Edmonton Journal February 16, 2003
Shaky foothold in space: It's lonely up there
The loss of the space shuttle Columbia could doom the most expensive engineering endeavour in history --the $100B International Space Station
SOURCE: New York Times
By Andrew C. Revkin
The grounding of the three remaining space shuttles after the Columbia's destruction poses enormous, and potentially calamitous, challenges for the International Space Station and the 16 countries trying to maintain it as a permanent foothold in space.
All of the shuttle launchings scheduled for this year and early 2004 were missions to ferry crews or components to the station, which has been under construction since 1998. Now this schedule is in total disarray.
"Everything is on hold," said Benoit Marcotte, manager of Canada's space station program at the Canadian Space Agency. "The leadership is looking at the options." If delays persist for a year or more, some experts says it may even become difficult to prevent the $100-billion station -- the most expensive engineering project in history -- from falling into Earth's atmosphere. Until now, occasional nudges from the shuttle have helped keep it from sinking under the tug of friction as it skims the outermost ether.
For the moment, as investigators continue to scour eastern Texas and Louisiana for fragments of Columbia, some 392 kilometres overhead the station loops the world every 90 minutes.
On Feb. 4 its crew of two Americans and one Russian -- officials have described them as grieving and isolated -- was visited by Progress 10, an automated Russian space ferry.
The vehicle has close to three tonnes of food, research gear and other supplies, enough to sustain the astronauts at least through June.
Further Progress visits scheduled later this year should adequately supply the crew, officials said, and -- if need be -- the astronauts can be retrieved or relieved on a scheduled April flight by a Russian Soyuz craft.
Despite the problems, officials of the National Aeronautics and Space Administration insist the space station will survive, as it has survived two decades of budget battles and revisions of its mission and design.
Maj. Gen. Michael Kostelnik, the NASA deputy associate administrator for the space station and space shuttle, called the space station "a key and essential staging ground for what comes next" and said the Bush administration was committed to seeing it expand.
He said the proposed budget included money to proceed with long-term expansion plans.
SHUTTLES HELPED TO KEEP THE 200-TONNE STATION FROM SINKING
The budget also calls for refining the Orbital Space Plane, a reusable craft that may eventually replace the Soyuz vehicles now used as the station's lifeboat, he said.
Perhaps the biggest question, if the delays persist, is how to keep the 200-tonne device -- as capacious as a three-bedroom house -- from sinking out of orbit altogether and incinerating as Columbia did.
It has been routine for each shuttle that delivers a fresh crew or the latest truss or module to boost the expanding assemblage about 12 kilometres upward, countering the steady sinking caused as the station's broad surfaces encounter drag exerted by diffuse molecules of air.
The Russian Progress spacecraft can haul fuel to boost the station, as well, but they will not be visiting nearly enough this year to compensate for the absence of space shuttles, five of which were to have docked before 2004.
The station has its own store of propellant to keep properly positioned, but even those supplies could be depleted eventually, space experts said.
This leads to the troubling calculus about keeping the station in space, said John Pike, a space technology expert and director of globalsecurity.org, a Washington research group.
"Everybody's going to be looking closely at the inventory of Progresses and Soyuz boosters to put them up, and running that against the need to reboost the station," Pike said. "Maybe the answer is that there's more than enough, or just enough, or more than enough for this year, but after that there's a real problem."
He said if the Russian craft could not fill the bill, NASA might have to try to cobble together a tanker of some sort. If the station is not continually boosted higher into space, though, trouble will be inevitable, and will intensify the lower the station drifts.
"The lower you go, the less time you've got," he said.
Besides keeping the station flying, NASA and the other space agencies are grappling with the implications of having the shuttle fleet paralysed just as the space station program is scheduled for a major expansion.
The shuttle and station have evolved in tandem, like mutually dependent organisms. Over the last several years, the shuttle's main purpose has been delivering vital components to the expanding complex of living quarters, power plants, laboratories and other systems.
No other spacecraft can handle the accordion-like solar panels that supply power to the space station or the four-storey truss sections that, when linked like Lego blocks, comprise its spine.
The station began as a single Russian-built 21-tonne component in November 1998. But a succession of shuttles and Russian flights steadily added components and supplies until the most recent additions, in December, brought it to its current size, 41 metres long and close to 200 tonnes.
But NASA officials had looked ahead to 2003 as a critical juncture.
This year was to have been the busiest year yet in bringing the station from its original embryonic state -- in which its single module and paired solar wings gave it the look of a housefly -- to its full-flowered metamorphosis as an orbiting laboratory, dormitory and observatory as sprawling and intricate as a mated pair of giant dragonflies.
Pending improvements included the addition of small but important safety systems like additional shields to protect living quarters against penetration by micrometeoroids. But Rob Navias, a NASA spokesman, said "any launch delays would not pose a threat to the safety" of the space station.
By early 2004, electrical power capacity was to have nearly tripled. Forty tonnes of additional pieces were to have been added during two dozen space walks, including four new trusses, extending its skeleton from 41 metres to 94 metres.
It would be ready then for the addition of a major node with attachment points for more labs and other facilities. It would also be ready for more than its current limit of three crew members.
Even before the loss of Columbia, European space officials, particularly, had been pressing the Bush administration not to cut the budget and delay expansion plans, as it had been favouring. Now everything is being re-evaluated once again.
American and European officials working on the project said they're scrambling to figure out the next steps: not only how to sustain the station in orbit, but also how to sustain political and public interest in its lofty, but ill-defined, mission.
One option not being considered is mothballing the station.
"We don't want to leave it unmanned because we're exploring, we're doing science, we have a mission," said Col. Robert Cabana, an astronaut who directs flight crew operations at the Lyndon B. Johnson Space Center in Houston. "The crew is working very hard up there. They've got a lot to do. And it just wouldn't be right to quit."
In Europe and in Houston, station officials said problems were bound to multiply for the mission as more time elapsed.
"We must concentrate on the explanation of what occurred and we must know soon how long the fleet is grounded," said Lionel Suchet, a senior official with the French counterpart to NASA, the National Center for Space Studies.
RESEARCH WILL NEVER TAKE OFF IF SPACE STATION REMAINS SMALL
Keeping momentum toward expanding the station is vital if significant science is to be accomplished, several government space officials said. Already, much of the time available to the station's three-person crews is spent in running, expanding or maintaining its systems or orbit.
Supporters of the station insist that, already, even in its limited configuration, it is producing valuable data on biological, industrial and other questions. The eventual design, with the capacity of two Boeing 747 cabins, is intended to accommodate six crew members. Only then will substantial research be possible, experts said.
Everything now hinges on timing. The longer it takes to solve the Columbia conundrum, the more troubles will loom for the station, and for coming up with options.
"If it's something that is fairly easy to fix, then that's one thing," said John Douglass, president of the Aerospace Industries Association, a trade group representing big space-technology firms.
"But if it's a really significant problem that causes them to reassess the shuttle's risk equation, then we're drifting into a pretty serious situation ... ."
GRAPHIC: Graphic;Diagram: Journal Stock; (See hard copy for Graphic;Diagram).
Copyright © 2003, CanWest Interactive, a division of CanWest Global Communications Corp.
