Harmony module pulled from cargo bay
BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: October 26, 2007
Astronauts Stephanie Wilson and Dan Tani, operating the space station's robot arm, carefully pulled the 31,500-pound Harmony module from the shuttle Discovery's cargo bay today for attachment to the international lab complex. Spectacular video beamed down from the shuttle showed the massive module being slowly maneuvered above the spaceplane over toward the left side of the outpost where it will be installed on the central Unity module.
Spacewalkers Scott Parazynski and Doug Wheelock, meanwhile, worked at the top of the central Z1 truss to prepare a huge set of stowed solar arrays for relocation to the far left side of the station's main solar power truss later in the mission. Parazynski's main goal was to disconnect four ammonia coolant lines between the P6 solar array to the Z1 truss and to remate them to dummy connectors on Z1. He also had to cap the open lines on the P6 side of the interface and secure the quick-disconnect fittings.
Before launch, Parazynski said he worried about ammonia leakage and potential contamination. The valves in question have "been open now for almost seven years," he said. "I would envision we will take a little bit of ammonia contamination, hopefully not a lot. We are well trained to handle anything that might happen along those lines. But they are very difficult to handle, I don't have a perfect work site for it, so that'll be one of the things that will be very challenging on the flight."
As it turned out, only a few ammonia ice crystals were reported as the umbilicals were disconnected and remated. But that was enough to trigger a contamination inspection. The concern was the potential for carrying unseen ammonia ice crystals back into the space station.
"If I took any hits it was mostly at the chest level, I believe," Parazynski said. "And Wheels, they looked like just little tiny pieces of ice or almost hail."
But Wheelock did not see any signs of contamination on Parazynski's suit.
"The sun's coming up. But again, I don't see anything, Scott, I don't see any discoloration or anything that looks waxy or a different texture. Can you see that, Paolo? I don't see anything."
"Roger, copy," Italian astronaut Paolo Nespoli replied from inside the shuttle. "And Houston, I guess you followed along. I'm not sure if you have wireless (television) or not. But it looks like EV-2 (Wheelock) is not seeing any contamination on EV-1 (Parazynski)."
The spacewalkers then focused on attaching thermal shrouds to protect a stowed radiator on P6 and two electronics boxes toward the top of the array truss.
Wilson and Tani, meanwhile, carefully positioned Harmony to line it up for attachment to the Unity module using motor-driven bolts in a so-called common berthing mechanism, or CBM. The attachment does not require the spacewalkers and will be carried out robotically.
"And Scott and Wheels, do you have a minute? Nespoli asked as the shuttle-station complex sailed high above the Gulf of Mexico.
"If you look down, starboard side, you're about the pass right over Houston. Say hello to MCC (mission control center)."
"Starboard side, huh?" Parazynski asked.
"That's affirm, you see the coastline there," Nespoli said.
"Ooohhhh, look at that!"
"Oh, that's beautiful."
"Hello, Houston!" Parazynski said.
A few minutes later, Parazynski caught site of Harmony nearing its attachment point on the Unity module.
"Hey Wheels, look down, ISS nadir, you'll see that they've got the node about two meters out," he said.
"Oh, my goodness!"
"Isn't that great?"
"Hey, what do you think? Robeau and all the gang here have been working hard," Nespoli said, referring to Wilson by her mission nickname.
"Yes, they have," Parazynski agreed.
"All right, let's get going here," Nespoli said. "We have one hour and 10 minutes to go."