CAPE CANAVERAL, Fla. -- Spacewalking astronauts will christen the International Space Station's new doorway to orbit early Saturday, opening up a new stage for a $60 billion construction project that involves 16 nations on four continents.
Dressed up in hulking spacesuits, Michael Gernhardt and James Reilly will become the first astronauts to float out of the $164 million airlock, which will enable outpost crews to carry out their own spacewalking assembly or repair work in the absence of a visiting shuttle.
And unlike any spacewalk mounted from a shuttle, there will be no cargo bay floor beneath the astronauts' feet as they head out into open space -- just a blue planet below.
"It'll be like stepping off into the big void, dropping down toward Earth," Gernhardt said.
Added Reilly: "We're really looking forward to it."
The inaugural spacewalk from the Quest airlock is set to begin at 12:09 a.m. EDT (0409 GMT). Working in concert with station robot arm operator Susan Helms, the astronauts aim to install the last of four high-pressure gas tanks on the outer shell of the two-room chamber.
Dubbed "doghouses" because of their size and shape, the 1,200-pound (540-kilogram) tanks -- two of which are filled with oxygen, and two of which contain nitrogen -- will be used to replenish air supplies within the airlock.
The oxygen tanks and a nitrogen tank were attached during a spacewalk Wednesday. And once the final nitrogen tank is in place, the astronauts will carry out some lofty inspection work.Climbing nine stories above the shuttle, Gernhardt and Reilly will examine a motor drive at the base of the station's $600 million electric power tower, which features massive American solar arrays that have a wingspan of 240 feet (73 meters).
The electrically actuated motor drive, which enables the solar arrays to track the sun, has been generating more current than expected and engineers want the astronauts to check it for any obvious damage.
The spacewalkers also will inspect the station's so-called Floating Potential Probe, a device designed to determine whether the huge solar wings present an electrical shock hazard to astronauts working outside the station.
The apparatus only beams back data on a periodic basis, and engineers want the spacewalkers to check status lights to make certain it is in fact operating.
The inspection work, meanwhile, will give the astronauts a spectacular view of the growing station, which is being built by space agencies in the U.S., Russia, Canada, Japan, Europe and Brazil.
Ten stories bigger than it was a year ago, the station initially consisted of a Russian space tug and the U.S. Unity module, building blocks that were launched and linked in space in late 1998.
advertisement
