The International Space Station is, of course, far too large and elaborate to be assembled on Earth and then launched into space en masse; instead, says Steve Francois, ISS Director of Launch Site Support, astronauts will assemble the station in space like a giant, floating erector set, module by module, over a period of years.

The first component will enter near-earth orbit in June, when Russia launches the Functional Cargo Block (or FGB, the Russian acronym), which will generate power and provide for ground communications during the early stages of construction. Through periodic thruster firings, this essential element will also maintain the orbit of the station, which would otherwise be pulled back toward Earth by atmospheric drag.

Functional Cargo Block

Two weeks later, the space shuttle Endeavor will deliver Node 1, the first U.S.-built element, into near-Earth orbit. This module, currently at the Space Station Processing Facility at the Kennedy Space Center in Florida, is being put through the mandatory paces prior to launch. But by July 1998, after a series of daring spacewalks to connect wires, cables, and the like, Node 1 and the FGB will be joined.

Created as a passageway between the modules, Node 1 will eventually connect the U.S. Laboratory and the U.S. Habitation module. Its six hatches will serve as docking ports for other modules; and since Russian and American modules require different hatches, two of those six ports will be connected to Pressurized Mating Adapters (PMAs,) which work to adjust the size of the opening depending upon the need.

Node 1

"In the case of the Node," Francois says, "the structure will be 95 percent complete upon launch. But that still leaves five percent of the components that need to be installed." Indeed, while astronauts put the finishing touches on Node 1 outside the Earth's atmosphere, ground control will be checking the system and turning on functions so the work can begin.

Once Node 1 is in orbit, of course, much work remains. After the Endeavour mission, 43 more launches will follow. According to the schedule, in fact, the station won't be habitable until December 1998, with the launch and installation of Russia's service module. This essential component, the cornerstone for the first human habitation of the station, will provide the early station living quarters, life support system, electrical power distribution, data processing system, flight control system, and propulsion system. Although many of these systems will be supplemented or replaced by later U.S. station components, the Service Module will always remain the structural and functional center for Russia's segment of the ISS.

X-38: Crew Return Vehicle

According to NASA, modules will be sent up through the year 2002 and beyond. In fact, like a child's dream Lego set, the International Space Station may remain a perpetual work in progress as new technologies and concepts in space design are explored. "I'm like the mechanic in the garage," says Francois. "I love putting it together, I want to see it work, I want to get it there. No one's built one like this before. There's never an end to it, and there's always the next step, and the next."

Indeed, cross-cultural engineering ensures that the task will be complex. Some of the design details for these flights have not been resolved, as the partner agencies work to ensure that their plans all match, says NASA engineer Kelle Pido. "The NASA side of the project is much further along than the European side," she notes, "so now the Europeans must make adjustments. Luckily, it's just technical, as we say. There's almost always an answer and a way out."

Russian Research Module

Yet when so many nations work together to put the pieces in place, the puzzle is not just technical. For instance, engineers have had to choose a measurement system. (For the record, the metric system will be used, and English will be the official standard language, although Russian elements of the station will also use Russian in their instrumentation.) And because missions to construct the Station are interdependent, a slip in the schedule by any one of the partner agencies can throw the entire program off schedule. That has already happened this year, as the Russian Space Agency's funding troubles forced a delay in the completion of the Service Module -- heart of the living quarters -- the third station element to be put in place. To account for the delay, the Space Station Control Board -- a group comprised of representatives from the five partner agencies -- revised the assembly sequence in May; they also programmed extra flights to make up for future delays.

"We can sit around our offices and argue things to absolute death," says Pido, "but the you go to these multilateral meetings and you can actually accomplish things. We all have the same basic goals."