Spacewalkers complete tricky wiring job

December 8, 1998
by Paul Hoversten

HOUSTON -- Both halves of the new International Space Station were wired for power Monday as Endeavour spacewalkers Jerry Ross and Jim Newman performed a tricky electrical job.
 

Delicate job: Astronaut Jerry Ross works on the International Space Station Monday.

The two shuttle astronauts were scheduled to spend 6.5 hours scaling the sides of the 76-foot-long station, plugging in 40 electrical and data cables between the Russian-built Zarya module and the U.S.-built Unity.

The connections, designed to rout Zarya's electrical power into Unity, amount to "the nervous system, if not the heart, of the space station," said Bob Castle, lead flight director.

The station juts like a seven-story mast from space shuttle Endeavour's cargo bay. Today, Commander Bob Cabana will fire the shuttle's thruster rockets, raising the altitude by 3.5 miles, to 245.5 miles above Earth.

That's where the shuttle will drop the station off Sunday before Endeavour and its six astronauts return to Earth next Tuesday.

	?What risks do astronauts take on when they make a spacewalk? What other safety issues or work problems could arise as astronauts perform their tasks? ?How might the decreased gravitational pull in space and bulky 300-pound space suits impact how astronauts use their limbs and hands during a spacewalk? ? Predict how the International Space Station will impact future space programs. If you were given a chance, would you take a space flight? Why or why not?

Before going on their spacewalk, Ross and Newman breathed pure oxygen for 40 minutes to purge nitrogen from their system and avoid the "bends" upon return to Endeavour.

While they were doing that, Russian ground teams outside Moscow sent commands to Zarya to verify that power flowing through the end connected to Unity was shut off, avoiding any potential electrical shock to the spacewalkers.

The two started their spacewalk about 20 minutes early, at 5:10 p.m. ET, as Endeavour passed over the southern Atlantic Ocean east of the Falkland Islands.

Ross, 50, rode at the end of the shuttle's 50-foot-long robot arm while Newman, 42, held onto handrails on the sides of the station.

It was tedious work that required a deft touch as the spacewalkers took extra care not to bend any pins in the connectors. A bent pin could thwart a firm mating.

Coordinating the work via radio inside Endeavour was pilot Rick Sturckow, who double-checked that the spacewalkers put the right cables together.

Ross and Newman will make two more spacewalks Wednesday and Saturday to finish outfitting the station pieces. The shuttle's crew will enter the station for the first time Thursday.

Monday's excursion was the first of 162 spacewalks needed to complete the 100-piece, $ 50 billion station by 2004. It will take 35 more space shuttle and eight Russian rocket flights to finish the assembly.