Space station planners take two small steps

While they cheer the shuttle's return to service, architects of the international space station Freedom welcome progress toward NASA's orbital dream house as well. Their project also passed a milestone last week.

On Wednesday, NASA concluded contract negotiations for a $6.7 billion set of work packages to design, test, and deliver the hardware for the United States' share of Freedom.

Then as Discovery began orbiting Earth Thursday, representatives of Canada, the European Space Agency (ESA), Japan, and the US signed the formal documents that officially establish their space station partnership.

``I guess it really puts the bee on us now to get our part done,'' says Clarke Covington, manager of the Space Station Projects Office at the Johnson Space Center.

Congress and the administration have been equivocal about funding their share of the project. They have ordered several restudies and cost-cutting redesign. The foreign partners, in contrast, have long been ready to put up their contribution. It amounts to about 20 percent of the $20 billion to $25 billion estimated station cost.

``Those folks are off and running, and they're putting a lot of money into it,'' Mr. Covington observes. He adds, somewhat wistfully, ``They've got a commitment to [that funding] from their governments and they're very serious about it.''

NASA, on the other hand, awaits a decision by the next President as to whether or not the US will proceed with the program.

It now seems likely that the decision will be favorable. Both presidential candidates - George Bush and Michael Dukakis - have endorsed Freedom. Furthermore, it would be diplomatically embarrassing for the US to back out of the pact that has just been signed.

Nevertheless, Congress has put the program in a financial squeeze. NASA now can use only $385 million of the $900 million Congress voted for the station program in fiscal 1989. The balance will become available in mid-May only if the new President wants it.

The funding delay is ``a real restriction that causes us to throttle down and level off for over half a year,'' when other partners are ready to move ahead, Covington says.

The need to resolve this fiscal uncertainty is one reason that 1989 is a critical year for the station program. The other reason is that NASA and its partners must begin to make final decisions about the actual hardware design.

As now conceived, Freedom will be built on a truss that is 150 meters (492 feet) long with solar power units on each end. These units deliver 75 kilowatts of electric power. Three laboratory modules and one living module will be mounted midway along the truss. The US is supplying the living module and one laboratory module. ESA and Japan are each supplying one laboratory module. And Canada is providing a movable service center with grappling arms.

Contracts that NASA has just negotiated with McDonnell Douglas Astronautics, Boeing Aerospace Company, Rockwell International, and General Electric cover all but the foreign-supplied components of this station.

As Covington explains, NASA and its partners cannot wait for next year's presidential decision to move ahead with the space station design. They have already started to develop and approve the final detailed specifications. And crucial work on these plans will be done between now and the end of next year.

The specifications include a seldom-mentioned decision as to whether or not to make the US part of Freedom measurable in metric units. It is a seemingly small decision that could have a big impact, and planners will make it within the next couple of months.

Covington explains that there is a wealth of space-qualified parts, all of which are specified in English units of measurement. Interfaces with foreign hardware must accommodate metric measurements. But to make the US units entirely metric would set a major precedent and would force a painful conversion, he says.

Despite US uncertainties, the space station idea seems to be moving ahead under a momentum of its own.

The question, then, is not whether or not there will be a space station, Covington notes. The Soviets have Mir. The Japanese and Europeans talk of eventually having stations of their own, if need be. The question is, rather, ``whether there will be a US space station.''