You’re in a position where we were in 1962, where you don’t have a place to go.” With the remaining space shuttles to be retired next year, he said, “you don’t even have a launch vehicle that can travel to low-Earth orbit.”The cooling problem, which has limited research aboard the space station so equipment does not overheat, is only the latest glitch to befall it. In the past, navigation computers have crashed, a rotating joint on the solar arrays started grinding and vibrating, and the toilets have not always worked. In each case, engineers identified the problem and found a solution.“I.S.S. is a living, breathing beast,” Michael T. Suffredini, the space station manager, said in an interview last month. “Some days everything doesn’t exactly work perfectly.”Still, NASA officials say that over all the station is in good shape, even as its lifetime is being extended five years, to 2020.Over the past few years, in preparation for life after the space shuttle, NASA has launched as many of the large spare parts as it could and stored them on the outside of the station. The station has four spare pumps of the type that failed Saturday, and managers said they had planned for exactly this type of failure.Mr. Suffredini said that only a radiator was too large to fit into any spacecraft other than the shuttle, and that piece is to fly up on the next shuttle mission in November. Equipment on the station has also been lasting longer than predicted, he said, adding, “If we get thrown curveballs along the way, we have time to react to them.”The cooling pump was an exception: Expected to last 100,000 hours (more than 11 years), it failed after only about 80,000 hours.Without the shuttles, it will not be possible to bring parts back to Earth for diagnosis and repair. That could be significant for something like the pump. There is no room to bring the faulty pump back on the next two shuttle missions, but it could be brought back on an additional flight that is likely to be added to the schedule for next summer.The threat of a collision with micrometeoroids is small, but not zero. Mr. Suffredini said the chances of a strike severe enough to require evacuation were about 1 in 100 over a six-month period. Over 10 years, the cumulative risk is nearly 1 in 5.The Senate bill outlining the budgets and goals for NASA for the next three years asks the space agency to conduct a detailed study to ensure that it is prepared for operating the station until 2020.“The recent breakdown of the station’s cooling system emphasizes how critical it is that we understand all of the equipment needs the space station will have as its service life is extended,” Senator Kay Bailey Hutchison of Texas, who pushed for that provision, said in a statement. “We must assure that NASA has a plan to deliver those elements or bring parts down for analysis and repair once the space shuttle is finally retired.”The Senate bill also calls for refurbishing an additional shuttle fuel tank, which leaves the door open for at least one more shuttle flight if it becomes necessary.NASA, via Associated Press
When a cooling-system pump on the International Space Station broke down over the weekend, NASA and the six astronauts on board responded with typical cool self-assurance. The space agency scheduled two spacewalks to repair the damage and said the astronauts, three Americans and three Russians, were in no danger.
But the incident underlined a deeper concern about the orbiting station’s long-term health. If this or any other problem should result in a need to abandon the station, the United States’ human spaceflight program would lose one of its last remaining reasons for being.
Until recently, the 12-year-old space station was an afterthought in the multiyear, multibillion-dollar effort to return people to the Moon and possibly push off to Mars. But in the shifting priorities under the Obama administration, the station has become a keystone.
Not only is it supposed to serve as a scientific laboratory and an example of successful international collaboration, the administration also wants it to provide a market to nurture a commercial space industry for launching people and cargo into orbit.
“It has a much more central role in this decade under the Obama plan than it did under the Bush plan,” said John M. Logsdon, former director of the Space Policy Institute at George Washington University.
NASA’s Moon program, known as Constellation, has been hamstrung. Although pieces of it could survive in bills under consideration in Congress, it remains unclear what rockets NASA is to build, what their destinations would be and how long it would take to get there.
Without the space station, NASA’s financing of commercial rockets to take crew and cargo there would almost certainly evaporate. And without government financing, companies would be unlikely to invest billions of dollars to pursue a speculative market.
“There’s no question it’s a risky business strategy,” said James A. M. Muncy, a space policy consultant who supports the Obama space policy.
Scott Pace, the current director of the Space Policy Institute, said abandoning the station might even mark the end of the human spaceflight program.
“My concern,” he said, “is without an overarching political impetus, the energy to restart a human spaceflight program would be very hard to achieve.”
A Congressional aide, who was not authorized to speak for attribution, said, “You’re in a position where we were in 1962, where you don’t have a place to go.” With the remaining space shuttles to be retired next year, he said, “you don’t even have a launch vehicle that can travel to low-Earth orbit.”
The cooling problem, which has limited research aboard the space station so equipment does not overheat, is only the latest glitch to befall it. In the past, navigation computers have crashed, a rotating joint on the solar arrays started grinding and vibrating, and the toilets have not always worked. In each case, engineers identified the problem and found a solution.
“I.S.S. is a living, breathing beast,” Michael T. Suffredini, the space station manager, said in an interview last month. “Some days everything doesn’t exactly work perfectly.”
Still, NASA officials say that over all the station is in good shape, even as its lifetime is being extended five years, to 2020.
Over the past few years, in preparation for life after the space shuttle, NASA has launched as many of the large spare parts as it could and stored them on the outside of the station. The station has four spare pumps of the type that failed Saturday, and managers said they had planned for exactly this type of failure.
Mr. Suffredini said that only a radiator was too large to fit into any spacecraft other than the shuttle, and that piece is to fly up on the next shuttle mission in November. Equipment on the station has also been lasting longer than predicted, he said, adding, “If we get thrown curveballs along the way, we have time to react to them.”
The cooling pump was an exception: Expected to last 100,000 hours (more than 11 years), it failed after only about 80,000 hours.
Without the shuttles, it will not be possible to bring parts back to Earth for diagnosis and repair. That could be significant for something like the pump. There is no room to bring the faulty pump back on the next two shuttle missions, but it could be brought back on an additional flight that is likely to be added to the schedule for next summer.
The threat of a collision with micrometeoroids is small, but not zero. Mr. Suffredini said the chances of a strike severe enough to require evacuation were about 1 in 100 over a six-month period. Over 10 years, the cumulative risk is nearly 1 in 5.
The Senate bill outlining the budgets and goals for NASA for the next three years asks the space agency to conduct a detailed study to ensure that it is prepared for operating the station until 2020.
“The recent breakdown of the station’s cooling system emphasizes how critical it is that we understand all of the equipment needs the space station will have as its service life is extended,” Senator Kay Bailey Hutchison of Texas, who pushed for that provision, said in a statement. “We must assure that NASA has a plan to deliver those elements or bring parts down for analysis and repair once the space shuttle is finally retired.”
The Senate bill also calls for refurbishing an additional shuttle fuel tank, which leaves the door open for at least one more shuttle flight if it becomes necessary.
NASA, via Associated Press
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